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Sample records for pictorial essay mammography

  1. Rhombencephalitis: pictorial essay.

    PubMed

    Campos, Líllian Gonçalves; Trindade, Régis Augusto Reis; Faistauer, Ângela; Pérez, Juliano Adams; Vedolin, Leonardo Modesti; Duarte, Juliana Ávila

    2016-01-01

    The term rhombencephalitis refers to inflammatory diseases affecting the hindbrain (brainstem and cerebellum). Rhombencephalitis has a wide variety of etiologies, including infections, autoimmune diseases, and paraneoplastic syndromes. Infection with bacteria of the genus Listeria is the most common cause of rhombencephalitis. Primary rhombencephalitis caused by infection with Listeria spp. occurs in healthy young adults. It usually has a biphasic time course with a flu-like syndrome, followed by brainstem dysfunction; 75% of patients have cerebrospinal fluid pleocytosis, and nearly 100% have an abnormal brain magnetic resonance imaging scan. However, other possible causes of rhombencephalitis must be borne in mind. In addition to the clinical aspects, the patterns seen in magnetic resonance imaging can be helpful in defining the possible cause. Some of the reported causes of rhombencephalitis are potentially severe and life threatening; therefore, an accurate initial diagnostic approach is important to establishing a proper early treatment regimen. This pictorial essay reviews the various causes of rhombencephalitis and the corresponding magnetic resonance imaging findings, by describing illustrative confirmed cases.

  2. Rhombencephalitis: pictorial essay*

    PubMed Central

    Campos, Líllian Gonçalves; Trindade, Régis Augusto Reis; Faistauer, Ângela; Pérez, Juliano Adams; Vedolin, Leonardo Modesti; Duarte, Juliana Ávila

    2016-01-01

    The term rhombencephalitis refers to inflammatory diseases affecting the hindbrain (brainstem and cerebellum). Rhombencephalitis has a wide variety of etiologies, including infections, autoimmune diseases, and paraneoplastic syndromes. Infection with bacteria of the genus Listeria is the most common cause of rhombencephalitis. Primary rhombencephalitis caused by infection with Listeria spp. occurs in healthy young adults. It usually has a biphasic time course with a flu-like syndrome, followed by brainstem dysfunction; 75% of patients have cerebrospinal fluid pleocytosis, and nearly 100% have an abnormal brain magnetic resonance imaging scan. However, other possible causes of rhombencephalitis must be borne in mind. In addition to the clinical aspects, the patterns seen in magnetic resonance imaging can be helpful in defining the possible cause. Some of the reported causes of rhombencephalitis are potentially severe and life threatening; therefore, an accurate initial diagnostic approach is important to establishing a proper early treatment regimen. This pictorial essay reviews the various causes of rhombencephalitis and the corresponding magnetic resonance imaging findings, by describing illustrative confirmed cases. PMID:27818548

  3. Fetal MRI: A pictorial essay

    PubMed Central

    Rathee, Sapna; Joshi, Priscilla; Kelkar, Abhimanyu; Seth, Nagesh

    2016-01-01

    Ultrasonography (USG) is the primary method for antenatal fetal evaluation. However, fetal magnetic resonance imaging (MRI) has now become a valuable adjunct to USG in confirming/excluding suspected abnormalities and in the detection of additional abnormalities, thus changing the outcome of pregnancy and optimizing perinatal management. With the development of ultrafast sequences, fetal MRI has made remarkable progress in recent times. In this pictorial essay, we illustrate a spectrum of structural abnormalities affecting the central nervous system, thorax, genitourinary and gastrointestinal tract, as well as miscellaneous anomalies. Anomalies in twin gestations and placental abnormalities have also been included. PMID:27081224

  4. Unusual lesions that distend the knee joint: pictorial essay*

    PubMed Central

    de Lima, Luana T. Barros; de Albuquerque Filho, Eolo Santana; Batista, Laecio Leitão; de Moraes, Talita Peixoto; Pereira, Bruno Perez Guedes

    2016-01-01

    The high number of knee imaging exams at radiology clinics, together with the wide variety of knee disorders, calls for expanding the knowledge about the less common lesions seen in routine diagnostic practice. The purpose of this pictorial essay was to illustrate unusual lesions that distend the knee joint, selected by relevance and evaluated with multiple imaging modalities, including X-ray, computed tomography, and magnetic resonance imaging, as well as to perform a brief review of the literature. PMID:27818547

  5. MRI of Uncommon Lesions of the Large Bowel: A Pictorial Essay

    PubMed Central

    Lee, Christine U; Glockner, James F

    2014-01-01

    This pictorial essay briefly discusses methods for optimizing bowel imaging with magnetic resonance imaging (MRI) and illustrates the MRI appearance of a variety of unusual lesions involving or related specifically to the large bowel. PMID:25806129

  6. Imaging in spinal posterior epidural space lesions: A pictorial essay.

    PubMed

    Gala, Foram B; Aswani, Yashant

    2016-01-01

    Spinal epidural space is a real anatomic space located outside the dura mater and within the spinal canal extending from foramen magnum to sacrum. Important contents of this space are epidural fat, spinal nerves, epidural veins and arteries. Due to close proximity of posterior epidural space to spinal cord and spinal nerves, the lesions present with symptoms of radiculopathy and/or myelopathy. In this pictorial essay, detailed anatomy of the posterior epidural space, pathologies affecting it along with imaging pearls to accurately diagnose them are discussed. Various pathologies affecting the posterior epidural space either arising from the space itself or occurring secondary to vertebral/intervertebral disc pathologies. Primary spinal bone tumors affecting the posterior epidural space have been excluded. The etiological spectrum affecting the posterior epidural space ranges from degenerative, infective, neoplastic - benign or malignant to miscellaneous pathologies. MRI is the modality of choice in evaluation of these lesions with CT scan mainly helpful in detecting calcification. Due to its excellent soft tissue contrast, Magnetic Resonance Imaging is extremely useful in assessing the pathologies of posterior epidural space, to know their entire extent, characterize them and along with clinical history and laboratory data, arrive at a specific diagnosis and guide the referring clinician. It is important to diagnose these lesions early so as to prevent permanent neurological complication.

  7. Imaging in spinal posterior epidural space lesions: A pictorial essay

    PubMed Central

    Gala, Foram B; Aswani, Yashant

    2016-01-01

    Spinal epidural space is a real anatomic space located outside the dura mater and within the spinal canal extending from foramen magnum to sacrum. Important contents of this space are epidural fat, spinal nerves, epidural veins and arteries. Due to close proximity of posterior epidural space to spinal cord and spinal nerves, the lesions present with symptoms of radiculopathy and/or myelopathy. In this pictorial essay, detailed anatomy of the posterior epidural space, pathologies affecting it along with imaging pearls to accurately diagnose them are discussed. Various pathologies affecting the posterior epidural space either arising from the space itself or occurring secondary to vertebral/intervertebral disc pathologies. Primary spinal bone tumors affecting the posterior epidural space have been excluded. The etiological spectrum affecting the posterior epidural space ranges from degenerative, infective, neoplastic - benign or malignant to miscellaneous pathologies. MRI is the modality of choice in evaluation of these lesions with CT scan mainly helpful in detecting calcification. Due to its excellent soft tissue contrast, Magnetic Resonance Imaging is extremely useful in assessing the pathologies of posterior epidural space, to know their entire extent, characterize them and along with clinical history and laboratory data, arrive at a specific diagnosis and guide the referring clinician. It is important to diagnose these lesions early so as to prevent permanent neurological complication. PMID:27857455

  8. Neuroimaging findings of congenital Zika virus infection: a pictorial essay.

    PubMed

    Zare Mehrjardi, Mohammad; Poretti, Andrea; Huisman, Thierry A G M; Werner, Heron; Keshavarz, Elham; Araujo Júnior, Edward

    2017-03-01

    Zika virus (ZIKV) is a mosquito-borne arbovirus from the Flaviviridae family. It had caused several epidemics since its discovery in 1947, but there was no significant attention to this virus until the recent outbreak in Brazil in 2015. The main concern is the causal relationship between prenatal ZIKV infection and congenital microcephaly, which has been confirmed recently. Moreover, ZIKV may cause other central nervous system abnormalities such as brain parenchymal atrophy with secondary ventriculomegaly, intracranial calcification, malformations of cortical development (such as polymicrogyria, and lissencephaly-pachygyria), agenesis/hypoplasia of the corpus callosum, cerebellar and brainstem hypoplasia, sensorineural hearing-loss, and ocular abnormalities as well as arthrogryposis in the infected fetuses. Postnatal (acquired) ZIKV infection usually has an asymptomatic or mildly symptomatic course, while prenatal (congenital) ZIKV infection has a more severe course and may cause severe brain anomalies that are described as congenital Zika syndrome. In this pictorial essay, we aim to illustrate the prenatal and postnatal neuroimaging findings that may be seen in fetuses and neonates with congenital Zika syndrome, and will discuss possible radiological differential diagnoses. A detailed knowledge of these findings is paramount for an early correct diagnosis, prognosis determination, and counseling of the affected children and families.

  9. Pictorial essay of radiological features of benign intrathoracic masses

    PubMed Central

    Suut, Syahminan; Al-Ani, Zeid; Allen, Carolyn; Rajiah, Prabhakar; Durr-e-Sabih; AL-Harbi, Abdullah; AL-Jahdali, Hamdan; Khan, Ali Nawaz

    2015-01-01

    With increased exposure of patients to routine imaging, incidental benign intrathoracic masses are frequently recognized. Most have classical imaging features, which are pathognomonic for their benignity. The aim of this pictorial review is to educate the reader of radiological features of several types of intrathoracic masses. The masses are categorized based on their location/origin and are grouped into parenchymal, pleural, mediastinal, or bronchial. Thoracic wall masses that invade the thorax such as neurofibromas and lipomas are included as they may mimic intrathoracic masses. All examples are illustrated and include pulmonary hamartoma, pleural fibroma, sarcoidosis, bronchial carcinoid, and bronchoceles together with a variety of mediastinal cysts on plain radiographs, computed tomography (CT) and magnetic resonance imaging (MRI). Sometimes a multimodality approach would be needed to confirm the diagnosis in atypical cases. The study would include the incorporation of radionuclide studies and relevant discussion in a multidisciplinary setting. PMID:26664560

  10. Mammography

    MedlinePlus

    ... first test. TYPES OF MAMMOGRAPHY Traditional mammography uses film, similar to routine x-rays. Digital mammography is ... risk of dying of breast cancer compared to film mammography. Three-dimensional (3D) mammography is a type ...

  11. Ultrasonography of Various Thyroid Diseases in Children and Adolescents: A Pictorial Essay

    PubMed Central

    Lee, Eun Hye; Jeong, Sun Hye; Park, Jisang; Lee, Heon

    2015-01-01

    Thyroid imaging is indicated to evaluate congenital hypothyroidism during newborn screening or in cases of a palpable thyroid mass in children and adolescents. This pictorial essay reviews the ultrasonography (US) of thyroid diseases in children and adolescents, including normal thyroid gland development, imaging features of congenital thyroid disorders (dysgenesis, [aplasia, ectopy, hypoplasia], dyshormonogenesis, transient hypothyroidism, thyroglossal duct cyst), diffuse thyroid disease (Grave's disease, Hashimoto's thyroiditis, and suppurative thyroiditis), and thyroid nodules. The primary imaging modalities for evaluating thyroid diseases are US and radionuclide scintigraphy. Additionally, US can be used to guide aspiration of detected nodules. PMID:25741204

  12. Ultrasonography of various thyroid diseases in children and adolescents: a pictorial essay.

    PubMed

    Hong, Hyun Sook; Lee, Eun Hye; Jeong, Sun Hye; Park, Jisang; Lee, Heon

    2015-01-01

    Thyroid imaging is indicated to evaluate congenital hypothyroidism during newborn screening or in cases of a palpable thyroid mass in children and adolescents. This pictorial essay reviews the ultrasonography (US) of thyroid diseases in children and adolescents, including normal thyroid gland development, imaging features of congenital thyroid disorders (dysgenesis, [aplasia, ectopy, hypoplasia], dyshormonogenesis, transient hypothyroidism, thyroglossal duct cyst), diffuse thyroid disease (Grave's disease, Hashimoto's thyroiditis, and suppurative thyroiditis), and thyroid nodules. The primary imaging modalities for evaluating thyroid diseases are US and radionuclide scintigraphy. Additionally, US can be used to guide aspiration of detected nodules.

  13. Lymphoma of the scrotum in patients with Down's syndrome: US appearance. Mini-pictorial essay.

    PubMed

    Draghi, F; Bonardi, M; Dellabianca, C; Tarantino, C C; Alessi, S

    2011-12-01

    Down's syndrome is relatively common, and patients who are affected have an increased risk of developing acute leukemia, but not solid tumors. Studies performed in larger patient populations have shown that solid tumors, including lymphomas, are significantly less frequent in Down patients than in children and adults who are not Trisomy 21-affected.Testicular lymphomas are rare and extremely aggressive. Ultrasound (US) combined with color Doppler is essential in the diagnosis and evaluation of treatment results in these lesions. As they are very rare, it was decided to publish this mini-pictorial essay.

  14. Hydatid disease involving some rare locations in the body: a pictorial essay.

    PubMed

    Yuksel, Murvet; Demirpolat, Gulen; Sever, Ahmet; Bakaris, Sevgi; Bulbuloglu, Ertan; Elmas, Nevra

    2007-01-01

    Hydatid disease (HD) is an endemic illness in many countries, and it poses an important public health problem that's influenced by peoples' socioeconomic status and migration that spreads this disease. Although rare, it may occur in any organ or tissue. The most common site is the liver (59-75%), followed in frequency by lung (27%), kidney (3%), bone (1-4%) and brain (1-2%). Other sites such as the heart, spleen, pancreas and muscles are very rarely affected. Unusual sites for this disease can cause diagnostic problems. This pictorial essay illustrates various radiological findings of HD in the liver, spleen, kidney, pancreas, peritoneal cavity, omentum, adrenal, ovary, lung, mediastinum and retroperitoneum. Familiarity with the imaging findings of HD may be helpful in making an accurate diagnosis and preventing potential complications.

  15. Artificial ascites and pneumoperitoneum to facilitate thermal ablation of liver tumors: a pictorial essay.

    PubMed

    Bhagavatula, Sharath K; Chick, Jeffrey F B; Chauhan, Nikunj R; Shyn, Paul B

    2017-02-01

    Image-guided percutaneous thermal ablation is increasingly utilized in the treatment of hepatic malignancies. Peripherally located hepatic tumors can be difficult to access or located adjacent to critical structures that can be injured. As a result, ablation of peripheral tumors may be avoided or may be performed too cautiously, leading to inadequate ablation coverage. In these cases, separating the tumor from adjacent critical structures can increase the efficacy and safety of procedures. Artificial ascites and artificial pneumoperitoneum are techniques that utilize fluid and gas, respectively, to insulate critical structures from the thermal ablation zone. Induction of artificial ascites and artificial pneumoperitoneum can enable complete ablation of otherwise inaccessible hepatic tumors, improve tumor visualization, minimize unintended thermal injury to surrounding organs, and reduce post-procedural pain. This pictorial essay illustrates and discusses the proper technique and clinical considerations for successful artificial ascites and pneumoperitoneum creation to facilitate safe peripheral hepatic tumor ablation.

  16. Magnetic Resonance Imaging of Non-ischemic Cardiomyopathies: A Pictorial Essay.

    PubMed

    Olivas-Chacon, Cristina I; Mullins, Carola; Stewart, Kevan; Akle, Nassim; Calleros, Jesus E; Ramos-Duran, Luis R

    2015-01-01

    Non-ischemic cardiomyopathies are defined as either primary or secondary diseases of the myocardium resulting in cardiac dysfunction. While primary cardiomyopathies are confined to the heart and can be genetic or acquired, secondary cardiomyopathies show involvement of the heart as a manifestation of an underlying systemic disease including metabolic, inflammatory, granulomatous, infectious, or autoimmune entities. Non-ischemic cardiomyopathies are currently classified as hypertrophic, dilated, restrictive, or unclassifiable, including left ventricular non-compaction. Cardiovascular Magnetic Resonance Imaging (CMRI) not only has the capability to assess cardiac morphology and function, but also the ability to detect edema, hemorrhage, fibrosis, and intramyocardial deposits, providing a valuable imaging tool in the characterization of non-ischemic cardiomyopathies. This pictorial essay shows some of the most important non-ischemic cardiomyopathies with an emphasis on magnetic resonance imaging features.

  17. Magnetic Resonance Imaging of Non-ischemic Cardiomyopathies: A Pictorial Essay

    PubMed Central

    Olivas-Chacon, Cristina I; Mullins, Carola; Stewart, Kevan; Akle, Nassim; Calleros, Jesus E; Ramos-Duran, Luis R

    2015-01-01

    Non-ischemic cardiomyopathies are defined as either primary or secondary diseases of the myocardium resulting in cardiac dysfunction. While primary cardiomyopathies are confined to the heart and can be genetic or acquired, secondary cardiomyopathies show involvement of the heart as a manifestation of an underlying systemic disease including metabolic, inflammatory, granulomatous, infectious, or autoimmune entities. Non-ischemic cardiomyopathies are currently classified as hypertrophic, dilated, restrictive, or unclassifiable, including left ventricular non-compaction. Cardiovascular Magnetic Resonance Imaging (CMRI) not only has the capability to assess cardiac morphology and function, but also the ability to detect edema, hemorrhage, fibrosis, and intramyocardial deposits, providing a valuable imaging tool in the characterization of non-ischemic cardiomyopathies. This pictorial essay shows some of the most important non-ischemic cardiomyopathies with an emphasis on magnetic resonance imaging features. PMID:26199786

  18. Mammography

    MedlinePlus

    ... mammography facility. top of page What does the equipment look like? A mammography unit is a rectangular ... be notified of the results by the mammography facility. Follow-up examinations may be necessary, and your ...

  19. Helical CT Angiography of Abdominal Aortic Aneurysms Treated with Suprarenal Stent Grafting: A Pictorial Essay

    SciTech Connect

    Sun Zhonghua

    2003-06-15

    The endovascular repair of abdominal aorticaneurysm (AAA) with stent grafts is rapidly becoming an important alternative to open repair. Suprarenal stent grafting, recently modified from conventional infrarenal stent grafting, is a technique for the purpose of treating patients with inappropriate aneurysm necks.Unlike open repair, the success of endoluminal repair cannot be ascertained by means of direct examination and thus relies on imaging results. The use of conventional angiography for arterial imaging has become less dominant, while helical computed tomography angiography(CTA) has become the imaging modality of choice for both preoperative assessment and postoperative followup after treatment with stent graft implants. There is an increasing likelihood that radiologists will become more and more involved in the procedure of aortic stent grafting and in giving the radiological report on these patients treated with stent grafts. It is necessary for radiologists to be familiar with the imaging findings, including common and uncommon appearances following aortic stent grafting. The purpose of this pictorial essay is to describe and present normal and abnormal imaging appearances following aortic stent grafting based on helical CTA.

  20. "Unforgettable" - a pictorial essay on anatomy and pathology of the hippocampus.

    PubMed

    Dekeyzer, Sven; De Kock, Isabelle; Nikoubashman, Omid; Vanden Bossche, Stephanie; Van Eetvelde, Ruth; De Groote, Jeroen; Acou, Marjan; Wiesmann, Martin; Deblaere, Karel; Achten, Eric

    2017-04-01

    The hippocampus is a small but complex anatomical structure that plays an important role in spatial and episodic memory. The hippocampus can be affected by a wide range of congenital variants and degenerative, inflammatory, vascular, tumoral and toxic-metabolic pathologies. Magnetic resonance imaging is the preferred imaging technique for evaluating the hippocampus. The main indications requiring tailored imaging sequences of the hippocampus are medically refractory epilepsy and dementia. The purpose of this pictorial review is threefold: (1) to review the normal anatomy of the hippocampus on MRI; (2) to discuss the optimal imaging strategy for the evaluation of the hippocampus; and (3) to present a pictorial overview of the most common anatomic variants and pathologic conditions affecting the hippocampus.

  1. [Role of modern cross-sectional imaging in thanatology: a pictorial essay].

    PubMed

    Dedouit, F; Otal, P; Costagliola, R; Loubes Lacroix, F; Telmon, N; Rouge, D; Joffre, F

    2006-06-01

    The development of new imaging modalities such as computed tomography and magnetic resonance imaging is a new phenomenon in thanatology. The growing accessibility to these technologies allows, under some conditions, the acquisition of cross-sectional images on cadavers. The authors present a practical pictorial review of post-mortem changes and deadly injuries, illustrating the contributions of modern cross-sectional imaging techniques in thanatology.

  2. Imaging of common breast implants and implant-related complications: A pictorial essay.

    PubMed

    Shah, Amisha T; Jankharia, Bijal B

    2016-01-01

    The number of women undergoing breast implant procedures is increasing exponentially. It is, therefore, imperative for a radiologist to be familiar with the normal and abnormal imaging appearances of common breast implants. Diagnostic imaging studies such as mammography, ultrasonography, and magnetic resonance imaging are used to evaluate implant integrity, detect abnormalities of the implant and its surrounding capsule, and detect breast conditions unrelated to implants. Magnetic resonance imaging of silicone breast implants, with its high sensitivity and specificity for detecting implant rupture, is the most reliable modality to asses implant integrity. Whichever imaging modality is used, the overall aim of imaging breast implants is to provide the pertinent information about implant integrity, detect implant failures, and to detect breast conditions unrelated to the implants, such as cancer.

  3. From Grey Scale B-Mode to Elastosonography: Multimodal Ultrasound Imaging in Meningioma Surgery-Pictorial Essay and Literature Review.

    PubMed

    Prada, Francesco; Del Bene, Massimiliano; Moiraghi, Alessandro; Casali, Cecilia; Legnani, Federico Giuseppe; Saladino, Andrea; Perin, Alessandro; Vetrano, Ignazio Gaspare; Mattei, Luca; Richetta, Carla; Saini, Marco; DiMeco, Francesco

    2015-01-01

    The main goal in meningioma surgery is to achieve complete tumor removal, when possible, while improving or preserving patient neurological functions. Intraoperative imaging guidance is one fundamental tool for such achievement. In this regard, intra-operative ultrasound (ioUS) is a reliable solution to obtain real-time information during surgery and it has been applied in many different aspect of neurosurgery. In the last years, different ioUS modalities have been described: B-mode, Fusion Imaging with pre-operative acquired MRI, Doppler, contrast enhanced ultrasound (CEUS), and elastosonography. In this paper, we present our US based multimodal approach in meningioma surgery. We describe all the most relevant ioUS modalities and their intraoperative application to obtain precise and specific information regarding the lesion for a tailored approach in meningioma surgery. For each modality, we perform a review of the literature accompanied by a pictorial essay based on our routinely use of ioUS for meningioma resection.

  4. From Grey Scale B-Mode to Elastosonography: Multimodal Ultrasound Imaging in Meningioma Surgery—Pictorial Essay and Literature Review

    PubMed Central

    Moiraghi, Alessandro; Casali, Cecilia; Legnani, Federico Giuseppe; Perin, Alessandro; Mattei, Luca; Richetta, Carla; Saini, Marco

    2015-01-01

    The main goal in meningioma surgery is to achieve complete tumor removal, when possible, while improving or preserving patient neurological functions. Intraoperative imaging guidance is one fundamental tool for such achievement. In this regard, intra-operative ultrasound (ioUS) is a reliable solution to obtain real-time information during surgery and it has been applied in many different aspect of neurosurgery. In the last years, different ioUS modalities have been described: B-mode, Fusion Imaging with pre-operative acquired MRI, Doppler, contrast enhanced ultrasound (CEUS), and elastosonography. In this paper, we present our US based multimodal approach in meningioma surgery. We describe all the most relevant ioUS modalities and their intraoperative application to obtain precise and specific information regarding the lesion for a tailored approach in meningioma surgery. For each modality, we perform a review of the literature accompanied by a pictorial essay based on our routinely use of ioUS for meningioma resection. PMID:26101779

  5. Pictorial essay: Salivary gland imaging

    PubMed Central

    Rastogi, Rajul; Bhargava, Sumeet; Mallarajapatna, Govindarajan Janardan; Singh, Sudhir Kumar

    2012-01-01

    Salivary glands are the first organs of digestion secreting their digestive juices into the oral cavity. Parotid, submandibular, and sublingual glands are the major paired salivary glands in the decreasing order of their size. In addition, multiple small minor salivary glands are noted randomly distributed in the upper aerodigestive tract, including paranasal sinuses and parapharyngeal spaces. The imaging is directed to the major salivary glands. Commonly used imaging methods include plain radiography and conventional sialography. Recently, high-resolution ultrasonography (HRUS) is being increasingly used for targeted salivary gland imaging. However, the advent of cross-sectional imaging techniques such as computed tomography (CT) and magnetic resonance imaging (MRI) have revolutionized the imaging of salivary glands. This article illustrates the role of imaging in evaluating the variegated disease pattern of the major salivary glands. PMID:23833425

  6. Aspiration pneumonia in children: an iconographic essay.

    PubMed

    de Oliveira, Gabriel Antonio; Pessanha, Laís Bastos; Guerra, Luiz Felipe Alves; Martins, Diego Lima Nava; Rondina, Ronaldo Garcia; Silva, Jamine Ronacher Passos

    2015-01-01

    In most cases of aspiration pneumonia in children, the disease is specific to this age group. Clinical and radiological correlation is essential for the diagnosis. The present pictorial essay is aimed at showing typical images of the most common etiologies.

  7. Bone tumor mimickers: A pictorial essay

    PubMed Central

    Mhuircheartaigh, Jennifer Ni; Lin, Yu-Ching; Wu, Jim S

    2014-01-01

    Focal lesions in bone are very common and many of these lesions are not bone tumors. These bone tumor mimickers can include numerous normal anatomic variants and non-neoplastic processes. Many of these tumor mimickers can be left alone, while others can be due to a significant disease process. It is important for the radiologist and clinician to be aware of these bone tumor mimickers and understand the characteristic features which allow discrimination between them and true neoplasms in order to avoid unnecessary additional workup. Knowing which lesions to leave alone or which ones require workup can prevent misdiagnosis and reduce patient anxiety. PMID:25114385

  8. Revisiting Ectopic Pregnancy: A Pictorial Essay

    PubMed Central

    Petrides, Artemis; Dinglas, Cheryl; Chavez, Martin; Taylor, Sharon; Mahboob, Sabrina

    2014-01-01

    Ectopic pregnancies occur in approximately 1.4% of all pregnancies and account for 15% of pregnancy-related deaths. Considering the high degree of mortality, recognizing an ectopic pregnancy is important. Signs and symptoms of an ectopic pregnancy are nonspecific and include pain, vaginal bleeding, and an adnexal mass. Therefore, imaging can play a critical role in diagnosis. There are different types of ectopic pregnancies, which are tubal, cornual, cesarean scar, cervical, heterotopic, abdominal, and ovarian. Initial imaging evaluation of pregnant patients with pelvic symptoms is by ultrasonography, transabdominal, transvaginal or both. We review the sonographic appearance of different types of ectopic pregnancies that will aid in accurate and prompt diagnosis. PMID:25161806

  9. US anatomy of the shoulder: Pictorial essay.

    PubMed

    Precerutti, M; Garioni, E; Madonia, L; Draghi, F

    2010-12-01

    A thorough knowledge of the anatomy of the shoulder is essential for the assessment of its condition. The purpose of this article is to provide a useful tool for the ultrasound (US) study of this joint. The shoulder girdle and upper arm are made up of a number of muscles and tendons: rotator cuff (supraspinatus, infraspinatus, teres minor and subscapularis), humeral biceps, deltoid and pectoral muscles, which can all be evaluated at US examination. Various and complex capsular ligamentous structures contribute to the stability of the shoulder, but only a few can be adequately evaluated by US and will therefore receive particular attention. Numerous serous bursae are situated among muscles, skin, subcutaneous tissues, joint capsule structures and bones to prevent friction and they can be evaluated by US only in the presence of pathologies. Subacromial-subdeltoid and subcoracoid bursa are most frequently involved and will therefore be described in detail. There are furthermore nerves and vessels providing the various components of the shoulder with innervation and vascularization, and they can also be studied by US. The shoulder girdle (humerus, scapula, clavicle and sternal manubrium) is situated in the deep layers; only the cortex of the bone can be seen at US as a continuous hyperechoic line. For a better understanding of the location and relationship between the structures which can be studied by US, magnetic resonance imaging (MRI) can be carried out as this method provides a wider and more complete view of the structures.

  10. MDCT evaluation of sternal variations: Pictorial essay

    PubMed Central

    Duraikannu, Chary; Noronha, Olma V; Sundarrajan, Pushparajan

    2016-01-01

    Sternal variations and anomalies have been identified in the past during autopsy or cadaveric studies. Recently, an increasing number of minor sternal variations have been reported with the advent of multidetector computed tomography (CT). Although there are many sternal variations that occur with varying appearance and prevalence, most of them are not recognized or are underreported during routine imaging of thorax. Identification of sternal variations is important to differentiate from pathological conditions and to prevent fatal complications prior to sternal interventions like marrow aspiration or acupuncture. This article aims to describe the minor and asymptomatic sternal variations by multidetector CT and their clinical significance. PMID:27413263

  11. Abdominal manifestations of extranodal lymphoma: pictorial essay*

    PubMed Central

    Fajardo, Laís; Ramin, Guilherme de Araujo; Penachim, Thiago José; Martins, Daniel Lahan; Cardia, Patrícia Prando; Prando, Adilson

    2016-01-01

    In the appropriate clinical setting, certain aspects of extranodal abdominal lymphoma, as revealed by current cross-sectional imaging techniques, should be considered potentially diagnostic and can hasten the diagnosis. In addition, diagnostic imaging in the context of biopsy-proven lymphoma can accurately stage the disease for its appropriate treatment. The purpose of this article was to illustrate the various imaging aspects of extranodal lymphoma in the abdomen. PMID:28057966

  12. Valuing Essays: Essaying Values

    ERIC Educational Resources Information Center

    Badley, Graham

    2010-01-01

    The essay regularly comes under attack. It is criticised for being rigidly linear rather than flexible and reflective. I first challenge this view by examining reasons why the essay should be valued as an important genre. Secondly, I propose that in using the essay form students and academics necessarily exemplify their own critical values. Essays…

  13. Ambiguity in pictorial depth.

    PubMed

    Battu, Balaraju; Kappers, Astrid M L; Koenderink, Jan J

    2007-01-01

    Pictorial space is the 3-D impression that one obtains when looking 'into' a 2-D picture. One is aware of 3-D 'opaque' objects. 'Pictorial reliefs' are the surfaces of such pictorial objects in 'pictorial space'. Photographs (or any pictures) do in no way fully specify physical scenes. Rather, any photograph is compatible with an infinite number of possible scenes that may be called 'metameric scenes'. If pictorial relief is one of these metameric scenes, the response may be considered 'veridical'. The conventional usage is more restrictive and is indeed inconsistent. Thus the observer has much freedom in arriving at such a 'veridical' response. To address this ambiguity, we determined the pictorial reliefs for eight observers, six pictures, and two psychophysical methods. We used 'methods of cross-sections' to operationalise pictorial reliefs. We find that linear regression of the depths of relief at corresponding locations in the picture for different observers often lead to very low (even insignificant) R2s. Thus the responses are idiosyncratic to a large degree. Perhaps surprisingly, we also observed that multiple regression of depth and picture coordinates at corresponding locations often lead to very high R2s. Often R2s increased from insignificant up to almost 1. Apparently, to a large extent 'depth' is irrelevant as a psychophysical variable, in the sense that it does not uniquely account for the relation of the response to the pictorial structure. This clearly runs counter to the bulk of the literature on pictorial 'depth perception'. The invariant core of interindividual perception proves to be of an 'affine' rather than a Euclidean nature; that is to say, 'pictorial space' is not simply the picture plane augmented with a depth dimension.

  14. Pictorial Superiority Effect

    ERIC Educational Resources Information Center

    Nelson, Douglas L.; And Others

    1976-01-01

    Pictures generally show superior recognition relative to their verbal labels. This experiment was designed to link this pictorial superiority effect to sensory or meaning codes associated with the two types of symbols. (Editor)

  15. Aspiration pneumonia in children: an iconographic essay*

    PubMed Central

    de Oliveira, Gabriel Antonio; Pessanha, Laís Bastos; Guerra, Luiz Felipe Alves; Martins, Diego Lima Nava; Rondina, Ronaldo Garcia; Silva, Jamine Ronacher Passos

    2015-01-01

    In most cases of aspiration pneumonia in children, the disease is specific to this age group. Clinical and radiological correlation is essential for the diagnosis. The present pictorial essay is aimed at showing typical images of the most common etiologies. PMID:26811557

  16. FDA Certified Mammography Facilities

    MedlinePlus

    ... Products Radiation-Emitting Products Home Radiation-Emitting Products Mammography Quality Standards Act and Program Consumer Information (MQSA) ... it Email Print This list of FDA Certified Mammography Facilities is updated weekly. If you click on ...

  17. Barriers to screening mammography.

    PubMed

    Sarma, Elizabeth A

    2015-01-01

    Breast cancer (BRCA) is the second most commonly diagnosed cancer among women in the USA, and mammography is an effective means for the early detection of BRCA. Identifying the barriers to screening mammography can inform research, policy and practice aiming to increase mammography adherence. A literature review was conducted to determine common barriers to screening mammography adherence. PsycINFO and PubMed databases were searched to identify studies published between 2000 and 2012 that examined barriers associated with reduced mammography adherence. Three thematic groups of barriers, based on social ecology, were identified from the literature: healthcare system-level, social and individual-level barriers. Researchers must consider screening behaviour in context and, therefore, should simultaneously consider each level of barriers when attempting to understand screening behaviour and create interventions to increase mammography adherence.

  18. Diogene pictorial drift chamber

    SciTech Connect

    Gosset, J.

    1984-01-01

    A pictorial drift chamber, called DIOGENE, has been installed at Saturne in order to study central collisions of high energy heavy ions. It has been adapted from the JADE internal detector, with two major differences to be taken into account. First, the center-of-mass of these collisions is not identical to the laboratory reference frame. Second, the energy loss and the momentum ranges of the particles to be detected are different from the ones in JADE. It was also tried to keep the cost as small as possible, hence the choice of minimum size and minimum number of sensitive wires. Moreover the wire planes are shifted from the beam axis: this trick helps very much to quickly reject the bad tracks caused by the ambiguity of measuring drift distances (positive or negative) through times (always positive).

  19. Fatty lesions in and around the heart: a pictorial review

    PubMed Central

    Restrepo, C S; Ocazionez, D; Suby-Long, T; Vargas, D

    2015-01-01

    A wide variety of fat-containing entities occur in and near the heart. These findings are often encountered by radiologists and may be incidental or the reason for the patient's clinical presentation. Cross-sectional imaging helps to characterize the extent of these lesions and to formulate a differential diagnosis, which varies by lesion location, imaging features and patient demographics. The purpose of this pictorial essay is to familiarize radiologists with these fat-containing lesions and to help avoid misdiagnosis and errors in management. This pictorial review will discuss the normal fatty structures in and around the heart. A range of common and uncommon fat-containing lesions will then be reviewed based upon lesion location. PMID:25950727

  20. FDA Certified Mammography Facilities

    MedlinePlus

    ... Program Consumer Information (MQSA) Search for a Certified Facility Share Tweet Linkedin Pin it More sharing options ... Email Print This list of FDA Certified Mammography Facilities is updated weekly. If you click on Search ...

  1. MR imaging in deep pelvic endometriosis: a pictorial essay.

    PubMed

    Coutinho, Antônio; Bittencourt, Leonardo Kayat; Pires, Cíntia E; Junqueira, Flávia; Lima, Cláudio Márcio Amaral de Oliveira; Coutinho, Elisa; Domingues, Marisa A; Domingues, Romeu C; Marchiori, Edson

    2011-01-01

    Deep pelvic endometriosis is an important gynecologic disorder that is responsible for severe pelvic pain and is defined as subperitoneal invasion that exceeds 5 mm in depth. Deep pelvic endometriosis can affect the retrocervical region, uterosacral ligaments, rectum, rectovaginal septum, vagina, urinary tract, and other extraperitoneal pelvic sites. It is commonly associated with dysmenorrhea, dyspareunia, pelvic pain, urinary tract symptoms, and infertility. Because surgery remains the best therapeutic option for affected patients, the accurate preoperative assessment of the extension of endometriotic disease is extremely important. Pelvic magnetic resonance (MR) imaging is a noninvasive method with high spatial resolution that allows multiplanar evaluation of deep pelvic endometriosis and good tissue characterization, but without the use of ionizing radiation or iodinated contrast agents. MR imaging yields important findings that help grade the disease and identify subperitoneal lesion extension and other associated disease entities, thereby facilitating accurate diagnosis and adequate treatment. Radiologists should be familiar with the MR imaging findings of deep infiltrating endometriosis in various anatomic locations so that they can provide information that allows adequate presurgical counseling.

  2. Conflicts, snapping and instability of the tendons. Pictorial essay

    PubMed Central

    Fantino, Olivier; Borne, J.; Bordet, Bertrand

    2012-01-01

    Conflicts, snapping and instability of the tendons are common, and ultrasound (US) is the method of choice for evidencing these conditions thanks to the possibility to perform dynamic maneuvers during imaging studies. A conflict can occur between a tendon and a bone structure, other tendons, the retinacula or pulleys. Snapping can occur due to instability caused by rupture of the retinaculum, conflict between a thickened retinaculum and a bone prominence or due to an abnormal position of the tendon. Instability can occur due to insufficient ability of the retinaculum to keep the tendons in the bone groove or its failure to hold the tendons applied to the bone. The technique for evidencing conflicts, snapping and instability of the tendons is very demanding because it requires a thorough knowledge of the US appearance and dynamic maneuvers. However, at the present time US examination completed with dynamic maneuvers is the investigation of choice for evidencing these disorders and providing the clinicians with the necessary information. PMID:23396604

  3. FDOPA Patterns in Adrenal Glands: A Pictorial Essay.

    PubMed

    Moreau, Aurélie; Giraudet, Anne Laure; Kryza, David; Borson-Chazot, Françoise; Bournaud-Salinas, Claire; Mognetti, Thomas; Lifante, Jean-Christophe; Combemale, Patrick; Giammarile, Francesco; Houzard, Claire

    2017-05-01

    F-FDOPA is a well-established tool to explore pheochromocytomas. It tends to replace I-MIBG scan in metastatic pheochromocytomas, multiple endocrine neoplasia type 2-related tumors, succinate dehydrogenase [ubiquinone] iron-sulfur subunit-negative tumors, and succinate dehydrogenase[ZERO WIDTH SPACE]-positive lesions. To our knowledge, no study has characterized physiological and pathological adrenal glands with F-FDOPA from a quantitative point of view. We report the features of different normal and pathological adrenal glands with F-FDOPA. Within our series, only pheochromocytomas present a significantly increased uptake reflecting the high specificity of this tracer. Tumors such as adenomas or myelolipomas present no F-FDOPA significant accumulation. Interestingly, adrenal gland hyperplasia and solitary glands do not demonstrate compensatory uptake.

  4. Conflicts, snapping and instability of the tendons. Pictorial essay.

    PubMed

    Fantino, Olivier; Borne, J; Bordet, Bertrand

    2012-02-01

    Conflicts, snapping and instability of the tendons are common, and ultrasound (US) is the method of choice for evidencing these conditions thanks to the possibility to perform dynamic maneuvers during imaging studies. A conflict can occur between a tendon and a bone structure, other tendons, the retinacula or pulleys. Snapping can occur due to instability caused by rupture of the retinaculum, conflict between a thickened retinaculum and a bone prominence or due to an abnormal position of the tendon. Instability can occur due to insufficient ability of the retinaculum to keep the tendons in the bone groove or its failure to hold the tendons applied to the bone.The technique for evidencing conflicts, snapping and instability of the tendons is very demanding because it requires a thorough knowledge of the US appearance and dynamic maneuvers. However, at the present time US examination completed with dynamic maneuvers is the investigation of choice for evidencing these disorders and providing the clinicians with the necessary information.

  5. Uncommon Causes of Acute Abdominal Pain – A Pictorial Essay

    PubMed Central

    Hariharan, Mahesh; Balasubramaniam, Rajan; Shetty, Sharath Kumar; Yadavalli, Shanthala; Ahetasham, Mohammed; Devarapalli, Sravya

    2016-01-01

    Acute abdomen is one of the most common clinical conditions requiring a radiological investigation. Ultrasound is the primary modality of choice which can diagnose some of the common causes of acute abdomen. However, sometimes the underlying cause for the pain is far more complicated than expected mandating a high degree of suspicion to suggest further investigation with contrast enhanced computed tomography or magnetic resonance imaging. Here, we have compiled a comprehensive series of selected cases to highlight the conditions which can be easily overlooked unless carefully sought for. This article also emphasizes the importance of multimodality approach to arrive at the final diagnosis with an increased overall diagnostic accuracy which in turn improves patient management and prognosis. PMID:27014500

  6. Anatomy of the triceps surae: a pictorial essay.

    PubMed

    Dalmau-Pastor, Miquel; Fargues-Polo, Betlem; Casanova-Martínez, Daniel; Vega, Jordi; Golanó, Pau

    2014-12-01

    Gastrocnemius contracture has recently gained relevance owing to its suggested relationship with foot disorders such as metatarsalgia, plantar fasciopathy, hallux valgus, and others. Consequently this has induced a renewed interest in surgical lengthening techniques, including proximal gastrocnemius release, to resolve gastrocnemius contracture in patients with foot disorders. This article describes and discusses the general anatomy of the triceps surae and the surgical anatomy of the gastrocnemius.

  7. Pictorial essay: Complications of a swallowed fish bone.

    PubMed

    Bathla, Girish; Teo, Lynette Ls; Dhanda, Sunita

    2011-01-01

    Unintentional ingestion of a fishbone (FB) is common, especially in populations with a high consumption of seafood. In most instances, the ingested FB passes uneventfully through the gastrointestinal (GI) tract, usually within a week. However, in certain cases, the FB may become impacted and lead to complications. Awareness of these complications is important as patients usually present with nonspecific symptoms and could be unaware of having ingested an FB.

  8. Scholarly Essays.

    ERIC Educational Resources Information Center

    American Education, 1983

    1983-01-01

    A selection of essays by 12 1983 Presidential Scholars entitled Opportunity in America; Under the Influence of High Fashion; Law and Human Freedom; The Effects of Computers in Education; Prejudice, Cultural Heritage, and National Unity; The Visual Artist in a Technological Society; Dorothy Meets Schopenhauer; Rise Above; and Mathematics as a…

  9. The design of pictorial instruments

    NASA Technical Reports Server (NTRS)

    Ellis, Stephen R.

    1995-01-01

    An historical overview of the development and design of pictorial displays is presented with particular emphasis on the research related to civilian aerospace applications carried out at the Ames Research Center. The use of geometric and symbolic enhancements to counteract the inherent ambiguities in perspective projections is discussed with reference to an aircraft traffic display application. Current design and perceptual issues related to head-mounted systems for virtual environment simulation and telepresence displays are also discussed. Finally, the importance of incorporating error display and control in the design of pictorial displays is addressed in the context of an orbital maneuver planning application.

  10. Mammography and Other Screening Tests for Breast Problems

    MedlinePlus

    ... What are the risks of mammography? • What is digital mammography? • What is a clinical breast exam? • How ... mammogram does not increase cancer risk. What is digital mammography? Digital mammography is a type of mammography ...

  11. Toxic and metabolic encephalopathies: iconographic essay*

    PubMed Central

    Bimbato, Eric Mendonça; Carvalho, Amanda Gontijo; Reis, Fabiano

    2015-01-01

    Generally, toxic-metabolic diseases affecting the central nervous system can hardly be differentiated just on the basis of their clinical presentation. However, some typical neuroradiological features can guide the correct diagnosis. In this context, magnetic resonance imaging is an important tool which, in association with clinical and laboratory data, can establish an early and specific treatment. The present pictorial essay with selected cases from the archives of the authors' institution describes imaging findings which might help in the etiologic diagnosis of toxic-metabolic diseases. PMID:25987753

  12. Toxic and metabolic encephalopathies: iconographic essay.

    PubMed

    Bimbato, Eric Mendonça; Carvalho, Amanda Gontijo; Reis, Fabiano

    2015-01-01

    Generally, toxic-metabolic diseases affecting the central nervous system can hardly be differentiated just on the basis of their clinical presentation. However, some typical neuroradiological features can guide the correct diagnosis. In this context, magnetic resonance imaging is an important tool which, in association with clinical and laboratory data, can establish an early and specific treatment. The present pictorial essay with selected cases from the archives of the authors' institution describes imaging findings which might help in the etiologic diagnosis of toxic-metabolic diseases.

  13. Pictorial communication: Pictures and the synthetic universe

    NASA Technical Reports Server (NTRS)

    Ellis, Stephen R.

    1989-01-01

    Principles for the design of dynamic spatial instruments for communicating quantitative information to viewers are considered through a brief review of the history of pictorial communication. Pictorial communication is seen to have two directions: (1) from the picture to the viewer; and (2) from the viewer to the picture. Optimization of the design of interactive instruments using pictorial formats requires an understanding of the manipulative, perceptual, and cognitive limitations of human viewers.

  14. Positron emission mammography imaging

    SciTech Connect

    Moses, William W.

    2003-10-02

    This paper examines current trends in Positron Emission Mammography (PEM) instrumentation and the performance tradeoffs inherent in them. The most common geometry is a pair of parallel planes of detector modules. They subtend a larger solid angle around the breast than conventional PET cameras, and so have both higher efficiency and lower cost. Extensions to this geometry include encircling the breast, measuring the depth of interaction (DOI), and dual-modality imaging (PEM and x-ray mammography, as well as PEM and x-ray guided biopsy). The ultimate utility of PEM may not be decided by instrument performance, but by biological and medical factors, such as the patient to patient variation in radiotracer uptake or the as yet undetermined role of PEM in breast cancer diagnosis and treatment.

  15. Mammography accreditation program

    SciTech Connect

    Wilcox, P.

    1993-12-31

    In the mid-1980`s, the movement toward the use of dedicated mammography equipment provided significant improvement in breast cancer detection. However, several studies demonstrated that this change was not sufficient to ensure optimal image quality at a low radiation dose. In particular, the 1985 Nationwide Evaluation of X-ray Trends identified the wide variations in image quality and radiation dose, even from dedicated units. During this time period, the American Cancer Society (ACS) launched its Breast Cancer Awareness Screening Campaign. However, there were concerns about the ability of radiology to respond to the increased demand for optimal screening examinations that would result from the ACS program. To respond to these concerns, the ACS and the American College of Radiology (ACR) established a joint committee on mammography screening in 1986. After much discussion, it was decided to use the ACR Diagnostic Practice Accreditation Program as a model for the development of a mammography accreditation program. However, some constraints were required in order to make the program meet the needs of the ACS. This voluntary, peer review program had to be timely and cost effective. It was determined that the best way to address these needs would be to conduct the program by mail. Finally, by placing emphasis on the educational nature of the program, it would provide an even greater opportunity for improving mammographic quality. The result of this effort was that, almost six years ago, in May 1987, the pilot study for the ACR Mammography Accreditation Program (MAP) began, and in August of that year, the first applications were received. In November 1987, the first 3-year accreditation certificates were awarded.

  16. An Intelligent Pictorial Information System

    NASA Astrophysics Data System (ADS)

    Lee, Edward T.; Chang, B.

    1987-05-01

    In examining the history of computer application, we discover that early computer systems were developed primarily for applications related to scientific computation, as in weather prediction, aerospace applications, and nuclear physics applications. At this stage, the computer system served as a big calculator to perform, in the main, manipulation of numbers. Then it was found that computer systems could also be used for business applications, information storage and retrieval, word processing, and report generation. The history of computer application is summarized in Table I. The complexity of pictures makes picture processing much more difficult than number and alphanumerical processing. Therefore, new techniques, new algorithms, and above all, new pictorial knowledge, [1] are needed to overcome the limitatins of existing computer systems. New frontiers in designing computer systems are the ways to handle the representation,[2,3] classification, manipulation, processing, storage, and retrieval of pictures. Especially, the ways to deal with similarity measures and the meaning of the word "approximate" and the phrase "approximate reasoning" are an important and an indispensable part of an intelligent pictorial information system. [4,5] The main objective of this paper is to investigate the mathematical foundation for the effective organization and efficient retrieval of pictures in similarity-directed pictorial databases, [6] based on similarity retrieval techniques [7] and fuzzy languages [8]. The main advantage of this approach is that similar pictures are stored logically close to each other by using quantitative similarity measures. Thus, for answering queries, the amount of picture data needed to be searched can be reduced and the retrieval time can be improved. In addition, in a pictorial database, very often it is desired to find pictures (or feature vectors, histograms, etc.) that are most similar to or most dissimilar [9] to a test picture (or feature

  17. Generalized Instruction following with Pictorial Prompts

    ERIC Educational Resources Information Center

    Phillips, Cara L.; Vollmer, Timothy R.

    2012-01-01

    The benefits of permanent pictorial prompts in enhancing maintenance and generalization are likely dependent on their degree of stimulus control and the extent to which their use is generalized. Although several studies on the use of pictorial prompts have demonstrated their efficacy (e.g., Pierce & Schreibman, 1994; Wacker & Berg, 1983; Wacker,…

  18. [Full-field digital mammography].

    PubMed

    Bick, U

    2000-12-01

    Due to the extremely high image quality requirements in mammography, there has for a long time been no adequate digital alternative to conventional film-screen mammography. The longest experience so far exists with digital mammography on the basis of storage phosphor (CR) systems. However, at normal dose this technique has a relatively poor signal-to-noise ratio and has not found general acceptance. Recently three novel systems for digital mammography by the companies Fischer (slot-scan detector), Trex (CCD-array), and GE (amorphous silicon detector) have been introduced and are currently under clinical investigation. The main advantage of digital mammography is the linear relationship between dose and detector signal with the possibility of a tailored optimization of image contrast. Other advantages include digital image storage, telemammography, and computer-assisted diagnosis.

  19. Facilitating pictorial comprehension with color highlighting.

    PubMed

    McDougald, Brannan R; Wogalter, Michael S

    2014-09-01

    Pictorials can aid in communicating warning information, but viewers may not always correctly comprehend them. Two experiments focused on whether the use of relevant highlighting could benefit pictorial comprehension. A set of warning-related pictorials were manipulated according to three-color highlighting conditions: highlighting areas more relevant to correct comprehension, highlighting areas less relevant to comprehension, and no highlighting. Participants were asked to describe the purpose and meaning of each pictorial presented to them. The findings from both experiments indicate that comprehension of warning pictorials is higher for the relevant highlighting condition than the other two conditions. The highlighting of less relevant areas reduced comprehension compared to no highlighting. Use of appropriately placed highlighting could benefit the design of a complex symbol by pointing out pertinent areas to aid in determining its intended conceptual meaning.

  20. A Photographic Essay of Apache Children in Early Times, Volume 2-Part C.

    ERIC Educational Resources Information Center

    Thompson, Doris; Jacobs, Ben

    As part of a series of guides designed for instruction of American Indian children and youth, this resource guide constitutes a pictorial essay on life of the Apache child from 1880 to the early 20th century. Each of the 12 photographs is accompanied by an historical narrative which describes one or more cultural aspects of Apache childhood.…

  1. A Photographic Essay of Apache Chiefs and Warriors, Volume 2-Part B.

    ERIC Educational Resources Information Center

    Barkan, Gerald; Jacobs, Ben

    As part of a series designed for instruction of American Indian children and youth, this resource guide constitutes a pictorial essay describing forts, Indian agents, and Apache chiefs, warriors, and scouts of the 19th century. Accompanying each picture is a brief historical-biographical narrative. Focus is on Apache resistance to the reservation.…

  2. A Photographic Essay of the San Carlos Apache Indians, Volume 2-Part A.

    ERIC Educational Resources Information Center

    Soto, Ed; And Others

    As part of a series of guides designed for instruction of American Indian children and youth, this resource guide constitutes a pictorial essay on the San Carlos Apache Reservation founded in the late 1800's and located in Arizona's Gila County. An historical narrative and discussion questions accompany each of the 12 photographs. Photographic…

  3. A Photographic Essay of Apache Clothing, War Charms, and Weapons, Volume 2-Part D.

    ERIC Educational Resources Information Center

    Thompson, Doris; Jacobs, Ben

    As part of a series of guides designed for instruction of American Indian children and youth, this resource guide constitutes a pictorial essay on Apache clothing, war charms, and weaponry. A brief historical introduction is followed by 21 question suggestions for classroom use. Each of the 12 photographic topics is accompanied by a descriptive…

  4. Differential Cognitive Cues in Pictorial Depth Perception

    ERIC Educational Resources Information Center

    Omari, Issa M.; Cook, Harold

    1972-01-01

    Predominantly black third-grade children were questioned regarding the relationship of elements in Hudson's Pictorial Depth Perception Task. Performance was significantly affected by the wording of the question. (DM)

  5. Beta Pictoris planet finally imaged?

    NASA Astrophysics Data System (ADS)

    2008-11-01

    A team of French astronomers using ESO's Very Large Telescope have discovered an object located very close to the star Beta Pictoris, and which apparently lies inside its disc. With a projected distance from the star of only 8 times the Earth-Sun distance, this object is most likely the giant planet suspected from the peculiar shape of the disc and the previously observed infall of comets onto the star. It would then be the first image of a planet that is as close to its host star as Saturn is to the Sun. Sharpening Up Jupiter ESO PR Photo 42a/08 Beta Pictoris as seen in infrared light The hot star Beta Pictoris is one of the best-known examples of stars surrounded by a dusty 'debris' disc. Debris discs are composed of dust resulting from collisions among larger bodies like planetary embryos or asteroids. They are a bigger version of the zodiacal dust in our Solar System. Its disc was the first to be imaged -- as early as 1984 -- and remains the best-studied system. Earlier observations showed a warp of the disc, a secondary inclined disc and infalling comets onto the star. "These are indirect, but tell-tale signs that strongly suggest the presence of a massive planet lying between 5 and 10 times the mean Earth-Sun distance from its host star," says team leader Anne-Marie Lagrange. "However, probing the very inner region of the disc, so close to the glowing star, is a most challenging task." In 2003, the French team used the NAOS-CONICA instrument (or NACO [1]), mounted on one of the 8.2 m Unit Telescopes of ESO's Very Large Telescope (VLT), to benefit from both the high image quality provided by the Adaptive Optics system at infrared wavelengths and the good dynamics offered by the detector, in order to study the immediate surroundings of Beta Pictoris. Recently, a member of the team re-analysed the data in a different way to seek the trace of a companion to the star. Infrared wavelengths are indeed very well suited for such searches. "For this, the real challenge

  6. Second Language Incidental Vocabulary Learning: The Effect of Online Textual, Pictorial, and Textual Pictorial Glosses

    ERIC Educational Resources Information Center

    Shahrokni, Seyyed Abdollah

    2009-01-01

    This empirical study investigates the effect of online textual, pictorial, and textual pictorial glosses on the incidental vocabulary learning of 90 adult elementary Iranian EFL learners. The participants were selected from a pool of 140 volunteers based on their performance on an English placement test as well as a knowledge test of the target…

  7. The Formula Essay Reconsidered

    ERIC Educational Resources Information Center

    Haluska, Jan

    2012-01-01

    Bruce Pirie offers the following criticism about formula essays: "What does a five-paragraph essay teach about writing? It teaches that there are rules, and that those rules take the shape of a preordained form, like a cookie-cutter, into which we can pour ideas and expect them to come out well shaped." He goes on to discredit such essays as being…

  8. Local shape of pictorial relief

    PubMed Central

    Koenderink, Jan; van Doorn, Andrea; Wagemans, Johan

    2014-01-01

    How is pictorial relief represented in visual awareness? Certainly not as a “depth map,” but perhaps as a map of local surface attitudes (Koenderink & van Doorn, 1995). Here we consider the possibility that observers might instead, or concurrently, represent local surface shape, a geometrical invariant with respect to motions. Observers judge local surface shape, in a picture of a piece of sculpture, on a five-point categorical scale. Categories are cap–ridge–saddle–rut–cup–flat, where “flat” denotes the absence of shape. We find that observers readily perform such a task, with full resolution of a shape index scale (cap–ridge–saddle–rut–cup), and with excellent self-consistency over days. There exist remarkable inter-observer differences. Over a group of 10 naive observers we find that the dispersion of judgments peaks at the saddle category. There may be a relation of this finding to the history of the topic—Alberti's (1827) omission of the saddle category in his purportedly exhaustive catalog of local surface shapes. PMID:25469225

  9. Rank order scaling of pictorial depth

    PubMed Central

    van Doorn, Andrea; Koenderink, Jan; Wagemans, Johan

    2011-01-01

    We address the topic of “pictorial depth” in cases of pictures that are unlike photographic renderings. The most basic measure of “depth” is no doubt that of depth order. We establish depth order through the pairwise depth-comparison method, involving all pairs from a set of 49 fiducial points. The pictorial space for this study was evoked by a capriccio (imaginary landscape) by Francesco Guardi (1712–1793). In such a drawing pictorial space is suggested by the artist through a small set of conventional depth cues. As a result typical Western observers tend to agree largely in their visual awareness when looking at such art. We rank depths for locations that are not on a single surface and far apart in pictorial space. We find that observers resolve about 40 distinct depth layers and agree largely in this. From a previous experiment we have metrical data for the same observers. The rank correlations between the results are high. Perhaps surprisingly, we find no correlation between the number of distinct depth layers and the total metrical depth range. Thus, the relation between subjective magnitude and discrimination threshold fails to hold for pictorial depth. PMID:23145256

  10. Pictorial depth probed through relative sizes

    PubMed Central

    Wagemans, Johan; van Doorn, Andrea J; Koenderink, Jan J

    2011-01-01

    In the physical environment familiar size is an effective depth cue because the distance from the eye to an object equals the ratio of its physical size to its angular extent in the visual field. Such simple geometrical relations do not apply to pictorial space, since the eye itself is not in pictorial space, and consequently the notion “distance from the eye” is meaningless. Nevertheless, relative size in the picture plane is often used by visual artists to suggest depth differences. The depth domain has no natural origin, nor a natural unit; thus only ratios of depth differences could have an invariant significance. We investigate whether the pictorial relative size cue yields coherent depth structures in pictorial spaces. Specifically, we measure the depth differences for all pairs of points in a 20-point configuration in pictorial space, and we account for these observations through 19 independent parameters (the depths of the points modulo an arbitrary offset), with no meaningful residuals. We discuss a simple formal framework that allows one to handle individual differences. We also compare the depth scale obtained by way of this method with depth scales obtained in totally different ways, finding generally good agreement. PMID:23145258

  11. Quality Imaging — Comparison of CR Mammography with Screen-Film Mammography

    NASA Astrophysics Data System (ADS)

    Gaona, E.; Azorín Nieto, J.; Irán Díaz Góngora, J. A.; Arreola, M.; Casian Castellanos, G.; Perdigón Castañeda, G. M.; Franco Enríquez, J. G.

    2006-09-01

    The aim of this work is a quality imaging comparison of CR mammography images printed to film by a laser printer with screen-film mammography. A Giotto and Elscintec dedicated mammography units with fully automatic exposure and a nominal large focal spot size of 0.3 mm were used for the image acquisition of phantoms in screen-film mammography. Four CR mammography units from two different manufacturers and three dedicated x-ray mammography units with fully automatic exposure and a nominal large focal spot size of 0.3 mm were used for the image acquisition of phantoms in CR mammography. The tests quality image included an assessment of system resolution, scoring phantom images, Artifacts, mean optical density and density difference (contrast). In this study, screen-film mammography with a quality control program offers a significantly greater level of quality image relative to CR mammography images printed on film.

  12. 37 CFR 202.10 - Pictorial, graphic, and sculptural works.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2013-07-01 2013-07-01 false Pictorial, graphic, and... Pictorial, graphic, and sculptural works. (a) In order to be acceptable as a pictorial, graphic, or..., graphic, or sculptural authorship. (b) A claim to copyright cannot be registered in a print or...

  13. 37 CFR 202.10 - Pictorial, graphic, and sculptural works.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2012-07-01 2012-07-01 false Pictorial, graphic, and... Pictorial, graphic, and sculptural works. (a) In order to be acceptable as a pictorial, graphic, or..., graphic, or sculptural authorship. (b) A claim to copyright cannot be registered in a print or...

  14. 37 CFR 202.10 - Pictorial, graphic, and sculptural works.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2014-07-01 2014-07-01 false Pictorial, graphic, and... Pictorial, graphic, and sculptural works. (a) In order to be acceptable as a pictorial, graphic, or..., graphic, or sculptural authorship. (b) A claim to copyright cannot be registered in a print or...

  15. 37 CFR 202.10 - Pictorial, graphic, and sculptural works.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2010-07-01 2010-07-01 false Pictorial, graphic, and... Pictorial, graphic, and sculptural works. (a) In order to be acceptable as a pictorial, graphic, or..., graphic, or sculptural authorship. (b) A claim to copyright cannot be registered in a print or...

  16. 37 CFR 202.10 - Pictorial, graphic, and sculptural works.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2011-07-01 2011-07-01 false Pictorial, graphic, and... Pictorial, graphic, and sculptural works. (a) In order to be acceptable as a pictorial, graphic, or..., graphic, or sculptural authorship. (b) A claim to copyright cannot be registered in a print or...

  17. Pictorial and conceptual representation of glimpsed pictures.

    PubMed

    Potter, Mary C; Staub, Adrian; O'Connor, Daniel H; Potter, Mary C

    2004-06-01

    Pictures seen in a rapid sequence are remembered briefly, but most are forgotten within a few seconds (M. C. Potter. A. Staub, J. Rado. & D. H. O'Connor. 2002). The authors investigated the pictorial and conceptual components of this fleeting memory by presenting 5 pictured scenes and immediately testing recognition of verbal titles (e.g., people at a table) or recognition of the pictures themselves. Recognition declined during testing, but initial performance was higher and the decline steeper when pictures were tested. A final experiment included test decoy pictures that were conceptually similar to but visually distinct from the original pictures. Yeses to decoys were higher than yeses to other distractors. Fleeting memory for glimpsed pictures has a strong conceptual component (conceptual short-term memory), but there is additional highly volatile pictorial memory (pictorial short-term memory) that is not tapped hy a gist title or decoy picture.

  18. Does Pictorial Elucidation Foster Recollection of Idioms?

    ERIC Educational Resources Information Center

    Boers, Frank; Piquer Piriz, Ana Maria; Stengers, Helene; Eyckmans, June

    2009-01-01

    Experimental evidence suggests that pictorial elucidation helps learners comprehend and remember the meaning of second language (L2) idioms. In this article we address the question whether it also helps retention of the form of idioms, i.e. their precise lexical composition. In a small-scale experiment, the meaning of English idioms was clarified…

  19. Pictorial and Conceptual Representation of Glimpsed Pictures

    ERIC Educational Resources Information Center

    Potter, Mary C.; Staub, Adrian; O'Connor, Daniel H.

    2004-01-01

    Pictures seen in a rapid sequence are remembered briefly, but most are forgotten within a few seconds (M. C. Potter. A. Staub, J. Rado. & D. H. O'Connor. 2002). The authors investigated the pictorial and conceptual components of this fleeting memory by presenting 5 pictured scenes and immediately testing recognition of verbal titles (e.g., people…

  20. Differential Cognitive Cues in Pictorial Depth Perception.

    ERIC Educational Resources Information Center

    Omari, Issa M.; Cook, Harold

    The experiment described in this report investigates the effects of various cognitive cues in questions asked regarding the relationship of elements in pictorial depth perception. The subjects of this study are 40 third grade Black and Puerto Rican children. They are confronted with four pictures from the Hudson Depth Perception Tests and asked to…

  1. Ultrasonography of the Kidney: A Pictorial Review

    PubMed Central

    Hansen, Kristoffer Lindskov; Nielsen, Michael Bachmann; Ewertsen, Caroline

    2015-01-01

    Ultrasonography of the kidneys is essential in the diagnosis and management of kidney-related diseases. The kidneys are easily examined, and most pathological changes in the kidneys are distinguishable with ultrasound. In this pictorial review, the most common findings in renal ultrasound are highlighted. PMID:26838799

  2. Breast Cancer and Mammography: Summary of the Educational Impact of a Low-Cost Mammography Program.

    ERIC Educational Resources Information Center

    Gresham, Louise S.; And Others

    1988-01-01

    A mammography public education program which used newspaper press releases, local talk shows, news segments, and announcements, flyers, advertisements, and presentations to companies and select populations increased public awareness and decreased misconceptions about mammography. (CB)

  3. Automated Essay Scoring

    ERIC Educational Resources Information Center

    Dikli, Semire

    2006-01-01

    The impacts of computers on writing have been widely studied for three decades. Even basic computers functions, i.e. word processing, have been of great assistance to writers in modifying their essays. The research on Automated Essay Scoring (AES) has revealed that computers have the capacity to function as a more effective cognitive tool (Attali,…

  4. Improving Achievement Via Essay Exams.

    ERIC Educational Resources Information Center

    Milton, Ohmer

    1979-01-01

    The benefits of using essay tests rather than objective tests in professional education programs are discussed. Essay tests offer practice in writing, creativity and formal communications. Guidelines for using and scoring a sample essay test in biology are presented. (BH)

  5. Frequency-Domain Optical Mammography

    DTIC Science & Technology

    2001-10-01

    optical measurements on breast-like phantoms (Months 19-24) a. Prepare the breast-like phantoms (optical inhomogeneities + strongly scattering...reveals contralateral hemodynamic changes upon hemi- imaging of solid phantoms for optical mammography. Appl Opt field paradigm. Vision Res 41: 97...1064 nm for the Nd:YAG, 660-1180 nm (tunable) for the Ti:sapphire, and 625-780 nm (tunable) for dye lasers using DCM or oxanine 1 dyes. A unique

  6. Digital Mammography with Storage Phosphors

    DTIC Science & Technology

    1993-12-31

    of the data). Phanto imag Image quality of a mammographic unit is often checked with phantoms simulating a breast with the three major disease ...1981; 138:219-22. 28. Andersson I, Andren L, HildelU J, Linell F, Ljungqvist U, Pettersson H: Breast cancer screening with mammography. Radiology...breast scanner (CT/M) in diagnosis of breast diseases . Radiology 1979; 132:647-52. 47. Gisvold JJ,Karsell PR, Reese DF: Computerized tomographic

  7. Rayleigh imaging in spectral mammography

    NASA Astrophysics Data System (ADS)

    Berggren, Karl; Danielsson, Mats; Fredenberg, Erik

    2016-03-01

    Spectral imaging is the acquisition of multiple images of an object at different energy spectra. In mammography, dual-energy imaging (spectral imaging with two energy levels) has been investigated for several applications, in particular material decomposition, which allows for quantitative analysis of breast composition and quantitative contrast-enhanced imaging. Material decomposition with dual-energy imaging is based on the assumption that there are two dominant photon interaction effects that determine linear attenuation: the photoelectric effect and Compton scattering. This assumption limits the number of basis materials, i.e. the number of materials that are possible to differentiate between, to two. However, Rayleigh scattering may account for more than 10% of the linear attenuation in the mammography energy range. In this work, we show that a modified version of a scanning multi-slit spectral photon-counting mammography system is able to acquire three images at different spectra and can be used for triple-energy imaging. We further show that triple-energy imaging in combination with the efficient scatter rejection of the system enables measurement of Rayleigh scattering, which adds an additional energy dependency to the linear attenuation and enables material decomposition with three basis materials. Three available basis materials have the potential to improve virtually all applications of spectral imaging.

  8. Organizational Climates: An Essay

    ERIC Educational Resources Information Center

    Schneider, Benjamin

    1975-01-01

    The purposes of this essay are to (a) present some evidence about the importance of the climate concept as an aid in understanding employee behavior in work organizations and (b) provide a framework for guiding future climate research. (Author)

  9. 2015 Special Operations Essays

    DTIC Science & Technology

    2015-05-01

    Intelligence Agency Relationship since Desert Storm and its Prospects for the Future , May 2014, David P. Oakley Countering the al-Shabaab Insurgency...01 MAY 2015 2. REPORT TYPE N/A 3. DATES COVERED 4. TITLE AND SUBTITLE 2015 Special Operations Essays 5a. CONTRACT NUMBER 5b. GRANT NUMBER...The JSOU Press MacDill Air Force Base, Florida 2015 2015 Special Operations Essays This monograph and other JSOU publications can be found at https

  10. Barriers to Mammography among Inadequately Screened Women

    ERIC Educational Resources Information Center

    Stoll, Carolyn R. T.; Roberts, Summer; Cheng, Meng-Ru; Crayton, Eloise V.; Jackson, Sherrill; Politi, Mary C.

    2015-01-01

    Mammography use has increased over the past 20 years, yet more than 30% of women remain inadequately screened. Structural barriers can deter individuals from screening, however, cognitive, emotional, and communication barriers may also prevent mammography use. This study sought to identify the impact of number and type of barriers on mammography…

  11. Frequently Asked Questions about Digital Mammography

    MedlinePlus

    ... is a mammography system where the x-ray film used in screen-film mammography is replaced by solid-state detectors, similar ... on a computer screen, or printed on special films to look like screen-film mammograms. Types of ...

  12. The Effectiveness of Teaching Science with Pictorial Analogies.

    ERIC Educational Resources Information Center

    Lin, Huann-shyang; And Others

    1996-01-01

    This study uses a conceptual problem-solving test to investigate the effect of a series of pictorial analogies on the concepts of density, pressure, and atmospheric pressure in Year Eight classrooms. Findings indicate that students taught with the pictorial analogies scored significantly higher than their counterparts. Low achievers were the most…

  13. Elementary School Students' Perceptions of Technology in their Pictorial Representations

    ERIC Educational Resources Information Center

    Eristi, Suzan Duygu; Kurt, Adile Askim

    2011-01-01

    The current study aimed to reveal elementary school students' perceptions of technology through their pictorial representations and their written expressions based on their pictorial representations. Content analysis based on the qualitative research method along with art-based inquiry was applied. The "coding system for the concepts revealed…

  14. Social Interactions Sparked by Pictorial Warnings on Cigarette Packs

    PubMed Central

    Hall, Marissa G.; Peebles, Kathryn; Bach, Laura E.; Noar, Seth M.; Ribisl, Kurt M.; Brewer, Noel T.

    2015-01-01

    The Message Impact Framework suggests that social interactions may offer smokers the opportunity to process pictorial warnings on cigarette packs more deeply. We aimed to describe adult smokers’ social interactions about pictorial cigarette pack warnings in two longitudinal pilot studies. In Pilot Study 1, 30 smokers used cigarette packs with one of nine pictorial warnings for two weeks. In Pilot Study 2, 46 smokers used cigarette packs with one of five pictorial warnings for four weeks. Nearly all smokers (97%/96% in Pilot Study 1/2) talked about the warnings with other people, with the most common people being friends (67%/87%) and spouses/significant others (34%/42%). Pilot Study 2 found that 26% of smokers talked about the warnings with strangers. Discussions about the health effects of smoking and quitting smoking were more frequent during the first week of exposure to pictorial warnings than in the week prior to beginning the study (both p < 0.05). Pictorial warnings sparked social interactions about the warnings, the health effects of smoking, and quitting smoking, indicating that pictorial warnings may act as a social intervention reaching beyond the individual. Future research should examine social interactions as a potential mediator of the impact of pictorial warnings on smoking behavior. PMID:26506363

  15. Social Interactions Sparked by Pictorial Warnings on Cigarette Packs.

    PubMed

    Hall, Marissa G; Peebles, Kathryn; Bach, Laura E; Noar, Seth M; Ribisl, Kurt M; Brewer, Noel T

    2015-10-21

    The Message Impact Framework suggests that social interactions may offer smokers the opportunity to process pictorial warnings on cigarette packs more deeply. We aimed to describe adult smokers' social interactions about pictorial cigarette pack warnings in two longitudinal pilot studies. In Pilot Study 1, 30 smokers used cigarette packs with one of nine pictorial warnings for two weeks. In Pilot Study 2, 46 smokers used cigarette packs with one of five pictorial warnings for four weeks. Nearly all smokers (97%/96% in Pilot Study 1/2) talked about the warnings with other people, with the most common people being friends (67%/87%) and spouses/significant others (34%/42%). Pilot Study 2 found that 26% of smokers talked about the warnings with strangers. Discussions about the health effects of smoking and quitting smoking were more frequent during the first week of exposure to pictorial warnings than in the week prior to beginning the study (both p < 0.05). Pictorial warnings sparked social interactions about the warnings, the health effects of smoking, and quitting smoking, indicating that pictorial warnings may act as a social intervention reaching beyond the individual. Future research should examine social interactions as a potential mediator of the impact of pictorial warnings on smoking behavior.

  16. "Mid-Week Pictorial": Pioneer American Photojournalism Magazine.

    ERIC Educational Resources Information Center

    Kenney, Keith

    In 1914 (22 years before the inception of "Life" magazine), the "New York Times" began publishing "Mid-Week Pictorial" to absorb a flood of war pictures pouring in from Europe. Several sociological and technological forces shaped "Mid-Week Pictorial" as a pioneer of American photojournalism magazines,…

  17. Dual-energy contrast-enhanced mammography.

    PubMed

    Travieso Aja, M M; Rodríguez Rodríguez, M; Alayón Hernández, S; Vega Benítez, V; Luzardo, O P

    2014-01-01

    The degree of vascularization in breast lesions is related to their malignancy. For this reason, functional diagnostic imaging techniques have become important in recent years. Dual-energy contrast-enhanced mammography is a new, apparently promising technique in breast cancer that provides information about the degree of vascularization of the lesion in addition to the morphological information provided by conventional mammography. This article describes the state of the art for dual-energy contrast-enhanced mammography. Based on 15 months' clinical experience, we illustrate this review with clinical cases that allow us to discuss the advantages and limitations of this technique.

  18. Digital Mammography and Digital Breast Tomosynthesis.

    PubMed

    Moseley, Tanya W

    2016-06-01

    Breast imaging technology has advanced significantly from the 1930s until the present. American women have a 1 in 8 chance of developing breast cancer. Mammography has been proven in multiple clinical trials to reduce breast cancer mortality. Although a mainstay of breast imaging and improved from film-screen mammography, digital mammography is not a perfect examination. Overlapping obscuring breast tissue limits mammographic interpretation. Breast digital tomosynthesis reduces and/or eliminates overlapping obscuring breast tissue. Although there are some disadvantages with digital breast tomosynthesis, this relatively lost-cost technology may be used effectively in the screening and diagnostic settings.

  19. Family/friend recommendations and mammography intentions: the roles of perceived mammography norms and support

    PubMed Central

    Molina, Yamile; Ornelas, India J.; Doty, Sarah L.; Bishop, Sonia; Beresford, Shirley A. A.; Coronado, Gloria D.

    2015-01-01

    Identifying factors that increase mammography use among Latinas is an important public health priority. Latinas are more likely to report mammography intentions and use, if a family member or friend recommends that they get a mammogram. Little is known about the mechanisms underlying the relationship between social interactions and mammography intentions. Theory suggests that family/friend recommendations increase perceived mammography norms (others believe a woman should obtain a mammogram) and support (others will help her obtain a mammogram), which in turn increase mammography intentions and use. We tested these hypotheses with data from the ¡Fortaleza Latina! study, a randomized controlled trial including 539 Latinas in Washington State. Women whose family/friend recommended they get a mammogram within the last year were more likely to report mammography intentions, norms and support. Perceived mammography norms mediated the relationship between family/friend recommendations and intentions, Mediated Effect = 0.38, 95%CI [0.20, 0.61], but not support, Mediated Effect = 0.002, 95%CI [−0.07, 0.07]. Our findings suggest perceived mammography norms are a potential mechanism underlying the effect of family/friend recommendations on mammography use among Latinas. Our findings make an important contribution to theory about the associations of social interactions, perceptions and health behaviors. PMID:26324395

  20. Family/friend recommendations and mammography intentions: the roles of perceived mammography norms and support.

    PubMed

    Molina, Yamile; Ornelas, India J; Doty, Sarah L; Bishop, Sonia; Beresford, Shirley A A; Coronado, Gloria D

    2015-10-01

    Identifying factors that increase mammography use among Latinas is an important public health priority. Latinas are more likely to report mammography intentions and use, if a family member or friend recommends that they get a mammogram. Little is known about the mechanisms underlying the relationship between social interactions and mammography intentions. Theory suggests that family/friend recommendations increase perceived mammography norms (others believe a woman should obtain a mammogram) and support (others will help her obtain a mammogram), which in turn increase mammography intentions and use. We tested these hypotheses with data from the ¡Fortaleza Latina! study, a randomized controlled trial including 539 Latinas in Washington State. Women whose family/friend recommended they get a mammogram within the last year were more likely to report mammography intentions, norms and support. Perceived mammography norms mediated the relationship between family/friend recommendations and intentions, Mediated Effect = 0.38, 95%CI [0.20, 0.61], but not support, Mediated Effect = 0.002, 95%CI [-0.07, 0.07]. Our findings suggest perceived mammography norms are a potential mechanism underlying the effect of family/friend recommendations on mammography use among Latinas. Our findings make an important contribution to theory about the associations of social interactions, perceptions and health behaviors.

  1. The Centennial Essay.

    ERIC Educational Resources Information Center

    Keeshan, Bob

    1991-01-01

    In this essay, the star of "Captain Kangaroo" points out that more than 20 percent of America's children live below the poverty line. School boards, administrators, and teachers need to make a commitment to address the needs of the whole child. Schools have an opportunity to play a critical role in saving our children. (MLF)

  2. Rethinking the Argumentative Essay

    ERIC Educational Resources Information Center

    Schneer, David

    2014-01-01

    This article investigates the construction of the argumentative essay as it is commonly presented in academic writing textbooks and classrooms for English language learners. The author first examines the traditional three-stage structure (thesis-argument-conclusion) and then problematizes it within a genre-based approach to academic writing. He…

  3. Essays on Character & Opportunity

    ERIC Educational Resources Information Center

    Center on Children and Families at Brookings, 2014

    2014-01-01

    These essays provide richer set of writings on the philosophical, empirical and practical issues raised by a focus on character, and in particular its relationship to questions of opportunity. Each one is an intellectual pemmican: sharp and to the point. Two scholars draw attention to the gendered nature of character formation (Segal and Lexmond);…

  4. Photographic Essay: Sage Staff.

    ERIC Educational Resources Information Center

    Sage: A Scholarly Journal on Black Women, 1986

    1986-01-01

    This essay discusses the severe limitations in employment opportunities for black women during the early 1900s. The collection of photographs depicts black women in the following occupations: (1) nursemaid; (2) fieldhand; (3) dairymaid; (4) laundress; (5) factory worker; (6) beautician; (7) business owner; (8) organization president; and (9)…

  5. Mammography screening services: market segments and messages.

    PubMed

    Scammon, D L; Smith, J A; Beard, T

    1991-01-01

    Mammography has become a vital tool for the early detection of breast cancer. Although many organizations and health care facilities are working to educate and motivate women to take advantage of the life saving opportunity that is offered through screening mammography, only twenty percent of women who should be screened actually have the procedure performed. In order to reach women who have not been screened, it is important to learn which factors most strongly motivate those women who do choose to have a mammogram. Depth interviews with 18 women attending a mobile mammography unit were conducted to explore the decision making process of women obtaining mammography screening services and to develop a profile of prevalent emotions, attitudes, and feelings associated with receiving breast cancer screening services. Analysis of the interview transcripts revealed several important themes to which health care professionals can direct marketing and health promotion strategies.

  6. Pictorial Essay: Exploring Strategies to Develop More Inclusive Approaches to Actor-Training

    ERIC Educational Resources Information Center

    Aita, Sean

    2012-01-01

    In 1975 a new definition of disability, challenging the conventional medical model, was proposed by the Union of the Physically Impaired Against Segregation (UPIAS) and the Disability Alliance. Subsequently extended to cover all impairments, this definition considers disability to be the "disadvantage or restriction caused by a contemporary…

  7. An Atypical Presentation of Multiple Central Osteomas Mimicking Craniofacial Fibrous Dysplasia – A Pictorial Essay

    PubMed Central

    Mhapuskar, Amit A; Hebbale, Manjula; Tepan, Meenal; Ayushee

    2016-01-01

    Osteoma is benign neoplasm with slow growth characterized by deposition of compact lamellar cortical or cancellous bone creating a tumour mass. It is still unclear whether osteomas are benign neoplasms or hamartomas. They have typical clinical presentations and are easily diagnosed with the help of radiographs. We present a rare case of non-syndromic multiple osteomas in the craniofacial region which are typically restricted to the midline and presents radiographically as craniofacial fibrous dysplasia causing a diagnostic dilemma. PMID:28050513

  8. CT of acute perianal abscesses and infected fistulae: a pictorial essay.

    PubMed

    Khati, Nadia J; Sondel Lewis, Nicole; Frazier, Aletta Ann; Obias, Vincent; Zeman, Robert K; Hill, Michael C

    2015-06-01

    Computed tomography (CT) is an effective, readily available diagnostic imaging tool for evaluation of the emergency room (ER) patients with the clinical suspicion of perianal abscess and/or infected fistulous tract (anorectal sepsis). These patients usually present with perineal pain, fever, and leukocytosis. The diagnosis can be easy if the fistulous tract or abscess is visible on inspection of the perianal skin. If the tract or abscess is deep, then the clinical diagnosis can be difficult. Also, the presence of complex tracts or supralevator extension of the infection cannot be judged by external examination alone. Magnetic resonance imaging (MRI) is the best imaging test to accurately detect fistulous tracts, especially when they are complex (Omally et al. in AJR 199:W43-W53, 2012). However, in the acute setting in the ER, this imaging modality is not always immediately available. Endorectal ultrasound has also been used to identify perianal abscesses, but this modality requires hands-on expertise and can have difficulty localizing the offending fistulous tract. It may also require the use of a rectal probe, which the patient may not be able to tolerate. Contrast-enhanced CT is a very useful tool to diagnose anorectal sepsis; however, this has not received much attention in the recent literature (Yousem et al. in Radiology 167(2):331-334, 1988) aside from a paper describing CT imaging following fistulography (Liang et al. in Clin Imaging 37(6):1069-1076, 2013). An infected fistula is indicated by a fluid-/air-filled soft tissue tract surrounded by inflammation. A well-defined round to oval-shaped fluid/air collection is indicative of an abscess. The purpose of this article is to demonstrate the usefulness of contrast-enhanced CT in the diagnosis of acute anorectal sepsis in the ER setting. We will discuss the CT appearance of infected fistulous tracts and abscesses and how CT imaging can guide the ER physician in the clinical management of these patients.

  9. US appearance of partial-thickness supraspinatus tendon tears: Application of the string theory. Pictorial essay

    PubMed Central

    Guerini, H.; Fermand, M.; Godefroy, D.; Feydy, A.; Chevrot, A.; Morvan, G.; Gault, N.; Drapé, J.L.

    2012-01-01

    The supraspinatus tendon is composed of 5 different layers consisting of intertwining bundles. On a front portion of the tendon, the layers become coated bundles which insert on the trochanter. At the insertion, the superficial or bursal surface of the tendon corresponding to the tendon fibers in contact with the subacromial bursa can be distinguished from the deep surface corresponding to the fibers in contact with the glenohumeral joint. A tendon tear may involve partial or total disruption of the tendon fibers and is called full-thickness tear if it affects the entire tendon, and partial-thickness tear if it involves only part of the tendon. Partial-thickness tears of the supraspinatus tendon include lesions of the superficial, deep and central surface or tendon delamination. A contrast enhanced examination requires injection of contrast agent into the joint (arthrography followed by computed tomography (CT) or magnetic resonance imaging (MRI)) to study the deep surface, and injection into the subacromial bursa (bursography followed by CT) to study the superficial surface. MRI and ultrasound (US) examination allow the study of these different tendon layers without the use of contrast agent (which is not possible at CT). PMID:23396264

  10. Amplatzer vascular plug as an embolic agent in different vascular pathologies: A pictorial essay

    PubMed Central

    Tresley, Jonathan; Bhatia, Shivank; Kably, Issam; Poozhikunnath Mohan, Prasoon; Salsamendi, Jason; Narayanan, Govindarajan

    2016-01-01

    The Amplatzer Vascular Plug (AVP) is a cylindrical plug made of self-expanding nitinol wire mesh with precise delivery control, which can be used for a variety of vascular pathologies. An AVP is an ideal vascular occlusion device particularly in high-flow vessels, where there is high risk of migration and systemic embolization with traditional occlusion devices. We performed 28 embolizations using the AVP from 2009 to 2014 and achieved complete occlusion without complications. PMID:27413276

  11. Incidentally detected breast lesions on chest CT with US correlation: a pictorial essay

    PubMed Central

    Son, Jung Hee; Jung, Hyun Kyung; Song, Jong Woon; Baek, Hye Jin; Doo, Kyung Won; Kim, Woogyeong; Kim, Yeon Mee; Kim, Woon Won; Lee, Jung Sun; Cho, Een Young

    2016-01-01

    With the increasing use of computed tomography (CT), incidental breast lesions are detected more frequently. When interpreting chest CT findings, it is important for radiologists to carefully review the breast to recognize any abnormal findings that could affect patient management. The purpose of this study is to discuss incidental breast lesions on chest CT with ultrasonography correlation that may be encountered in routine clinical practice. PMID:27707680

  12. High-resolution computed tomography and histopathological findings in hypersensitivity pneumonitis: a pictorial essay.

    PubMed

    Torres, Pedro Paulo Teixeira E Silva; Moreira, Marise Amaral Rebouças; Silva, Daniela Graner Schuwartz Tannus; da Gama, Roberta Rodrigues Monteiro; Sugita, Denis Masashi; Moreira, Maria Auxiliadora do Carmo

    2016-01-01

    Hypersensitivity pneumonitis is a diffuse interstitial and granulomatous lung disease caused by the inhalation of any one of a number of antigens. The objective of this study was to illustrate the spectrum of abnormalities in high-resolution computed tomography and histopathological findings related to hypersensitivity pneumonitis. We retrospectively evaluated patients who had been diagnosed with hypersensitivity pneumonitis (on the basis of clinical-radiological or clinical-radiological-pathological correlations) and had undergone lung biopsy. Hypersensitivity pneumonitis is clinically divided into acute, subacute, and chronic forms; high-resolution computed tomography findings correlate with the time of exposure; and the two occasionally overlap. In the subacute form, centrilobular micronodules, ground-glass opacities, and air trapping are characteristic high-resolution computed tomography findings, whereas histopathology shows lymphocytic inflammatory infiltrates, bronchiolitis, variable degrees of organizing pneumonia, and giant cells. In the chronic form, high-resolution computed tomography shows traction bronchiectasis, honeycombing, and lung fibrosis, the last also being seen in the biopsy sample. A definitive diagnosis of hypersensitivity pneumonitis can be made only through a multidisciplinary approach, by correlating clinical findings, exposure history, high-resolution computed tomography findings, and lung biopsy findings.

  13. US appearance of partial-thickness supraspinatus tendon tears: Application of the string theory. Pictorial essay.

    PubMed

    Guerini, H; Fermand, M; Godefroy, D; Feydy, A; Chevrot, A; Morvan, G; Gault, N; Drapé, J L

    2012-02-01

    The supraspinatus tendon is composed of 5 different layers consisting of intertwining bundles. On a front portion of the tendon, the layers become coated bundles which insert on the trochanter. At the insertion, the superficial or bursal surface of the tendon corresponding to the tendon fibers in contact with the subacromial bursa can be distinguished from the deep surface corresponding to the fibers in contact with the glenohumeral joint. A tendon tear may involve partial or total disruption of the tendon fibers and is called full-thickness tear if it affects the entire tendon, and partial-thickness tear if it involves only part of the tendon. Partial-thickness tears of the supraspinatus tendon include lesions of the superficial, deep and central surface or tendon delamination.A contrast enhanced examination requires injection of contrast agent into the joint (arthrography followed by computed tomography (CT) or magnetic resonance imaging (MRI)) to study the deep surface, and injection into the subacromial bursa (bursography followed by CT) to study the superficial surface. MRI and ultrasound (US) examination allow the study of these different tendon layers without the use of contrast agent (which is not possible at CT).

  14. Ultrasound images of groin pain in the athlete: a pictorial essay.

    PubMed

    Ozçakar, Levent; Utku, Burkay

    2014-08-01

    Chronic groin pain in the athlete is a common condition, with, at times, protracted recovery that leads to prolonged disability. There are soft-tissue and bony contributors to pain, with the mechanism of injury usually an acute or chronic overload of the hip adductor tendons, abdominal aponeurosis, hip joint, or symphysis pubis. The complexity of the regional anatomy often necessitates imaging modalities for precise diagnosis and prompt management. Imaging options include magnetic resonance imaging, computed tomography, nuclear bone scan, radiography, and ultrasound. In this report, we present a series of images that represent the value of musculoskeletal ultrasound in the diagnosis and treatment of groin pain in the athlete.

  15. Imaging features of primary tumors of the spine: A pictorial essay

    PubMed Central

    Patnaik, Sujata; Jyotsnarani, Y; Uppin, Shantiveer G; Susarla, Rammurti

    2016-01-01

    Primary tumors of spine are rare accounting for less than 5% of new bone tumors diagnosed every year. These tumors may exhibit characteristic imaging features that can help in early diagnosis and improved prognosis. Plasmacytoma/multiple myeloma and lymphoproliferative tumors are the most common malignant primary spinal tumors. Hemangioma is the most common benign tumor of the spine. Computed tomography is useful to assess tumor matrix and osseous change. Magnetic resonance is useful to study associated soft tissue extension, marrow infiltration, and intraspinal extension. Confusing one tumor with the other based on only imaging findings is not uncommon. However, radiologic manifestations of these tumors need to be correlated with the age, sex, location, and presentation to arrive at a close clinical diagnosis. PMID:27413280

  16. Benefits and harms of mammography screening.

    PubMed

    Løberg, Magnus; Lousdal, Mette Lise; Bretthauer, Michael; Kalager, Mette

    2015-05-01

    Mammography screening for breast cancer is widely available in many countries. Initially praised as a universal achievement to improve women's health and to reduce the burden of breast cancer, the benefits and harms of mammography screening have been debated heatedly in the past years. This review discusses the benefits and harms of mammography screening in light of findings from randomized trials and from more recent observational studies performed in the era of modern diagnostics and treatment. The main benefit of mammography screening is reduction of breast-cancer related death. Relative reductions vary from about 15 to 25% in randomized trials to more recent estimates of 13 to 17% in meta-analyses of observational studies. Using UK population data of 2007, for 1,000 women invited to biennial mammography screening for 20 years from age 50, 2 to 3 women are prevented from dying of breast cancer. All-cause mortality is unchanged. Overdiagnosis of breast cancer is the main harm of mammography screening. Based on recent estimates from the United States, the relative amount of overdiagnosis (including ductal carcinoma in situ and invasive cancer) is 31%. This results in 15 women overdiagnosed for every 1,000 women invited to biennial mammography screening for 20 years from age 50. Women should be unpassionately informed about the benefits and harms of mammography screening using absolute effect sizes in a comprehensible fashion. In an era of limited health care resources, screening services need to be scrutinized and compared with each other with regard to effectiveness, cost-effectiveness and harms.

  17. Falling Evaporating Bodies around Beta Pictoris

    NASA Astrophysics Data System (ADS)

    Beust, H.

    2014-09-01

    The edge-on orientation of the beta Pictoris disk as viewed from the Earth enabled the detection of its gaseous counterpart by absorption spectroscopy. This was done as early as 1985 (Vidal-Madjar et al.). Surprisingly, the detected circumstellar absorptions in Ca II, Mg II, etc... lines appeared to often present, next to a central stable component, highly time- variable additional features, Doppler shifted by a few tens, sometimes up to a few hundreds km/s. A huge sample of such features, sometimes presenting very different shapes, has been recorded since that time, especially in the last 10 years thanks to the survey by the HARPS spectrograph. Modeling work in the late 1980's led to propose that these transient spectral events could be due to star-grazing, evaporating planetesimals arising from the disk, that cross the line of sight close to periastron. The absorption components would be due to the gaseous coma around the object, and the Doppler shift to the projection of its velocity onto the line of sight. This model has been thus termed the ÓFalling Evaporating BodiesÓ (FEB) model. Detailed modeling and simulations (Beust et al. 1990, 1996; Karmann et al. 2001, 2003; Fernandez et al. 2006) helped to constrain the physics of the phenomenon and to specify the characteristics of the suspected FEBs, which number may be as large as several hundreds per year. The large number of available data enabled a statistical approach of these events and of their characteristics. It rapidly turned out that the infall of FEBs towards beta Pictoris from the disk was not isotropic. This raised the issue of the dynamical origin of this phenomenon. In the late 1990's, Beust & Morbidelli (1996, 2000) proposed that FEBs could originate from 4:1 and 3:1 mean-motion resonances with a hypothetical giant planet, and fall towards the star thanks to a drastic increase of their eccentricities thanks to the resonances. Exhaustive dynamical simulations led to propose that the suspected

  18. Mammography, thermography, and ultrasound in breast cancer detection

    SciTech Connect

    Basset, L.W.; Gold, R.H.

    1982-01-01

    The book begins with a brief discussion of the history of mammography and a good review and discussion of the mammorgraphy controversy. The section on diagnosis is excellent with very good anatomic-pathologic correlation of the mammography signs. The preoperative localization is well described. Section 3 on performing the examination is an excellent discussion of the various modes of mammography and their techniques. Magnification mammography, computed tomographic mammography, thermography, sonomammography, and ductography are very well covered. In Section 4, the benefits and risk of mammography are well discussed enabling the reader to understand the controversy surrounding breast cancer detection techniques.

  19. Mammography

    MedlinePlus

    ... is similar to having a conventional film mammogram. Computer-aided detection (CAD) systems search digitized mammographic images for abnormal areas of ... standards used by radiology professionals. Modern x-ray systems have very controlled x-ray beams and dose control methods to ...

  20. Family/Friend Recommendations and Mammography Intentions: The Roles of Perceived Mammography Norms and Support

    ERIC Educational Resources Information Center

    Molina, Yamile; Ornelas, India J.; Doty, Sarah L.; Bishop, Sonia; Beresford, Shirley A. A.; Coronado, Gloria D.

    2015-01-01

    Identifying factors that increase mammography use among Latinas is an important public health priority. Latinas are more likely to report mammography intentions and use, if a family member or friend recommends that they get a mammogram. Little is known about the mechanisms underlying the relationship between social interactions and mammography…

  1. Essays on Strategy 6

    DTIC Science & Technology

    1989-01-01

    spoken language . A skilled negotiator must be mindful of the " linguistic fog," which can be quite misleading.75 In a 155 ,,,, ... ... | ii...Policy: A Chinese Perspective 167 Zhu Cheng-hu 8. Is War Obsolete? A Chinese Perspective 189 Fan Zhen Jiang The Editor 203 4 ViiI FOREWORD Strategic...assistance organizations overseas. In addition, Essays on Strategy VI includes two il- luminating articles by Chinese writers--one on the PRC’s view of

  2. Tracking debris disks within the Beta Pictoris Moving Group

    NASA Astrophysics Data System (ADS)

    Debes, J.

    2014-09-01

    Beta Pictoris represents a stunning example of a young planetary system with a debris disk, moving through local space with a host of other co-eval companion stars. These fellow travelers provide additional understanding for placing the Beta Pictoris disk into a proper context with regards to planet formation throughout the galaxy and our own Solar System. I will review the members of the Beta Pictoris moving group and catalog the latest results regarding the presence and understanding of debris disks around these other systems. Since these stars are close and very young, they represent an excellent opportunity for understanding the structure, composition, and grain properties of debris disks.

  3. Essays in microeconomics

    NASA Astrophysics Data System (ADS)

    Davies, Tim

    This dissertation consists of three essays in applied microeconomics. Each essay explores a different issue of economic interest. The essay in Chapter 2 describes an experiment designed to investigate if using assets with an intrinsic value that increases over time leads to persistent undervaluation in laboratory asset trading markets. This question has not previously been investigated by researchers. Results from ten sessions are reported. Three used assets with an intrinsic value that decreased over time. The results from these sessions are consistent with the findings by prior researchers who frequently observed price bubbles in laboratory asset trading experiments. The remaining seven sessions used assets with an intrinsic value that increased over time. In all these sessions trading generally occurred at prices below the asset's intrinsic value. In Chapter 3, in an essay co-authored with Adrian Stoian, we study road running races. Tournaments, where ordinal position determines rewards, are an important component of our economy. By studying sporting tournaments, we hope to shed light on the nature of other economically significant tournaments where data may be less readily available. We separately quantify the sorting and incentive effects of tournament prizes by employing a novel two-part model which we apply to a unique data set of road running race results. We present a counterfactual example of how a hypothetical change in prizes would be predicted to change race participation and speed. In Chapter 4, in an essay co-authored with Jedidiah Brewer and Joseph Cullen, we examine the combined effects of the locations and the brands of retail gasoline outlets in Tucson, Arizona on market prices. We apply an innovative approach to model the impact of competing gas stations that avoids limiting analysis to predetermined nearby locations. We show that increased brand diversity is associated with higher prices and that gas stations affiliated with mass

  4. Part and Whole in Pictorial Relief

    PubMed Central

    Koenderink, Jan; van Doorn, Andrea

    2015-01-01

    What are “natural parts” of pictorial reliefs? Intuitively, and suggested by common lore from the visual arts, they are the bulges that stick out toward the observer. Each such bulge contains a (locally) nearest point and is bounded by one or (usually) more curvilinear ruts. The latter meet in “passes” or saddle points. This divides the relief into “natural districts”. From a formal analysis one knows that reliefs can be divided into “hill districts” or “dale districts”, these two “natural” parcellations being fully distinct. We report empirical results that strongly suggest that visual awareness is based on a partition in bulges, which are mutually only weakly connected. Such a notion immediately explains why inverted reliefs or surfaces illuminated from below appear so different as to be mutually not recognizable. PMID:27551359

  5. 5. Photocopy of print (original in Benson Lossing's Pictorial Field ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. Photocopy of print (original in Benson Lossing's Pictorial Field Book of the Revolution, p. 48) 1851 VIEW OF HOUSE IN 1848 (ILLUSTRATIONS AT TOP AND LOWER RIGHT) - John Neilson House, Bemis Heights, Stillwater, NY

  6. Upland Farmers' Comprehension of Pictorial Messages on Environmental Protection.

    ERIC Educational Resources Information Center

    Gravoso, R. S.; Stuart, T. H.

    2000-01-01

    A study to explore Filipino farmers' comprehension of pictorial messages on environmental protection found that educational attainment, visual exposure, and knowledge of environmental protection positively influenced visual comprehension. Color did not necessarily improve comprehension. (Contains 24 references.) (JOW)

  7. Breast dosimetry in clinical mammography

    NASA Astrophysics Data System (ADS)

    Benevides, Luis Alberto Do Rego

    The objective of this study was show that a clinical dosimetry protocol that utilizes a dosimetric breast phantom series based on population anthropometric measurements can reliably predict the average glandular dose (AGD) imparted to the patient during a routine screening mammogram. In the study, AGD was calculated using entrance skin exposure and dose conversion factors based on fibroglandular content, compressed breast thickness, mammography unit parameters and modifying parameters for homogeneous phantom (phantom factor), compressed breast lateral dimensions (volume factor) and anatomical features (anatomical factor). The protocol proposes the use of a fiber-optic coupled (FOCD) or Metal Oxide Semiconductor Field Effect Transistor (MOSFET) dosimeter to measure the entrance skin exposure at the time of the mammogram without interfering with diagnostic information of the mammogram. The study showed that FOCD had sensitivity with less than 7% energy dependence, linear in all tube current-time product stations, and was reproducible within 2%. FOCD was superior to MOSFET dosimeter in sensitivity, reusability, and reproducibility. The patient fibroglandular content was evaluated using a calibrated modified breast tissue equivalent homogeneous phantom series (BRTES-MOD) designed from anthropomorphic measurements of a screening mammography population and whose elemental composition was referenced to International Commission on Radiation Units and Measurements Report 44 tissues. The patient fibroglandular content, compressed breast thickness along with unit parameters and spectrum half-value layer were used to derive the currently used dose conversion factor (DgN). The study showed that the use of a homogeneous phantom, patient compressed breast lateral dimensions and patient anatomical features can affect AGD by as much as 12%, 3% and 1%, respectively. The protocol was found to be superior to existing methodologies. In addition, the study population anthropometric

  8. Mammography calibration qualities establishment in a Mo- Mo clinical system

    NASA Astrophysics Data System (ADS)

    Corrêa, E. L.; dos Santos, L. R.; Vivolo, V.; Potiens, M. P. A.

    2016-07-01

    In this study the mammography calibration qualities were established in a clinical mammography system. The objective is to provide the IPEN instruments calibration laboratory with both mammography calibration methods (using a clinical and an industrial system). The results showed a good behavior of mammography equipment, in terms of kVp, PPV and exposure time. The additional filtration of molybdenum is adequate, air-kerma rates were determined and spectra were obtained.

  9. Essays in applied economics

    NASA Astrophysics Data System (ADS)

    Arano, Kathleen

    Three independent studies in applied economics are presented. The first essay looks at the US natural gas industrial sector and estimates welfare effects associated with the changes in natural gas regulatory policy over the past three decades. Using a disequilibrium model suited to the natural gas industry, welfare transfers and deadweight losses are calculated. Results indicate that deregulation policies, beginning with the NGPA of 1978, have caused the industry to become more responsive to market conditions. Over time, regulated prices converge toward the estimated equilibrium prices. As a result of this convergence, deadweight losses associated with regulation are also diminished. The second essay examines the discounted utility model (DU), the standard model used for intertemporal decision-making. Prior empirical studies challenge the descriptive validity of the model. This essay addresses the four main inconsistencies that have been raised: domain dependence, magnitude effects, time effects, and gain/loss asymmetries. These inconsistencies, however, may be the result of the implicit assumption of linear utility and not a failure of the DU model itself. In order to test this hypothesis, data was collected from in-class surveys of economics classes at Mississippi State University. A random effects model for panel data estimation which accounts for individual specific effects was then used to impute discount rates measured in terms of dollars and utility. All four inconsistencies were found to be present when the dollar measures were used. Using utility measures of the discount rate resolved the inconsistencies in some cases. The third essay brings together two perspectives in the study of religion and economics: modeling religious behavior using economic tools and variables, and modeling economic behavior using religious variables. A system of ordered probit equations is developed to simultaneously model religious activities and economic outcomes. Using data

  10. Essays on strategy VII

    SciTech Connect

    Gill, T.C.

    1990-01-01

    Revolutionary developments in Europe and their global reverberations since 1989 have affected certain aspects of our national strategy. This volume presents nine essays dealing imaginatively with the issues of the post-Cold War period. One of them addresses general US strategy for the 1990s. Three focus on high-level strategic matters: the future of flexible response, antisatellite weapons, and forward, mobile defenses. The others address US chemical weapons policy, use of civilian aircraft for defense airlift, neutrality of the Panama Canal after 1999, arms sales by China, and strategic defense at reduced cost.

  11. Three Essays on Macroeconomics

    NASA Astrophysics Data System (ADS)

    Doda, Lider Baran

    This dissertation consists of three independent essays in macroeconomics. The first essay studies the transition to a low carbon economy using an extension of the neoclassical growth model featuring endogenous energy efficiency, exhaustible energy and explicit climate-economy interaction. I derive the properties of the laissez faire equilibrium and compare them to the optimal allocations of a social planner who internalizes the climate change externality. Three main results emerge. First, the exhaustibility of energy generates strong market based incentives to improve energy efficiency and reduce CO 2 emissions without any government intervention. Second, the market and optimal allocations are substantially different suggesting a role for the government. Third, high and persistent taxes are required to implement the optimal allocations as a competitive equilibrium with taxes. The second essay focuses on coal fired power plants (CFPP) - one of the largest sources of CO2 emissions globally - and their generation efficiency using a macroeconomic model with an embedded CFPP sector. A key feature of the model is the endogenous choice of production technologies which differ in their energy efficiency. After establishing four empirical facts about the CFPP sector, I analyze the long run quantitative effects of energy taxes. Using the calibrated model, I find that sector-specific coal taxes have large effects on generation efficiency by inducing the use of more efficient technologies. Moreover, such taxes achieve large CO2 emissions reductions with relatively small effects on consumption and output. The final essay studies the procyclicality of fiscal policy in developing countries, which is a well-documented empirical observation seemingly at odds with Neoclassical and Keynesian policy prescriptions. I examine this issue by solving the optimal fiscal policy problem of a small open economy government when the interest rates on external debt are endogenous. Given an

  12. Essays on Strategy VIII

    DTIC Science & Technology

    1991-01-01

    TRATEG o DTIC CV) ELECTEV Hil MAY 14 19 S E ST lwpoe orpbi e Ditibf t1J~ham ESSAYS ON STRATEGY Acceýioo For INTIS CRA& DT IJJC J A1 U d.iýou;4ýced...tion are primary tools in the economic portfolios of many nations, both friends and foes. According to Senator David Boren, chairman of the Senate Select...w New York Times, 16 March 1990, p. A35. 2. David Boren, US Senator, speech before the National Press Club, 3 April 1990. Transcript furnished by

  13. Grid infrastructures for developing mammography CAD systems.

    PubMed

    Ramos-Pollan, Raul; Franco, Jose M; Sevilla, Jorge; Guevara-Lopez, Miguel A; de Posada, Naimy Gonzalez; Loureiro, Joanna; Ramos, Isabel

    2010-01-01

    This paper presents a set of technologies developed to exploit Grid infrastructures for breast cancer CAD, that include (1) federated repositories of mammography images and clinical data over Grid storage, (2) a workstation for mammography image analysis and diagnosis and (3) a framework for data analysis and training machine learning classifiers over Grid computing power specially tuned for medical image based data. An experimental mammography digital repository of approximately 300 mammograms from the MIAS database was created and classifiers were built achieving a 0.85 average area under the ROC curve in a dataset of 100 selected mammograms with representative pathological lesions and normal cases. Similar results were achieved with classifiers built for the UCI Breast Cancer Wisconsin dataset (699 features vectors). Now these technologies are being validated in a real medical environment at the Faculty of Medicine in Porto University after a process of integrating the tools within the clinicians workflows and IT systems.

  14. Elasto-Mammography: Elastic Property Reconstruction in Breast Tissues

    SciTech Connect

    Wang, Z. G.; Liu, Y.; Wang, G.; Sun, L. Z.

    2008-02-15

    Mammography is the primary method for screening and detecting breast cancers. However, it frequently fails to detect small tumors and is not quite specific in terms of tumor benignity and malignancy. The objective of this paper is to develop a new imaging modality called elasto-mammography that generates the modulus elastograms based on conventional mammographs. A new elastic reconstruction method is described based on elastography and mammography for breast tissues. Elastic distribution can be reconstructed through the measurement of displacement provided by mammographic projection. It is shown that the proposed elasto-mammography provides higher sensitivity and specificity than the conventional mammography on its own for breast cancer diagnosis.

  15. Pain with mammography: fact or fiction?

    PubMed

    Nielsen, B; Miaskowski, C; Dibble, S L

    1993-05-01

    This article presents an overview of current knowledge about mammography-related pain and discomfort. Possible causes of pain and discomfort are discussed along with the results of two pilot studies that investigated the prevalence and severity of pain and discomfort associated with film-screen mammograms in a mobile screening program. Based on these studies, the authors conclude that pain is a problem for a significant number of women from diverse ethnic and socioeconomic backgrounds. A nursing care plan is provided to assist nurses in reducing mammography-related pain and discomfort.

  16. Identifying Sociocultural Barriers to Mammography Adherence Among Appalachian Kentucky Women

    PubMed Central

    Cohen, Elisia L.; Wilson, Bethney R.; Vanderpool, Robin C.; Collins, Tom

    2016-01-01

    Despite lower breast cancer incidence rates, Appalachian women evidence lower frequency of screening mammography and higher mortality risk for breast cancer compared to non-Appalachian women in Kentucky, and in the United States, overall. Utilizing data from 27 in-depth interviews from women in seven Appalachian Kentucky counties, this study examines how Appalachian women explain sociocultural barriers and facilitators to timely screening mammography, and explores their common narratives about their mammography experiences. The women describe how pain and embarrassment, less personal and less professional mammography experiences, cancer fears, and poor provider communication pose barriers to timely and appropriate mammography schedule adherence and follow-up care. The study also identifies how improving communication strategies in the mammography encounter may improve mammography experiences and adherence to screening guidelines. PMID:25668682

  17. Identifying Sociocultural Barriers to Mammography Adherence Among Appalachian Kentucky Women.

    PubMed

    Cohen, Elisia L; Wilson, Bethney R; Vanderpool, Robin C; Collins, Tom

    2016-01-01

    Despite lower breast cancer incidence rates, Appalachian women evidence lower frequency of screening mammography and higher mortality risk for breast cancer compared to non-Appalachian women in Kentucky, and in the United States, overall. Utilizing data from 27 in-depth interviews from women in seven Appalachian Kentucky counties, this study examines how Appalachian women explain sociocultural barriers and facilitators to timely screening mammography, and explores their common narratives about their mammography experiences. The women describe how pain and embarrassment, less personal and less professional mammography experiences, cancer fears, and poor provider communication pose barriers to timely and appropriate mammography schedule adherence and follow-up care. The study also identifies how improving communication strategies in the mammography encounter may improve mammography experiences and adherence to screening guidelines.

  18. Access to Mammography Facilities and Detection of Breast Cancer by Screening Mammography: A GIS Approach.

    PubMed

    Rahman, Selina; Price, James H; Dignan, Mark; Rahman, Saleh; Lindquist, Peter S; Jordan, Timothy R

    2009-01-01

    OBJECTIVES: The objective of the study was to examine the association between access to mammography facilities and utilization of screening mammography in an urban population. METHODS: Data on female breast cancer cases were obtained from an extensive mammography surveillance project. Distance to mammography facilities was measured by using GIS, which was followed by measuring geographical access to mammography facilities using Floating Catchment Area (FCA) method (considering all available facilities within an arbitrary radius from the woman's residence by using Arc GIS 9.0 software). RESULTS: Of 2,024 women, 91.4% were Caucasian; age ranged from 25 to 98 years; most (95%) were non-Hispanic in origin. Logistic regression found age, family history, hormone replacement therapy, physician recommendation, and breast cancer stage at diagnosis to be significant predictors of having had a previous mammogram. Women having higher access to mammography facilities were less likely to have had a previous mammogram compared to women who had low access, considering all the facilities within 10 miles (OR=0.41, CI=0.22-0.76), 30 miles (OR=0.52, CI=0.29-0.91) and 40 miles (OR=0.51, CI=0.28-0.92) radiuses. CONCLUSIONS: Physical distance to mammography facilities does not necessarily predict utilization of mammogram and greater access does not assure greater utilizations, due to constraints imposed by socio economic and cultural barriers. Future studies should focus on measuring access to mammography facilities capturing a broader dimension of access considering qualitative aspect of facilities, as well as other travel impedances.

  19. Pictorial communication in virtual and real environments

    NASA Technical Reports Server (NTRS)

    Ellis, Stephen R. (Editor)

    1991-01-01

    Papers about the communication between human users and machines in real and synthetic environments are presented. Individual topics addressed include: pictorial communication, distortions in memory for visual displays, cartography and map displays, efficiency of graphical perception, volumetric visualization of 3D data, spatial displays to increase pilot situational awareness, teleoperation of land vehicles, computer graphics system for visualizing spacecraft in orbit, visual display aid for orbital maneuvering, multiaxis control in telemanipulation and vehicle guidance, visual enhancements in pick-and-place tasks, target axis effects under transformed visual-motor mappings, adapting to variable prismatic displacement. Also discussed are: spatial vision within egocentric and exocentric frames of reference, sensory conflict in motion sickness, interactions of form and orientation, perception of geometrical structure from congruence, prediction of three-dimensionality across continuous surfaces, effects of viewpoint in the virtual space of pictures, visual slant underestimation, spatial constraints of stereopsis in video displays, stereoscopic stance perception, paradoxical monocular stereopsis and perspective vergence. (No individual items are abstracted in this volume)

  20. Essay Reliability: Form and Meaning.

    ERIC Educational Resources Information Center

    Shale, Doug

    This study is an attempt at a cohesive characterization of the concept of essay reliability. As such, it takes as a basic premise that previous and current practices in reporting reliability estimates for essay tests have certain shortcomings. The study provides an analysis of these shortcomings--partly to encourage a fuller understanding of the…

  1. The mammography project at the SYRMEP beamline.

    PubMed

    Dreossi, D; Abrami, A; Arfelli, F; Bregant, P; Casarin, K; Chenda, V; Cova, M A; Longo, R; Menk, R-H; Quai, E; Quaia, E; Rigon, L; Rokvic, T; Sanabor, D; Tonutti, M; Tromba, G; Vascotto, A; Zanconati, F; Castelli, E

    2008-12-01

    A clinical program for X-ray phase contrast (PhC) mammography with synchrotron radiation (SR) has been started in March 2006 at the SYRMEP beamline of Elettra, the SR facility in Trieste, Italy. The original beamline layout has been modified substantially and a clinical facility has been realized. In order to fulfill all security requirements, dedicated systems have been designed and implemented, following redundancy criteria and "fail safe" philosophy. Planar radiographic images are obtained by scanning simultaneously the patient and the detector through the stationary and laminar SR beam. In this first phase of the project a commercial screen-film system has been used as image receptor. Upon approval by the respective authorities, the mammography program is about half way to conclusion. Up to now about 50 patients have been examined. The patients are volunteers recruited by the radiologist after conventional examinations at the hospital resulted in an uncertain diagnosis. As an example one case of PhC SR mammography is shown and compared to conventional digital mammography. Preliminary analysis shows the high diagnostic quality of the PhC SR images that were acquired with equal or less delivered dose compared to the conventional ones.

  2. Beyond the mammography debate: a moderate perspective.

    PubMed

    Kaniklidis, C

    2015-06-01

    After some decades of contention, one can almost despair and conclude that (paraphrasing) "the mammography debate you will have with you always." Against that sentiment, in this review I argue, after reflecting on some of the major themes of this long-standing debate, that we must begin to move beyond the narrow borders of claim and counterclaim to seek consensus on what the balance of methodologically sound and critically appraised evidence demonstrates, and also to find overlooked underlying convergences; after acknowledging the reality of some residual and non-trivial harms from mammography, to promote effective strategies for harm mitigation; and to encourage deployment of new screening modalities that will render many of the issues and concerns in the debate obsolete. To these ends, I provide a sketch of what this looking forward and beyond the current debate might look like, leveraging advantages from abbreviated breast magnetic resonance imaging technologies (such as the ultrafast and twist protocols) and from digital breast tomosynthesis-also known as three-dimensional mammography. I also locate the debate within the broader context of mammography in the real world as it plays out not for the disputants, but for the stakeholders themselves: the screening-eligible patients and the physicians in the front lines who are charged with enabling both the acts of screening and the facts of screening at their maximally objective and patient-accessible levels to facilitate informed decisions.

  3. Beyond the mammography debate: a moderate perspective

    PubMed Central

    Kaniklidis, C

    2015-01-01

    After some decades of contention, one can almost despair and conclude that (paraphrasing) “the mammography debate you will have with you always.” Against that sentiment, in this review I argue, after reflecting on some of the major themes of this long-standing debate, that we must begin to move beyond the narrow borders of claim and counterclaim to seek consensus on what the balance of methodologically sound and critically appraised evidence demonstrates, and also to find overlooked underlying convergences; after acknowledging the reality of some residual and non-trivial harms from mammography, to promote effective strategies for harm mitigation; and to encourage deployment of new screening modalities that will render many of the issues and concerns in the debate obsolete. To these ends, I provide a sketch of what this looking forward and beyond the current debate might look like, leveraging advantages from abbreviated breast magnetic resonance imaging technologies (such as the ultrafast and twist protocols) and from digital breast tomosynthesis—also known as three-dimensional mammography. I also locate the debate within the broader context of mammography in the real world as it plays out not for the disputants, but for the stakeholders themselves: the screening-eligible patients and the physicians in the front lines who are charged with enabling both the acts of screening and the facts of screening at their maximally objective and patient-accessible levels to facilitate informed decisions. PMID:26089721

  4. Physical measures of image quality in mammography

    NASA Astrophysics Data System (ADS)

    Chakraborty, Dev P.

    1996-04-01

    A recently introduced method for quantitative analysis of images of the American College of Radiology (ACR) mammography accreditation phantom has been extended to include signal- to-noise-ratio (SNR) measurements, and has been applied to survey the image quality of 54 mammography machines from 17 hospitals. Participants sent us phantom images to be evaluated for each mammography machine at their hospital. Each phantom was loaned to us for obtaining images of the wax insert plate on a reference machine at our institution. The images were digitized and analyzed to yield indices that quantified the image quality of the machines precisely. We have developed methods for normalizing for the variation of the individual speck sizes between different ACR phantoms, for the variation of the speck sizes within a microcalcification group, and for variations in overall speeds of the mammography systems. In terms of the microcalcification SNR, the variability of the x-ray machines was 40.5% when no allowance was made for phantom or mAs variations. This dropped to 17.1% when phantom variability was accounted for, and to 12.7% when mAs variability was also allowed for. Our work shows the feasibility of practical, low-cost, objective and accurate evaluations, as a useful adjunct to the present ACR method.

  5. Screening Mammography in Older Women: A Review

    PubMed Central

    Walter, Louise C.; Schonberg, Mara A.

    2015-01-01

    Importance Guidelines recommend individualizing screening mammography decisions for women 75 and older. However, little pragmatic guidance is available to inform this approach. Objective To provide an evidence-based approach to individualizing decision-making about screening mammography that considers older women's risk of breast cancer and the potential benefits and harms of screening in the context of varying life expectancies and preferences. Evidence Acquisition We searched PubMed for English-language studies in peer-reviewed journals published from January 1, 1990 to February 1, 2014 to identify risk factors for late-life breast cancer in women 65 and older and to quantify the benefits and harms of screening mammography for women 75 and older. Findings Age is the major risk factor for late-life breast cancer. In general, traditional breast cancer risk factors (e.g., age at first birth, age at menarche) that represent hormonal exposures in the distant past are less predictive of late-life breast cancer than factors indicating recent exposure to endogenous hormones (e.g., bone mass, obesity). None of the randomized trials of screening mammography included women over age 74, such that it is uncertain whether screening mammography is beneficial in these women. Observational data favor extending screening mammography to older women who have a life expectancy > 5-10 years. Modeling studies suggest approximately 2 fewer women per 1,000 die from breast cancer if women in their 70's continue biennial screening for 10 years, versus stopping screening at age 69. Potential benefits must be weighed with potential harms of continued screening over ten years, which include false-positive mammograms (~200 per 1,000 women screened) and overdiagnosis (~13 per 1,000 women screened). Providing these frequencies both verbally and graphically may help inform older women's decision-making. Conclusions and Relevance For women with less than a 5-10 year life expectancy

  6. The Effectiveness of Textbook, Student Generated, and Pictorial Versions of Presenting Mathematical Problems.

    ERIC Educational Resources Information Center

    Kulm, Gerald; And Others

    The study sought to determine the relationship between problem solving ability and problem presentation stimuli of textbook (T), student generated (S), pictorial (P), textbook and pictorial (TP), and student generated and pictorial (SP). Ten problems for each stimulus were presented to ninth grade algebra students randomly assigned within IQ…

  7. 2D vs. 3D mammography observer study

    NASA Astrophysics Data System (ADS)

    Fernandez, James Reza F.; Hovanessian-Larsen, Linda; Liu, Brent

    2011-03-01

    Breast cancer is the most common type of non-skin cancer in women. 2D mammography is a screening tool to aid in the early detection of breast cancer, but has diagnostic limitations of overlapping tissues, especially in dense breasts. 3D mammography has the potential to improve detection outcomes by increasing specificity, and a new 3D screening tool with a 3D display for mammography aims to improve performance and efficiency as compared to 2D mammography. An observer study using a mammography phantom was performed to compare traditional 2D mammography with this ne 3D mammography technique. In comparing 3D and 2D mammography there was no difference in calcification detection, and mass detection was better in 2D as compared to 3D. There was a significant decrease in reading time for masses, calcifications, and normals in 3D compared to 2D, however, as well as more favorable confidence levels in reading normal cases. Given the limitations of the mammography phantom used, however, a clearer picture in comparing 3D and 2D mammography may be better acquired with the incorporation of human studies in the future.

  8. Essays in applied microeconomics

    NASA Astrophysics Data System (ADS)

    Davis, Lucas William

    2005-11-01

    The first essay measures the impact of an outbreak of pediatric leukemia on local housing values. A model of residential location choice is used to describe conditions under which the gradient of the hedonic price function with respect to health risk is equal to household marginal willingness to pay to avoid pediatric leukemia risk. This equalizing differential is estimated using property-level sales records from a county in Nevada where residents have recently experienced a severe increase in pediatric leukemia. Housing values are compared before and after the increase with a nearby county acting as a control group. The results indicate that housing values decreased 15.6% during the period of maximum risk. Results are similar for alternative measures of risk and across houses of different sizes. With risk estimates derived using a Bayesian learning model the results imply a statistical value of pediatric leukemia of $5.6 million. The results from the paper provide some of the first market-based estimates of the value of health for children. The second essay evaluates the cost-effectiveness of public incentives that encourage households to purchase high-efficiency durable goods. The demand for durable goods and the demand for energy and other inputs are modeled jointly as the solution to a household production problem. The empirical analysis focuses on the case of clothes washers. The production technology and utilization decision are estimated using household-level data from field trials in which participants received front-loading clothes washers free of charge. The estimation strategy exploits this quasi-random replacement of washers to derive robust estimates of the utilization decision. The results indicate a price elasticity, -.06, that is statistically different from zero across specifications. The parameters from the utilization decision are used to estimate the purchase decision using data from the Consumer Expenditure Survey, 1994-2002. Households

  9. Teaching Science Through Pictorial Models During Read-Alouds

    NASA Astrophysics Data System (ADS)

    Oliveira, Alandeom W.; Rivera, Seema; Glass, Rory; Mastroianni, Michael; Wizner, Francine; Amodeo, Vincent

    2013-03-01

    This study examines how three elementary teachers refer to pictorial models (photographs, drawings, and cartoons) during science read-alouds. While one teacher used realistic photographs for the purpose of visually verifying facts about crystals, another employed analytical diagrams as heuristic tools to help students visualize complex target systems (rainbow formation and human eye functioning). Another teacher used fictional cartoons to engage students in analogical storytelling, communicating animal camouflage as analogous to human "blending in." However, teachers did not always explicitly convey the representational nature of pictorial models (analog and target as separate entities). It is argued that teachers need to become more aware of how they refer to pictorial models in children's science books and how to promote student visual literacy.

  10. Sobre el estado evolutivo de β Pictoris

    NASA Astrophysics Data System (ADS)

    Brunini, A.; Benvenuto, O. G.

    Desde el descubrimiento de fuertes excesos infrarrojos en β Pictoris, esta estrella ha sido muy estudiada y es considerada candidata a poseer un sistema planetario propio. β Pic está rodeada de un disco asimétrico de polvo que se observa de canto y que esta vacío a distancias <= 40 AU. Esto se considera una fuerte evidencia en favor de la presencia de (al menos) un planeta gigante. Recientemente se han observado líneas de material circunestelar que se han interpretado como consecuencia de la caída de objetos cometarios sobre esta estrella. Recientemente se ha utilizado la existencia del disco de polvo para atribuir una edad corta (pre - secuencia principal) a βPic. Sin embargo, la evaporación de estos cometas provee suficiente polvo como para explicar la presencia del disco observado sin necesidad de edades cortas. En este trabajo mostramos que la comparación entre la tasa de impactos cometarios estimada en el Sistema Solar para diferentes etapas de su evolución y los datos observados en β Pic indica edades avanzadas para β Pic. Esta estimación debe tomarse con cautela ya que depende de la estructura de los sistemas planetarios. Además mostramos que, desde el punto de vista de la evolución estelar y con las incertezas presentes en la luminosidad y la temperatura efectiva, existe un continuo de edades posible para β Pic. Sin embargo, empleando los datos provenientes de los flujos cometarios encontramos que una edad prolongada es consistente con ambos tratamientos.

  11. 76 FR 60848 - National Mammography Quality Assurance Advisory Committee; Notice of Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-30

    ... HUMAN SERVICES Food and Drug Administration National Mammography Quality Assurance Advisory Committee... be open to the public. Name of Committee: National Mammography Quality Assurance Advisory Committee...) Proposed changes to the Mammography Quality Standard Act (MQSA) policies and inspection procedures;...

  12. Teaching Students with Severe Intellectual Disabilities Non-Representational Art Using a New Pictorial and Musical Programme.

    ERIC Educational Resources Information Center

    Riddoch, Jane V.; Waugh, Russell F.

    2003-01-01

    A recently developed pictorial and musical program was used to teach abstract art to 12 elementary students with severe intellectual disabilities and 12 controls. There was a significant main instructional effect favoring pictorial with classical music over both pictorial only and pictorial with rock music. (Contains references.) (Author/CR)

  13. Mammography-oncogenecity at low doses.

    PubMed

    Heyes, G J; Mill, A J; Charles, M W

    2009-06-01

    Controversy exists regarding the biological effectiveness of low energy x-rays used for mammography breast screening. Recent radiobiology studies have provided compelling evidence that these low energy x-rays may be 4.42 +/- 2.02 times more effective in causing mutational damage than higher energy x-rays. These data include a study involving in vitro irradiation of a human cell line using a mammography x-ray source and a high energy source which matches the spectrum of radiation observed in survivors from the Hiroshima atomic bomb. Current radiation risk estimates rely heavily on data from the atomic bomb survivors, and a direct comparison between the diagnostic energies used in the UK breast screening programme and those used for risk estimates can now be made. Evidence highlighting the increase in relative biological effectiveness (RBE) of mammography x-rays to a range of x-ray energies implies that the risks of radiation-induced breast cancers for mammography x-rays are potentially underestimated by a factor of four. A pooled analysis of three measurements gives a maximal RBE (for malignant transformation of human cells in vitro) of 4.02 +/- 0.72 for 29 kVp (peak accelerating voltage) x-rays compared to high energy electrons and higher energy x-rays. For the majority of women in the UK NHS breast screening programme, it is shown that the benefit safely exceeds the risk of possible cancer induction even when this higher biological effectiveness factor is applied. The risk/benefit analysis, however, implies the need for caution for women screened under the age of 50, and particularly for those with a family history (and therefore a likely genetic susceptibility) of breast cancer. In vitro radiobiological data are generally acquired at high doses, and there are different extrapolation mechanisms to the low doses seen clinically. Recent low dose in vitro data have indicated a potential suppressive effect at very low dose rates and doses. Whilst mammography is a low

  14. Preventing the pack size effect: exploring the effectiveness of pictorial and non-pictorial serving size recommendations.

    PubMed

    Versluis, Iris; Papies, Esther K; Marchiori, David

    2015-04-01

    People eat more from large than from small packs, which is known as the pack size effect. We hypothesized that providing a serving size recommendation would reduce the influence of the pack size on consumption and would thus diminish the pack size effect. Moreover, we hypothesized that a pictorial serving size recommendation, displaying food amounts visually, would be more effective than a non-pictorial recommendation that communicates the recommended amount in grams only. We tested these hypotheses in two online experiments (N = 317 and N = 324) and in one lab experiment (N = 89). In the online experiments, participants were shown a small or a large pack of unhealthy snacks, with or without a serving size recommendation. The main outcome measure was expected consumption. Replicating the pack size effect in an online setting, we found that participants expected to consume more food from large than from small packs. Furthermore, the pack size effect was considerably stronger for men than for women. Importantly, when including portion size preferences as a covariate, the pictorial serving size recommendation significantly reduced expected consumption, especially when placed on a large pack, as hypothesized. The non-pictorial serving size recommendation had no effect. In the lab experiment, students received a large bag of M&M's which did or did not contain the pictorial serving size recommendation. We again included general portion size preferences as a covariate. The serving size recommendation significantly lowered the amount of M&M's that participants served themselves, but only when participants reported to have noticed the serving size recommendation. We conclude that providing a pictorial serving size recommendation can be an effective intervention strategy to reduce the pack size effect, if it attracts sufficient attention.

  15. Safety signs on agricultural machinery: Pictorials do not always successfully convey their messages to target users.

    PubMed

    Caffaro, Federica; Mirisola, Alberto; Cavallo, Eugenio

    2017-01-01

    This study investigated the extent to which a sample of Italian users comprehended safety pictorials used on agricultural machinery. A questionnaire with 12 safety pictorials was administered to 248 users of agricultural machinery. For each of the pictorials, the participants were asked to select the most appropriate description of four written choices. The investigated safety pictorials were, in general, not well comprehended. Two different classes of participants were identified, each with a different level of comprehension. The participants with better comprehension were characterized by the regular use of agricultural machinery and frequent previous exposure to pictorials. The need for training courses focusing on safety pictorials and their meanings, as well as the need for improvement to the pictorials themselves to make them more easily comprehended, is discussed.

  16. Optimization of Image Quality and Dose in Digital Mammography.

    PubMed

    Fausto, Agnes M F; Lopes, M C; de Sousa, M C; Furquim, Tânia A C; Mol, Anderson W; Velasco, Fermin G

    2017-04-01

    Nowadays, the optimization in digital mammography is one of the most important challenges in diagnostic radiology. The new digital technology has introduced additional elements to be considered in this scenario. A major goal of mammography is related to the detection of structures on the order of micrometers (μm) and the need to distinguish the different types of tissues, with very close density values. The diagnosis in mammography faces the difficulty that the breast tissues and pathological findings have very close linear attenuation coefficients within the energy range used in mammography. The aim of this study was to develop a methodology for optimizing exposure parameters of digital mammography based on a new Figure of Merit: FOM ≡ (IQFinv)(2)/AGD, considering the image quality and dose. The study was conducted using the digital mammography Senographe DS/GE, and CDMAM and TORMAM phantoms. The characterization of clinical practice, carried out in the mammography system under study, was performed considering different breast thicknesses, the technical parameters of exposure, and processing options of images used by the equipment's automatic exposure system. The results showed a difference between the values of the optimized parameters and those ones chosen by the automatic system of the mammography unit, specifically for small breast. The optimized exposure parameters showed better results than those obtained by the automatic system of the mammography, for the image quality parameters and its impact on detection of breast structures when analyzed by radiologists.

  17. Time perspective and perceived risk as related to mammography screening.

    PubMed

    Griva, Fay; Anagnostopoulos, Fotios; Potamianos, Gregory

    2013-01-01

    The present study explored the relation of time perspective to perceived risk for breast cancer and mammography screening. Women free from breast cancer (N = 194), eligible for mammography screening in terms of age, completed the Zimbardo Time Perspective Inventory (Zimbardo & Boyd, 1999) and measures of perceived risk, attitude toward performing mammography screening, intention to get a mammogram, and mammography screening behavior. Hierarchical multiple regression analysis revealed that perceived risk of breast cancer (β= .18, p < .01) and intention to be screened (β = .35, p < .01) were significantly associated with mammography screening, after controlling for the effects of sociodemographic (e.g., age, education, and economic level) and health-related variables (e.g., family history of breast cancer and previous benign breast disease). Path analyses including the main psychological variables indicated that perceived risk was indirectly related to intention via attitude (β = .17, p < .01), and to mammography screening through attitude and intention (β = .06, p < .01). Attitude was indirectly related to mammography screening via intention (β = .20, p < .01). Also, a significant indirect association was observed between future orientation and mammography screening, via perceived risk (β = .10, p < .01). Theoretical implications of study findings and suggestions for future research on use of mammography are presented.

  18. Digital Mammography: Improvements in Breast Cancer Diagnostic

    NASA Astrophysics Data System (ADS)

    Montaño Zetina, Luis Manuel

    2006-01-01

    X-ray mammography is the most sensitive imaging technique for early detection of breast cancer (diagnostics). It is performed by a radiological system equipped with a rotating molybdenum (Mo) anode tube with an additional Mo filter. In the production of X-ray, bremsstrahlung photons produce an intense diffuse radiation, affecting the contrast between normal and cancerous tissue. So it is known that a good mammographic imaging can help to detect cancer in the first stages avoiding surgery, amputation or even death. In the last years there has been some developments in new imaging techniques to improve the contrast spatial resolution between different tissues: digital imaging, or the so call digital mammography. Digital mammographic imaging is considered an improvement in the prevention of breast cancer due to the advantages it offers.

  19. Digital Mammography: Improvements in Breast Cancer Diagnostic

    SciTech Connect

    Montano Zetina, Luis Manuel

    2006-01-06

    X-ray mammography is the most sensitive imaging technique for early detection of breast cancer (diagnostics). It is performed by a radiological system equipped with a rotating molybdenum (Mo) anode tube with an additional Mo filter. In the production of X-ray, bremsstrahlung photons produce an intense diffuse radiation, affecting the contrast between normal and cancerous tissue. So it is known that a good mammographic imaging can help to detect cancer in the first stages avoiding surgery, amputation or even death. In the last years there has been some developments in new imaging techniques to improve the contrast spatial resolution between different tissues: digital imaging, or the so call digital mammography. Digital mammographic imaging is considered an improvement in the prevention of breast cancer due to the advantages it offers.

  20. A glass-ceramic plate for mammography.

    SciTech Connect

    Johnson, J. A.; Schweizer, S.; Lubinsky, A. R.; Nuclear Engineering Division; Univ. of Paderborn; State Univ. of New York at Stony Brook

    2007-01-01

    We developed translucent glass-ceramic image plates for digital mammography. The glass ceramics are based on europium-doped fluorozirconate glasses, which were additionally doped with chlorine to initiate the nucleation of barium chloride nanoparticles therein. The X-ray image is stored in the form of stable electron-hole pairs, which can be read out afterwards with a scanning laser beam in a 'photostimulated luminescence' (PSL) process. Measurements of the required stimulating exposure, integrated PSL signal, and optical light spreading of the stimulating laser light were performed to allow projection of the detective quantum efficiency (DQE) for the proposed X-ray storage phosphor system. The projected DQE is compared with commercially available electronic mammography systems.

  1. Discrepancies between film and digital mammography interpretations

    NASA Astrophysics Data System (ADS)

    Malhotra, Poonam; Kallergi, Maria; Alexander, Dominik; Berman, Claudia G.; Gardner, Mary; Hersh, Marla R.; Hooper, Lisa; Kim, Jihai J.; Venugopal, Priya

    2002-04-01

    The purpose of this study was to evaluate the frequency and reasons of disagreement between film and full-field digital mammography (FFDM) interpretations observed in a prospective clinical trial performed with the GE Senographe 2000D system. The data from 643 mammography examinations comprising both digital and film mammograms were analyzed for this purpose. Reports indicated that 455 findings were identified on the digital softcopy reading and 457 findings on the standard film mammography with 408 discrepancies. Findings with discrepancies were matched and analyzed. A reason was identified and a relative conspicuity score of 0 to 10 was assigned to each finding at the time of resolution; 0 corresponded to a finding highly conspicuous on digital, 10 to a finding highly conspicuous on film, and 5 denoted equal visibility on both. After review, agreement was established between the two modalities in 73.3% of the findings; 13.5% of findings were seen better on digital and 13.2% of the findings were seen better on film. Approximately 63% of the discrepancies occurred due to variability in the reporting style of the radiologists and/or unavailability of prior films for comparison. Three cancer cases were identified in this study; two were seen on both modalities and one only on film. In conclusion, no statistically significant differences were observed between digital and film mammography, a result that despite the small size of our dataset is in agreement with previous reports. Inter-observer variability, display differences, and presentation disagreements are the main reasons for interpretation differences that are primarily identified in the classification and BIRADS assignment.

  2. Computer vision and artificial intelligence in mammography.

    PubMed

    Vyborny, C J; Giger, M L

    1994-03-01

    The revolution in digital computer technology that has made possible new and sophisticated imaging techniques may next influence the interpretation of radiologic images. In mammography, computer vision and artificial intelligence techniques have been used successfully to detect or to characterize abnormalities on digital images. Radiologists supplied with this information often perform better at mammographic detection or characterization tasks in observer studies than do unaided radiologists. This technology therefore could decrease errors in mammographic interpretation that continue to plague human observers.

  3. Teaching Science through Pictorial Models during Read-Alouds

    ERIC Educational Resources Information Center

    Oliveira, Alandeom W.; Rivera, Seema; Glass, Rory; Mastroianni, Michael; Wizner, Francine; Amodeo, Vincent

    2013-01-01

    This study examines how three elementary teachers refer to pictorial models (photographs, drawings, and cartoons) during science read-alouds. While one teacher used realistic photographs for the purpose of visually verifying facts about crystals, another employed analytical diagrams as heuristic tools to help students visualize complex target…

  4. Pictorial keys to evaluate foliar injury caused by hydrogen fluoride

    SciTech Connect

    Granett, A.L.

    1982-08-01

    Pictorial keys were developed to aid graders in quantifying leaf injury on plants exposed to high concentrations of hydrogen fluoride gas. The keys were based on a pretransformed rating scale of 1 (no injury) to 12 (death of leaf). 5 references, 2 figures, 1 table.

  5. Responsiveness of Nigerian Students to Pictorial Depth Cues.

    ERIC Educational Resources Information Center

    Evans, G. S.; Seddon, G. M.

    1978-01-01

    Three groups of Nigerian high school and college students were tested for response to four pictorial depth cues. Students had more difficulty with cues concerning the relative size of objects and the foreshortening of straight lines than with cues involving overlap of lines and distortion of the angles between lines. (Author/JEG)

  6. Pictorial versus Verbal Rating Scales in Music Preference Measurement.

    ERIC Educational Resources Information Center

    LeBlanc, Albert; Jin, Young Chang; Simpson, Charles S.; Stamou, Lelouda; McCrary, Jan

    1998-01-01

    Compares pictorial and verbal rating scales as measures of music preference opinions. Examines internal consistency and test-retest reliability of each type of scale, the overall preference scores generated through the use of each to measure preference for the same music stimuli, and student preferences for each type after using them. (DSK)

  7. Imaging of Adult Ocular and Orbital Pathology - a Pictorial Review

    PubMed Central

    Grech, Reuben; Cornish, Kurt Spiteri; Galvin, Patrick Leo; Grech, Stephan; Looby, Seamus; O’Hare, Alan; Mizzi, Adrian; Thornton, John; Brennan, Paul

    2014-01-01

    Orbital pathology often presents a diagnostic challenge to the reporting radiologist. The aetiology is protean, and clinical input is therefore often necessary to narrow the differential diagnosis. With this manuscript, we provide a pictorial review of adult ocular and orbital pathology. PMID:24967016

  8. The Influence of Different Pictorial Representations during Idea Generation

    ERIC Educational Resources Information Center

    Cardoso, Carlos; Badke-Schaub, Petra

    2011-01-01

    During creative problem-solving, designers frequently come across a variety of rich visual displays. While browsing for different sources of information, pictorial representations of existing concepts take prominence. However, once designers start generating new solution ideas to design problems, they often become too attached to some of the…

  9. Essays in Applied Microeconomics

    NASA Astrophysics Data System (ADS)

    Ge, Qi

    This dissertation consists of three self-contained applied microeconomics essays on topics related to behavioral economics and industrial organization. Chapter 1 studies how sentiment as a result of sports event outcomes affects consumers' tipping behavior in the presence of social norms. I formulate a model of tipping behavior that captures consumer sentiment following a reference-dependent preference framework and empirically test its relevance using the game outcomes of the NBA and the trip and tipping data on New York City taxicabs. While I find that consumers' tipping behavior responds to unexpected wins and losses of their home team, particularly in close game outcomes, I do not find evidence for loss aversion. Coupled with the findings on default tipping, my empirical results on the asymmetric tipping responses suggest that while social norms may dominate loss aversion, affect and surprises can result in freedom on the upside of tipping. Chapter 2 utilizes a novel data source of airline entry and exit announcements and examines how the incumbent airlines adjust quality provisions as a response to their competitors' announcements and the role of timing in such responses. I find no evidence that the incumbents engage in preemptive actions when facing probable entry and exit threats as signaled by the competitors' announcements in either short term or long term. There is, however, evidence supporting their responses to the competitors' realized entry or exit. My empirical findings underscore the role of timing in determining preemptive actions and suggest that previous studies may have overestimated how the incumbent airlines respond to entry threats. Chapter 3, which is collaborated with Benjamin Ho, investigates the habit formation of consumers' thermostat setting behavior, an often implicitly made decision and yet a key determinant of home energy consumption and expenditures. We utilize a high frequency dataset on household thermostat usage and find that

  10. Essays in public economics

    NASA Astrophysics Data System (ADS)

    Seligman, Jason Scott

    2002-01-01

    Three essays in the field of public economics are included in this thesis. Chapter 1 begins this work with an introduction to public economics and places the remaining chapters in context. Like all economic agents, the government must manage its cash position. Chapter 2 considers this activity. Short-term financial requirements cause the government to solicit the market for bills not previously scheduled (Cash Management Bills). Using data from the US Treasury's Proprietary Domestic Finance Database, this chapter shows that these bills have higher costs than normal bills, suggesting that both Treasury and financial markets appreciate that demand is more inelastic for these instruments. In addition, this research identifies several factors that increase finance costs for Treasury in meeting short-term financial need. Chapter 3 explores location choices for generation investment in a re-regulated electricity market. Recently, there have been significant changes in the regulation of electricity in the State of California. These changes may affect generation investment behavior within the State, an important consideration for policy makers. This work identifies the impact of public sector regulatory change on private sector investment outcomes, by comparing the location and scope of electricity generation projects before and after two specific regulatory changes in air quality management and transmission tariff charges, while controlling for expected population growth patterns within the State. Significant changes in location preference are identified using factors for the northern and southern transmission zones, NP15 and SP15, the intermediate zone ZP26, and for areas outside of ISO control. Chapter 4 considers Disability Insurance and individual public pension investment accounts. Current debate on the Social Security Administration's long-term finance of benefits includes proposals for independent private investment via individual accounts. The author investigates

  11. Feasibility study for positron emission mammography.

    PubMed

    Thompson, C J; Murthy, K; Weinberg, I N; Mako, F

    1994-04-01

    A feasibility study is presented for a small, low-cost, dedicated device for positron emission mammography. Two detector arrays above and below the breast would be placed in a conventional mammography unit. These detectors are sensitive to positron annihilation radiation, and are connected to a coincidence circuit and a multiplane image memory. Images of the distribution of positron-emitting isotope are obtained in real time by incrementing the memory location at the intersection of each line of response. Monte Carlo simulations of a breast phantom are compared with actual scans of this phantom in a conventional PET scanner. The simulations and experimental data are used to predict the performance of the proposed system. Spatial resolution experiments using very narrow bismuth germanate BGO crystals suggest that spatial resolutions of about 2 mm should be possible. The efficiency of the proposed device is about ten times that of a conventional brain scanner. The scatter fraction is greater, but the scattered radiation has a very flat distribution. By designing the device to fit in an existing mammography unit, conventional mammograms can be taken after the injection of the radio-pharmaceutical allowing exact registration of the emission and conventional mammographic images.

  12. Imaging patterns and focal lesions in fatty liver: a pictorial review.

    PubMed

    Venkatesh, Sudhakar K; Hennedige, Tiffany; Johnson, Geoffrey B; Hough, David M; Fletcher, Joel G

    2016-12-20

    Non-alcoholic fatty liver disease is the most common cause of chronic liver disease and affects nearly one-third of US population. With the increasing trend of obesity in the population, associated fatty change in the liver will be a common feature observed in imaging studies. Fatty liver causes changes in liver parenchyma appearance on imaging modalities including ultrasound, computed tomography (CT), and magnetic resonance imaging (MRI) and may affect the imaging characteristics of focal liver lesions (FLLs). The imaging characteristics of FLLs were classically described in a non-fatty liver. In addition, focal fatty change and focal fat sparing may also simulate FLLs. Knowledge of characteristic patterns of fatty change in the liver (diffuse, geographical, focal, subcapsular, and perivascular) and their impact on the detection and characterization of FLL is therefore important. In general, fatty change may improve detection of FLLs on MRI using fat suppression sequences, but may reduce sensitivity on a single-phase (portal venous) CT and conventional ultrasound. In patients with fatty liver, MRI is generally superior to ultrasound and CT for detection and characterization of FLL. In this pictorial essay, we describe the imaging patterns of fatty change in the liver and its effect on detection and characterization of FLLs on ultrasound, CT, MRI, and PET.

  13. Screening Mammography Utilization in Tennessee Women: The Association with Residence

    ERIC Educational Resources Information Center

    Brown, Kathleen C.; Fitzhugh, Eugene C.; Neutens, James J.; Klein, Diane A.

    2009-01-01

    Context: Approximately 70% of US women over age 40 report mammography screening within 2 years. However, rates are likely to vary by age, income, educational level, and residence. Purpose: To describe the prevalence of screening mammography and associated factors in women living in rural and urban areas of Tennessee. Methods: Using pooled data…

  14. Reproducibility of Mammography Units, Film Processing and Quality Imaging

    NASA Astrophysics Data System (ADS)

    Gaona, Enrique

    2003-09-01

    The purpose of this study was to carry out an exploratory survey of the problems of quality control in mammography and processors units as a diagnosis of the current situation of mammography facilities. Measurements of reproducibility, optical density, optical difference and gamma index are included. Breast cancer is the most frequently diagnosed cancer and is the second leading cause of cancer death among women in the Mexican Republic. Mammography is a radiographic examination specially designed for detecting breast pathology. We found that the problems of reproducibility of AEC are smaller than the problems of processors units because almost all processors fall outside of the acceptable variation limits and they can affect the mammography quality image and the dose to breast. Only four mammography units agree with the minimum score established by ACR and FDA for the phantom image.

  15. Adaptive Computer-Assisted Mammography Training for Improved Breast Cancer Screening

    DTIC Science & Technology

    2012-10-01

    11-1-0755 TITLE: Adaptive Computer-Assisted Mammography Training for Improved Breast Cancer Screening PRINCIPAL INVESTIGATOR: Maciej...AND SUBTITLE 5a. CONTRACT NUMBER Adaptive Computer-Assisted Mammography Training for Improved Breast Cancer Screening 5b. GRANT...propose to research the methodology for constructing adaptive computer-aided education systems for mammography . Improved mammography education could

  16. Mammography Screening – as of 2013

    PubMed Central

    Heywang-Koebrunner, S.; Bock, K.; Heindel, W.; Hecht, G.; Regitz-Jedermann, L.; Hacker, A.; Kaeaeb-Sanyal, V.

    2013-01-01

    Introduction: Since 2008 the German Mammography Screening Programme has been available throughout Germany to all women aged between 50 and 69. The programme strictly follows the European Guidelines. There are controversial discussions in the media as well as in the specialised press. Materials and Methods: Overview of the available data with regard to an evaluation of randomised studies and with regard to quality-assured screening programmes in accordance with EU Guidelines (including data from 18 screening countries). Results: Positive effects of screening: reduction in mortality, less invasive treatment. Negative effects: False-positive diagnoses and biopsy recommendations, so-called overdiagnoses, radiation dose. Limits of screening: Interval carcinomas, incomplete reduction in mortality. A mathematical synopsis of the latest publications from the European screening programmes with the diagnosis rates in Germany determined from > 4.6 million screening examinations produces the following: a total of 10 000 mammograms are created for 1000 women (P) taking part in the Mammography Screening Programme (each of whom undergoes 10 mammograms in 20 years). Overall, the risk of triggering breast cancer through a mammogram is very clearly below the annual natural risk of suffering from breast cancer. In the German screening, of these 1000 women, an average of 288 women are called back once in 20 years as a result of changes that are ultimately benign (< 3 % per cycle). Of these, 74 of the 288 women undergo a biopsy due to a benign change (false-positive biopsy recommendations, usually punch or vacuum biopsies). According to EUROSCREEN, 71 carcinomas develop among participants (56 are discovered in the screening, 15 in the interval), and 67 carcinomas among non-participants (N-P) (in some cases, several years later) during this period. The 4 additional diagnoses among the Ps are referred to as overdiagnoses, as they do not contribute to a reduction in mortality

  17. Emotions in context: pictorial influences on affective attributions.

    PubMed

    Marian, Diane E; Shimamura, Arthur P

    2012-04-01

    The visual illusion Terror Subterra, by Roger Shepard (1990), depicts a seemingly large creature chasing another in a tunnel, yet both creatures are physically identical. In addition to this visual illusion, the two creatures also appear to exhibit different emotions, as the background creature (the pursuer) appears angry whereas the foreground creature (the pursued) appears fearful. We explored this context effect by first establishing the magnitude of the emotional bias effect. We then modified the original drawing in various ways, such as equating for perceived size, removing one creature from the scene, and removing the pictorial context altogether. Findings suggest that the emotional bias is due to the pictorial setting and to the perceived social-emotional relationship between the two creatures. These results highlight the importance of both perceptual and social-emotional influences in driving affective attributions.

  18. SOFT CORONAL X-RAYS FROM {beta} PICTORIS

    SciTech Connect

    Guenther, H. M.; Wolk, S. J.; Drake, J. J.; Lisse, C. M.; Robrade, J.; Schmitt, J. H. M. M.

    2012-05-01

    A-type stars are expected to be X-ray dark, yet weak emission has been detected from several objects in this class. We present new Chandra/HRC-I observations of the A5 V star {beta} Pictoris. It is clearly detected with a flux of (9 {+-} 2) Multiplication-Sign 10{sup -4} counts s{sup -1}. In comparison with previous data this constrains the emission mechanism and we find that the most likely explanation is an optically thin, collisionally dominated, thermal emission component with a temperature around 1.1 MK. We interpret this component as a very cool and dim corona, with log L{sub X} /L{sub bol} = -8.2 (0.2-2.0 keV). Thus, it seems that {beta} Pictoris shares more characteristics with cool stars than previously thought.

  19. Three Essays on College Quality

    ERIC Educational Resources Information Center

    Seki, Mai

    2012-01-01

    This dissertation consists of three essays on adolescents' post secondary education choices and labor market returns. The first chapter analyzes returns to selectivity of four-year colleges by different post-bachelor's degree schooling paths. The second chapter documents the role of family income in college application and enrollment…

  20. Essays on Art and Education.

    ERIC Educational Resources Information Center

    Geering, Adrian D.

    This document contains 10 essays which focus on various aspects of art education in the elementary, secondary, and postsecondary educational institutions of Australia. Titles are "Art Education in Australia," The Visual Arts and Society,""The Parallels Between Primitive Art and Child Art,""The Mildura Sculpture…

  1. Two Essays in Economic Education

    ERIC Educational Resources Information Center

    Evans, Brent A.

    2013-01-01

    Prior researchers (Anderson et al. 1994; Ballard & Johnson 2004; Hoag & Benedict 2010) have shown that different math abilities do not equally correlate with success in economics, yet no research has specifically compared algebra and geometry skills as predictors of economics success. In the first essay, I find that students' standardized…

  2. Women's Studies: A Bibliographic Essay.

    ERIC Educational Resources Information Center

    Kirtland, Monika

    The essay section provides a definition and short history of women's studies and explores the implications in regard to the administration and teaching of such courses. The bibliography lists and annotates material useful for all levels of education. Information sources covered include government agencies and societies, reference sources (such as…

  3. Essays in Economics of Education

    ERIC Educational Resources Information Center

    Romano, Teresa Foy

    2014-01-01

    This dissertation consists of three separate essays on the economics of education. In the first chapter, co-authored with Esteban Aucejo, studies the relative effectiveness of reducing absences to extending the school calendar on test score performance. Using administrative data for North Carolina public schools, we exploit a state policy that…

  4. Essays in Education and Macroeconomics

    ERIC Educational Resources Information Center

    Herrington, Christopher M.

    2013-01-01

    This dissertation consists of three essays on education and macroeconomics. The first chapter analyzes whether public education financing systems can account for large differences among developed countries in earnings inequality and intergenerational earnings persistence. I first document facts about public education in the U.S. and Norway, which…

  5. Halley's Comet: A Bibliographic Essay.

    ERIC Educational Resources Information Center

    Gallant, Stephen L.

    1985-01-01

    This bibliographic essay evaluates six books on Halley's Comet as science writings that fall into three categories: middle school and junior high-level books; senior high to adult-level books; and advanced level. Author, number of pages, publication date, price, International Standard Book Number, and publisher information are provided. (EJS)

  6. Sequential Effects in Essay Ratings

    ERIC Educational Resources Information Center

    Attali, Yigal

    2011-01-01

    Contrary to previous research on sequential ratings of student performance, this study found that professional essay raters of a large-scale standardized testing program produced ratings that were drawn toward previous ratings, creating an assimilation effect. Longer intervals between the two adjacent ratings and higher degree of agreement with…

  7. Adaptive Computer-Assisted Mammography Training for Improved Breast Cancer Screening

    DTIC Science & Technology

    2014-10-01

    education could lead to improved benefit of mammography to breast cancer care and in turn to decreased mortality from the disease. The project...models. The proposed adaptive system could improve education in mammography. This may in turn result in improved benefit of mammography in breast cancer ...adaptive system could improve education in mammography. This may in turn result in improved benefit of mammography in breast cancer detection and lower

  8. New motion illusion caused by pictorial motion lines.

    PubMed

    Kawabe, Takahiro; Miura, Kayo

    2008-01-01

    Motion lines (MLs) are a pictorial technique used to represent object movement in a still picture. This study explored how MLs contribute to motion perception. In Experiment 1, we reported the creation of a motion illusion caused by MLs: random displacements of objects with MLs on each frame were perceived as unidirectional global motion along the pictorial motion direction implied by MLs. In Experiment 2, we showed that the illusory global motion in the peripheral visual field captured the perceived motion direction of random displacement of objects without MLs in the central visual field, and confirmed that the results in Experiment 1 did not stem simply from response bias, but resulted from perceptual processing. In Experiment 3, we showed that the spatial arrangement of orientation information rather than ML length is important for the illusory global motion. Our results indicate that the ML effect is based on perceptual processing rather than response bias, and that comparison of neighboring orientation components may underlie the determination of pictorial motion direction with MLs.

  9. Measuring 3D point configurations in pictorial space

    PubMed Central

    Wagemans, Johan; van Doorn, Andrea J; Koenderink, Jan J

    2011-01-01

    We propose a novel method to probe the depth structure of the pictorial space evoked by paintings. The method involves an exocentric pointing paradigm that allows one to find the slope of the geodesic connection between any pair of points in pictorial space. Since the locations of the points in the picture plane are known, this immediately yields the depth difference between the points. A set of depth differences between all pairs of points from an N-point (N > 2) configuration then yields the configuration in depth up to an arbitrary depth offset. Since an N-point configuration implies N(N−1) (ordered) pairs, the number of observations typically far exceeds the number of inferred depths. This yields a powerful check on the geometrical consistency of the results. We report that the remaining inconsistencies are fully accounted for by the spread encountered in repeated observations. This implies that the concept of ‘pictorial space’ indeed has an empirical significance. The method is analyzed and empirically verified in considerable detail. We report large quantitative interobserver differences, though the results of all observers agree modulo a certain affine transformation that describes the basic cue ambiguities. This is expected on the basis of a formal analysis of monocular optical structure. The method will prove useful in a variety of potential applications. PMID:23145227

  10. Digital mammography: physical principles and future applications.

    PubMed

    Gambaccini, Mauro; Baldelli, Paola

    2003-01-01

    Mammography is currently considered the best tool for the detection of breast cancer, pathology with a rate of incidence in constant increase. To produce the radiological picture a screen film combination is conventionally used. One of the inherent limitations of screen- film combination is the fact that the detection, display and storage processes are one and the same, making it impossible to separately optimize each stage. These limitations can be overcome with digital systems. In this work we evaluate the main characteristics of digital detectors available on the market and we compare the performance of digital and conventional systems. Digital mammography, due to the possibility to process images, offers many potential advantages, among these the possibility to introduce the dual-energy technique which employs the composition of two digital images obtained with two different energies to enhance the inherent contrast of pathologies by removing the uniform background. This technique was previously tested by using synchrotron monochromatic beam and a digital detector, and then the Senographe 2000D full-field digital system manufactured by GE Medical Systems. In this work we present preliminary results and the future applications of this technique.

  11. Preliminary experience with monoenergetic photon mammography

    SciTech Connect

    Johnston, R.E.; Washburn, D.; Pisano, E.; Thomlinson, W.C.; Chapman, D.; Gmur, N.F.; Zhong, Zhong; Sayers, D.

    1995-12-31

    We are using a beam port at the National Synchrotron Light Source facility at Brookhaven National Laboratory as a source of monoenergetic photons. The photon source is radiation from a bending magnet on the X-ray storage ring and provides a usable X-ray spectrum from 5 keV to over 50 keV. A tunable crystal monochromotor is used for energy selection. The beam is 79mm wide and 0.5 mm high. We imaged the ACR mammography phantom and a contrast-detail phantom using a phosphor plate as the unaging detector. Phantom images were obtained at 16, 18, 20 and 22 keV. Phantom thickness varied from 15 mm to 82 mm. These images were compared to images obtained with a conventional dedicated mammography unit. Subjective preliminary results show that image contrast of the monoenergetic images is similar to those obtained from the conventional x-ray source with somewhat sharper and cleaner images from the monoenergetic source. Quantitative analysis shows that the monoenergetic images have improved contrast compared to the polyenergetic derived images. Entrance skin dose measurements show a factor of 5 to 10 times less radiation for the monoenergetic images with equivalent or better contrast Although there remain a number of technical problems to be addressed and much more work to be done, we are encouraged to further explore the use of monoenergetic imaging.

  12. Mammography screening among the elderly: A research challenge

    PubMed Central

    Sanderson, Maureen; Levine, Robert S.; Fadden, Mary K.; Kilbourne, Barbara; Pisu, Maria; Cain, Van; Husaini, Baqar A.; Langston, Michael; Gittner, Lisa; Zoorob, Roger; Rust, George S.; Hennekens, Charles H.

    2015-01-01

    Background Randomized trials demonstrate clear benefits of mammography screening in women through age 74 years. We explored age- and race-specific rates of mammography screening and breast cancer mortality among women ages 69 to 84 years. Methods We analyzed Medicare claims data for women residing within Surveillance, Epidemiology and End Results (SEER) geographic areas from 1995 to 2009 from 64,384 non-Hispanic women (4,886 black and 59,498 white) and ascertained all primary breast cancer cases diagnosed between ages 69 and 84 years. The exposure was annual or biennial screening mammography during the four years immediately preceding diagnosis. The outcome was breast cancer mortality during the ten years immediately following diagnosis. Results After adjustment for stage at diagnosis, radiation therapy, chemotherapy, co-morbid conditions and contextual socio-economic status, hazard ratios (HR’s) (and 95% confidence intervals) for breast cancer mortality relative to no/irregular mammography at 10 years for women ages 69–84 years at diagnosis were 0.31 (0.29–0.33) for annual and 0.47 (0.44–0.51) for biennial mammography among whites and 0.36 (0.29–0.44) for annual and 0.47 (0.37–0.58) for biennial mammography among blacks. Trends were similar at five years overall as well as stratified by ages 69–74, 75–78, and 79–84. Conclusions In these Medicare claims and SEER data, elderly non-Hispanic women who self-selected for annual mammography had lower ten-year breast cancer mortality than corresponding women who self-selected for either biennial or no/irregular mammography. These findings were similar among black and white women. The data highlight the evidentiary limitations of data used for current screening mammography recommendations. PMID:26169884

  13. Clinical Optimization of Current Digital Mammography Systems (Breast Cancer)

    DTIC Science & Technology

    1994-01-20

    AD-A280 249 ’ •) AD_______ GRANT NO: DAMD17-93-J-3008 TITLE: CLINICAL OPTIMIZATION OF CURRENT DIGITAL MAMMOGRAPHY SYSTEMS (BREAST CANCER ) PRINCIPAL...Current Digital Mammography Systems (Breast Cancer ) Grant No. 6 . _ _ _ _ _ _ __ D A M D 1 7 - 9 3 - J - 3 0 0 8 AUTH•OR(S) Matthew T. Freedman, M.D...will be continuing our research with a 42 micron film digitizer when a machine arrives at our site early in 1994. Breast Cancer , Mammography, Digital

  14. An assessment of American Indian women's mammography experiences

    PubMed Central

    2010-01-01

    Background Mortality from breast cancer has increased among American Indian/Alaskan Native (AI/AN) women. Despite this alarming reality, AI/AN women have some of the lowest breast cancer screening rates. Only 37% of eligible AI/AN women report a mammogram within the last year and 52% report a mammogram within the last two years compared to 57% and 72% for White women. The experiences and satisfaction surrounding mammography for AI/AN women likely are different from that of women of other racial/ethnic groups, due to cultural differences and limited access to Indian Health Service sponsored mammography units. The overall goals of this study are to identify and understand the mammography experiences and experiential elements that relate to satisfaction or dissatisfaction with mammography services in an AI/AN population and to develop a culturally-tailored AI/AN mammography satisfaction survey. Methods and Design The three project aims that will be used to guide this work are: 1) To compare the mammography experiences and satisfaction with mammography services of Native American/Alaska Native women with that of Non-Hispanic White, Hispanic, and Black women, 2) To develop and validate the psychometric properties of an American Indian Mammography Survey, and 3) To assess variation among AI/AN women's assessments of their mammography experiences and mammography service satisfaction. Evaluations of racial/ethnic differences in mammography patient satisfaction have received little study, particularly among AI/AN women. As such, qualitative study is uniquely suited for an initial examination of their experiences because it will allow for a rich and in-depth identification and exploration of satisfaction elements. Discussion This formative research is an essential step in the development of a validated and culturally tailored AI/AN mammography satisfaction assessment. Results from this project will provide a springboard from which a maximally effective breast cancer

  15. CR mammography: Design and implementation of a quality control program

    SciTech Connect

    Moreno-Ramirez, A.; Brandan, M. E.; Villasenor-Navarro, Y.; Galvan, H. A.; Ruiz-Trejo, C.

    2012-10-23

    Despite the recent acquisition of significant quantities of computed radiography CR equipment for mammography, Mexican regulations do not specify the performance requirements for digital systems such as those of CR type. The design of a quality control program QCP specific for CR mammography systems was thus considered relevant. International protocols were taken as reference to define tests, procedures and acceptance criteria. The designed QCP was applied in three CR mammography facilities. Important deficiencies in spatial resolution, noise, image receptor homogeneity, artifacts and breast thickness compensation were detected.

  16. CR mammography: Design and implementation of a quality control program

    NASA Astrophysics Data System (ADS)

    Moreno-Ramírez, A.; Brandan, M. E.; Villaseñor-Navarro, Y.; Galván, H. A.; Ruiz-Trejo, C.

    2012-10-01

    Despite the recent acquisition of significant quantities of computed radiography CR equipment for mammography, Mexican regulations do not specify the performance requirements for digital systems such as those of CR type. The design of a quality control program QCP specific for CR mammography systems was thus considered relevant. International protocols were taken as reference to define tests, procedures and acceptance criteria. The designed QCP was applied in three CR mammography facilities. Important deficiencies in spatial resolution, noise, image receptor homogeneity, artifacts and breast thickness compensation were detected.

  17. A Reflective Essaying Model for Higher Education

    ERIC Educational Resources Information Center

    Badley, Graham

    2009-01-01

    Purpose: The purpose of this paper is to outline a reflective essaying model as a useful way of encouraging learning in higher education. It aims to define reflective essaying as the free and serious play of mind on an interesting topic in an attempt to learn. Design/methodology/approach: Reflective essaying is first introduced as a unifying…

  18. Enriching Automated Essay Scoring Using Discourse Marking.

    ERIC Educational Resources Information Center

    Burstein, Jill; Kukich, Karen; Wolff, Susanne; Lu, Chi; Chodorow, Martin

    Electronic Essay Rater (e-rater) is a prototype automated essay scoring system built at Educational Testing Service that uses discourse marking in addition to syntactic information and topical content vector analyses to assign essay scores automatically. This paper gives a general description of e-rater as a whole, but its emphasis is on the…

  19. In Defense of the Formula Essay

    ERIC Educational Resources Information Center

    Haluska, Jan Charles

    2007-01-01

    In 1970, the author learned a simple step in making essays from his advisor. His advisor used a drawing of the Parthenon to illustrate the creation of a five-paragraph essay. It was obvious that his advisor was hesitant on teaching them a very simple concept of essay writing because it was pretty mechanical. Like his advisor, a lot of teachers…

  20. Essays on Dynamic Competition and Academic Entrepreneurship

    ERIC Educational Resources Information Center

    Pham, Huyen T.

    2012-01-01

    My dissertation focuses on dynamic firm competition and academic entrepreneurship. The first essay studies the dynamics and equilibrium outcomes of a duopoly in which firms make decisions about both capacity expansion and cost reduction. The second essay is an extension of the framework used in the first essay to study the strategic roles of…

  1. Essay Assessment with Latent Semantic Analysis

    ERIC Educational Resources Information Center

    Miller, Tristan

    2003-01-01

    Latent semantic analysis (LSA) is an automated, statistical technique for comparing the semantic similarity of words or documents. In this article, I examine the application of LSA to automated essay scoring. I compare LSA methods to earlier statistical methods for assessing essay quality, and critically review contemporary essay-scoring systems…

  2. Going Further: Essays in Further Education.

    ERIC Educational Resources Information Center

    Flint, Colin, Ed.; Austin, Michael, Ed.

    This volume contains 16 essays on Further Education (FE) in the context of its changing status and role in the educational and economic life of Great Britain. The essays are grouped around four main themes: (1) FE and mission; (2) managerial responsibilities; (3) context; and (4) diversity. The essays are: "FE Makes Itself Indispensable"…

  3. Restructuring for Urban Student Success: Essay Collection.

    ERIC Educational Resources Information Center

    Jackson, Barbara, Ed.; Levine, Jodi, Ed.; Patton, Judy, Ed.

    This publication presents essays by members of Restructuring for Urban Student Success (RUSS) and other faculty, administrators, staff, and graduate students on participating campuses. The essays describe the work of RUSS and document curricular restructuring and reform efforts occurring at RUSS partner institutions. Part 1 includes essays by RUSS…

  4. The Color of Leadership. Essays

    ERIC Educational Resources Information Center

    Jansen, Jonathan D.

    2005-01-01

    On July 1, 2000, the author became the first black dean of Education in the almost 100 year existence of the formidable University of Pretoria, South Africa. This essay offers a set of meditations on being a black dean in a white university at the birth of a post-apartheid democracy. There are many sides to this narrative. It is a story of leading…

  5. Determinants of the number of mammography units in 31 countries with significant mammography screening

    PubMed Central

    Autier, P; Ouakrim, D A

    2008-01-01

    In the 2000s, most of the female population of industrialised countries had access to mammography breast cancer screening, but with variable modalities among the countries. We assessed the number of mammography units (MUs) in 31 European, North American and Asian countries where significant mammography activity has existed for over 10 years, collecting data on the number of such units and of radiologists by contacting institutions in each country likely to provide the relevant information. Around 2004, there were 32 324 MU in 31 countries, the number per million women ranging from less than 25 in Turkey, Denmark, the Netherlands, the United Kingdom, Norway, Poland and Hungary to more than 80 in Cyprus, Italy, France, the United States and Austria. In a multivariate analysis, the number of MUs was positively associated with the number of radiologists (P=0.0081), the number of women (P=0.0023) and somewhat with the country surface area (P=0.077). There is considerable variation in the density of MU across countries and the number of MUs in service are often well above what would be necessary according to local screening recommendations. High number of MUs in some countries may have undesirable consequences, such as unnecessarily high screening frequency and decreased age at which screening is started. PMID:18781176

  6. A proposal for a national mammography database: content, purpose, and value.

    PubMed

    Osuch, J R; Anthony, M; Bassett, L W; DeBor, M; D'Orsi, C; Hendrick, R E; Linver, M; Smith, R

    1995-06-01

    A national mammography database is a centralized, computerized method of data collection consisting of two possible parts: a national mammography audit and a system for monitoring and tracking patients. A national mammography audit refers to collecting and analyzing medical audit data of individual mammography practices at a national level and is a critical step in improving the interpretive component of mammography. The monitoring and tracking component refers to a centralized system that provides women and physicians with a recruitment and follow-up mechanism to optimize participation in mammography services. Both parts of a national mammography database represent important components in the improvement of mammography quality. However, unique scientific, legal, and fiscal concerns are important to consider before establishing a national mammography database.

  7. Influence of advertisement on women's attitudes toward mammography screening.

    PubMed

    Collins, C; Davis, L S; Rentz, K; Vannoy, D

    1997-01-01

    This project represents an effort to incorporate a feminist perspective into research on mammography screening. The purpose of this study was to assess women's attitudes toward four advertisements designed to encourage mammography screening. The goal was to create awareness about women's attitudes toward mammography advertisements in order to encourage the development of more effective and responsive motivational materials. The results indicated that each ad communicated different messages about the seriousness of breast cancer and the efficacy of mammography in detecting early breast cancer. Each ad also affected women differently regarding their feelings of control over breast cancer, their perceived loss of sex appeal resulting from a breast cancer diagnosis, and their general fear of breast cancer.

  8. Digital mammography, cancer screening: Factors important for image compression

    NASA Technical Reports Server (NTRS)

    Clarke, Laurence P.; Blaine, G. James; Doi, Kunio; Yaffe, Martin J.; Shtern, Faina; Brown, G. Stephen; Winfield, Daniel L.; Kallergi, Maria

    1993-01-01

    The use of digital mammography for breast cancer screening poses several novel problems such as development of digital sensors, computer assisted diagnosis (CAD) methods for image noise suppression, enhancement, and pattern recognition, compression algorithms for image storage, transmission, and remote diagnosis. X-ray digital mammography using novel direct digital detection schemes or film digitizers results in large data sets and, therefore, image compression methods will play a significant role in the image processing and analysis by CAD techniques. In view of the extensive compression required, the relative merit of 'virtually lossless' versus lossy methods should be determined. A brief overview is presented here of the developments of digital sensors, CAD, and compression methods currently proposed and tested for mammography. The objective of the NCI/NASA Working Group on Digital Mammography is to stimulate the interest of the image processing and compression scientific community for this medical application and identify possible dual use technologies within the NASA centers.

  9. Elasto-mammography: Theory, Algorithm, and Phantom Study

    PubMed Central

    Liu, Y.; Sun, L. Z.; Wang, G.; Fajardo, L. L.

    2006-01-01

    A new imaging modality framework, called elasto-mammography, is proposed to generate the elastograms of breast tissues based on conventional X-ray mammography. The displacement information is extracted from mammography projections before and after breast compression. Incorporating the displacement measurement, an elastography reconstruction algorithm is specifically developed to estimate the elastic moduli of heterogeneous breast tissues. Case studies with numerical breast phantoms are conducted to demonstrate the capability of the proposed elasto-mammography. Effects of noise with measurement, geometric mismatch, and elastic contrast ratio are evaluated in the numerical simulations. It is shown that the proposed methodology is stable and robust for characterization of the elastic moduli of breast tissues from the projective displacement measurement. PMID:23165036

  10. A Novel Method to Assess Incompleteness of Mammography Reports

    PubMed Central

    Gimenez, Francisco J.; Wu, Yirong; Burnside, Elizabeth S.; Rubin, Daniel L.

    2014-01-01

    Mammography has been shown to improve outcomes of women with breast cancer, but it is subject to inter-reader variability. One well-documented source of such variability is in the content of mammography reports. The mammography report is of crucial importance, since it documents the radiologist’s imaging observations, interpretation of those observations in terms of likelihood of malignancy, and suggested patient management. In this paper, we define an incompleteness score to measure how incomplete the information content is in the mammography report and provide an algorithm to calculate this metric. We then show that the incompleteness score can be used to predict errors in interpretation. This method has 82.6% accuracy at predicting errors in interpretation and can possibly reduce total diagnostic errors by up to 21.7%. Such a method can easily be modified to suit other domains that depend on quality reporting. PMID:25954448

  11. A novel method to assess incompleteness of mammography reports.

    PubMed

    Gimenez, Francisco J; Wu, Yirong; Burnside, Elizabeth S; Rubin, Daniel L

    2014-01-01

    Mammography has been shown to improve outcomes of women with breast cancer, but it is subject to inter-reader variability. One well-documented source of such variability is in the content of mammography reports. The mammography report is of crucial importance, since it documents the radiologist's imaging observations, interpretation of those observations in terms of likelihood of malignancy, and suggested patient management. In this paper, we define an incompleteness score to measure how incomplete the information content is in the mammography report and provide an algorithm to calculate this metric. We then show that the incompleteness score can be used to predict errors in interpretation. This method has 82.6% accuracy at predicting errors in interpretation and can possibly reduce total diagnostic errors by up to 21.7%. Such a method can easily be modified to suit other domains that depend on quality reporting.

  12. The Use of Error Data to Study the Development of Verbal Encoding of Pictorial Stimuli.

    ERIC Educational Resources Information Center

    Cramer, Phebe

    If older children automatically label pictorial stimuli, then their performance should be impaired on tasks in which such labeling would increase the error rate. Children were asked to learn pairs of verbal or pictorial stimuli which, when combined, formed a different compound word (BUTTER-FLY). Subsequently, a false recognition test that included…

  13. Pre-Hispanic Pictorial Communication: The Codex System of the Mixtec of Oaxaca, Mexico.

    ERIC Educational Resources Information Center

    Troike, Nancy P.

    1990-01-01

    Summarizes the nature of the pre-Hispanic pictorial communication system used by the Mixtec people of Mexico, who were creating manuscripts in which they recorded their histories, genealogies, and religious beliefs long before the Spanish reached the New World. Explains and illustrates the principal pictorial conventions. (PRA)

  14. A Systematic Characterization of Cognitive Techniques for Learning from Textual and Pictorial Representations

    ERIC Educational Resources Information Center

    Ploetzner, Rolf; Lowe, Richard; Schlag, Sabine

    2013-01-01

    Pictorial representations can play a pivotal role in both printed and digital learning material. Although there has been extensive research on cognitive techniques and strategies for learning from text, the same cannot be said for static and dynamic pictorial representations. In this paper we propose a systematic characterization of cognitive…

  15. Assessing the Efficacy of Pictorial Preference Assessments for Children with Developmental Disabilities

    ERIC Educational Resources Information Center

    Heinicke, Megan R.; Carr, James E.; Pence, Sacha T.; Zias, Danika R.; Valentino, Amber L.; Falligant, John M.

    2016-01-01

    Past research has demonstrated that pictorial preference assessments can predict subsequent reinforcement effects for individuals with developmental disabilities only when access to the selected stimulus is provided contingent on a pictorial selection. The purpose of the present investigation was to assess more comprehensively the feasibility of…

  16. Dual-energy contrast-enhanced spectral mammography (CESM).

    PubMed

    Daniaux, Martin; De Zordo, Tobias; Santner, Wolfram; Amort, Birgit; Koppelstätter, Florian; Jaschke, Werner; Dromain, Clarisse; Oberaigner, Willi; Hubalek, Michael; Marth, Christian

    2015-10-01

    Dual-energy contrast-enhanced mammography is one of the latest developments in breast care. Imaging with contrast agents in breast cancer was already known from previous magnetic resonance imaging and computed tomography studies. However, high costs, limited availability-or high radiation dose-led to the development of contrast-enhanced spectral mammography (CESM). We reviewed the current literature, present our experience, discuss the advantages and drawbacks of CESM and look at the future of this innovative technique.

  17. Ultrasound in obstructive lung diseases: the effect of airway obstruction on diaphragm kinetics. A short pictorial essay.

    PubMed

    Zanforlin, Alessandro; Smargiassi, Andrea; Inchingolo, Riccardo; Valente, Salvatore; Ramazzina, Emilio

    2015-12-01

    The ultrasound study of the chest is showing a continuous development. This technique could be helpful in managing several chest diseases, but it is limited to the acoustic windows provided by intercostal spaces and by the inability to study healthy lung parenchyma and all intra-parenchymal diseases such as chronic obstructive lung disease (COPD), because the interaction between ventilated lung and ultrasound generates only artifacts. Currently, there are few applications of ultrasound that are useful in COPD, with recent studies providing some innovation potentially useful in clinical practice. The similarity of the trend between the time/volume curve of spirometry and the M-mode representation of diaphragm during forced breath allowed to identify the M-mode Index of Obstruction (MIO), an index obtained from the ratio between forced diaphragmatic excursion in the first second (FEDE1, cm) and the maximal expiratory diaphragmatic excursion (EDEMax, cm). MIO has shown a linear correlation with the ratio between forced expiratory volume in the first second (FEV1) and vital capacity (VC), used in spirometry to identify airways obstruction. The value of MIO seems to be lower in patients affected by airways obstruction as showed by a recent study. The technique is easy to learn and fast to perform and the analysis could be provided with any ultrasound machine equipped with M-mode. In conclusion, these findings, if confirmed by other studies, could suggest a new add-on screening tool for obstructive lung diseases, in particular COPD, that could be performed during a routine abdominal ultrasound exam.

  18. Formation of ghost images due to metal objects on the surface of the patient's face: A pictorial essay

    PubMed Central

    Ramos, Bárbara Couto; da Silva Izar, Bruna Raquel; Pereira, Jéssica Lourdes Costa; Souza, Priscilla Sena; Valerio, Claudia Scigliano; Tuji, Fabrício Mesquita

    2016-01-01

    Panoramic radiographs are a relatively simple technique that is commonly used in all dental specialties. In panoramic radiographs, in addition to the formation of real images of metal objects, ghost images may also form, and these ghost images can hinder an accurate diagnosis and interfere with the accuracy of radiology reports. Dentists must understand the formation of these images in order to avoid making incorrect radiographic diagnoses. Therefore, the present study sought to present a study of the formation of panoramic radiograph ghost images caused by metal objects in the head and neck region of a dry skull, as well as to report a clinical case n order to warn dentists about ghost images and to raise awareness thereof. An understanding of the principles of the formation of ghost images in panoramic radiographs helps prevent incorrect diagnoses. PMID:27051642

  19. Formation of ghost images due to metal objects on the surface of the patient's face: A pictorial essay.

    PubMed

    Ramos, Bárbara Couto; da Silva Izar, Bruna Raquel; Pereira, Jéssica Lourdes Costa; Souza, Priscilla Sena; Valerio, Claudia Scigliano; Tuji, Fabrício Mesquita; Manzi, Flávio Ricardo

    2016-03-01

    Panoramic radiographs are a relatively simple technique that is commonly used in all dental specialties. In panoramic radiographs, in addition to the formation of real images of metal objects, ghost images may also form, and these ghost images can hinder an accurate diagnosis and interfere with the accuracy of radiology reports. Dentists must understand the formation of these images in order to avoid making incorrect radiographic diagnoses. Therefore, the present study sought to present a study of the formation of panoramic radiograph ghost images caused by metal objects in the head and neck region of a dry skull, as well as to report a clinical case n order to warn dentists about ghost images and to raise awareness thereof. An understanding of the principles of the formation of ghost images in panoramic radiographs helps prevent incorrect diagnoses.

  20. Anatomy of the inferior extensor retinaculum and its role in lateral ankle ligament reconstruction: a pictorial essay.

    PubMed

    Dalmau-Pastor, M; Yasui, Y; Calder, J D; Karlsson, J; Kerkhoffs, G M M J; Kennedy, J G

    2016-04-01

    The inferior extensor retinaculum (IER) is an aponeurotic structure, which is in continuation with the anterior part of the sural fascia. The IER has often been used to augment the reconstruction of the lateral ankle ligaments, for instance in the Broström-Gould procedure, with good outcomes reported. However, its anatomy has not been described in detail and only a few studies are available on this structure. The presence of a non-constant oblique supero-lateral band appears to be important. This structure defines whether the augmentation of the lateral ankle ligaments reconstruction is performed using true IER or only the anterior part of the sural fascia. It is concluded that the use of this structure will have an impact on the resulting ankle stability.

  1. Role of B-scan ocular ultrasound as an adjuvant for the clinical assessment of eyeball diseases: a pictorial essay.

    PubMed

    Dessì, Gerardo; Lahuerta, Eduardo Ferrer; Puce, Fabrizio Giorgio; Mendoza, Luis Humberto Ros; Stefanini, Teseo; Rosenberg, Ilan; Del Prato, Alberto; Perinetti, Michela; Villa, Alessandro

    2015-09-01

    We report our experience in B-mode ocular ultrasonography, focusing on its contribution when the clinical examination proves to be difficult, mainly due to the existence of intraocular opacities of the ocular fundus or diagnostic doubts. We revise the ocular ultrasound technique, its indications and contraindications, comparing to the other imaging techniques. In our experience ultrasonography revealed pathological findings which confirmed the clinical suspicion in most of cases or provide additional information. With understanding of the indications for ultrasonography and proper examination technique, one can gather a vast amount of information not possible with clinical examination alone.

  2. X-ray source for mammography

    DOEpatents

    Logan, Clinton M.

    1994-01-01

    An x-ray source utilizing anode material which shifts the output spectrum to higher energy and thereby obtains higher penetrating ability for screening mammography application, than the currently utilized anode material. The currently used anode material (molybdenum) produces an energy x-ray spectrum of 17.5/19.6 keV, which using the anode material of this invention (e.g. silver, rhodium, and tungsten) the x-ray spectrum would be in the 20-35 keV region. Thus, the anode material of this invention provides for imaging of breasts with higher than average x-ray opacity without increase of the radiation dose, and thus reduces the risk of induced breast cancer due to the radiation dose administered for mammograms.

  3. Digital mammography performed with computed radiography technology.

    PubMed

    Jouan, B

    1999-07-01

    Introduced by Fuji Photo Film Japan in the early 1980s, computed radiography (CR) technology has developed considerably since then to become the mature widely installed technology it is today (about 7500 systems worldwide). Various mammographic examinations require high performance results to which CR complies on demand or following some procedures such as geometrical magnification carried out during the examination. The basic CR principles and digital image processing as well as technical improvements are detailed in this study, which also includes a synthesis of the articles on CR mammographic applications referenced in the bibliography, focusing on strong points, limits and current methods of surpassing these limits. New CR technology development perspectives in mammography and computed assisted diagnosis (CAD) algorithms will allow wider use of this method in the near future.

  4. Contrast-Enhanced Digital Mammography and Angiogenesis

    SciTech Connect

    Rosado-Mendez, I.; Palma, B. A.; Villasenor, Y.; Benitez-Bribiesca, L.; Brandan, M. E.

    2007-11-26

    Angiogenesis could be a means for pouring contrast media around tumors. In this work, optimization of radiological parameters for contrast-enhanced subtraction techniques in mammography has been performed. A modification of Lemacks' analytical formalism was implemented to model the X-ray absorption in the breast with contrast medium and detection by a digital image receptor. Preliminary results of signal-to-noise ratio analysis show the advantage of subtracting two images taken at different energies, one prior and one posterior to the injection of contrast medium. Preliminary experimental results using a custom-made phantom have shown good agreement with calculations. A proposal is presented for the clinical application of the optimized technique, which aims at finding correlations between angiogenesis indicators and dynamic variables of contrast medium uptake.

  5. X-ray source for mammography

    DOEpatents

    Logan, C.M.

    1994-12-20

    An x-ray source is described utilizing anode material which shifts the output spectrum to higher energy and thereby obtains higher penetrating ability for screening mammography application, than the currently utilized anode material. The currently used anode material (molybdenum) produces an energy x-ray spectrum of 17.5/19.6 keV, which using the anode material of this invention (e.g. silver, rhodium, and tungsten) the x-ray spectrum would be in the 20-35 keV region. Thus, the anode material of this invention provides for imaging of breasts with higher than average x-ray opacity without increase of the radiation dose, and thus reduces the risk of induced breast cancer due to the radiation dose administered for mammograms. 6 figures.

  6. Instrumentation optimization for positron emission mammography

    SciTech Connect

    Moses, William W.; Qi, Jinyi

    2003-06-05

    The past several years have seen designs for PET cameras optimized to image the breast, commonly known as Positron Emission Mammography or PEM cameras. The guiding principal behind PEM instrumentation is that a camera whose field of view is restricted to a single breast has higher performance and lower cost than a conventional PET camera. The most common geometry is a pair of parallel planes of detector modules, although geometries that encircle the breast have also been proposed. The ability of the detector modules to measure the depth of interaction (DOI) is also a relevant feature. This paper finds that while both the additional solid angle coverage afforded by encircling the breast and the decreased blurring afforded by the DOI measurement improve performance, the ability to measure DOI is more important than the ability to encircle the breast.

  7. Triple-energy contrast enhanced digital mammography

    NASA Astrophysics Data System (ADS)

    Puong, Sylvie; Milioni de Carvalho, Pablo; Muller, Serge

    2010-04-01

    With the injection of iodine, Contrast Enhanced Digital Mammography (CEDM) provides functional information about breast tumour angiogenesis that can potentially help in cancer diagnosis. In order to generate iodine images in which the gray level is proportional to the iodine thickness, temporal and dual-energy approaches have already been considered. The dual-energy method offers the advantage of less patient motion artifacts and better comfort during the exam. However, this approach requires knowledge of the breast thickness at each pixel. Generally, as compression is applied, the breast thickness at each pixel is taken as the compression thickness. Nevertheless, in the breast border region, this assumption is not correct anymore and this causes inaccuracies in the iodine image. Triple-Energy CEDM could overcome these limitations by providing supplemental information in the form of a third image acquired with a different spectrum than the other two. This precludes the need of a priori knowledge of the breast thickness. Moreover, with Triple-Energy CEDM, breast thickness and glandularity maps could potentially be derived. In this study, we first focused on the method to recombine the three images in order to generate the iodine image, analyzing the performance of either quadratic, cubic or conic recombination functions. Then, we studied the optimal acquisition spectra in order to maximize the iodine SDNR in the recombined image for a given target total glandular dose. The concept of Triple-Energy CEDM was validated on simulated textured images and poly-energetic images acquired with a conventional X-ray mammography tube.

  8. CT angiography in the abdomen: a pictorial review and update.

    PubMed

    Liu, Peter S; Platt, Joel F

    2014-02-01

    The development of multidetector CT technology and helical scanning techniques has revolutionized the use of CT for primary diagnostic evaluation of the abdominal vasculature, particularly the arterial system. CT angiography has numerous benefits relative to conventional catheter angiography, and has largely replaced catheter-based techniques in many clinical algorithms. This pictorial review and update will cover important technical principles related to modern CT angiography (including contrast delivery and dose considerations), discuss relevant anatomy and variants, and illustrate numerous arterial conditions related to the abdominal aorta and branch vessels.

  9. MR imaging of cavernous sinus lesions: Pictorial review.

    PubMed

    Nadarajah, Jeyaseelan; Madhusudhan, Kumble Seetharama; Yadav, Ajay Kumar; Chandrashekhara, Sheragaru Hanumanthappa; Kumar, Atin; Gupta, Arun Kumar

    2015-12-01

    The main purpose of this pictorial review is to highlight the important MR imaging findings of various conditions involving the cavernous sinus in addition to brief description of normal anatomy. The pathological conditions that can involve the cavernous sinus can be categorized into infective, inflammatory, granulomatous, vascular and neoplastic causes. Imaging, especially with MRI, plays an important role not only in detection but also in definition of disease extent and in characterization of the pathology. Currently, high-resolution MR images clearly show various components of cavernous sinus which help in making a proper diagnosis and thus appropriate further management.

  10. Farmworker Housing: A Photo Essay.

    PubMed

    Arcury, Thomas A; Summers, Phillip

    2015-11-01

    Migrant and seasonal farmworkers often reside in poor housing conditions which expose them to numerous hazards. These housing conditions are an issue of environmental health and justice. The photographs in this essay illustrate the living conditions confronted by farmworkers, offering a visual context for the reviews published in this issue of New Solutions. Farmworker housing conditions are often shocking to those who have not visited farmworker communities. Continued research is needed to document these conditions, how they affect the health of farmworkers, and provide leverage in the struggle to improve farmworker housing conditions.

  11. Painting cracks: A way to investigate the pictorial matter

    NASA Astrophysics Data System (ADS)

    Giorgiutti-Dauphiné, Frédérique; Pauchard, Ludovic

    2016-08-01

    An old painting generally exhibits a wide variety of crack patterns. From a strictly aesthetic point of view, cracks are undesirable; nevertheless, they can be seen as the fingerprints of the painting and provide valuable knowledge about the art piece. Precisely, the morphology of crack patterns can be related to the mechanical properties of the pictorial matter or they can reveal information about the methods used by the artist or the conditions of conservation. In the present paper, we show how drying dispersions of colloidal particles in a volatile solvent on a non-porous substrate provides a good candidate to study crack formation in a solid layer. We recover the crack patterns observed in paintings, and we investigate the role of the substrate, e.g., the sub-layer, and of the thickness of the layer in the crack spacing. We show how to deduce mechanical properties of a sub-layer, provided the thickness and the elastic modulus of the layer are known. These experiments aim to propose a potentially non-invasive method to deduce quantitative information about mechanical properties of a pictorial matter which could be of great interest for cultural heritage.

  12. Fast spin of the young extrasolar planet β Pictoris b

    NASA Astrophysics Data System (ADS)

    Snellen, Ignas A. G.; Brandl, Bernhard R.; de Kok, Remco J.; Brogi, Matteo; Birkby, Jayne; Schwarz, Henriette

    2014-05-01

    The spin of a planet arises from the accretion of angular momentum during its formation, but the details of this process are still unclear. In the Solar System, the equatorial rotation velocities and, consequently, spin angular momenta of most of the planets increase with planetary mass; the exceptions to this trend are Mercury and Venus, which, since formation, have significantly spun down because of tidal interactions. Here we report near-infrared spectroscopic observations, at a resolving power of 100,000, of the young extrasolar gas giant planet β Pictoris b (refs 7, 8). The absorption signal from carbon monoxide in the planet's thermal spectrum is found to be blueshifted with respect to that from the parent star by approximately 15 kilometres per second, consistent with a circular orbit. The combined line profile exhibits a rotational broadening of about 25 kilometres per second, meaning that β Pictoris b spins significantly faster than any planet in the Solar System, in line with the extrapolation of the known trend in spin velocity with planet mass.

  13. Ambiguity and the 'mental eye' in pictorial relief.

    PubMed

    Koenderink, J J; van Doorn, A J; Kappers, A M; Todd, J T

    2001-01-01

    Photographs of scenes do not determine scenes in the sense that infinitely many different scenes could have given rise to any given photograph. In psychophysical experiments, observers have (at least partially) to resolve these ambiguities. The ambiguities also allow them to vary their response within the space of 'veridical' responses. Such variations may well be called 'the beholder's share' since they do not depend causally on the available depth cues. We determined the pictorial relief for four observers, four stimuli, and four different tasks. In all cases we addressed issues of reliability (scatter on repeated trials) and consistency (how well the data can be explained via a smooth surface, any surface). All data were converted to depth maps which allows us to compare the relief from the different operationalisations. As expected, pictorial relief can differ greatly either between observers (same stimulus, same task) or between operationalisations (same observer, same stimulus). However, when we factor out the essential ambiguity, these differences almost completely vanish and excellent agreement over tasks and observers pertains. Thus, observers often resolve the ambiguity in idiosyncratic ways, but mutually agree--even over tasks--in so far as their responses are causally dependent on the depth cues. A change of task often induces a change in 'mental perspective'. In such cases, the observers switch the 'beholder's share', which resolves the essential ambiguity through a change in viewpoint of their 'mental eye'.

  14. The Variable Ca II Absorption in β Pictoris during 1998

    NASA Astrophysics Data System (ADS)

    Barnes, S. I.; Tobin, William; Pollard, K. R.

    2000-12-01

    Variable absorption features were observed in the visible and ultraviolet spectrum of β Pictoris soon after this star gained attention in the early 1980s due to its large IRAS infrared excess and the discovery, from optical imaging, of an edge-on dust disk. The absorption has been attributed to the evaporation of infalling planetesimals or comet-like bodies (the falling evaporating bodies, or FEB, hypothesis). With a view to confronting this hypothesis with fuller observations, we monitored the Ca II H and K lines in β Pictoris simultaneously during 1998, obtaining sequences of spectra on 50 nights. Variable absorption was usually present. The different oscillator strengths of the H and K lines permit the determination of covering factors, but detailed modelling is required to test whether all features can be explained by the FEB hypothesis. The blend of Ca II H with Balmer H ɛ means that the H and K photospheric profiles are different, and that the variable absorption features do not evolve in parallel. The behaviour of the variable absorption on November 27 is evocative of a body passing in front of the stellar disk in a prograde equatorial orbit.

  15. Deficiency of molecular hydrogen in the disk of beta Pictoris.

    PubMed

    Lecavelier des Etangs, A; Vidal-Madjar, A; Roberge, A; Feldman, P D; Deleuil, M; André, M; Blair, W P; Bouret, J C; Désert, J M; Ferlet, R; Friedman, S; Hébrard, G; Lemoine, M; Moos, H W

    2001-08-16

    Molecular hydrogen (H2) is by far the most abundant material from which stars, protoplanetary disks and giant planets form, but it is difficult to detect directly. Infrared emission lines from H2 have recently been reported towards beta Pictoris, a star harbouring a young planetary system. This star is surrounded by a dusty 'debris disk' that is continuously replenished either by collisions between asteroidal objects or by evaporation of ices on Chiron-like objects. A gaseous disk has also been inferred from absorption lines in the stellar spectrum. Here we present the far-ultraviolet spectrum of beta Pictoris, in which H2 absorption lines are not seen. This allows us to set a very low upper limit on the column density of H2: N(H2) 6 x 10-4. As CO would be destroyed under ambient conditions in about 200 years (refs 9, 11), our result demonstrates that the CO in the disk arises from evaporation of planetesimals.

  16. Measuring pictorial balance perception at first glance using Japanese calligraphy

    PubMed Central

    Gershoni, Sharon; Hochstein, Shaul

    2011-01-01

    According to art theory, pictorial balance acts to unify picture elements into a cohesive composition. For asymmetrical compositions, balancing elements is thought to be similar to balancing mechanical weights in a framework of symmetry axes. Assessment of preference for balance (APB), based on the symmetry-axes framework suggested in Arnheim R, 1974 Art and Visual Perception: A Psychology of the Creative Eye (Berkeley, CA: University of California Press), successfully matched subject balance ratings of images of geometrical shapes over unlimited viewing time. We now examine pictorial balance perception of Japanese calligraphy during first fixation, isolated from later cognitive processes, comparing APB measures with results from balance-rating and comparison tasks. Results show high between-task correlation, but low correlation with APB. We repeated the rating task, expanding the image set to include five rotations of each image, comparing balance perception of artist and novice participant groups. Rotation has no effect on APB balance computation but dramatically affects balance rating, especially for art experts. We analyze the variety of rotation effects and suggest that, rather than depending on element size and position relative to symmetry axes, first fixation balance processing derives from global processes such as grouping of lines and shapes, object recognition, preference for horizontal and vertical elements, closure, and completion, enhanced by vertical symmetry. PMID:23145242

  17. Mammography Prevalence within 2 Two Years (Age 40+) - Small Area Estimates

    Cancer.gov

    For mammography, a woman 40 years of age or older must have reported having at least one mammography in her life. Furthermore, she should have had the most recent one within the last two years by the time of interview.

  18. Mammography screening. Benefits, harms, and informed choice.

    PubMed

    Jørgensen, Karsten Juhl

    2013-04-01

    The rationale for breast cancer screening with mammography is deceptively simple: catch it early and reduce mortality from the disease and the need for mastectomies. But breast cancer is a complex problem, and complex problems rarely have simple solutions. Breast screening brings forward the time of diagnosis only slightly compared to the lifetime of a tumour, and screen-detected tumours have a size where metastases are possible. A key question is if screening can prevent metastases, and if the screen-detected tumours are small enough to allow breast conserving surgery rather than mastectomy. A mortality reduction can never justify a medical intervention in its own right, but must be weighed against the harms. Overdiagnosis is the most important harm of breast screening, but has gained wider recognition only in recent years. Screening leads to the detection and treatment of breast cancers that would otherwise never have been detected because they grow very slowly or not at all and would not have been detected in the woman's lifetime in the absence of screening. Screening therefore turns women into cancer patients unnecessarily, with life-long physical and psychological harms. The debate about the justification of breast screening is therefore not a simple question of whether screening reduces breast cancer mortality. This dissertation quantifies the primary benefits and harms of screening mammography. Denmark has an unscreened "control group" because only two geographical regions offered screening over a long time-period, which is unique in an international context. This was used to study breast cancer mortality, overdiagnosis, and the use of mastectomies. Also, a systematic review of overdiagnosis in five other countries allowed us to show that about half of the screen-detected breast cancers are overdiagnosed. An effect on breast cancer mortality is doubtful in today's setting, and overdiagnosis causes an increase in the use of mastectomies. These findings are

  19. The Assessment of the Likelihood of Mammography Usage with Relevant Factors among Women with Disabilities

    ERIC Educational Resources Information Center

    Kung, Pei-Tseng; Tsai, Wen-Chen; Chiou, Shang-Jyh

    2012-01-01

    Research that identifies the determinants of low mammography use among disabled people is scant. This study examines the determining factors related to the low usage of mammography among women with disabilities. To identify the barriers that prevent women with disabilities from participating in mammography screening can help authorities conceive…

  20. 42 CFR 405.534 - Limitation on payment for screening mammography services.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 2 2010-10-01 2010-10-01 false Limitation on payment for screening mammography... for Determining Reasonable Charges § 405.534 Limitation on payment for screening mammography services... January 1, 1991 until December 31, 2001. Screening mammography services provided after December 31,...

  1. 42 CFR 413.123 - Payment for screening mammography performed by hospitals on an outpatient basis.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 2 2010-10-01 2010-10-01 false Payment for screening mammography performed by... SKILLED NURSING FACILITIES Specific Categories of Costs § 413.123 Payment for screening mammography... mammographies performed by hospitals. (b) Payment to hospitals for outpatient services. Payment to hospitals...

  2. 42 CFR 405.535 - Special rule for nonparticipating physicians and suppliers furnishing screening mammography...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... suppliers furnishing screening mammography services before January 1, 2002. 405.535 Section 405.535 Public... Special rule for nonparticipating physicians and suppliers furnishing screening mammography services before January 1, 2002. The provisions in this section apply for screening mammography services...

  3. Clinical study in phase- contrast mammography: image-quality analysis.

    PubMed

    Longo, Renata; Tonutti, Maura; Rigon, Luigi; Arfelli, Fulvia; Dreossi, Diego; Quai, Elisa; Zanconati, Fabrizio; Castelli, Edoardo; Tromba, Giuliana; Cova, Maria A

    2014-03-06

    The first clinical study of phase-contrast mammography (PCM) with synchrotron radiation was carried out at the Synchrotron Radiation for Medical Physics beamline of the Elettra synchrotron radiation facility in Trieste (Italy) in 2006-2009. The study involved 71 patients with unresolved breast abnormalities after conventional digital mammography and ultrasonography exams carried out at the Radiology Department of Trieste University Hospital. These cases were referred for mammography at the synchrotron radiation facility, with images acquired using a propagation-based phase-contrast imaging technique. To investigate the contribution of phase-contrast effects to the image quality, two experienced radiologists specialized in mammography assessed the visibility of breast abnormalities and of breast glandular structures. The images acquired at the hospital and at the synchrotron radiation facility were compared and graded according to a relative seven-grade visual scoring system. The statistical analysis highlighted that PCM with synchrotron radiation depicts normal structures and abnormal findings with higher image quality with respect to conventional digital mammography.

  4. Response costs of mammography adherence: Iranian women’s perceptions

    PubMed Central

    Khodayarian, Mahsa; Mazloomi-Mahmoodabad, Seyed Saied; Lamyian, Minoor; Morowatisharifabad, Mohammad Ali; Tavangar, Hossein

    2016-01-01

    Background: Mammography as the most common secondary prevention method has known to be helpful in detecting breast cancer at the early stages. Low level of participation among women toward mammography uptake due to cultural beliefs is a great concern. This study aimed at exploring the perceptions of women about response costs of mammography adherence (MA) in Yazd, Iran. Methods: A qualitative study using semi-structured interviews was performed. Fourteen women,one oncology nurse, and a breast cancer survivor were purposefully interviewed. Interviews were transcribed verbatim and analyzed by directed content analysis method based on protection motivation theory (PMT). Results: One main theme was emerged from the analysis namely called "response costs".Two main categories were also emerged from the data; (1) psychological barriers with six subcategories including "embarrassment," "worry about being diagnosed with cancer," "preoccupation with underlying disease," "misconception about mammography," "need for an accompanying person," and "internalizing the experiences of the others," and (2) maladaptive coping modes which encompassed three subcategories: "religious faith," "fatalism," and"avoidance and denial." Conclusion: Useful information was provided about the response costs of mammography utilization based on the perceptions of women. Cognitive barriers may be decreased by conducting modifications in women’s awareness and attitude toward MA as well as changing the national health system infrastructures. Incorporating religious and cultural belief systems into MA educational programs through motivational messages is recommended. PMID:27386423

  5. [Influence of Detector Radiation Damage on CR Mammography Quality Control].

    PubMed

    Moriwaki, Atsumi; Ishii, Mie; Terazono, Shiho; Arao, Keiko; Ishii, Rie; Sanada, Taizo; Yoshida, Akira

    2016-05-01

    Recently, radiation damage to the detector apparatus employed in computed radiography (CR) mammography has become problematic. The CR system and the imaging plate (IP) applied to quality control (QC) program were also used in clinical mammography in our hospital, and the IP to which radiation damage has occurred was used for approximately 5 years (approximately 13,000 exposures). We considered using previously acquired QC image data, which is stored in a server, to investigate the influence of radiation damage to an IP. The mammography unit employed in this study was a phase contrast mammography (PCM) Mermaid (KONICA MINOLTA) system. The QC image was made newly, and it was output in the film, and thereafter the optical density of the step-phantom image was measured. An input (digital value)-output (optical density) conversion curve was plotted using the obtained data. The digital values were then converted to optical density values using a reference optical density vs. digital value curve. When a high radiation dose was applied directly, radiation damage occurred at a position on the IP where no object was present. Daily QC for mammography is conducted using an American College of Radiology (ACR) accreditation phantom and acrylic disc, and an environmental background density measurement is performed as one of the management indexes. In this study, the radiation damage sustained by the acrylic disc was shown to differ from that of the background. Thus, it was revealed that QC results are influenced by radiation damage.

  6. Mammography Findings of Male Breast Diseases

    PubMed Central

    Şafak, Kadihan Yalçın

    2015-01-01

    Over the past 2 decades, the percentage of men presenting with breast complaints has increased from 0.8% to 2.4%, and men now account for 1% of all breast cancer cases. The most common male breast mass is gynecomastia, followed by lipoma and epidermal inclusion cysts. Because there is a paucity of parenchyma as compared with the female breast, the malignancy rapidly progresses to the next stage, with the appearance of secondary signs like nipple retraction, fixation to deeper tissues, skin ulceration or adenopathy. Diagnostic evaluation is needed only when the palpable mass is unilateral, hard, fixed, peripheral to the nipple, or associated with nipple discharge, skin changes, or lymphadenopathy. Male breast cancer usually occurs in a subareolar location or is positioned eccentric to the nipple; occasionally, it occurs in a peripheral position. Secondary signs like skin thickening, nipple retraction, and axillary lymphadenopathy may be seen. Microcalcifications can occur. Mammography can accurately distinguish between malignant and benign male breast disease. Radiologists are generally less familiar with breast disease in males compared with females. In this article, we discuss the clinical, and mammographic features of a variety of benign and malignant diseases that can occur in the male breast.

  7. Image toggling saves time in mammography

    PubMed Central

    Drew, Trafton; Aizenman, Avi M.; Thompson, Matthew B.; Kovacs, Mark D.; Trambert, Michael; Reicher, Murray A.; Wolfe, Jeremy M.

    2015-01-01

    Abstract. When two images are perfectly aligned, even subtle differences are readily detected when the images are “toggled” back and forth in the same location. However, substantial changes between two photographs can be missed if the images are misaligned (“change blindness”). Nevertheless, recent work from our lab, testing nonradiologists, suggests that toggling misaligned photographs leads to superior performance compared to side-by-side viewing (SBS). In order to determine if a benefit of toggling misaligned images may be observed in clinical mammography, we developed an image toggling technique where pairs of new and prior breast imaging exam images could be efficiently toggled back and forth. Twenty-three radiologists read 10 mammograms evenly divided in toggle and SBS modes. The toggle mode led to a 6-s benefit in reaching a decision [t(22)=5.11, p<.05]. The toggle viewing mode also led to a 5% improvement in diagnostic accuracy, though in our small sample this effect was not statistically reliable. Time savings were found even though successive mammograms were not perfectly aligned. Given the ever-increasing caseload for radiologists, this simple manipulation of how the images are viewed could save valuable time in clinical practice, allowing radiologists to read more cases or spend more time on difficult cases. PMID:26870746

  8. Advantages and Disadvantages of Mammography Screening

    PubMed Central

    Heywang-Köbrunner, Sylvia H.; Hacker, Astrid; Sedlacek, Stefan

    2011-01-01

    Summary Mammography screening is the only method presently considered appropriate for mass screening of asymptomatic women. Its frequent use, however, warrants diligent analysis of potential side effects. Radiation risk is far below the natural yearly risk of breast cancer and should not be used as an argument against screening. False-positive calls lead to additional imaging or histopathological assessment, mainly percutaneous breast biopsy. These measures are tolerated and accepted fairly well. Their number is limited by strict quality assurance and constant training. Interval cancers represent a limitation of breast screening that should prompt further research for optimization. Evaluation of overdiagnosis is a highly debated topic in the literature. According to the probably most realistic available calculations, overdiagnosis is acceptable as it is compensated by the potential mortality reduction. Nonetheless, this potential side effect warrants optimal adjustment of therapy to the patient's individual risk. The mortality reduction seen in randomized studies was confirmed by results from national screening programs. A recent case referent study indicated that improvements in mortality reduction run parallel to improved mammographic techniques. Use of less aggressive therapies is another valuable effect of screening. Awareness of potential problems, strict quality assurance, and further research should help to further develop screening programs. PMID:21779225

  9. Feasibility of using LODOX technology for mammography

    NASA Astrophysics Data System (ADS)

    Lease, Alyson; Vaughan, Christopher; Beningfield, Stephan; Potgieter, Herman; Booysen, Andre

    2002-05-01

    The LODOX (Low Dose X-ray) Scanner, created by De Beers, is currently being clinically tested at the Trauma Unit of Groote Schuur Hospital and the University of Cape Town in South Africa. High quality images with exceedingly low radiation suggest that the technology may also be used to identify breast cancer lesions and microcalcifications. The measured LODOX modulation transfer function averages 6 percent at 10 cycles per millimeter, while the detected quantum efficiency is approximately 25 percent at 1 cycle per millimeter. The mean glandular doses calculated for a breast thickness of 4 cm at various intensities -- ranging from 0.022 rad at 70mAs to 0.043 rad at 125mAs -- were approximately 10 times less than the value designated by the American College of Radiology (0.3 rad per breast image). At 40kV, LODOX exhibits an average half value layer of 1.59 mm of Al (compared to 0.3 to 0.4 mm recommended for mammography), illustrating the unfavorable higher penetration of LODOX X-rays. The extremely low radiation dose delivered by the LODOX suggests that the technology would be feasible for detecting and diagnosing cancers in the sensitive tissue of the breast, once adjustments to X-ray range and beam hardness had been accomplished.

  10. Essays on the Economics of Higher Education

    ERIC Educational Resources Information Center

    Tang, Hui-Hsuan

    2012-01-01

    This dissertation is comprised of two essays that broadly consider the role human capital plays in the matching process between individuals and institutions and builds on prior education literature that has found growing evidence that economic choices and opportunities are inextricably linked to human capital investment. The essays in this…

  11. Constitution 200: A Bicentennial Collection of Essays.

    ERIC Educational Resources Information Center

    Hepburn, Mary A., Ed.; And Others

    Constitutional essays which formed the basis of public assemblies throughout three states are compiled in this book. The first three essays consider the U.S. government principles of federalism, judicial review, and the separation of powers. Michael L. Benedict proposes that the question of ultimate sovereignty has been answered differently by…

  12. Essays on La Mujer. Anthology No. 1.

    ERIC Educational Resources Information Center

    Sanchez, Rosaura, Ed.; Cruz, Rosa Martinez, Ed.

    The 10 essays introduce some concepts and topics of particular concern and interest to those wishing to analyze the situation of the Chicana within her particular historical, social and economical context. Topics of the essays are: (1) the Chicana labor force; (2) the role of the Chicana within the student movement; (3) the Chicana and the Chicano…

  13. Cohesion and Coherence in Short Expository Essays.

    ERIC Educational Resources Information Center

    Lindeberg, Ann-Charlotte

    A study to find patterns of cohesion and rhetorical structure that distinguish good from weak English essay writing is described. The corpus consisted of ten Swedish college essays written as part of the final exam in a first-year English course. Methodological problems encountered included the delimitation of units for the analysis of cohesive…

  14. The "New" Age: A Bibliographic Essay.

    ERIC Educational Resources Information Center

    Chandler, Daniel Ross

    This bibliographic essay describes and discusses important books in a variety of thematic areas associated with the New Age Movement, which is a distinctive communicative phenomenon characterized by unconventional beliefs and activities. The essay argues that the single subject pervading the peculiar phenomena and puzzling thoughtful critics is…

  15. Framing the Past; Essays on Art Education.

    ERIC Educational Resources Information Center

    Soucy, Donald, Ed.; Stankiewicz, Mary Ann, Ed.

    This collection of essays presents the history of art education from a variety of perspectives. Traditional and revisionist issues are seen from broad overviews and through specific concerns. Textual analysis, cultural transmission, and prominent philosophies are discussed. Thirteen essays include: (1) "A History of Art Education…

  16. The Photographic Essay in Geographic Instruction

    ERIC Educational Resources Information Center

    Meyer, Douglas K.

    1973-01-01

    In this paper a media technique, the photographic essay, is examined and suggested for use in geographic education. The procedures for planning and executing photographic essays using slides are explained. Attention is given to establishing objectives and organizing slides accordingly for effective learning. Basid principles of photographic…

  17. Methodological Approaches to Online Scoring of Essays.

    ERIC Educational Resources Information Center

    Chung, Gregory K. W. K.; O'Neil, Harold F., Jr.

    This report examines the feasibility of scoring essays using computer-based techniques. Essays have been incorporated into many of the standardized testing programs. Issues of validity and reliability must be addressed to deploy automated approaches to scoring fully. Two approaches that have been used to classify documents, surface- and word-based…

  18. English Transported: Essays on Australasian English.

    ERIC Educational Resources Information Center

    Ramson, W. S., Ed.

    This collection of essays on Australasian English deals with various aspects of the language as it is spoken in the areas of Australian, New Zealand, and Papua-New Guinea. Although the bulk of the essays are concerned with Australian and New Zealand English, the editor expresses the hope that the integrated study of these two major dialects will…

  19. 2012 Cliff Weiss Memorial Essay Contest Winners

    ERIC Educational Resources Information Center

    Techniques: Connecting Education and Careers (J3), 2012

    2012-01-01

    This article presents the winners of the 2012 Cliff Weiss Memorial Essay Contest. They are Naim Owens from Washington, DC, and Colissa Menke from Warrensburg, Missouri. The 2012 essay topic is "How do you feel CTE prepares individuals, including yourself, for a future career?"

  20. Students' Experiences with an Automated Essay Scorer

    ERIC Educational Resources Information Center

    Scharber, Cassandra; Dexter, Sara; Riedel, Eric

    2008-01-01

    The purpose of this research is to analyze preservice teachers' use of and reactions to an automated essay scorer used within an online, case-based learning environment called ETIPS. Data analyzed include post-assignment surveys, a user log of students' actions within the cases, instructor-assigned scores on final essays, and interviews with four…

  1. Indian Education in America: 8 Essays.

    ERIC Educational Resources Information Center

    Deloria, Vine, Jr.

    This book presents eight essays by Vine Deloria, Jr., a Standing Rock Sioux and professor of political science at the University of Colorado. Essays examine issues facing Native American students as they progress through the educational system, and aim to help Indian students place Western knowledge into the context of tribal and community…

  2. Autoscoring Essays Based on Complex Networks

    ERIC Educational Resources Information Center

    Ke, Xiaohua; Zeng, Yongqiang; Luo, Haijiao

    2016-01-01

    This article presents a novel method, the Complex Dynamics Essay Scorer (CDES), for automated essay scoring using complex network features. Texts produced by college students in China were represented as scale-free networks (e.g., a word adjacency model) from which typical network features, such as the in-/out-degrees, clustering coefficient (CC),…

  3. A pictorial review of hypovolaemic shock in adults.

    PubMed

    Tarrant, A M; Ryan, M F; Hamilton, P A; Benjaminov, O

    2008-03-01

    Hypovolaemic shock is an infrequently encountered entity found on CT of victims of severe trauma. Early abdominal and pelvic CT can show diffuse abnormalities owing to hypovolaemia that may alert radiologists to the presence of hypovolaemic shock. In this pictorial review, we present the imaging findings of hypovolaemic shock, as seen on CT of the abdomen. A spectrum of vascular and visceral CT signs is described. Vascular signs include diminished inferior vena cava diameter, diminished aortic diameter and abnormal vascular enhancement. Hollow visceral abnormalities include diffuse increased mucosal enhancement of both the small and large bowel, diffuse thickening of the small bowel wall, and small bowel dilatation. Solid visceral abnormalities include both decreased and increased end organ enhancement. This report should increase radiologists' awareness of the CT manifestations of hypovolaemic shock.

  4. Formation and dynamical history of the beta Pictoris system

    NASA Astrophysics Data System (ADS)

    Wyatt, M.

    2014-09-01

    The structure of the beta Pic disk holds many clues to its formation and dynamical history. In particular there is strong evidence for sculpting by the beta Pic-b planet. For example, a warp in the disk at 80au is thought to be driven by the secular perturbations of that planet, and scattering of comets by beta Pic-b is thought to be the origin of the Falling Evaporating Bodies. A clump in the disk coincident with the warp, also at ~80au, provides clues to the outer planetary system which for now is poorly constrained. One possible origin for the clump is in trapping of comets into resonance with an outer planet currently at ~60au, with an alternative scenario being a giant impact between planetary embryos. This talk will consider the various disk structures and what they tell us about the formation and dynamical history of the beta Pictoris system.

  5. Rare metastases of differentiated thyroid carcinoma: pictorial review.

    PubMed

    Song, Hong-Jun; Xue, Yan-Li; Xu, Yan-Hong; Qiu, Zhong-Ling; Luo, Quan-Yong

    2011-10-01

    Differentiated thyroid cancer (DTC) is usually indolent with good prognosis and long-term survival. However, DTC distant metastasis is often a grave event and accounts for most of its disease-specific mortality. The major sites of distant metastases are the lung and bone. Metastases to the brain, breast, liver, kidney, muscle, and skin are rare or relatively rare. Nevertheless, recognizing rare metastases from DTC has a significant impact on the clinical decision making and prognosis of patients. (131)I single photon emission computed tomography/computed tomography ((131)I-SPECT/CT) can provide both metabolic and anatomic information about a lesion; therefore, it can better localize and define the (131)I-WBS findings in DTC patients. In this pictorial review, the imaging features of a range of rare metastases from DTC are demonstrated, with a particular emphasis on the (131)I-SPECT/CT diagnostic aspect.

  6. Patterns and determinants of mammography screening in Lebanese women.

    PubMed

    Elias, Nadia; Bou-Orm, Ibrahim R; Adib, Salim M

    2017-03-01

    The associations of ever using and/or repeating a mammography test with psychosocial and socio-demographic factors were surveyed in 2014 among Lebanese women ≥ 40. A sample of 2400 women was selected across Lebanon. Variables with significant bivariate associations with various types of behaviors were entered in multivariate analysis. Of the total, 105 women (4·4%) had never heard of mammography as a tool for early breast cancer detection. Among the remaining 2295, 45% had ever used it, of whom 10% had obtained it for the first time within the 12 months preceding the survey. Repeaters were 67% of 926 women who had the time opportunity to do so (median lifetime frequency: 2). Older age, higher socio-economic status (SES) and living within the Greater Beirut (GB) area were significantly associated with ever-use. Within GB, psychosocial factors such as perceived susceptibility and benefits were most strongly associated with ever-use. Outside GB, socio-economic advantage seemed to mostly affect ever-use. Only 4% reported opposition from husbands to their mammography, and husband's support was significant for adherence to mammography guidelines mostly outside GB. Higher education emerged also as a significant socio-demographic determinant for ever-repeating in all regions. Perceived comfort of the previous test strongly affected the likelihood of repeating it. Providing mammography free-of-charge may alleviate some obstacles among women with socio-economic disadvantage. Stressing that good results one year do not make the cancer less likely or repeating the test less important, as well as improving the comfort of mammography testing could ensure test repeating.

  7. Quantification of breast arterial calcification using full field digital mammography.

    PubMed

    Molloi, Sabee; Xu, Tong; Ducote, Justin; Iribarren, Carlos

    2008-04-01

    Breast arterial calcification is commonly detected on some mammograms. Previous studies indicate that breast arterial calcification is evidence of general atherosclerotic vascular disease and it may be a useful marker of coronary artery disease. It can potentially be a useful tool for assessment of coronary artery disease in women since mammography is widely used as a screening tool for early detection of breast cancer. However, there are currently no available techniques for quantification of calcium mass using mammography. The purpose of this study was to determine whether it is possible to quantify breast arterial calcium mass using standard digital mammography. An anthropomorphic breast phantom along with a vessel calcification phantom was imaged using a full field digital mammography system. Densitometry was used to quantify calcium mass. A calcium calibration measurement was performed at each phantom thickness and beam energy. The known (K) and measured (M) calcium mass on 5 and 9 cm thickness phantoms were related by M=0.964K -0.288 mg (r=0.997 and SEE=0.878 mg) and M=1.004K+0.324 mg (r=0.994 and SEE = 1.32 mg), respectively. The results indicate that accurate calcium mass measurements can be made without correction for scatter glare as long as careful calcium calibration is made for each breast thickness. The results also indicate that composition variations and differences of approximately 1 cm between calibration phantom and breast thickness introduce only minimal error in calcium measurement. The uncertainty in magnification is expected to cause up to 5% and 15% error in calcium mass for 5 and 9 cm breast thicknesses, respectively. In conclusion, a densitometry technique for quantification of breast arterial calcium mass was validated using standard full field digital mammography. The results demonstrated the feasibility and potential utility of the densitometry technique for accurate quantification of breast arterial calcium mass using standard digital

  8. Quantification of breast arterial calcification using full field digital mammography

    PubMed Central

    Molloi, Sabee; Xu, Tong; Ducote, Justin; Iribarren, Carlos

    2008-01-01

    Breast arterial calcification is commonly detected on some mammograms. Previous studies indicate that breast arterial calcification is evidence of general atherosclerotic vascular disease and it may be a useful marker of coronary artery disease. It can potentially be a useful tool for assessment of coronary artery disease in women since mammography is widely used as a screening tool for early detection of breast cancer. However, there are currently no available techniques for quantification of calcium mass using mammography. The purpose of this study was to determine whether it is possible to quantify breast arterial calcium mass using standard digital mammography. An anthropomorphic breast phantom along with a vessel calcification phantom was imaged using a full field digital mammography system. Densitometry was used to quantify calcium mass. A calcium calibration measurement was performed at each phantom thickness and beam energy. The known (K) and measured (M) calcium mass on 5 and 9 cm thickness phantoms were related by M=0.964K−0.288 mg (r=0.997 and SEE=0.878 mg) and M=1.004K+0.324 mg (r=0.994 and SEE=1.32 mg), respectively. The results indicate that accurate calcium mass measurements can be made without correction for scatter glare as long as careful calcium calibration is made for each breast thickness. The results also indicate that composition variations and differences of approximately 1 cm between calibration phantom and breast thickness introduce only minimal error in calcium measurement. The uncertainty in magnification is expected to cause up to 5% and 15% error in calcium mass for 5 and 9 cm breast thicknesses, respectively. In conclusion, a densitometry technique for quantification of breast arterial calcium mass was validated using standard full field digital mammography. The results demonstrated the feasibility and potential utility of the densitometry technique for accurate quantification of breast arterial calcium mass using standard digital

  9. Quantification of breast arterial calcification using full field digital mammography

    SciTech Connect

    Molloi, Sabee; Xu Tong; Ducote, Justin; Iribarren, Carlos

    2008-04-15

    Breast arterial calcification is commonly detected on some mammograms. Previous studies indicate that breast arterial calcification is evidence of general atherosclerotic vascular disease and it may be a useful marker of coronary artery disease. It can potentially be a useful tool for assessment of coronary artery disease in women since mammography is widely used as a screening tool for early detection of breast cancer. However, there are currently no available techniques for quantification of calcium mass using mammography. The purpose of this study was to determine whether it is possible to quantify breast arterial calcium mass using standard digital mammography. An anthropomorphic breast phantom along with a vessel calcification phantom was imaged using a full field digital mammography system. Densitometry was used to quantify calcium mass. A calcium calibration measurement was performed at each phantom thickness and beam energy. The known (K) and measured (M) calcium mass on 5 and 9 cm thickness phantoms were related by M=0.964K-0.288 mg (r=0.997 and SEE=0.878 mg) and M=1.004K+0.324 mg (r=0.994 and SEE=1.32 mg), respectively. The results indicate that accurate calcium mass measurements can be made without correction for scatter glare as long as careful calcium calibration is made for each breast thickness. The results also indicate that composition variations and differences of approximately 1 cm between calibration phantom and breast thickness introduce only minimal error in calcium measurement. The uncertainty in magnification is expected to cause up to 5% and 15% error in calcium mass for 5 and 9 cm breast thicknesses, respectively. In conclusion, a densitometry technique for quantification of breast arterial calcium mass was validated using standard full field digital mammography. The results demonstrated the feasibility and potential utility of the densitometry technique for accurate quantification of breast arterial calcium mass using standard digital

  10. Three essays on access pricing

    NASA Astrophysics Data System (ADS)

    Sydee, Ahmed Nasim

    In the first essay, a theoretical model is developed to determine the time path of optimal access price in the telecommunications industry. Determining the optimal access price is an important issue in the economics of telecommunications. Setting a high access price discourages potential entrants; a low access price, on the other hand, amounts to confiscation of private property because the infrastructure already built by the incumbent is sunk. Furthermore, a low access price does not give the incumbent incentives to maintain the current network and to invest in new infrastructures. Much of the existing literature on access pricing suffers either from the limitations of a static framework or from the assumption that all costs are avoidable. The telecommunications industry is subject to high stranded costs and, therefore, to address this issue a dynamic model is imperative. This essay presents a dynamic model of one-way access pricing in which the compensation involved in deregulatory taking is formalized and then analyzed. The short run adjustment after deregulatory taking has occurred is carried out and discussed. The long run equilibrium is also analyzed. A time path for the Ramsey price is shown as the correct dynamic price of access. In the second essay, a theoretical model is developed to determine the time path of optimal access price for an infrastructure that is characterized by congestion and lumpy investment. Much of the theoretical literature on access pricing of infrastructure prescribes that the access price be set at the marginal cost of the infrastructure. In proposing this rule of access pricing, the conventional analysis assumes that infrastructure investments are infinitely divisible so that it makes sense to talk about the marginal cost of investment. Often it is the case that investments in infrastructure are lumpy and can only be made in large chunks, and this renders the marginal cost concept meaningless. In this essay, we formalize a model of

  11. Mammography use and mode of detection among breast cancer patients in Estonia.

    PubMed

    Innos, Kaire; Valvere, Vahur; Padrik, Peeter; Eelma, Evelyn; Kütner, Riina; Lehtsaar, Jaak; Tekkel, Mare

    2016-01-01

    The aim of this study was to examine past mammography use and mode of detection among breast cancer (BC) patients in Estonia, a country that has low screening coverage and high BC mortality. Women newly diagnosed with primary BC in Estonia in 2008-2010 were interviewed. Determinants of past mammography use and the detection of BC by mammography were studied using multivariate logistic regression. Among 977 participants, almost half reported no mammograms prior to the detection of BC. Overall, 22% of the cases were detected by mammography (16% by screening mammography). Detection by mammography was strongly related to age, past mammography use, and obesity. Among cases detected by mammography, 10% were stage III/IV at diagnosis (32% among cases detected by other modes). This study showed low mammography utilization and high rate of self-detection of BC in Estonia. Increased detection by mammography would help diagnose the disease at an earlier stage and consequently avoid premature BC deaths. Efforts should be undertaken to increase participation in screening and improve the availability of mammography among older and high-risk women. The results are likely to be relevant for other countries and population groups with low screening coverage.

  12. Positron Emission Mammography with Multiple Angle Acquisition

    SciTech Connect

    Mark F. Smith; Stan Majewski; Raymond R. Raylman

    2002-11-01

    Positron emission mammography (PEM) of F-18 fluorodeoxyglucose (FDG) uptake in breast tumors with dedicated detectors typically has been accomplished with two planar detectors in a fixed position with the breast under compression. The potential use of PEM imaging at two detector positions to guide stereotactic breast biopsy has motivated us to use PEM coincidence data acquired at two or more detector positions together in a single image reconstruction. Multiple angle PEM acquisition and iterative image reconstruction were investigated using point source and compressed breast phantom acquisitions with 5, 9, 12 and 15 mm diameter spheres and a simulated tumor:background activity concentration ratio of 6:1. Image reconstruction was performed with an iterative MLEM algorithm that used coincidence events between any two detector pixels on opposed detector heads at each detector position. This present study compared two acquisition protocols: 2 angle acquisition with detector angular positions of -15 and +15 degrees and 11 angle acquisition with detector positions spaced at 3 degree increments over the range -15 to +15 degrees. Three- dimensional image resolution was assessed for the point source acquisitions, and contrast and signal-to-noise metrics were evaluated for the compressed breast phantom with different simulated tumor sizes. Radial and tangential resolutions were similar for the two protocols, while normal resolution was better for the 2 angle acquisition. Analysis is complicated by the asymmetric point spread functions. Signal- to-noise vs. contrast tradeoffs were better for 11 angle acquisition for the smallest visible 9 mm sphere, while tradeoff results were mixed for the larger and more easily visible 12 mm and 15 mm diameter spheres. Additional study is needed to better understand the performance of limited angle tomography for PEM. PEM tomography experiments with complete angular sampling are planned.

  13. Positron Emission Mammography with Multiple Angle Acquisition

    SciTech Connect

    Mark F. Smith; Stan Majewski; Raymond R. Raylman

    2002-11-01

    Positron emission mammography (PEM) of F-18 fluorodeoxyglucose (FbG) uptake in breast tumors with dedicated detectors typically has been accomplished with two planar detectors in a fixed position with the breast under compression. The potential use of PEM imaging at two detector positions to guide stereotactic breast biopsy has motivated us to use PEM coincidence data acquired at two or more detector positions together in a single image reconstruction. Multiple angle PEM acquisition and iterative image reconstruction were investigated using point source and compressed breast phantom acquisitions with 5, 9, 12 and 15 mm diameter spheres and a simulated tumor:background activity concentration ratio of 6:1. Image reconstruction was performed with an iterative MLEM algorithm that used coincidence events between any two detector pixels on opposed detector heads at each detector position. This present study compared two acquisition protocols: 2 angle acquisition with detector angular positions of -15 and +15 degrees and 11 angle acquisition with detector positions spaced at 3 degree increments over the range -15 to +15 degrees. Three-dimensional image resolution was assessed for the point source acquisitions, and contrast and signal-to-noise metrics were evaluated for the compressed breast phantom with different simulated tumor sizes. Radial and tangential resolutions were similar for the two protocols, while normal resolution was better for the 2 angle acquisition. Analysis is complicated by the asymmetric point spread functions. Signal- to-noise vs. contrast tradeoffs were better for 11 angle acquisition for the smallest visible 9 mm sphere, while tradeoff results were mixed for the larger and more easily visible 12 mm and 15 mm diameter spheres. Additional study is needed to better understand the performance of limited angle tomography for PEM. PEM tomography experiments with complete angular sampling are planned.

  14. Uncertainty modeling for ontology-based mammography annotation with intelligent BI-RADS scoring.

    PubMed

    Bulu, Hakan; Alpkocak, Adil; Balci, Pinar

    2013-05-01

    This paper presents an ontology-based annotation system and BI-RADS (Breast Imaging Reporting and Data System) score reasoning with Semantic Web technologies in mammography. The annotation system is based on the Mammography Annotation Ontology (MAO) where the BI-RADS score reasoning works. However, ontologies are based on crisp logic and they cannot handle uncertainty. Consequently, we propose a Bayesian-based approach to model uncertainty in mammography ontology and make reasoning possible using BI-RADS scores with SQWRL (Semantic Query-enhanced Web Rule Language). First, we give general information about our system and present details of mammography annotation ontology, its main concepts and relationships. Then, we express uncertainty in mammography and present approaches to handle uncertainty issues. System is evaluated with a manually annotated dataset DEMS (Dokuz Eylul University Mammography Set) and DDSM (Digital Database for Screening Mammography). We give the result of experimentations in terms of accuracy, sensitivity, precision and uncertainty level measures.

  15. The impact of a physician intervention program on older women's mammography use.

    PubMed

    Preston, J A; Grady, J N; Schulz, A F; Petrillo, M K; Scinto, J D

    1998-12-01

    The Mammography Optimum Referral Effort (MORE) is a physician office-based intervention program initiated by the Connecticut Peer Review Organization (CPRO) to increase mammography use among older women in Connecticut. Three locales in the state were targeted for the MORE intervention based on identified low mammography rates in women aged 65 years and older. Thirty-seven physicians participated from March 1, 1996, to August 31, 1996. Annual mammography rates were derived by merging Medicare Part B mammography claims with a database from the Connecticut Tumor Registry. This strategy allowed us to exclude women with a prior history of breast cancer from the analysis, in order to estimate screening rates. The MORE intervention was associated with an absolute increase of 5.9%, which represents a relative increase of 15.4%, in annual mammography use. Our findings suggest that a multifaceted physician intervention is capable of increasing mammography use among older women.

  16. Pictorial cigarette pack warnings: a meta-analysis of experimental studies

    PubMed Central

    Noar, Seth M; Hall, Marissa G; Francis, Diane B; Ribisl, Kurt M; Pepper, Jessica K; Brewer, Noel T

    2016-01-01

    Objective To inform international research and policy, we conducted a meta-analysis of the experimental literature on pictorial cigarette pack warnings. Data sources We systematically searched 7 computerised databases in April 2013 using several search terms. We also searched reference lists of relevant articles. Study selection We included studies that used an experimental protocol to test cigarette pack warnings and reported data on both pictorial and text-only conditions. 37 studies with data on 48 independent samples (N=33 613) met criteria. Data extraction and synthesis Two independent coders coded all study characteristics. Effect sizes were computed from data extracted from study reports and were combined using random effects meta-analytic procedures. Results Pictorial warnings were more effective than text-only warnings for 12 of 17 effectiveness outcomes (all p<0.05). Relative to text-only warnings, pictorial warnings (1) attracted and held attention better; (2) garnered stronger cognitive and emotional reactions; (3) elicited more negative pack attitudes and negative smoking attitudes and (4) more effectively increased intentions to not start smoking and to quit smoking. Participants also perceived pictorial warnings as being more effective than text-only warnings across all 8 perceived effectiveness outcomes. Conclusions The evidence from this international body of literature supports pictorial cigarette pack warnings as more effective than text-only warnings. Gaps in the literature include a lack of assessment of smoking behaviour and a dearth of theory-based research on how warnings exert their effects. PMID:25948713

  17. ``Water Drops'' Essays Available for Public Radio

    NASA Astrophysics Data System (ADS)

    Black, Peter E.

    2007-11-01

    ``Water Drops'' are 90-second essays on water science, hydrology, culture, history, organizations, law, and policy that have aired weekly on radio station WRVO-FM in Oswego, N.Y., since January 2006. Created for the lay public with a basic understanding of Earth science, the 133 essays now are available on Public Radio Exchange (http://www.prx.org) for free use by public radio stations, according to terms set forth at the Exchange Web site that include citing appropriate credits. If aired weekly, there are enough essays for 2.5 years of radio programming.

  18. Technology evaluation center assessment synopsis: full-field digital mammography.

    PubMed

    Rothenberg, Barbara M; Ziegler, Kathleen M; Aronson, Naomi

    2006-08-01

    Full-field digital mammography (FFDM) is proposed as an alternative to screen-film mammography (SFM). The ability to separate and optimize the acquisition, storage, and display of images may allow greater visualization of breast cancers at equal or lower radiation doses, especially in younger women and those with denser breasts. This is a synopsis of a systematic review by the Blue Cross Blue Shield Association Technology Evaluation Center. This updated systematic review primarily incorporated the results of the ACR Imaging Network(R) Digital Mammographic Imaging Screening Trial (DMIST), which provided results on 42,760 asymptomatic women who underwent both FFDM and SFM and showed with reasonable certainty that there was no difference in the accuracy of the 2 modalities for asymptomatic women in general, with some advantages of FFDM in certain subgroups. There were no strong, new studies on the use of digital mammography compared with film mammography in a diagnostic population. However, the DMIST results indicated that tumors detected by FFDM, but not by SFM, were likely to be invasive carcinomas or medium-grade to high-grade ductal carcinoma in situ. On the basis of the suppositions that these are the cancers of greatest interest and the ones more likely to be found in a diagnostic population and that the diagnostic population may be younger on average than the screening population, it was concluded that there is sufficient evidence to support the use of FFDM for diagnostic purposes.

  19. Artificial Neural Networks in Mammography Interpretation and Diagnostic Decision Making

    PubMed Central

    Burnside, Elizabeth S.

    2013-01-01

    Screening mammography is the most effective means for early detection of breast cancer. Although general rules for discriminating malignant and benign lesions exist, radiologists are unable to perfectly detect and classify all lesions as malignant and benign, for many reasons which include, but are not limited to, overlap of features that distinguish malignancy, difficulty in estimating disease risk, and variability in recommended management. When predictive variables are numerous and interact, ad hoc decision making strategies based on experience and memory may lead to systematic errors and variability in practice. The integration of computer models to help radiologists increase the accuracy of mammography examinations in diagnostic decision making has gained increasing attention in the last two decades. In this study, we provide an overview of one of the most commonly used models, artificial neural networks (ANNs), in mammography interpretation and diagnostic decision making and discuss important features in mammography interpretation. We conclude by discussing several common limitations of existing research on ANN-based detection and diagnostic models and provide possible future research directions. PMID:23781276

  20. An equivalent relative utility metric for evaluating screening mammography.

    PubMed

    Abbey, Craig K; Eckstein, Miguel P; Boone, John M

    2010-01-01

    Comparative studies of performance in screening mammography are often ambiguous. A new method will frequently show a higher sensitivity or detection rate than an existing standard with a concomitant increase in false positives or recalls. The authors propose an equivalent relative utility (ERU) metric based on signal detection theory to quantify screening performance in such comparisons. The metric is defined as the relative utility, as defined in classical signal detection theory, needed to make 2 systems equivalent. ERU avoids the problem of requiring a predefined putative relative utility, which has limited application of utility theory in receiver operating characteristic analysis. The metric can be readily estimated from recall and detection rates commonly reported in comparative clinical studies. An important practical advantage of ERU is that in prevalence matched populations, the measure can be estimated without an independent estimate of disease prevalence. Thus estimating ERU does not require a study with long-term follow-up to find cases of missed disease. The approach is applicable to any comparative screening study that reports results in terms of recall and detection rates, although the authors focus exclusively on screening mammography in this work. They derive the ERU from the definition of utility given in classical treatments of signal detection theory. They also investigate reasonable values of relative utility in screening mammography for use in interpreting ERU using data from a large clinical study. As examples of application of ERU, they reanalyze 2 recently published reports using recall and detection rates in screening mammography.

  1. Impact of screening mammography on breast cancer mortality.

    PubMed

    Bleyer, Archie; Baines, Cornelia; Miller, Anthony B

    2016-04-15

    The degree to which observed reductions in breast cancer mortality is attributable to screening mammography has become increasingly controversial. We examined this issue with three fundamentally different approaches: (i) Chronology--the temporal relationship of the onset of breast cancer mortality decline and the national implementation of screening mammography; (ii) Magnitude--the degree to which breast cancer mortality declined relative to the amount (penetration) of screening mammography; (iii) Analogy--the pattern of mortality rate reductions of other cancers for which population screening is not conducted. Chronology and magnitude were assessed with data from Europe and North America, with three methods applied to magnitude. A comparison of eight countries in Europe and North America does not demonstrate a correlation between the penetration of national screening and either the chronology or magnitude of national breast cancer mortality reduction. In the United States, the magnitude of the mortality decline is greater in the unscreened, younger women than in the screened population and regional variation in the rate of breast cancer mortality reduction is not correlated with screening penetrance, either as self-reported or by the magnitude of screening-induced increase in early-stage disease. Analogy analysis of United States data identifies 14 other cancers with a similar distinct onset of mortality reduction for which screening is not performed. These five lines of evidence from three different approaches and additional observations discussed do not support the hypothesis that mammography screening is a primary reason for the breast cancer mortality reduction in Europe and North America.

  2. Three essays on utility regulation

    NASA Astrophysics Data System (ADS)

    Hlasny, Vladimir

    To induce utilities in the gas distribution market to operate efficiently, US states have deployed consumer choice programs, price caps, and variations of sliding scale plans. My first essay studies the impact of these restructuring and deregulation efforts on consumer rates, using panel data from a custom survey of state commissions and the Department of Energy. I estimate the residential, small commercial and industrial price equations jointly, and use instrumental variables to control for the potentially endogenous demand and status of deregulation. Consumer choice programs lower the prices by 2.2-20.1% compared to the rate of return regulation, benefiting industrial consumers the most and households the least. These effects appear even one to two years prior to the programs' implementation, and become stronger over time. Price caps lower all prices by 0.0-20.0%, with the same ranking. The impacts of sliding scale plans are close to zero, between -2.6% and +4.0% The second paper evaluates health damages caused by air concentrations of SO2 under three alternative environmental policies leading to identical aggregate emissions: emission caps, a nationwide emission tax, and a system of tradable emission allowances such as the one currently used in the US. The numerical model of the industry finds generators' output, participation in energy trade and SO2 abatement effort under each policy. The resulting SO2 concentrations are used to derive the aggregate health damages using estimates in the medical literature. SO2 concentrations vary across policies even when the aggregate emissions are the same. These variations translate into substantially different losses for any individual state, and, nationwide, to hundreds of millions of dollars of difference in aggregate damages. Emission caps are found to lead to the lowest damages, outperforming the currently used system of allowances by 452 million. A uniform emission tax leads to very similar damages as the system of

  3. Struggling with Fitzgerald's "Crack-Up" Essays.

    ERIC Educational Resources Information Center

    Fulcher, James

    1998-01-01

    Ponders F. Scott Fitzgerald's essays about his "crack-up" and relates them to the many complex aspects of the struggles of a teacher using post-structural literary theory and teaching two-year college students. (SR)

  4. Postmortem validation of breast density using dual-energy mammography

    PubMed Central

    Molloi, Sabee; Ducote, Justin L.; Ding, Huanjun; Feig, Stephen A.

    2014-01-01

    Purpose: Mammographic density has been shown to be an indicator of breast cancer risk and also reduces the sensitivity of screening mammography. Currently, there is no accepted standard for measuring breast density. Dual energy mammography has been proposed as a technique for accurate measurement of breast density. The purpose of this study is to validate its accuracy in postmortem breasts and compare it with other existing techniques. Methods: Forty postmortem breasts were imaged using a dual energy mammography system. Glandular and adipose equivalent phantoms of uniform thickness were used to calibrate a dual energy basis decomposition algorithm. Dual energy decomposition was applied after scatter correction to calculate breast density. Breast density was also estimated using radiologist reader assessment, standard histogram thresholding and a fuzzy C-mean algorithm. Chemical analysis was used as the reference standard to assess the accuracy of different techniques to measure breast composition. Results: Breast density measurements using radiologist reader assessment, standard histogram thresholding, fuzzy C-mean algorithm, and dual energy were in good agreement with the measured fibroglandular volume fraction using chemical analysis. The standard error estimates using radiologist reader assessment, standard histogram thresholding, fuzzy C-mean, and dual energy were 9.9%, 8.6%, 7.2%, and 4.7%, respectively. Conclusions: The results indicate that dual energy mammography can be used to accurately measure breast density. The variability in breast density estimation using dual energy mammography was lower than reader assessment rankings, standard histogram thresholding, and fuzzy C-mean algorithm. Improved quantification of breast density is expected to further enhance its utility as a risk factor for breast cancer. PMID:25086548

  5. Postmortem validation of breast density using dual-energy mammography

    SciTech Connect

    Molloi, Sabee Ducote, Justin L.; Ding, Huanjun; Feig, Stephen A.

    2014-08-15

    Purpose: Mammographic density has been shown to be an indicator of breast cancer risk and also reduces the sensitivity of screening mammography. Currently, there is no accepted standard for measuring breast density. Dual energy mammography has been proposed as a technique for accurate measurement of breast density. The purpose of this study is to validate its accuracy in postmortem breasts and compare it with other existing techniques. Methods: Forty postmortem breasts were imaged using a dual energy mammography system. Glandular and adipose equivalent phantoms of uniform thickness were used to calibrate a dual energy basis decomposition algorithm. Dual energy decomposition was applied after scatter correction to calculate breast density. Breast density was also estimated using radiologist reader assessment, standard histogram thresholding and a fuzzy C-mean algorithm. Chemical analysis was used as the reference standard to assess the accuracy of different techniques to measure breast composition. Results: Breast density measurements using radiologist reader assessment, standard histogram thresholding, fuzzy C-mean algorithm, and dual energy were in good agreement with the measured fibroglandular volume fraction using chemical analysis. The standard error estimates using radiologist reader assessment, standard histogram thresholding, fuzzy C-mean, and dual energy were 9.9%, 8.6%, 7.2%, and 4.7%, respectively. Conclusions: The results indicate that dual energy mammography can be used to accurately measure breast density. The variability in breast density estimation using dual energy mammography was lower than reader assessment rankings, standard histogram thresholding, and fuzzy C-mean algorithm. Improved quantification of breast density is expected to further enhance its utility as a risk factor for breast cancer.

  6. [The attitude before subclinical breast lesions on mammography].

    PubMed

    Blidaru, A; Sebeni, M; Bordea, C; Viişoreanu, C; Bălănescu, I

    2000-01-01

    Mammographic screening and improvement of mammography resolution have resulted in the increasingly frequent identification of small-size mammary lesions that have no clinical expression. If in Western countries, approximately one quarter of breast cancers are discovered when clinically occult, in Romania such cases are rare and, most of the times, discovered merely by chance. Infraclinical mammary lesions identified by mammography pose problems concerning the appropriate response. The paper assesses the various diagnosis and therapy choices as well as the localization techniques to be employed in order to establish the best approach. We describe twelve cases of infraclinical mammary lesions identified by mammography. In two of this cases fine needle aspiration biopsy with cytological examination was used, and in one case we performed core biopsy and histological examination. In those cases, lesion localization has been performed using stereotactic X-ray devices. In nine cases, we performed excisional biopsy with histologic assessment. In four of those cases, the lesions proved to be malignant. Preoperative localization was performed with hookwires placed in the proximity of the lesion under mammographic control. In five of those cases, lesion coordinates have been determined by stereotaxy. Using this technique, we removed, in all cases, the clinical lesions identified by mammography. We believe surgical excision to be the best approach in such lesions. Total removal of the lesion enables a thorough histopathological examination resulting in more accurate diagnosis. Curative surgery is also possible within the same surgical procedure. Unless preoperative localization is performed the surgeon is in the position to excise an image that has no clinical expression. Under this circumstances surgical removal is performed blind, as the lesion is hard to be found even intraoperatory. Preoperative localization provides guidance to the surgeon, ensures removal of the lesion

  7. An essay on agriculture and population pressure.

    PubMed

    Macdonald, Andrew S

    2012-01-01

    This is an essay highlighting the fundamental importance of agriculture (historical and present) in the agro-socioeconomic evolution of human societies, from the times of the hunter/gatherers to the modern day. Attention is drawn in the text to the importance of deforestation in relation to micro and macro climate changes, and the vital role of carbon dioxide to plant and animal life. The essay also relates the world's natural resources to the present unsustainable population pressures.

  8. Two Essays in Financial Economics

    NASA Astrophysics Data System (ADS)

    Putnam, Kyle J.

    The following dissertation contains two distinct empirical essays which contribute to the overall field of Financial Economics. Chapter 1, entitled "The Determinants of Dynamic Dependence: An Analysis of Commodity Futures and Equity Markets," examines the determinants of the dynamic equity-commodity return correlations between five commodity futures sub-sectors (energy, foods and fibers, grains and oilseeds, livestock, and precious metals) and a value-weighted equity market index (S&P 500). The study utilizes the traditional DCC model, as well as three time-varying copulas: (i) the normal copula, (ii) the student's t copula, and (iii) the rotated-gumbel copula as dependence measures. Subsequently, the determinants of these various dependence measures are explored by analyzing several macroeconomic, financial, and speculation variables over different sample periods. Results indicate that the dynamic equity-commodity correlations for the energy, grains and oilseeds, precious metals, and to a lesser extent the foods and fibers, sub-sectors have become increasingly explainable by broad macroeconomic and financial market indicators, particularly after May 2003. Furthermore, these variables exhibit heterogeneous effects in terms of both magnitude and sign on each sub-sectors' equity-commodity correlation structure. Interestingly, the effects of increased financial market speculation are found to be extremely varied among the five sub-sectors. These results have important implications for portfolio selection, price formation, and risk management. Chapter 2, entitled, "US Community Bank Failure: An Empirical Investigation," examines the declining, but still pivotal role, of the US community banking industry. The study utilizes survival analysis to determine which accounting and macroeconomic variables help to predict community bank failure. Federal Deposit Insurance Corporation and Federal Reserve Bank data are utilized to compare 452 community banks which failed between

  9. Vascular anomalies: A pictorial review of nomenclature, diagnosis and treatment

    PubMed Central

    Nosher, John L; Murillo, Philip G; Liszewski, Mark; Gendel, Vyacheslav; Gribbin, Christopher E

    2014-01-01

    Vascular anomalies, including vascular malformations and tumors, are frequently straightforward to detect; however, accurate diagnosis and appropriate treatment are often challenging. Misdiagnosis of these lesions can lead clinicians in the wrong direction when treating these patients, which can have unfavorable results. This review presents an overview of the classification systems that have been developed for the diagnosis of vascular lesions with a focus on the imaging characteristics. Pictorial examples of each lesion on physical examination, as well as non-invasive and minimally invasive imaging are presented. An overview of the endovascular treatment of these lesions is also given. In some cases, vascular anomalies may be associated with an underlying syndrome and several of the most commonly encountered syndromes are discussed. Understanding of the classification systems, familiarity with the treatment options and knowledge of the associated syndromes are essential for all physicians working with this patient population. The approach to the described entities necessitates an organized multi-disciplinary team effort, with diagnostic imaging playing an increasingly important role in the proper diagnosis and a combined interventional radiologic and surgical treatment method showing promising results. PMID:25276311

  10. The origin of the β Pictoris stable gas

    NASA Astrophysics Data System (ADS)

    Lagrange, Anne-Marie; Maddison, Sarah; Augereau, Jean-Charles; Freudling, Wolfram; Lecavelier des Etangs, Alain; Dent, Bill

    2013-10-01

    The disk around the young star β Pictoris is the prototype of debris disks, whereby giant planets have already formed and terrestrial planet building is likely well underway. Multi-wavelength observations from optical to radio provide a detailed view of the dust component of the disk, but the gaseous component remains a mystery. Transient, highly redshifted absorptions lines are known to result from infalling cometary bodies, which may be perturbed by the giant planet we recently discovered orbiting 9 AU from the star. The most puzzling property of the β Pic system, however, is the origin of the stable gas present around the star. Initially seen only in absorption lines of ions and few neutrals, recent observations show emission of neutrals and CO. Our previous attempt to detect 21cm emission with ATCA (Freudling et al., 1995) provided an upper limit on the total HI mass, which has been widely used to constrain models of the gas evolution around β Pic. Our knowledge of the dust and gas disk has significantly evolved in recent years. Given ATCA's improved sensitivity, angular and spectral resolutions compared to our previous observations, we have a unique opportunity to detect HI and obtain information about its location within the disk. This will allow us, for the first time, to fully test if the icy grain scenario is responsible for the CO gas. We anticipate that our observations will have a major impact on the understanding of the β Pic system.

  11. Imaging of tuberous sclerosis complex: a pictorial review

    PubMed Central

    von Ranke, Felipe Mussi; Faria, Igor Murad; Zanetti, Gláucia; Hochhegger, Bruno; Souza Jr., Arthur Soares; Marchiori, Edson

    2017-01-01

    Tuberous sclerosis complex (TSC) is a genetically determined hamartomatous neurocutaneous disease with high phenotypic variability. TSC is characterized by widespread hamartomas and benign, or rarely malignant, neoplasms distributed in several organs throughout the body, especially in the brain, skin, retina, kidney, heart, and lung. Common manifestations include cortical tubers, subependymal nodules, white matter abnormalities, retinal abnormalities, cardiac rhabdomyoma, lymphangioleiomyomatosis, renal angiomyolipoma, and skin lesions. The wide range of organs affected by the disease implies that TSC1 and TSC2 genes play important roles in the regulation of cell proliferation and differentiation. Although recent advances in treatment have improved morbidity, the prognosis remains quite poor and nearly 40% of patients die by the age of 35 years. Imaging is important in the evaluation of TSC because of its role not only in presumptive diagnosis, but also in defining the full extent of involvement. This information allows a better understanding of the behavioural phenotype, as related to lesion location. Imaging also contributes to treatment planning. This pictorial review describes common and uncommon imaging manifestations of TSC. PMID:28298732

  12. Development of a stereo 3-D pictorial primary flight display

    NASA Technical Reports Server (NTRS)

    Nataupsky, Mark; Turner, Timothy L.; Lane, Harold; Crittenden, Lucille

    1989-01-01

    Computer-generated displays are becoming increasingly popular in aerospace applications. The use of stereo 3-D technology provides an opportunity to present depth perceptions which otherwise might be lacking. In addition, the third dimension could also be used as an additional dimension along which information can be encoded. Historically, the stereo 3-D displays have been used in entertainment, in experimental facilities, and in the handling of hazardous waste. In the last example, the source of the stereo images generally has been remotely controlled television camera pairs. The development of a stereo 3-D pictorial primary flight display used in a flight simulation environment is described. The applicability of stereo 3-D displays for aerospace crew stations to meet the anticipated needs for 2000 to 2020 time frame is investigated. Although, the actual equipment that could be used in an aerospace vehicle is not currently available, the lab research is necessary to determine where stereo 3-D enhances the display of information and how the displays should be formatted.

  13. Imaging of tuberous sclerosis complex: a pictorial review.

    PubMed

    von Ranke, Felipe Mussi; Faria, Igor Murad; Zanetti, Gláucia; Hochhegger, Bruno; Souza, Arthur Soares; Marchiori, Edson

    2017-01-01

    Tuberous sclerosis complex (TSC) is a genetically determined hamartomatous neurocutaneous disease with high phenotypic variability. TSC is characterized by widespread hamartomas and benign, or rarely malignant, neoplasms distributed in several organs throughout the body, especially in the brain, skin, retina, kidney, heart, and lung. Common manifestations include cortical tubers, subependymal nodules, white matter abnormalities, retinal abnormalities, cardiac rhabdomyoma, lymphangioleiomyomatosis, renal angiomyolipoma, and skin lesions. The wide range of organs affected by the disease implies that TSC1 and TSC2 genes play important roles in the regulation of cell proliferation and differentiation. Although recent advances in treatment have improved morbidity, the prognosis remains quite poor and nearly 40% of patients die by the age of 35 years. Imaging is important in the evaluation of TSC because of its role not only in presumptive diagnosis, but also in defining the full extent of involvement. This information allows a better understanding of the behavioural phenotype, as related to lesion location. Imaging also contributes to treatment planning. This pictorial review describes common and uncommon imaging manifestations of TSC.

  14. A pictorial review of signature patterns living in musculoskeletal ultrasonography

    PubMed Central

    Kim, Su Young; Cheon, Ji Hyun; Seo, Won Jun; Yang, Geun Young; Choi, Yun Mi

    2016-01-01

    The musculoskeletal system is mainly composed of the bones, muscles, tendons, and ligaments, in addition to nerves and blood vessels. The greatest difficulty in an ultrasonographic freeze-frame created by the examiner is recognition of the targeted structures without indicators, since an elephant's trunk may not be easily distinguished from its leg. It is not difficult to find descriptive ultrasonographic terms used for educational purposes, which help in distinguishing features of these structures either in a normal or abnormal anatomic condition. However, the terms sometimes create confusion when describing common objects, for example, in Western countries, pears have a triangular shape, but in Asia they are round. Skilled experts in musculoskeletal ultrasound have tried to express certain distinguishing features of anatomic landmarks using terms taken from everyday objects which may be reminiscent of that particular feature. This pictorial review introduces known signature patterns of distinguishing features in musculoskeletal ultrasound in a normal or abnormal condition, and may stir the beginners' interest to play a treasure-hunt game among unfamiliar images within a boundless ocean. PMID:27738500

  15. Mean glandular doses in mammography: a comparison of values displayed by a mammography unit with in-house values, both using the method proposed by Dance.

    PubMed

    Pasicz, Katarzyna; Fabiszewska, Ewa; Grabska, Iwona; Skrzyński, Witold

    2016-09-01

    The purpose of this work is to compare the mean glandular dose (MGD) displayed by the mammography system and the MGD calculated according to the method proposed by Dance for women. This study also attempts to analyse whether the relationship between the calculated and the displayed values is constant and what factors influence this relationship. Material for this study included data from 1200 exposures (i.e. six series; each series consisting of 200 exposures) performed with one full-field digital mammography unit. Based on collected parameters of exposures, values of the MGD for individual mammography examinations were calculated according to the methods proposed by Dance. Obtained values of the MGD were compared with the values displayed by the mammography system. The MGD displayed by the mammography system and the MGD calculated according to the method proposed by Dance for women are significantly different. This result emphasises the importance of verifying MGD values for patient radiation protection, particularly after machine servicing.

  16. Essays on incomplete contracts in regulatory activities

    NASA Astrophysics Data System (ADS)

    Saavedra, Eduardo Humberto

    This dissertation consists of three essays. The first essay, The Hold-Up Problem in Public Infrastructure Franchising, characterizes the equilibria of the investment decisions in public infrastructure franchising under incomplete contracting and ex-post renegotiation. The parties (government and a firm) are unable to credibly commit to the contracted investment plan, so that a second step investment is renegotiated by the parties at the revision stage. As expected, the possibility of renegotiation affects initial non-verifiable investments. The main conclusion of this essay is that not only underinvestment but also overinvestment in infrastructure may arise in equilibrium, compared to the complete contracting case. The second essay, Alternative Institutional Arrangements in Network Utilities: An Incomplete Contracting Approach, presents a theoretical assessment of the efficiency implications of privatizing natural monopolies which are vertically related to potential competitive firms. Based on the incomplete contracts and asymmetric information paradigm. I develop a model that analyzes the relative advantages of different institutional arrangements---alternative ownership and market structures in the industry--- in terms of their allocative and productive efficiencies. The main policy conclusion of this essay is that both ownership and the existence of conglomerates in network industries matter. Among other conclusions, this essay provides an economic rationale for a mixed economy in which the network is public and vertical separation of the industry when the natural monopoly is under private ownership. The last essay, Opportunistic Behavior and Legal Disputes in the Chilean Electricity Sector, analyzes post-contractual disputes in this newly privatized industry. It discusses the presumption that opportunistic behavior and disputes arise due to inadequate market design, ambiguous regulation, and institutional weaknesses. This chapter also assesses the presumption

  17. Experience with a proposed teleradiology system for digital mammography

    NASA Astrophysics Data System (ADS)

    Saulnier, Emilie T.; Mitchell, Robert J.; Abdel-Malek, Aiman A.; Dudding, Kathryn E.

    1995-05-01

    Teleradiology offers significant improvement in efficiency and effectiveness over current practices in traditional film/screen-based diagnosis. In the context of digital mammography, the increasing number of women who need to be screened for breast cancer, including those in remote rural regions, make the advantages of teleradiology especially attractive for digital mammography. At the same time, the size and resolution of digital mammograms are among the most challenging to support in a cost effective teleradiology system. This paper describes a teleradiology architecture developed for use with digital mammography by GE Corporate Research and Development in collaboration with Massachusetts General Hospital under National Cancer Institute (NCI/NIH) grant number R01 CA60246-01. Experience with a testbed prototype is described. The telemammography architecture is intended to consist of a main mammography diagnostic site serving several remote screening sites. As patient exams become available, they are forwarded by an image server to the diagnostic site over a WAN communications link. A radiologist at the diagnostic site views a patient exam as it arrives, interprets it, and then relays a report back to the technician at the remote site. A secondary future scenario consists of mobile units which forward images to a remote site, which then forwards them to the main diagnostic site. The testbed architecture is based on the Digital Imaging and Communications in Medicine (DICOM) standard, created by the American College of Radiology (ACR) and National Electrical Manufacturers Association (NEMA). A specification of vendor-independent data formats and data transfer services for digital medical images, DICOM specifies a protocol suite starting at the application layer downward, including the TCP/IP layers. The current DICOM definition does not provide an information element that is specifically tailored to mammography, so we have used the DICOM secondary capture data format

  18. Filtering Essays by Means of a Software Tool: Identifying Poor Essays

    ERIC Educational Resources Information Center

    Seifried, Eva; Lenhard, Wolfgang; Spinath, Birgit

    2017-01-01

    Writing essays and receiving feedback can be useful for fostering students' learning and motivation. When faced with large class sizes, it is desirable to identify students who might particularly benefit from feedback. In this article, we tested the potential of Latent Semantic Analysis (LSA) for identifying poor essays. A total of 14 teaching…

  19. Essays on Macroeconomics and Oil

    NASA Astrophysics Data System (ADS)

    Cakir, Nida

    In these essays, I examine (i) the empirical methods that are widely used in the literature to measure total factor productivity growth and (ii) the impact of nationalization on productivity in the oil industry. The first chapter, which is an ongoing work with SHI, Wei, investigates two empirical measures, quantity-based (primal) measure and price-based (dual) measure, of total factor productivity growth. My co-author and I analyze how these two measures are affected by output market imperfection or variable capacity utilization. We find that under constant-returns-to-scale production function assumption, existence of the imperfect competition in the output market creates a gap between the measured TFP growth and the true TFP growth, no matter which method is used. However, theoretically, it does not affect the equivalence between the two measures. Under variable capacity utilization, we show that constant-returns-to-scale assumption is almost enough to guarantee the validity of the two methods in correctly capturing the true TFP growth. In the second and third chapters, I analyze the link between nationalization and productivity. The second chapter documents the trends in expropriation acts, and evaluates the impact of expropriations on labor productivity of resource-rich developing countries in the oil industry. In the first part of this chapter, I investigate the trends in the expropriation acts that took place in 102 developing countries during the period 1922-2006. I find that more than half of the acts occurred between 1970 and 1976, there has been an increase in the number of expropriations in recent years, and the extractive sector including petroleum is more likely to be expropriated. Motivated by these facts, in the second part, I examine the oil industry in a period of widespread expropriations, the 1970s. In a sample of major oil-producing countries including OPEC and non-OPEC members, I show that losses in relative labor productivity after

  20. Three essays on auction markets

    NASA Astrophysics Data System (ADS)

    Shunda, Nicholas James

    This dissertation contains a series of theoretical investigations of auction markets. The essays it contains cover wholesale electricity markets, a popular selling mechanism on eBay, and supplier entry into multi-unit procurement auctions. The study in Chapter 1 compares the procurement cost-minimizing and productive efficiency performance of the auction mechanism used by independent system operators in wholesale electricity auction markets in the U.S. with that of a proposed alternative. The current practice allocates energy contracts as if the auction featured a discriminatory final payment method when, in fact, the markets are uniform price auctions. The proposed alternative explicitly accounts for the market-clearing price during the allocation phase. We find that the proposed alternative largely outperforms the current practice on the basis of procurement costs in the context of simple auction markets featuring both day-ahead and real-time auctions and that the procurement cost advantage of the alternative is complete when we simulate the effects of increased competition. We also find that a tradeoff between the objectives of procurement cost minimization and productive efficiency emerges in our simple auction markets and persists in the face of increased competition. The study in Chapter 2 considers a possible rationale for an auction with a buy price. In an auction with a buy price, the seller provides bidders with an option to end the auction early by accepting a transaction at a posted price. The "Buy-It-Now" option on eBay is a leading example of an auction with a buy price. The study develops a model of an auction with a buy price in which bidders use the auction's reserve price and buy price to formulate a reference price. The model both explains why a revenue-maximizing seller would want to augment her auction with a buy price and demonstrates that the seller sets a higher reserve price when she can affect the bidders' reference price through the

  1. Young Children's Knowledge of the Representational Function of Pictorial Symbols: Development across the Preschool Years in Three Cultures

    ERIC Educational Resources Information Center

    Callaghan, Tara C.; Rochat, Philippe; Corbit, John

    2012-01-01

    Three- to 5-year-old children's knowledge that pictures have a representational function for others was investigated using a pictorial false-belief task. In Study 1, children passed the task at around 4 years old, and performance was correlated with standard false-belief and pictorial symbol tasks. In Study 2, the performance of children from two…

  2. Technology-Aided Pictorial Cues to Support the Performance of Daily Activities by Persons with Moderate Alzheimer's Disease

    ERIC Educational Resources Information Center

    Lancioni, Giulio E.; Perilli, Viviana; Singh, Nirbhay N.; O'Reilly, Mark F.; Sigafoos, Jeff; Cassano, Germana; Pinto, Katia; Minervini, Mauro G.; Oliva, Doretta

    2012-01-01

    We developed a technology-aided intervention strategy relying on pictorial cues alone or in combination with verbal instructions and assessed these two versions of the strategy with three persons with moderate Alzheimer's disease. In Section I of the study, the strategy version with pictorial cues plus verbal instructions was compared with an…

  3. Three essays in energy and environmental economics

    NASA Astrophysics Data System (ADS)

    Redlinger, Michael

    This thesis exploits the boom in U.S. oil and gas production to explore several empirical questions in environmental and energy economics. In the first essay, statistical techniques are employed to evaluate learning-by-doing in the Bakken Shale Play. Furthermore, the essay demonstrates organizational forgetting and knowledge spillovers among firms. The results show rates of learning in an important sector the U.S. economy and may have broader lessons for productivity gains and losses. The second essay investigates interfirm learning economies in oil well drilling in terms of productivity improvements and increases in environmental safety. The empirical results improve our understanding of how interfirm relationships influence productivity as well as the drivers of environmental incidents. Lastly, the third essay analyzes the impacts of stricter environmental regulations on oil production and well drilling in North Dakota. The results have particular relevance for policymakers seeking to understand the trade-offs between resource development and environmental quality. These three essays ultimately expand our knowledge of how learning economies occur and the effects of environmental regulations on economic activity.

  4. Mammography: an update of the EUSOBI recommendations on information for women.

    PubMed

    Sardanelli, Francesco; Fallenberg, Eva M; Clauser, Paola; Trimboli, Rubina M; Camps-Herrero, Julia; Helbich, Thomas H; Forrai, Gabor

    2017-02-01

    This article summarises the information to be offered to women about mammography. After a delineation of the aim of early diagnosis of breast cancer, the difference between screening mammography and diagnostic mammography is explained. The need to bring images and reports from the previous mammogram (and from other recent breast imaging examinations) is highlighted. Mammography technique and procedure are described with particular attention to discomfort and pain experienced by a small number of women who undergo the test. Information is given on the recall during a screening programme and on the request for further work-up after a diagnostic mammography. The logic of the mammography report and of classification systems such as R1-R5 and BI-RADS is illustrated, and brief but clear information is given about the diagnostic performance of the test, with particular reference to interval cancers, i.e., those cancers that are missed at screening mammography. Moreover, the breast cancer risk due to radiation exposure from mammography is compared to the reduction in mortality obtained with the test, and the concept of overdiagnosis is presented with a reliable estimation of its extent. Information about new mammographic technologies (tomosynthesis and contrast-enhanced spectral mammography) is also given. Finally, frequently asked questions are answered.

  5. Mammography X-Ray Spectra Simulated with Monte Carlo

    SciTech Connect

    Vega-Carrillo, H. R.; Gonzalez, J. Ramirez; Manzanares-Acuna, E.; Hernandez-Davila, V. M.; Villasana, R. Hernandez; Mercado, G. A.

    2008-08-11

    Monte Carlo calculations have been carried out to obtain the x-ray spectra of various target-filter combinations for a mammography unit. Mammography is widely used to diagnose breast cancer. Further to Mo target with Mo filter combination, Rh/Rh, Mo/Rh, Mo/Al, Rh/Al, and W/Rh are also utilized. In this work Monte Carlo calculations, using MCNP 4C code, were carried out to estimate the x-ray spectra produced when a beam of 28 keV electrons did collide with Mo, Rh and W targets. Resulting x-ray spectra show characteristic x-rays and continuous bremsstrahlung. Spectra were also calculated including filters.

  6. LATIN AMERICAN IMAGE QUALITY SURVEY IN DIGITAL MAMMOGRAPHY STUDIES.

    PubMed

    Mora, Patricia; Khoury, Helen; Bitelli, Regina; Quintero, Ana Rosa; Garay, Fernando; Aguilar, Juan García; Gamarra, Mirtha; Ubeda, Carlos

    2016-03-23

    Under International Atomic Energy Agency regional programmeTSA3 Radiological Protection of Patients in Medical Exposures, Latin American countries evaluated the image quality and glandular doses for digital mammography equipment with the purpose of seeing the performance and compliance with international recommendations. Totally, 24 institutions participated from Brazil, Chile, Costa Rica, El Salvador, Mexico, Paraguay and Venezuela. Signal difference noise ratio results showed for CR poor compliance with tolerances; better results were obtained for full-field digital mammography equipment. Mean glandular dose results showed that the majority of units have values below the acceptable dose levels. This joint Latin American project identified common problems: difficulty in working with digital images and lack of specific training by medical physicists from the region. Image quality is a main issue not being satisfied in accordance with international recommendations; optimisation processes in which the doses are increased should be very carefully done in order to improve early detection of any cancer signs.

  7. An SVM Based Approach for the Analysis Of Mammography Images

    NASA Astrophysics Data System (ADS)

    Gan, X.; Kapsokalivas, L.; Skaliotis, A.; Steinhöfel, K.; Tangaro, S.

    2007-09-01

    Mammography is among the most popular imaging techniques used in the diagnosis of breast cancer. Nevertheless distinguishing between healthy and ill images is hard even for an experienced radiologist, because a single image usually includes several regions of interest (ROIs). The hardness of this classification problem along with the substantial amount of data, gathered from patients' medical history, motivates the use of a machine learning approach as part of a CAD (Computer Aided Detection) tool, aiming to assist radiologists in the characterization of mammography images. Specifically, our approach involves: i) the ROI extraction, ii) the Feature Vector extraction, iii) the Support Vector Machine (SVM) classification of ROIs and iv) the characterization of the whole image. We evaluate the performance of our approach in terms of the SVM's training and testing error and in terms of ROI specificity—sensitivity. The results show a relation between the number of features used and the SVM's performance.

  8. A comparison of the performance of digital mammography systems.

    PubMed

    Monnin, P; Gutierrez, D; Bulling, S; Guntern, D; Verdun, F R

    2007-03-01

    An objective analysis of image quality parameters was performed for six digital mammography systems. The presampled modulation transfer function (MTF), normalized noise power spectrum (NNPS), and detective quantum efficiency (DQE) for the systems were determined at different doses, for 28 kVp with a Mo/Mo or W/Al target/filter combination and 2 mm of additional aluminium filtration. The flat-panel units have higher MTF and DQE in the mid to high frequency range than standard CR systems. The highest DQE, over the whole dose range, is for the slit-scanning direct photon counting system. Dual-side read CR can overcome the inherent x-ray absorption and signal collection limitations of standard CR mammography, improving the low-frequency DQE by 40%, to the same level as full-field systems, but it does not improve the poor spatial resolution of phosphor.

  9. A comparison of the performance of digital mammography systems

    SciTech Connect

    Monnin, P.; Gutierrez, D.; Bulling, S.; Guntern, D.; Verdun, F. R.

    2007-03-15

    An objective analysis of image quality parameters was performed for six digital mammography systems. The presampled modulation transfer function (MTF), normalized noise power spectrum (NNPS), and detective quantum efficiency (DQE) for the systems were determined at different doses, for 28 kVp with a Mo/Mo or W/Al target/filter combination and 2 mm of additional aluminium filtration. The flat-panel units have higher MTF and DQE in the mid to high frequency range than standard CR systems. The highest DQE, over the whole dose range, is for the slit-scanning direct photon counting system. Dual-side read CR can overcome the inherent x-ray absorption and signal collection limitations of standard CR mammography, improving the low-frequency DQE by 40%, to the same level as full-field systems, but it does not improve the poor spatial resolution of phosphor.

  10. Nonlinear Elasto-Mammography for Characterization of Breast Tissue Properties

    PubMed Central

    Wang, Z. G.; Liu, Y.; Wang, G.; Sun, L. Z.

    2011-01-01

    Quantification of the mechanical behavior of normal and cancerous tissues has important implication in the diagnosis of breast tumor. The present work extends the authors' nonlinear elastography framework to incorporate the conventional X-ray mammography, where the projection of displacement information is acquired instead of full three-dimensional (3D) vector. The elastic parameters of normal and cancerous breast tissues are identified by minimizing the difference between the measurement and the corresponding computational prediction. An adjoint method is derived to calculate the gradient of the objective function. Simulations are conducted on a 3D breast phantom consisting of the fatty tissue, glandular tissue, and cancerous tumor, whose mechanical responses are hyperelastic in nature. The material parameters are identified with consideration of measurement error. The results demonstrate that the projective displacements acquired in X-ray mammography provide sufficient constitutive information of the tumor and prove the usability and robustness of the proposed method and algorithm. PMID:22235197

  11. Lithium Depletion in the Beta Pictoris Moving Group

    NASA Astrophysics Data System (ADS)

    Yee, Jennifer C.; Jensen, E. L.; Reaser, B. E.

    2006-12-01

    We present a study of lithium depletion in twelve late-type pre-main-sequence stars in the coeval Beta Pictoris Moving Group (BPMG). The age of this group ( 12 Myr) is well constrained because all of the stars in the sample have Hipparcos distances. We have determined Li abundances for these K and M stars using equivalent width measurements of the 6707.8 Angstrom Li I line from new high-resolution, high-S/N echelle spectra, and we compare these abundances to models of pre-main-sequence Li depletion by Baraffe et al. (1998), D'Antona & Mazzitelli (1997, 1998), and Siess, Dufour, & Forestini (2000). Significantly more lithium depletion is observed in the sample than is predicted for a group of this age. In particular, the discrepancy between the predicted and the observed lithium abundances increases with decreasing effective temperature, suggesting a problem with theories describing pre-main-sequence lithium depletion. Our data indicate that M stars deplete lithium more rapidly than predicted, which could make M-type post-T-Tauri stars difficult to identify. In addition, we compare our results to the work of Song, Bessell, & Zuckerman (2002) on HIP 112312. In contrast to that work, we did not observe the lithium depletion boundary of the BPMG; none of the three M4.5 stars in the sample showed evidence of lithium (log N(Li) < -0.5), indicating a lithium depletion boundary later than M4.5, further underscoring the gap between age estimates from lithium depletion and those from theoretical evolutionary tracks. We gratefully acknowledge the support of the National Science Foundation through grant AST-0307830.

  12. PI-RADS Version 2: A Pictorial Update.

    PubMed

    Purysko, Andrei S; Rosenkrantz, Andrew B; Barentsz, Jelle O; Weinreb, Jeffrey C; Macura, Katarzyna J

    2016-01-01

    The Prostate Imaging Reporting and Data System (PI-RADS) is the result of an extensive international collaborative effort. PI-RADS provides a comprehensive yet practical set of guidelines for the interpretation and reporting of prostate multiparametric magnetic resonance (MR) imaging that will promote the use of this modality for detecting clinically significant prostate cancer. The revised PI-RADS version (PI-RADS version 2) introduces important changes to the original system used for assessing the level of suspicion for clinically significant cancer with multiparametric MR imaging. For peripheral zone abnormalities in PI-RADS version 2, the score obtained from the apparent diffusion coefficient (ADC) map in combination with diffusion-weighted imaging (DWI) performed with high b values (≥1400 sec/mm(2)) is the dominant parameter for determining the overall level of suspicion for clinically significant cancer. For transition zone abnormalities, the score obtained from T2-weighted MR imaging is dominant for overall lesion assessment. Dynamic contrast material-enhanced MR imaging has ancillary roles in the characterization of peripheral zone lesions considered equivocal for clinically significant cancer on the basis of the DWI-ADC combination and in the detection of lesions missed with other multiparametric MR pulse sequences. Assessment with dynamic contrast-enhanced MR imaging is also simplified, being considered positive or negative on the basis of qualitative evaluation for a focal area of rapid enhancement matching an abnormality on DWI-ADC or T2-weighted MR images. In PI-RADS version 2, MR spectroscopic imaging is not incorporated into lesion assessment. In this article, a pictorial overview is provided of the revised PI-RADS version 2 assessment categories for the likelihood of clinically significant cancer. PI-RADS version 2 is expected to evolve with time, with updated versions being released as experience in the use of PI-RADS version 2 increases and as

  13. Image and Dose Simulation in Support of New Mammography Modalities

    SciTech Connect

    Kuruvilla Verghese

    2002-04-05

    This report summarizes the highlights of the research performed under the 2-year NEER grant from the Department of Energy. The primary outcome of the work was a new Monte Carlo code, MCMIS-DS, for Monte Carlo for Mammography Image Simulation including Differential Sampling. The code was written to generate simulated images and dose distributions from two different new digital x-ray imaging modalities, namely, synchrotron imaging (SI) and a slot geometry digital mammography system called Fisher Senoscan. A differential sampling scheme was added to the code to generate multiple images that included variations in the parameters of the measurement system and the object in a single execution of the code. The code is to serve multiple purposes; (1) to answer questions regarding the contribution of scattered photons to images, (2) for use in design optimization studies, and (3) to do up to second-order perturbation studies to assess the effects of design parameter variations and/or physical parameters of the object (the breast) without having to re-run the code for each set of varied parameters. The accuracy and fidelity of the code were validated by a large variety of benchmark studies using published data and also using experimental results from mammography phantoms on both imaging modalities.

  14. Phase mammography - a new technique for breast investigation

    NASA Astrophysics Data System (ADS)

    Ingal, Viktor N.; Beliaevskaya, Elena A.; Brianskaya, Alla P.; Merkurieva, Raisa D.

    1998-09-01

    A new phase radiography technique for investigation and diagnosis of neoplasms in breast tissue is proposed. Forty-four mammography samples with adenocarcinoma that had been prepared after mastectomy were tested in a new phase radiography device. It was shown that the phase images manifest the changes in parenchyma structure due to malignancy and microcalcifications up to in size. Results obtained were verified by histological examination. A contrast of the phase images of small microcalcifications and distortions of the stroma architecture ranges up to 40-60%; spatial resolution is about . The proposed technique offers outstanding possibilities for digital mammography. The small and large details of structure manifest themselves with practically the same contrast. Phase images differ from those obtained in mammography and many details still require further decoding.

  15. A task-based quality control metric for digital mammography

    NASA Astrophysics Data System (ADS)

    Maki Bloomquist, A. K.; Mainprize, J. G.; Mawdsley, G. E.; Yaffe, M. J.

    2014-11-01

    A reader study was conducted to tune the parameters of an observer model used to predict the detectability index (dʹ ) of test objects as a task-based quality control (QC) metric for digital mammography. A simple test phantom was imaged to measure the model parameters, namely, noise power spectrum, modulation transfer function and test-object contrast. These are then used in a non-prewhitening observer model, incorporating an eye-filter and internal noise, to predict dʹ. The model was tuned by measuring dʹ of discs in a four-alternative forced choice reader study. For each disc diameter, dʹ was used to estimate the threshold thicknesses for detectability. Data were obtained for six types of digital mammography systems using varying detector technologies and x-ray spectra. A strong correlation was found between measured and modeled values of dʹ, with Pearson correlation coefficient of 0.96. Repeated measurements from separate images of the test phantom show an average coefficient of variation in dʹ for different systems between 0.07 and 0.10. Standard deviations in the threshold thickness ranged between 0.001 and 0.017 mm. The model is robust and the results are relatively system independent, suggesting that observer model dʹ shows promise as a cross platform QC metric for digital mammography.

  16. Characteristics of YouTube™ Videos Related to Mammography.

    PubMed

    Basch, Corey H; Hillyer, Grace Clarke; MacDonald, Zerlina L; Reeves, Rachel; Basch, Charles E

    2015-12-01

    With a monthly total of more than one billion unique visitors, YouTube™ is one of the Internet's most visited websites and contributes to the growing amount of health-related information on the Internet. The purpose of this study was to analyze coverage of mammography screening in popular YouTube™ videos. A total of 173 videos were included in the analysis. Compared with professionally created videos, consumer-created videos had a significantly greater number of comments (>9 comments 38.0% for consumer vs. 11.8% for professional videos, p=<0.001). Videos created by professionals more often portrayed general mammography information (97.1 vs. 88.7%) compared to those created by consumers. The vast majority of videos presented general information (93.6%) related to mammography, and almost two thirds addressed preparing for the test. Less than 20% dealt with other types of examinations. Approximately 30% discussed pain associated with the examination (35.3%) and addressed issues of anxiety (32.4%) and fear (29.5%). Nearly half of the videos presented information about the test results (46.2%). Over 25% covered medical or family history. The majority did not pertain to a specific age group. Future research should focus on analyzing the accuracy of the information in the videos.

  17. Hidden costs of mobile mammography: is subsidization necessary?

    PubMed

    Wolk, R B

    1992-06-01

    Two major impediments to an effective mammography program are inaccessibility and cost. This article itemizes the expenses associated with providing a mobile screening program accredited by the American College of Radiology (ACR) during a 3-year period. Mobile Diagnostics Inc. established a mobile mammography service in April 1987. A 36-ft (11-m) van is staffed by two registered technologists. The unit includes on-board processing and educational videotapes. Analysis of expenses for the years 1988, 1989, and 1990 does not include interpretation fees. A total of 3522 patients were examined in 1988, 4232 in 1989, and 5005 in 1990. Fixed operating expenses in 1988 were $70/examination and variable expenses were $13/examination, resulting in an average total cost per examination of $83. Fixed costs in 1989 were $63, variable costs were $15, and total costs were $78 per examination. Fixed costs in 1990 were $55, variable costs were $14, and total costs were $69 per examination. Many third parties, including Medicare, are contemplating a global screening fee in the $50-$60 range. An average payment of $55 would require examination of more than 6500 patients a year or 28 patients a day to break even. Our experience suggests that some form of subsidization may be necessary to sustain a mobile mammography service at those reimbursement levels.

  18. Behavioral Constructs and Mammography in Five Ethnic Groups

    PubMed Central

    Stewart, Susan L.; Rakowski, William; Pasick, Rena J.

    2010-01-01

    Intention, self-efficacy, perceived susceptibility, perceived benefits, and subjective norms are key constructs of health behavior theories; their predictive validity for cancer screening has not been ascertained in multiethnic populations. Participants were 1,463 African American, Chinese, Filipina, Latina, and White women aged 40 to 74 interviewed by telephone in their preferred languages. The relationship between base-line constructs and mammography 2 years later was assessed using multivariable logistic regression. Intention predicted mammography overall and among Whites (odds ratio [OR] = 5.0, 95% confidence interval [CI] = 2.4, 10), with racial/ethnic differences in association (p = .020). Self-efficacy predicted mammography overall and among Whites (OR = 3.5, 95% CI = 1.1, 11), with no racial/ethnic interaction. Perceived benefits and subjective norms were associated with screening overall and in some racial/ethnic groups. These results generally support cross-cultural applicability of four of the five constructs to screening with mixed predictive value of measures across racial/ethnic groups. Additional in-depth inquiry is required to refine assessment of constructs. PMID:19805790

  19. Sensitivity of Self-report Mammography Use in Older Women

    PubMed Central

    Craig, Benjamin M.; Quinn, Gwendolyn P.; Vadaparampil, Susan T.

    2013-01-01

    Background Recent survey evidence indicates a decline in mammography use among older women. The objective of this study was to detect sensitivity variation in self-reported mammography use and pose evidence-based suggestions to increase survey accuracy. Methods Using 1991-2006 Medicare Current Beneficiary Survey (MCBS), 15,357 women, age 65 or older, were selected based on use of mammography services. The women were interviewed in the community setting at random periods after screening and asked, “Have you had a mammogram or breast x-ray since [today's date] one year ago?” Statistical analyses were conducted between March 11 and April 28 of 2008. This study tested whether sensitivity (i.e., probability of an affirmative response) was dependent on length of the recall period and on respondent demographic and socioeconomic characteristics. Results Overall, 90.4% of the older women self-reported use; however, sensitivity decreased as the recall period lengthened (90% at 6 months, 80% at 12 months). This time effect was significantly higher among older, economically disadvantaged women. Sensitivity also decreased an additional 13.8% if the event occurred in the previous calendar year, and 3.5% if conducted in a non-English language or by proxy. Conclusion Greatest sensitivity use occurred during the 6-month period after service without straddling calendar years. These findings may aid the tailoring of future surveys for older adults, improving the recall of preventive services. PMID:19840700

  20. Theoretical analysis of high-resolution digital mammography

    NASA Astrophysics Data System (ADS)

    Suryanarayanan, Sankararaman; Karellas, Andrew; Vedantham, Srinivasan; Sechopoulos, Ioannis

    2006-06-01

    The performance of a high-resolution charge coupled device-based full-field digital mammography imager was analysed using a mathematical framework based on an adaptation of cascaded linear systems theory described by other investigators. This work has been conducted in order to understand the impact of various design parameters on the physical performance characteristics of the imager. Specifically, the effect of pixel size, scintillator thickness and packing density, x-ray spectra, air kerma, dark current, charge integration time, and pixel fill-factor on the frequency dependent detective quantum efficiency was studied using a charge-coupled device as a reference platform. The imaging system was modelled as a series of physical processes with gain and spatial spreading. For each stage, the signal and noise power spectra were computed and propagated through the imaging chain as inputs to subsequent stages. Good agreement between experimental and theoretical predictions was obtained for various x-ray spectral conditions that were investigated. The modulation transfer function, MTF(f) and detective quantum efficiency DQE(f) characteristics obtained in this study are encouraging and comparable to other digital mammography systems. The results of this study strongly suggest the feasibility of large area scintillator-based digital mammography imagers with pixel sizes below 100 µm.

  1. The influence of software filtering in digital mammography image quality

    NASA Astrophysics Data System (ADS)

    Michail, C.; Spyropoulou, V.; Kalyvas, N.; Valais, I.; Dimitropoulos, N.; Fountos, G.; Kandarakis, I.; Panayiotakis, G.

    2009-05-01

    Breast cancer is one of the most frequently diagnosed cancers among women. Several techniques have been developed to help in the early detection of breast cancer such as conventional and digital x-ray mammography, positron and single-photon emission mammography, etc. A key advantage in digital mammography is that images can be manipulated as simple computer image files. Thus non-dedicated commercially available image manipulation software can be employed to process and store the images. The image processing tools of the Photoshop (CS 2) software usually incorporate digital filters which may be used to reduce image noise, enhance contrast and increase spatial resolution. However, improving an image quality parameter may result in degradation of another. The aim of this work was to investigate the influence of three sharpening filters, named hereafter sharpen, sharpen more and sharpen edges on image resolution and noise. Image resolution was assessed by means of the Modulation Transfer Function (MTF).In conclusion it was found that the correct use of commercial non-dedicated software on digital mammograms may improve some aspects of image quality.

  2. Essays on refining markets and environmental policy

    NASA Astrophysics Data System (ADS)

    Oladunjoye, Olusegun Akintunde

    This thesis is comprised of three essays. The first two essays examine empirically the relationship between crude oil price and wholesale gasoline prices in the U.S. petroleum refining industry while the third essay determines the optimal combination of emissions tax and environmental research and development (ER&D) subsidy when firms organize ER&D either competitively or as a research joint venture (RJV). In the first essay, we estimate an error correction model to determine the effects of market structure on the speed of adjustment of wholesale gasoline prices, to crude oil price changes. The results indicate that market structure does not have a strong effect on the dynamics of price adjustment in the three regional markets examined. In the second essay, we allow for inventories to affect the relationship between crude oil and wholesale gasoline prices by allowing them to affect the probability of regime change in a Markov-switching model of the refining margin. We find that low gasoline inventory increases the probability of switching from the low margin regime to the high margin regime and also increases the probability of staying in the high margin regime. This is consistent with the predictions of the competitive storage theory. In the third essay, we extend the Industrial Organization R&D theory to the determination of optimal environmental policies. We find that RJV is socially desirable. In comparison to competitive ER&D, we suggest that regulators should encourage RJV with a lower emissions tax and higher subsidy as these will lead to the coordination of ER&D activities and eliminate duplication of efforts while firms internalize their technological spillover externality.

  3. On the Power of Fine Arts Pictorial Imagery in Science Education

    NASA Astrophysics Data System (ADS)

    Galili, Igal

    2013-08-01

    The paper describes and illustrates the potential of using pictorial artistic images in supporting teaching scientific concepts and the nature of science. In the first part, the case of Giotto's fresco of stigmatization of St. Francis is described within the interpretation of relationship between the figures as between an object and its mirror image. Educational implications of this case study are suggested. The second part presents several pictorial images that can be used in classroom teaching of science for facilitation of hermeneutic discussion in science classes addressing the nature of scientific knowledge changed in the course of history.

  4. Blue Marble Space Institute essay contest

    NASA Astrophysics Data System (ADS)

    Wendel, JoAnna

    2014-04-01

    The Blue Marble Space Institute of Science, based in Seattle, Wash., is inviting college students to participate in its essay contest. Essays need to address the question, "In the next 100 years, how can human civilization prepare for the long-term changes to the Earth system that will occur over the coming millennium?" According to the institute, the purpose of the contest is "to stimulate creative thinking relating to space exploration and global issues by exploring how changes in the Earth system will affect humanity's future."

  5. Preliminary results for positron emission mammography: real-time functional breast imaging in a conventional mammography gantry.

    PubMed

    Weinberg, I; Majewski, S; Weisenberger, A; Markowitz, A; Aloj, L; Majewski, L; Danforth, D; Mulshine, J; Cowan, K; Zujewski, J; Chow, C; Jones, E; Chang, V; Berg, W; Frank, J

    1996-07-01

    In order to optimally integrate radiotracer breast imaging within the breast clinic, anatomy and pathology should be easily correlated with functional nuclear medicine breast images. As a first step in the development of a hybrid functional/anatomic breast imaging platform with biopsy capability, a conventional X-ray mammography gantry was modified to image the compressed breast with positron emitters. Phantom studies with the positron emission mammography (PEM) device showed that a 1-cc hot spot could be detected within 5 min. A preliminary clinical trial demonstrated in vivo visualization of primary breast cancer within 4 min. For sites where positron-emitting radionuclides are available, PEM promises to achieve low-cost directed functional examination of breast abnormalities, with the potential for achieving X-ray correlation and image-guided biopsy.

  6. Near monochromatic X-rays for digital slot-scan mammography: initial findings.

    PubMed

    Diekmann, Felix; Diekmann, S; Richter, K; Bick, U; Fischer, T; Lawaczeck, R; Press, W-R; Schön, K; Weinmann, H-J; Arkadiev, V; Bjeoumikhov, A; Langhoff, N; Rabe, J; Roth, P; Tilgner, J; Wedell, R; Krumrey, M; Linke, U; Ulm, G; Hamm, B

    2004-09-01

    X-ray spectra are composed of a broad bremsspectrum and anode-characteristic emission lines. In mammography typically molybdenum (Mo), rhodium (Rh) or tungsten (W) anodes are used in combination with Mo, Rh or aluminium filters. Only the photons with energies between 17 and 22 keV of the resulting spectrum are suitable for the soft tissue imaging needed for mammography. The aim of this article is to present first results obtained with a monochromator module mounted at the exit of the X-ray tube of a conventional clinical mammography unit. The experimental setup consists of a Siemens Mammomat 300, an X-ray monochromator module and a linear array detector for image acquisition. The technique is similar to the slot-scan technique known from digital mammography. The experimental machine allows to obtain images both with polychromatic and monochromatic X-rays. Initial evaluation of the system was performed by examination of a contrast-detail phantom (CD-MAM-phantom, Nijmegen, The Netherlands). Images done with the new monochromatic technique were compared to images of the phantom done with polychromatic spectra, with film-screen mammography as well as with digital mammography. The new technique with monochromatic slot-scan mammography resulted in correct identification of 93% of the phantom. Digital slot-scan mammography with polychromatic beam resulted in correct identification of 87%, digital full-field mammography in 83% and conventional film-screen mammography in 70% of the phantom. The results suggest that monochromatization has a potential for improving image quality or decreasing dose in X-ray mammography.

  7. Psychosocial determinants of mammography follow-up after receipt of abnormal mammography results in medically underserved women.

    PubMed

    Fair, Alecia Malin; Wujcik, Debra; Lin, Jin-Mann Sally; Zheng, Wei; Egan, Kathleen M; Grau, Ana M; Champion, Victoria L; Wallston, Kenneth A

    2010-02-01

    This article targets the relationship between psychosocial determinants and abnormal screening mammography follow-up in a medically underserved population. Health belief scales were modified to refer to diagnostic follow-up versus annual screening. A retrospective cohort study design was used. Statistical analyses were performed examining relationships among sociodemographic factors, psychosocial determinants, and abnormal mammography follow-up. Women with lower mean internal health locus of control scores (3.14) were two times more likely than women with higher mean internal health locus of control scores (3.98) to have inadequate follow-up (OR=2.53, 95% CI=1.12-5.36). Women with less than a high school education had lower cancer fatalism scores than women who had completed high school (47.5 vs. 55.2, p-value=.02) and lower mean external health locus of control scores (3.0 vs. 5.3) (p-value<.01). These constructs have implications for understanding mammography follow-up among minority and medically underserved women. Further comprehensive study of these concepts is warranted.

  8. The College Application Essay: A Rhetorical Paradox.

    ERIC Educational Resources Information Center

    Paley, Karen Surman

    An informal study explored the dynamics of the task of writing college application essays, which urge self-revelation but are judged by omnipotent admissions committees. Four students in the top 17% of their class of 194 in a predominantly white suburban school completed think-aloud protocols as they drafted a response to an application question…

  9. Learning Dilemmas in Undergraduate Student Independent Essays

    ERIC Educational Resources Information Center

    Wendt, Maria; Åse, Cecilia

    2015-01-01

    Essay-writing is generally viewed as the primary learning activity to foster independence and analytical thinking. In this article, we show that independent research projects do not necessarily lead to critical thinking. University-level education on conducting independent projects can, in several respects, counteract enhanced analytical skills.…

  10. Art for Many Purposes: A Photo Essay.

    ERIC Educational Resources Information Center

    Corwin, Sylvia K.

    1985-01-01

    An interdisciplinary art and science program for talented inner-city 11th graders is described through a photo essay. Students are involved in activities such as painting outdoors, rendering instructional charts for use in science classes, illustrating seasonal calendars, gardening, identifying insects, and learning about weather forecasting. (RM)

  11. The Beleaguered College. Essays on Educational Reform

    ERIC Educational Resources Information Center

    Tussman, Joseph

    The five essays of this book focus on educational reform in higher education and are based on several persistent themes: that there is a fatal conflict between the graduate school and the undergraduate college; that "liberal" education is in a fundamental sense "politics", therefore, an education needed by everyone for all in a…

  12. Starting with "I": Personal Essays by Teenagers.

    ERIC Educational Resources Information Center

    Estepa, Andrea, Ed.; Kay, Philip, Ed.

    In personal essays, teenagers express their views on serious subjects like violence, racism, and teen parenting, and discuss common teen experiences like dating, getting a job, and starting college. This collection contains the following: (1) "Brotherly Love" (Jessica Vicuna); (2) "How To Survive Shopping with Mom" (Chris Kanarick); (3) "A…

  13. Two Essays on the Learning Paradigm.

    ERIC Educational Resources Information Center

    Doud, Robert E.

    This document contains two essays, both of which discuss the ascendancy of the learning paradigm over the teaching paradigm. "Philosophy and the Learning Paradigm" reviews the effects of post-modernism on student learning with regard to loss of authority in the classroom, lack of academic standards in writing, and perceptions of…

  14. Assessment of Writing Skills through Essay Tests.

    ERIC Educational Resources Information Center

    Crocker, Linda

    1987-01-01

    Examines reasons for using essay tests in the direct assessment of writing ability. Reviews the steps in developing a large-scale testing program; e.g., creating a pool of topics or prompts; developing scoring procedures; training raters; field-testing the system; scoring writing samples; assessing reliability; and assessing validity. (DMM)

  15. Beyond the Five-Paragraph Essay

    ERIC Educational Resources Information Center

    Campbell, Kimberly Hill

    2014-01-01

    Although using the five-paragraph formula to teach essay writing is a ubiquitous practice--and many K-12 teachers defend it--Campbell argues that having students write according to this formula does more harm than good. The formula's tight structure stops the very critical thinking students need to do to strengthen their cognition and their…

  16. ESSAYS, ANALYSIS, AND--BETTER WRITING.

    ERIC Educational Resources Information Center

    STEWART, DONALD C.

    A STUDY OF THE NATURE AND UTILITY OF TYPES OF ESSAY ANTHOLOGIES DESIGNED FOR FRESHMAN COMPOSITION COURSES WAS CONDUCTED IN ORDER TO DETERMINE (1) WHAT ARE THE RATIONALES, ORGANIZATION, CONTENT, AND INSTRUCTIONAL APPARATUS OF THE MOST WIDELY ADOPTED READERS, (2) HAVE THE RATIONALES FOR THEIR USE VARIED SINCE SUCH TEXTS APPEARED, AND (3) IS THE…

  17. Essays on Classical Rhetoric and Modern Discourse.

    ERIC Educational Resources Information Center

    Connors, Robert J., Ed.; And Others

    Noting the rediscovery by composition scholars of the tradition of classical rhetoric, this collection of essays explores the resurgence in the teaching of written discourse in college English departments. The 18 articles and their authors are as follows: (1) "The Revival of Rhetoric in America," by Robert Connors, Lisa Ede, and Andrea…

  18. Audiotape Feedback for Essays in Distance Education.

    ERIC Educational Resources Information Center

    Kirschner, Paul A.; And Others

    1991-01-01

    Twelve students writing essays for a photochemistry course at the Open University of the Netherlands received either audiocasette or written feedback. Time spent in recording versus writing feedback differed minimally. Recorded feedback was considerably greater in amount. Students' final grades did not differ, but recorded feedback was more…

  19. ESSAYS ON THE SOCIAL SYSTEMS OF EDUCATION.

    ERIC Educational Resources Information Center

    BIDDLE, BRUCE J.; AND OTHERS

    THIS IS A COLLECTION OF ESSAYS PRODUCED BY MEMBERS OF AN INTERDISCIPLINARY SEMINAR REPRESENTING THE VARIOUS BEHAVIORAL SCIENCES. THE GROUP WAS GIVEN THE ASSIGNMENT OF CONCEPTUALIZING THE INFLUENCES OF MASS MEDIA UPON EDUCATION AS A SOCIAL INSTITUTION. THE SEMINAR WAS OF A YEAR'S DURATION AND WAS HELD AT THE UNIVERSITY OF MISSOURI. THE GROUP, IN…

  20. Revising: New Essays for Teachers of Writing.

    ERIC Educational Resources Information Center

    Sudol, Ronald A., Ed.

    Intended to help writing teachers better understand how to help students effectively revise their written work, this book contains essays that, as a group, focus on the problem of the definition of revision. The first half of the book discusses the background of revision, while the second half discusses contexts and techniques for application. The…

  1. Three Essays on the Economics of Education

    ERIC Educational Resources Information Center

    Herrmann, Mariesa Ann

    2012-01-01

    This dissertation consists of essays on three inputs into the educational production function: curriculum, peers, and teachers. The chapters are linked by their focus on understanding the importance of these inputs for student achievement and by their exploitation of the exact timing of events (i.e., student mobility, receipt of special education…

  2. Toward More Substantively Meaningful Automated Essay Scoring

    ERIC Educational Resources Information Center

    Ben-Simon, Anat; Bennett, Randy Elliott

    2007-01-01

    This study evaluated a "substantively driven" method for scoring NAEP writing assessments automatically. The study used variations of an existing commercial program, e-rater[R], to compare the performance of three approaches to automated essay scoring: a "brute-empirical" approach in which variables are selected and weighted solely according to…

  3. French Higher Education: A Cartoon Essay

    ERIC Educational Resources Information Center

    Hall, Matthew Henry

    2012-01-01

    In this cartoon essay, the author shares his experience from a travel to Paris to see the French higher education system. From his travel, he learned that in France, "degree" inflation may be an issue, but not grade inflation. On the flight home, the author reflects how French and American academics answer one question about the state of…

  4. Automated Essay Scoring: Psychometric Guidelines and Practices

    ERIC Educational Resources Information Center

    Ramineni, Chaitanya; Williamson, David M.

    2013-01-01

    In this paper, we provide an overview of psychometric procedures and guidelines Educational Testing Service (ETS) uses to evaluate automated essay scoring for operational use. We briefly describe the e-rater system, the procedures and criteria used to evaluate e-rater, implications for a range of potential uses of e-rater, and directions for…

  5. Essays on Legal and Illegal Immigration.

    ERIC Educational Resources Information Center

    Pozo, Susan, Ed.

    Major issues of the debate that led to the passage of an immigration reform bill are discussed and analyzed in this collection of six papers that were delivered as public lectures at Western Michigan University during the 1984-85 academic year. The essays reflect a broad range of views on the effects of immigration on the United States economy and…

  6. How Valid Are the Portland Baseline Essays?

    ERIC Educational Resources Information Center

    Martel, Erich

    1991-01-01

    Portland, Oregon's "African-American Baseline Essays," widely used in creating multicultural curricula, inaccurately depicts ancient Egyptians as black people and Olmec civilization as derived from African influences. The authors advance racial theories long abandoned by mainline Africa scholars, attribute mystical powers to pyramids,…

  7. Essays on Neighborhood Transition and Housing Markets

    ERIC Educational Resources Information Center

    Casey, Marcus D.

    2009-01-01

    This dissertation presents new evidence on neighborhood transition and its impact on housing markets using a novel micro-level dataset on housing transactions. It focuses on three issues: the neighborhood effect, housing discrimination, and stable integration. The first essay examines the relationship between increased minority composition and…

  8. The Theory of the Novel: New Essays.

    ERIC Educational Resources Information Center

    Halperin, John, Ed.

    This collection, containing essays by contemporary critics, analyzes such aspects of the novel as structure, history, point of view, techniques, and its future. Included are "What is Exposition?" by Meir Sternberg; "Notes Toward a Comic Fiction" by Robert B. Martin; "The Aesthetics of the Supra-Novel" by Irving H.…

  9. Degrees of Disenchantment: A Review Essay

    ERIC Educational Resources Information Center

    Brenneman, Mark; Margonis, Frank

    2012-01-01

    In this review essay, Mark Brenneman and Frank Margonis address three recent book-length contributions to the ongoing discussion around cosmopolitanism and educational thought: Mark Olssen's "Liberalism, Neoliberalism, Social Democracy: Thin Communitarian Perspectives on Political Philosophy and Education," Sharon Todd's "Toward an Imperfect…

  10. Social Responsibility in Librarianship: Essays on Equality.

    ERIC Educational Resources Information Center

    MacCann, Donnarae, Ed.

    In a culturally complex world, librarians can best work toward the equalization of library services if they understand their institutions in the light of cultural history. The six essays in this book highlight problems that affect unempowered populations, and address a variety of cultural problems and biases--problems that contribute to the…

  11. The Vision of Sequoyah: A Bibliographic Essay.

    ERIC Educational Resources Information Center

    Wagner, Elaine

    In 1821, Sequoyah, a Cherokee Indian, presented to his tribal council a syllabary of the Cherokee language--an invention that enabled a previously illiterate people to read and write in their own language. This document includes a brief essay describing Sequoyah's life and accomplishment and a bibliography of further resources. Sequoyah was born…

  12. TV as Art: Some Essays in Criticism.

    ERIC Educational Resources Information Center

    Hazard, Patrick D., Ed.

    Based on the beliefs that television can be a legitimate art form and that the development of judgment about television programs is one of the serious responsibilities of the schools, this collection of critiques of television programs is intended for teachers at every level of instruction. Essays are (1) "'TV as Art': Some Reflections" by Patrick…

  13. Education and Place: A Review Essay

    ERIC Educational Resources Information Center

    Nespor, Jan

    2008-01-01

    In this review essay, Jan Nespor uses three recent contributions to place-based education, Paul Theobald's "Teaching the Commons," C.A. Bowers's "Revitalizing the Commons," and David Gruenewald and Gregory Smith's edited volume "Place-Based Education in the Global Age," to examine some fundamental conceptual and practical issues in the area. One…

  14. Clinical value of mammography in diagnosis and identification of breast mass

    PubMed Central

    Li, Hongjun; Zhang, Shanhua; Wang, Qingyuan; Zhu, Rongguang

    2016-01-01

    Objective: To study the effect and clinical value of mammography in the diagnosis of breast lump so as to improve the diagnosis level of breast cancer. Methods: A retrospective analysis was carried out on clinical data of 110 patients with mammary lump confirmed by pathology to study the compliance of mammography diagnosis and Pathology diagnosis in breast lump, and the detection of microcalcifications, phyllode, and observe the image performance of mammography. Taking infitrating ductal carcinoma (IDC) as an example, the correlation of image performance and clinical pathological features of different types was studied so as to predict if mammography performance was effective in the treatment and prognosis in breast cancer. Results: Taking Breast Imaging Reporting and Data System (BI-RADS) grade 4A as the critical point, the sensitivity, specificity and accuracy of mammography was 90.80% (109/120), 84.60% (126/149) and 87.40% (235/269); taking BI-RADS grade 4B as the critical point, the sensitivity, specificity and accuracy of mammography was 85.00% (102/120), 93.30% (139/149) and 89.60% (241/269); the correlation analysis suggested that, there was some kind of correlation between the mammography performance and clinical features of breast cancer. Conclusion: Mammography is worth being promoted in clinic for its significant clinical value in diagnosing and identifying breast lump. PMID:27648060

  15. Latinas’ Mammography Intention Following a Home-Based Promotores–Led Intervention

    PubMed Central

    Scheel, John R.; Molina, Yamile; Briant, Katherine J.; Ibarra, Genoveva; Lehman, Constance D.; Thompson, Beti

    2015-01-01

    Despite increases in mammography rates among Latinas, screening rates remain lower than in non-Latina Whites (NLW) and Latinas typically present with breast cancer at a later stage. Trained lay community workers (promotores) have been successfully used to increase screening mammography intention in Latinas. Little is known, however, about the potential mechanisms of these interventions, such as increased breast cancer knowledge (knowledge) and social interactions concerning mammography practices (social engagement). This prospective pre-post study examined this gap in the literature by 1) documenting changes in knowledge and social engagement after receipt of a promotores-based intervention; and 2) establishing if post-intervention knowledge and social engagement predicted mammography intention, after adjusting for socio-demographic and lifetime mammography history. There were significant increases in knowledge and social engagement about mammography. Finally, post-intervention social engagement was a significant predictor of mammography intention. Future promotores-based interventions should focus on enhancing social engagement to improve mammography intention and use. PMID:26063674

  16. 75 FR 70011 - Guidance for Industry, Mammography Quality Standards Act Inspectors, and Food and Drug...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-16

    ... HUMAN SERVICES Food and Drug Administration Guidance for Industry, Mammography Quality Standards Act Inspectors, and Food and Drug Administration Staff; The Mammography Quality Standards Act Final Regulations: Modifications and Additions to Policy Guidance Help System 13; Availability AGENCY: Food and Drug...

  17. Cultural Views, Language Ability, and Mammography Use in Chinese American Women

    ERIC Educational Resources Information Center

    Liang, Wenchi; Wang, Judy; Chen, Mei-Yuh; Feng, Shibao; Yi, Bin; Mandelblatt, Jeanne S.

    2009-01-01

    Mammography screening rates among Chinese American women have been reported to be low. This study examines whether and how culture views and language ability influence mammography adherence in this mostly immigrant population. Asymptomatic Chinese American women (n = 466) aged 50 and older, recruited from the Washington, D.C. area, completed a…

  18. Attitudes and Beliefs Associated with Mammography in a Multiethnic Population in Israel

    ERIC Educational Resources Information Center

    Baron-Epel, Orna

    2010-01-01

    This article highlights beliefs, attitudes, and barriers that are associated with mammography use in four distinct cultural and ethnic groups in Israel: veteran, ultra-orthodox, and immigrant Jewish and Arab women. A random telephone survey of 1,550 women was performed. Information from claims records concerning mammography use was obtained for…

  19. Latinas' Mammography Intention Following a Home-Based Promotores-Led Intervention.

    PubMed

    Scheel, John R; Molina, Yamile; Briant, Katherine J; Ibarra, Genoveva; Lehman, Constance D; Thompson, Beti

    2015-12-01

    Despite increases in mammography rates among Latinas, screening rates remain lower than in non-Latina Whites and Latinas typically present with breast cancer at a later stage. Trained lay community workers (promotores) have been successfully used to increase screening mammography intention in Latinas. Little is known, however, about the potential mechanisms of these interventions, such as increased breast cancer knowledge (knowledge) and social interactions concerning mammography practices (social engagement). This prospective pre-post study examined this gap in the literature by (1) documenting changes in knowledge and social engagement after receipt of a promotores-based intervention; and (2) establishing if post-intervention knowledge and social engagement predicted mammography intention, after adjusting for socio-demographic and lifetime mammography history. There were significant increases in knowledge and social engagement about mammography. Finally, post-intervention social engagement was a significant predictor of mammography intention. Future promotores-based interventions should focus on enhancing social engagement to improve mammography intention and use.

  20. Mammography use among women with and without diabetes: results from the Southern Community Cohort Study.

    PubMed

    Sanderson, Maureen; Lipworth, Loren; Han, Xijing; Beeghly-Fadiel, Alicia; Shen-Miller, David; Patel, Kushal; Blot, William J; Hargreaves, Margaret K

    2014-09-01

    Studies have shown an increased risk of breast cancer associated with diabetes which may be due to differences in mammography use among women who have diabetes compared with women who do not have diabetes. Baseline data was used from the Southern Community Cohort Study - a prospective cohort study conducted primarily among low-income persons in the southeastern United States - to examine the association between diabetes and mammography use. In-person interviews collected information on diabetes and mammography use from 14,665 white and 30,846 black women aged 40-79years between 2002 and 2009. After adjustment for potential confounding, white women with diabetes were no more likely (odds ratio [OR] 0.95, 95% confidence interval [CI] 0.85-1.06) to undergo mammography within the past 12months than white women without diabetes. Nor was there an association between diabetes and mammography use among black women (OR 1.00, 95% CI 0.93-1.07). An increase in mammography use was seen within one year following diabetes diagnosis, more so among white than black women, but this was offset by decreases thereafter. Although there was some evidence of an increase in mammography use within one year of diabetes diagnosis, these results suggest that mammography use is not related to diabetes.

  1. Does Distance Matter? Distance to Mammography Facilities and Stage at Diagnosis of Breast Cancer in Kentucky

    ERIC Educational Resources Information Center

    Huang, Bin; Dignan, Mark; Han, Daikwon; Johnson, Owen

    2009-01-01

    Background: National and regional data indicate that breast cancer early detection is low in Kentucky, especially rural regions, perhaps because access to mammography services can be problematic. Objective: This study examined the distance between residences of women diagnosed with breast cancer and the nearest mammography facility, as a risk…

  2. First detection of hydrogen in the β Pictoris gas disk

    NASA Astrophysics Data System (ADS)

    Wilson, P. A.; Lecavelier des Etangs, A.; Vidal-Madjar, A.; Bourrier, V.; Hébrard, G.; Kiefer, F.; Beust, H.; Ferlet, R.; Lagrange, A.-M.

    2017-03-01

    The young and nearby star β Pictoris (β Pic) is surrounded by a debris disk composed of dust and gas known to host a myriad evaporating exocomets, planetesimals and at least one planet. At an edge-on inclination, as seen from Earth, this system is ideal for debris disk studies providing an excellent opportunity to use absorption spectroscopy to study the planet forming environment. Using the Cosmic Origins Spectrograph (COS) instrument on the Hubble Space Telescope (HST) we observe the most abundant element in the disk, hydrogen, through the H I Lyman α (Ly-α) line. We present a new technique to decrease the contamination of the Ly-α line by geocoronal airglow in COS spectra. This Airglow Virtual Motion (AVM) technique allows us to shift the Ly-α line of the astrophysical target away from the contaminating airglow emission revealing more of the astrophysical line profile. This new AVM technique, together with subtraction of an airglow emission map, allows us to analyse the shape of the β Pic Ly-α emission line profile and from it, calculate the column density of neutral hydrogen surrounding β Pic. The column density of hydrogen in the β Pic stable gas disk at the stellar radial velocity is measured to be log (NH/ 1 cm2) ≪ 18.5. The Ly-α emission line profile is found to be asymmetric and we propose that this is caused by H I falling in towards the star with a bulk radial velocity of 41 ± 6 km s-1 relative to β Pic and a column density of log (NH/ 1 cm2) = 18.6 ± 0.1. The high column density of hydrogen relative to the hydrogen content of CI chondrite meteorites indicates that the bulk of the hydrogen gas does not come from the dust in the disk. This column density reveals a hydrogen abundance much lower than solar, which excludes the possibility that the detected hydrogen could be a remnant of the protoplanetary disk or gas expelled by the star. We hypothesise that the hydrogen gas observed falling towards the star arises from the dissociation of

  3. VLT imaging of the β Pictoris gas disk

    NASA Astrophysics Data System (ADS)

    Nilsson, R.; Brandeker, A.; Olofsson, G.; Fathi, K.; Thébault, Ph.; Liseau, R.

    2012-08-01

    Context. Circumstellar debris disks older than a few Myr should be largely devoid of primordial gas remaining from the protoplanetary disk phase. Tracing the origin of observed atomic gas in Keplerian rotation in the edge-on debris disk surrounding the ~12 Myr old star β Pictoris requires more detailed information about its spatial distribution than has previously been acquired by limited slit spectroscopy. Especially indications of asymmetries and presence of Ca ii gas at high disk latitudes call for additional investigation to exclude or confirm its connection to observed dust structures or suggested cometary bodies on inclined eccentric orbits. Aims: We set out to recover a complete image of the Fe i and Ca ii gas emission around β Pic by spatially resolved, high-resolution spectroscopic observations to better understand the morphology and origin of the gaseous disk component. Methods: The multiple fiber facility FLAMES/GIRAFFE at the Very Large Telescope (VLT), with the large integral-field-unit ARGUS, was used to obtain spatially resolved optical spectra (from 385.9 to 404.8 nm) in four regions covering the northeast and southwest side of the disk. Emission lines from Fe i (at 386.0 nm) and Ca ii (at 393.4 and 396.8 nm) were mapped and could be used to fit a parametric function for the disk gas distribution, using a gas-ionisation code for gas-poor debris disks. Results: Both Fe i and Ca ii emission are clearly detected, with the former dominating along the disk midplane, and the latter revealing vertically more extended gas. The surface intensity of the Fe i emission is lower but more extended in the northeast (reaching the 210 AU limit of our observations) than in the southwest, while Ca ii shows the opposite asymmetry. The modelled Fe gas disk profile shows a linear increase in scale height with radius, and a vertical profile that suggests dynamical interaction with the dust. We also qualitatively demonstrate that the Ca ii emission profile can be

  4. Physical and orbital properties of β Pictoris b

    NASA Astrophysics Data System (ADS)

    Bonnefoy, M.; Marleau, G.-D.; Galicher, R.; Beust, H.; Lagrange, A.-M.; Baudino, J.-L.; Chauvin, G.; Borgniet, S.; Meunier, N.; Rameau, J.; Boccaletti, A.; Cumming, A.; Helling, C.; Homeier, D.; Allard, F.; Delorme, P.

    2014-07-01

    The intermediate-mass star β Pictoris is known to be surrounded by a structured edge-on debris disk within which a gas giant planet was discovered orbiting at 8-10 AU. The physical properties of β Pic b were previously inferred from broad- and narrow-band 0.9-4.8 μm photometry. We used commissioning data of the Gemini Planet Imager (GPI) to obtain new astrometry and a low-resolution (R ~ 35-39) J-band (1.12-1.35 μm) spectrum of the planet. We find that the planet has passed the quadrature. We constrain its semi-major axis to ≤10 AU (90% prob.) with a peak at 8.9+0.4-0.6 AU. The joint fit of the planet astrometry and the most recent radial velocity measurements of the star yields a planet dynamical mass lower than 20 MJup (≥96% prob.). The extracted spectrum of β Pic b is similar to those of young L1-1.5+1 dwarfs. We used the spectral type estimate to revise the planet luminosity to log (L/L⊙) = -3.90 ± 0.07. The 0.9-4.8 μm photometry and spectrum are reproduced for Teff = 1650 ± 150 K and a log g ≤ 4.7 dex by 12 grids of PHOENIX-based and LESIA atmospheric models. For the most recent system age estimate (21 ± 4 Myr), the bolometric luminosity and the constraints on the dynamical mass of β Pic b are only reproduced by warm- and hot-start tracks with initial entropies Si> 10.5 kB/baryon. These initial conditions may result from an inefficient accretion shock and/or a planetesimal density at formation higher than in the classical core-accretion model. Considering a younger age for the system or a conservative formation time for β Pic b does not change these conclusions. Appendices are available in electronic form at http://www.aanda.org

  5. Examining Pictorial Models and Virtual Manipulatives for Third-Grade Fraction Instruction

    ERIC Educational Resources Information Center

    Moyer-Packenham, Patricia S.; Ulmer, Lori A.; Anderson, Katie L.

    2012-01-01

    The purpose of this study was to examine pictorial representations, whether in static or dynamic modalities, and their impact on student learning in a classroom with low-achieving students. The investigation emerged from a classroom teacher's action research project. During a three-week fraction unit, nineteen third-grade low-achieving students…

  6. Use of Pictorial Evaluations to Measure Knowledge Gained by Hispanic Landscape Workers Receiving Safety Training

    ERIC Educational Resources Information Center

    Bauske, Ellen M.; Fuhrman, Nicholas E.; Martinez-Espinoza, Alfredo D.; Orellana, Rolando

    2013-01-01

    Landscape work is dangerous. In the Southeast, Hispanic workers predominate in landscape industries. The incidence of functional illiteracy in this group of workers is high. A pictorial knowledge-based evaluation instrument was developed to measure the effectiveness of the trainings. No reading skills were required to take the evaluation. The…

  7. Children's Independent Exploration of a Natural Phenomenon by Using a Pictorial Computer-Based Simulation.

    ERIC Educational Resources Information Center

    Kangassalo, Marjatta

    Using a pictorial computer simulation of a natural phenomenon, children's exploration processes and their construction of conceptual models were examined. The selected natural phenomenon was the variations of sunlight and heat of the sun experienced on the earth in relation to the positions of the earth and sun in space, and the subjects were…

  8. Psychometric Comparisons of the Pictorial Child Behavior Checklist with the Standard Version of the Instrument

    ERIC Educational Resources Information Center

    Leiner, Marie; Rescorla, Leslie; Medina, Irma; Blanc, Oscar; Ortiz, Melchor

    2010-01-01

    The low level of literacy and lack of language proficiency possessed by some immigrants from low socioeconomic status backgrounds create communication barriers in the healthcare setting, thus interfering with their ability to access appropriate medical care and their subsequent participation in medical research. Adding pictorial descriptions to…

  9. Pictorial Aids for Learning by Doing in a Multimedia Geology Simulation Game.

    ERIC Educational Resources Information Center

    Mayer, Richard E.; Mautone, Patricia; Prothero, William

    2002-01-01

    The task was to survey an area of a planet's surface to identify the presence of various geological features such as a trench, ridge, or basin. Students who received prior pictorial representations of features performed more accurately than students who did not, but there was no significant effect for including verbal statements about strategies…

  10. The Pictorial Fire Stroop: A Measure of Processing Bias for Fire-Related Stimuli

    ERIC Educational Resources Information Center

    Gallagher-Duffy, Joanne; MacKay, Sherri; Duffy, Jim; Sullivan-Thomas, Meara; Peterson-Badali, Michele

    2009-01-01

    Fire interest is a risk factor for firesetting. This study tested whether a fire-specific emotional Stroop task can effectively measure an information-processing bias for fire-related stimuli. Clinic-referred and nonreferred adolescents (aged 13-16 years) completed a pictorial "Fire Stroop," as well as a self-report fire interest questionnaire and…

  11. Near, yet so Far: The Effect of Pictorial Cues on Spatial Attention

    ERIC Educational Resources Information Center

    Nicholls, Michael E. R.; Forte, Jason D.; Loetscher, Tobias; Orr, Catherine A.; Yates, Mark J.; Bradshaw, John L.

    2011-01-01

    Distinct cognitive and neural mechanisms underlie perception and action in near (within-reach) and far (outside-reach) space. Objects in far space can be brought into the brain's near-space through tool-use. We determined whether a near object can be pushed into far space by changing the pictorial context in which it occurs. Participants (n = 372)…

  12. Veridical and False Pictorial Memory in Individuals with and without Mental Retardation

    ERIC Educational Resources Information Center

    Carlin, Michael T.; Toglia, Michael P.; Wakeford, Yvonne; Jakway, Allison; Sullivan, Kate; Hasel, Lisa

    2008-01-01

    Veridical and false pictorial recognition were assessed in individuals with mental retardation; groups were matched for MA and CA. Pictures were viewed in either a generative or static format at acquisition. The individuals with mental retardation and those in the MA-matched group had higher rates of false memories for critical items and lower hit…

  13. 14. Photocopy of drawing (from: Lossing, Benson, J. Pictorial FieldBook ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    14. Photocopy of drawing (from: Lossing, Benson, J. Pictorial Field-Book of the Revolution. (New York: Harper & Brothers, 1855), Vol. 2, p. 180.) ca. 1855, delineator unknown WEST SIDE AND SOUTH FRONT - John Chad House, State Route 100, U.S. Route 1 vicinity, Chadds Ford, Delaware County, PA

  14. Validation of the Pictorial Infant Communication Scale for preschool-aged children with autism spectrum disorder.

    PubMed

    Ghilain, Christine S; Parlade, Meaghan V; McBee, Matthew T; Coman, Drew C; Owen, Taylor; Gutierrez, Anibal; Boyd, Brian; Odom, Samuel; Alessandri, Michael

    2017-02-01

    Joint attention, or the shared focus of attention between objects or events and a social partner, is a crucial milestone in the development of social communication and a notable area of deficit in children with autism spectrum disorder. While valid parent-report screening measures of social communication are available, the majority of these measures are designed to assess a wide range of behaviors. Targeted assessment of joint attention and related skills is primarily limited to semi-structured, examiner-led interactions, which are time-consuming and laborious to score. The Pictorial Infant Communication Scale is an efficient parent-report measure of joint attention that can be used as a complement to structured assessments in fully characterizing early social communication development. This study examined the psychometric properties of the Pictorial Infant Communication Scale. Results revealed a high degree of internal consistency and strong intercorrelations between subscales. Additionally, confirmatory factor analysis supported a three-factor model of joint attention. Furthermore, significant correlations between the Pictorial Infant Communication Scale and direct clinical measures of child joint attention, language skills, and autism spectrum disorder symptom severity were suggestive of concurrent validity. Findings suggest that the Pictorial Infant Communication Scale is a promising tool for measuring joint attention skills in preschool-aged children with autism spectrum disorder.

  15. The Effectiveness of Electronic Text and Pictorial Graphic Organizers to Improve Comprehension Related to Functional Skills

    ERIC Educational Resources Information Center

    Douglas, Karen H.; Ayres, Kevin M.; Langone, John; Bramlett, Virginia Bell

    2011-01-01

    This study evaluated the effects of a computer-based instructional program to assist three students with mild to moderate intellectual disabilities in using pictorial graphic organizers as aids for increasing comprehension of electronic text-based recipes. Student comprehension of recipes was measured by their ability to verbally retell recipe…

  16. Cognitive Load in Percentage Change Problems: Unitary, Pictorial, and Equation Approaches to Instruction

    ERIC Educational Resources Information Center

    Ngu, Bing Hiong; Yeung, Alexander Seeshing; Tobias, Stephen

    2014-01-01

    Eighth grade students in Australia (N = 60) participated in an experiment on learning how to solve percentage change problems in a regular classroom in three conditions: unitary, pictorial, and equation approaches. The procedure involved a pre-test, an acquisition phase, and a post-test. The main goal was to test the relative merits of the three…

  17. Ernst H. Gombrich, Pictorial Representation, and Some Issues in Art Education

    ERIC Educational Resources Information Center

    Kim, Nanyoung

    2004-01-01

    This paper deals with the main theses of Gombrich's theory of pictorial representation as they pertain to the understanding of representational artworks and children's drawing. It is argued that the current linguistic-cognitive model of representation adopted from Goodman's theory provides an understanding of images and children's drawing in art…

  18. The Pictorial Scale of Perceived Competence and Social Acceptance for Young Children.

    ERIC Educational Resources Information Center

    Harter, Susan; Pike, Robin

    1984-01-01

    Describes two versions of a new pictorial scale of perceived competence and social acceptance, a downward extension of the Perceived Competence Scale for Children. Both versions, one for preschoolers/kindergarteners and one for first/second graders, tap four domains: cognitive competence, physical competence, peer acceptance, and maternal…

  19. On the Power of Fine Arts Pictorial Imagery in Science Education

    ERIC Educational Resources Information Center

    Galili, Igal

    2013-01-01

    The paper describes and illustrates the potential of using pictorial artistic images in supporting teaching scientific concepts and the nature of science. In the first part, the case of Giotto's fresco of stigmatization of St. Francis is described within the interpretation of relationship between the figures as between an object and its…

  20. Pictorial Vs. Verbal Stimuli in Posttest Items. Speical Report No. 7319.

    ERIC Educational Resources Information Center

    Lord, Harold C.

    The purpose of this pilot study was to test the hypothesis that the mean number of correct responses to pictorial items (line drawings) would be significantly higher than the mean number of correct responses to verbal (printed word) items. The items tested were selected from the items included in a posttest administered to 33 first grade students…

  1. Imaging of adult ocular and orbital pathology--a pictorial review.

    PubMed

    Grech, Reuben; Cornish, Kurt Spiteri; Galvin, Patrick Leo; Grech, Stephan; Looby, Seamus; O'Hare, Alan; Mizzi, Adrian; Thornton, John; Brennan, Paul

    2014-02-01

    Orbital pathology often presents a diagnostic challenge to the reporting radiologist. The aetiology is protean, and clinical input is therefore often necessary to narrow the differential diagnosis. With this manuscript, we provide a pictorial review of adult ocular and orbital pathology.

  2. The Effects of Varying Pictorial Detail and Presentation Strategy on Concept Formation.

    ERIC Educational Resources Information Center

    Gorman, Don A.

    The purpose of this study is to determine the effects of varying pictorial detail and presentation strategy on learners of varying grade levels in a visually transmitted concept formation task. Specifically, line drawings containing only relevant details and halftones containing relevant and irrelevant detail were presented successively and…

  3. Interaction of Learner Characteristics with Pictorial Adjuncts in Learning from Science Text.

    ERIC Educational Resources Information Center

    Koran, Mary Lou; Koran, John J., Jr.

    1980-01-01

    Investigates whether placement of pictorial adjuncts before or after related textual material enhances instructional effectiveness for learners of varying ability. Junior high students (N=84) were randomly assigned to one or three treatments in which a diagram of the hydrologic cycle was inserted before, after, or omitted from the text. (CS)

  4. Translation of P = kT into a Pictorial External Representation by High School Seniors

    ERIC Educational Resources Information Center

    Matijaševic, Igor; Korolija, Jasminka N.; Mandic, Ljuba M.

    2016-01-01

    This paper describes the results achieved by high school seniors on an item which involves translation of the equation P = kT into a corresponding pictorial external representation. The majority of students (the classes of 2011, 2012 and 2013) did not give the correct answer to the multiple choice part of the translation item. They chose pictorial…

  5. Recognition of Pictorial Material As A Function of Experiential Deprivation and Age.

    ERIC Educational Resources Information Center

    Misra, Girishwar; Shukla, Aradhana

    1984-01-01

    Investigated relative effects of chronological age and experiential deprivation upon pictorial recognition. Four age levels (ages four to five, five to six, six to seven, and seven to eight years) and two levels of deprivation were manipulated. The 50 subjects in each factorial cell performed tasks individually. (Author/RH)

  6. A Novel Pictorial Approach to Teaching Molecular Motions in Polyatomic Molecules.

    ERIC Educational Resources Information Center

    Verkade, John G.

    1987-01-01

    Describes a procedure for teaching the "generator orbital" (GO) approach of molecular orbital bonding in polyatomic molecules. Explains how the GO can be utilized with students in generating the vibrational, rotational, and translational modes of molecules in a completely pictorial manner. (ML)

  7. Do Adults with Mental Retardation Show Pictorial Superiority Effects in Recall and Recognition?

    ERIC Educational Resources Information Center

    Cherry, Katie E.; Applegate, Heather; Reese, Celinda M.

    2002-01-01

    A study examined memory for pictures and words in 16 adults with mental retardation and 24 controls. Pictorial superiority effects occurred in free recall and recognition for both intelligence-level groups. Correlational analyses indicated working memory span was primarily related to recall performance, irrespective of stimulus format. (Contains…

  8. Memory for Pictures, Words, and Spatial Location in Older Adults: Evidence for Pictorial Superiority.

    ERIC Educational Resources Information Center

    Park, Denise Cortis; And Others

    1983-01-01

    Tested recognition memory for items and spatial location by varying picture and word stimuli across four slide quadrants. Results showed a pictorial superiority effect for item recognition and a greater ability to remember the spatial location of pictures versus words for both old and young adults (N=95). (WAS)

  9. Cognitive Differences in Pictorial Reasoning between High-Functioning Autism and Asperger's Syndrome

    ERIC Educational Resources Information Center

    Sahyoun, Cherif P.; Soulieres, Isabelle; Belliveau, John W.; Mottron, Laurent; Mody, Maria

    2009-01-01

    We investigated linguistic and visuospatial processing during pictorial reasoning in high-functioning autism (HFA), Asperger's syndrome (ASP), and age and IQ-matched typically developing participants (CTRL), using three conditions designed to differentially engage linguistic mediation or visuospatial processing (visuospatial, V; semantic, S;…

  10. National Apprenticeship and Training Standards for the Sign, Pictorial Display, Electric Sign and Process Industry.

    ERIC Educational Resources Information Center

    National Joint Apprenticeship and Training Committee for the Sign, Pictorial Display, Electric Sign, and Process Industry, Washington, DC.

    Revised national standards for sign, pictorial display, electric sign, and process apprenticeships were developed to provide guidelines to local employers and labor groups to be used in setting up and operating uniform and effective apprenticeship programs. The apprenticeship term is 10,000 hours or 5 years of on-the-job training subdivided into…

  11. The Influence of Breast Self-Examination on Subsequent Mammography Participation

    PubMed Central

    Jelinski, Susan E.; Maxwell, Colleen J.; Onysko, Jay; Bancej, Christina M.

    2005-01-01

    Objectives. We evaluated whether breast self-examination (BSE) influences subsequent mammography participation. Methods. We evaluated associations between BSE and subsequent mammography participation, adjusting for baseline screening behaviors and sociodemographic, health, and lifestyle characteristics, among women aged 40 years and older using data from the longitudinal Canadian National Population Health Survey. Results. Regular performance of BSE at baseline was not associated with receipt of a recent mammogram at follow-up among all women (adjusted odds ratio [OR]=1.01; 95% confidence interval [CI]= 0.75, 1.35) or with mammography uptake among the subgroup of women reporting never use at baseline (adjusted OR=0.78; 95% CI=0.50, 1.22). Conclusions. The lack of association between performance of BSE and subsequent mammography participation suggests that not recommending BSE is unlikely to influence mammography participation. PMID:15727985

  12. Obesity, Gynecological Factors, and Abnormal Mammography Follow-Up in Minority and Medically Underserved Women

    PubMed Central

    Wujcik, Debra; Lin, Jin-Mann S.; Grau, Ana; Wilson, Veronica; Champion, Victoria; Zheng, Wei; Egan, Kathleen M.

    2009-01-01

    Abstract Background The relationship between obesity and screening mammography adherence has been examined previously, yet few studies have investigated obesity as a potential mediator of timely follow-up of abnormal (Breast Imaging Reporting and Data System [BIRADS-0]) mammography results in minority and medically underserved patients. Methods We conducted a retrospective cohort study of 35 women who did not return for follow-up >6 months from index abnormal mammography and 41 who returned for follow-up ≤6 months in Nashville, Tennessee. Patients with a BIRADS-0 mammography event in 2003–2004 were identified by chart review. Breast cancer risk factors were collected by telephone interview. Multivariate logistic regression was performed on selected factors with return for diagnostic follow-up. Results Obesity and gynecological history were significant predictors of abnormal mammography resolution. A significantly higher frequency of obese women delayed return for mammography resolution compared with nonobese women (64.7% vs. 35.3%). A greater number of hysterectomized women returned for diagnostic follow-up compared with their counterparts without a hysterectomy (77.8% vs. 22.2%). Obese patients were more likely to delay follow-up >6 months (adjusted OR 4.09, p = 0.02). Conversely, hysterectomized women were significantly more likely to return for timely mammography follow-up ≤6 months (adjusted OR 7.95, p = 0.007). Conclusions Study results suggest that weight status and gynecological history influence patients' decisions to participate in mammography follow-up studies. Strategies are necessary to reduce weight-related barriers to mammography follow-up in the healthcare system including provider training related to mammography screening of obese women. PMID:19558307

  13. Pictorial health warnings on cigarette packs and the impact on women

    PubMed Central

    Bittencourt, Lorna; Person, Sharina D; Cruz, Regina Celina; Scarinci, Isabel C

    2013-01-01

    OBJECTIVE To analyze the association between the pictorial graphic health warnings on cigarette packs and their impact on intention to quit smoking among women. METHODS Population-based cross-sectional study among 265 women daily smokers in the State of Paraná in 2010. The sample size was calculated using cluster sampling. Participants were asked whether they had seen any pictorial graphic health warnings in the past 30 days, whether these warnings made them think about quitting, and intensity of these thoughts. The data was analyzed using logistic regression and the independent variables included age, educational attainment, whether they had children, whether they had attempted to quit smoking in the past 12 months, age of smoking initiation, number of cigarettes smoked per day, their town of residence, and how soon after waking do they smoke their first cigarette. RESULTS Participants (91.7%) reported seeing the pictorial graphic health warnings in the past 30 days. Women with elementary education or below and women with some/complete high school education were more likely to think about quitting smoking after seeing the pictorial graphic health warningsthan women with higher education (OR = 4.85; p = 0.0028 and OR = 2.91; p = 0.05), respectively). Women who attempted to quit smoking in the past 12 months were more likely to think about quitting than women who had not (OR = 2.49; p = 0.001). Quit attempts within the last 12 months were associated with intensity of these thoughts (OR = 2.2; p = 0.03). CONCLUSIONS Results show an association between pictorial graphic health warnings and intent to quit smoking among women with warnings having a greater impact among women with less education and who had attempted to quit smoking within the past year. Tobacco control strategies should be implemented across all groups of women regardless of their educational attainment. PMID:24626550

  14. Three-Dimensional Stereographic Pictorial Visual Interfaces And Display Systems In Flight Simulation

    NASA Astrophysics Data System (ADS)

    Bridges, Alan L.; Reising, John M.

    1987-06-01

    By combining stereoscopic aspects of vision with other optical clues, the pilot of a flight simulator is able to perceive true three-dimensional representations of pictorial display formats or simulated visual scenes. Three-dimensional (3-D) stereographic pictorial formats and their corresponding display systems are being developed and evaluated in order to determine the payoffs of the 3-D computer-generated display formats in the cockpit. The objectives of this research in true three-dimensional cockpit imagery are 1) to determine whether a pilot can better interpret complex pictorial display formats or visual scenes when the third dimension is added and 2) to determine how motion and depth cues can be used to tightly couple the human responses of the pilot to the aircraft control systems. This paper reviews current research, development, and evaluation of easily modifiable 3-D stereo-graphic pictorial display systems being used at the Advanced Cockpit Display Laboratory (ACDL), Lockheed-Georgia Company and at the Flight Dynamics Laboratory, Wright-Patterson AFB. This research includes the analysis and development of true 3-D pictorial formats representing the entire 3-D flight profile; e.g., displays for terrain following/terrain avoidance/threat avoidance and air-to-air and air-to-surface weapon delivery. Electro-optical shuttering systems; e.g., active and passive liquid crystal shutters (LCSs), stereographic display systems, and high-performance pseudo 3-D computer graphics workstations (Silicon Graphics IRIS), are being used to generate stereo pairs. Sidestick and throttle controllers are used to fly through the visual database. These near real-time simulations will be performed in realistic fighter and transport cockpit shells, which may evolve into 1995 designs.

  15. [How would plain packaging and pictorial warning impact on smoking reduction, cessation and initiation?].

    PubMed

    Mannocci, Alice; Colamesta, Vittoria; Mipatrini, Daniele; Boccia, Antonio; Terzano, Claudio; La Torre, Giuseppe

    2013-01-01

    The European Commission has proposed a review of the directive on tobacco products on labeling and packaging of tobacco products by introducing warning text with pictorial warning that occupies 75% of the cigarette packages. The aim of the survey was to assess the impact of plain packaging and pictorial warning in smoking reduction, cessation and initiation among a sample of adult. The cross-sectional study was conducted in Rome between September and November 2012. The questionnaires administered were 227, with a response rate of 82.4%. 35.8% (No. 67) of the respondents considered the image of the gangrene the most effective in communicating smoking-related damages, followed by the image on lung cancer (No. 60; 32.1%). Distinguishing between smokers and non-smokers (both former and never smokers), the picture on lung cancer was the most effective for smokers (No. 22; 38.6%); if cigarette packages have pictorial warnings like the ones shown, more than half (No. 33; 57.9%) of smokers would change brand; 66.7% (No. 38) of them would feel uncomfortable in showing the package. Comparing the 3 packagings, classic packaging, plain packaging with textual warning, and plain packaging with both textual and pictorial warning, the majority of people declared that the third is the most effective in preventing smoking initiation (No. 169; 90.9%), in motivating to quit (No. 158; 84.9%), and in changing smoking habits (No. 149; 80.5%). The survey, although its small sample size and being not representative of all strata of Italian population, shows that the plain packaging with pictorial warning is the most convincing in the three outcomes considered.

  16. Essay Development and Organization for the GED Examination.

    ERIC Educational Resources Information Center

    Tubman, Alan

    Developed as a teaching aid for a General Educational Development (GED) preparation class, this essay writing guide gives students the tools they need to develop and organize ideas for writing an essay with confidence. By following a sequential procedure in this very structured approach, students learn to turn out a well-organized essay. The…

  17. Essays on Occupational Education in the Two-Year College.

    ERIC Educational Resources Information Center

    Gillie, Angelo C.

    The eight essays in this document concern occupational education in the 2-year college. The first two essays present an overview of the community college and its role in providing post-secondary occupational education for contemporary American society. Three essays concern the curriculum for occupational education, emphasizing the needs of urban…

  18. An Interim Report on the MCAT Essay Pilot Project.

    ERIC Educational Resources Information Center

    Koenig, Judith Anderson; Mitchell, Karen J.

    1988-01-01

    The results from four pilot administrations of the Medical College Admission Test essay question are reported. Analyses focused on the performance characteristics of sample groups; the relationships between essay scores and academic/demographic characteristics; and the reliability of one 45-minute versus two 30-minute essays. (Author/MLW)

  19. Lincoln Era Essay Contest: Seventh Annual Winners, 1988.

    ERIC Educational Resources Information Center

    Cagle, William, Ed.

    The seventh annual Lincoln Era Essay Contest's theme was "Lincoln and the Elections of 1860 and 1864." The contest was open to students in grades 6 through 12 throughout the state of Indiana. This booklet includes all the winning essays. The junior high/middle school essays include: "Abraham Lincoln Journals for the 1860 and 1864…

  20. Comparison of Dimension Reduction Methods for Automated Essay Grading

    ERIC Educational Resources Information Center

    Kakkonen, Tuomo; Myller, Niko; Sutinen, Erkki; Timonen, Jari

    2008-01-01

    Automatic Essay Assessor (AEA) is a system that utilizes information retrieval techniques such as Latent Semantic Analysis (LSA), Probabilistic Latent Semantic Analysis (PLSA), and Latent Dirichlet Allocation (LDA) for automatic essay grading. The system uses learning materials and relatively few teacher-graded essays for calibrating the scoring…

  1. Rooted in the Land: Essays on Community and Place.

    ERIC Educational Resources Information Center

    Vitek, William, Ed.; Jackson, Wes, Ed.

    This collection of 31 essays examines the idea of community rooted in a particular place, usually a small town or rural place. Many essays comment on the role of education in promoting the transient materialistic lifestyle or suggest ways in which education could foster place attachment and community building. Essays specifically focused on…

  2. Conceptualizing Essay Tests' Reliability and Validity: From Research to Theory

    ERIC Educational Resources Information Center

    Badjadi, Nour El Imane

    2013-01-01

    The current paper on writing assessment surveys the literature on the reliability and validity of essay tests. The paper aims to examine the two concepts in relationship with essay testing as well as to provide a snapshot of the current understandings of the reliability and validity of essay tests as drawn in recent research studies. Bearing in…

  3. [New mammography technologies and their impact on radiation dose].

    PubMed

    Chevalier del Rio, M

    2013-12-01

    This article reviews new mammography technologies resulting from advances in digital detectors and processing techniques. Most are just starting to be commercialized or are in the clinical trial phase. The results of clinical trials with the new 2D techniques (contrast-enhanced techniques or stereotactic techniques) show they are useful for diagnosing cancer. However, the greater complexity of the image acquisition process suggests that their use will be limited to particular cases such as inconclusive lesions or women with high risk for developing breast cancer. Among the 3D technologies (breast tomography and breast tomosynthesis), only breast tomosynthesis has been implemented in clinical practice, so it is the only technique for which it is possible to know the sensitivity, specificity, and radiation dose delivered. This article describes the principles underlying the way breast tomosynthesis works and the techniques used for image acquisition and reconstruction. It also summarizes the main results obtained in clinical studies, which generally show that breast tomosynthesis increases the breast cancer detection rate while decreasing the recall rate and number of biopsies taken. The protocol for breast tomosynthesis approved by the Food and Drug Administration (USA) consists of two conventional mammography projections for each breast and two tomosynthesis projections for each breast. This means multiplying the risks of inducing cancer and death associated with 2D mammography by a factor between 2 and 3 (2.6-3.3 and 0.7-0.9 per 100,000 women exposed when 50 years old, respectively). The protocol for breast tomosynthesis examinations is one of the aspects that is essential to determine when including tomosynthesis in screening programs and routine breast imaging.

  4. Advantages of gridless full-field digital mammography

    NASA Astrophysics Data System (ADS)

    Nykanen, Kirsi; Siltanen, Samuli

    2003-06-01

    The purpose of the study was to find out whether the image quality in full-field digital mammography can be improved while lowering the patient dose by removing the anti-scatter grid. Moreover, a fast approximate computational algorithm was developed for determining the scattered field in a real mammogram. The method is non-iterative, robust against noise, and works without modification for any scatter-to-primary ratio. Furthermore, it is computationally effective since it is based on fast Fourier transform (FFT). It was found out that the wide dynamic range of digital detectors leads to decrease in patient dose from 10.9% up to 46.6% at breast thickness of 2cm and from 0.8% up to 40.8% at breast thickness of 4cm depending on the efficiency of the removed grid. At constant patient dose the increase in contrast-to-noise ratio is 5.8% - 36.9% and 0.4%-30.0% accordingly at those two breast thickness. The convolution-based X-ray scatter model was considered. The developed scatter removal method was demonstrated with simulated mammograms and applied to clinical full-field digital mammograms acquired with a high-end digital flat panel detector based on amorphous selenium. Errors in reconstructed scattered fields were 0.3% in case of an ideal simulated mammogram and 7.4% in case of a real simulated mammogram (3cm breast). Applications where the scattered field needs to be determined include 3-D mammography and dual-energy breast imaging. In screening mammography gray-scale optimization eliminates the effect of scattering.

  5. Validation of MTF measurement for digital mammography quality control

    SciTech Connect

    Carton, Ann-Katherine; Vandenbroucke, Dirk; Struye, Luc; Maidment, Andrew D.A.; Kao, Y.-H.; Albert, Michael; Bosmans, Hilde; Marchal, Guy

    2005-06-15

    The modulation transfer function (MTF) describes the spatial resolution properties of imaging systems. In this work, the accuracy of our implementation of the edge method for calculating the presampled MTF was examined. Synthetic edge images with known MTF were used as gold standards for determining the robustness of the edge method. These images simulated realistic data from clinical digital mammography systems, and contained intrinsic system factors that could affect the MTF accuracy, such as noise, scatter, and flat-field nonuniformities. Our algorithm is not influenced by detector dose variations for MTF accuracy up to 1/2 the sampling frequency. We investigated several methods for noise reduction, including truncating the supersampled line spread function (LSF), windowing the LSF, applying a local exponential fit to the LSF, and applying a monotonic constraint to the supersampled edge spread function. Only the monotonic constraint did not introduce a systematic error; the other methods could result in MTF underestimation. Overall, our edge method consistently computed MTFs which were in good agreement with the true MTF. The edge method was then applied to images from a commercial storage-phosphor based digital mammography system. The calculated MTF was affected by the size (sides of 2.5, 5, or 10 cm) and the composition (lead or tungsten) of the edge device. However, the effects on the MTF were observed only with regard to the low frequency drop (LFD). Scatter nonuniformity was dependent on edge size, and could lead to slight underestimation of LFD. Nevertheless, this negative effect could be minimized by using an edge of 5 cm or larger. An edge composed of lead is susceptible to L-fluorescence, which causes overestimation of the LFD. The results of this work are intended to underline the need for clear guidelines if the MTF is to be given a more crucial role in acceptance tests and routine assessment of digital mammography systems: the MTF algorithm and edge

  6. SU-E-I-88: Mammography Imaging: Does Positioning Matter?

    SciTech Connect

    Zhang, J; Szabunio, M

    2014-06-01

    Purpose: In mammography, compression is imperative for quality images and glandular radiation exposure dose. The thickness of the compressed breast directly determines mammography acquisition parameters. The compressed thickness varies due to variation in technologist practice, even for the same patient imaged at different time. This study is to investigate potential effect of the variation in breast positioning on radiation dose and image quality. Methods: Radiation dose at different thicknesses was measured with a BR-12 breast phantom for both conventional craniocaudal view and tomosynthesis in a Hologic Tomosynthesis mammography system. The CIRS stereotactic needle biopsy training phantom embedded dense masses and microcalcification in various sizes were imaged for image quality evaluation. Radiologists evaluated images. Clinical mammograms from the same patient but acquired at different time were retrospectively retrieved to evaluate potential effects of variation in positioning. Results: Acquisition parameters (kVp and mAs) increase with the increased phantom thickness. Radiation exposure increases following an exponential trend. The stereotactic phantom images showed loss of spatial and contrast resolution with inappropriate positioning. The compressed pressure may not be a good indicator for appropriate positioning. The inclusion of different amount of pectoralis muscle may lead to the same compressed pressure but different compressed thickness. The initial retrospective study of 3 patients showed that there were potential large variations in positioning the same patient at different examination time, resulting in large variations in patient radiation dose and image quality. Conclusion: Variations in patient positioning potentially influence patient radiation dose and image quality. The technologist has the critical responsibility to position patient to provide quality images in spite of different breast and body types. To reduce intra and inter practice

  7. Bone mineral imaging using a digital magnification mammography system

    NASA Astrophysics Data System (ADS)

    Toyofuku, Fukai; Tokumori, Kenji; Higashida, Yoshiharu; Arimura, Hidetaka; Morishita, Junji; Ohki, Masafumi

    2008-03-01

    The measurement of bone mineral content is important for diagnosis of demineralization diseases such as osteoporosis. A reliable method of obtaining bone mineral images using a digital magnification mammography system has been developed. The full-field digital phase contrast mammography (PCM) system, which has a molybdenum target of 0.1mm focal spot size, was used with 1.75 x magnification. We have performed several phantom experiments using aluminum step wedges (0.2 mm - 6.0 mm in thickness) and a bone mineral standard phantom composed of calcium carbonate and polyurethane (CaCO 3 concentration: 26.7 - 939.0 mg/cm 3) within a water or Lucite phantom. X-ray spectra on the exposure field are measured using a CdTe detector for evaluation of heel effect. From the equations of x-ray attenuation and the thickness of the subjects, quantitative images of both components were obtained. The quantitative images of the two components were obtained for different tube voltages of 24 kV to 39 kV. The relative accuracy was less than 2.5% for the entire aluminum thickness of 0.5 to 6.0 mm at 5 cm water thickness. Accuracy of bone mineral thickness was within 3.5% for 5cm water phantom. The magnified quantitative images of a hand phantom significantly increased the visibility of fine structures of bones. The digital magnification mammography system is useful not only for measurement of bone mineral content, but also high-resolution quantitative imaging of trabecular structure.

  8. Knowledge Discovery from Structured Mammography Reports Using Inductive Logic Programming

    PubMed Central

    Burnside, Elizabeth S.; Davis, Jesse; Costa, Vítor Santos; de Castro Dutra, Inês; Kahn, Charles E.; Fine, Jason; Page, David

    2005-01-01

    The development of large mammography databases provides an opportunity for knowledge discovery and data mining techniques to recognize patterns not previously appreciated. Using a database from a breast imaging practice containing patient risk factors, imaging findings, and biopsy results, we tested whether inductive logic programming (ILP) could discover interesting hypotheses that could subsequently be tested and validated. The ILP algorithm discovered two hypotheses from the data that were 1) judged as interesting by a subspecialty-trained mammographer and 2) validated by analysis of the data itself. PMID:16779009

  9. Volumetric lean percentage measurement using dual energy mammography

    PubMed Central

    Ducote, Justin L.; Klopfer, Michael J.; Molloi, S.

    2011-01-01

    Purpose: Currently, there is no accepted standard for measuring breast density. Dual energy mammography, which has demonstrated accurate measurement in phantoms, has been proposed as one possible method. To examine the use of chemical analysis as a possible means to validate breast density measurements from dual energy mammography, a bovine tissue model was investigated. Known quantities of lean and adipose tissue were compared with composition values measured from dual energy images and chemical analysis. Methods: Theoretical simulations were performed to assess the impact variations in breast composition would have on measurement of breast density from a single calibration. Fourteen ex-vivo tissue samples composed of varying amounts of pure lean tissue and pure adipose tissue (lean percentage) from 0 to 100%, in increments of 10%, were imaged using dual energy mammography. This was followed by chemical analysis based on desiccation, trituration, and fat extraction with petroleum ether to determine water, lipid, and protein content. The volumetric lean percentage (VLP) as measured from images (VLPI) and as derived from chemical analysis data (VLPCA) were compared with the VLP calculated from measurements of sample mass with a scale (VLPM). Finally, data from the bovine tissue model in this study were compared to compositional data from a previous report of human tissue composition. Results: The results from simulation suggest a substantial impact on measuring breast density is likely due to changes in anatomical breast composition. VLPI was related to the VLPM by VLPI = 1.53 VLPM + 10.0 (r2>0.99). VLPCA was related to VLPM by VLPCA = 0.76 VLPM + 22.8 (r2>0.99). VLPI was related to VLPCA by VLPI = 2.00 VLPCA − 35.6 (r2>0.99). Bovine adipose tissue was shown to be very similar to human adipose tissue in terms of water, lipid, and protein content with RMS differences of 1.2%. Bovine lean tissue was shown to be very similar to human skeletal

  10. Digital Mammography with a Mosaic of CCD Arrays

    NASA Technical Reports Server (NTRS)

    Jalink, Antony, Jr. (Inventor); McAdoo, James A. (Inventor)

    1998-01-01

    A digital mammography device uses a mosaic of electronic digital imaging arrays to scan an x-ray image is discussed. The mosaic of arrays is repositioned several times to expose different portions of the image, until the entire image is scanned. The data generated by the arrays during each exposure is stored in a computer. After the final exposure, the computer combines data of the several partial images to produce a composite of the original x-ray image. An aperture plate is used to reduce scatter and the overall exposure of the patient to x-rays.

  11. Nuclear winter: the continuing debate. Student essay

    SciTech Connect

    Nida, A.V.

    1987-03-23

    This essay examines the debate over the climatic consequences of global nuclear war as related in the so-called Nuclear Winter hypothesis. This review examines the major components of the theory and traces development of the scientific knowledge leading to a second phase of the controversy two years after the first hypothesis. The conclusions of the essay are that the original nuclear winter findings have been altered by later scientific study and, therefore, the political conclusions drawn by Carl Sagan in 1983 can no longer be supported by theory or facts. Continued use of the Crutzen-Birks (Ambio, 1982) and TTAPS (Science, December 1983) studies worst-case evidence from NCAR (Foreign Affairs, Summer 86) represents selective science. Arguing for strategic policy changes based on nuclear winter risks constitutes anti-nuclear rhetoric and not scientific reasoning.

  12. [Essay on the myth of oedipus].

    PubMed

    Costa, Néstor E

    2012-01-01

    Jung conceptualized the collective unconscious as the locus of the myths, the absolutely genuine and primary patterns of thinking and feeling of humanity. The legend of Oedipus or myth of incest is a irrefutable proof of its eternal validity. The present essay is an attempt to take an alternative look to a history that belong to all of us. Situations that are developed in this drama, like the characters involved in it may charge significance as an archetypal and essentially symbolic interpretation.

  13. Essays in renewable energy and emissions trading

    NASA Astrophysics Data System (ADS)

    Kneifel, Joshua D.

    Environmental issues have become a key political issue over the past forty years and has resulted in the enactment of many different environmental policies. The three essays in this dissertation add to the literature of renewable energy policies and sulfur dioxide emissions trading. The first essay ascertains which state policies are accelerating deployment of non-hydropower renewable electricity generation capacity into a states electric power industry. As would be expected, policies that lead to significant increases in actual renewable capacity in that state either set a Renewables Portfolio Standard with a certain level of required renewable capacity or use Clean Energy Funds to directly fund utility-scale renewable capacity construction. A surprising result is that Required Green Power Options, a policy that merely requires all utilities in a state to offer the option for consumers to purchase renewable energy at a premium rate, has a sizable impact on non-hydro renewable capacity in that state. The second essay studies the theoretical impacts fuel contract constraints have on an electricity generating unit's compliance costs of meeting the emissions compliance restrictions set by Phase I of the Title IV SO2 Emissions Trading Program. Fuel contract constraints restrict a utility's degrees of freedom in coal purchasing options, which can lead to the use of a more expensive compliance option and higher compliance costs. The third essay analytically and empirically shows how fuel contract constraints impact the emissions allowance market and total electric power industry compliance costs. This paper uses generating unit-level simulations to replicate results from previous studies and show that fuel contracts appear to explain a large portion (65%) of the previously unexplained compliance cost simulations. Also, my study considers a more appropriate plant-level decisions for compliance choices by analytically analyzing the plant level decision-making process to

  14. A Topic-Independent Method for Scoring Student Essay Content

    NASA Astrophysics Data System (ADS)

    Nagata, Ryo; Kakegawa, Jun-Ichi; Yabuta, Yukiko

    This paper proposes a topic-independent method for automatically scoring essay content. Unlike conventional topic-dependent methods, it predicts the human-assigned score of a given essay without training essays written to the same topic as the target essay. To achieve this, this paper introduces a new measure called MIDF that measures how important and relevant a word is in a given essay. The proposed method predicts the score relying on the distribution of MIDF. Surprisingly, experiments show that the proposed method achieves an accuracy of 0.848 and performs as well as or even better than conventional topic-dependent methods.

  15. Comparison of 2D versus 3D mammography with screening cases: an observer study

    NASA Astrophysics Data System (ADS)

    Fernandez, James Reza; Deshpande, Ruchi; Hovanessian-Larsen, Linda; Liu, Brent

    2012-02-01

    Breast cancer is the most common type of non-skin cancer in women. 2D mammography is a screening tool to aid in the early detection of breast cancer, but has diagnostic limitations of overlapping tissues, especially in dense breasts. 3D mammography has the potential to improve detection outcomes by increasing specificity, and a new 3D screening tool with a 3D display for mammography aims to improve performance and efficiency as compared to 2D mammography. An observer study using human studies collected from was performed to compare traditional 2D mammography with this new 3D mammography technique. A prior study using a mammography phantom revealed no difference in calcification detection, but improved mass detection in 2D as compared to 3D. There was a significant decrease in reading time for masses, calcifications, and normals in 3D compared to 2D, however, as well as more favorable confidence levels in reading normal cases. Data for this current study is currently being obtained, and a full report should be available in the next few weeks.

  16. Essays on environmental policies, corruption, and energy

    NASA Astrophysics Data System (ADS)

    Baksi, Soham

    This thesis consists of four essays. The first essay looks at pollution taxation under capital mobility, and analyzes the role of pre-commitment by countries to their pollution tax rate. A polluting firm sells its product in two countries, and can locate and produce in a single country or in both countries. Due to the discrete-choice nature of the firm's location problem, the countries' welfare functions are discontinuous in their pollution tax rate. We show that when the countries cannot pre-commit to their pollution tax, the firm can still engender tax competition between them by strategically locating in both the countries. Moreover, pre-commitment pollution taxation may not be welfare improving for the countries, although it always makes the firm better off. The second essay studies the effect of liberalization on corruption. Corruptible inspectors enforce an environmental regulation on firms, and are monitored by an honest regulator. Liberalization not only increases the variety of goods and the marginal utility of accepting a bribe, but also puts pressure on the regulator to curb corruption. The interaction of these two effects can cause corruption to initially increase with liberalization, and then decrease beyond a threshold. Moreover, equilibrium corruption is lower when the regulator is able to pre-commit to her monitoring frequency. The third essay analyzes optimal labeling (information revelation) procedures for hidden attributes of credence goods. Consumers are heterogeneous in their preference for the hidden attribute, and producers can either self-label their products, or have them certified by a third party. The government can impose self or third-party labeling requirements on either the "green" or the "brown" producers. When corrupt producers can affix spurious labels, the government needs to monitor them. A mandatory self-labeling policy is shown to generally dominate mandatory third-party labeling. The fourth essay develops formulas for

  17. Three essays on energy efficiency policy

    NASA Astrophysics Data System (ADS)

    Kabiri, Maryam

    This thesis is comprised of three essays which explore selected aspects of demand side energy efficiency policy of International Energy Conservation Codes (IECC). The first essay models the adoption of IECC in the U.S. between 1998 and 2010. An ordered probit model with IECC adoption as the dependent variable is used to test if a set of socio-economics, political, spatial, and environmental factors predict the residential building energy code adoption. The results show that higher energy price, relative political extraction, climate extremes, pollution level, and population growth predict IECC adoption in the sample. The diffusion variable (share of neighbor states with IECC) is shown to have large impacts on the probability of IECC adoption. The next two essays examine the effect of IECC on residential electricity consumption. The second essay investigates the impact of International Energy Conservation Codes (IECC) on per-capita residential electricity consumption for 44 U.S. states from 1981-2008. Applying the pooled mean group (PMG) model developed by Pesaran et al. (1999), and controlling for energy specific demand factors such as: prices, income, heating degree days, and cooling degree days, I find that there is an overall 2% decrease in new residential buildings per-capita electricity consumption in the states which adopted any version of IECC. The new residential buildings per-capita electricity consumption has decreased by about 2.5% and 5% in the states with IECC 2000 and IECC 2003 respectively. The third essay examines the impact of building energy code on the household electricity consumption in three states in U.S. To do so; I construct a pseudo panel using household level data from the American Community Survey (ACS) over the period 2005-2010. By constructing pseudo panel, we are able to track cohorts of relatively homogeneous individuals over time, and control for cohort unobserved heterogeneity that may bias the results of cross sectional estimates

  18. Dosimetry in Mammography: Average Glandular Dose Based on Homogeneous Phantom

    NASA Astrophysics Data System (ADS)

    Benevides, Luis A.; Hintenlang, David E.

    2011-05-01

    The objective of this study was to demonstrate that a clinical dosimetry protocol that utilizes a dosimetric breast phantom series based on population anthropometric measurements can reliably predict the average glandular dose (AGD) imparted to the patient during a routine screening mammogram. AGD was calculated using entrance skin exposure and dose conversion factors based on fibroglandular content, compressed breast thickness, mammography unit parameters and modifying parameters for homogeneous phantom (phantom factor), compressed breast lateral dimensions (volume factor) and anatomical features (anatomical factor). The patient fibroglandular content was evaluated using a calibrated modified breast tissue equivalent homogeneous phantom series (BRTES-MOD) designed from anthropomorphic measurements of a screening mammography population and whose elemental composition was referenced to International Commission on Radiation Units and Measurements Report 44 and 46 tissues. The patient fibroglandular content, compressed breast thickness along with unit parameters and spectrum half-value layer were used to derive the currently used dose conversion factor (DgN). The study showed that the use of a homogeneous phantom, patient compressed breast lateral dimensions and patient anatomical features can affect AGD by as much as 12%, 3% and 1%, respectively. The protocol was found to be superior to existing methodologies. The clinical dosimetry protocol developed in this study can reliably predict the AGD imparted to an individual patient during a routine screening mammogram.

  19. Dosimetry in Mammography: Average Glandular Dose Based on Homogeneous Phantom

    SciTech Connect

    Benevides, Luis A.; Hintenlang, David E.

    2011-05-05

    The objective of this study was to demonstrate that a clinical dosimetry protocol that utilizes a dosimetric breast phantom series based on population anthropometric measurements can reliably predict the average glandular dose (AGD) imparted to the patient during a routine screening mammogram. AGD was calculated using entrance skin exposure and dose conversion factors based on fibroglandular content, compressed breast thickness, mammography unit parameters and modifying parameters for homogeneous phantom (phantom factor), compressed breast lateral dimensions (volume factor) and anatomical features (anatomical factor). The patient fibroglandular content was evaluated using a calibrated modified breast tissue equivalent homogeneous phantom series (BRTES-MOD) designed from anthropomorphic measurements of a screening mammography population and whose elemental composition was referenced to International Commission on Radiation Units and Measurements Report 44 and 46 tissues. The patient fibroglandular content, compressed breast thickness along with unit parameters and spectrum half-value layer were used to derive the currently used dose conversion factor (DgN). The study showed that the use of a homogeneous phantom, patient compressed breast lateral dimensions and patient anatomical features can affect AGD by as much as 12%, 3% and 1%, respectively. The protocol was found to be superior to existing methodologies. The clinical dosimetry protocol developed in this study can reliably predict the AGD imparted to an individual patient during a routine screening mammogram.

  20. Frequency-domain optical mammography: edge effect corrections.

    PubMed

    Fantini, S; Franceschini, M A; Gaida, G; Gratton, E; Jess, H; Mantulin, W W; Moesta, K T; Schlag, P M; Kaschke, M

    1996-01-01

    We have investigated the problem of edge effects in laser-beam transillumination scanning of the human breast. Edge effects arise from tissue thickness variability along the scanned area, and from lateral photon losses through the sides of the breast. Edge effects can be effectively corrected in frequency-domain measurements by employing a two-step procedure: (1) use of the phase information to calculate an effective tissue thickness for each pixel location; (2) application of the knowledge of tissue thickness to calculate an edge-corrected optical image from the ac signal image. The measurements were conducted with a light mammography apparatus (LIMA) designed for feasibility tests in the clinical environment. Operating in the frequency-domain (110 MHz), this instrument performs a transillumination optical scan at two wavelengths (685 and 825 nm). We applied the proposed two-step procedure to data from breast phantoms and from human breasts. The processed images provide higher contrast and detectability in optical mammography with respect to raw data breast images.

  1. Breast screening with mammography: Overview of Swedish randomized trials

    SciTech Connect

    Nystroem, L.; Wall, S. . Dept. of Epidemiology and Public Health); Rutqvist, L.E. . Oncologic Centre); Lindgren, A. ); Lindqvist, M. ); Ryden, S. ); Andersson, J. ); Bjurstam, N. ); Fagerberg, G. ); Frisell, J. ); Tabar, L. ); Larson, L.G. . Oncologic Centre)

    1993-04-17

    Despite encouraging results from screening trials the efficacy of mammography in reducing mortality remains somewhat controversial. Five studies have been done in Sweden. This overview, reveals a 24% significant reduction of breast cancer mortality among those invited to mammography screening compared with those not invited. To avoid the potential risk of differential misclassification causes of death were assessed by an independent end-point committee after a blinded review of all fatal breast cancer cases. The mortality reduction was similar, irrespective of the end-point used for evaluation (breast cancer as underlying cause of death or breast cancer present at death). There was a consistent risk reduction associated with screening in all studies, although the point estimate of the relative risk for all ages varied non-significantly between 0.68 and 0.84. The cumulative breast cancer mortality by time since randomization was estimated at 1.3 per 1,000 within 6 years in the invited group compared with 1.6 in the control group. The corresponding figures after 9 years are 2.6 and 3.3 and after 12 years 3.9 and 5.1.

  2. Performance characterization of computed radiography based mammography systems

    NASA Astrophysics Data System (ADS)

    Singh, Abhinav; Desai, Nikunj; Valentino, Daniel J.

    2010-04-01

    Computed Radiography (CR) is a cost-effective technology for digital mammography. In order to optimize the quality of images obtained using CR Mammography, we characterized the effect on image quality of the electrooptical components of the CR imaging chain. The metrics used to assess the image quality included the Contrast to Noise Ratio (CNR), Modulation Transfer Function (MTF), Noise Power Spectrum (NPS), Detective Quantum Efficiency (DQE) and Contrast Detail Response Phantom (CDMAM 3.4 Artinis Medical Systems). An 18×24 cm high-resolution granular phosphor imaging plate (AGFA MM3.0) was used to acquire the images. Contrast detail was measured using a GUI developed for the CDMAM phantom that was scored by independent observers. The range of theoretically acceptable values measured for the CR laser was (5-36) mW and voltage range for PMT's was (4-8) V. The light detection amplifier was investigated, and the optimal Laser Power and PMT gain used for scanning was measured. The tools that we used (CNR, MTF, NPS, DQE and Contrast-detail phantom) provided an effective means of selecting optimal values for the electro-optical components of the system. The procedure enabled us to obtain good quality CR mammograms that have less noise and improved contrast.

  3. Predicting contrast detail performance from objective measurements in digital mammography

    NASA Astrophysics Data System (ADS)

    Young, Kenneth C.; Alsager, Abdulaziz; Dance, David R.; Oduko, Jennifer M.; Gundogdu, Ozcan; Spyrou, Nicholas M.

    2009-02-01

    European Guidelines for quality control in digital mammography specify minimum and achievable standards of image quality in terms of threshold contrast, based on readings of images of the CDMAM test object by human observers. However the methodology is time-consuming and has large inter- and intra-observer error. To overcome these problems a software program is available to automatically read CDMAM images. An alternative approach would be to predict threshold contrast from measurements of DQE and MTF using a model of the imaging process. A simple signal-matched noise-integration model has been used to predict the contrast detail response of five different types of commercial digital mammography system (Siemens Inspiration, GE Senographe DS, and three types of Konica Minolta computerised radiography system). Measurements were made of the MTF and DQE of each detector and the noise equivalent apertures calculated. For each system sets of 16 images of the CDMAM test object were acquired at a range of dose levels and contrast-detail plots obtained using human observers and automated reading. The theoretically and experimentally determined threshold contrasts were compared. An encouragingly good level of agreement was found between the experimental data and theoretical predictions.

  4. Diagnostic criteria for mass lesions differentiating in electrical impedance mammography

    NASA Astrophysics Data System (ADS)

    A, Karpov; M, Korotkova

    2013-04-01

    The purpose of this research was to determine the diagnostic criteria for differentiating volumetric lesions in the mammary gland in electrical impedance mammography. The research was carried out utilizing the electrical impedance computer mammograph llMEIK v.5.6gg®, which enables to acquire images of 3-D conductivity distribution layers within mamma's tissues up to 5 cm depth. The weighted reciprocal projection method was employed to reconstruct the 3-D electric conductivity distribution of the examined organ. The results of 3,710 electrical impedance examinations were analyzed. The analysis of a volumetric lesion included assessment of its shape, contour, internal electrical structure and changes of the surrounding tissues. Moreover, mammary gland status was evaluated with the help of comparative and age-related electrical conductivity curves. The diagnostic chart is provided. Each criterion is measured in points. Using the numerical score for evaluation of mass and non-volumetric lesions within the mammary gland in electrical impedance mammography allowed comparing this information to BI-RADS categories developed by American College of Radiology experts. The article is illustrated with electrical impedance mammograms and tables.

  5. Using physician correspondence and postcard reminders to promote mammography use.

    PubMed Central

    Taplin, S H; Anderman, C; Grothaus, L; Curry, S; Montano, D

    1994-01-01

    OBJECTIVES. In a health maintenance organization that mails letters to women recommending that they schedule mammograms, we conducted a randomized trial to evaluate simple methods of increasing the use of screening mammography. METHODS. Using a 2 x 2 factorial design, we tested the effects of (1) mailing the recommendation letter from each woman's primary care physician rather than from the program director and (2) sending a subsequent reminder postcard. RESULTS. Sending a reminder postcard nearly doubled the odds that women would get mammograms within 1 year (participate). The letter from the woman's personal physician had no effect. Attending a clinic more than 45 minutes from the screening center, being a current smoker, or being in fair or poor health were negatively associated with subsequently obtaining a mammogram. The odds of participation doubled if women had had previous mammograms. CONCLUSIONS. When preceded by written recommendations to schedule mammograms, reminder postcards effectively increased participation. Future randomized trials to promote use of screening mammography should compare interventions with a reminder condition. PMID:8154558

  6. Multistrategy health education program to increase mammography use among women ages 65 and older.

    PubMed Central

    Rimer, B K; Resch, N; King, E; Ross, E; Lerman, C; Boyce, A; Kessler, H; Engstrom, P F

    1992-01-01

    Mammography use decreases with age although the risk of breast cancer increases with age. Medicare now provides biennial coverage for screening mammography. This study was designed to simulate the Medicare condition by subsidizing mammography among women in eight retirement communities in the metropolitan Philadelphia area. The study also measured the impact of health education interventions and the presence of a mobile mammography van on increased use of mammography. Retirement communities were assigned randomly to the control (cost subsidy alone) or experimental group (cost subsidy, mammography van, and tailored health education interventions). A total of 412 women ages 65 and older who had not had mammograms in the previous year were surveyed at baseline and 3 months later. Analytic techniques reflected the cluster nature of the randomization. Women in the experimental group were significantly more likely than the control group women to have obtained mammograms. Forty-five percent of the experimental group women compared with 12 percent of the control group women subsequently had mammograms in the 3 months after the baseline interview (P less than .001). Logistic regression analysis for mammography use indicated an odds ratio of 6.1 associated with being in the experimental group. For women in the experimental group, a separate logistic regression for mammography use showed an odds ratio of 7.8 associated with attendance at the educational presentation. The results suggest that Medicare coverage alone will not increase mammography use sufficiently to achieve year 2000 objectives. However, the addition of access enhancing and health education interventions boosts utilization dramatically. PMID:1641432

  7. Characterization of scatter in digital mammography from physical measurements

    SciTech Connect

    Leon, Stephanie M. Wagner, Louis K.; Brateman, Libby F.

    2014-06-15

    Purpose: That scattered radiation negatively impacts the quality of medical radiographic imaging is well known. In mammography, even slight amounts of scatter reduce the high contrast required for subtle soft-tissue imaging. In current clinical mammography, image contrast is partially improved by use of an antiscatter grid. This form of scatter rejection comes with a sizeable dose penalty related to the concomitant elimination of valuable primary radiation. Digital mammography allows the use of image processing as a method of scatter correction that might avoid effects that negatively impact primary radiation, while potentially providing more contrast improvement than is currently possible with a grid. For this approach to be feasible, a detailed characterization of the scatter is needed. Previous research has modeled scatter as a constant background that serves as a DC bias across the imaging surface. The goal of this study was to provide a more substantive data set for characterizing the spatially-variant features of scatter radiation at the image detector of modern mammography units. Methods: This data set was acquired from a model of the radiation beam as a matrix of very narrow rays or pencil beams. As each pencil beam penetrates tissue, the pencil widens in a predictable manner due to the production of scatter. The resultant spreading of the pencil beam at the detector surface can be characterized by two parameters: mean radial extent (MRE) and scatter fraction (SF). The SF and MRE were calculated from measurements obtained using the beam stop method. Two digital mammography units were utilized, and the SF and MRE were found as functions of target, filter, tube potential, phantom thickness, and presence or absence of a grid. These values were then used to generate general equations allowing the SF and MRE to be calculated for any combination of the above parameters. Results: With a grid, the SF ranged from a minimum of about 0.05 to a maximum of about 0

  8. Assessing the Potential Effectiveness of Pictorial Messages to Deter Young Women from Indoor Tanning: An Experimental Study.

    PubMed

    Sontag, Jennah M; Noar, Seth M

    2017-03-07

    The recent Surgeon General's call-to-action to prevent skin cancer indicates an urgent need for research on messages to deter young women from tanning indoors. Answering this call, the current study assessed differences in the potential effectiveness of pictorial indoor tanning messages. We randomly assigned undergraduate female participants (N = 568) to one of three message conditions visually depicting health effects, appearance damage, or immediate risks, or to a text-only control. All participants viewed three messages within their condition and answered questions after message exposure. Factorial ANOVAs indicated that compared to the text-only condition, pictorial messages produced greater negative emotional reactions and were perceived as more effective than text-only messages. Text-only messages, however, were significantly more believable than pictorial messages. We observed several differences among the pictorial conditions and among the messages within the pictorial conditions. We conclude that messages discouraging indoor tanning should use pictorial messages illustrating the negative health and appearance damaging effects of indoor tanning, focusing on particular health and appearance consequences. Additional research is needed to guide the selection of images that are believable and will most discourage indoor tanning behavior.

  9. Automatic patient dose registry and clinical audit on line for mammography.

    PubMed

    Ten, J I; Vano, E; Sánchez, R; Fernandez-Soto, J M

    2015-07-01

    The use of automatic registry systems for patient dose in digital mammography allows clinical audit and patient dose analysis of the whole sample of individual mammography exposures while fulfilling the requirements of the European Directives and other international recommendations. Further parameters associated with radiation exposure (tube voltage, X-ray tube output and HVL values for different kVp and target/filter combinations, breast compression, etc.) should be periodically verified and used to evaluate patient doses. This study presents an experience in routine clinical practice for mammography using automatic systems.

  10. Primary Non-Hodgkin Lymphoma of the Breast: Ultrasonography, Elastography, Digital Mammography, Contrast-Enhanced Digital Mammography, and Pathology Findings.

    PubMed

    Gkali, Christina An; Chalazonitis, Athanasios N; Feida, Eleni; Giannos, Aris; Sotiropoulou, Maria; Dimitrakakis, Constantine; Loutradis, Dimitrios

    2015-12-01

    Lymphomas constitute approximately 0.15% of malignant mammary neoplasms. Less than 0.5% of all malignant lymphomas involve the breast primarily. Primary non-Hodgkin breast lymphoma is usually right sided. The combined therapy approach, with chemotherapy and radiotherapy, is the most successful treatment. Mastectomy offers no benefit in the treatment of primary non-Hodgkin breast lymphoma. To the author's knowledge, this is the first published case of primary non-Hodgkin breast lymphoma reported with conventional ultrasonography, elastography (both freehand and acoustic radiation force impulse imaging), digital mammography, contrast-enhanced digital mammography, and pathology findings. A 45-year-old woman presented with a lump in the right breast for 2 months. There was no evidence of systemic lymphoma or leukemia when the breast lesion was detected. Imaging findings were negative for lymphoma. Ipsilateral lymph nodes were not palpable. The mass was resected, and histopathology findings were diagnostic of non-Hodgkin lymphoma. Immunohistochemistry was confirmatory of non-Hodgkin lymphoma, diffuse large cell type of B-cell lineage. Although primary and secondary lymphomas of the breast are rare entities, they should be considered in the differential diagnosis of breast malignancies.

  11. Initial Validation of a Brief Pictorial Measure of Caregiver Aggression: The Family Aggression Screening Tool.

    PubMed

    Cecil, Charlotte A M; McCrory, Eamon J; Viding, Essi; Holden, George W; Barker, Edward D

    2016-06-01

    In the present study, we report on the development and initial psychometric properties of the Family Aggression Screening Tool (FAST). The FAST is a brief, self-report tool that makes use of pictorial representations to assess experiences of caregiver aggression, including direct victimization and exposure to intimate partner violence. It is freely available on request and takes under 5 minutes to complete. Psychometric properties of the FAST were investigated in a sample of 168 high-risk youth aged 16 to 24 years. For validation purposes, maltreatment history was assessed using the Childhood Trauma Questionnaire; levels of current psychiatric symptoms were also assessed. Internal consistency of the FAST was good. Convergent validity was supported by strong and discriminative associations with corresponding Childhood Trauma Questionnaire subscales. The FAST also correlated significantly with multi-informant reports of psychiatric symptomatology. Initial findings provide support for the reliability and validity of the FAST as a brief, pictorial screening tool of caregiver aggression.

  12. Words or Pictures: A comparison of written and pictorial explanations of physical and chemical equilibria

    NASA Astrophysics Data System (ADS)

    Akaygun, Sevil; Jones, Loretta L.

    2014-03-01

    The features of a concept or principle an individual chooses to highlight in an explanation or description may be related to the medium of communication used. Different aspects of understanding can be revealed through words and through drawings. This two-part exploratory study examined the differences between explanations of physical and chemical equilibria generated by means of words or pictures. Participants included both instructors and students, who were randomly assigned to provide either written explanations or drawings of physical or chemical equilibrium at the macroscopic and particulate levels. For both studies, analyses revealed that significantly different features appeared in the written and pictorial explanations of equilibrium. The written responses focused more on processes such as the dynamic nature of equilibrium, whereas pictorial representations highlighted structural aspects of equilibrium, such as the spatial arrangement of molecules. Regardless of the level of chemistry knowledge, people conveyed the same type of information via the use of different representations and visual tools.

  13. The Influence of Emotional State and Pictorial Cues on Perceptual Judgments

    SciTech Connect

    Kimberly R. Raddatz; Abigail Werth; Tuan Q. Tran

    2007-10-01

    Perspective displays (e.g., CDTI) are commonly used as decision aids in environments characterized by periods of high emotional arousal (e.g., terrain enhanced primary flight displays). However, little attention has been devoted to understanding how emotional state, independently or in conjunction with other perceptual factors (e.g., pictorial depth cues), can impact perceptual judgments. Preliminary research suggests that induced emotional state (positive or negative) adversely impacts size comparisons in perspective displays (Tran & Raddatz, 2006). This study further investigated how size comparisons are affected by emotional state and pictorial depth cues while attenuating the limitations of the Tran & Raddatz (2006) study. Results confirmed that observers do make slower judgments under induced emotional state. However, observers under negative emotional state showed higher sensitivity (d’) and required more evidence to respond that a size difference exists (response bias) than observers under positive emotional state. Implications for display design and human performance are discussed.

  14. Three essays on "making" electric power markets

    NASA Astrophysics Data System (ADS)

    Kench, Brian Thomas

    2000-10-01

    Technological change over the past three decades has altered most of the basic conditions in the electric power industry. Because of technical progress, the dominant paradigm has shifted from the provision of electric power by regulated and vertically integrated local natural monopolies to competition and vertical separation. In the first essay I provide a historical context of the electric industry's power current deregulation debate. Then a dynamic model of induced institutional change is used to investigate how endogenous technological advancements have induced radical institutional change in the generation and transmission segments of the electric power industry. Because the Federal Energy Regulatory Commission (FERC) ordered regulated utilities to provide open access to their transmission networks and to separate their generation and transmission functions, transmission networks have been used more intensively and in much different ways then in the past. The second essay tests experimentally the predictions of neoclassical theory for a radial electric power market under two alternative deregulated transmission institutions: financial transmission rights and physical transmission rights. Experimental evidence presented there demonstrates that an electric power market with physical transmission rights governing its transmission network generates more "right" market signals relative to a transmission network governed by financial transmission rights. The move to a greater reliance on markets for electric power is an idea that has animated sweeping and dramatic changes in the traditional business of electric power. The third essay examines two of the most innovative and complex initiatives of making electric power markets in the United States: California and PJM. As those markets mature and others are made, they must revise their governance mechanisms to eliminate rules that create inefficiency and adopt rules that work efficiently elsewhere. I argue that

  15. Exocomet Circumstellar Fe I Absorption in the Beta Pictoris Gas Disk

    NASA Astrophysics Data System (ADS)

    Welsh, Barry Y.; Montgomery, Sharon

    2016-06-01

    We present an archival study of 27 circumstellar Fe i (λ3860 Å) and Ca ii (λ3933 Å) absorption spectra of the β Pictoris system recorded over the 2003-2014 timeframe. We have detected several transient absorption events at velocities red-shifted by >+20 km s-1 from the main central absorption line profiles of both Fe i and Ca ii. Such events can be attributed to the presence of kilometer-sized infalling evaporating bodies (i.e., exocomets) on their grazing approach to the central star. The majority of the transient absorption events detected in the Fe i profiles occur at velocities in the +35 to +50 km s-1 range. This is consistent with that found for Ca ii gas that has been sublimated from the “D” family of β Pictoris exocomets recently found by Kiefer et al. These spectra also reveal that the strength of the main component of the Fe i absorption line at V helio ˜ +21 km s-1 has weakened by ˜30% since 2011. Since neutrals, when ionized, are the main source of the ion-braking mechanism of Brandeker for circumstellar gas in the β Pictoris system, then this may have some measurable effect on the size and/or location of the main circumstellar gas disk. Finally we note that we have failed to detect any circumstellar Fe i absorption in our previously reported spectra of similar gas disks surrounding 28 young A-type stars. Thus, it would appear that the β Pictoris is anomalous with regards to circumstellar Fe i absorption.

  16. MRI of the stomach: a pictorial review with a focus on oncological applications and gastric motility.

    PubMed

    Sheybani, Arman; Menias, Christine O; Luna, Antonio; Fowler, Kathryn J; Hara, Amy Kiyo; Silva, Alvin C; Yano, Motoyo; Sandrasegaran, Kumar

    2015-04-01

    The purpose of this pictorial review is to demonstrate gastric pathology seen on magnetic resonance imaging (MRI) and discuss the essential MRI sequences for the evaluation of benign and malignant gastric pathologies. Common tumors of the stomach, polyposis syndromes, iatrogenic conditions, as well as other conditions of the stomach will be reviewed. The utility of MRI in the evaluation of patients with gastric malignancies and disorders of gastric motility will also be discussed.

  17. Framing Pictorial Cigarette Warning Labels to Motivate Young Smokers to Quit

    PubMed Central

    Turner, Monique M.; Zhao, Xiaoquan; Evans, W. Douglas; Luta, George; Tercyak, Kenneth P.

    2015-01-01

    Introduction: The Family Smoking Prevention and Tobacco Control Act requires new pictorial warnings for U.S. cigarette packs, but enactment has been delayed by tobacco industry lawsuits. Research can inform implementation of the pictorial warning requirement and identify ways to optimize their public health impact post-implementation. This study investigated the impact of warning label message framing on young smokers’ motivation to quit, examining cessation self-efficacy, and perceived risks as moderators of message framing impact. Methods: Smokers ages 18–30 (n = 740) completed baseline measures and were randomized to view 4 images of cigarette packs with pictorial health warnings featuring gain- or loss-framed messages. Motivation to quit was assessed after participants viewed the pack images. Linear models accounting for repeated measures and adjusting for baseline covariates examined the impact of message framing and interactions with baseline self-efficacy to quit and perceived risks of smoking. Results: Loss-framed warnings prompted significantly greater motivation to quit among smokers with high self-efficacy compared with smokers with low self-efficacy. Among smokers with low self-efficacy, gain-framed messages were superior to loss-framed messages. Gain-framed warnings generated significantly greater motivation to quit among smokers with high perceived risks compared with smokers with low perceived risks. Among smokers with high perceived risks, gain-framed messages were superior to loss-framed messages. Conclusions: A combination of pictorial warnings featuring risk-based (i.e., loss-framed) and efficacy-enhancing (i.e., gain-framed) information may promote better public health outcomes. Research is needed to investigate how strategically framed warning messages impact smokers’ behaviors based on their pre-existing attitudes and beliefs in real-world settings. PMID:25143295

  18. A Comparison of Pictorial and Speech Warning Messages in the Modern Cockpit.

    DTIC Science & Technology

    1984-12-01

    therefore had to include an extra translation step in processing information presented in that mode. While many might argue that it is important to... translate the pictorial spatial information into serial information before searching for the correct response. The indirect mapping of the pictures...spatial translation ), then greater compatibility is achieved when the information is presented in the verbal format as opposed to a spatial format. While

  19. Effective Presentation Media for Passenger Safety I: Comprehension of Briefing Card Pictorials and Pictograms

    DTIC Science & Technology

    2008-09-01

    Results indicate that safety briefing card pictorials/pictograms need to be designed and implemented with respect to novice passengers who do not have a...prepotent understanding of the design and operation of transport aircraft, emergency equipment, and/or aircraft emergency procedures. Furthermore...such as “fasten seat belts, no smokng n the lavatory, move handle n drecton of arrow, open door, place head between legs, and use seat cushon

  20. Epilepsy, hysteria, and "possession". A historical essay.

    PubMed

    Glaser, G H

    1978-04-01

    A historical essay is presented relating concepts of epilepsy, hysteria, and "possession." The designation "hysteroepilepsy" is placed into the context of combined phenomena in individual subject instances. An association of psychotic states resembling a schizoprenic disorder is indicated as occurring in certain epileptic patients, especially some complex partial seizures (i.e., temporal lobe-psychomotor type). Phenomena of possession may appear within any of these entities. Differential diagnosis now is aided greatly by ulilization of monitoring with combined split screen television viewing and recording of the patient's behavior and the concomitant electroencephalogram. Treatment is directed both medically and toward alleviation of contributing and precipitating psychological and sociological factors.

  1. Essays on environmental and energy economics

    NASA Astrophysics Data System (ADS)

    Brucal, Arlan Zandro

    This dissertation applies techniques from the expanding field of econometrics to the study of contemporary issues in environmental and resource economics. Three essays are offered that aim to generate meaningful policy implications through econometric analyses of the voluminous data recently becoming available to researchers. The first essay examines how overall price, quality and welfare changed as energy efficiency standards in the US became progressively more stringent between 2001-2011. A novel index-the Constant Quality Price Index (CQPI)-is developed to delineate changes in overall price and quality. Results obtained using point-of-sale data from individual clothes washers sold in the US during the period suggest that standards on washing machines have had at worst a negligible effect on consumer welfare, or at best lowered prices and improved quality for washers. The second essay analyzes the relationship between foreign acquisition and aspects of plant-level environmental performance using micro data from the Indonesian Census of Manufacturing. To establish a causal effect of ownership change, a difference-in-differences approach is combined with coarsened exact matching. A total of 264 acquisition cases between 1983-2001 are considered, where an acquired plant is observed at least a year before and three years after undergoing a change in ownership, and for which a carefully selected control plant exists. Results suggest that FDIs can have positive scale and technique effects on the environmental performance of acquired plants. These effects are especially pronounced for small firms and firms that were relatively inefficient prior to acquisition. The third essay analyzes the impact of oil price shocks on the US economy at the individual state level. The study accounts for the endogeneity of changes in crude oil price, differences among states, and spillover effects with neighboring states. Results suggest that the implications of higher oil prices for a

  2. Essays on consequences of economic integration

    NASA Astrophysics Data System (ADS)

    Chintrakarn, Pandej

    2007-12-01

    Economic integration is a term used to describe how different aspects between economies are integrated. As economic integration increases, the barriers of trade between markets diminishes. The most integrated economy today, between independent nations, is the European Union and its euro zone. This dissertation consists of three essays which examine consequences of economic integration. The debate over the environmental consequences of free trade is not only quite heated, but also entails significant policy ramifications. Recently, cross-sectional analysis at the country level has made use of exogenous determinants of trade to identify the causal effect of trade on the environment, finding moderate evidence of a beneficial impact of expanded trade on environmental quality. Given the stakes involved, the first essay revisits this finding using subnational data on 'trade' flows across US states and several measures of pollution. Not only does the analysis shed further light on the debate at the international level, but also addresses a heretofore unexamined question: Does greater inter-regional commerce at the subnational level harm the environment? The findings are striking, providing further evidence against a negative environmental impact of trade for the majority of measures analyzed. However, several sources of heterogeneity arise that are noteworthy. The second essay investigates the effect of the euro on trade among EMU members. Using various semi-nonparametric methods based on matching, the results suggest that the euro has a statistical and economic impact on trade. The results show that two countries sharing the euro currency trade somewhere between 9% and 14% more than other country-pairs. In addition, there is no evidence of trade diversion due to the euro. In one strand of research, analysts examine trends in and the determinants of energy usage and intensity. In a second strand, researchers analyze the impact of trade flows on environmental outcomes

  3. Lessons from New Zealand's introduction of pictorial health warnings on tobacco packaging.

    PubMed

    Hoek, Janet; Wilson, Nick; Allen, Matthew; Edwards, Richard; Thomson, George; Li, Judy

    2010-11-01

    While international evidence suggests that featuring pictorial health warnings on tobacco packaging is an effective tobacco control intervention, the process used to introduce these new warnings has not been well documented. We examined relevant documents and interviewed officials responsible for this process in New Zealand. We found that, despite tobacco companies' opposition to pictorial health warnings and the resource constraints facing health authorities, the implementation process was generally robust and successful. Potential lessons for other countries planning to introduce or refresh existing pictorial health warnings include: (i) strengthening the link between image research and policy; (ii) requiring frequent image development and refreshment; (iii) using larger pictures (e.g. 80% of the front of the packet); (iv) developing themes that recognize concerns held by different smoker sub-groups; and (v) running integrated mass media campaigns when the warnings are introduced. All countries could also support moves by the World Health Organization Framework Convention on Tobacco Control's Secretariat to develop an international bank of copyright-free warnings.

  4. Recent research results in stereo 3-D pictorial displays at Langley Research Center

    NASA Technical Reports Server (NTRS)

    Parrish, Russell V.; Busquets, Anthony M.; Williams, Steven P.

    1990-01-01

    Recent results from a NASA-Langley program which addressed stereo 3D pictorial displays from a comprehensive standpoint are reviewed. The program dealt with human factors issues and display technology aspects, as well as flight display applications. The human factors findings include addressing a fundamental issue challenging the application of stereoscopic displays in head-down flight applications, with the determination that stereoacuity is unaffected by the short-term use of stereo 3D displays. While stereoacuity has been a traditional measurement of depth perception abilities, it is a measure of relative depth, rather than actual depth (absolute depth). Therefore, depth perception effects based on size and distance judgments and long-term stereo exposure remain issues to be investigated. The applications of stereo 3D to pictorial flight displays within the program have repeatedly demonstrated increases in pilot situational awareness and task performance improvements. Moreover, these improvements have been obtained within the constraints of the limited viewing volume available with conventional stereo displays. A number of stereo 3D pictorial display applications are described, including recovery from flight-path offset, helicopter hover, and emulated helmet-mounted display.

  5. Impact of Medicare Shared Savings Program Accountable Care Organizations at Screening Mammography: A Retrospective Cohort Study.

    PubMed

    Narayan, Anand K; Harvey, Susan C; Durand, Daniel J

    2017-02-01

    Purpose To evaluate the impact of accountable care organizations (ACOs) on use of screening mammography in the Medicare Shared Savings Program (MSSP), the largest value-based reimbursement program in U.S.

  6. PATIENT EXPOSURE DURING PLAIN RADIOGRAPHY AND MAMMOGRAPHY IN JAPAN IN 1974-2014.

    PubMed

    Matsunaga, Yuta; Kawaguchi, Ai; Kobayashi, Kenichi; Kobayashi, Masanao; Asada, Yasuki; Minami, Kazuyuki; Suzuki, Shoichi; Chida, Koichi

    2017-03-01

    We investigated changes in the entrance skin dose (ESD) and the mean glandular dose (MGD) during plain radiography or mammography in Japan from 1974 to 2014. Surveys regarding the conditions used for plain radiography and mammography were performed throughout Japan in 1974, 1979, 1989, 1993, 1997, 2001, 2003, 2007, 2011 and 2014. The anatomical regions considered were categorised as follows: skull anteroposterior (AP), lumbar AP, lumbar lateral (LAT), pelvis (AP), ankle, chest posteroanterior (PA), Guthmann (lateral pelviography for pregnant women), infant hip joint and mammography. The doses for all anatomical regions decreased from 1974 to 1993. The MGD for mammography remained low from 1993 to 2014, and the ESDs for chest (PA) radiography trended upward. After the 2000s, the use of digital imaging increased in Japan. This is the first long-term study to examine changes in ESDs and MGDs in Japan.

  7. Ultrasound as an Adjunct to Mammography for Breast Cancer Screening: A Health Technology Assessment

    PubMed Central

    Nikitovic-Jokic, Milica; Tu, Hong Anh; Palimaka, Stefan; Higgins, Caroline; Holubowich, Corinne

    2016-01-01

    Background Screening with mammography can detect breast cancer early, before clinical symptoms appear. Some cancers, however, are not captured with mammography screening alone. Ultrasound has been suggested as a safe adjunct screening tool that can detect breast cancers missed on mammography. We investigated the benefits, harms, cost-effectiveness, and cost burden of ultrasound as an adjunct to mammography compared with mammography alone for screening women at average risk and at high risk for breast cancer. Methods We searched Ovid MEDLINE, Ovid Embase, EBM Reviews, and the NHS Economic Evaluation Database, from January 1998 to June 2015, for evidence of effectiveness, harms, diagnostic accuracy, and cost-effectiveness. Only studies evaluating the use of ultrasound as an adjunct to mammography in the specified populations were included. We also conducted a cost analysis to estimate the costs in Ontario over the next 5 years to fund ultrasound as an adjunct to mammography in breast cancer screening for high-risk women who are contraindicated for MRI, the current standard of care to supplement mammography. Results No studies in average-risk women met the inclusion criteria of the clinical review. We included 5 prospective, paired cohort studies in high-risk women, 4 of which were relevant to the Ontario context. Adjunct ultrasound identified between 2.3 and 5.9 additional breast cancers per 1,000 screens. The average pooled sensitivity of mammography and ultrasound was 53%, a statistically significant increase relative to mammography alone (absolute increase 13%; P < .05). The average pooled specificity of the combined test was 96%, an absolute increase in the false-positive rate of 2% relative to mammography screening alone. The GRADE for this body of evidence was low. Additional annual costs of using breast ultrasound as an adjunct to mammography for high-risk women in Ontario contraindicated for MRI would range from $15,500 to $30,250 in the next 5 years

  8. Accommodating Marked Features of Ebonics in Freshman Essays: From a Narrative Essay to a Research Paper.

    ERIC Educational Resources Information Center

    Wang, Xiao

    For an educator who teaches English in a multicultural setting, the best way to accommodate marked features of African-American vernacular English (AAVE) in black students' freshman essays is to preserve these features in teaching students narrative writings and guide African-American students to avoid these features in expository (academic)…

  9. Digital Mammography: Development of an Advanced Computer-Aided Diagnosis System for Breast Cancer Detection

    DTIC Science & Technology

    2006-05-01

    aided diagnosis of masses with full-field digital mammography,” Acad. Radiol. 9, 4–12 2002. 34D. Gur, J. S. Stalder, L. A. Hardesty , B. Zheng, J. H...Pickett RM , D’Orsi CJ. Stereo- scopic digital mammography: improving detection and diagnosis of breast cancer. Berlin, Germany: International Congress...other is the root-mean-square ( RMS ) distance between the computer and manually identified pectoral boundary. For 118 MLO view mammograms, 99.2% (117

  10. Dosimetry and kVp standardization for quality assurance of mammography

    NASA Astrophysics Data System (ADS)

    Chu, Chien-Hau; Yuan, Ming-Chen; Huang, Wen-Sheng; Hsieh, Bor-Tsung

    2014-11-01

    Breast cancer mortality rates were significantly reduced in Taiwan after achieving early-stage monitoring with mammography screening. This study establishes an appropriate and traceable calibration infrastructure, which offers calibration services for mammography X-ray quality assurance instrumentation, which is performed clinically on a regular basis. The entrance air kerma, HVL, and kVp of mammography equipment with five different target/filter combinations can be taken as adequate indicators for the level of average glandular dose (AGD). The primary dose standard in mammography uses a free-air ionization chamber to estimate the rate of air kerma. Several correction factors were determined by Monte Carlo simulations and experiments. A secondary kVp standard in mammography is in accordance with the IEC 61676 recommendations. The calibration system of kVp meter uses a high-voltage divider, which is traceable to ITRI primary standard in Taiwan. Dose and kVp verifications were conducted by mammography instruments, which were previously calibrated by NIST and PTB. The evaluation results indicate that the capabilities of this irradiation system met the ISO 4037-1 requirements. The expanded uncertainties (k=2) were 1.03% and 1.6% when the mammography X-ray air kerma rate and kVp meter calibration factors were evaluated using ISO GUM. Experimental verification and a comparison with NIST using transfer ionization chambers yielded differences in calibration factors. Comparison with the PTB using kVp meter indicated a less than 1% difference. The results showed that dose and kVp standards were in reasonable agreement with standard uncertainty. The low uncertainties associated with the obtained results in this work show that the standardization employed can be accurately used for calibration of instrument in mammography in Taiwan.

  11. At what age should screening mammography be recommended for Asian women?

    PubMed

    Tsuchida, Junko; Nagahashi, Masayuki; Rashid, Omar M; Takabe, Kazuaki; Wakai, Toshifumi

    2015-07-01

    Although regular screening mammography has been suggested to be associated with improvements in the relative survival of breast cancer in recent years, the appropriate age to start screening mammography remains controversial. In November 2009, the United States Preventive Service Task Force published updated guidelines for breast cancer, which no longer support routine screening mammography for women aged 40-49 years, but instead, defer the choice of screening in that age group to the patient and physician. The age to begin screening differs between guidelines, including those from the Task Force, the American Cancer Society and the World Health Organization. It remains unclear how this discrepancy impacts patient survival, especially among certain subpopulations. Although the biological characteristics of breast cancer and peak age of incidence differ among different ethnic populations, there have been few reports that evaluate the starting age for screening mammography based on ethnicity. Here, we discuss the benefits and harm of screening mammography in the fifth decade, and re-evaluate the starting age for screening mammography taking ethnicity into account, focusing on the Asian population. Breast cancer incidence peaked in the fifth decade in Asian women, which has been thought to be due to a combination of biological and environmental factors. Previous reports suggest that Asian women in their 40s may receive more benefit and less harm from screening mammography than the age-matched non-Asian US population. Therefore, starting screening mammography at age 40 may be beneficial for women of Asian ethnicity in well-resourced countries, such as Japanese women who reside in Japan.

  12. Comparative Study Of Image Enhancement Algorithms For Digital And Film Mammography

    SciTech Connect

    Delgado-Gonzalez, A.

    2008-08-11

    Here we discuss the application of edge enhancement algorithms on images obtained with a Mammography System which has a Selenium Detector and on the other hand, on images obtained from digitized film mammography. Comparative analysis of such images includes the study of technical aspects of image acquisition, storage, compression and display. A protocol for a local database has been created as a result of this study.

  13. Adaptive Computer-Assisted Mammography Training for Improved Breast Cancer Screening

    DTIC Science & Technology

    2013-10-01

    disease . The project includes: Observer studies to collect reading data from radiology trainees; Extraction of image features (human- and computer- based...mammography in breast cancer detection and lower mortality associated the disease . 15. SUBJECT TERMS Mammography, radiology, education, user modeling...associated the disease . BODY: Overall progress: Specific aim Expected Actual 1.1 Prepare the database of screening mammograms (year 1, months 1-6

  14. High-Resolution Mammography Detector Employing Optical Switching Readout

    NASA Astrophysics Data System (ADS)

    Irisawa, Kaku; Kaneko, Yasuhisa; Yamane, Katsutoshi; Sendai, Tomonari; Hosoi, Yuichi

    Conceiving a new detector structure, FUJIFILM Corporation has successfully put its invention of an X-ray detector employing "Optical Switching" into practical use. Since Optical Switching Technology allows an electrode structure to be easily designed, both high resolution of pixel pitch and low electrical noise readout have been achieved, which have consequently realized the world's smallest pixel size of 50×50 μm2 from a Direct-conversion FPD system as well as high DQE. The digital mammography system equipped with this detector enables to acquire high definition images while maintaining granularity. Its outstanding feature is to be able to acquire high-precision images of microcalcifications which is an important index in breast examination.

  15. [Advances in research on automatic exposure control of mammography system].

    PubMed

    Wang, Guoyi; Ye, Chengfu; Wu, Haiming; Wang, Tainfu; Zhang, Hong

    2014-12-01

    Mammography imaging is one of the most demanding imaging modalities from the point of view of the bal- ance between image quality (the visibility of small size and/or low contrast structures) and dose (screening of many asymptomatic people). Therefore, since the introduction of the first dedicated mammographic units, many efforts have been directed to seek the best possible image quality while minimizing patient dose. The performance of auto- matic exposure control (AEC) is the manifestation of this demand. The theory of AEC includes exposure detection and optimization and also involves some accomplished methodology. This review presents the development and present situa- tion of spectrum optimization, detector evolution, and the way how to accomplish and evaluate AEC methods.

  16. Do shorter wavelengths improve contrast in optical mammography?

    NASA Astrophysics Data System (ADS)

    Taroni, P.; Pifferi, A.; Torricelli, A.; Spinelli, L.; Danesini, G. M.; Cubeddu, R.

    2004-04-01

    The detection of tumours with time-resolved transmittance imaging relies essentially on blood absorption. Previous theoretical and phantom studies have shown that both contrast and spatial resolution of optical images are affected by the optical properties of the background medium, and high absorption and scattering are generally beneficial. Based on these observations, wavelengths shorter than presently used (680-780 nm) could be profitable for optical mammography. A study was thus performed analysing time-resolved transmittance images at 637, 656, 683 and 785 nm obtained from 26 patients bearing 16 tumours and 15 cysts. The optical contrast proved to increase upon decreasing wavelengths for the detection of cancers in late-gated intensity images, with higher gain in contrast for lesions of smaller size (<1.5 cm diameter). For cysts either a progressive increase or decrease in contrast with wavelength was observed in scattering images.

  17. Photoacoustic mammography capable of simultaneously acquiring photoacoustic and ultrasound images

    NASA Astrophysics Data System (ADS)

    Asao, Yasufumi; Hashizume, Yohei; Suita, Takahiro; Nagae, Ken-ichi; Fukutani, Kazuhiko; Sudo, Yoshiaki; Matsushita, Toshikazu; Kobayashi, Shuichi; Tokiwa, Mariko; Yamaga, Iku; Fakhrejahani, Elham; Torii, Masae; Kawashima, Masahiro; Takada, Masahiro; Kanao, Shotaro; Kataoka, Masako; Shiina, Tsuyoshi; Toi, Masakazu

    2016-11-01

    We have constructed a prototype photoacoustic mammography system (PAM-02) capable of simultaneously acquiring photoacoustic (PA) and ultrasound (US) images. Each PA, US, and fused PA/US image can be acquired over a wide area of the breast using the scanning module of a US transducer, a PA detector, and optical prisms. The resolution of the PA images exhibits improvement from 2 to 1 mm compared to images acquired using our previous prototype. The maximum scan area of PAM-02 is 90 mm along the horizontal axis and 150 mm along the vertical axis. In a phantom experiment, the available depth was at least 45 mm. A representative example of the application of the PAM-02 prototype in clinical research at Kyoto University is presented and shows S-factor images, which are considered an approximation parameter related to hemoglobin saturation of tumor-related blood vessels. We confirmed the applicability of the system for anatomical and biological research.

  18. Physical characteristics of a full-field digital mammography system

    NASA Astrophysics Data System (ADS)

    Suryanarayanan, Sankararaman; Karellas, Andrew; Vedantham, Srinivasan

    2004-11-01

    The physical performance characteristics of a flat-panel clinical full-field digital mammography (FFDM) system were investigated for a variety of mammographic X-ray spectral conditions. The system was investigated using 26 kVp: Mo/Mo, 28 kVp: Mo/Rh, and 30 kVp: Rh/Rh, with polymethyl methacrylate (PMMA) "tissue equivalent material" of thickness 20, 45, and 60 mm for each of three X-ray spectra, resulting in nine different spectral conditions. The experimental results were compared with a theoretical cascaded linear systems-based model that has been developed independently by other investigators. The FFDM imager (Senographe 2000D, GE Medical Systems, Milwaukee, WI) uses an amorphous silicon (aSi:H) photodiode (100 μm pixel) array directly coupled to a cesium iodide (CsI) scintillator. The spatial resolution of the digital mammography system was determined by measuring the presampling modulation transfer function (MTF). The noise power spectra (NPS) of the system were measured under the different mammographic X-ray spectral conditions at an exposure of approximately 10 mR to the detector from which corresponding detective quantum efficiencies (DQE) were determined. The experimental results provide additional information on the performance of the mammographic system for a broader range of experimental conditions than have been reported in the past. The flat-panel imager exhibits favorable physical quality characteristics under the conditions investigated. The experimental results were compared with theoretical estimates under various spectral conditions and demonstrated good agreement.

  19. Visibility of microcalcifications in computed and screen-film mammography

    NASA Astrophysics Data System (ADS)

    Cowen, Arnold R.; Launders, Jason H.; Jadav, Mark; Brettle, David S.

    1997-08-01

    Due to the clinically and technically demanding nature of breast x-ray imaging, mammography still remains one of the few essentially film-based radiological imaging techniques in modern medical imaging. There are a range of possible benefits available if a practical and economical direct digital imaging technique can be introduced to routine clinical practice. There has been much debate regarding the minimum specification required for direct digital acquisition. One such direct digital system available is computed radiography (CR), which has a modest specification when compared with modern screen-film mammography (SFM) systems. This paper details two psychophysical studies in which the detection of simulated microcalcifications with CR has been directly compared to that with SFM. The first study found that under scatter-free conditions the minimum detectable size of microcalcification was approximately for both SFM and CR. The second study found that SFM had a 4.6% higher probability of observers being able to correctly identify the shape of diameter test details; there was no significant difference for either larger or smaller test details. From the results of these studies it has been demonstrated that the modest specification of CR, in terms of limiting resolution, does not translate into a dramatic difference in the perception of details at the limit of detectability. When judging the imaging performance of a system it is more important to compare the signal-to-noise ratio transfer spectrum characteristics, rather than simply the modulation transfer function.

  20. Evaluation of automatic exposure control options in digital mammography.

    PubMed

    Zhou, Yifang; Scott, Alexander; Allahverdian, Janet; Frankel, Steve

    2014-01-01

    To quantify the trade-offs of dose and image quality among pre-loaded automatic exposure control (AEC) options in digital mammography, two AEC tables from the Hologic Selenia digital mammography system were compared: the default AEC "table 0" and AEC "table 1". Realistically-shaped phantoms consisting of tissue-equivalent material of various thicknesses (4.5 cm-7 cm) were imaged to obtain a figure of merit (FOM), the squared contrast-to-noise ratio per mean glandular dose. To relate the results to pathological findings and to evaluate the overall performance, the measured contrast-to-noise ratios were applied to simulated lesions on the anthropomorphic breast phantom images, producing various lesion configurations which were blindly scored. It was found that the AEC table 1 improves the low contrast FOM by 11% to 20% for the breast thicknesses of 4.5-6 cm. However, for the 7 cm thick breast, the AEC table 1 decreases the low contrast FOM by 17%. For microcalcifications, the AEC table 1 improves the FOM slightly for the breast thicknesses of 4.5--6 cm and decreases it by 18% at a thickness of 7 cm. The lesion simulation showed enhanced contrast due to the AEC table 1 for the breast thicknesses of 5 cm, 6 cm, and 7 cm, but the enhancement gradually reduces as the thickness increases. The lesion reading showed that the microcalcification detection was scored significantly higher from the AEC table 1 for the thicknesses 5 cm, 6 cm, and 7 cm. The corresponding improvement of mass detection scores was also observed but not consistently significant over the thickness range.

  1. Scatter correction in digital mammography based on image deconvolution.

    PubMed

    Ducote, J L; Molloi, S

    2010-03-07

    X-ray scatter is a major cause of nonlinearity in densitometry measurements using digital mammography. Previous scatter correction techniques have primarily used a single scatter point spread function to estimate x-ray scatter. In this study, a new algorithm to correct x-ray scatter based on image convolution was implemented using a spatially variant scatter point spread function which is energy and thickness dependent. The scatter kernel was characterized in terms of its scattering fraction (SF) and scatter radial extent (k) on uniform Lucite phantoms with thickness of 0.8-8.0 cm. The algorithm operates on a pixel-by-pixel basis by grouping pixels of similar thicknesses into a series of mask images that are individually deconvolved using Fourier image analysis with a distinct kernel for each image. The algorithm was evaluated with three Lucite step phantoms and one anthropomorphic breast phantom using a full-field digital mammography system at energies of 24, 28, 31 and 49 kVp. The true primary signal was measured with a multi-hole collimator. The effect on image quality was also evaluated. For all 16 studies, the average mean percentage error in estimating the true primary signal was found to be -2.13% and the average rms percentage error was 2.60%. The image quality was seen to improve at every energy up to 25% at 49 kVp. The results indicate that a technique based on a spatially variant scatter point spread function can accurately estimate x-ray scatter.

  2. MO-AB-207-04: ACR Update in Mammography

    SciTech Connect

    Berns, E.

    2015-06-15

    A goal of an imaging accreditation program is to ensure adequate image quality, verify appropriate staff qualifications, and to assure patient and personnel safety. Currently, more than 35,000 facilities in 10 modalities have been accredited by the American College of Radiology (ACR), making the ACR program one of the most prolific accreditation options in the U.S. In addition, ACR is one of the accepted accreditations required by some state laws, CMS/MIPPA insurance and others. Familiarity with the ACR accreditation process is therefore essential to clinical diagnostic medical physicists. Maintaining sufficient knowledge of the ACR program must include keeping up-to-date as the various modality requirements are refined to better serve the goals of the program and to accommodate newer technologies and practices. This session consists of presentations from authorities in four ACR accreditation modality programs, including magnetic resonance imaging, computed tomography, nuclear medicine, and mammography. Each speaker will discuss the general components of the modality program and address any recent changes to the requirements. Learning Objectives: To understand the requirements of the ACR MR Accreditation program. The discussion will include accreditation of whole-body general purpose magnets, dedicated extremity systems well as breast MRI accreditation. Anticipated updates to the ACR MRI Quality Control Manual will also be reviewed. To understand the requirements of the ACR CT accreditation program, including updates to the QC manual as well as updates through the FAQ process. To understand the requirements of the ACR nuclear medicine accreditation program, and the role of the physicist in annual equipment surveys and the set up and supervision of the routine QC program. To understand the current ACR MAP Accreditation requirement and present the concepts and structure of the forthcoming ACR Digital Mammography QC Manual and Program.

  3. Four Principles to Consider Before Advising Women on Screening Mammography.

    PubMed

    Keen, John D; Jørgensen, Karsten J

    2015-11-01

    This article reviews four important screening principles applicable to screening mammography in order to facilitate informed choice. The first principle is that screening may help, hurt, or have no effect. In order to reduce mortality and mastectomy rates, screening must reduce the rate of advanced disease, which likely has not happened. Through overdiagnosis, screening produces substantial harm by increasing both lumpectomy and mastectomy rates, which offsets the often-promised benefit of less invasive therapy. Next, all-cause mortality is the most reliable way to measure the efficacy of a screening intervention. Disease-specific mortality is biased due to difficulties in attribution of cause of death and to increased mortality due to overdiagnosis and the resulting overtreatment with radiotherapy and chemotherapy. To enhance participation, the benefit from screening is often presented in relative instead of absolute terms. Third, some screening statistics must be interpreted with caution. Increased survival time and the percentage of early-stage tumors at detection sound plausible, but are affected by lead-time and length biases. In addition, analyses that only include women who attend screening cannot reliably correct for selection bias. The final principle is that accounting for tumor biology is important for accurate estimates of lead time, and the potential benefit from screening. Since "early detection" is actually late in a tumor's lifetime, the time window when screen detection might extend a woman's life is narrow, as many tumors that can form metastases will already have done so. Instead of encouraging screening mammography, physicians should help women make an informed decision as with any medical intervention.

  4. A comprehensive model for quantum noise characterization in digital mammography.

    PubMed

    Monnin, P; Bosmans, H; Verdun, F R; Marshall, N W

    2016-03-07

    A version of cascaded systems analysis was developed specifically with the aim of studying quantum noise propagation in x-ray detectors. Signal and quantum noise propagation was then modelled in four types of x-ray detectors used for digital mammography: four flat panel systems, one computed radiography and one slot-scan silicon wafer based photon counting device. As required inputs to the model, the two dimensional (2D) modulation transfer function (MTF), noise power spectra (NPS) and detective quantum efficiency (DQE) were measured for six mammography systems that utilized these different detectors. A new method to reconstruct anisotropic 2D presampling MTF matrices from 1D radial MTFs measured along different angular directions across the detector is described; an image of a sharp, circular disc was used for this purpose. The effective pixel fill factor for the FP systems was determined from the axial 1D presampling MTFs measured with a square sharp edge along the two orthogonal directions of the pixel lattice. Expectation MTFs were then calculated by averaging the radial MTFs over all possible phases and the 2D EMTF formed with the same reconstruction technique used for the 2D presampling MTF. The quantum NPS was then established by noise decomposition from homogenous images acquired as a function of detector air kerma. This was further decomposed into the correlated and uncorrelated quantum components by fitting the radially averaged quantum NPS with the radially averaged EMTF(2). This whole procedure allowed a detailed analysis of the influence of aliasing, signal and noise decorrelation, x-ray capture efficiency and global secondary gain on NPS and detector DQE. The influence of noise statistics, pixel fill factor and additional electronic and fixed pattern noises on the DQE was also studied. The 2D cascaded model and decompositions performed on the acquired images also enlightened the observed quantum NPS and DQE anisotropy.

  5. Geographic Disparities in Mammography Capacity in the South: A Longitudinal Assessment of Supply and Demand

    PubMed Central

    Eberth, Jan M; Eschbach, Karl; Morris, Jeffrey S; Nguyen, Hoang T; Hossain, Md Monir; Elting, Linda S

    2014-01-01

    ObjectiveStudies have shown that there is sufficient availability of mammography; however, little is known about geographic variation in capacity. The purpose of this study was to determine the locations and extent of over/undersupply of mammography in 14 southern states from 2002 to 2008. Data SourcesMammography facility data were collected from the U.S. Food and Drug Administration (FDA). Population estimates, used to estimate the potential demand for mammography, were obtained from GeoLytics Inc. Study DesignUsing the two-step floating catchment area method, we calculated spatial accessibility at the block group level and categorized the resulting index to represent the extent of under/oversupply relative to the potential demand. Principal FindingsResults show decreasing availability of mammography over time. The extent of over/undersupply varied significantly across the South. Reductions in capacity occurred primarily in areas with an oversupply of machines, resulting in a 68 percent decrease in the percent of women living in excess capacity areas from 2002 to 2008. The percent of women living in poor capacity areas rose by 10 percent from 2002 to 2008. ConclusionsOur study found decreasing mammography availability and capacity over time, with substantial variation across states. This information can assist providers and policy makers in their business planning and resource allocation decisions. PMID:23829179

  6. Correlation between molybdenum target mammography signs and pathological prognostic factors of breast cancer.

    PubMed

    Zhang, Y; Ma, A D; Jia, H X

    2016-01-01

    This study explores the correlation between molybdenum target (mo-target) mammography signs and pathological prognostic factors of breast cancer. We selected 320 breast cancer patients who were treated between January 2014 and January 2016; using single-factor and multiple-factor logistic regression method, we made correlation analysis on their clinical features, pathological features and mo-target mammography signs. Among mo-target mammography signs, lumps accompanied with calcification and blurry edge were associated with high histologic grades; lumps accompanied with calcification and clear edge were associated with Ki-67 positive; compared with the patients who had lumps with non-stellate edges, positive rates of estrogen receptor (ER) and progesterone receptor (PR) were significantly higher for the patients who had lumps with stellate edges (p < 0.01), while positive rate of human epidermal growth factor receptor-2 (HER-2) and tumor proliferative activity were significantly lower (p < 0.05, p < 0.01). According to the study, we can conclude that mo-target mammography signs mainly include lumps and calcification. Mo-target mammography can improve the accuracy of diagnosis and reduce misdiagnosis or missed diagnosis. Part of mo-target mammography signs are associated with clinical pathology prognostic factors; by grasping the relation, breast cancer patient conditions are expected to be relieved.

  7. Keeping mammography referral appointments: motivation, health beliefs, and access barriers experienced by older minority women.

    PubMed

    Bernstein, J; Mutschler, P; Bernstein, E

    2000-01-01

    Older women of color tend to have much lower rates of regular mammography screening for breast cancer than younger Caucasian women; yet, they have higher rates of mortality. This study was designed to increase mammography rates among inner-city women aged 50 years or older. Another goal was to investigate differences in mammography utilization related to race/ethnicity and language after barriers associated with cost and the difficulty of making an appointment are removed. A peer delivered intervention, which consisted of interview, mammography referral, and the scheduling of a next-day appointment, was conducted among a convenience sample of 151 culturally and racially diverse older women through a primary care referral project operating within an urban emergency department (ED). A brief motivational interview and mammography referral at the time of an ED visit, including scheduling of a next-day no cost appointment, was followed by a cross-sectional telephone survey of utilization and motivating and hindering factors. Follow-up was achieved with 96 women (66%). Fifty-eight women (60%) had a post-intervention mammogram; of those, 69% were first time users. More than 90% planned a repeat mammogram the following year. Of the 27 who did not receive a mammogram, 21 (77%) requested a "second try" appointment. These findings demonstrate that an interactive intervention among older women of color has the potential to dramatically increase mammography rates.

  8. Comparison of the Mammography, Contrast-Enhanced Spectral Mammography and Ultrasonography in a Group of 116 patients.

    PubMed

    Luczyńska, Elzbieta; Heinze, Sylwia; Adamczyk, Agnieszka; Rys, Janusz; Mitus, Jerzy W; Hendrick, Edward

    2016-08-01

    Mammography (MG) is the gold-standard in breast cancer detection - the only method documented to reduce breast cancer mortality. Breast ultrasound (US) has been shown to increase sensitivity to breast cancers in screening women with dense breasts. Contrast-enhanced spectral mammography (CESM) is a novel technique intensively developed in the last few years. The goal of this study was to compare the sensitivity, specificity and accuracy of MG, US and CESM in detecting malignant breast lesions. The study included 116 patients. All patients were symptomatic and underwent MG, US and CESM. A radiologist with 20 years of experience in US and MG breast imaging and 1 year of experience in CESM reviewed images acquired in each of the three modalities separately, within an interval of 14-30 days. All identified lesions were confirmed at core biopsy. BI-RADS classifications on US, MG and CESM were compared to histopathology. MG, CESM and US were compared among 116 patients with 137 lesions encountered. Sensitivity of CESM was 100%, significantly higher than that of MG (90%, p<0.004) or US (92%, p<0.01). CESM accuracy was 78%, also higher than MG (69%, p<0.004) and US (70%, p=0.03). There was no statistically significant difference between AUCs for CESM and US (both 0.83). The AUCs of both US and CESM, however, were significantly larger than that of MG (p<0.0004 for each). CESM permitted better detection of malignant lesions than both MG and US, read individually. CESM found lesion enhancement in some benign lesions, as well, yielding a rate of false-positive diagnoses similar to that of MG and US.

  9. Essays on regulation, institutions, and industrial organization

    NASA Astrophysics Data System (ADS)

    Bergara, Mario Esteban

    Essay I develops a comparative institutional analysis of network access price regulation and "light-handed" regulation. While the former is a specific-agency-based arrangement with higher political influence, the latter is a court-based system. Consequently, the main trade-off between both frameworks reflects the merits of having efficient political and judicial institutions. Price regulation is superior when distributional concerns are irrelevant and information asymmetries are lower. Poorly functioning political systems and high welfare costs of raising funds make price regulation less attractive. Light regulation is more attractive when potential rents are smaller, the monopolist is more risk averse, the judicial system is more efficient, and the threat of government intervention is more credible. The possibility of private transfers makes price regulation more advantageous. Higher information asymmetries among firms makes light-handed regulation more attractive. The main results are consistent with a plausible interpretation of the drastic deregulatory process in New Zealand. Essay II studies the preliminary effects of the deregulation of direct access in the New Zealand's electricity market. A slight improvement in quality standards and an overall efficiency increase took place after two years of deregulation. Retailers were able to successfully enter in large demand, dense areas, with a large proportion of industrial and commercial users, where incumbents were not distributing electricity efficiently. Pricing policies appears to be influenced by market forces (associated to economic and demographic characteristics) as expected in a light regulatory framework. Essay III focuses on the possibility of endogenous sunk costs and the introduction of new products. Firms that exert some monopoly power in one market and introduce a new good whose demand is determined by a broader set of consumers might be forced to change their competing strategies. If the new product

  10. Essays concerning the cellulosic biofuel industry

    NASA Astrophysics Data System (ADS)

    Rosburg, Alicia Sue

    Despite market-based incentives and mandated production, the U.S. cellulosic biofuel industry has been slow to develop. This dissertation explores the economic factors that have limited industry development along with important economic tradeoffs that will be encountered with commercial-scale production. The first essay provides an overview of the policies, potential, and challenges of the biofuel industry, with a focus on cellulosic biofuel. The second essay considers the economics of cellulosic biofuel production. Breakeven models of the local feedstock supply system and biofuel refining process are constructed to develop the Biofuel Breakeven (BioBreak) program, a stochastic, Excel-based program that evaluates the feasibility of local biofuel and biomass markets under various policy and market scenarios. An application of the BioBreak program is presented using expected market conditions for 14 local cellulosic biofuel markets that vary by feedstock and location. The economic costs of biofuel production identified from the BioBreak application are higher than frequently anticipated and raise questions about the potential of cellulosic ethanol as a sustainable and economical substitute for conventional fuels. Program results also are extended using life-cycle analysis to evaluate the cost of reducing GHG emissions by substituting cellulosic ethanol for conventional fuel. The third essay takes a closer look at the economic trade-offs within the biorefinery industry and feedstock production processes. A long-run biomass production through bioenergy conversion cost model is developed that incorporates heterogeneity of biomass suppliers within and between local markets. The model builds on previous literature by treating biomass as a non-commoditized feedstock and relaxes the common assumption of fixed biomass density and price within local markets. An empirical application is provided for switchgrass-based ethanol production within U.S. crop reporting districts

  11. Essays in energy economics: The electricity industry

    NASA Astrophysics Data System (ADS)

    Martinez-Chombo, Eduardo

    Electricity demand analysis using cointegration and error-correction models with time varying parameters: The Mexican case. In this essay we show how some flexibility can be allowed in modeling the parameters of the electricity demand function by employing the time varying coefficient (TVC) cointegrating model developed by Park and Hahn (1999). With the income elasticity of electricity demand modeled as a TVC, we perform tests to examine the adequacy of the proposed model against the cointegrating regression with fixed coefficients, as well as against the spuriousness of the regression with TVC. The results reject the specification of the model with fixed coefficients and favor the proposed model. We also show how some flexibility is gained in the specification of the error correction model based on the proposed TVC cointegrating model, by including more lags of the error correction term as predetermined variables. Finally, we present the results of some out-of-sample forecast comparison among competing models. Electricity demand and supply in Mexico. In this essay we present a simplified model of the Mexican electricity transmission network. We use the model to approximate the marginal cost of supplying electricity to consumers in different locations and at different times of the year. We examine how costs and system operations will be affected by proposed investments in generation and transmission capacity given a forecast of growth in regional electricity demands. Decomposing electricity prices with jumps. In this essay we propose a model that decomposes electricity prices into two independent stochastic processes: one that represents the "normal" pattern of electricity prices and the other that captures temporary shocks, or "jumps", with non-lasting effects in the market. Each contains specific mean reverting parameters to estimate. In order to identify such components we specify a state-space model with regime switching. Using Kim's (1994) filtering algorithm

  12. Relationship Between Perceived Risk and Physician Recommendation and Repeat Mammography in the Female Population in Tehran, Iran.

    PubMed

    Moshki, Mahdi; Taymoori, Parvaneh; Khodamoradi, Sahmireh; Roshani, Daem

    2016-01-01

    Iranian women are at high risk of low compliance with repeat mammography due to a lack of awareness about breast cancer, negative previous experiences, cultural beliefs, and no regular visits to a physician. Thus research is needed to explore factors associated with repeated mammography participation. Applying the concept of perceived risk as the guiding model, this study aimed to test the fit and strength of the relationship between perceived risk and physician recommendation in explaining repeat mammography. A total of 601 women, aged 50 years and older referred to mammography centers in region 6, were recruited via a convenience sampling method. Using path analysis, family history of breast cancer and other types of cancer were modeled as antecedent perceived risk, and physician recommendation and knowledge were modeled as an antecedent of the number of mammography visits. The model explained 49% of the variance in repeat mammography. The two factors of physician recommendation and breast self-examination had significant direct effects (P < 0.05) on repeat mammography. Perceived risk, knowledge, and family history of breast cancer had significant indirect effects on repeat mammography through physician recommendation. The results of this study provide a background for further research and interventions not only on Iranian women but also on similar cultural groups and immigrants who have been neglected to date in the mammography literature.

  13. Evaluation of the Relationship Between Family History of Breast Cancer and Risk Perception and Impacts on Repetition of Mammography.

    PubMed

    Khoshravesh, Sahar; Taymoori, Parvaneh; Roshani, Daem

    2016-01-01

    Since the mean age of breast cancer in women living in developing countries, compared with those in developed countries, is lower by about 10 years, repetition of mammography can play an important role in reducing morbidity and mortality. Hence, this study aimed to investigate the relationship between family history of breast cancer and risk perception and its impact on repetition of mammography. In this cross-sectional study, 1,507 women aged 50 years and older, referred to the mammography center of Regions 1 and 6 in Tehran, Iran, were enrolled. Data were collected using a self-report questionnaire and analyzed using SPSS and LISREL. According to our findings, knowledge about the time interval of mammography was found to have the highest correlation with repetition of mammography (r =0.4). Among the demographic variables, marital status (β= -0.1) and family history of breast cancer (β=0.1) had the most direct and significant impact on repetition of mammography (P <0.05). Among the other variables studied, knowledge (β=-0.5) had the highest direct and significant impact on repetition of mammography (P <0.05). Family history of breast cancer was one of the predictors of repetition of mammography, but the results did not prove any relationship with risk perception. Further studies are needed to assess the effect of risk perception and knowledge about time interval on the initiation and continuation of mammography.

  14. ON THE MISALIGNMENT OF THE DIRECTLY IMAGED PLANET {beta} PICTORIS b WITH THE SYSTEM'S WARPED INNER DISK

    SciTech Connect

    Dawson, Rebekah I.; Murray-Clay, Ruth A.; Fabrycky, Daniel C.

    2011-12-10

    The vertical warp in the debris disk {beta} Pictoris-an inclined inner disk extending into a flat outer disk-has long been interpreted as the signpost of a planet on an inclined orbit. Direct images spanning 2004-2010 have revealed {beta} Pictoris b, a planet with a mass and orbital distance consistent with this picture. However, it was recently reported that the orbit of planet b is aligned with the flat outer disk, not the inclined inner disk, and thus lacks the inclination to warp the disk. We explore three scenarios for reconciling the apparent misalignment of the directly imaged planet {beta} Pictoris b with the warped inner disk of {beta} Pictoris: observational uncertainty, an additional planet, and damping of planet b's inclination. We find that, at the extremes of the uncertainties, the orbit of {beta} Pictoris b has the inclination necessary to produce the observed warp. We also find that if planet b were aligned with the flat outer disk, it would prevent another planet from creating a warp with the observed properties; therefore planet b itself must be responsible for the warp. Finally, planet b's inclination could have been damped by dynamical friction and still produce the observed disk morphology, but the feasibility of damping depends on disk properties and the presence of other planets. More precise observations of the orbit of planet b and the position angle of the outer disk will allow us to distinguish between the first and third scenarios.

  15. Collaborative essay testing: group work that counts.

    PubMed

    Gallagher, Peggy A

    2009-01-01

    Because much of a nurse's work is accomplished through working in groups, nursing students need an understanding of group process as well as opportunities to problem-solve in groups. Despite an emphasis on group activities as critical for classroom learning, there is a lack of evidence in the nursing literature that describes collaborative essay testing as a teaching strategy. In this class, nursing students worked together in small groups to answer examination questions before submitting a common set of answers. In a follow-up survey, students reported that collaborative testing was a positive experience (e.g., promoting critical thinking, confidence in knowledge, and teamwork). Faculty were excited by the lively dialog heard during the testing in what appeared to be an atmosphere of teamwork. Future efforts could include providing nursing students with direct instruction on group process and more opportunities to work and test collaboratively.

  16. Morbus-Locke's early essay on disease.

    PubMed

    Walmsley, J

    2000-01-01

    John Locke engaged in a systematic study of medicine from the late 1650's. In this period he acquainted himself with the three main competing natural philosophical theories of the time -Galenism, Paracelsianism and Mechanism. He was particularly interested in the work of Sennert, Helmont and Doyle. In 1666, just after the publication of Boyle's The Origine of Formes and Qualities, Locke wrote a short paper entitled Morbus. This paper gave Locke's own view of the nature of disease. Locke went out of his way to criticise Boyle's attempts to give mechanical explanations for biological phenomena. He endorsed Helmont's theory that disease was caused by "ferments" and "Archei" and re-introduced Galenic temperaments as factors of susceptibility in seminal diseases. Locke did not endorse a mechanical corpuscularianism at this stage in his career, when his contact with Boyle was most frequent. Consequently, Locke's espousal of the corpuscular philosophy in the Essay cannot be attributed to Locke's association with Boyle at this time.

  17. Winners of student essay contest receive awards

    NASA Technical Reports Server (NTRS)

    1999-01-01

    George Meguiar (left) presents a scholarship award to Kyla Davis Horn, of Cocoa Beach, one of the winners of an essay contest related to the 30th Anniversary of Apollo 11. Meguiar and George English (second from right) head the Apollo 11 Commemoration Association who sponsored the contest in conjunction with Florida Today newspaper. The other scholarship winner is Kyle Rukaczewski, of Satellite Beach (far right). A third winner, Jason Gagnon, of Viera, was unable to attend. The presentation was made at the Apollo/Saturn V Center during an anniversary banquet that honored all the people who made the Apollo Program possible. Special guests included former Apollo astronauts Neil Armstrong, Edwin 'Buzz' Aldrin, Gene Cernan and Walt Cunningham, who shared their experiences with the audience.

  18. Winners of student essay contest receive awards

    NASA Technical Reports Server (NTRS)

    1999-01-01

    At the Apollo/Saturn V Center, George Meguiar (center left) and George English (center right) present scholarships to two students who entered an essay contest in conjunction with the 30th Anniversary of Apollo 11. The winners shown are Kyla Davis Horn, of Cocoa Beach, and Kyle Rukaczewski, of Satellite Beach. A third winner, Jason Gagnon, of Viera, was unable to attend. Meguiar and English head the Apollo 11 Commemoration Association which sponsored the contest in conjunction with Florida Today newspaper. The presentation was made at the Apollo/Saturn V Center during an anniversary banquet that honored all the people who made the Apollo Program possible. Special guests included former Apollo astronauts Neil Armstrong, Edwin 'Buzz' Aldrin, Gene Cernan and Walt Cunningham, who shared their experiences with the audience.

  19. Jeremy Bentham's essay on "Paederasty". Part 2.

    PubMed

    Crompton, L

    1978-01-01

    This is Part 2 of a transcription of Bentham's manuscript essay on "Paederasty" (1785), Part 1 of which appeared in Vol. 3, No. 4. In Part 1 Bentham argued for the decriminalization of sodomy and opposed the theories of Montesquieu and Voltaire as to its social dangers. In Part 2 Bentham speculates on its causes and alleges that the real reason such behavior is so severely punished is an irrational "antipathy" to pleasure generally and to sexual pleasure in particular. He discusses the danger of blackmail and false accusations and the punishment of lesbian acts, bestiality, and masturbation. Some miscellaneous related notes by Bentham are appended: these deal with religious fears based on the destruction of Sodom, the threat to population, the harshness of English naval law, and other topics.

  20. Essays on New Careers; Social Implications for Adult Educators.

    ERIC Educational Resources Information Center

    Riessman, Frank; And Others

    These essays concentrate on the challenge that adult education faces in helping the urban poor develop meaningful paraprofessional careers in the human services. In one essay, the reformist approach to improving access to credentials is compared with the radical approach, which questions the validity of the credentials process as well as its…

  1. Missing: Electronic Feedback in Egyptian EFL Essay Writing Classes

    ERIC Educational Resources Information Center

    Seliem, Soheir; Ahmed, Abdelhamid

    2009-01-01

    EFL essay writing is considered one of the most important academic courses in the teacher education programmes that should help develop students' skills to write cohesively and coherently. Teachers' feedback plays a crucial role in improving and enhancing the quality of students' written essays. The aim of the current study was to shed light on…

  2. Meet the 2008 Cliff Weiss Memorial Essay Contest Winners

    ERIC Educational Resources Information Center

    Techniques: Connecting Education and Careers (J3), 2008

    2008-01-01

    This article presents the winners of the 2008 Cliff Weiss Memorial Essay Contest and their winning essays. The winners are Spencer Terry of Tulsa, Oklahoma (secondary), and Carrie Snyder-Renfro of Oklahoma City, Oklahoma (postsecondary). The topic for secondary students is "How would you communicate the impact and importance of CTE related to your…

  3. The Essay Test: A Look at the Advantages and Disadvantages.

    ERIC Educational Resources Information Center

    Tuckman, Bruce W.

    1993-01-01

    Essay tests are easily constructed, relatively valid assessments of higher cognitive processes but are harder to score reliably. Teachers using essay tests are advised to follow clearly designed objectives, construct all-inclusive, pilot-tested questions, develop a checklist of specific scoring points and a model answer for each question, and use…

  4. Communicating Evaluation Findings: The Use of a Chart Essay.

    ERIC Educational Resources Information Center

    Jones, B. Kathryn; Mitchell, Napoleon

    1990-01-01

    The experience of the Dallas (Texas) Independent School District in using a policy-oriented report (the chart essay), rather than using a methods-oriented report, to communicate evaluation findings is described. Resulting changes in the research and evaluation department, and implications of use of a chart essay are discussed. (SLD)

  5. Revisiting the Personal Essay with Ben Hamper's "Rivethead"

    ERIC Educational Resources Information Center

    Kramer, Jacob

    2011-01-01

    The personal essay--a paper in which a student brings in his or her own experience or concerns--is probably familiar to most historians. Teaching at the City University of New York, the author has found grading personal essays somewhat perplexing. They are sometimes written in response to an assignment that does not call for personal reflection.…

  6. Performance, Feedback, and Revision: Metacognitive Approaches to Undergraduate Essay Writing

    ERIC Educational Resources Information Center

    Riddell, Jessica

    2015-01-01

    This paper explores ways in which frequent feedback and clear assessment criteria can improve students' essay writing performance in a first-year English literature course. Students (n = 68) completed a series of three scaffolded exercises over the course of a semester, where they evaluated undergraduate essays using a predetermined assessment…

  7. An Essay on Pedagogy by Mikhail M. Bakhtin

    ERIC Educational Resources Information Center

    Bazerman, Charles

    2005-01-01

    This is an extended summary of a pedagogic essay by Mikhail M. Bakhtin on writing style, titled "Dialogic Origin and Dialogic Pedagogy of Grammar: Stylistics as Part of Russian Language Instruction in Secondary School." In this essay, written in spring 1945 while Bakhtin was a secondary school teacher of Russian language arts, he argues that every…

  8. The Great Excluded: Critical Essays on Children's Literature. Volume One.

    ERIC Educational Resources Information Center

    Butler, Francelia, Ed.

    This collection of essays is intended to stimulate writing, teaching, and study of children's literature by humanists. Among the essays are: "Aesop as Litmus: The Acid Test of Children's Literature,""Children's Literature in Old English,""Children's Literature in the Middle Ages,""Pilgrim's Progress as Fairy Tale,""Out of the Ordinary Road: Locke…

  9. Literacy, Language and Community Publishing. Essays in Adult Education.

    ERIC Educational Resources Information Center

    Mace, Jane, Ed.

    This book contains an introduction and 11 essays describing reading and writing projects in which adult literacy learners enrolled in the following types of programs participated: adult literacy and/or language classes, refugee groups, oral history and reminiscence projects, and community publishing and writing workshops. The following essays are…

  10. How Important Is Content in the Ratings of Essay Assessments?

    ERIC Educational Resources Information Center

    Shermis, Mark D.; Shneyderman, Aleksandr; Attali, Yigal

    2008-01-01

    This study was designed to examine the extent to which "content" accounts for variance in scores assigned in automated essay scoring protocols. Specifically it was hypothesised that certain writing genre would emphasise content more than others. Data were drawn from 1668 essays calibrated at two grade levels (6 and 8) using "e-rater[TM]", an…

  11. Performance of a Generic Approach in Automated Essay Scoring

    ERIC Educational Resources Information Center

    Attali, Yigal; Bridgeman, Brent; Trapani, Catherine

    2010-01-01

    A generic approach in automated essay scoring produces scores that have the same meaning across all prompts, existing or new, of a writing assessment. This is accomplished by using a single set of linguistic indicators (or features), a consistent way of combining and weighting these features into essay scores, and a focus on features that are not…

  12. Automated Essay Scoring With e-rater[R] V.2

    ERIC Educational Resources Information Center

    Attali, Yigal; Burstein, Jill

    2006-01-01

    E-rater[R] has been used by the Educational Testing Service for automated essay scoring since 1999. This paper describes a new version of e-rater (V.2) that is different from other automated essay scoring systems in several important respects. The main innovations of e-rater V.2 are a small, intuitive, and meaningful set of features used for…

  13. The Word for Teaching Is Learning: Essays for James Britton.

    ERIC Educational Resources Information Center

    Lightfoot, Martin, Ed.; Martin, Nancy, Ed.

    Reflecting the influence of James Britton in the field of language and learning, this book--a collection of essays by researchers and practitioners in the area of language and learning--focuses on recent issues of language development in learning. The book contains the following 27 essays: (1) "Social Interaction as Scaffold: The Power and…

  14. Designing Essay Questions for Different Levels of Learning.

    ERIC Educational Resources Information Center

    McDaniel, Thomas R.

    1979-01-01

    Proposes that college teachers in most of the academic disciplines teach students to write essays in their given subject matter area. Bloom's "Taxonomy of Educational Objectives" is offered as a guide to organizing instruction and student learning around the demands of well-constructed essay questions. Sample questions and classroom…

  15. Automated Scoring of Chinese Engineering Students' English Essays

    ERIC Educational Resources Information Center

    Liu, Ming; Wang, Yuqi; Xu, Weiwei; Liu, Li

    2017-01-01

    The number of Chinese engineering students has increased greatly since 1999. Rating the quality of these students' English essays has thus become time-consuming and challenging. This paper presents a novel automatic essay scoring algorithm called PSOSVR, based on a machine learning algorithm, Support Vector Machine for Regression (SVR), and a…

  16. History.edu: Essays on Teaching with Technology.

    ERIC Educational Resources Information Center

    Trinkle, Dennis A., Ed.; Merriman, Scott A., Ed.

    Intended to be equally useful to high school and college instructors, this book contains studies in history pedagogy, among them the first three published essays measuring qualitatively and quantitatively the successes and failures of "e-teaching" and distance learning. Collectively, the essays urge instructors to take the next step with…

  17. A Crosscultural Analysis of Argumentative Strategies in Student Essays.

    ERIC Educational Resources Information Center

    Kamimura, Taeko; Oi, Kyoko

    A study of essays on a single topic (capital punishment) written by 22 American high school students and 30 second-year Japanese college students investigated: cultural differences in organizational patterns in argumentative essays; comparative use of rational and affective appeals; differences in content of rational and affective appeals;…

  18. Automatically Scoring Short Essays for Content. CRESST Report 836

    ERIC Educational Resources Information Center

    Kerr, Deirdre; Mousavi, Hamid; Iseli, Markus R.

    2013-01-01

    The Common Core assessments emphasize short essay constructed response items over multiple choice items because they are more precise measures of understanding. However, such items are too costly and time consuming to be used in national assessments unless a way is found to score them automatically. Current automatic essay scoring techniques are…

  19. Teaching Composition: Twelve Bibliographical Essays. Revised and Enlarged Edition.

    ERIC Educational Resources Information Center

    Tate, Gary, Ed.

    Intended for teachers of composition courses, this book provides twelve bibliographic essays covering various aspects of composition studies. The list of essays are as follows: (1) "Recent Developments in Rhetorical Invention" (Richard Young); (2) "Structure and Form in Non-Narrative Prose" (Richard L. Larson); (3)…

  20. Two-Year College English: Essays for a New Century.

    ERIC Educational Resources Information Center

    Reynolds, Mark, Ed.

    Noting that the nearly 1,400 two-year colleges in the United States enroll almost half of all students in higher education, this collection of essays discusses the students, the curriculum, and the faculty at these colleges. In essence, the collection surveys what is "on the minds" of two-year college English teachers. The essays and…