WorldWideScience

Sample records for histiocytosis fascinating dynamics

  1. HISTIOCYTOSIS X: CLINICAL OBSERVATIONS

    Directory of Open Access Journals (Sweden)

    E. Y. Ponomareva

    2012-01-01

    Full Text Available Two clinical cases of pulmonary Langerhans cell histiocytosis X have been analyzed demonstrating lung and other inner organ pathology, common clinical and X-ray features but different life prognosis.

  2. Las histiocitosis Histiocytosis

    Directory of Open Access Journals (Sweden)

    Eva Svarch

    2001-12-01

    Full Text Available El término histiocitosis identifica un grupo de alteraciones que tienen en común la proliferación de células dendríticas (CD y los macrófagos, y se diagnostican más frecuentemente en niños. Dentro de las relacionadas con las CD las fundamentales son las histiocitosis a células de Langerhans (HCL. Las HCL tienen un comportamiento clínico muy variable, que puede ir desde una lesión que involucra un solo sitio o sistema hasta una enfermedad multisistémica. El tratamiento depende de la extensión del proceso. Una lesión única tiende a desaparecer espontáneamente. También la biopsia diagnóstica con o sin inyección de un esteroide puede iniciar la curación. Los pacientes con enfermedad multisistémica pueden beneficiarse con el tratamiento esteroideo y citostático o inclusive con el trasplante de células progenitoras hematopoyéticas. La histiocitosis sinusal con linfoadenopatías masivas o enfermedad de Rosai Dorfman se debe a la proliferación de los macrófagos, es de naturaleza benigna y usualmente autolimitada. Afecta sobre todo a niños y adultos jóvenes. La linfohistiocitosis hemofagocítica también se produce por la proliferación de los macrófagos y es una enfermedad rara con una alta mortalidad. Puede ser familiar (autosómica recesiva o secundaria a infecciones virales. Esta última forma se presenta más frecuentemente en el lactante pequeño. En la actualidad, sobre todo en la variedad familiar, el trasplante alogénico de células progenitoras hematopoyéticas puede ser la única medida curativaThe term histiocytosis identifies a group of disorders that have in common the proliferation of dentritic cells (DC and macrophages and is frequently diagnosed in children. Among the fundamental variants of histiocytosis related with DC, we find Langerhans cell histiocytosis (LCH. Langerhans cell histiocytosis has very variable clinical behavior that ranges from a lesion involving only one site or system to a multisystem

  3. Pulmonary langerhans cell histiocytosis

    Directory of Open Access Journals (Sweden)

    Suri Harpreet S

    2012-03-01

    Full Text Available Abstract Pulmonary Langerhans Cell Histiocytosis (PLCH is a relatively uncommon lung disease that generally, but not invariably, occurs in cigarette smokers. The pathologic hallmark of PLCH is the accumulation of Langerhans and other inflammatory cells in small airways, resulting in the formation of nodular inflammatory lesions. While the overwhelming majority of patients are smokers, mechanisms by which smoking induces this disease are not known, but likely involve a combination of events resulting in enhanced recruitment and activation of Langerhans cells in small airways. Bronchiolar inflammation may be accompanied by variable lung interstitial and vascular involvement. While cellular inflammation is prominent in early disease, more advanced stages are characterized by cystic lung destruction, cicatricial scarring of airways, and pulmonary vascular remodeling. Pulmonary function is frequently abnormal at presentation. Imaging of the chest with high resolution chest CT scanning may show characteristic nodular and cystic abnormalities. Lung biopsy is necessary for a definitive diagnosis, although may not be required in instances were imaging findings are highly characteristic. There is no general consensus regarding the role of immunosuppressive therapy in smokers with PLCH. All smokers must be counseled on the importance of smoking cessation, which may result in regression of disease and obviate the need for systemic immunosuppressive therapy. The prognosis for most patients is relatively good, particularly if longitudinal lung function testing shows stability. Complications like pneumothoraces and secondary pulmonary hypertension may shorten life expectancy. Patients with progressive disease may require lung transplantation.

  4. Radiologic features in histiocytosis syndrome

    International Nuclear Information System (INIS)

    Hong, Sung Mo; Cho, Byung Jae; Yeon, Kyung Mo

    1980-01-01

    Histiocytosis syndrome is not rare disease of unknown etiology, characterized by development of granulomatous lesions with histiocytic proliferation. Authors analyzed 22 cases, which had been confirmed as histiocytosis syndrome from 1971 to Feb. 1980 with special attention to 15 cases showing positive findings on radiological examinations. The results are as follows. 1. Overall male to female ratio was about 2:1. The majority were between 1 and 7 years of age. 2. Skeletal system was involved in orders as follows: skull, pelvis, femur, rib, spine. 3. Four cases of pulmonary involvement were experienced. All cases had interstitial involvement with reticulonodular densities on roentgenograms. 4. We had experienced a pituitary tumor, presumably localized histiocytic mass, in a patient with diabetes insipidus. 5. In long bone involvement, diaphysis or metaphysis was usually involved, but in one patient, lesion were extended into epiphysis. 6. One case of platyspondyly was found, with symmetrical compression

  5. Radiologic features in histiocytosis syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Sung Mo; Cho, Byung Jae; Yeon, Kyung Mo [College of Medicine, Seoul National University, Seoul (Korea, Republic of)

    1980-12-15

    Histiocytosis syndrome is not rare disease of unknown etiology, characterized by development of granulomatous lesions with histiocytic proliferation. Authors analyzed 22 cases, which had been confirmed as histiocytosis syndrome from 1971 to Feb. 1980 with special attention to 15 cases showing positive findings on radiological examinations. The results are as follows. 1. Overall male to female ratio was about 2:1. The majority were between 1 and 7 years of age. 2. Skeletal system was involved in orders as follows: skull, pelvis, femur, rib, spine. 3. Four cases of pulmonary involvement were experienced. All cases had interstitial involvement with reticulonodular densities on roentgenograms. 4. We had experienced a pituitary tumor, presumably localized histiocytic mass, in a patient with diabetes insipidus. 5. In long bone involvement, diaphysis or metaphysis was usually involved, but in one patient, lesion were extended into epiphysis. 6. One case of platyspondyly was found, with symmetrical compression.

  6. Pulmonary fibrosis caused by histiocytosis X

    International Nuclear Information System (INIS)

    Reinbold, W.D.; Seemann, W.R.; Ruehle, K.H.

    1984-01-01

    This paper reports on a 23-year-old man suffering from pulmonary fibrosis caused by localised histiocytosis X. Although chest film examination shows diffuse pulmonary involvement the patient is asymptomatic. No other organ systems are involved. The different forms and prognosis of histiocytosis X are discussed. (orig.)

  7. Monoubiquitination Inhibits the Actin Bundling Activity of Fascin.

    Science.gov (United States)

    Lin, Shengchen; Lu, Shuang; Mulaj, Mentor; Fang, Bin; Keeley, Tyler; Wan, Lixin; Hao, Jihui; Muschol, Martin; Sun, Jianwei; Yang, Shengyu

    2016-12-30

    Fascin is an actin bundling protein that cross-links individual actin filaments into straight, compact, and stiff bundles, which are crucial for the formation of filopodia, stereocillia, and other finger-like membrane protrusions. The dysregulation of fascin has been implicated in cancer metastasis, hearing loss, and blindness. Here we identified monoubiquitination as a novel mechanism that regulates fascin bundling activity and dynamics. The monoubiquitination sites were identified to be Lys 247 and Lys 250 , two residues located in a positive charge patch at the actin binding site 2 of fascin. Using a chemical ubiquitination method, we synthesized chemically monoubiquitinated fascin and determined the effects of monoubiquitination on fascin bundling activity and dynamics. Our data demonstrated that monoubiquitination decreased the fascin bundling EC 50 , delayed the initiation of bundle assembly, and accelerated the disassembly of existing bundles. By analyzing the electrostatic properties on the solvent-accessible surface of fascin, we proposed that monoubiquitination introduced steric hindrance to interfere with the interaction between actin filaments and the positively charged patch at actin binding site 2. We also identified Smurf1 as a E3 ligase regulating the monoubiquitination of fascin. Our findings revealed a previously unidentified regulatory mechanism for fascin, which will have important implications for the understanding of actin bundle regulation under physiological and pathological conditions. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  8. Monoubiquitination Inhibits the Actin Bundling Activity of Fascin*

    Science.gov (United States)

    Lin, Shengchen; Lu, Shuang; Mulaj, Mentor; Fang, Bin; Keeley, Tyler; Wan, Lixin; Hao, Jihui; Muschol, Martin; Sun, Jianwei; Yang, Shengyu

    2016-01-01

    Fascin is an actin bundling protein that cross-links individual actin filaments into straight, compact, and stiff bundles, which are crucial for the formation of filopodia, stereocillia, and other finger-like membrane protrusions. The dysregulation of fascin has been implicated in cancer metastasis, hearing loss, and blindness. Here we identified monoubiquitination as a novel mechanism that regulates fascin bundling activity and dynamics. The monoubiquitination sites were identified to be Lys247 and Lys250, two residues located in a positive charge patch at the actin binding site 2 of fascin. Using a chemical ubiquitination method, we synthesized chemically monoubiquitinated fascin and determined the effects of monoubiquitination on fascin bundling activity and dynamics. Our data demonstrated that monoubiquitination decreased the fascin bundling EC50, delayed the initiation of bundle assembly, and accelerated the disassembly of existing bundles. By analyzing the electrostatic properties on the solvent-accessible surface of fascin, we proposed that monoubiquitination introduced steric hindrance to interfere with the interaction between actin filaments and the positively charged patch at actin binding site 2. We also identified Smurf1 as a E3 ligase regulating the monoubiquitination of fascin. Our findings revealed a previously unidentified regulatory mechanism for fascin, which will have important implications for the understanding of actin bundle regulation under physiological and pathological conditions. PMID:27879315

  9. Fascination of chaos

    International Nuclear Information System (INIS)

    Loskutov, Alexander

    2010-01-01

    This review introduces most of the concepts used in the study of chaotic phenomena in nonlinear systems and has as its objective to summarize the current understanding of results from the theory of chaotic dynamical systems and to describe the original ideas underlying the study of deterministic chaos. The presentation relies on informal analysis, with abstract mathematical ideas visualized geometrically or by examples from physics. Hyperbolic dynamics, homoclinic trajectories and tangencies, wild hyperbolic sets, and different types of attractors which appear in dynamical systems are considered. The key aspects of ergodic theory are discussed, and the basic statistical properties of chaotic dynamical systems are described. The fundamental difference between stochastic dynamics and deterministic chaos is explained. The review concludes with an investigation of the possibility of studying complex systems on the basis of the analysis of registered signals, i.e. the generated time series. (reviews of topical problems)

  10. Histiocytosis X | Mohammed | Annals of African Medicine

    African Journals Online (AJOL)

    Histiocytosis X (Langerhan's cell granulomatosis) is a disease of unknown aetiology, but viral origin has been implicated.1 It is a clinicopathologic entity characterized by proliferation of Langerhan's cell (which are not primarily phagocytic) in an appropriate milieu.2 ...

  11. Cerebellar leukoencephalopathy: most likely histiocytosis-related

    NARCIS (Netherlands)

    van der Knaap, M.S.; Arts, W.F.M.; Garbern, J.Y.; Hedlund, G.; Winkler, F.; Barbosa, C.; King, M.D.; Bjornstad, A.; Hussain, N.; Beyer, M.K.; Gomez, C.; Patterson, M.C.; Grattan-Smith, P.; Timmons, M.; van der Valk, P.

    2008-01-01

    Background: Histiocytosis, both Langerhans and non-Langerhans cell type, can be associated with cerebellar white matter abnormalities, thought to be paraneoplastic. The associated clinical picture consists of ataxia, spasticity, and cognitive decline. Hormonal dysfunction is frequent. MRI shows

  12. Fascinating Organic Molecules from Nature

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 18; Issue 5. Fascinating Organic Molecules from Nature - Using a Natural ... Road Banashankari 2nd Stage Bangalore 560 070, India. Department of Chemistry Sri Sathya Sai Institute of Higher Learning Brindavan Campus Bangalore 560 067, India.

  13. Fascinating Organic Molecules from Nature

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 18; Issue 7. Fascinating Organic Molecules from Nature - Sweet Stimulants of ... Road Banashankari 2nd Stage Bangalore 560 070, India. Department of Chemistry Sri Sathya Sai Institute of Higher Learning Brindavan Campus Bangalore 560 067, India.

  14. [Langerhans cell histiocytosis in adults].

    Science.gov (United States)

    Néel, A; Artifoni, M; Donadieu, J; Lorillon, G; Hamidou, M; Tazi, A

    2015-10-01

    Langerhans cell histiocytosis (LCH) is a rare disease characterized by the infiltration of one or more organs by Langerhans cell-like dendritic cells, most often organized in granulomas. The disease has been initially described in children. The clinical picture of LCH is highly variable. Bone, skin, pituitary gland, lung, central nervous system, lymphoid organs are the main organs involved whereas liver and intestinal tract localizations are less frequently encountered. LCH course ranges from a fulminant multisystem disease to spontaneous resolution. Several randomized controlled trials have enable pediatricians to refine the management of children with LCH. Adult LCH has some specific features and poses distinct therapeutic challenges, knowing that data on these patients are limited. Herein, we will provide an overview of current knowledge regarding adult LCH and its management. We will also discuss recent advances in the understanding of the disease, (i.e. the role of BRAF oncogene) that opens the way toward targeted therapies. Copyright © 2015 Société nationale française de médecine interne (SNFMI). Published by Elsevier SAS. All rights reserved.

  15. Two rare cases of laryngeal intralymphatic histiocytosis

    DEFF Research Database (Denmark)

    Reznitsky, Martin; Daugaard, Søren; Charabi, Birgitte Wittenborg

    2016-01-01

    We report two rare cases of intralymphatic histiocytosis causing, respectively, recurrent and persistent episodes of upper airway swelling and breathing difficulties. Case 1 was a 39-year-old man who was referred with recurrent upper airway swelling causing difficulty in breathing. A direct....... Extensive investigations were performed but discovered no abnormal findings. He received CO2 laser treatment twice and the swelling decreased. Intralymphatic histiocytosis is extremely rare in upper airway pathology. It is an important differential diagnosis in patients with recurrent and chronic laryngeal...

  16. Langerhans Cell Histiocytosis Involving Maxilla and Mandible

    Directory of Open Access Journals (Sweden)

    M. Guna Shekhar

    2009-06-01

    Full Text Available Langerhans cell histiocytosis is a relatively rare unique disease process characterized by an abnormal proliferation of immature dendritic cells usually affecting children and young adults. Jaws are involved in less than 10% of children with the disease while mandibular involvement in young children is uncommon and bilateral affection is very rare. The purpose of this report is to describe a unique and very rare case of simultaneous and bilateral occurrence of Langerhans cell histiocytosis in both the jaws of a four-year-old boy.

  17. Pulmonary histiocytosis X - imaging aspects of pulmonary involvement

    International Nuclear Information System (INIS)

    Sabedotti, Ismail Fernando; Maeda, Lucimara; Ferreira, Daniel Miranda; Montandon, Cristiano; Marins, Jose Luiz C.

    1999-01-01

    Pulmonary histiocytosis X is an idiopathic disease which is and uncommon but important cause of pulmonary fibrosis in young adults. Chest radiographs and high resolution computed tomographic (HRCT) scans of the lungs of 7 patients diagnosed as pulmonary histiocytosis X were examined retrospectively. The authors reviewed the pathologic, clinical and radiographic features of pulmonary histiocytosis X, focusing on differential diagnosis and disease progression. Pulmonary histiocytosis X can be suspected on the basis of chest radiographic findings; predominantly upper lobe nodules and cysts present an increased sensitivity and are virtually pathognomonic of this disorder. Chest HRCT allows good assessment of the evolution of pulmonary histiocytosis X and is also valuable in distinguishing histiocytosis from other disorders that produces nodules or cysts. (author)

  18. Partial hypopituitarism and Langerhans cell histiocytosis

    Science.gov (United States)

    Balaguruswamy, S; Chattington, P D

    2011-01-01

    A case of multisystem Langerhans cell histiocytosis with pituitary involvement nearly 20 years after initial presentation. A 48-year-old man had histiocytosis X 22 years ago initially involving the groin; subsequently his external auditory meatus, scalp, gum, mandibular bone, perineum and axilla were involved and treated. The pituitary gland was involved 4 years ago. A thyrotropin-releasing hormone test showed delayed response suggestive of hypothalamic disease. Prolactin levels were normal. A gonadotropin-releasing hormone test showed impaired testosterone and gonadotrophin response in keeping with pituitary disease. A glucagon stimulation test showed an impaired growth hormone response but a normal cortisol increase. MRI pituitary showed an empty sella. There was no evidence of diabetes insipidus. Bone mineral densitometry was normal. He has partial hypopituitarism needing thyroxine and testosterone replacement. He also developed type 2 diabetes mellitus 9 years ago. He is closely monitored for any development of diabetes insipidus and the need for growth hormone supplementation. PMID:22715201

  19. Paediatric neuroradiological aspects of Langerhans cell histiocytosis

    Energy Technology Data Exchange (ETDEWEB)

    Demaerel, Philippe [University Hospital K.U.Leuven, Department of Radiology, Leuven (Belgium); Gool, Stefaan van [University Hospital K.U.Leuven, Paediatric Haemato-oncology/Neuro-oncology, Leuven (Belgium)

    2008-01-15

    Langerhans cell histiocytosis, previously known as histiocytosis X, is a complex disease consisting of three entities that are all characterized by a proliferation of the Langerhans cell. The clinical course is variable and ranges from a solitary lytic bone or skin lesion with complete remission to a multisystem disorder with possible lethal outcome. The clinical suspicion can be increased based on radiological findings that are important criteria in defining the extent of the disease involvement. A biopsy is often necessary for establishing the final diagnosis. The lytic craniofacial bone lesions are the most common craniospinal abnormality in Langerhans cell histiocytosis. Abnormalities in the hypothalamic-pituitary region are the most frequent manifestations, often accompanied with diabetes insipidus as the presenting symptom. A range of different central nervous system abnormalities can be recognized. It is important to be able to recognize the extensive spectrum of neuroradiological abnormalities in order to arrive at the diagnosis. Neuroimaging plays an even more important role in assessing the response to treatment or possible relapse. (orig.)

  20. A Rare Disease in Adult: Langerhans Cell Histiocytosis

    Science.gov (United States)

    Berber, Ilhami; Erkurt, Mehmet Ali; Kuku, Irfan; Koroglu, Mustafa; Kaya, Emin; Unlu, Serkan

    2013-01-01

    Langerhans cell histiocytosis is a rare histiocytic disorder and has been diagnosed in all age groups, but is most common in children. This disease is very rare in adults. We presented a patient who was 62 years old man diagnosed langerhans cell histiocytosis. PMID:29147350

  1. Liver involvement in Langerhans cell histiocytosis

    International Nuclear Information System (INIS)

    Wong, Adelaine; Ortiz-Neira, Clara L.; Abou Reslan, Walid; Kaura, Deepak; Sharon, Raphael; Anderson, Ronald; Pinto-Rojas, Alfredo

    2006-01-01

    Liver involvement in Langerhans cell histiocytosis (LCH) typically presents with hepatomegaly and other signs of liver dysfunction. We present an 11-month-old child having only minimally elevated liver enzymes as an indication of liver involvement. Using sonography as the initial diagnostic tool followed by MRI, LCH of the liver was revealed. A review of sonographic, CT, MRI and MR cholangiopancreatography findings in liver LCH is presented. We recommend that physicians consider sonography and MRI screening for liver involvement in patients with newly diagnosed LCH, as periportal involvement may be present with little or no liver function abnormality present, as in this patient. (orig.)

  2. Liver involvement in Langerhans' cell histiocytosis. Case report.

    Science.gov (United States)

    Dina, Ion; Copaescu, Catalin; Herlea, Vlad; Wrba, Fritz; Iacobescu, Claudia

    2006-03-01

    Langerhans'cell histiocytosis (Histiocytosis X) is a rare disease of unknown cause characterized by oligoclonal proliferation of Langerhans cells. It occurs mostly in children and young adults and involves one or more body systems such as bone, hypothalamus, posterior pituitary gland, lymph nodes, liver or various soft tissues. The diagnosis is always made by a histological approach. We report a case of Langerhans'cell histiocytosis in a young patient with clinical signs of diabetes insipidus and hepatic involvement in whom the immunohistochemical analysis of the liver tissue led to the definitive diagnosis.

  3. Thoracolumbar Langerhans cell histiocytosis in a toddler

    Directory of Open Access Journals (Sweden)

    Zhi Gang Lan

    2018-01-01

    Full Text Available Introduction: Langerhans cell histiocytosis (LCH is a rare uni or multisystem disorder associated with extreme production of immunoreactive Langerhans cells. Although this disorder has been reported in all age groups, spinal involvement especially thoracolumbar spine is seldom reported in toddlers. Case presentation: We present a one (1 year, four (4 months female child with a history of recurrent fever, irritability and severe anemia of one (1 month duration. CT-scan and MRI revealed a collapsed twelfth thoracic vertebra (T12 body height greater than 95% with a huge intradural soft tissue mass. T12 cortectomy via posterior thoracolumbar approach was used to decompress the soft tissue part followed by interbody fusion with titanium cage filled with autologous iliac crest bone graft, fixation using plates and screws. Conclusion: We are of the view that surgical decompression of spinal LHC lesions with interbody fusion with titanium cage filled with autologous iliac crest bone graft and fixation using plates and screws is very crucial in relieving neurological deficits. However, the patient will need repeated surgeries as she advances with age in a timely manner to avert any neurological deficit that may occur. Keywords: Langerhans cell histiocytosis (LCH, Letterer-Siwe disease, Hand-Schüller-Christian disease, Eosinophilic granuloma

  4. Conventional radiology in the bony compromise of Langerhans cells Histiocytosis

    International Nuclear Information System (INIS)

    Morales, Nilson; Gonzalez, Claudia Patricia; Melendez, Patricia; Terselich, Gretty

    1999-01-01

    We present a descriptive study of 47 patients who attended the National Cancer Institute in Bogota, Colombia with pathological diagnosis of Langerhans cell histiocytosis. We reviewed the most frequent conventional x-ray findings

  5. Aspects of pulmonary histiocytosis X on high resolution computed tomography

    International Nuclear Information System (INIS)

    Costa, N.S.S.; Castro Lessa Angela, M.T. de; Angelo Junior, J.R.L.; Silva, F.M.D.; Kavakama, J.; Carvalho, C.R.R. de; Cerri, G.G.

    1995-01-01

    Pulmonary histiocytosis X is a disease that occurs in young adults and presents with nodules and cysts, mainly in upper lobes, with consequent pulmonary fibrosis. These pulmonary changes are virtually pathognomonic findings on high resolution computed tomography, that allows estimate the area of the lung involved and distinguish histiocytosis X from other disorders that also produces nodules and cysts. (author). 10 refs, 2 tabs, 6 figs

  6. Langerhans' cell histiocytosis presenting with an intracranial epidural hematoma

    International Nuclear Information System (INIS)

    Lee, K.-W.; McLeary, M.S.; Zuppan, C.W.; Won, D.J.

    2000-01-01

    An 8-year-old boy developed vomiting and severe headache following minor head trauma. A CT scan of the head demonstrated a lytic lesion of the skull and adjacent epidural hematoma. Surgical evacuation and removal of the skull lesion and hematoma were carried out, and pathologic evaluation resulted in a diagnosis of Langerhans' cell histiocytosis (LCH). Epidural involvement of Langerhans' cell histiocytosis is very rare, and we report the first case of LCH presenting as an intracranial epidural hematoma. (orig.)

  7. Histiocytosis X: Scintigraphic and roentgenological findings

    International Nuclear Information System (INIS)

    Fezoulidis, I.; Wickenhauser, J.; Schurawitzki, H.; Gritzmann, N.

    1987-01-01

    The aim of this study was to compare the roentgenological and scintigraphic osseous changes in 25 resp. 18 patients with histiocytosis X and to analyse them. In particular, it was also interesting to discuss the divergent reports in the literature in respect of scintigraphic storage behaviour. In all patients examined before initiation of therapy (39 osseous foci) high activities were found scintigraphically. The extension of the scintigraphically active zone was much greater than the corresponding translucencies on the X-ray film. On the other hand, patients after therapy still showed foci on the X-ray film whereas the scan had already become inactive. This striking discrepancy between scan findings before and after therapy could be one of the reasons for divergent literature reports on this problem. (orig.) [de

  8. Malignant histiocytosis in childhood: morphologic considerations.

    Science.gov (United States)

    Jurco, S; Starling, K; Hawkins, E P

    1983-12-01

    Eight cases diagnosed over a ten-year period as malignant histiocytosis (MH; histiocytic medullary reticulosis) were reviewed to clarify diagnostic criteria for the childhood disease and to identify sources of diagnostic confusion. Five of the eight cases met the authors' criteria for diagnosis; i.e., they were characterized by loose mixed infiltrates composed of three cell types--well-differentiated histiocytes, prohistiocytes, and malignant histiocytes--and they had no leukemic phase. Three cases did not share these features and were reclassified. The liver was found to be the organ most useful in premortem diagnosis, and immunoperoxidase staining for immunoglobulins and lysozyme was also helpful. The clinical and morphologic features of the five cases confirm the authors' view that diagnoses of MH should be limited to cases in which there is a loose pleomorphic population of all three types of histiocytes and that cases with monomorphous populations of aggregated malignant cells should be classified as lymphomas.

  9. Intralymphatic Histiocytosis: A Report of 2 Cases.

    Science.gov (United States)

    Gómez-Sánchez, M E; Azaña-Defez, J M; Martínez-Martínez, M L; López-Villaescusa, M T

    Intralymphatic histiocytosis is a benign condition characterized by poorly defined erythematous plaques (sometimes forming a reticular pattern) as well as the presence of nodules and vesicles. Its etiology and pathogenesis appear to be related to chronic inflammation in the affected area, prior surgery, or systemic disease, particularly rheumatoid arthritis. We report on 2 new cases, both associated with joint surgery in the affected area and osteoarticular disease (primary synovial osteochondromatosis and rheumatoid arthritis). This is a chronic disease and there is no specific treatment. Different treatment options were chosen in the 2 cases described. A spectacular response to treatment with oral pentoxifylline and topical tacrolimus was observed in 1 of the patients. Copyright © 2017 AEDV. Publicado por Elsevier España, S.L.U. All rights reserved.

  10. Radiological signs of childhood Langerhans cell histiocytosis

    International Nuclear Information System (INIS)

    Mas, F.; Menor, F.; Moreno, A.; Vallcanera, A.; Esteban, M.J.; Muro, D.; Cortina, H.

    1997-01-01

    To describe the most prominent radiological sings of Langerhans cell histiocytosis (LCH) in childhood and review the general aspects of greatest interest to the general radiologist. The clinical and radiological histories of 40 children diagnosed on the basis of biopsy and/or cytology as having LCH in our center over a 16-year period were reviewed. Bone involvement was observed in 95% of patients; flat bones were affected in 95% of the cases, most frequently the cranium. Radiological changes in temporal bone were viewed in 15% of cases. There were long-bone lesions in 21% of the patients, involving, metaphyseal-diaphyseal bones in every case; multiple epiphyseal dysplasia was found in one and a purely cortical lesion in another. Vertebral involvement was detected in 18% of patients. Clinical evidence of diabetes insipidus (DI) was present in 22.5% of cases, while there were clinical or radiological signs of lung involvement in 15%. Bone involvement is the most common association reported in childhood LCH and is usually the reason for medical consultation. The flat bones, especially the cranium, are those most often affected. Diagnosis and follow-up studies are mainly based on plain radiography. DI due to hypothalamic infiltration in usually associated with normal CT scan. Lung involvement, uncommon in pediatric patients, is the major clinical and radiological difference with respect to the adult form. (Author) 33 refs

  11. CT manifestations of pulmonary Langerhans cell histiocytosis

    International Nuclear Information System (INIS)

    Qiang Jun; Yu Wei; Gao Wanqin; Song Haiqiao; Ma Yingjian

    2010-01-01

    Objective: To analyzes the CT manifestations of pulmonary Langerhans cell histiocytosis (PLCH). Methods: CT features of 11 patients with PLCH proved pathologically were analyzed retrospectively. Results: The main findings in 11 PLCHs were cysts and nodules. Two cases only had cysts, and 1 only had nodules, which most had cavitations. The other 8 cases showed cysts and nodules with 4 cases mainly manifested with cysts and nine mainly manifested with nodules. Two cases had pulmonary interstitial changes. One case only had cysts in the left upper lung field and 10 cases had lesions not only in the upper and middle but in the lower lung field, which 2 cases had more lesions in the lower and costo-phrenic angle field and 8 cases had less lesions in the costo-phrenic angle field. Three of these 8 cases had more lesions in the superior lobe and apical segment of lower lobe. Conclusion: CT manifestations of PLCH are helpful for the early diagnosis. (authors)

  12. CT findings of orbital langerhans cell histiocytosis

    International Nuclear Information System (INIS)

    Yi, Gina; Yoon, Hye Kyung; Han, Bokyung Kim; Kim, Kyeong Ah; Choo, In Wook

    2000-01-01

    To evaluate the CT findings in patients with Langerhans cell histiocytosis (LCH) involving the orbit. Orbital CT scans of six children with pathologically proven LCH were retrospectively analyzed. Follow-up CT (n=3D5) and MR (n=3D1) imaging findings were also reviewed. Initial CT scans revealed varying degree of bone destruction with soft-tissue masses, and on nonenhanced images the mean attenuation value was 44 Hounsfield units (HU). All masses showed mild to moderate enhancement with a mean attenuation value of 74 HU. The bony margins abutting onto soft tissue masses were irregular but clearly demarcated. No evidence of calcification or periosteal reaction was noted. Suprasellar mass and rib involvement was noted in one patient and hepatosplenomegaly in two. Follow-up CT and MR images showed that the soft tissue masses were almost completely resolved, with bone remodeling and reossification. A soft tissue mass with irregular but clearly demarcated bone destruction is thought to be a characteristic finding of LCH involving the orbit. Follow-up images after treatment showed bone remodeling and reossification. (author)

  13. Langerhans cell histiocytosis with involvement of the pons: case report

    Energy Technology Data Exchange (ETDEWEB)

    Vourtsi, A. [Xatzopoulou, Athens (Greece)]|[Department of Radiology, University of Athens Medical School, Athens (Greece); Papadopoulos, A.; Moulopoulos, L.A.; Vlahos, L. [Department of Radiology, University of Athens Medical School, Athens (Greece); Xenellis, J. [Department of Otorhinolaryngology, University of Athens Medical School, Athens (Greece)

    1998-03-01

    Central nervous system involvement is uncommon in Langerhans cell histiocytosis. The suprasellar region is more frequently affected. There have been few reports of involvement of the brain parenchyma shown on CT or MRI. We present a case of involvement of the pons, showing marked contrast enhancement on MRI. (orig.) With 2 figs., 17 refs.

  14. Langerhans cell histiocytosis with involvement of the pons: case report

    International Nuclear Information System (INIS)

    Vourtsi, A.; Papadopoulos, A.; Moulopoulos, L.A.; Vlahos, L.; Xenellis, J.

    1998-01-01

    Central nervous system involvement is uncommon in Langerhans cell histiocytosis. The suprasellar region is more frequently affected. There have been few reports of involvement of the brain parenchyma shown on CT or MRI. We present a case of involvement of the pons, showing marked contrast enhancement on MRI. (orig.)

  15. Acute leukemia in association with Langerhans cell histiocytosis

    NARCIS (Netherlands)

    R.M. Egeler (Maarten); J.P. Neglia (J.); M. Aricò (Maurizio); B.E. Favara (B.); A. Heitger (A.); M.E. Nesbit (M.)

    1994-01-01

    textabstractLangerhans cell histiocytosis (LCH) and malignancy occurring in the same individual is unusual and has generally been the subject of isolated case reports. To better define the occurrence of these events a registry of cases with synchronous or asynchronous LCH and malignancy was

  16. Sinus Histiocytosis with Massive Lymphadenopathy | Sinclair-Smith ...

    African Journals Online (AJOL)

    Two cases of a recently described entity, 'sinus histiocytosis with massive lymphadenopathy,' occurring in Black males, are reported. Prominent cervical adenopathy was the main presenting feature in both. Histologically, these nodes were characterised by pronounced proliferation of sinus histiocytes which showed ...

  17. The presence of cytokines in Langerhans' cell histiocytosis

    NARCIS (Netherlands)

    deGraaf, JH; Tamminga, RYJ; DamMeiring, A; Kamps, WA; Timens, W

    1996-01-01

    Langerhans' cell histiocytosis (LCH) is characterized by an accumulation and/or proliferation of cells with a Langerhans' cell (LC) phenotype. The aetiology and pathogenesis of LCH are unknown; it is suggested that LCH is caused by an immunological dysregulation. Production of cytokines is a central

  18. Histiocytosis X Involving the Skeletal System in a Black Girl

    African Journals Online (AJOL)

    1974-10-19

    Oct 19, 1974 ... Lieberman et a/.' reported no deaths in a group of 74 patents with unifocal or muitifocal eosinophilic granuloma, but noted consider- able morbidity associated with the multifocal lesions. Our patient has none of the features which severely limit the prognosis in histiocytosis X, and appears to have responded ...

  19. Histiocytosis in a 7 year old boy, a diagnostic dilemma ...

    African Journals Online (AJOL)

    by the infiltration/accumulation of histiocytic cells in affected tissues. Their mode of clinical presentation varies greatly and can represent a diagnostic challenge in our environment where there is a paucity of diagnostic facilities. This report is on a 7 year old boy with probable Histiocytosis who initially presented with signs ...

  20. Somatic activating ARAF mutations in Langerhans cell histiocytosis

    NARCIS (Netherlands)

    Nelson, David S.; Quispel, Willemijn; Badalian-Very, Gayane; van Halteren, Astrid G. S.; van den Bos, Cor; Bovée, Judith V. M. G.; Tian, Sara Y.; van Hummelen, Paul; Ducar, Matthew; MacConaill, Laura E.; Egeler, R. Maarten; Rollins, Barrett J.

    2014-01-01

    The extracellular signal-regulated kinase (ERK) signaling pathway is activated in Langerhans cell histiocytosis (LCH) histiocytes, but only 60% of cases carry somatic activating mutations of BRAF. To identify other genetic causes of ERK pathway activation, we performed whole exome sequencing on

  1. The fascinating world of graph theory

    CERN Document Server

    Benjamin, Arthur; Zhang, Ping

    2015-01-01

    Graph theory goes back several centuries and revolves around the study of graphs-mathematical structures showing relations between objects. With applications in biology, computer science, transportation science, and other areas, graph theory encompasses some of the most beautiful formulas in mathematics-and some of its most famous problems. The Fascinating World of Graph Theory explores the questions and puzzles that have been studied, and often solved, through graph theory. This book looks at graph theory's development and the vibrant individuals responsible for the field's growth. Introducin

  2. Pulmonary histiocytosis X - imaging aspects of pulmonary involvement; Histiocitose X - aspectos radiologicos do acometimento pulmonar

    Energy Technology Data Exchange (ETDEWEB)

    Sabedotti, Ismail Fernando; Maeda, Lucimara; Ferreira, Daniel Miranda; Montandon, Cristiano; Marins, Jose Luiz C. [Universidade Estadual de Campinas, SP (Brazil). Faculdade de Ciencias Medicas. Dept. de Radiologia

    1999-06-01

    Pulmonary histiocytosis X is an idiopathic disease which is and uncommon but important cause of pulmonary fibrosis in young adults. Chest radiographs and high resolution computed tomographic (HRCT) scans of the lungs of 7 patients diagnosed as pulmonary histiocytosis X were examined retrospectively. The authors reviewed the pathologic, clinical and radiographic features of pulmonary histiocytosis X, focusing on differential diagnosis and disease progression. Pulmonary histiocytosis X can be suspected on the basis of chest radiographic findings; predominantly upper lobe nodules and cysts present an increased sensitivity and are virtually pathognomonic of this disorder. Chest HRCT allows good assessment of the evolution of pulmonary histiocytosis X and is also valuable in distinguishing histiocytosis from other disorders that produces nodules or cysts. (author)

  3. Cerebellar and basal ganglion involvement in Langerhans cell histiocytosis

    Energy Technology Data Exchange (ETDEWEB)

    Saatci, I.; Baskan, O.; Haliloglu, M.; Aydingoz, U. [Department of Radiology, Hacettepe University Hospital, Sihhiye 06100, Ankara (Turkey)

    1999-06-01

    Langerhans cell histiocytosis (LCH) is a disease of unknown cause characterised by proliferation of histiocytic granulomas in tissues; the primary cerebral manifestation is diabetes insipidus caused by hypothalamic infiltration. We present a patient in whom, except for the absence of high signal on T 1 weighting in the posterior pituitary, consistent with central diabetes insipidus, MRI showed no evidence of hypothalamic involvement by histiocytosis, despite the long duration of the disease. However, there was bilateral, symmetrical involvement of the cerebellum and globus pallidus in addition to a calvarial lesion. High signal in the cerebellar white matter on T 2-weighted images may represent demyelination, gliosis and cell loss, as previously reported on pathologic examination. (orig.) With 5 figs., 22 refs.

  4. New insights in lymphangioleiomyomatosis and pulmonary Langerhans cell histiocytosis

    Directory of Open Access Journals (Sweden)

    Olga Torre

    2017-09-01

    Full Text Available Lymphangioleiomyomatosis (LAM and pulmonary Langerhans cell histiocytosis (PLCH are rare diseases that lead to progressive cystic destruction of the lungs. Despite their distinctive characteristics, these diseases share several features. Patients affected by LAM or PLCH have similar radiological cystic patterns, a similar age of onset, and the possibility of extrapulmonary involvement. In this review, the recent advances in the understanding of the molecular pathogenesis, as well as the current and most promising biomarkers and therapeutic approaches, are described.

  5. Histiocytosis versus (Hand-Schuller-Christian disease) - a case report

    International Nuclear Information System (INIS)

    Carneiro Filho, Jose Olimar; Leite, Marta Santos; Andrade Neto, Jose Moacyr

    2002-01-01

    The authors report a case of a 4-year-old girl with headache, irritability, othorrea and unilateral exophtalmus. Computed tomography and plain films showed large lytic areas in the vault and base of the skull. No other bones were involved. The diagnosis of histiocytosis X (Hand-Schuller-Christian disease) was confirmed by bone marrow biopsy. This paper presents the cytological and radiological findings of this patient as well as a review of the literature. (author)

  6. Langerhans cell histiocytosis involving central nervous system: a case report

    Energy Technology Data Exchange (ETDEWEB)

    Moon, Won Jin; Park, Dong Woo; Lee, Seung Ro; Hahm, Chang Kok; Ju, Kyung Bin [Hanyang University College of Medicine, Seoul (Korea, Republic of); Kim, Sung Tae [Ulsan University College of Medicine, Seoul (Korea, Republic of)

    1997-01-01

    Langerhans cell histiocytosis(LCH) is a systemic disorder characterized by idiopathic proliferation of histiocytes in the reticuloendothelial system; CNS involvement outside the hypothalamus or pituitary gland is uncommon. We present a case of LCH involving the brainstem, cerebellum, and temporal lobes, and also showing hypothalamic involvement. The lesions were isointense or hypointense on T1WI and hyperintense on T2WI, and showed multifocal enhancing nodules on post-contrast CT and Gd-enhanced MRI.

  7. Need for a cooperative study: Pulmonary Langerhans cell histiocytosis and its management in adults

    NARCIS (Netherlands)

    McClain, Kenneth L.; Gonzalez, Jorge Mario; Jonkers, Rene; de Juli, Emanuela; Egeler, Maarten

    2002-01-01

    BACKGROUND: Pulmonary involvement with Langerhans cell histiocytosis (LCH, formerly known as histiocytosis-X) presents as an interstitial process in children and adults either with or without symptoms. In contrast to other manifestations of LCH, most patients with pulmonary disease are adults.

  8. Fascin overexpression promotes neoplastic progression in oral squamous cell carcinoma

    Directory of Open Access Journals (Sweden)

    Alam Hunain

    2012-01-01

    Full Text Available Abstract Background Fascin is a globular actin cross-linking protein, which plays a major role in forming parallel actin bundles in cell protrusions and is found to be associated with tumor cell invasion and metastasis in various type of cancers including oral squamous cell carcinoma (OSCC. Previously, we have demonstrated that fascin regulates actin polymerization and thereby promotes cell motility in K8-depleted OSCC cells. In the present study we have investigated the role of fascin in tumor progression of OSCC. Methods To understand the role of fascin in OSCC development and/or progression, fascin was overexpressed along with vector control in OSCC derived cells AW13516. The phenotype was studied using wound healing, Boyden chamber, cell adhesion, Hanging drop, soft agar and tumorigenicity assays. Further, fascin expression was examined in human OSCC samples (N = 131 using immunohistochemistry and level of its expression was correlated with clinico-pathological parameters of the patients. Results Fascin overexpression in OSCC derived cells led to significant increase in cell migration, cell invasion and MMP-2 activity. In addition these cells demonstrated increased levels of phosphorylated AKT, ERK1/2 and JNK1/2. Our in vitro results were consistent with correlative studies of fascin expression with the clinico-pathological parameters of the OSCC patients. Fascin expression in OSCC showed statistically significant correlation with increased tumor stage (P = 0.041, increased lymph node metastasis (P = 0.001, less differentiation (P = 0.005, increased recurrence (P = 0.038 and shorter survival (P = 0.004 of the patients. Conclusion In conclusion, our results indicate that fascin promotes tumor progression and activates AKT and MAPK pathways in OSCC-derived cells. Further, our correlative studies of fascin expression in OSCC with clinico-pathological parameters of the patients indicate that fascin may prove to be useful in prognostication and

  9. Fascin overexpression promotes neoplastic progression in oral squamous cell carcinoma

    International Nuclear Information System (INIS)

    Alam, Hunain; Kannanl, Sadhna; Gude, Rajiv; Kane, Shubhada; Dalal, Sorab N; Vaidya, Milind M; Bhate, Amruta V; Gangadaran, Prakash; Sawant, Sharda S; Salot, Shimul; Sehgal, Lalit; Dange, Prerana P; Chaukar, Devendra A; D'cruz, Anil K

    2012-01-01

    Fascin is a globular actin cross-linking protein, which plays a major role in forming parallel actin bundles in cell protrusions and is found to be associated with tumor cell invasion and metastasis in various type of cancers including oral squamous cell carcinoma (OSCC). Previously, we have demonstrated that fascin regulates actin polymerization and thereby promotes cell motility in K8-depleted OSCC cells. In the present study we have investigated the role of fascin in tumor progression of OSCC. To understand the role of fascin in OSCC development and/or progression, fascin was overexpressed along with vector control in OSCC derived cells AW13516. The phenotype was studied using wound healing, Boyden chamber, cell adhesion, Hanging drop, soft agar and tumorigenicity assays. Further, fascin expression was examined in human OSCC samples (N = 131) using immunohistochemistry and level of its expression was correlated with clinico-pathological parameters of the patients. Fascin overexpression in OSCC derived cells led to significant increase in cell migration, cell invasion and MMP-2 activity. In addition these cells demonstrated increased levels of phosphorylated AKT, ERK1/2 and JNK1/2. Our in vitro results were consistent with correlative studies of fascin expression with the clinico-pathological parameters of the OSCC patients. Fascin expression in OSCC showed statistically significant correlation with increased tumor stage (P = 0.041), increased lymph node metastasis (P = 0.001), less differentiation (P = 0.005), increased recurrence (P = 0.038) and shorter survival (P = 0.004) of the patients. In conclusion, our results indicate that fascin promotes tumor progression and activates AKT and MAPK pathways in OSCC-derived cells. Further, our correlative studies of fascin expression in OSCC with clinico-pathological parameters of the patients indicate that fascin may prove to be useful in prognostication and treatment of OSCC

  10. In fascination of fluid mechanics : a symposium in honour of Leen van Wijngaarden

    NARCIS (Netherlands)

    Biesheuvel, A.; Heijst, van G.J.F.

    1998-01-01

    In Fascination of Fluid Dynamics contains a collection of papers by international experts in hydrodynamics, based on oral presentations at a symposium held in honour of Professor Leen van Wijngaarden on his 65th birthday. The book begins with a personal sketch of his life and scientific career. It

  11. Shear bond strength and enamel fracture behavior of ceramic brackets Fascination® and Fascination®2.

    Science.gov (United States)

    Gittner, Robert; Müller-Hartwich, Ralf; Engel, Sylvia; Jost-Brinkmann, Paul-Georg

    2012-01-01

    The purpose of this study was to compare the shear bond strength and incidence of enamel fractures of the ceramic brackets Fascination® and Fascination®2. A total of 360 teeth (180 first upper bicuspids and 180 lower incisors) were stored in 96% ethanol, while 360 other teeth (180 first upper bicuspids and 180 lower incisors) were stored in 0.1% thymol. All 720 teeth were bonded one-half each with Fascination® and Fascination®2 brackets using three different adhesives and three different light curing units. The teeth were debonded with a debonding-device according to DIN EN ISO 10477 using a universal testing machine with a crosshead speed of 1 mm per minute. The enamel surface was then examined stereomicroscopically (10x and 40x magnification). The non-parametric Mann-Whitney U test was used, since the data were not normally distributed. The Fascination®2 brackets provided significantly lower shear bond strength than Fascination® brackets (p = 0.003). Fascination® brackets demonstrated significantly fewer, smaller enamel fractures than Fascination®2 brackets (p = 0.012). The lower shear bond strength of the Fascination®2 brackets is clinically acceptable, but our study's experimental design did not enable us to prove whether this is clinically associated with a lower risk of enamel fracture.

  12. Fascin 1 is dispensable for developmental and tumour angiogenesis

    Directory of Open Access Journals (Sweden)

    Yafeng Ma

    2013-09-01

    The actin bundling protein fascin 1 is not expressed in adult epithelial tissues, but during development it is transiently expressed in many different cell types, and later in adults it is expressed in a subset of immune cells, nervous tissues, endothelial cells, smooth muscle cells and pericytes. In contrast to the wealth of knowledge about the role of fascin 1 in cancer cell migration and invasion, little is known about the involvement of fascin 1 in angiogenesis. We speculated that as angiogenesis involves migration and invasion of tissues by endothelial cells, fascin 1 might have a role in both normal and tumour angiogenesis. Here, we provide evidence that loss of fascin 1 causes relatively minor reductions to angiogenesis during embryonic, postnatal and cancerous development by examining E12.5 hindbrains, postnatal retinas and B16F0 tumour cell allografts in fascin 1-null mice. We also find that in fascin 1 null tissues, endothelial cells display reduced filopodia formation during sprouting. We thus propose that fascin 1 expression promotes angiogenesis via filopodia formation, but is largely dispensable for both normal and tumour angiogenesis.

  13. Intestinal lymphangiectasia associated with recurrence of histiocytosis X.

    Science.gov (United States)

    Hui, C K

    2011-09-01

    Intestinal lymphangiectasia may occur as a primary congenital disorder or a secondary disorder. Secondary lymphangiectasia could be associated with diseases such as abdominal carcinoma, retroperitoneal fibrosis or chronic pancreatitis. This is the first reported case of intestinal lymphangiectasia associated with recurrent histiocytosis X. This case report illustrates the need for more prospective, well-designed studies to determine the natural history and outcome of intestinal lymphangiectasia in the duodenum. Hopefully, these studies will also help clinicians identify which group of patients with intestinal lymphangiectasia in the duodenum is more likely to have a secondary cause.

  14. From normal to abnormal MR findings within three weeks in a solitary pelvic Langerhans histiocytosis

    International Nuclear Information System (INIS)

    Hung, Po-Cheng; Wang, Huei-Shyong; Jaing, Tang-Her; Huang, Tsung-Jen; Pang, Leou-Chuan

    2003-01-01

    We present a histologically proven case of pelvic Langerhans histiocytosis (eosinophilic granuloma) which showed abnormality on MR imaging 3 weeks after a normal MR examination mimicking an infection. (orig.)

  15. Fascin- and α-Actinin-Bundled Networks Contain Intrinsic Structural Features that Drive Protein Sorting.

    Science.gov (United States)

    Winkelman, Jonathan D; Suarez, Cristian; Hocky, Glen M; Harker, Alyssa J; Morganthaler, Alisha N; Christensen, Jenna R; Voth, Gregory A; Bartles, James R; Kovar, David R

    2016-10-24

    Cells assemble and maintain functionally distinct actin cytoskeleton networks with various actin filament organizations and dynamics through the coordinated action of different sets of actin-binding proteins. The biochemical and functional properties of diverse actin-binding proteins, both alone and in combination, have been increasingly well studied. Conversely, how different sets of actin-binding proteins properly sort to distinct actin filament networks in the first place is not nearly as well understood. Actin-binding protein sorting is critical for the self-organization of diverse dynamic actin cytoskeleton networks within a common cytoplasm. Using in vitro reconstitution techniques including biomimetic assays and single-molecule multi-color total internal reflection fluorescence microscopy, we discovered that sorting of the prominent actin-bundling proteins fascin and α-actinin to distinct networks is an intrinsic behavior, free of complicated cellular signaling cascades. When mixed, fascin and α-actinin mutually exclude each other by promoting their own recruitment and inhibiting recruitment of the other, resulting in the formation of distinct fascin- or α-actinin-bundled domains. Subdiffraction-resolution light microscopy and negative-staining electron microscopy revealed that fascin domains are densely packed, whereas α-actinin domains consist of widely spaced parallel actin filaments. Importantly, other actin-binding proteins such as fimbrin and espin show high specificity between these two bundle types within the same reaction. Here we directly observe that fascin and α-actinin intrinsically segregate to discrete bundled domains that are specifically recognized by other actin-binding proteins. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Unusual location of central nervous system langerhans cell histiocytosis: case report

    International Nuclear Information System (INIS)

    Kim, E. Yup; Lee, Jae Kyu; Kim, Chan Kyo; Lee, Chang Hyun; Kang, Chang Ho; Chung, Phil Wook

    2003-01-01

    Langerhans cell histiocytosis of the central nervous system (CNS) usually involves the hypothalamic-pituitary axis, and T1-weighted MR images normally demonstrate infundibular thickening and/or a mass lesion in the hypothalamus and the absence of a posterior pituitary 'bright spot'. We recently encountered a case of CNS langerhans cell histiocytosis with no posterior pituitary 'bright spot' and with lesions involving the cerebellum and basal ganglia but not the hypothalamic-pituitary axis

  17. [Chaos theory: a fascinating concept for oncologists].

    Science.gov (United States)

    Denis, F; Letellier, C

    2012-05-01

    The oncologist is confronted daily by questions related to the fact that any patient presents a specific evolution for his cancer: he is challenged by very different, unexpected and often unpredictable outcomes, in some of his patients. The mathematical approach used today to describe this evolution has recourse to statistics and probability laws: such an approach does not ultimately apply to one particular patient, but to a given more or less heterogeneous population. This approach therefore poorly characterizes the dynamics of this disease and does not allow to state whether a patient is cured, to predict if he will relapse and when this could occur, and in what form, nor to predict the response to treatment and, in particular, to radiation therapy. Chaos theory, not well known by oncologists, could allow a better understanding of these issues. Developed to investigate complex systems producing behaviours that cannot be predicted due to a great sensitivity to initial conditions, chaos theory is rich of suitable concepts for a new approach of cancer dynamics. This article is three-fold: to provide a brief introduction to chaos theory, to clarify the main connecting points between chaos and carcinogenesis and to point out few promising research perspectives, especially in radiotherapy. Copyright © 2012 Société française de radiothérapie oncologique (SFRO). Published by Elsevier SAS. All rights reserved.

  18. Chaos theory: A fascinating concept for oncologists

    International Nuclear Information System (INIS)

    Denis, F.; Letellier, C.

    2012-01-01

    The oncologist is confronted daily by questions related to the fact that any patient presents a specific evolution for his cancer: he is challenged by very different, unexpected and often unpredictable outcomes, in some of his patients. The mathematical approach used today to describe this evolution has recourse to statistics and probability laws: such an approach does not ultimately apply to one particular patient, but to a given more or less heterogeneous population. This approach therefore poorly characterizes the dynamics of this disease and does not allow to state whether a patient is cured, to predict if he will relapse and when this could occur, and in what form, nor to predict the response to treatment and, in particular, to radiation therapy. Chaos theory, not well known by oncologists, could allow a better understanding of these issues. Developed to investigate complex systems producing behaviours that cannot be predicted due to a great sensitivity to initial conditions, chaos theory is rich of suitable concepts for a new approach of cancer dynamics. This article is three-fold: to provide a brief introduction to chaos theory, to clarify the main connecting points between chaos and carcinogenesis and to point out few promising research perspectives, especially in radiotherapy. (authors)

  19. High expression of markers of apoptosis in Langerhans cell histiocytosis

    DEFF Research Database (Denmark)

    Petersen, Bodil Laub; Lundegaard, Pia Rengtved; Bank, M I

    2003-01-01

    53 and the number of cells in apoptosis detected with TUNEL. Langerhans cell histiocytosis cells showed strong expression of p53 and in some cases co-expression of Fas and Fas-L. The expression of Fas-L was significantly higher in infiltrates from patients with single-system disease. The actual...... number of pathological Langerhans cells in apoptosis as estimated by TUNEL was low. CONCLUSIONS: The low number of TUNEL-reactive cells can be explained by the rapid turnover of apoptotic cells in the tissue, not leaving the apoptotic cells long enough in the tissue to be detected. The co......-expression of Fas and Fas-L in some Langerhans cells can lead to an autocrine apoptotic shortcut, mediating the death of the double-positive cells. Our findings suggest that apoptosis mediated through the Fas/Fas-L pathway may contribute to the spontaneous regression of lesions in single-system disease. A delicate...

  20. Disseminated sinus histiocytosis with massive lymphadenopathy: its pathologic aspects.

    Science.gov (United States)

    Buchino, J J; Byrd, R P; Kmetz, D R

    1982-01-01

    Sinus histiocytosis with massive lymphadenopathy (SHML) is generally regarded as a benign, self-limited, pseudolymphomatous process requiring little or no therapy. We studied a 13-year-old black boy with a ten-year clinical course of SHML that had varying, intermittent sites of extranodal involvement, including bone, submandibular gland, trachea, eye, and spinal cord. At the time of death, which was attributed to SHML, additional extranodal sites of involvement included thymus, kidney, heart, liver, and base of brain. Microscopic examination of the SHML lesions at the time of autopsy revealed varying stages of development, from proliferation to involution. This case illustrates that SHML may involve multiple organ systems, can kill, and that histologic evaluation of disease activity at one site cannot be used as an indicator of activity at another.

  1. Langerhans cell histiocytosis revisited: Case report with review

    Directory of Open Access Journals (Sweden)

    Y Pavan Kumar

    2015-01-01

    Full Text Available Langerhans cell histiocytosis (LCH is a group of idiopathic disorders characterized by proliferation of bone marrow derived Langerhans cells and mature eosinophils. Their clinical features simulate common oral findings such as gingival enlargement, oral ulcers, and mobility of teeth, along with nonspecific radiographic features; hence, diagnosing such lesions becomes difficult for the oral physicians. These lesions are commonly seen in childhood; however, we are reporting a case of LCH in 29-year-old adult male. A provisional diagnosis of giant cell granuloma was considered based on history and examination, although the lesion was histologically proven to be LCH and was confirmed with immunohistochemical staining of S100 protein and CD1a antigen. The purpose of this paper is to enhance the understanding of diverse, nonpathognomical oral presentation of LCH that is easily misdiagnosed and overlooked by dentist.

  2. Clinical features and treatment outcomes of Langerhans cell histiocytosis: a nationwide survey from Korea histiocytosis working party.

    Science.gov (United States)

    Kim, Bo Eun; Koh, Kyung-Nam; Suh, Jin Kyung; Im, Ho Joon; Song, Joon Sup; Lee, Ji Won; Kang, Hyoung Jin; Park, Kyung Duck; Shin, Hee Young; Choi, Hyoung Soo; Lee, Soo Hyun; Yoo, Keon Hee; Sung, Ki Woong; Koo, Hong Hoe; Jung, Hye Lim; Chung, Nak-Gyun; Cho, Bin; Kim, Hack Ki; Lyu, Chuhl Joo; Baek, Hee Jo; Kook, Hoon; Park, Jun Eun; Park, Hyeon Jin; Park, Byung-Kiu; Yoo, Eun Sun; Ryu, Kyung Ha; Lee, Kun Soo; Kim, Heung Sik; Lee, Jae Min; Park, Eun Sil; Yoon, Hoi Soo; Lee, Kwang Chul; Lee, Mee Jeong; Lim, Young Tak; Kim, Hwang Min; Park, Sang Kyu; Park, Jeong-A; Kim, Soon Ki; Park, Meerim; Lim, Yeon-Jung; Lee, Young Ho; Seo, Jong Jin

    2014-03-01

    A nationwide survey was conducted to clarify the clinical features and outcomes of Korean children with Langerhans cell histiocytosis (LCH). Korea Histiocytosis Working Party analyzed the data of 603 patients who were diagnosed with LCH between 1986 and 2010 from 28 institutions in Korea. Median age at diagnosis was 65 months (range, 0 to 276 mo). Bone was the most frequently affected organ (79.6%) followed by skin (19.2%). Initially, 419 patients (69.5%) had single-system involvement (SS), 85 (14.1%) with multisystem (MS) disease without risk organ involvement (MS-RO), and 99 (16.4%) multisystem disease with risk organ involvement (MS-RO). The 5-year overall survival (OS) rates in the SS, MS-RO, and MS-RO groups were 99.8%, 98.4%, and 77.0%, respectively (P<0.001), and the 5-year reactivation rates were 17.9%, 33.5%, and 34.3%, respectively (P<0.001). The OS rate was lower in patients with RO involvement (P=0.025) and lack of response to initial treatment (P=0.001). MS involvement (P=0.036) was an independent risk factor for reactivation. Permanent consequences were documented in 99 patients (16.4%). Reactivation of disease, MS involvement, and age at diagnosis ≤ 2 years were associated with higher incidence of permanent consequences. This study emphasized that further efforts are required to improve survival of MS-RO patients and reduce reactivation in younger patients with MS involvement.

  3. Needle aspiration biopsy in the diagnosis of lytic bone lesions in histiocytosis X, Ewing's sarcoma and neuroblastoma

    International Nuclear Information System (INIS)

    Thommesen, P.; Frederiksen, P.; Loewhagen, T.; Willems, J.S.

    1978-01-01

    Cytologic smears obtained by needle aspiration biopsy of lytic bone lesions in 15 patients with histiocytosis X, Ewing's sarcoma and neuroblastoma were reviewed. After conventional staining, histiocytosis X could be diagnosed and differentiated from small cell tumours such as Ewing's sarcoma and neuroblastoma. The need for sampling material for cytochemical and ultrastructural analysis of these small cell tumours by needle aspiration is emphasized. (Auth.)

  4. [Pulmonary Langerhans' cell histiocytosis (PLCH) revealed by pneumothorax: about a case].

    Science.gov (United States)

    Sajiai, Hafsa; Rachidi, Mariam; Serhane, Hind; Aitbatahar, Salma; Amro, Lamyae

    2016-01-01

    Langerhans cell histiocytosis is a rare disease of unknown etiology characterized by the infiltration of Langerhans cells in one or more organs. It has a polymorphic clinical presentation. We report the case of Mr R.Y, age 22, with 8 pack year history of smoking, admitted to hospital with complete spontaneous right-sided pneumothorax. Chest drainage was performed with good evolution. Control chest CT scan showed multiple diffuse cyst formations, predominant in the upper lobes. Lab and imaging tests were performed in order to detect systemic histiocytosis with negative results. Patient's evolution was marked by pneumothorax recurrence; pleurodesis and lung biopsy were performed which confirmed the diagnosis. The diagnosis of Langerhans cell histiocytosis should be evoked in front of pneumothorax associated with lung cystic. The diagnosis is easy in front of a suggestive clinical and radiological picture. Nevertheless, therapeutic options are limited and pneumothorax recurrence is common.

  5. Pituitary and pulmonary abnormalities in an adult patient with Langerhans cell histiocytosis

    International Nuclear Information System (INIS)

    Perez, Adrian; Castro, Ricardo; Pantuso, Silvina

    2003-01-01

    Pulmonary histiocytosis is an uncommon interstitial lung disease, which is infrequent in adults and is part of a spectrum of disorders characterized by monoclonal proliferation and infiltration of organs by Langerhans cells. Histiocytosis X affects only the lungs in more than 85% of the cases. We report a case of a 21-years-old male patient with Diabetes Insipidus (DI) and respiratory symptoms due to a spontaneous pneumothorax with favorable clinical evolution. High-resolution CT demonstrated bilateral nodular and cystic pulmonary lesions. MRI revealed a nodular widening of the pituitary stalk. An endoscopic trans bronchial biopsy was negative for Langerhans cells. After thoracoscopy with surgical biopsy of the lung the diagnosis of Langerhans' cell histiocytosis was confirmed. (author)

  6. Langerhans Cell Histiocytosis: A Diagnostic Challenge in the Oral Cavity

    Directory of Open Access Journals (Sweden)

    Mehmet Ali Altay

    2017-01-01

    Full Text Available Background. Langerhans cell histiocytosis (LCH is a rare disorder of the reticuloendothelial system with unknown etiology. This report aims to present a case of LCH with diffuse involvement of the oral cavity and to raise awareness of the distinguishing features of this diagnostically challenging entity. Case Report. A 26-year-old male patient presented with complaints of teeth mobility, intense pain, and difficulty in chewing. Intraoral and radiological examinations revealed generalized gingival hyperplasia and severe teeth mobility with widespread alveolar bone loss. Periodontal therapy was performed with no significant improvement. An incisional biopsy revealed Langerhans cells and positive reaction to S-100 and CD1, and the patient was diagnosed with LCH. The patient underwent systemic chemotherapy with vinca alkaloids and corticosteroids. Regression of gingival lesions, as well as significant decrease in mobility of the remaining teeth and severity of pain, was achieved during 12 months of follow-up. Conclusion. The rarity and variable system involvement of LCH necessitate a multidisciplinary approach be carried out for accurate diagnosis, effective treatment, and an uneventful follow-up. Awareness of oral manifestations of LCH may aid clinicians greatly in reducing morbidity and mortality associated with this debilitating condition.

  7. LANGERHANS CELL HISTIOCYTOSIS OF THE SCAPULA - DIAGNOSIS & TREATMENT OPTIONS

    Directory of Open Access Journals (Sweden)

    ROHIT PANDEY

    Full Text Available ABSTRACT Langerhans cell histiocytosis (LCH is characterised by an abnormal histiocytic accumulation in tissues such as the lung, spleen, bone marrow, skin, central nervous system, liver and lymph nodes, causing focal or systemic effects. No specific clinical & radiographic presentation of LCH is described in literature. This poses a diagnostic dilemma for surgeons. The scapula is the site of 3% of bone tumours, while for LCH it is the least common site. In a 10-year-old boy with isolated lesion of the scapula with no other systemic involvement, and no specific finding in MRI or CT scan of scapula, diagnosis was confirmed on biopsy. Division into single and multi-system disease is paramount in treatment, given that it is a single system disease. The patient improved clinically on follow-up of 2 years. The scapula is one of the rarest site of LCH, and because various lesions mimic each other, a biopsy is always required, with immunohistochemistry for CD68 & S-100. This was only a single system disease, so conservative management was performed, and the patent improved clinically.

  8. Unusual location of central nervous system langerhans cell histiocytosis: case report

    Energy Technology Data Exchange (ETDEWEB)

    Kim, E. Yup; Lee, Jae Kyu; Kim, Chan Kyo; Lee, Chang Hyun; Kang, Chang Ho; Chung, Phil Wook [Armed Forces Capital Hospital, Seongnam (Korea, Republic of)

    2003-03-01

    Langerhans cell histiocytosis of the central nervous system (CNS) usually involves the hypothalamic-pituitary axis, and T1-weighted MR images normally demonstrate infundibular thickening and/or a mass lesion in the hypothalamus and the absence of a posterior pituitary 'bright spot'. We recently encountered a case of CNS langerhans cell histiocytosis with no posterior pituitary 'bright spot' and with lesions involving the cerebellum and basal ganglia but not the hypothalamic-pituitary axis.

  9. Langerhans' cell histiocytosis presenting with an intracranial epidural hematoma

    Energy Technology Data Exchange (ETDEWEB)

    Lee, K.-W. [Department of Pediatrics, Loma Linda Children' s Hospital and University Medical Center, Loma Linda, CA (United States); McLeary, M.S. [Div. of Pediatric Radiology, Loma Linda Children' s Hospital and University Medical Center, Loma Linda, CA (United States); Zuppan, C.W. [Dept. of Pathology, Loma Linda Children' s Hospital and University Medical Center, Loma Linda, CA (United States); Won, D.J. [Div. of Pediatric Neurosurgery, Loma Linda University Children' s Hospital, Loma Linda, CA (United States)

    2000-05-01

    An 8-year-old boy developed vomiting and severe headache following minor head trauma. A CT scan of the head demonstrated a lytic lesion of the skull and adjacent epidural hematoma. Surgical evacuation and removal of the skull lesion and hematoma were carried out, and pathologic evaluation resulted in a diagnosis of Langerhans' cell histiocytosis (LCH). Epidural involvement of Langerhans' cell histiocytosis is very rare, and we report the first case of LCH presenting as an intracranial epidural hematoma. (orig.)

  10. New methods for assessing the fascinating nature of nature experiences.

    Science.gov (United States)

    Joye, Yannick; Pals, Roos; Steg, Linda; Evans, Ben Lewis

    2013-01-01

    In recent years, numerous environmental psychology studies have demonstrated that contact with nature as opposed to urban settings can improve an individual's mood, can lead to increased levels of vitality, and can offer an opportunity to recover from stress. According to Attention Restoration Theory (ART) the restorative potential of natural environments is situated in the fact that nature can replenish depleted attentional resources. This replenishment takes place, in part, because nature is deemed to be a source of fascination, with fascination being described as having an "attentional", an "affective" and an "effort" dimension. However, the claim that fascination with nature involves these three dimensions is to a large extent based on intuition or derived from introspection-based measurement methods, such as self-reports. In three studies, we aimed to more objectively assess whether these three dimensions indeed applied to experiences related to natural environments, before any (attentional) depletion has taken place. The instruments that were used were: (a) the affect misattribution procedure (Study 1), (b) the dot probe paradigm (Study 2) and (c) a cognitively effortful task (Study 3). These instrument were respectively aimed at verifying the affective, attentional and effort dimension of fascination. Overall, the results provide objective evidence for the claims made within the ART framework, that natural as opposed to urban settings are affectively positive (cfr., affective dimension) and that people have an attentional bias to natural (rather than urban) environments (cfr., attentional dimension). The results regarding the effort dimension are less straightforward, and suggest that this dimension only becomes important in sufficiently difficult cognitive tasks.

  11. New Methods for Assessing the Fascinating Nature of Nature Experiences

    Science.gov (United States)

    Joye, Yannick; Pals, Roos; Steg, Linda; Evans, Ben Lewis

    2013-01-01

    In recent years, numerous environmental psychology studies have demonstrated that contact with nature as opposed to urban settings can improve an individual’s mood, can lead to increased levels of vitality, and can offer an opportunity to recover from stress. According to Attention Restoration Theory (ART) the restorative potential of natural environments is situated in the fact that nature can replenish depleted attentional resources. This replenishment takes place, in part, because nature is deemed to be a source of fascination, with fascination being described as having an “attentional”, an “affective” and an “effort” dimension. However, the claim that fascination with nature involves these three dimensions is to a large extent based on intuition or derived from introspection-based measurement methods, such as self-reports. In three studies, we aimed to more objectively assess whether these three dimensions indeed applied to experiences related to natural environments, before any (attentional) depletion has taken place. The instruments that were used were: (a) the affect misattribution procedure (Study 1), (b) the dot probe paradigm (Study 2) and (c) a cognitively effortful task (Study 3). These instrument were respectively aimed at verifying the affective, attentional and effort dimension of fascination. Overall, the results provide objective evidence for the claims made within the ART framework, that natural as opposed to urban settings are affectively positive (cfr., affective dimension) and that people have an attentional bias to natural (rather than urban) environments (cfr., attentional dimension). The results regarding the effort dimension are less straightforward, and suggest that this dimension only becomes important in sufficiently difficult cognitive tasks. PMID:23922645

  12. Case report 457: Sinus histiocytosis with massive lymphadenopathy (Rosai-Dorfman disease) presenting as lesion in the sacrum

    Energy Technology Data Exchange (ETDEWEB)

    Unni, K K

    1988-03-01

    A 19-year-old women presented with a lytic lesion in the sacrum, associated with pain. Sinus histiocytosis (Rosai-Dorfman disease) was not diagnosed correctly until a biopsy specimen of an enlarged cervical lymph node showed the changes typical of sinus histiocytosis with massive lymphadenopathy. The disease was persistent in the patient and eventually involved the sternum. The patient improved with steroid therapy. The clinical, radiological and pathological aspects of this entity were discussed. It was stressed that radiologists, orthopedic surgeons and pathologists must be aware that sinus histiocytosis with massive lymphadenopathy may manifest initially as a bone 'tumor'.

  13. Early Diagnosis and Monitoring of Neurodegenerative Langerhans Cell Histiocytosis.

    Directory of Open Access Journals (Sweden)

    Elena Sieni

    Full Text Available Neurodegenerative Langerhans Cell Histiocytosis (ND-LCH is a rare, unpredictable consequence that may devastate the quality of life of patients cured from LCH. We prospectively applied a multidisciplinary diagnostic work-up to early identify and follow-up patients with ND-LCH, with the ultimate goal of better determining the appropriate time for starting therapy.We studied 27 children and young adults with either ND-LCH verified by structural magnetic resonance imaging (MRI (group 1 or specific risk factors for (diabetes insipidus, craniofacial bone lesions, but no evidence of, neurodegenerative MRI changes (group 2. All patients underwent clinical, neurophysiological and MRI studies.Seventeen patients had MRI alterations typical for ND-LCH. Nine showed neurological impairment but only three were symptomatic; 11 had abnormal somatosensory evoked potentials (SEPs, and five had abnormal brainstem auditory evoked potentials (BAEPs. MR spectroscopy (MRS showed reduced cerebellar NAA/Cr ratio in nine patients. SEPs showed sensitivity, specificity, positive predictive value (PPV and negative predictive value (NPV for predicting ND-LCH of 70.6% (95%CI, 44.0%-89.7%, 100% (69.2%-100%, 100% (73.5%-100%, and 66.7% (38.4%-88.2%, respectively. Repeated investigations in group 1 revealed increasingly abnormal EP parameters, or neurological examination, or both, in nine of fifteen patients while MRI remained unchanged in all but one patient.A targeted MRI study should be performed in all patients with risk factors for ND-LCH for early identification of demyelination. The combined use of SEPs and careful neurological evaluation may represent a valuable, low-cost, well-tolerated and easily available methodology to monitor patients from pre-symptomatic to symptomatic stages. We suggest a multidisciplinary protocol including clinical, MRS, and neurophysiological investigations to identify a population target for future therapeutic trials.

  14. BISPHOSPHONATES IN LANGERHANS CELL HISTIOCYTOSIS: AN INTERNATIONAL RETROSPECTIVE CASE SERIES

    Directory of Open Access Journals (Sweden)

    Deepak Chellapandian

    2016-07-01

    Full Text Available Background: Bone is the most common organ of involvement in patients with Langerhans cell histiocytosis (LCH, which is often painful and associated with significant morbidity from pathological fractures. Current first-line treatments include chemotherapy and steroids that are effective but often associated with adverse effects, whereas the disease may reactivate despite an initial response to first-line agents. Bisphosphonates are osteoclast inhibitors that have shown to be helpful in treating bone lesions of LCH. To date, there are no large international studies to describe their role in treating bone lesions of LCH. Method: We conducted a multicenter retrospective review of 13 patients with histologically proven LCH, who had received bisphosphonates either at diagnosis or at disease reactivation. Results: Ten patients (77% had a single system bone disease, and 3 (23% had bone lesions as part of multisystem disease. Median follow-up time post-bisphosphonate therapy was 4.6 years (range, 0.8 to 8.2 years. Treatment with bisphosphonates was associated with significant pain relief in almost all patients. Twelve  (92% achieved resolution of active bone lesions, and 10 out of them had no active disease for a median of 3.5 years (range, 0.8 to 5 years. One patient did not respond. No major adverse effects were reported in this series.  Conclusion: Bisphosphonates are well-tolerated drugs that can significantly improve bone pain and induce remission in active bone LCH. Future prospective studies evaluating the role of bisphosphonates in LCH are warranted.

  15. Persistent pulmonary interstitial emphysema in a case of Langerhans cell histiocytosis

    International Nuclear Information System (INIS)

    Abbey, Pooja; Narula, Mahender K.; Anand, Rama; Chandra, Jagdish

    2014-01-01

    We present the case of a 10-month-old boy with multisystem Langerhans cell histiocytosis showing thin-walled lung cysts along with computed tomography (CT) evidence of persistent pulmonary interstitial emphysema (PPIE), in the absence of pneumothorax or pneumomediastinum. Follow-up CT performed after 6 months demonstrated complete resolution of interstitial emphysema

  16. LANGERHANS CELL HISTIOCYTOSIS - EXPRESSION OF LEUKOCYTE CELLULAR ADHESION MOLECULES SUGGESTS ABNORMAL HOMING AND DIFFERENTIATION

    NARCIS (Netherlands)

    DEGRAAF, JH; TAMMINGA, RYJ; KAMPS, WA; TIMENS, W

    Langerhans' cell histiocytosis (LCH) is characterized by an accumulation of cells with a Langerhans' cell (LC) phenotype. Most patients present with solitary skin or bone lesions, but multi-organ lesions may appear Twenty-two LCH-tissue sections from 13 children and adolescents, with lesions at

  17. EXPRESSION OF CELLULAR ADHESION MOLECULES IN LANGERHANS CELL HISTIOCYTOSIS AND NORMAL LANGERHANS CELLS

    NARCIS (Netherlands)

    DEGRAAF, JH; TAMMINGA, RYJ; KAMPS, WA; TIMENS, W

    1995-01-01

    Langerhans cell histiocytosis (LCH) is characterized by lesions with an accumulation and/or proliferation of Langerhans cells (LCs). Little is known of the etiology and pathogenesis of LCH. Although the relation between the LCH cell and normal LCs is currently uncertain, the localizations of the LCH

  18. Melanotic paraganglioma arising in the temporal horn following Langerhans cell histiocytosis

    International Nuclear Information System (INIS)

    Yoo, Jeong Hyun; Rivera, Andreana; Naeini, Ramin M.; Yedururi, Sireesha; Megahead, Hatem; Bayindir, Petek; Fuller, Gregory N.; Suh, Jeong Soo; Adesina, Adekunle M.; Hunter, Jill V.

    2008-01-01

    Intracerebral paragangliomas are rare because of the lack of paraganglial cells in the cerebral tissue. We report a rare case of melanotic paraganglioma arising from the temporal horn of the lateral ventricle in a patient with prior Langerhans cell histiocytosis (LCH) treated with chemotherapy and radiation. (orig.)

  19. MAP2K1 and MAP3K1 mutations in langerhans cell histiocytosis

    NARCIS (Netherlands)

    Nelson, David S.; van Halteren, Astrid; Quispel, Willemijn T.; van den Bos, Cor; Bovée, Judith V. M. G.; Patel, Bhumi; Badalian-Very, Gayane; van Hummelen, Paul; Ducar, Matthew; Lin, Ling; MacConaill, Laura E.; Egeler, R. Maarten; Rollins, Barrett J.

    2015-01-01

    Langerhans cell histiocytosis (LCH) is now understood to be a neoplastic disease in which over 50% of cases have somatic activating mutations of BRAF. However, the extracellular signal-related (ERK) pathway is activated in all cases including those with wild type BRAF alleles. Here, we applied a

  20. Role of fascin in the proliferation and invasiveness of esophageal carcinoma cells

    International Nuclear Information System (INIS)

    Xie, J.J.; Xu, L.Y.; Zhang, H.H.; Cai, W.J.; Mai, R.Q.; Xie, Y.M.; Yang, Z.M.; Niu, Y.D.; Shen, Z.Y.; Li, E.M.

    2005-01-01

    Fascin, an actin-bundling protein, induces membrane protrusions and increases cell motility in various transformed cells. The overexpression of fascin in esophageal squamous cell carcinoma (ESCC) has been described only recently, but the roles and mechanism still remained unclear. Here, by using RNA interference (RNAi), we have stably silenced the expression of the fascin in EC109 cells, an ESCC cell line. Down-regulation of fascin resulted in a suppression of cell proliferation and as well as a decrease in cell invasiveness. Furthermore, we revealed that fascin might have functions in regulating tumor growth in vivo. The effect of fascin on cell invasiveness correlated with the activation of matrix metalloproteases such as MMP-2 and MMP-9. We examined that fascin down-expression also led to a decrease of c-erbB-2 and β-catenin at the protein level. These results suggested that fascin might play crucial roles in regulating neoplasm progression of ESCC

  1. The irresistible fascination of medical theories about opposites.

    Science.gov (United States)

    Angeletti, L R; Frati, L

    1989-01-01

    Theurgical medicine was a part of the eternal fight between good and evil and health was reconciliation with the gods. This duality characterized ancient medicine, i.e. Greek medicine after the Homeric age or Chinese traditional medicine. In the passage to medicine of observation due to the School of Cos duel between good and evil becomes substrate of new medicine and the balances between*opposites represented by elements and qualities were the fundaments of the humoralism. Fascination of opposites continues for centuries up to now, both in western and far eastern medicine: yin/yang, antibody/antigen, cAMP/cGMP, oncogene/antioncogene are examples of this attractive theory. Although fundaments of biological and medical observations are the basis of theories of opposites, the trend is to overcome reality and today represents, following idealism in the 19th century, an inconscious ancestral reminiscence of theurgical philosophy and medicine.

  2. [Sinus histiocytosis (Destombes-Rosai-Dorfman disease) revealed by extranodal spinal involvement].

    Science.gov (United States)

    Bernard, F; Sarran, N; Serre, I; Baldet, P; Callamand, P; Margueritte, G; Astruc, J

    1999-02-01

    Sinus histiocytosis with massive cervical lymphadenopathy (Rosai-Dorfman disease) is a non-neoplastic lymphoproliferative disorder. Extranodal involvement, especially of the nervous system, is unusual. We report a case revealed by neurological symptoms. A 10-year-old girl presented with paraparesis due to a dural extramedullary mass on magnetic resonance imaging. Massive cervical lymphadenopathy appeared secondarily. Radiological investigations showed mediastinal, paranasal sinus and lower eyelid involvement. The diagnosis of Rosai-Dorfman disease was established histologically and by immunohistochemical studies of nodal lesions by the demonstration of characteristic sinus histiocytosis with sheets of S-100 protein and CD-68 positive large histiocytes displaying lymphocyte phagocytosis. A dramatic response occurred with complete resolution of all clinical findings after treatment with corticosteroids and etoposide, although neurological lesions were unchanged on magnetic resonance imaging. Despite its rarity, this case underlines the unknown pathogenesis of this disease (immune dysfunction?) and the difficulties of treatment (choice of chemotherapeutic agents, duration).

  3. Magnetic resonance imaging of thickened pituitary stalk proceeding to langerhans cell histiocytosis in a child

    International Nuclear Information System (INIS)

    Halefoglu, A.M.

    2006-01-01

    Magnetic resonance imaging has shown isolated pituitary stalk thickening in certain cases of idiopathic or secondary central diabetes insipidus (Dl) due to infiltrative processes. We present a 4-year-old boy who was initially diagnosed as having central Dl. The MRI showed isolated pituitary stalk thickening with prominent homogeneous contrast enhancement. The remaining findings on MRI were within normal limits. The patient's personal and family history and laboratory and clinical findings were unremarkable; therefore, he was initially diagnosed as having idiopathic Dl. Since central Dl and isolated pituitary stalk thickening may be considered to be the first manifestations of Langerhans cell histiocytosis, we decided to follow up the patient. After 5 months, following the initial diagnosis, on skeletal X-ray survey, the patient did indeed develop multiple lytic skull lesions which, on biopsy, were histologically typical bone lesions of Langerhans cell histiocytosis. Copyright (2006) Blackwell Science Pty Ltd

  4. Concomitant occurrence of sinus histiocytosis with massive lymphadenopathy and nodal marginal zone lymphoma.

    Science.gov (United States)

    Pang, Changlee S; Grier, David D; Beaty, Michael W

    2011-03-01

    Sinus histiocytosis with massive lymphadenopathy (SHML), also known as Rosai-Dorfman disease, is a rare self-limiting disorder of histiocytes with unknown etiology. Sinus histiocytosis with massive lymphadenopathy is most common in children and young adults and is characterized by painless lymphadenopathy. Histologically there is a proliferation of sinus histiocytes with lymphophagocytosis or emperipolesis. On rare occasions, SHML has been associated with lymphoma, usually involving different anatomic sites and developing at different times. We report a case of concomitant SHML and nodal marginal zone lymphoma involving the same lymph node without involvement of other nodal or extranodal sites. The presence of concomitant SHML within the lymph node involved by nodal marginal zone lymphoma may represent the responsiveness of SHML histiocytes to B-cell-derived cytokines in lymphoproliferative disorders. To our knowledge, this is the first description of concomitant occurrence of SHML and nodal marginal zone lymphoma.

  5. Langerhans cell histiocytosis of bone in an adult: A case report

    Directory of Open Access Journals (Sweden)

    Zachary Christopher, MD

    2018-04-01

    Full Text Available Langerhans cell histiocytosis (LCH may clinically manifest in a variety of ways due to its ability to involve nearly every organ system. LCH may present as a single bone lesion, skin rash, or as invasive disseminated disease and occurs typically in the pediatric and adolescent population, affecting both males and females. Independent of its clinical presentation and severity, LCH lesions share the common histology of CD1a+/CD207+ dendritic cells along with an inflammatory infiltrate, and, based upon improved scientific understanding, is now classified as a myeloproliferative neoplasm. We present a case report of an adult diagnosed with LCH of the pelvis. Keywords: Langerhans cell histiocytosis, Adults, Pelvis

  6. Intracranial non-Langerhans cell histiocytosis presenting as an isolated intraparenchymal lesion

    Energy Technology Data Exchange (ETDEWEB)

    Rajaram, Smitha; Shackley, Fiona; Raghavan, Ashok [Western Bank, Sheffield Children' s Hospital, Sheffield (United Kingdom); Wharton, Stephen B. [University of Sheffield, Department of Neurosciences, Sheffield (United Kingdom); Connolly, Daniel J.A. [Western Bank, Sheffield Children' s Hospital, Sheffield (United Kingdom); University of Sheffield, Academic Radiology, Sheffield (United Kingdom)

    2010-12-15

    Non-Langerhans cell histiocytosis in the absence of cutaneous or other organ involvement is very rare. A Caucasian boy age 3 years 11 months presented with episodes of recurrent right-side seizures over 2 weeks. Brain CT and MR imaging showed a single enhancing left frontal lobe lesion. Stereotactic biopsy was performed and histological examination showed diffuse infiltrate of macrophages with foamy cytoplasm. Four months later there was recurrence of seizure activity despite anti-epileptic medication and a repeat MR scan showed a persistent enhancing lesion in the left frontal lobe. Histological examination of the resection specimen resembled juvenile xanthogranuloma (JXG) involving the central nervous system. In the absence of skin lesions a diagnosis of non-Langerhans cell histiocytosis was made. The child made a full recovery following surgery with resolution of his symptoms. (orig.)

  7. Primary cerebral non-Langerhans cell histiocytosis: MRI and differential diagnosis

    Energy Technology Data Exchange (ETDEWEB)

    Ernemann, U.; Skalej, M.; Voigt, K. [Department of Neuroradiology, University Hospital Tuebingen, Hoppe-Seyler-Strasse 3, 72076 Tuebingen (Germany); Hermisson, M.; Platten, M. [Department of Neurology, University Hospital Tuebingen, Hoppe-Seyler-Strasse 3, 72076 Tuebingen (Germany); Jaffe, R. [Pathology Department, Children' s Hospital of Pittsburgh, 3705 Fifth Avenue, Pittsburgh, PA 15213 (United States)

    2002-09-01

    We report a young woman with primary cerebral non-Langerhans cell histiocytosis of the juvenile xanthogranuloma family. The clinical course was complicated by extensive infiltration of cranial nerves and meninges and epi- and intramedullary spinal dissemination. Whereas the cutaneous form of juvenile xanthogranuloma is usually benign and self-limited, central nervous system involvement is associated with high morbidity and mortality and might therefore be considered a separate clinical entity. (orig.)

  8. Skull Base Langerhans Cell Histiocytosis with Diabetes Insipidus and Panhypopituitarism- A Rare Clinical Entity

    Directory of Open Access Journals (Sweden)

    Anirban Ghosh

    2017-12-01

    Case Report A 16 year old male presented with diminished vision, bilateral ptosis, left sided lateral rectus palsy, hypoesthesia of trigeminal nerve with nasal obstruction for last 5 months. There was polypoidal, bleeding mass in both nasal cavities. Contrast enhanced CT Scan showed a large homogenous mass arising from sphenoid extending into cavernous sinus and the suprasellar region. Endoscopic nasal biopsy revealed abundant Langerhans cell histiocytes, macrophages, neutrophils. Chemotherapy and radiotherapy were administered. But within 2 months the patient presented with Cushingoid features and further diminution of vision. Detailed work-up revealed Hypogonadotrophic hypogonadism and diabetes insipidus. Debulking of the tumour was done and left optic nerve decompression was done. PET scan was performed and showed large, well defined mass with increased FDG uptake in the skull base with suprasellar extension, reaching upto petrous temporal bone and causing bony erosion of ethmoid and sphenoid sinuses. Patient was then advised adjuvant chemotherapy.   Discussion Langerhans cell histiocytosis is a rare group of disorders characterised by abnormal clonal proliferation and accumulation of abnormal dendritic cells. Involvement of base of skull is even rarer. Though diabetes insipidus has been reported in Langerhans cell histiocytosis involving pituitary, panhypopituitarism is rare. These combinations of extensive Langerhans cell histiocytosis of base skull with clinical features of Diabetes insipidus and panhypopituitarism makes this case a rare clinical entity.

  9. Fascin expression in cholesteatoma: correlation with destruction of the ossicular chain and extent of disease.

    Science.gov (United States)

    Binnetoglu, A; Sari, M; Baglam, T; Erbarut Seven, I; Yumusakhuylu, A C; Topuz, M F; Batman, C

    2015-08-01

    Fascin is an actin-bundling protein found in cell membrane protrusions and increases cell motility. The expression of fascin in epithelial neoplasms has been described only recently. No data are available concerning the role of this protein in invasive cholesteatoma. Thus, we investigated the expression of fascin in cholesteatoma tissue and the relationship between fascin expression and intraoperative evaluation of the destruction of the ossicular chain and extent of disease. Cholesteatoma specimens of 28 patients and external auditory canal (EAC) skin specimens of the same patients (as the control group) were collected from mastoidectomies. Immunohistochemical technique was used to investigate the fascin expression in all cholesteatoma tissues and EAC skin specimens. Immunohistochemical staining was assessed semiquantitatively based on the thickness of epithelium. SPSS software version 16.0 (SPSS Inc., Chicago, IL, USA) was performed to statistically analyse the relationships between fascin expression and intraoperative evaluation destruction of ossicular chain and extent of the disease. Immunohistochemically, there was no or very low fascin expression observed in normal epithelial cells of EAC skin, while expressed in cholesteatoma tissue. Also, fascin expression in cholesteatoma tissues was significantly correlated with destruction of ossicular chain and extent of the disease. Fascin expression is usually found in cholesteatoma epithelium and is correlated with destruction of the ossicular chain and extent of disease. Considering all of the correlations between the clinical and histopathological findings, 'fascin immunoexpression scoring' may be used for histological grading of cholesteatoma. © 2015 John Wiley & Sons Ltd.

  10. The pituitary gland in patients with Langerhans cell histiocytosis: a clinical and radiological evaluation.

    Science.gov (United States)

    Kurtulmus, Neslihan; Mert, Meral; Tanakol, Refik; Yarman, Sema

    2015-04-01

    Langerhans cell histiocytosis (LCH) is a rare disease in which the most common endocrine manifestation is diabetes insipidus (DI). Data on anterior pituitary function in patients with LCH are limited. Thus, the present study investigated anterior pituitary function in LCH patients with DI via the evaluation of clinical and radiological findings at disease onset and during follow-up. The present study retrospectively evaluated nine patients with LCH (five males and four females). All diagnoses of LCH were made following histological and/or immunophenotypic analyses of tissue biopsies, bronchoalveolar lavage, or cerebrospinal fluid (CSF). Basal and, if necessary, dynamic pituitary function tests were used to assess anterior pituitary function, and magnetic resonance imaging (MRI) scans were used to image the pituitary. The LCH treatment modality was based on organ involvement. The mean age at onset of DI was 27.6 years (range 15-60 years). One patient (11%) exhibited single organ involvement, while eight patients (89%) displayed multisystem organ involvement. On admittance, one patient had hypogonadotropic hypogonadism, one patient exhibited panhypopituitarism [hypogonadotropic hypogonadism, central hypothyroidism, hypocortisolism, and growth hormone (GH) deficiency], and four patients (44%) displayed hyperprolactinemia. The MRI data revealed infundibular enlargement in seven patients (78%), a thalamic mass in one patient (11%), and the absence of the bright spot in all patients. A single patient (11%) showed a mass in the pons that had a partially empty sella. The patients were treated with radiation therapy (RT), chemotherapy (CT), or a combination of both (RT+CT) and were followed up for a median of 91.8 months (range 2-318 months). Seven patients were assessed during the follow-up period, of whom four patients (57.1%) developed anterior pituitary hormone deficiency, three (43%) were diagnosed with GH deficiency, and one (14%) exhibited gonadotropin deficiency

  11. Investigating the effects of green marketing on development of brand fascination

    Directory of Open Access Journals (Sweden)

    Hamed Abbasi

    2014-04-01

    Full Text Available This paper investigates the effects of different green marketing on brand fascination for a south Korean electronic producer, Samsung. The proposed study designs two questionnaires, one for measuring the effects of green marketing and the other for brand fascination in Likert scale. Cronbach alphas for green marketing and brand fascination are calculated as 0.72 and 0.79, respectively. The study has been implemented among 385 regular customers of Samsung’s electronic devices. Using Spearman correlation ratio as well as stepwise regression analysis, the study has concluded that two components of green marketing including green product and green promotion influence positively on brand fascination, positively.

  12. Immunohistochemical expression of Fascin-1 in colorectal cancer in relation to clinical and pathological parameters.

    Science.gov (United States)

    Piskor, Barbara M; Pryczynicz, Anna; Lubowicka, Emilia; Miniewska, Katarzyna; Zinczuk, Justyna; Zareba, Konrad; Guzinska-Ustymowicz, Katarzyna

    2018-06-11

    Fascins are a group of proteins taking part in the maintenance of a proper structure of the cellular cytoskeleton. Fascin-1 is an actin-bundling protein present in neurons, fibroblasts, endothelial, smooth muscle, dendritic and mesenchymal cells whereas lack of its expression is characteristic of epithelial cells. Fascin-1 overexpression can be observed in neoplastic cells. Therefore, the aim of this study was to assess the expression of Fascin-1 protein in patients with colorectal cancer (CRC) and to analyze associations between Fascin-1 expression and clinical-pathological parameters. The study material included postoperative samples (tumor and unchanged colon tissue) obtained from 51 CRC patients. Fascin-1 expression was assessed in the paraffin sections by immunohistochemistry. A statistically significant correlation was found between the histological type of cancer and the expression of Fascin-1 (p = 0.012). Increased expression of Fascin-1 in CRC was more frequent in adenocarcinoma type without the mucosal component with a better prognosis and decreased expression of this protein correlated with infiltration of cancer cells to blood and lymphatic vessels (p = 0.038). Our findings indicate a potential role of Fascin-1 in the pathogenesis of colon cancer; however, further studies will show whether this protein plays a role in the infiltration of colorectal cancer cells.

  13. Immunohistochemical Analysis of Oral Dysplasia: Diagnostic Assessment by Fascin and Podoplanin Expression

    International Nuclear Information System (INIS)

    Shimamura, Yumiko; Abe, Takahiro; Nakahira, Mitsuhiko; Yoda, Tetsuya; Murata, Shin-ichi; Sugasawa, Masashi

    2011-01-01

    The aim of this study was to investigate fascin and podoplanin expression in oral dysplasia and carcinoma in situ (CIS) immunohistochemically, and to evaluate their relationship to histopathological diagnosis based on architectural and cytological features. Fascin and podoplanin expression patterns were analyzed immunohistologically in 26 specimens of oral lesions, including benign disease (hyperplasia, papilloma, and others), intraepithelial neoplasia/borderline disease (dysplasia), and malignant disease (CIS, invasive squamous cell carcinoma). Fascin expression was scored into four original categories, and podoplanin expression was scored into five previously established categories. The relationship between the immunohistochemically determined scores of fascin and podoplanin expression and the architectural and cytological features in the hematoxylin-eosin-stained slides was analyzed statistically. The immunostaining scores for fascin and podoplanin were significantly higher in dysplasia and CIS than in benign disease (p=0.0011, p=0.00036), and they were significantly higher in dysplasia than in benign disease (p=0.0087, p=0.0032). In all cases of invasive SCC, fascin was expressed mainly in the cytoplasm of the tumor cells and fascin expression extended from the destruction of the basal layer of the epithelium to the upper layer of the epithelium and podoplanin was expressed in the cytoplasm and membrane of the tumor cells. This was the first report of up-regulation of fascin in oral dysplasia. Our results suggest that it would be helpful for improving the diagnostic accuracy of oral dysplasia and CIS to assess the expression of fascin and podoplanin immunohistochemically

  14. Myth polar light. Why sky bands, herring lightnings, and solar winds fascinate; Mythos Polarlicht. Warum Himmelsbaender, Heringsblitze und Sonnenwinde faszinieren

    Energy Technology Data Exchange (ETDEWEB)

    Hunnekuhl, Michael

    2014-07-01

    The actual state of knowledge of the polar-light research is in this illustrated volume as entertainingly as scientific-foundedly presented. The pecularities of pola lights beyond the polar-light zones as for instance in Germany are thematized and the conditions and periods, in which it there occurs, explained. Michael Hunnekuhl succeeds to mediate the fascination and emotion and simultaneously to explain the phenomena according to the latest state of science generally understandably. Which very old interpretations and descriptions are transmitted, which imaginations had men of polar lights long before the science could them explain? Hunnekuhl takes the reader along with into the world of legends and myths around the polar light. An experience report from the deeply snowed up wideness of Lapland lets everybody closely participate at a polar-light observation and feel the emotion, which it can fan. Above 70 polar-light pictures of high value and further explaining graphics show the continuously changing play of colors, supplement the explanations, and make the fascination comprehensible. Spectacular polar-light films from the international space station ISS, photographs from sun-observation satellites, as well as a polar-light film in real time are bound in the book via QR codes and make the time dimension and the dynamics of this fascinating natural spectacle alively comprehensible.

  15. VLBI: A Fascinating Technique for Geodesy and Astrometry

    Science.gov (United States)

    Schuh, H.; Behrend, Dirk

    2012-01-01

    Since the 1970s Very Long Baseline Interferometry (VLBI) has proven to be a primary space-geodetic technique by determining precise coordinates on the Earth, by monitoring the variable Earth rotation and orientation with highest precision, and by deriving many other parameters of the Earth system. VLBI provides an important linkage to astronomy through, for instance, the determination of very precise coordinates of extragalactic radio sources. Additionally, it contributes to determining parameters of relativistic and cosmological models. After a short review of the history of geodetic VLBI and a summary of recent results, this paper describes future perspectives of this fascinating technique. The International VLBI Service for Geodesy and Astrometry (IVS), as a service of the International Association of Geodesy (IAG) and the International Astronomical Union (IAU), is well on its way to fully defining a next generation VLBI system, called VLBI2010. The goals of the new system are to achieve on scales up to the size of the Earth an accuracy of 1 mm in position and of 0.1 mm/year in velocity. Continuous observations shall be carried out 24 h per day 7 days per week in the future with initial results to be delivered within 24 h after taking the data. Special sessions, e.g. for monitoring the Earth rotation parameters, will provide the results in near real-time. These goals require a completely new technical and conceptual design of VLBI measurements. Based on extensive simulation studies, strategies have been developed by the IVS to significantly improve its product accuracy through the use of a network of small (approx 12 m) fast-slewing antennas. A new method for generating high precision delay measurements as well as improved methods for handling biases related to radio source structure, system electronics, and deformations of the antenna structures has been developed. Furthermore, as of January 2012, the construction of ten new VLBI2010 sites has been funded, with

  16. Button sequestrum in a case of localized Langerhans' cell histiocytosis of the ilium: case report

    International Nuclear Information System (INIS)

    Tordeur, M.; Wybier, M.; Laporte, J.L.; Grenier, P.; Laredo, J.D.

    2000-01-01

    Langerhans' cell histiocytosis (LCH) is characterized by a proliferation of cells exhibiting the same immunohistochemical and ultra-structural characteristics as Langerhans' cells of the epidermis. Eosinophilic granuloma, chronic polyostotic disease (Hand-Schuller-Christian disease) and multisystemic disease (Letterer-Siwe disease) all belong to the spectrum LCH. Osseous lesions are the most common findings. the radiological appearance of skeletal LCH depends on the site and on disease activity. Button sequestrum has been described as uncommon in LCH of the skull and exceedingly rare in LCH at other sites. We report a case of localized LCH of the ilium with a button sequestrum. (author)

  17. Monostotic Langerhans' cell histiocytosis in a child with central diabetes insipidus.

    Science.gov (United States)

    Soares, Eduardo Costa Studart; Quidute, Ana Rosa Pinto; Costa, Fábio Wildson Gurgel; Gurgel, Maria Helane Costa; Alves, Ana Paula Negreiros Nunes; Fonteles, Cristiane Sá Roriz

    2012-01-01

    Langerhans'cell histiocytosis (LCH) comprises a rare group of reticuloendothelial system disorders that can produce focal or systemic manifestations. Diabetes insipidus is considered to be an important indicator of serious underlying diseases in children, including LCH. We report the case of a young patient with monostotic LCH confined to the mandibular ramus, who was diagnosed with the disease after presenting symptoms of central diabetes insipidus and was satisfactorily treated with multi-agent chemotherapy. Additionally, we discuss the clinical, radiographic, histological and immunohistochemical findings, as well as the multidisciplinary approach of this important disease, which should receive attention by dental practitioners, especially when it occurs in children.

  18. Splenomegaly unresponsive to standard and salvage chemotherapy in Langerhans cell histiocytosis: a case of extramedullary hematopoiesis.

    Science.gov (United States)

    Christiansen, Ellen C; Ellwein, Marcine; Neglia, Joseph P

    2012-06-01

    Langerhans cell histiocytosis (LCH) is a proliferative disorder of dendritic cells which has evaded efforts to clearly define pathogenesis, diagnostic criteria, and therapeutic response markers. Strides have been made at classification with the recent development of a quantified score of disease severity. Splenic involvement is an indicator of poor prognosis, with spleen size its surrogate marker in evaluation and scoring. We describe a case of pediatric LCH with progressive splenomegaly despite treatment, which when examined at splenectomy revealed no LCH involvement but extramedullary hematopoiesis. These findings thus challenge our understanding of splenomegaly as a marker of disease. Copyright © 2011 Wiley Periodicals, Inc.

  19. Sinus histiocytosis with massive lymphadenopathy (Rosai-Dorfman disease): two case reports.

    Science.gov (United States)

    El Kohen, A; Planquart, X; Al Hamany, Z; Bienvenu, L; Kzadri, M; Herman, D

    2001-12-01

    Sinus histiocytosis with massive lymphadenopathy or Destombes-Rosai-Dorfman's syndrome is a rare benign disease of unknown etiology, usually seen in younger patients. The cases reported concerned a 15-month old Caucasian boy and an 8 year old black boy with unilateral cervical enlargement, occasional fever and without any extranodal involvement. Diagnosis was performed by superficial lymph node biopsy. No immunodeficiency was found. The patients received no therapy and a complete spontaneous resolution was seen after a few months in the two cases. The clinical presentation, histologic characteristics, pathogenesis and treatment of the Destombes-Rosai-Dorfman's syndrome are discussed.

  20. The rapid evolution of CT findings in pulmonary langerhans cell histiocytosis: a case report

    International Nuclear Information System (INIS)

    Kang, Tae Wook; Lee, Kyung Soo; Cho, Eun Yoon

    2007-01-01

    Imaging findings of pulmonary Langerhans cell histiocytosis (PLCH) demonstrate evolving changes over time, and the radiological transitions shown by imaging tools may allow a prediction of histopathological activity in PLCH. However, there are no reports describing how rapidly CT findings change with time. We describe a case of PLCH that showed a rapid evolutional change of the pulmonary lesions in a 48-year-old man, in which the nodular lesions showed cystic changes within two-month follow-up periods on chest CT scans

  1. BRAF V600E-Positive Multisite Langerhans Cell Histiocytosis in a Preterm Neonate

    Directory of Open Access Journals (Sweden)

    Sara V. Bates

    2013-10-01

    Full Text Available Hemorrhagic pustules with a “blueberry muffin” appearance accompanied by respiratory failure in a neonate present a challenging differential diagnosis that includes infections and neoplasms. We present a case of multiorgan, multisite Langerhans cell histiocytosis (LCH, positive for the oncogenic BRAF V600E mutation, in a preterm neonate. Infants with LCH pose a diagnostic challenge due to their heterogeneous presentations. This case is unusual in that the newborn presented with severe multiorgan involvement. Due to the rare incidence, wide spectrum of clinical manifestations, and high mortality rate, clinicians must maintain a high index of suspicion for LCH.

  2. Ouida: the Fascination of Moral Laxity Ouida : fascination pour un relâchement de la morale

    Directory of Open Access Journals (Sweden)

    Franco Marucci

    2009-05-01

    Full Text Available Ouida (pseudonyme de Marie Louise de la Ramée, 1839-1908 quitta Bury St. Edmunds pour Londres en 1857, où l’influence de William Ainsworth, alors rédacteur en chef de Bentley’s Miscellany, lui valut une réputation de romancière. Installée à Florence dès les années 1870, elle y composa d’excellents romans, trépidants et romantiques, sur la haute société, essentiellement à la demande de l’éditeur allemand Tauchnitz, et brossa, dans d’autres, des portraits attendris de la vie paysanne de la Toscane et de la Maremme. Elle finit sa vie dans la pauvreté et mourut à Viareggio. Prolifique et multiforme, son œuvre comprend poésies, pièces de théâtre, livres pour enfants et récits de voyages, ainsi que des essais sur l’esthétique, la politique et la sociologie. Quoiqu’admirée de son vivant par Edward Bulwer Lytton et John Ruskin, sa réputation reste celle d’un écrivain mineur. Profitant du centenaire de sa mort, cet article se propose de redonner à Ouida sa juste place dans la littérature. Il y est question de son thème de prédilection – une fascination ambiguë pour la haute société aux mœurs relâchées, telle qu’on le retrouve dans les romans dits de sa « période majeure », Under Two Flags, Moths, Puck – et, de manière plus fouillée, dans Bertie Cecil, personnage hanté par une étrange et mystérieuse apathie, un fatalisme et une volonté d’anéantissement identitaire.

  3. Langerhans-cell histiocytosis of the cervical spine in an adult patient: Case report and review of the literature.

    Science.gov (United States)

    Vielgut, Ines; Liegl-Atzwanger, Bernadette; Bratschitsch, Gerhard; Leithner, Andreas; Radl, Roman

    2017-06-01

    Langerhans-cell histiocytosis (LCH) is a rare, benign bone tumor, usually occurring in children and younger adults under 20 years old. Only a few cases of solitary bone lesions of the adult spine are reported in literature, therapeutic guidelines or treatment regimens for lesions of the adult spine are not established yet to our knowledge.

  4. Niemann-Pick disease, type B with TRAP-positive storage cells and secondary sea blue histiocytosis

    Directory of Open Access Journals (Sweden)

    R. Saxena

    2009-09-01

    Full Text Available We present 2 cases of Niemann Pick disease, type B with secondary sea-blue histiocytosis. Strikingly, in both cases the Pick cells were positive for tartrate resistant acid phosphatase, a finding hitherto described only in Gaucher cells. This report highlights the importance of this finding as a potential cytochemical diagnostic pitfall in the diagnosis of Niemann Pick disease.

  5. Irradiation of the hypothalamic-hypophyseal area induces complete regression of mucocutaneous lesions in disseminated histiocytosis X

    International Nuclear Information System (INIS)

    Palmieri, G.; Stefani, S.; Gridelli, C.; Conte, A.; Airoma, G.; Contegiacomo, A.; Bianco, A.R.

    1989-01-01

    We report on a 54-year-old woman with disseminated histiocytosis X who had a complete regression of all mucocutaneous lesions within 1 month from the completion of radiation therapy (4500 cGy) to the hypothalamic-hypophyseal (H-H) area. This response lasted 12 months, after which new cutaneous and bone lesions appeared

  6. Health-related quality of life, cognitive functioning and behaviour problems in children with Langerhans cell histiocytosis

    NARCIS (Netherlands)

    Vrijmoet-Wiersma, C. M. Jantien; Kooloos, Vicky M.; Koopman, Hendrik M.; Kolk, Annemarie M.; van der Laan, Ingrid; Grootenhuis, Martha A.; Egeler, R. Maarten

    2009-01-01

    BACKGROUND: This study was designed to evaluate generic and disease-specific health-related quality of life (HRQoL), cognitive functioning and behaviour problems of children with Langerhans Cell Histiocytosis (LCH). Furthermore, we investigated which medical determinants and social demographic

  7. Hepatic involvement of Langerhans cell histiocytosis in children - imaging findings of computed tomography, magnetic resonance imaging and magnetic resonance cholangiopancreatography

    International Nuclear Information System (INIS)

    Shi, Yingyan; Qiao, Zhongwei; Gong, Ying; Yang, Haowei; Li, Guoping; Pa, Mier; Xia, Chunmei

    2014-01-01

    Langerhans cell histiocytosis is a rare disease that occurs mainly in children, and hepatic involvement is generally a poor prognostic factor. To describe CT and MRI findings of hepatic involvement of Langerhans cell histiocytosis in children, especially the abnormal bile duct manifestation on magnetic resonance cholangiopancreatography (MRCP). Thirteen children (seven boys, six girls; mean age 28.9 months) were diagnosed with disseminated Langerhans cell histiocytosis. They underwent CT (n = 5) or MRI (n = 4), or CT and MRI examinations (n = 4) to evaluate the liver involvement. Periportal abnormalities presented as band-like or nodular lesions on CT and MRI in all 13 children. The hepatic parenchymal lesions were found in the peripheral regions of the liver in seven children, including multiple nodules on MRI (n = 6), and cystic-like lesions on CT and MRI (n = 3). In 11 of the 13 children the dilatations of the bile ducts were observed on CT and MRI. Eight of the 13 children underwent MR cholangiopancreatography, which demonstrated stenoses or segmental stenoses with slight dilatation of the central bile ducts, including the common hepatic duct and its first-order branches. The peripheral bile ducts in these children showed segmental dilatations and stenoses. Stenosis of the central bile ducts revealed by MR cholangiopancreatography was the most significant finding of liver involvement in Langerhans cell histiocytosis in children. (orig.)

  8. Hepatic involvement of Langerhans cell histiocytosis in children - imaging findings of computed tomography, magnetic resonance imaging and magnetic resonance cholangiopancreatography

    Energy Technology Data Exchange (ETDEWEB)

    Shi, Yingyan; Qiao, Zhongwei; Gong, Ying; Yang, Haowei; Li, Guoping; Pa, Mier [Children' s Hospital of Fudan University, Department of Radiology, Shanghai (China); Xia, Chunmei [Shanghai Medical College of Fudan University, Physiology and Pathophysiology Department, Shanghai (China)

    2014-06-15

    Langerhans cell histiocytosis is a rare disease that occurs mainly in children, and hepatic involvement is generally a poor prognostic factor. To describe CT and MRI findings of hepatic involvement of Langerhans cell histiocytosis in children, especially the abnormal bile duct manifestation on magnetic resonance cholangiopancreatography (MRCP). Thirteen children (seven boys, six girls; mean age 28.9 months) were diagnosed with disseminated Langerhans cell histiocytosis. They underwent CT (n = 5) or MRI (n = 4), or CT and MRI examinations (n = 4) to evaluate the liver involvement. Periportal abnormalities presented as band-like or nodular lesions on CT and MRI in all 13 children. The hepatic parenchymal lesions were found in the peripheral regions of the liver in seven children, including multiple nodules on MRI (n = 6), and cystic-like lesions on CT and MRI (n = 3). In 11 of the 13 children the dilatations of the bile ducts were observed on CT and MRI. Eight of the 13 children underwent MR cholangiopancreatography, which demonstrated stenoses or segmental stenoses with slight dilatation of the central bile ducts, including the common hepatic duct and its first-order branches. The peripheral bile ducts in these children showed segmental dilatations and stenoses. Stenosis of the central bile ducts revealed by MR cholangiopancreatography was the most significant finding of liver involvement in Langerhans cell histiocytosis in children. (orig.)

  9. Pulmonary Langerhans Cell Histiocytosis with Lytic Bone Involvement in an Adult Smoker: Regression following Smoking Cessation

    Directory of Open Access Journals (Sweden)

    B. Routy

    2015-01-01

    Full Text Available Langerhans cell histiocytosis (LCH is a rare myeloid neoplasm characterized by the proliferation and dissemination of histiocytes. These in turn may cause symptoms ranging from isolated, infiltrative lesions to severe multisystem disease. Pulmonary Langerhans cell histiocytosis (PLCH presents as a localized polyclonal proliferation of Langerhans cells in the lungs causing bilateral cysts and fibrosis. In adults, this rare condition is considered a reactive process associated with cigarette smoking. Recently, clonal proliferation has been reported with the presence of BRAF V600E oncogenic mutation in a subset of PLCH patients. Spontaneous resolution was described; however, based on case series, smoking cessation remains the most effective way to achieve complete remission and prevent long term complications related to tobacco. Herein, we report the case of an adult woman with biopsy-proven PLCH presenting with thoracic (T8 vertebral bone destruction. Both the lung and the bone diseases regressed following smoking cessation, representing a rare case of synchronous disseminated PCLH with bone localization. This observation underscores the contribution of cigarette smoking as a systemic trigger of both pulmonary and extrapulmonary bone lesions. A review of similar cases in the literature is also presented.

  10. High-resolution computed tomography findings in pulmonary Langerhans cell histiocytosis

    Energy Technology Data Exchange (ETDEWEB)

    Rodrigues, Rosana Souza [Universidade Federal do Rio de Janeiro (HUCFF/UFRJ), RJ (Brazil). Hospital Universitario Clementino Fraga Filho. Unit of Radiology; Capone, Domenico; Ferreira Neto, Armando Leao [Universidade do Estado do Rio de Janeiro (UERJ), Rio de Janeiro, RJ (Brazil)

    2011-07-15

    Objective: The present study was aimed at characterizing main lung changes observed in pulmonary Langerhans cell histiocytosis by means of high-resolution computed tomography. Materials and Methods: High-resolution computed tomography findings in eight patients with proven disease diagnosed by open lung biopsy, immunohistochemistry studies and/or extrapulmonary manifestations were retrospectively evaluated. Results: Small rounded, thin-walled cystic lesions were observed in the lung of all the patients. Nodules with predominantly peripheral distribution over the lung parenchyma were observed in 75% of the patients. The lesions were diffusely distributed, predominantly in the upper and middle lung fields in all of the cases, but involvement of costophrenic angles was observed in 25% of the patients. Conclusion: Comparative analysis of high-resolution computed tomography and chest radiography findings demonstrated that thinwalled cysts and small nodules cannot be satisfactorily evaluated by conventional radiography. Because of its capacity to detect and characterize lung cysts and nodules, high-resolution computed tomography increases the probability of diagnosing pulmonary Langerhans cell histiocytosis. (author)

  11. Multisystem Langerhans cell histiocytosis coexisting with metastasizing adenocarcinoma of the lung: A case report

    Directory of Open Access Journals (Sweden)

    Lovrenski Aleksandra

    2013-01-01

    Full Text Available Introduction. Langerhans cell histiocytosis (LCH is an uncommon disease of unknown etiology characterized by uncontrolled proliferation and infiltration of various organs by Langerhans cells. Case report. We presented a 54-year-old man, heavy smoker, with dyspnea, cough, hemoptysis, headache and ataxia, who died shortly after admission to our hospital. On the autopsy, tumor was found in the posterior segment of the right upper pulmonary lobe as well as a right-sided occipitoparietal lesion which penetrated into the right ventricle resulting in internal and external hematocephalus. Histologically and immunohistohemically, the diagnosis of primary lung adenocarcinoma with brain metastasis was made (tumor cells showed positivity for CK7 and TTF-1 which confirmed the diagnosis. In the lung parenchyma around the tumor, as well as in brain tissue around the metastatic adenocarcinoma histiocytic lesions were found. Light microscopic examination of the other organs also showed histiocytic lesions involving the pituitary gland, hypothalamus, spleen and mediastinal lymph nodes. Immunohistochemical studies revealed CD68, S-100 and CD1a immunoreactivity within the histiocytes upon which the diagnosis of Langerhans' cells histiocytosis was made. Conclusion. The multisystem form of LCH with extensive organ involvement was an incidental finding, while metastatic lung adenocarcinoma to the brain that led to hematocephalus was the cause of death.

  12. Radiotherapy for management of Langerhans' cell histiocytosis. Two case reports and a literature review

    International Nuclear Information System (INIS)

    Heyd, R.; Strassmann, G.; Martin, T.; Zamboglou, N.; Donnerstag, F.

    2000-01-01

    The use of radiotherapy in the treatment of Langerhans' cell histiocytosis was first reported in the literature in 1930 and has been proven as effective in numerous studies. We present the results of two female adults with eosinophilic granuloma of bone who underwent conventionally fractionated radiation therapy with total doses of 7x1.8 Gy and 7x2.0 Gy in four different sites. After observation periods raging from three months to six years local control of the disease was achieved in all treated locations. A review of 18 previously published studies include a total of 310 sites of eosinophilic granuloma of bone in 216 patients. It was demonstrated in 13 studies that the patients had complete relief of symptoms. An average of 94.3% had local control of the symptoms. Furthermore, in 12 studies for a total of 344 cases with involvement of other organs local control was reported in an average of 64.8% (range: 14.3-100%). Based on our own observations and on the literature review we conclude that low dose radiation therapy plays an important role in the management of localised Langerhans' cell histiocytosis. In order to minimise the risk of radiation induced neoplasms an accurate and precise radiation technique is required. (orig.) [de

  13. A case report of orbital Langerhans cell histiocytosis presenting as a orbital cellulitis.

    Science.gov (United States)

    Albert-Fort, M; González-Candial, M

    2018-04-08

    A 10-year-old girl was seen with a 3-week history of right upper lid swelling and with no other symptoms or fever. There was no recent history of sinusitis, trauma, or previous infection involving the periorbital area, or response to oral antibiotic treatment. Orbital computed tomography showed a lesion involving the upper margin of the orbit, and bone destruction at the orbital roof. Biopsy performed revealed the presence of Langerhans cell Histiocytosis. The lesion was surgically debulked and corticosteroids were used intra-operatively. The lesion responded to treatment. The orbital involvement of Langerhans cell histiocytosis, despite its low incidence, should be considered in the examination of acute peri-orbital swelling. It usually presents as an osteolytic lesion, and it is confirmed with a histological examination and immunohistochemical techniques for CD1a and S100. An interdisciplinary approach is recommended to rule out multifocal or multisystemic diseases, as well as to develop an appropriate treatment strategy. Copyright © 2018 Sociedad Española de Oftalmología. Publicado por Elsevier España, S.L.U. All rights reserved.

  14. Clinicopathological significance of fascin-1 expression in patients with non-small cell lung cancer

    Directory of Open Access Journals (Sweden)

    Ling XL

    2015-06-01

    Full Text Available Xiao-Ling Ling,* Tao Zhang,* Xiao-Ming Hou, Da Zhao Department of Oncology, The First Hospital of Lanzhou University (The Branch Hospital of Donggang, Lanzhou, Gansu Province, People’s Republic of China *These authors contributed equally to this work Purpose: Fascin-1 promotes the formation of filopodia, lamellipodia, and microspikes of cell membrane after its cross-linking with F-actin, thereby enhancing the cell movement and metastasis and invasion of tumor cells. This study explored the fascin-1 protein’s expression in non-small cell lung cancer (NSCLC tissues and its relationship with clinical pathology and prognostic indicators.Methods: Immunohistochemical analysis was used to determine the expression of fascin-1 in NSCLC tissues. We used quantitative real-time polymerase chain reaction and western blot analysis to further verify the results. The fascin-1 expression and statistical method for clinical pathological parameters are examined by χ2. Kaplan–Meier method is used for survival analysis. Cox’s Proportional Hazard Model was used to conduct a combined-effect analysis for each covariate.Results: In 73 of the 128 cases, NSCLC cancer tissues (57.0% were found with high expression of fascin-1, which was significantly higher than the adjacent tissues (35/128, 27.3%. The results suggested that the high expression of fascin-1 was significantly correlated with lymph node metastasis (P=0.022 and TNM stage (P=0.042. The high fascin-1 expression patients survived shorter than those NSCLC patients with low fascin-1 expression (P<0.05. Univariate analysis revealed that lymph node metastasis, TNM stage, and fascin-1 expression status were correlated with the overall survival. Similarly, lymph node metastasis, TNM stage, and fascin-1 expression status were significantly associated with the overall survival in multivariate analyses by using the Cox regression model.Conclusion: The fascin-1 protein may be a useful prognostic indicator and

  15. Isolated thymic Langerhans cell histiocytosis discovered on F-18 fluorodeoxyglucose positron emission tomography/computed tomography (F-18 FDG PET/CT).

    Science.gov (United States)

    Turpin, Sophie; Carret, Anne-Sophie; Dubois, Josée; Buteau, Chantal; Patey, Natalie

    2015-11-01

    The thymic infiltration in young patients with multisystemic Langerhans cell histiocytosis and its radiologic features are well known. However, isolated thymic disease has seldom been reported in the literature. We report the case of a 10-month-old child admitted for fever of unknown origin. Whole-body F-18 fluorodeoxyglucose positron emission tomography/computed tomography (F-18 FDG PET/CT) was performed to identify a focus of infection. It demonstrated an unusual aspect of the thymus, which led to further investigation and revealed isolated infiltration of the thymus by Langerhans cell histiocytosis. The patient was treated accordingly and is now disease free. As evaluation of Langerhans cell histiocytosis patients with F-18 FDG PET/CT is becoming more frequent, it is important to be aware of the scintigraphical characteristics of thymic Langerhans cell histiocytosis.

  16. Isolated thymic Langerhans cell histiocytosis discovered on F-18 fluorodeoxyglucose positron emission tomography/computed tomography (F-18 FDG PET/CT)

    Energy Technology Data Exchange (ETDEWEB)

    Turpin, Sophie [CHU Sainte-Justine, Nuclear Medicine, Montreal (Canada); Carret, Anne-Sophie [CHU Sainte-Justine, Hemato-Oncology, Montreal (Canada); Dubois, Josee [CHU Sainte-Justine, Radiology, Montreal (Canada); Buteau, Chantal [CHU Sainte-Justine, Infectious Diseases, Montreal (Canada); Patey, Natalie [CHU Sainte-Justine, Pathology, Montreal (Canada)

    2015-11-15

    The thymic infiltration in young patients with multisystemic Langerhans cell histiocytosis and its radiologic features are well known. However, isolated thymic disease has seldom been reported in the literature. We report the case of a 10-month-old child admitted for fever of unknown origin. Whole-body F-18 fluorodeoxyglucose positron emission tomography/computed tomography (F-18 FDG PET/CT) was performed to identify a focus of infection. It demonstrated an unusual aspect of the thymus, which led to further investigation and revealed isolated infiltration of the thymus by Langerhans cell histiocytosis. The patient was treated accordingly and is now disease free. As evaluation of Langerhans cell histiocytosis patients with F-18 FDG PET/CT is becoming more frequent, it is important to be aware of the scintigraphical characteristics of thymic Langerhans cell histiocytosis. (orig.)

  17. Clinicopathologic significance of fascin, extracellular matrix metalloproteinase inducer, and ezrin expressions in colorectal adenocarcinoma

    Directory of Open Access Journals (Sweden)

    Eun-Joo Jung

    2011-01-01

    Full Text Available Background: The over expression of fascin, extracellular matrix metalloproteinase inducer (EMMPRIN, and ezrin proteins has been associated with poor prognosis in various carcinomas and sarcomas. However, very few studies have reported the relationship between the expression of fascin, EMMPRIN, and ezrin proteins and the clinico-pathologic parameters of colorectal carcinomas. Aims: The aim was to investigate the relationship between fascin, EMMPRIN, and ezrin proteins in colorectal adenocarcinomas and their correlation with clinico-pathologic parameters. Settings and Design: The expression of fascin, EMMPRIN, and ezrin proteins was studied in 210 colorectal adenocarcinoma patients through immunohistochemical staining. Materials and Methods: Immunohistochemical staining by the avidin-biotin peroxidase method was done. The scoring of each protein expression was done and divided into three groups (negative, low-, and high-expression groups. Statistical Analysis: A chi-square test, and Kendall′s tau-b correlation test were used for comparing. Survival analysis was performed using the Kaplan-Meier method with log-rank tests and the Cox proportional hazard model. Results: The percentages of the high-expression group of fascin, EMMPRIN, and ezrin proteins in colorectal adenocarcinomas were 24%, 73%, and 62%, respectively. Weak positive correlations were observed among these protein expressions. An increased expression of the fascin protein was significantly associated with advanced tumor depth and shorter survival times, and a high expression of fascin protein was an independent prognostic factor in univariate and multivariate survival analyses. EMMPRIN and ezrin protein expressions were not associated with the clinico-pathologic parameters. Conclusions: The high expression of fascin protein may be an unfavorable prognostic marker for individual colorectal cancer patients.

  18. Aspects of pulmonary histiocytosis X on high resolution computed tomography; Aspectos da histiocitose X pulmonar na tomografia computadorizada de alta resolucao (TCAR)

    Energy Technology Data Exchange (ETDEWEB)

    Costa, N.S.S.; Castro Lessa Angela, M.T. de; Angelo Junior, J.R.L.; Silva, F.M.D.; Kavakama, J.; Carvalho, C.R.R. de; Cerri, G.G. [Sao Paulo Univ., SP (Brazil). Faculdade de Medicina. Hospital das Clinicas. Inst. do Coracao

    1995-01-01

    Pulmonary histiocytosis X is a disease that occurs in young adults and presents with nodules and cysts, mainly in upper lobes, with consequent pulmonary fibrosis. These pulmonary changes are virtually pathognomonic findings on high resolution computed tomography, that allows estimate the area of the lung involved and distinguish histiocytosis X from other disorders that also produces nodules and cysts. (author). 10 refs, 2 tabs, 6 figs.

  19. Fascin and EMMPRIN expression in primary mucinous tumors of ovary: a tissue microarray study.

    Science.gov (United States)

    Alici, Omer; Kefeli, Mehmet; Yildiz, Levent; Baris, Sancar; Karagoz, Filiz; Kandemir, Bedri

    2014-12-01

    The aim of this study was to compare the expressions of fascin and EMMPRIN in primary malignant, borderline and benign mucinous ovarian tumors, and to investigate the relationship of these markers with tumor progression and their applicability to differential diagnosis. An immunohistochemical study was performed for fascin and EMMPRIN using the tissue microarray technique. Eighty-one cases were included in the study; there were 37 benign, 25 borderline and 19 malignant primary mucinous ovarian tumors. For each case, a total staining score was determined, consisting of scores for extent of staining and intensity of staining. The cases were allocated to negative, weakly positive and strongly positive staining categories, according to the total staining score. Both of the markers were significantly negative in benign tumors as compared with borderline and malignant tumors. There was no significant difference between borderline and malignant groups for both markers. Sixty-eight percent of malignant tumors were stained positive by fascin, while this rate was 40% for borderline mucinous tumors. All malignant tumors were strongly stained positive for EMMPRIN, while this rate was 92% for borderline mucinous tumors. The rest of the cases stained weakly positive. No significant difference in staining score was found between fascin and EMMPRIN expression. In ovarian primary mucinous tumors, fascin and EMMPRIN may play an important role in tumor progression from benign tumor to carcinoma. In that context, EMMPRIN and fascin expression may have potential application in the differential diagnosis of some diagnostically problematic mucinous ovarian tumors. However, the differential diagnostic applicability of EMMPRIN appears to be more limited than that of fascin due to its wide spectrum of staining in mucinous ovarian tumors. Copyright © 2014 Elsevier GmbH. All rights reserved.

  20. [Neuroimaging of Langerhans cell histiocytosis in the central nervous system of children].

    Science.gov (United States)

    De La Hoz Polo, M; Rebollo Polo, M; Fons Estupiña, C; Muchart López, J; Cruz Martinez, O

    2015-01-01

    Langerhans cell histiocytosis (LCH) is a rare disease characterized by the accumulation within tissues of anomalous dendritic cells similar to Langerhans cells. The clinical presentation varies, ranging from the appearance of a single bone lesion to multisystemic involvement. Central nervous system (CNS) involvement, manifesting as diabetes insipidus secondary to pituitary involvement, has been known since the original description of the disease. Two types of CNS lesions are currently differentiated. The first, pseudotumoral lesions with infiltration by Langerhans cells, most commonly manifests as pituitary infiltration. The second, described more recently, consists of neurodegenerative lesions of the CNS associated with neurologic deterioration. This second type of lesion constitutes a complication of the disease; however, there is no consensus about the cause of this complication. Our objective was to describe the radiologic manifestations of LCH in the CNS in pediatric patients. Copyright © 2013 SERAM. Published by Elsevier España, S.L.U. All rights reserved.

  1. Perianal Ulcer and Diabetes Insipidus: A Rare Presentation of Langerhans Cell Histiocytosis in an Adult Male

    Directory of Open Access Journals (Sweden)

    Ng Chong Beng

    2017-07-01

    Full Text Available Langerhans cell histiocytosis (LCH, previously known as Histiocystosis X, is a rare idiopathic disease caused by a build-up of langerhan cells in the body. LCH has a heterogenous form of clinical presentation and presents with varying degree of severity. The severity often depends on the disease burden. LCH can manifest as a unifocal disease, multifocal-unisystem or multifocal-multisystem disease with the latter being more fatal than the rest. Risk organ involvement confers a grim prognosis. Perianal lesions are extremely rare skin manifestation of LCH with only few cases reported in the past. Vinca-alkaloids and steroid therapy have been shown to be effective in a large percentage of those presenting with LCH. This case report highlights the diagnosis and management of LCH presenting as a painful perianal ulcer in the background of newly diagnosed diabetes insipidus.

  2. A Rare Case of Erdheim-Chester Disease and Langerhans Cell Histiocytosis Overlap Syndrome

    Directory of Open Access Journals (Sweden)

    Shahzaib Nabi

    2015-01-01

    Full Text Available A 48-year-old woman with a past medical history of seizures and end-stage renal disease secondary to obstructive uropathy from retroperitoneal fibrosis presented to the emergency department with seizures and altered mental status. A Glasgow Coma Scale of 4 prompted intubation, and she was subsequently admitted to the intensive care unit. Magnetic resonance imaging of the brain performed to elucidate the aetiology of her seizure showed a dural-based mass within the left temporoparietal lobe as well as mass lesions within the orbits. Further imaging showed extensive retroperitoneal fibrosis extending to the mediastinum with involvement of aorta and posterior pleural space. Imaging of the long bones showed bilateral sclerosis and cortical thickening of the diaphyses. Imaging of the maxillofacial structures showed osseous destructive lesions involving the mandible. These clinical and radiological features were consistent with a diagnosis of Erdheim-Chester disease; however, the patient’s skin biopsy was consistent with Langerhans cell histiocytosis.

  3. Indeterminate cell histiocytosis in a pediatric patient: successful treatment with thalidomide.

    Science.gov (United States)

    Tóth, Béla; Katona, Mária; Hársing, Judit; Szepesi, Agota; Kárpáti, Sarolta

    2012-04-01

    The 15-year-old male patient presented several 2-6 mm large livid reddish-yellowish, shiny, compact papules on the head, trunk and extremities, which had developed within the last 4 months. Histology showed normal epidermis with dense dermal infiltrate of histiocytes accompanied by few eosinophils, Touton or foamy giant cells. The histiocytes were S100 positive, CD1a negative and did not contain Birbeck granules ultrastructurally. Chest X ray, EEG, skull MRI did not show pathology. Opthalmology, neurology, oto-rhino-laryngology did not reveal alterations. Based upon the clinical symptoms and the histopathology, the diagnosis of indeterminate cell histiocytosis was confirmed. Cryotherapy and cauterization did not stop the progression of the disease, however, under thalidomide treatment no new symptoms developed and the lesions healed with pigmentation.

  4. Polyclonal T-cells express CD1a in Langerhans cell histiocytosis (LCH lesions.

    Directory of Open Access Journals (Sweden)

    Jennifer A West

    Full Text Available Langerhans cell histiocytosis (LCH is a complex and poorly understood disorder that has characteristics of both inflammatory and neoplastic disease. By using eight-colour flow cytometry, we have identified a previously unreported population of CD1a(+/CD3(+ T-cells in LCH lesions. The expression of CD1a is regarded as a hallmark of this disease; however, it has always been presumed that it was only expressed by pathogenic Langerhans cells (LCs. We have now detected CD1a expression by a range of T-cell subsets within all of the LCH lesions that were examined, establishing that CD1a expression in these lesions is no longer restricted to pathogenic LCs. The presence of CD1a(+ T-cells in all of the LCH lesions that we have studied to date warrants further investigation into their biological function to determine whether these cells are important in the pathogenesis of LCH.

  5. Prognostic significance of fascin expression in advanced colorectal cancer: an immunohistochemical study of colorectal adenomas and adenocarcinomas

    International Nuclear Information System (INIS)

    Hashimoto, Yosuke; Skacel, Marek; Lavery, Ian C; Mukherjee, Abir L; Casey, Graham; Adams, Josephine C

    2006-01-01

    Fascin is an actin bundling protein with roles in the formation of cell protrusions and motility of mesenchymal and neuronal cells. Fascin is normally low or absent from epithelia, but is upregulated in several epithelial neoplasms where it may contribute to an invasive phenotype. Here, we report on the prevalence and potential clinical significance of fascin expression in relation to the progression of colorectal adenocarcinoma and to tumor cell proliferation as measured by Ki67 index. Conventional tissue sections of 107 colorectal adenomas and 35 adenocarcinomas were analyzed by immunohistochemistry for fascin and Ki67 expression. Fascin expression and Ki67 proliferation index were also investigated by use of a tissue microarray containing cores from a further 158 colorectal adenocarcinomas and 15 adenomas linked to a CCF, IRB-approved database with a mean of 38 months of clinical follow-up. Survival analysis was carried out by the Kaplan-Meier and Cox regression methods. Fascin was not expressed by the normal colonic epithelium. In conventional sections, 16% of adenomas and 26% of adenocarcinomas showed fascin expression in greater than 10% of the tumor cells. In the clinically-annotated tumors, fascin immunoreactivity was more common in tumors located in the proximal colon (p = 0.009), but was not associated with age, gender, or TNM stage. Patients with stage III/IV adenocarcinomas (n = 62) with strong fascin immunoreactivity had a worse prognosis than patients with low or absent fascin, (3-year overall survival of 11% versus 43% for fascin-negative patients; p = 0.023). In adenomas, fascin and Ki67 tended to be inversely correlated at the cellular level; this trend was less apparent in adenocarcinomas. Fascin is upregulated in a proportion of adenomas, where its expression is often focal. Strong and diffuse expression was seen in a subset of advanced colorectal adenocarcinomas that correlated with shorter survival in stage III and IV patients. Fascin may have

  6. Concomitant sinus histiocytosis with massive lymphadenopathy (Rosai-Dorfman Disease) and diffuse large B-cell lymphoma: A case report

    OpenAIRE

    Moore, JC; Zhao, X; Nelson, EL

    2008-01-01

    Abstract Introduction Sinus histiocytosis with massive lymphadenopathy, also known as Rosai-Dorfman Disease, is a rare and benign source of lymphadenopathy first described in 1969, which mimics neoplastic processes. This disease commonly presents in children and young adults with supra-diaphragmatic lymphadenopathy or extranodal lesions consisting of tissue infiltrates composed of a polyclonal population of histiocytes. Since its description greater than 400 cases have been described, sometim...

  7. Primary Langerhans cell histiocytosis (LCH in the adult cervical spine: A case report and review of the literature

    Directory of Open Access Journals (Sweden)

    Sang-Deok Kim, M.D.

    2017-03-01

    Full Text Available Langerhans cell histiocytosis (LCH of the spine is a common benign disease in children and adolescents that rarely affects adults. Main management of single lesion (unifocal vertebral LCH is conservative method, unless there is neurological deficit due to mass effect, surgery must be considered. This is an interesting and rare case report of the patient with LCH at C5 vertebral body who underwent fusion surgery.

  8. Langerhans Cell Histiocytosis in Childhood: Review, Symptoms in the Oral Cavity, Differential Diagnosis and Report of One Case

    Directory of Open Access Journals (Sweden)

    Mohammad Shooriabi

    2016-08-01

    Full Text Available Background Langerhans cell histiocytosis (LCH is a rare disease in which monoclonal migration and proliferation of specific dendritic cells is seen. The disease primarily affects the bones and skin, but there is a possibility that involves other organs or appears as a multi-systemic disease. Case Report In oral examination of a nine-month girl, two deep wounds with a yellow membrane with approximate size of 1 × 1 cm on both sides of mandibular alveolar ridge were seen. The edges of the wounds were swollen and proliferated and redder than the surrounding mucosa. At the touch the edges of the wound were not indurated. The wound were created from the third-month and the size of wounds had become slightly larger within 6 months. According to the chronic wound and being non-responsive to various systemic and local treatments, incisional biopsy was taken from the wounds. Langerhans cell histiocytosis was confirmedhistologically and immune histochemically. Conclusion Mouth ulcers may be the only symptoms of Langerhans cell histiocytosis. Therefore, the role of dentist could be important in diagnosis of this disease.

  9. The role of bone scintigraphy in Langerhans' cell histiocytosis; a case report; Interet de la scintigraphie osseuse dans l'histiocytose langerhansienne: a propos d'un cas

    Energy Technology Data Exchange (ETDEWEB)

    Razzouk, M.; Carrier, P.; Darcourt, J. [Centre TEP, Hopital de l' Archet-1, Service Universitaire de Medecine Nucleaire, 06 - Nice (France); Razzouk, M.; Carrier, P.; Darcourt, J. [Federation interhospitaliere, CHU, CAL universitaire de Nice, 06 - Nice (France); Deville, A. [Hopital de l' Archet, Service d' Hemato-Oncologie Pediatrique, 06 - Nice (France); Cadet, G. [Centre Hospitalier intercommunal de Grasse, Service de Pediatrie, 06 - Grasse (France)

    2008-09-15

    We present one case of bone-Langerhans cell histiocytosis in a three-year-old male child presenting osseous lesions in the skull and the femur, which are very frequent localizations in histiocytosis. Bone scintigraphy is useful for both initial staging and follow-up associated with other imaging modalities. (authors)

  10. Formens fascination

    DEFF Research Database (Denmark)

    Prebensen, Henrik

    2006-01-01

    Sprogvidenskab, matematisk lingvistik, matematik, humaniora, sprogform, Saussure, Frege, Russel, Reichenbach, Chomsky, formalisme, funktionalisme......Sprogvidenskab, matematisk lingvistik, matematik, humaniora, sprogform, Saussure, Frege, Russel, Reichenbach, Chomsky, formalisme, funktionalisme...

  11. Kubens fascination

    DEFF Research Database (Denmark)

    Skude, Flemming

    2002-01-01

    Anmeldelse af Nykredits domicil på Kalvebod Brygge referende til Ford Foundation i New York og nutidens præference for minimalistisk kubisme.......Anmeldelse af Nykredits domicil på Kalvebod Brygge referende til Ford Foundation i New York og nutidens præference for minimalistisk kubisme....

  12. Greger Anderson & Ursula Geisler: Fruktan, fascination, frändskap [... etc.

    DEFF Research Database (Denmark)

    Fjeldsøe, Michael

    2007-01-01

    review essay: Greger Andersson & Ursula Geisler (eds.), Fruktan, fascination och frändskap. Det svenska musiklivet och nazismen, Malmö, 2006; Henrik Karlsson, Det fruktade märket. Wilhelm Peterson-Berger, antisemitismen och antinazismen, Malmö, 2005; Horst Weber and Stefan Drees (eds.), Quellen z...

  13. A Fascinating Application of Steiner's Theorem for Trapezium: Geometric Constructions Using Straightedge Alone

    Science.gov (United States)

    Stupel, Moshe; Ben-Chaim, David

    2013-01-01

    Based on Steiner's fascinating theorem for trapezium, seven geometrical constructions using straight-edge alone are described. These constructions provide an excellent base for teaching theorems and the properties of geometrical shapes, as well as challenging thought and inspiring deeper insight into the world of geometry. In particular, this…

  14. Langerhans Cell Histiocytosis of the Cranial Base: Is Low-Dose Radiotherapy Effective?

    Directory of Open Access Journals (Sweden)

    Andreas Meyer

    2012-01-01

    Full Text Available Introduction. Langerhans cell histiocytosis (LCH is a rare disease of unknown etiology with different clinical features. A standardised treatment has not been established so far. Case Report. We report a case of a 28-year-old patient who initially presented with hypesthesia of the fifth cranial nerve and pain of the left ear. Diagnosis showed a tumour localised in the cranial base with a maximum diameter of 4.1 cm. The diagnosis of LCH was confirmed histologically by biopsy. Diagnostic workup verified the cranial lesion as the sole manifestation of LCH. A total dose of 9 Gy (single dose 1.8 Gy was delivered. The symptoms dissolved completely within 6 months after radiation; repeated CT and MRI scans revealed a reduction in size of the lesion and a remineralisation of the bone. After a followup of 13 years the patient remains free of symptoms without relapse or any side effects from therapy. Discussion. Due to the indolent course of the disease with a high rate of spontaneous remissions the choice of treatment strongly depends on the individual clinical situation. In the presented case low-dose radiotherapy was sufficient to obtain long-term local control in a region with critical structures and tissues.

  15. An Aggressive Form of Langerhan Cell Histiocytosis in an Adult: Therapeutic Challenges

    Directory of Open Access Journals (Sweden)

    Karan Seegobin

    2017-01-01

    Full Text Available Langerhans cell histiocytosis (LCH is rare in adults. Regular follow-up is mandatory due to reoccurrence. A 35-year-old male with an incidental left iliac bone lesion was diagnosed with LCH. He later became symptomatic with hip pain and spread of the disease. Despite excision of the symptomatic iliac lesion, he had progression while on cytarabine and nivolumab, evidenced by increased bone pain and involvement of other bones on imaging. He underwent excision of the jaw lesion followed by vinblastine; he was pain free and had stable disease on PET imaging after 3 months. LCH is an uncommon neoplasia. Treatment is reserved for symptomatic patients while asymptomatic patients are observed. Follow-up is imperative due to the risk of reoccurrence. Despite surgical treatment together with one of the front-line agents for refractory disease, in this case cytarabine, he still had progression of the disease. Furthermore, the trial of nivolumab was of no benefit. This case highlights good response to vinblastine which is previously reported to have good success. No trials are published, and the optimal strategy has yet to be defined. LCH with multiple bony involvement can be aggressive and therapeutically challenging.

  16. A rare case of langerhans cell histiocytosis of the gastrointestinal tract

    Institute of Scientific and Technical Information of China (English)

    Uday Shankar; Monika Prasad; Om P Chaurasia

    2012-01-01

    Langerhans cell histiocytosis (LCH) is a group of idiopathic disorders characterized by the proliferation of specialized,bone marrow-derived langerhans cells and mature eosinophils.The clinical spectrum ranges from an acute,fulminant,disseminated disease called LettererSiwe disease to solitary or few,indolent and chronic lesions of the bone or other organs called eosinophilic granuloma.Involvement of the gastrointestinal tract is very rare in LCH.We present the case of a 53-year-old woman referred by her primary care physician for a screening colonoscopy.A single sessile polyp,measuring 4 mm in size,was found in the rectum.Histopathological examination revealed that the lesion was relatively well circumscribed and comprised mainly a mixture of polygonal cells with moderate-to-abundant pink slightly granular cytoplasm.The nuclei within these cells had frequent grooves and were occasionally folded.Immunohistochemical staining was positive for CD-1a which confirmed the diagnosis of LCH.On further workup,there was no evidence of involvement of any other organ.On follow up colonoscopy one year later,there was no evidence of disease recurrence.Review of the published literature revealed that LCH presenting as solitary colonic polyp is rare.However,with the increasing rates of screening colonoscopy,more colonic polyps may be identified as LCH on histopathology.This underscores the importance of recognizing this rare condition and ensuring proper follow-up to rule out systemic disease.

  17. Radiologic findings of adult pelvis and appendicular skeletal Langerhans cell histiocytosis in nine patients

    International Nuclear Information System (INIS)

    Song, You Seon; Lee, In Sook; Kim, Do Kyung; Yi, Jae Hyuck; Cho, Kil Ho; Song, Jong Woon

    2011-01-01

    The purpose of this article was to evaluate the radiologic findings of adult pelvis and appendicular skeletal Langerhans cell histiocytosis (LCH), emphasizing the CT and MR findings. The images of nine patients with pathologically proven LCH (five men and four women; mean age, 37.11 years) were retrospectively reviewed. Imaging analysis was confined to the long and flat bones. CT scans were performed in five patients and MR imaging was performed in eight. Images were assessed for the following features on CT and MRI: the location and number of lesions; the presence of cortical destruction, endosteal scalloping, and a periosteal reaction on CT or MRI; the margin of soft tissue masses, the presence of bone marrow edema, and a ''budding'' appearance on MRI; and the presence of sclerotic margins or septations on CT. The involved skeletal sites were the pelvis (seven), femurs (five), humeri (two), tibias (two), fibula (one), clavicle (one), scapula (one), and sternum (one). Endosteal scalloping, a periosteal reaction, and a budding appearance were common on MRI or CT images. Although cortical destruction and the soft tissue lesion formation were rare, soft tissue masses had well-defined margins. Endosteal scalloping and a budding appearance with a periosteal reaction on CT and MRI may be helpful signs for differentiation of LCH from malignant tumors in adults. (orig.)

  18. Langerhans' cell histiocytosis: pathology, imaging and treatment of skeletal involvement

    Energy Technology Data Exchange (ETDEWEB)

    Azouz, E. Michel [University of Miami, Pediatric Radiology Section, Department of Radiology, Miami, FL (United States); Saigal, Gaurav [McGill University, Department of Medical Imaging, Quebec (Canada); Rodriguez, Maria M. [University of Miami, Department of Pathology, Miami, FL (United States); Podda, Antonello [University of Miami, Division of Pediatric Hematology/Oncology, Miami, FL (United States)

    2005-02-01

    Langerhans' cell histiocytosis (LCH) is manifested in a variety of ways, the most common being the eosinophilic granuloma, a localized, often solitary bone lesion that occurs predominantly in the pediatric age group. The hallmark of LCH is the proliferation and accumulation of a specific histiocyte: the Langerhans' cell. In bone this may cause pain and adjacent soft-tissue swelling, but some lesions are asymptomatic. LCH can involve any bone, but most lesions occur in the skull (especially the calvarium and temporal bones), the pelvis, spine, mandible, ribs, and tubular bones. Imaging diagnosis of the disease in bone is first based on the plain radiographic appearance, which is usually a central destructive, aggressive-looking lesion. In the skull, the lesions develop in the diploic space, are lytic, and their edges may be beveled, scalloped or confluent (geographic), or show a ''button sequestrum.'' Vertebral body involvement usually causes collapse, resulting in vertebra plana. With significant recent improvements in the quality of gamma cameras, imaging techniques, and in studying children, bone scintigraphy at diagnosis and on follow-up usually reveals the sites of active disease, especially when the involvement is polyostotic. CT and MR imaging are very useful in providing detailed cross-sectional anatomic detail of the involved bone, including the bone marrow and the adjacent soft tissues. CT is better suited for demonstrating bone detail and MR imaging for bone marrow and soft-tissue involvement. (orig.)

  19. Adult Multisystem Langerhans Cell Histiocytosis Presenting with Central Diabetes Insipidus Successfully Treated with Chemotherapy

    Directory of Open Access Journals (Sweden)

    Jung-Eun Choi

    2014-09-01

    Full Text Available We report the rare case of an adult who was diagnosed with recurrent multisystem Langerhans cell histiocytosis (LCH involving the pituitary stalk and lung who present with central diabetes insipidus and was successfully treated with systemic steroids and chemotherapy. A 49-year-old man visited our hospital due to symptoms of polydipsia and polyuria that started 1 month prior. Two years prior to presentation, he underwent excision of right 6th and 7th rib lesions for the osteolytic lesion and chest pain, which were later confirmed to be LCH on pathology. After admission, the water deprivation test was done and the result indicated that he had central diabetes insipidus. Sella magnetic resonance imaging showed a mass on the pituitary stalk with loss of normal bright spot at the posterior lobe of the pituitary. Multiple patchy infiltrations were detected in both lung fields by computed tomography (CT. He was diagnosed with recurrent LCH and was subsequently treated with inhaled desmopressin, systemic steroids, vinblastine, and mercaptopurine. The pituitary mass disappeared after two months and both lungs were clear on chest CT after 11 months. Although clinical remission in multisystem LCH in adults is reportedly rare, our case of adult-onset multisystem LCH was treated successfully with systemic chemotherapy using prednisolone, vinblastine, and 6-mercaptopurine, which was well tolerated.

  20. Radiographic skeletal survey and radionuclide bone scan in Langerhans cell histiocytosis of bone

    International Nuclear Information System (INIS)

    Nieuwenhuyse, J.P. van; Clapuyt, P.; Malghem, J.; Everarts, P.; Melin, J.; Pauwels, S.; Brichard, B.; Ninane, J.; Vermylen, C.; Cornu, G.

    1996-01-01

    Background. The lack of a consensus in the literature on the imaging strategy in Langerhans cell histiocytosis (LCH) bone lesions in childhood. Objective. To evaluate the relative value of radionuclide bone scan (RBS) and radiographic skeletal survey (RSS) in the detection of LCH bone lesions, both in the initial work-up of the disease and during the follow-up period. Materials and methods. Ten children with bone lesions evaluated by means of RSS and RBS in a retrospective study (1984-1993). Results. Fifty radiologically and/or scintigraphically abnormal foci were detected: 27 anomalies in the initial work-up (12 by both RSS and RBS, 8 by RSS only and 7 by RBS only) and 23 additional anomalies during follow-up (10 by both RSS and RBS, 10 by RSS only and 3 by RBS only). RSS+/RBS- lesions (n = 18) are more frequently encountered in the skull (P = 0.038), and more frequently lack radiologic signs of osteoblastic activity (P = 0.020), than RSS+/RBS+ lesions (n = 22). RSS-/RBS+ abnormalities (n = 10) were most frequently insignificant. Conclusion. In the initial work-up both RSS and RBS should be carried out, while in the follow-up only RSS should be performed. (orig.). With 2 figs., 4 tabs

  1. The natural history of skin-limited Langerhans cell histiocytosis: a single-institution experience.

    Science.gov (United States)

    Ehrhardt, Matthew J; Humphrey, Stephen R; Kelly, Michael E; Chiu, Yvonne E; Galbraith, Sheila S

    2014-11-01

    Prior reports of Langerhans cell histiocytosis (LCH) suggest that isolated skin involvement is rare and often progresses to systemic disease. More rapid access to pediatric subspecialty care has likely led to more frequent representation of this condition. The purpose of this study is to characterize the natural history of skin-limited LCH in an era of increased access to pediatric subspecialty care. A retrospective chart review was performed on all patients newly diagnosed with LCH between 2001 and 2012 at the Children's Hospital of Wisconsin. Extensive review of laboratory, physical examination, and imaging reports was performed and data collected for patients with biopsy-proven skin LCH. Sixteen individuals with skin-limited LCH were identified. The median age at onset of skin eruption was birth (range, birth to 6 mo), and median duration of follow-up was 19.5 months (range, 2 wk to 10 y) from diagnosis. One patient (6%) developed pituitary disease and 1 patient (6%) had refractory skin involvement. All others experienced complete resolution. For patients without progressive or refractory disease, resolution of skin findings occurred within 7 months from onset. Progression of skin-limited to multisystem LCH likely may be less frequent than previously described.

  2. Analysis of the BRAFV600E mutation in 19 cases of Langerhans cell histiocytosis in Japan.

    Science.gov (United States)

    Sasaki, Yuya; Guo, Ying; Arakawa, Fumiko; Miyoshi, Hiroaki; Yoshida, Noriaki; Koga, Yuhki; Nakashima, Kazutaka; Kurita, Daisuke; Niino, Daisuke; Seto, Masao; Ohshima, Koichi

    2017-09-01

    Langerhans cell histiocytosis (LCH) is a rare disease characterized by clonal proliferation of CD1a- and CD207 (langerin)-positive dendritic cells. Mutated BRAF (p.V600E) is observed in histiocyte-related diseases and dendritic cell-related diseases, including LCH. BRAFV600E is observed in some LCH cases and is thought to be involved in maintaining MAPK activation. We retrospectively analyzed BRAFV600E in 19 patients diagnosed with LCH. In our study, direct sequencing for exon 15, a mutation hotspot, demonstrated that 4 out of the 19 patients (21%) harbored a GTG > GAG (valine > glutamic acid) base substitution, which encodes BRAFV600E. The clinical impact of BRAFV600E in such diseases is unclear. The frequency of BRAFV600E in our LCH patients from Japan was lower than that reported in the United States and in Germany. However, reports from Asia tend to show a lower rate of the BRAFV600E mutation. These results imply the possibility of different genetic backgrounds in the pathogenesis of LCH across various ethnicities. We also performed an immunohistochemical analysis to detect BRAFV600E using the mutation-specific monoclonal antibody. However, immunohistochemical analysis failed to detect any mutated protein in any of the 4 BRAFV600E-positive cases. This implies that at present, BRAFV600E should be assessed by direct sequencing. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  3. Epstein-Barr virus-containing T-cell lymphoma presents with hemophagocytic syndrome mimicking malignant histiocytosis.

    Science.gov (United States)

    Su, I J; Hsu, Y H; Lin, M T; Cheng, A L; Wang, C H; Weiss, L M

    1993-09-15

    The previously designated malignant histiocytosis (MH) may include lymphoid neoplasms of T-cell lineage as well as patients with benign virus-associated hemophagocytic syndrome (VAHS). In this study, the association of Epstein-Barr virus (EBV) with T cell lymphomas which present with clinicopathologic features indistinguishable from malignant histiocytosis (MH) was investigated further. Four adult patients, three women and one man, were admitted because of fever, cutaneous lesions, hepatosplenomegaly, and jaundice. Laboratory examinations revealed pancytopenia, abnormal liver functions and coagulopathy. All patients ran a fulminant course terminating in a hemophagocytic syndrome within 1 month. Immunophenotypic study, Southern blot analysis, and in situ hybridization were performed on the specimens obtained from the four patients. The biopsy-necropsy specimens from skin, liver, spleen, and bone marrow showed infiltration of atypical large cells with reactive histiocytosis and florid hemophagocytosis activity. Based on the clinical and histologic findings, these cases would have been designated as MH by previous criteria. Immunophenotypic, Southern blot, and in situ hybridization studies, however, showed clonotypic proliferation of EBV genomes in the nuclei of the large atypical cells that expressed T-cell antigens. Therefore, these patients should be diagnosed as a recently described EBV-associated peripheral T-cell lymphoma (EBV-PTCL). EBV-PTCL may present with a fulminant hemophagocytic syndrome indistinguishable from the previously designated MH. This finding represents a step forward in our changing concept regarding MH, some of which only recently has been suggested to be of T-cell lymphoma origin. Differentiation from benign VAHS is clinically important. Features useful in this distinction are tabulated and discussed.

  4. Daam1 regulates fascin for actin assembly in mouse oocyte meiosis.

    Science.gov (United States)

    Lu, Yujie; Zhang, Yu; Pan, Meng-Hao; Kim, Nam-Hyung; Sun, Shao-Chen; Cui, Xiang-Shun

    2017-07-18

    As a formin protein, Daam1 (Dishevelled-associated activator of morphogenesis 1) is reported to regulate series of cell processes like endocytosis, cell morphology and migration via its effects on actin assembly in mitosis. However, whether Daam1 plays roles in female meiosis remains uncertain. In this study, we investigated the expression and functions of Daam1 during mouse oocyte meiosis. Our results indicated that Daam1 localized at the cortex of oocytes, which was similar with actin filaments. After Daam1 morpholino (MO) microinjection, the expression of Daam1 significantly decreased, which resulted in the failure of oocyte polar body extrusion. These results might be due to the defects of actin assembly, since the decreased fluorescence intensity of actin filaments in oocyte cortex and cytoplasm were observed. However, Daam1 knockdown seemed not to affect the meiotic spindle movement. In addition, we found that fascin might be the down effector of Daam1, since the protein expression of fascin decreased after Daam1 knockdown. Thus, our data suggested that Daam1 affected actin assembly during oocyte meiotic division via the regulation of fascin expression.

  5. Evolving radiological features of hypothalamo-pituitary lesions in adult patients with Langerhans cell histiocytosis (LCH)

    International Nuclear Information System (INIS)

    Makras, P.; Samara, C.; Antoniou, M.; Nikolakopoulou, Z.; Zetos, A.; Papadogias, D.; Piaditis, G.; Kaltsas, G.A.; Toloumis, G.; Andreakos, E.; Kontogeorgos, G.

    2006-01-01

    Langerhans cell histiocytosis (LCH) is a rare, systemic disease caused by monoclonal expansion of dendritic cells that shows a particular predilection for the hypothalamic-pituitary system (HPS). We studied the function (anterior and posterior pituitary hormonal secretion) and morphology using magnetic resonance imaging (MRI) of the HPS in 17 adult patients (seven males, median age 35 years, range 18-59 years) with multisystem LCH. We also evaluated the evolution of structural HPS abnormalities in relation to pituitary function and response to treatment in 12 of these patients during a median follow-up period of 3.75 years (range 1.5-10 years). Of the 17 patients, 14 (82%) had abnormal HPS imaging, and 12 (70%) had more than one area involved. Lack of the bright spot of the posterior pituitary lobe was typically found in all patients with the diagnosis of diabetes insipidus (DI). Eight patients (47%) had infundibular enlargement, six (35%) pituitary infiltration, four (24%) partially or completely empty sella, three (18%) hypothalamic involvement, and two (12%) infundibular atrophy. DI was found in 16 patients (94%) and anterior pituitary hormonal deficiency (APHD) in 10 patients (59%); two patients had single (12%) and 8 (47%) multiple APHD. During the follow-up period there was improvement of the initially demonstrated HPS pathology in seven (47%) patients, and five (33%) of them had received at least one form of treatment. APHD and DI persisted in all patients except in one in whom established gonadotrophin deficiency recovered. In summary, DI and APHD are very common in patients with multisystem LCH and are almost always associated with abnormal HPS imaging. (orig.)

  6. The value of bone scintigraphy in diagnosing of langerhans cells histiocytosis

    International Nuclear Information System (INIS)

    Shao Hong; Shi Meihua; Wu Jinchuan

    2004-01-01

    Purpose: To investigate the clinical value of bone scintigraphy in the diagnosis of Langerhans cells histiocytosis (LCH). Methods: Whole-body bone scintigraphy was performed in 23 patients, 16 males and 7 females, average age was 4.5+1.4, with histologic diagnosis of LCH. The clinical presentation varied from local mass (10 cases), tenderness (12 cases), othemorrhea (1 case), limb fatigue (3 cases), restriction of spinal activity (2 cases) to irregular fever, cough and rash (4 cases). 99Tcm-MDP was injected intravenously , the dose modified as age, according to the formula of [ adult dosage x [(age+l)/(age+7)] ] , and sedation was given to the young children who could not cooperate well. After 3 hours of administration whole-body bone scan was performed. Images were acquired using GE Millennium SPR, with a high-resolution low-energy collimator, 8 min/m sweep speed, matrix 1024 x 256, zoom 1. Results: 19 of 23 patients (82.6%) showed positive in their bone scan. 8 cases with cranial abnormal uptake, some of them exhibited peripheral high and central low uptake; clavicle, rib and pelvis involvements were 3 respectively; 2 cases in upper limb, 4 in lower limb, most lesions of limb were located in the diaphysis; spinal abnormal uptakes were seen in 5 patients, and 1 child had photon deficient area in the lower of sternium. Among 19 positive scintigram, single bone lesion was shown in 9 patients (47.3%), the most common lesion located in cranium (5 cases). Conclusion: Some characters of bone scintigraphy in LCH are useful in the diagnosis of this disease, and accompanied with comprehensive sensation of clinical manifestation of LCH, the diagnostic accuracy will be promoted. (authors)

  7. Central nervous system imaging in childhood Langerhans cell histiocytosis – a reference center analysis

    International Nuclear Information System (INIS)

    Porto, Luciana; Schöning, Stefan; Hattingen, Elke; Sörensen, Jan; Jurcoane, Alina; Lehrnbecher, Thomas

    2015-01-01

    The aim of our study was (1) to describe central nervous system (CNS) manifestations in children with Langerhans cell histiocytosis (LCH) based on images sent to a reference center and meeting minimum requirements and (2) to assess the inter-rater agreement of CNS-MRI results, which represents the overall reproducibility of this investigation. We retrospectively reviewed brain MRI examinations in children with LCH, for which MRI minimum requirements were met. Abnormalities were rated by two experienced neuroradiologists, and the inter-rater agreement was assessed. Out of a total of 94 imaging studies, only 31 MRIs met the minimum criteria, which included T2w, FLAIR, T1w images before/after contrast in at least two different section planes, and thin post contrast sagittal slices T1w through the sella. The most common changes were osseous abnormalities, followed by solid enlargement of the pineal gland, thickened enhancing stalk and signal changes of the dentate nucleus. Whereas inter-rater agreement in assessing most of the CNS lesions was relatively high (κ > 0.61), the application of minimum criteria often did not allow to evaluate the posterior pituitary. The diversity of radiological protocols from different institutions leads to difficulties in the diagnosis of CNS abnormalities in children with LCH. Although the inter-rater agreement between neuroradiologists was high, not all the LCH manifestations could be completely ruled out when using the minimum criteria. Brain MRIs should therefore follow LCH guideline protocols and include T1 pre-gadolinium sagittal images, and be centrally reviewed in order to improve the comparison of clinical trials

  8. Management and Outcome of Patients With Langerhans Cell Histiocytosis and Single-Bone CNS-Risk Lesions: A Multi-Institutional Retrospective Study

    NARCIS (Netherlands)

    Chellapandian, Deepak; Shaikh, Furqan; van den Bos, Cor; Somers, Gino R.; Astigarraga, Itziar; Jubran, Rima; Degar, Barbara; Carret, Anne-Sophie; Mandel, Karen; Belletrutti, Mark; Dix, David; Visser, Johannes; Abuhadra, Nour; Chang, Tiffany; Rollins, Barret; Whitlock, James; Weitzman, Sheila; Abla, Oussama

    2015-01-01

    Children with Langerhans cell histiocytosis (LCH) and single-bone CNS-risk lesions have been reported to be at increased risk of diabetes insipidus (DI), central nervous system neurodegeneration (CNS-ND), and recurrence of disease. However, it is unknown whether the addition of chemotherapy or

  9. Sinus histiocytosis with massive lymphadenopathy (Rosai-Dorfman disease): a clinicoradiological profile of three cases including two with skeletal disease

    International Nuclear Information System (INIS)

    Gupta, Priya; Babyn, Paul

    2008-01-01

    Originally described as sinus histiocytosis with massive lymphadenopathy, Rosai-Dorfman disease (RDD) is a rare histiocytic proliferative disorder with a distinctive microscopic appearance. A rare entity, RDD is often under-diagnosed because of a low index of suspicion by both radiologist and pathologist. Through this article, we wish to apprise radiologists of the spectrum of disease that can be encountered in this disorder. RDD can mimic other common childhood skeletal diseases including benign Langerhans cell histiocytosis and lymphoma. The clinical and radiological manifestations of RDD vary depending upon organ involvement, and its imaging features are often confused with those of other disorders. RDD should be considered in the differential diagnosis of unifocal and multifocal skeletal involvement caused by granulomatous diseases, infections, pseudogranulomatous lesions and malignancy. As long-term outcome is usually good, a conservative approach is justified in most cases. Contrasted with its typical appearance, presenting with bilateral symmetrical cervical adenopathy (as shown in one patient), we also report extranodal involvement of bone in two patients. Extranodal disease occurs along with concomitant nodal disease in about 43% of patients. In 23% of patients, isolated extranodal RDD can be seen, most commonly in the head and neck. In two of our patients, we observed extranodal involvement with skeletal involvement away from the head and neck not associated with lymphadenopathy. Skeletal involvement in RDD without lymphadenopathy is rare, occurring only in 2% of all the patients reported to date. (orig.)

  10. An unusual case of adult-onset multi-systemic Langerhans cell histiocytosis with perianal and incident thyroid involvement

    Directory of Open Access Journals (Sweden)

    Ozen Oz Gul

    2017-02-01

    Full Text Available Langerhans cell histiocytosis (LCH is a rare sporadic disease characterized by histiocytic neoplastic infiltration of various organ systems and a wide spectrum of clinical manifestations, ranging from benign and self-limiting to lethal. Herein, we report a rare case of adult-onset multi-systemic LCH in a 36-year-old male patient with an initial perianal presentation and incidental finding of subsequent thyroid gland involvement in the follow-up period. The patient with a history of perianal LCH treated with surgical excision and local radiotherapy was referred to our Endocrinology Department upon detection of hypermetabolic nodular lesions in the left lateral lobe of thyroid gland on positron emission tomography–computed tomography (PET/CT scan in the nineth month of follow-up. Current evaluation revealed euthyroid status, a hypoechoic solid lesion of 13 × 9 mm in size with irregular borders in the left thyroid lobe on thyroid USG and cytologic assessment of thyroid nodule. The patient was diagnosed with suspected, oncocytic lesion, Hashimoto thyroiditis or LCH. The patient underwent total thyroidectomy and pathological assessment confirmed the diagnosis of Langerhans cell histiocytosis. Assessments in the sixth month of postoperative follow-up revealed euthyroid status with no thyroid tissue remnants or pathological lymph node on thyroid USG. In view of the multifocal lesions indicating multi-system disease, a systemic chemotherapy protocol with combination of prednisone (PRED and vinblastine (VBL has been planned by the hematology department.

  11. Tattoo as art, the drivers behind the fascination and the decision to become tattooed.

    Science.gov (United States)

    Kierstein, Liz; Kjelskau, Kari C

    2015-01-01

    For many people, getting a tattoo is like purchasing art, and many professional and famous tattooists are artists who are acknowledged by colleagues and authorities. The history of tattooing goes back for thousands of years, and the reasons for getting tattooed are many. These permanent markings are always personal, they can be plain or elaborate, and they serve as amulets, healing and status symbols, declarations of love, signs of religion, adornments and even forms of punishment. Drivers behind the fascination of acquiring a tattoo may fall into four main groups, namely healing, affiliation, art and fashion. © 2015 S. Karger AG, Basel.

  12. Fascinating physics. An illustrated expedition from the universe until the world of the elementary particles

    International Nuclear Information System (INIS)

    Bahr, Benjamin; Riebe, Kristin; Resag, Joerg

    2013-01-01

    ''Fascinating physics'' is a picturesque expedition through 140 themes of classical and modern physics. On each one double-page to the reader is thereby offered a compact access in each one theme: From the aurora until the black hole, from the particle accelerator until the GPS system, from the curved space-time until the supersymmetry, from the oscillating dipole until Foucault's pendulum - a large variety of themes is taken up and carefully explained. Thereby the special strength of the book lies in the clear language and the explanations get along mostly without formulas - accompanied by breathtaking pictures, which lead the beauty of our world in front of the eyes.

  13. The fascination of the rare earths - then, now and in the future

    International Nuclear Information System (INIS)

    Wybourne, Brian G.

    2004-01-01

    The rare earths have long been a subject of fascination to chemists and physicists. Herein, I comment on some of the prehistory leading up to the advent of the Judd-Ofelt theory of the intensities of their remarkable spectra, the origins of the Judd-Ofelt theory and its early applications. I then consider subsequent developments and extensions of the theory, its current status and its relevance to current problems of interest in rare earth spectroscopy and the future of rare earth studies

  14. Graham Greene’s Journey Without Maps and the Fascination of the Abomination

    Directory of Open Access Journals (Sweden)

    John AIREY

    2009-07-01

    Full Text Available Le narrateur de ce récit de voyage se révèle fasciné par ce qui est abominable : maladies, crimes de guerre, cruauté et cauchemars sont les principaux exemples dans le texte. A ce sujet, il ouvre un dialogue critique avec ses deux principaux hypotextes, Heart of Darkness de Conrad et surtout The Blue Book, publication du gouvernement Britannique : l’abominable serait donc polysémique. Son voyage fait de l’arrière pays ‘primitif’ du Libéria un ‘texte’ scriptible. Parallèlement, il utilise la partie du pays explorée comme métaphore de l’inconscient : de la sorte il compare son périple au ‘voyage’ de Freud. La ‘civilisation’, souvent symbolisée par le Christianisme dans le récit, ferait fausse route car elle serait fondée sur le refoulement, voir la déformation d’une partie de la réalité : être sain d’esprit serait refuser d’accomplir ces actions et s’engager dans un dialogue avec ‘le père politique’ (Barthes. Le lecteur est incité à avouer sa fascination pour cette zone ténébreuse et donc à entreprendre sa propre exploration.The narrator of this travel book shows himself to be fascinated by what is abominable: disease, war crimes, cruelty and nightmares are the main examples in the text. He opens a critical dialogue on this subject with his two main hypotexts, Conrad’s Heart of Darkness and, especially, The Blue Book, a British government publication; the abomination is found to be polysemic. His journey transforms the supposedly primitive Liberian hinterland into a writerly text (Barthes. At the same time, the narrator uses the part of the country he is exploring as a metaphor for the unconscious; hence he compares his voyage to Freud’s ‘journey’. ‘Civilisation’, of which Christianity is often used as a symbol in the text, is on the wrong track according to the narrator since it is based on the repression, if not the distortion, of a part of reality. To be sane is to

  15. A Review on the Fascinating World of Insect Resources: Reason for Thoughts

    Directory of Open Access Journals (Sweden)

    R. K. Lokeshwari

    2010-01-01

    Full Text Available Insect resources are vast and diverse due to their enormous diversity. The exploitation and utilization of insect resources is broadly classified into four different categories. The first category is the insects of industrial resources. This level includes the utilization of silk worm, honeybee, lac insect, dye insect, and aesthetic insect. The second category is the utilization of insects for edible and therapeutic purposes. Insects are high in protein and many are rich sources of vitamins and minerals. The third category is the use of insects in forensic investigation. By analyzing the stages of succession of insects at first, rough estimation of the postmortem intervals can be done. The fourth category is the insects of ecological importance. Many insect species act as potential predators and parasites of destructive pests of insect order Lepidoptera, Diptera, and Orthoptera. Insects are also used as bioindicator to assess the cumulative effects of environmental stressors such as pollutants. Despites these fascinating benefits, insect resources are often neglected in India due to lack of proper documentation, less expertise, and advance enterprises in these fields. Hence, the paper reviews the different fascinating facets of insect resources in order to explore and utilize it in a sustainable way with reference to Indian region.

  16. Solitary Langerhans cell histiocytosis of the occipital condyle: a case report and review of the literature.

    Science.gov (United States)

    Teranishi, Yu; Shin, Masahiro; Yoshino, Masanori; Saito, Nobuhito

    2016-02-01

    Despite the recent advent of various radiographic imaging techniques, it is still very difficult to correctly distinguish a pediatric osteolytic lesion in the occipital condyle, which makes it further complicated to decide on the necessity of and the adequate timing for radical resection and craniocervical fusions. To establish a legitimate therapeutic strategy for this deep-seated lesion, surgical biopsy is a reasonable choice for first-line intervention. The choice of surgical approach becomes very important because a sufficient amount of histological specimen must be obtained to confirm the diagnosis but, ideally, the residual bony structures and the muscular structures should be preserved so as not to increase craniocervical instability. In this report, we present our experience with a case of solitary Langerhans cell histiocytosis (LCH) involving the occipital condyle that was successfully treated with minimally invasive surgical biopsy with a far lateral condylar approach supported by preoperative 3D computer graphic simulation. An 8-year-old girl presented with neck pain. Magnetic resonance imaging and computed tomography (CT) revealed an osteolytic lesion of the left occipital condyle. At surgery, the patient was placed in the prone position. A 3-cm skin incision was made in the posterior auricular region, and the sternocleidomastoid and splenius capitis muscles were dissected in the middle of the muscle bundle along the direction of the muscle fiber. Under a navigation system, we approached the occipital condyle through the space between the longissimus capitis muscle and the posterior belly of the digastric muscle and lateral to the superior oblique muscle, verifying each muscle at each depth of the surgical field and, finally, obtained sufficient surgical specimen. After the biopsy, her craniocervical instability had not worsened, and chemotherapy was performed. Twelve weeks after chemotherapy, her neck pain had gradually disappeared along with her

  17. High-resolution CT in eosinophilic granuloma (histiocytosis X) of the lung

    International Nuclear Information System (INIS)

    Godwin, J.D.; Buschman, D.L.; Moore, A.D.A.; Muller, N.L.; Naidich, D.P.; Carvalho, C.R.R.; Takasugi, J.E.; Schmidt, R.A.

    1988-01-01

    Eosinophilic granuloma of the lung is fascinating but poorly understood. Computed tomographic (CT) scans in 18 cases (11 high resolution) showed a variety of striking patterns: cysts up to 4 cm with thin or indiscernible walls, ranging from a few lesions to confluent honeycombing; retriculonodular infiltrate; and nodules 2 mm-2cm, sometimes cavitated. CT showed that the ill-defined lucencies barely visible on radiographs are indeed cysts, rather than preserved normal lung surrounded by infiltrate. High-resolution CT showed that some of the early, small nodules were concentrated along terminal bronchioles within the secondary lobules. The differential diagnosis includes sarcoidosis and idiopathic fibrosis, but the prominent cystic abnormality and the lack of peripheral concentration help to distinguish eosinophilic granuloma

  18. Total pleurectomy as the surgical treatment for recurrent secondary spontaneous pneumothorax in a child with severe pulmonary Langerhans cells histiocytosis.

    Science.gov (United States)

    Abdul Aziz, Dayang Anita; Abdul Rahman, Nur Afdzillah; Tang, Swee Fong; Abdul Latif, Hasniah; Zaki, Faizah Mohd; Annuar, Zulfiqar Mohd; Alias, Hamidah; Abdul Latiff, Zarina

    2011-12-01

    Pulmonary Langerhans cell histiocytosis (LCH) in children is more extensive and is a rare cause of spontaneous secondary pneumothorax (SSP) which tends to be recurrent and refractory to conventional treatment. Its occurrence in paediatric patients posed great challenge to the choice of surgical management. Surgery in the form of pleurodesis is only considered if SSP does not improve after chemotherapy and after considering all relevant risk and benefits of surgery to patients. Chemical pleurodesis will not give the expected effect to eradicate SSP in this patient. Therefore mechanical pleurodesis is the treatment of choice. There are various techniques to perform mechanical pleurodesis; from pleural abrasion to pleurectomy. In the authors' experience, bilateral total pleurectomy provided the best outcome for this 9-year-old patient with persistent respiratory distress from SSP due to extensive pulmonary LCH.

  19. Langerhans′ cell histiocytosis involving posterior elements of the dorsal spine: An unusual cause of extradural spinal mass in an adult

    Directory of Open Access Journals (Sweden)

    Devendra K Tyagi

    2011-01-01

    Full Text Available Langerhans cell histiocytosis (LCH is a clonal proliferation of Langerhans cells occurring as an isolated lesion or as part of a systemic proliferation. It is commoner in children younger than 10 years of age with sparing of the posterior elements in more than 95% of cases. We describe a case of LCH in an adult female presenting with paraplegia. MRI revealed a well-defined extradural contrast enhancing mass at D2-D4 vertebral level involving the posterior elements of spine. D2-5 laminectomy with excision of lesion was performed which lead to marked improvement of patients neurological status. Histopathology was suggestive of eosinophilic granuloma. We describe the case, discuss its uniqueness and review the literature on this rare tumor presentation.

  20. Central diabetes insipidus as a very late relapse limited to the pituitary stalk in Langerhans cell histiocytosis.

    Science.gov (United States)

    Nakagawa, Shunsuke; Shinkoda, Yuichi; Hazeki, Daisuke; Imamura, Mari; Okamoto, Yasuhiro; Kawakami, Kiyoshi; Kawano, Yoshifumi

    2016-07-01

    Central diabetes insipidus (CDI) and relapse are frequently seen in multifocal Langerhans cell histiocytosis (LCH). We present two females with multifocal LCH who developed CDI 9 and 5 years after the initial diagnosis, respectively, as a relapse limited to the pituitary stalk. Combination chemotherapy with cytarabine reduced the mass in the pituitary stalk. Although CDI did not improve, there has been no anterior pituitary hormone deficiency (APHD), neurodegenerative disease in the central nervous system (ND-CNS) or additional relapse for 2 years after therapy. It was difficult to predict the development of CDI in these cases. CDI might develop very late in patients with multifocal LCH, and therefore strict follow-up is necessary, especially with regard to symptoms of CDI such as polydipsia and polyuria. For new-onset CDI with LCH, chemotherapy with cytarabine might be useful for preventing APHD and ND-CNS.

  1. Quantitative PCR and immunohistochemical analyses of HMGB1 and RAGE expression in canine disseminated histiocytic sarcoma (malignant histiocytosis).

    Science.gov (United States)

    Sterenczak, Katharina A; Kleinschmidt, Sven; Wefstaedt, Patrick; Eberle, Nina; Hewicker-Trautwein, Marion; Bullerdiek, Jörn; Nolte, Ingo; Murua Escobar, Hugo

    2011-05-01

    Disorders of histiocytic origin affecting humans and dogs share various similarities. Canine disseminated histiocytic sarcoma (DHS) (formerly known as malignant histiocytosis) is an aggressive neoplasm of interstitial dendritic cells (DCs). The receptor for glycation end products (RAGE) and the high mobility group box1 protein (HMGB1) have been shown to be required for the maturation and migration of DCs. Thus, deregulation of the expression of these genes could have a major effect on the progression of histiocytic disorders. Neoplastic canine DHS samples and non-neoplastic control samples were analysed immunohistochemically and via real-time PCR. Significant down-regulation of RAGE in the lung tumour samples and down-regulation of HMGB1 in the lung, lymph node and spleen tumour samples were detected compared to their non-neoplastic counterparts. RAGE and HMGB1 expression down-regulation in canine DHS points to a role in the progression of histiocytic disorders.

  2. Whole-body MRI in children with Langerhans cell histiocytosis for the evaluation of the skeletal system

    International Nuclear Information System (INIS)

    Steinborn, M.; Woertler, K.; Rummeny, E.J.; Nathrath, M.; Schoeniger, M.; Hahn, H.

    2008-01-01

    Purpose: the usefulness of whole-body MRI (WB-MRI) for the detection of skeletal lesions in patients with Langerhans cell histiocytosis should be documented on the basis of case presentations. Materials and methods: in six patients with histologically proven Langerhans cell histiocytosis, 14 WB-MRI examinations were performed to evaluate the skeletal system within disease staging (6 primary, 8 follow-up examinations). The examinations were performed on a 1.5 Tesla, 32-channel whole-body scanner. The examination protocol consisted of T1-weighted and STIR sequences in coronal and sagittal orientation. For comparison, radiographs of the initial skeletal lesions and those that were additionally detected on WB-MRI were available. Results: in 4 patients no additional skeletal lesions were found on WB-MRI besides the initial lesion leading to the diagnosis of unifocal single system disease. In 2 patients WB-MRI was able to identify additional skeletal lesions. In a 5 1/2 year-old boy with the primary lesion located in the cervical spine, a second lesion was detected in the lumbar spine on the initial scan and in the skull and proximal femur during follow-up examination. In a 12 year-old girl with a primary lesion of the thoracic spine, WB-MRI diagnosed additional lesions in the pelvic bone and the tibia. In both patients the diagnosis of multifocal skeletal involvement led to chemotherapy. During follow-up examination, the healing response under therapy could be demonstrated. Comparison with conventional imaging showed that especially lesions located in the spine or the pelvis were not detectable on radiographs even when knowing the MR results. (orig.)

  3. Neuroendocrine tumors: fascination and infrequency Tumores neuroendocrinos: fascinación e infrecuencia

    Directory of Open Access Journals (Sweden)

    M. J. Varas Lorenzo

    2009-03-01

    Full Text Available In this article, I review and update of gastro-entero-pancreatic neuroendocrine tumors, which so much fascination have risen among healthcare providers on grounds of their infrequency, hormonal syndromes, and high survival rate, is performed based on references from the past fifteen years.Se efectúa una revisión y puesta al día, basándose en citas bibliográficas de los últimos quince años, de los tumores neuroendocrinos gastroenteropancreáticos, que tanta fascinación han provocado en el estamento médico por su infrecuencia, síndromes hormonales y supervivencia elevada.

  4. Heiko Schmid, Economy of fascination. Dubai and Las Vegas as Themed Urban Landscapes

    OpenAIRE

    Ghorra-Gobin, Cynthia

    2010-01-01

    Cet ouvrage résulte d’une recherche initialement intitulée les « mondes artificiels » à partir d’un travail de terrain mené dans deux villes localisées en zone désertique (Dubai, (D) et Las Vegas (LV)), ce qui a priori justifiait le choix de l’adjectif « artificiel ». L’introduction précise que ces deux villes – ne pouvant être présentées comme de simples « destinations touristiques » – ont toutefois permis d’illustrer la thématique de l’économie de la fascination et de discuter des ressorts ...

  5. Fascination and Social Togetherness–-Discussions about Spice Smoking on a Swedish Internet Forum

    Directory of Open Access Journals (Sweden)

    Anette Kjellgren

    2013-01-01

    Full Text Available Spice is a smoking mixture containing synthetic cannabinoids with psychoactive effects similar to herbal cannabis. It is sold on the Internet and has become popular among young people. The purpose of the present study was to investigate experiences of intoxication induced by Spice, as described on a Swedish internet-based discussion forum. A systematic search yielded 40 reports, which were analyzed using phenomenological method. A total of 7 themes (composed of 27 categories emerged from the analysis: 1. Spice use as social ritual; 2. Social secretiveness; 3. Intoxication remarks; 4. Well-being and elation; 5. Altered perception of reality; 6. Fears and coping; 7. Unpleasant physical effects. The results show that smoking was a social activity mostly carried out in small peer-groups, and that the substances induced strong intoxication with both positive and negative effects. Despite fears and unpleasant effects, the intoxication was often considered fascinating and rewarding.

  6. Fascination and Social Togetherness—Discussions about Spice Smoking on a Swedish Internet Forum

    Science.gov (United States)

    Kjellgren, Anette; Henningsson, Helena; Soussan, Christophe

    2013-01-01

    Spice is a smoking mixture containing synthetic cannabinoids with psychoactive effects similar to herbal cannabis. It is sold on the Internet and has become popular among young people. The purpose of the present study was to investigate experiences of intoxication induced by Spice, as described on a Swedish internet-based discussion forum. A systematic search yielded 40 reports, which were analyzed using phenomenological method. A total of 7 themes (composed of 27 categories) emerged from the analysis: 1. Spice use as social ritual; 2. Social secretiveness; 3. Intoxication remarks; 4. Well-being and elation; 5. Altered perception of reality; 6. Fears and coping; 7. Unpleasant physical effects. The results show that smoking was a social activity mostly carried out in small peer-groups, and that the substances induced strong intoxication with both positive and negative effects. Despite fears and unpleasant effects, the intoxication was often considered fascinating and rewarding. PMID:24324336

  7. Fascination and Social Togetherness-Discussions about Spice Smoking on a Swedish Internet Forum.

    Science.gov (United States)

    Kjellgren, Anette; Henningsson, Helena; Soussan, Christophe

    2013-01-01

    Spice is a smoking mixture containing synthetic cannabinoids with psychoactive effects similar to herbal cannabis. It is sold on the Internet and has become popular among young people. The purpose of the present study was to investigate experiences of intoxication induced by Spice, as described on a Swedish internet-based discussion forum. A systematic search yielded 40 reports, which were analyzed using phenomenological method. A total of 7 themes (composed of 27 categories) emerged from the analysis: 1. Spice use as social ritual; 2. Social secretiveness; 3. Intoxication remarks; 4. Well-being and elation; 5. Altered perception of reality; 6. Fears and coping; 7. Unpleasant physical effects. The results show that smoking was a social activity mostly carried out in small peer-groups, and that the substances induced strong intoxication with both positive and negative effects. Despite fears and unpleasant effects, the intoxication was often considered fascinating and rewarding.

  8. Langerhans cell histiocytosis or tuberculosis on a medieval child (Oppidum de la Granède, Millau, France - 10th-11th centuries AD).

    Science.gov (United States)

    Colombo, Antony; Saint-Pierre, Christophe; Naji, Stephan; Panuel, Michel; Coqueugniot, Hélène; Dutour, Olivier

    2015-06-01

    In 2008, a skeleton of a 1 - 2.5-year-old child radiocarbon dated from the 10th - 11th century AD was discovered on the oppidum of La Granède (Millau, France). It presents multiple cranial osteolytic lesions having punched-out or geographical map-like aspects associated with sequestrum and costal osteitis. A multi 3D digital approach (CT, μCT and virtual reconstruction) enabled us to refine the description and identify the diploic origin of the lytic process. Furthermore, precise observation of the extent of the lesions and associated reorganization of the skeletal micro-structure were possible. From these convergent pieces of evidence, the differential diagnosis led to three possibilities: Langerhans cell histiocytosis, tuberculosis, or Langerhans cell histiocytosis and tuberculosis. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Histiocytosis versus (Hand-Schuller-Christian disease) - a case report; Histiocitose versus (sindrome de Hand-Schuller-Christian) - relato de caso

    Energy Technology Data Exchange (ETDEWEB)

    Carneiro Filho, Jose Olimar; Leite, Marta Santos [Hospital Geral de Fortaleza, CE (Brazil). Clinica Radiologica Beroaldo Jurema, Fortaleza, CE (Brazil)]. E-mail: olimar_carneiro@hotmail.com; Andrade Neto, Jose Moacyr [Hospital Universitario Lauro Wanderley, Joao Pessoa, PB (Brazil). Clinica Medica

    2002-04-01

    The authors report a case of a 4-year-old girl with headache, irritability, othorrea and unilateral exophtalmus. Computed tomography and plain films showed large lytic areas in the vault and base of the skull. No other bones were involved. The diagnosis of histiocytosis X (Hand-Schuller-Christian disease) was confirmed by bone marrow biopsy. This paper presents the cytological and radiological findings of this patient as well as a review of the literature. (author)

  10. Fascin-1 knock-down of human glioma cells reduces their microvilli/filopodia while improving their susceptibility to lymphocyte-mediated cytotoxicity

    Science.gov (United States)

    Hoa, Neil T; Ge, Lisheng; Erickson, Kate L; Kruse, Carol A; Cornforth, Andrew N; Kuznetsov, Yurii; McPherson, Alex; Martini, Filippo; Jadus, Martin R

    2015-01-01

    Cancer cells derived from Glioblastoma multiforme possess membranous protrusions allowing these cells to infiltrate surrounding tissue, while resisting lymphocyte cytotoxicity. Microvilli and filopodia are supported by actin filaments cross-linked by fascin. Fascin-1 was genetically silenced within human U251 glioma cells; these knock-down glioma cells lost their microvilli/filopodia. The doubling time of these fascin-1 knock-down cells was doubled that of shRNA control U251 cells. Fascin-1 knock-down cells lost their transmigratory ability responding to interleukin-6 or insulin-like growth factor-1. Fascin-1 silenced U251 cells were more easily killed by cytolytic lymphocytes. Fascin-1 knock-down provides unique opportunities to augment glioma immunotherapy by simultaneously targeting several key glioma functions: like cell transmigration, cell division and resisting immune responses. PMID:25901196

  11. High resolution gamma-ray spectroscopy and the fascinating angular momentum realm of the atomic nucleus

    International Nuclear Information System (INIS)

    Riley, M A; Simpson, J; Paul, E S

    2016-01-01

    In 1974 Aage Bohr and Ben Mottelson predicted the different ‘phases’ that may be expected in deformed nuclei as a function of increasing angular momentum and excitation energy all the way up to the fission limit. While admitting their picture was highly conjectural they confidently stated ‘...with the ingenious experimental approaches that are being developed, we may look forward with excitement to the detailed spectroscopic studies that will illuminate the behaviour of the spinning quantised nucleus’ . High resolution gamma-ray spectroscopy has indeed been a major tool in studying the structure of atomic nuclei and has witnessed numerous significant advances over the last four decades. This article will select highlights from investigations at the Niels Bohr Institute, Denmark, and Daresbury Laboratory, UK, in the late 1970s and early 1980s, some of which have continued at other national laboratories in Europe and the USA to the present day. These studies illustrate the remarkable diversity of phenomena and symmetries exhibited by nuclei in the angular momentum–excitation energy plane that continue to surprise and fascinate scientists. (invited comment)

  12. Fascinating interaction of the ammonium cation with [2.2.2]paracyclophane: experimental and theoretical study

    Science.gov (United States)

    Makrlík, Emanuel; Sýkora, David; Böhm, Stanislav; Kvíčalová, Magdalena; Vaňura, Petr

    2018-05-01

    By means of electrospray ionisation mass spectrometry, it was evidenced experimentally that the ammonium cation (NH4+) reacts with the electroneutral [2.2.2]paracyclophane ligand (C24H24) to form the cationic complex [NH4(C24H24)]+. Moreover, applying quantum chemical calculations, the most probable conformation of the proven [NH4(C24H24)]+ complex was solved. In the complex [NH4(C24H24)]+ having a symmetry very close to C3, the 'central' cation NH4+ is coordinated by three strong bifurcated intramolecular hydrogen bonds to the corresponding six carbon atoms from the three benzene rings of [2.2.2]paracyclophane via cation-π interaction. Finally, the interaction energy, E(int), of the considered complex [NH4(C24H24)]+ was evaluated as -625.8 kJ/mol, confirming the formation of this fascinating complex species as well. It means that the [2.2.2]paracyclophane ligand can be considered as an effective receptor for the ammonium cation in the gas phase.

  13. Quirky quarks. A cartoon guide to the fascinating realm of physics

    Energy Technology Data Exchange (ETDEWEB)

    Bahr, Benjamin; Lemmer, Boris; Piccolo, Rina

    2016-07-01

    Do you love quantum physics, cosmology, and the humor behind the popular television show The Big Bang Theory? Have you been on the lookout for a fun, non-technical explanation of the science behind things like time travel, wormholes, antimatter, and dark energy? You'll find all of that, and more, inside this fact-filled, cartoon-packed book. In Quirky Quarks: A Cartoon Guide to the Fascinating Realm of Physics you'll get: The latest science behind the mysteries of our universe explained in common everyday language. A major dose of cartoons, comics, and humor. A good grasp on the often-bizarre nature of reality. Start reading and you'll find that hard science does not have to be hard. Whether you're a teacher, a physicist, or just a lover of the curious, this is the book that delivers the facts in an engaging and entertaining cartoon world inhabited by two dogs, a cat, and some very quirky quarks which you might know from The Particle Zoo. With cutting edge science articles by physicists Boris Lemmer and Benjamin Bahr, and drawings by cartoonist Rina Piccolo, this may be the most fun science reading you're likely to find out there.

  14. Quirky quarks. A cartoon guide to the fascinating realm of physics

    International Nuclear Information System (INIS)

    Bahr, Benjamin; Lemmer, Boris; Piccolo, Rina

    2016-01-01

    Do you love quantum physics, cosmology, and the humor behind the popular television show The Big Bang Theory? Have you been on the lookout for a fun, non-technical explanation of the science behind things like time travel, wormholes, antimatter, and dark energy? You'll find all of that, and more, inside this fact-filled, cartoon-packed book. In Quirky Quarks: A Cartoon Guide to the Fascinating Realm of Physics you'll get: The latest science behind the mysteries of our universe explained in common everyday language. A major dose of cartoons, comics, and humor. A good grasp on the often-bizarre nature of reality. Start reading and you'll find that hard science does not have to be hard. Whether you're a teacher, a physicist, or just a lover of the curious, this is the book that delivers the facts in an engaging and entertaining cartoon world inhabited by two dogs, a cat, and some very quirky quarks which you might know from The Particle Zoo. With cutting edge science articles by physicists Boris Lemmer and Benjamin Bahr, and drawings by cartoonist Rina Piccolo, this may be the most fun science reading you're likely to find out there.

  15. High resolution gamma-ray spectroscopy and the fascinating angular momentum realm of the atomic nucleus

    Science.gov (United States)

    Riley, M. A.; Simpson, J.; Paul, E. S.

    2016-12-01

    In 1974 Aage Bohr and Ben Mottelson predicted the different ‘phases’ that may be expected in deformed nuclei as a function of increasing angular momentum and excitation energy all the way up to the fission limit. While admitting their picture was highly conjectural they confidently stated ‘...with the ingenious experimental approaches that are being developed, we may look forward with excitement to the detailed spectroscopic studies that will illuminate the behaviour of the spinning quantised nucleus’. High resolution gamma-ray spectroscopy has indeed been a major tool in studying the structure of atomic nuclei and has witnessed numerous significant advances over the last four decades. This article will select highlights from investigations at the Niels Bohr Institute, Denmark, and Daresbury Laboratory, UK, in the late 1970s and early 1980s, some of which have continued at other national laboratories in Europe and the USA to the present day. These studies illustrate the remarkable diversity of phenomena and symmetries exhibited by nuclei in the angular momentum-excitation energy plane that continue to surprise and fascinate scientists.

  16. The neural representation of typical and atypical experiences of negative images: comparing fear, disgust and morbid fascination

    Science.gov (United States)

    Lindquist, Kristen A.; Adebayo, Morenikeji; Barrett, Lisa Feldman

    2016-01-01

    Negative stimuli do not only evoke fear or disgust, but can also evoke a state of ‘morbid fascination’ which is an urge to approach and explore a negative stimulus. In the present neuroimaging study, we applied an innovative method to investigate the neural systems involved in typical and atypical conceptualizations of negative images. Participants received false feedback labeling their mental experience as fear, disgust or morbid fascination. This manipulation was successful; participants judged the false feedback correct for 70% of the trials on average. The neuroimaging results demonstrated differential activity within regions in the ‘neural reference space for discrete emotion’ depending on the type of feedback. We found robust differences in the ventrolateral prefrontal cortex, the dorsomedial prefrontal cortex and the lateral orbitofrontal cortex comparing morbid fascination to control feedback. More subtle differences in the dorsomedial prefrontal cortex and the lateral orbitofrontal cortex were also found between morbid fascination feedback and the other emotion feedback conditions. This study is the first to forward evidence about the neural representation of the experimentally unexplored state of morbid fascination. In line with a constructionist framework, our findings suggest that neural resources associated with the process of conceptualization contribute to the neural representation of this state. PMID:26180088

  17. The fascination for the circle. Commentary on the paragraphs 13, 14 and 15 of The birth of tragedy

    Directory of Open Access Journals (Sweden)

    Julián Santos Guerrero

    2014-07-01

    Full Text Available The article tries to fix the attention on the functioning of the figure of the circle inside the thought of the young Nietzsche of The birth of tragedy.  At the same time, in it there is a thesis about the origin of the fascination that the above mentioned figure exercises in the Nietzschean text

  18. Fascin Is Critical for the Maintenance of Breast Cancer Stem Cell Pool Predominantly via the Activation of the Notch Self-Renewal Pathway.

    Science.gov (United States)

    Barnawi, Rayanah; Al-Khaldi, Samiyah; Majed Sleiman, Ghida; Sarkar, Abdullah; Al-Dhfyan, Abdullah; Al-Mohanna, Falah; Ghebeh, Hazem; Al-Alwan, Monther

    2016-12-01

    An emerging dogma shows that tumors are initiated and maintained by a subpopulation of cancer cells that hijack some stem cell features and thus referred to as "cancer stem cells" (CSCs). The exact mechanism that regulates the maintenance of CSC pool remains largely unknown. Fascin is an actin-bundling protein that we have previously demonstrated to be a major regulator of breast cancer chemoresistance and metastasis, two cardinal features of CSCs. Here, we manipulated fascin expression in breast cancer cell lines and used several in vitro and in vivo approaches to examine the relationship between fascin expression and breast CSCs. Fascin knockdown significantly reduced stem cell-like phenotype (CD44 hi /CD24 lo and ALDH + ) and reversal of epithelial to mesenchymal transition. Interestingly, expression of the embryonic stem cell transcriptional factors (Oct4, Nanog, Sox2, and Klf4) was significantly reduced when fascin expression was down-regulated. Functionally, fascin-knockdown cells were less competent in forming colonies and tumorspheres, consistent with lower basal self-renewal activity and higher susceptibility to chemotherapy. Fascin effect on CSC chemoresistance and self-renewability was associated with Notch signaling. Activation of Notch induced the relevant downstream targets predominantly in the fascin-positive cells. Limiting-dilution xenotransplantation assay showed higher frequency of tumor-initiating cells in the fascin-positive group. Collectively, our data demonstrated fascin as a critical regulator of breast CSC pool at least partially via activation of the Notch self-renewal signaling pathway and modification of the expression embryonic transcriptional factors. Targeting fascin may halt CSCs and thus presents a novel therapeutic approach for effective treatment of breast cancer. Stem Cells 2016;34:2799-2813 Video Highlight: https://youtu.be/GxS4fJ_Ow-o. © 2016 AlphaMed Press.

  19. Pulmonary langerhans cell histiocytosis in adults: high-resolution CT - pathology comparisons and evolutional changes at CT

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyo Jin; Lee, Ho Yun; Kim, Tae Sung [Sungkyunkwan University School of Medicine, Department of Radiology and Center for Imaging Science, Samsung Medical Center, Seoul (Korea, Republic of); Lee, Kyung Soo [Sungkyunkwan University School of Medicine, Department of Radiology and Center for Imaging Science, Samsung Medical Center, Seoul (Korea, Republic of); Samsung Medical Center, Department of Radiology, Seoul (Korea, Republic of); Johkoh, Takeshi [Kinki Central Hospital of Mutual Aid Association of Public School Teachers, Department of Radiology, Hyoko (Japan); Tomiyama, Noriyuki [Osaka University Graduate School of Medicine, Department of Radiology, Osaka (Japan); Han, Joungho [Sungkyunkwan University School of Medicine, Department of Pathology, Samsung Medical Center, Seoul (Korea, Republic of)

    2011-07-15

    To compare high-resolution (HR) CT and histopathological findings and to evaluate serial CT findings in pulmonary Langerhans cell histiocytosis (PLCH). We reviewed CT of lung lesions in 27 adults (M:F = 20:7, mean age, 41 {+-} 12.3 years) with PLCH. After evaluating lung abnormalities including nodules, micronodules, thick-walled, thin-walled, and bizarre-shaped cysts and reticulation, observers compared CT findings obtained at lung biopsy sites with histopathological findings. The final CT was compared with the initial CT to determine disease extent changes. The most frequently observed patterns of lung abnormalities were micronodules (n = 24, 89%), thick-walled (n = 22, 82%), and thin-walled (n = 22, 82%) cysts. Even thin-walled and bizarre cysts harboured active inflammatory Langerhans cell sheets and eosinophils in their walls. In thin-walled cysts, we noted pericystic inflammatory cell infiltrations along the alveolar walls, as well as pericystic emphysema. Thin-walled or bizarre cysts demonstrated a tendency to coalesce with surrounding cysts via their cystic wall destruction. Fourteen (52%) patients showed improvement and nine (33%) showed progressing disease. More than half of patients with pulmonary PLCH show improvement at follow-up CT. Even thin-walled cysts harbour active inflammatory cells on histopathology and exhibit improvement at follow-up CT. (orig.)

  20. Localized pulmonary crystal-storing histiocytosis complicating pulmonary mucosa-associated lymphoid tissue lymphoma presenting with multiple mass lesions.

    Science.gov (United States)

    Kokuho, Nariaki; Terasaki, Yasuhiro; Kunugi, Shinobu; Onda, Naomi; Urushiyama, Hirokazu; Terasaki, Mika; Hino, Mitsunori; Gemma, Akihiko; Hatori, Tsutomu; Shimizu, Akira

    2017-07-01

    Crystal-storing histiocytosis (CSH) is an uncommon finding in lymphoplasmacytic disorders that presents histiocytes with abnormal intralysosomal accumulations of immunoglobulin light chains as crystals of unknown etiology. A 38-year-old woman with antiphospholipid syndrome had a surgical lung biopsy because of multiple lung mass lesions. In a right middle lobe lesion, lymphoplasmacytic cells had a monocytoid appearance, destructive lymphoepithelial lesions, and positive immunoglobulin heavy chain (IGH) gene rearrangements. A right upper lobe lesion manifested proliferating rounded histiocytes with abundant, deeply eosinophilic cytoplasm and negative IGH gene rearrangements. Electron microscopy and mass spectrometry revealed a case of pulmonary CSH: abnormal proliferation of the immunoglobulin κ chain of a variable region that may be crystallized within plasma cells and histiocytes. We report a rare case of localized pulmonary CSH complicating pulmonary mucosa-associated lymphoid tissue lymphoma with multiple mass lesions. We demonstrate advances in the understanding of the pathogenesis of CSH by various analyses of these lesions. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. Smart Materials in Architecture: Useful Tools with Practical Applications or Fascinating Inventions for Experimental Design?

    Science.gov (United States)

    Konarzewska, Bogusława

    2017-10-01

    For at least several decades smart or so-called intelligent materials, being the result of great advancements in material engineering, appear in architecture in different applications. Most of them are called “smart” because of their inherent properties: a real-time response to environmental stimuli. There are also those considered to be “smart” due to smart design: their original structure or the composition of their materials are in nanoscale, providing them with unique properties. Colour changes, physical states, temperature or shape-always repeatable and reversible - make these materials attractive to architects, both from a visual and a practical point of view. Their spectacular applications often inspire architects, scientists and artists to create, for instance, city displays revealing various shapes and figures according to daily weather conditions; thermochromics urban seats that reflect peoples’ presence; wallpaper with organic patterns that glow in darkness, and many others. On the other hand, more practical projects are being developed, such as “switchable” partition glass walls (that is, we can turn them on and they change their transparency while switching on or off: electrochromic glass is a good example). Other concepts include self-cleaning building envelopes; self-repairing concrete; phase-changing materials diminishing cooling loads in the buildings; energy-generating highways; materials that harden at the moment of impact thus withstanding exceptionally great forces; shape memory alloys playing the role of actuators-opening and - closing façade louvers or thin polymer films mimicking the function of living skin, adopted as a building envelope. All those projects result from the fascination of designers with the possibility to create materials and, in effect, a complex environment that is active, “flexible”, and adapts to changing conditions and users’ needs and is compatible with real, natural environments. Smart materials

  2. A knitting legacy: Linda Newington opens up the doors to the University of Southampton’s fascinating knitting collections

    OpenAIRE

    Newington, Linda

    2011-01-01

    Our fascination with the knitwear of the past seems to know no bounds - the classic, elegant knits of yesteryear continue to inspire and influence designers and knitters alike. Working to collect, preserve and share these patterns is the University of Southampton Library, whose Knitting Collections contain more than 12,000 patterns from the early 20th century to the present day.The Library holds the resources of three renowned figures from the world of knitting: Montse Stanley, Richard Ruttan...

  3. Sinus histiocytosis with massive lymphadenopathy Rosai-Dorfman's disease as cause of isolated hilar lymphadenopathy and complete remission after high dose steroid

    International Nuclear Information System (INIS)

    Al-Jahdali, Hamdan H.; Al-Shirawi, Nehad N.; Bamefleh, Hana S.; Yamani, Nizar M.

    2008-01-01

    Rosai-Dorfman's Disease, also known as sinus histiocytosis with massive lymphadenopathy SHML, is a rare histiocytic proliferative disorder and a distinct clinic-pathological feature of unknown origin. Painless cervical lymphadenopathy is the most common clinical presentation. Different treatment modalities have been tried with variable responses, however, there is no consensus on the best modality of treatment. Here, we present a case report of SHML causing isolated hilar lymphadenopathy with complete remission for more than 6 years, after a short course of high dose steroid dexamethasone 20 mg daily for 3 days. (author)

  4. 18-F-FDG PET/CT in Localizing Additional CNS Lesion in a Case of Langerhans Cell Histiocytosis: Determining Accurate Extent of the Disease.

    Science.gov (United States)

    Shamim, Shamim Ahmed; Tripathy, Sarthak; Mukherjee, Anirban; Bal, Chandrasekhar; Tripathi, Madhavi

    2017-01-01

    Central nervous system involvement is a rare manifestation of Langerhans cell histiocytosis (LCH), with bone and skin lesions being more frequent. MR remains the investigation of choice for localizing brain lesions. However, due to poor sensitivity of MRI in detecting osseous and pulmonary lesions, it is not used routinely in staging purposes until and unless indicated. We hereby discuss a case of 6-year-old boy of LCH who was referred for 18-F-FDG PET/CT for staging and knowing the extent of the disease, but a lesion in hypothalamus was picked up incidentally on FDG PET-CT study that was confirmed by MRI.

  5. A single charge in the actin binding domain of fascin can independently tune the linear and non-linear response of an actin bundle network.

    Science.gov (United States)

    Maier, M; Müller, K W; Heussinger, C; Köhler, S; Wall, W A; Bausch, A R; Lieleg, O

    2015-05-01

    Actin binding proteins (ABPs) not only set the structure of actin filament assemblies but also mediate the frequency-dependent viscoelastic moduli of cross-linked and bundled actin networks. Point mutations in the actin binding domain of those ABPs can tune the association and dissociation dynamics of the actin/ABP bond and thus modulate the network mechanics both in the linear and non-linear response regime. We here demonstrate how the exchange of a single charged amino acid in the actin binding domain of the ABP fascin triggers such a modulation of the network rheology. Whereas the overall structure of the bundle networks is conserved, the transition point from strain-hardening to strain-weakening sensitively depends on the cross-linker off-rate and the applied shear rate. Our experimental results are consistent both with numerical simulations of a cross-linked bundle network and a theoretical description of the bundle network mechanics which is based on non-affine bending deformations and force-dependent cross-link dynamics.

  6. 18F-FDG PET/CT in follow-up evaluation in pediatric patients with Langerhans histiocytosis.

    Science.gov (United States)

    Garcia, J R; Riera, E; Bassa, P; Mourelo, S; Soler, M

    We evaluated the impact of 18 F-FDG PET/CT in identifying sites of active disease and to assess therapeutic follow up in a group of pediatric patients with Langerhans cell histiocytosis (LCH). During 2007-2013, 13 18 F-FDG PET/CT studies were performed for follow-up in 7 patients with a diagnosis of LCH (4 female, 3 male; 1-12 years-old). PET findings were analyzed and correlated with the CT and MRI. Findings were also follow-up by these techniques. PET was negative in 4 patients (all diagnosed with bone lesions and one with pituitary involvement also). CT findings showed residual morphological bone lesions in all patients, and hypophysis MRI study showed no abnormal signal. PET remained negative at 10, 14, 25 and 28 months, and no new lesions on CT and MRI were detected. PET was positive in 3 patients (one with cervical lymphadenopathy and 2 with bone lesions, one also with pituitary involvement not identified by PET). CT findings showed pathological cervical lymphadenopathy (n=1), bone lesions (n=2) and also a pituitary MRI lesion (n=1). In a patient with cervical lymphadenopathy histology demonstrated LCH involvement. In the other 2 patients, PET remained positive with an increase of 18 F-FDG bone uptake at 17 and 19 months. In our preliminar study, 18 F-FDG PET is a useful imaging procedure, along with other diagnostic tools, for identification of active lesions. Copyright © 2017 Elsevier España, S.L.U. y SEMNIM. All rights reserved.

  7. {sup 18}F-fluorodeoxyglucose positron emission tomography-computed tomography in the management of adult multisystem Langerhans cell histiocytosis

    Energy Technology Data Exchange (ETDEWEB)

    Obert, Julie [Universite Paris Diderot, Paris (France); Assistance Publique-Hopitaux de Paris, Centre National de Reference de l' Histiocytose Langerhansienne, Service de Pneumologie, Hopital Saint-Louis, Paris (France); Vercellino, Laetitia [Assistance Publique-Hopitaux de Paris, Service de Medecine Nucleaire, Hopital Saint-Louis, Paris (France); Van der Gucht, Axel [Universite Paris Diderot, Paris (France); Assistance Publique-Hopitaux de Paris, Service de Medecine Nucleaire, Hopital Saint-Louis, Paris (France); De Margerie-Mellon, Constance [Universite Paris Diderot, Paris (France); Assistance Publique-Hopitaux de Paris, Service de Radiologie, Hopital Saint-Louis, Paris (France); Bugnet, Emmanuelle; Lorillon, Gwenael [Assistance Publique-Hopitaux de Paris, Centre National de Reference de l' Histiocytose Langerhansienne, Service de Pneumologie, Hopital Saint-Louis, Paris (France); Chevret, Sylvie [Universite Paris Diderot, Paris (France); Assistance Publique-Hopitaux de Paris, Service de Biostatistique et Information Medicale, Hopital Saint-Louis, Paris (France); Biostatistics and Clinical Epidemiology Research Team, U1153 CRESS, Paris (France); Tazi, Abdellatif [Universite Paris Diderot, Paris (France); Assistance Publique-Hopitaux de Paris, Centre National de Reference de l' Histiocytose Langerhansienne, Service de Pneumologie, Hopital Saint-Louis, Paris (France); Biostatistics and Clinical Epidemiology Research Team, U1153 CRESS, Paris (France)

    2017-04-15

    The standard evaluation of multisystem Langerhans cell histiocytosis (LCH) includes a clinical evaluation, laboratory tests and a skeleton/skull X-ray survey, with chest high-resolution computed tomography (HRCT) in the case of pulmonary involvement. Preliminary reports suggest that {sup 18}F-fluorodeoxyglucose positron emission tomography-computed tomography ({sup 18}F-FDG PET-CT) may be useful for evaluating patients with LCH. Fourteen consecutive adult patients with multisystem LCH were included in this retrospective study, and were evaluated using standard procedures and {sup 18}F-FDG PET-CT. The two sets of findings were compared both at baseline and during follow-up. Serial HRCT and pulmonary function tests were used to evaluate outcome in patients with lung involvement. At the baseline evaluation, PET-CT identified every LCH localization found with the standard evaluation (except a mild cecum infiltration). PET-CT showed additional lesions in seven patients, mostly involving bones, and differentiated inactive from active lesions. Thyroid {sup 18}F-FDG uptake was identified in three cases. No pituitary stalk {sup 18}F-FDG uptake was observed in patients with pituitary LCH. Only 3/12 (25 %) patients with pulmonary LCH displayed moderate pulmonary {sup 18}F-FDG uptake. During follow-up, variations (≥50 % of maximum standardized uptake) in bone {sup 18}F-FDG uptake intensity were correlated with disease state and response to treatment. The absence of lung {sup 18}F-FDG uptake did not preclude lung function improvement after treatment. Except for cases with pulmonary and pituitary involvement, {sup 18}F-FDG PET-CT could replace the standard evaluation for staging of adult patients with multisystem LCH. Serial PET-CT scans are useful for evaluating treatment responses, particularly in cases with bone LCH involvement. (orig.)

  8. Contribution to the radiological study of the eosinophilic granuloma of the mandible (Unifocal granuloma due to Langherans' cell histiocytosis)

    International Nuclear Information System (INIS)

    Chigi, Gino; Pastremoli, Alessandro; Pisi, Paolo; Pastremoli, Alfredo

    2005-01-01

    Purpose: The radiological diagnosis of osteolytic lesions of the mandible still constitutes a challenge in some pathological conditions in which the clinical data and the case history are relatively uniform and the radiological picture is lacking in any characteristics. Materials and methods: We reviewed the conventional radiograms of six cases of Langherans' cell histiocytosis (LCH) of the mandible examined over the last ten years. The X-ray examinations were performed in the lateral-oblique projection to allow a view of the horizontal portion of the mandible almost completely free of overlapping images of other bone structures. Results: We identified a series of radiological patterns for these reticulo-endotheliopathies capable of causing granuloma formed by polinuclear eosinophils, plasma cells, lymphocytes, and large mononuclear macrophages with granulopexic and phagocytic activity that proliferate in the bone tissue and can be identified as the Langherans' cells of skin, mucosa, periodontal cavities and bone marrow. The granulomatous tissue penetrates the affected organ elements and, in its spread, it compresses, atrophies, and destroyed the damaged tissue, replacing it. The alterations produced by Langherans' cell histiocytic granuloma are most common in the skeletal system affecting, in order of frequency, the skull, the long bones of the limbs, the foot, the ribs and the spine. The oral mucosa is rarely involved. Conclusions: The radiological investigation of unifocal Langherans' cell histiocytic granuloma of the mandible is essential in the study of perimandibular swelling, although diagnosis is based on biopsy alone. In addition to digital or conventional radiography, other useful examinations are bone scintigraphy, Colour Doppler US, MR and CT, which enables a correct localisation necessary for planning the biopsy and treatment [it

  9. MRI and clinical features of Langerhans cell histiocytosis (LCH) in the pelvis and extremities: can LCH really look like anything?

    International Nuclear Information System (INIS)

    Samet, Jonathan; Weinstein, Joanna; Fayad, Laura M.

    2016-01-01

    To assess clinical and MRI features of Langerhans cell histiocytosis in the pelvis and extremities. The MRI and clinical features of 21 pathologically proven cases of LCH involving the pelvis and extremities were studied. Multiple characteristics of the lesions were evaluated (location, size, T1/ T2/post-contrast features, perilesional bone and soft tissue signal, endosteal scalloping, periosteal reaction, soft tissue mass, pathologic fracture). Pre-biopsy radiologic diagnoses were collected from the original clinical reports. Erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), temperature, and white blood cell count (WBC) were collected at the time of diagnosis when available. The locations of the LCH lesions included five humerus, four femur, five ilium, one tibia, one clavicle, and three scapula. Lesional size ranged from 1.8 to 7.1 cm, with a mean of 3.6 cm. All lesions demonstrated perilesional bone marrow edema, periosteal reaction, endosteal scalloping, and post-contrast enhancement. An associated soft tissue mass was present in 15/21 (71.4 %). Clinically, the WBC, ESR, and CRP were elevated in 2/14 (14 %), 8/12 (67 %), and 4/10 (40 %) of cases, respectively. Fever was documented in 1/15 (7 %) patients and pain was reported in 15/15 (100 %). The clinical and radiologic features of LCH in the pelvis and extremities overlap with infection and malignancy, but LCH must be considered in the differential diagnosis, as it routinely presents with aggressive MRI features, including endosteal scalloping, periosteal reaction, perilesional edema, and a soft tissue mass. Furthermore, an unknown skeletal lesion at presentation without aggressive MRI features is unlikely to represent LCH. (orig.)

  10. MRI and clinical features of Langerhans cell histiocytosis (LCH) in the pelvis and extremities: can LCH really look like anything?

    Energy Technology Data Exchange (ETDEWEB)

    Samet, Jonathan [Northwestern University Feinberg School of Medicine, Department of Medical Imaging, Ann and Robert H. Lurie Children' s Hospital of Chicago, Chicago, IL (United States); Weinstein, Joanna [Northwestern University Feinberg School of Medicine, Departments of Pediatrics, Division of Hematology/Oncology/Stem Cell Transplant, Ann and Robert H. Lurie Children' s Hospital of Chicago, Chicago, IL (United States); Fayad, Laura M. [The Johns Hopkins University School of Medicine, The Russell H. Morgan Department of Radiology and Radiological Science, Baltimore, MD (United States)

    2016-05-15

    To assess clinical and MRI features of Langerhans cell histiocytosis in the pelvis and extremities. The MRI and clinical features of 21 pathologically proven cases of LCH involving the pelvis and extremities were studied. Multiple characteristics of the lesions were evaluated (location, size, T1/ T2/post-contrast features, perilesional bone and soft tissue signal, endosteal scalloping, periosteal reaction, soft tissue mass, pathologic fracture). Pre-biopsy radiologic diagnoses were collected from the original clinical reports. Erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), temperature, and white blood cell count (WBC) were collected at the time of diagnosis when available. The locations of the LCH lesions included five humerus, four femur, five ilium, one tibia, one clavicle, and three scapula. Lesional size ranged from 1.8 to 7.1 cm, with a mean of 3.6 cm. All lesions demonstrated perilesional bone marrow edema, periosteal reaction, endosteal scalloping, and post-contrast enhancement. An associated soft tissue mass was present in 15/21 (71.4 %). Clinically, the WBC, ESR, and CRP were elevated in 2/14 (14 %), 8/12 (67 %), and 4/10 (40 %) of cases, respectively. Fever was documented in 1/15 (7 %) patients and pain was reported in 15/15 (100 %). The clinical and radiologic features of LCH in the pelvis and extremities overlap with infection and malignancy, but LCH must be considered in the differential diagnosis, as it routinely presents with aggressive MRI features, including endosteal scalloping, periosteal reaction, perilesional edema, and a soft tissue mass. Furthermore, an unknown skeletal lesion at presentation without aggressive MRI features is unlikely to represent LCH. (orig.)

  11. Epigenetics: A Fascinating Field with Profound Research, Clinical, & Public Health Implications

    Science.gov (United States)

    Stein, Richard A.; Davis, Devra Lee

    2012-01-01

    Epigenetics is emerging as one of the most dynamic and vibrant biomedical areas. Multiple lines of evidence confirm that inherited genetic changes alone cannot fully explain all phenotypic characteristics of live organisms, and additional factors, which are not encoded in the DNA sequence, are involved. The contribution of non-genetic factors is…

  12. Preliminary study on the evaluation of Langerhans cell histiocytosis using F-18-fluoro-deoxy-glucose PET/CT

    Institute of Scientific and Technical Information of China (English)

    Zhou Wenlan; Wu Hubing; Han Yanjiang; Wang Shaobo; Dong Ye; Wang Quanshi

    2014-01-01

    Background Limited number of studies have been reported regarding the utilization of F-18-fluoro-deoxy-glucose (F-18-FDG) positron emission tomography/computed tomography (F-18-FDG PET/CT) in Langerhans cell histiocytosis (LCH).The aim of this study was to assess the role of F-18-FDG PET/CT in the diagnosis and treatment of LCH.Methods Eight newly diagnosed and seven recurrent patients with LCH received F-18-FDG PET/CT scans.The diagnosis of LCH was established by pathology,multi-modality imaging,and clinical follow-up.Results F-18-FDG PET/CT was positive in 14 patients with 13 true positives and one false positive.All 45 LCH lesions were F-18-FDG avid including six small bone lesions <1.0 cm in diameter.The mean maximal standardized uptake value (SUVmax) was 7.13±4.91.F-18-FDG uptake showed no significant difference between newly diagnosed lesions vs recurrent lesions (SUVmax:6.50±2.97 vs.7.93±6.60,t=-0.901,P=0.376).Among 45 LCH lesions,68.9% (31/45) were found in bones and 31.1% (14/45) in soft tissue.The most commonly involved bones were the pelvis and vertebrae.There was no significant difference in F-18-FDG uptake between bone lesions vs.non-bone lesions (SUVmax:6.30±2.87 vs.8.97±7.58,t=1.277,P=0.221).In two patients,changes in F-18-FDG uptake on serial PET/CT scans reflected response of lesions to treatment.Conclusions The present study suggests that F-18-FDG PET/CT may be useful for diagnosis and assessing the treatment response of LCH.Because of the small sample size,further research is warranted to confirm our findings.

  13. Successful treatment with cladribine of Erdheim-Chester disease with orbital and central nervous system involvement developing after treatment of langerhans cell histiocytosis

    Directory of Open Access Journals (Sweden)

    Perić Predrag

    2016-01-01

    Full Text Available Introduction. Erdheim-Chester disease (ECD is a rare, systemic form of non-Langerhans cell histiocytosis of the juvenile xantho-granuloma family with characteristic bilateral symmetrical long bone osteosclerosis, associated with xanthogranulomatous extras-keletal organ involvement. In ECD, central nervous system (CNS and orbital lesions are frequent, and more than half of ECD patients carry the V600E mutation of the proto-oncogene BRAF. The synchronous or metachronous development of ECD and Langerhans cell histiocytosis (LCH in the same patients is rare, and the possible connection between them is still obscure. Cladribine is a purine substrate analogue that is toxic to lymphocytes and monocytes with good hematoencephalic penetration. Case report. We presented a 23-year-old man successfully treated with cladribine due to BRAF V600E-mutation-negative ECD with bilateral orbital and CNS involvement. ECD developed metachronously, 6 years after chemotherapy for multisystem LCH with complete disease remission and remaining central diabetes insipidus. During ECD treatment, the patient received 5 single-agent chemotherapy courses of cladribine (5 mg/m2 for 5 consecutive days every 4 weeks, with a reduction in dose to 4 mg/m2 in a fifth course, delayed due to severe neutropenia and thoracic dermatomal herpes zoster infection following the fourth course. Radiologic signs of systemic and CNS disease started to resolve 3 months after the end of chemotherapy, and CNS lesions completely resolved within 2 years after the treatment. After 12-year follow-up, there was no recurrence or appearance of new systemic or CNS xanthogranu-lomatous lesions or second malignancies. Conclusion. In accordance with our findings and recommendations provided by other authors, cladribine can be considered an effective alternative treatment for ECD, especially with CNS involvement and BRAF V600E-mutation-negative status, when interferon-α as the first-line therapy fails.

  14. Evolutionary dynamics of mammalian karyotypes

    Directory of Open Access Journals (Sweden)

    Carlo Alberto Redi

    2012-12-01

    Full Text Available This special volume of Cytogenetic and Genome Research (edited by Roscoe Stanyon, University of Florence and Alexander Graphodatsky, Siberian division of the Russian Academy of Sciences is dedicated to the fascinating long search of the forces behind the evolutionary dynamics of mammalian karyotypes, revealed after the hypotonic miracle of the 1950s....

  15. Steroids: A Timeless Fascination

    Indian Academy of Sciences (India)

    the brain and spinal cord. It is also present in animal fats or oils. HO ... The percentage composition and size of LDL and HDL are given in Table 1. ... 7-10. 50. 30. Lipoproteins are large assemblies of lipids in association with proteins. The two.

  16. Fascination at high pressures

    International Nuclear Information System (INIS)

    Chidambaram, R.

    1992-01-01

    Research at high pressures has developed into an interdisciplinary area which has important implications for and applications in the areas of physics, chemistry, materials sciences, planetary sciences, biology, engineering sciences and technology. The state of-the-art in this field is reviewed and future directions are indicated. (M.G.B.)

  17. Fascinating Organic Transformations

    Indian Academy of Sciences (India)

    Definition of a Hydrogen Bond. A hydrogen atom bonded to an electronegative atom like oxygen or nitrogen has a small positive charge, due to bond polarization. ... government assistance). "Vidyanantha Education. Centre", to promote education, art and culture. Hydrogen bonds are. Ubiquitous, easily recognisable and.

  18. Those fascinating numbers

    CERN Document Server

    Koninck, Jean-Marie De

    2009-01-01

    Who would have thought that listing the positive integers along with their most remarkable properties could end up being such an engaging and stimulating adventure? The author uses this approach to explore elementary and advanced topics in classical number theory. A large variety of numbers are contemplated: Fermat numbers, Mersenne primes, powerful numbers, sublime numbers, Wieferich primes, insolite numbers, Sastry numbers, voracious numbers, to name only a few. The author also presents short proofs of miscellaneous results and constantly challenges the reader with a variety of old and new n

  19. Dynamics at the nanoscale

    International Nuclear Information System (INIS)

    Stoneham, A.M.; Gavartin, J.L.

    2007-01-01

    However fascinating structures may be at the nanoscale, time-dependent behaviour at the nanoscale has far greater importance. Some of the dynamics is random, with fluctuations controlling rate processes and making thermal ratchets possible. Some of the dynamics causes the transfer of energy, of signals, or of charge. Such transfers are especially efficiently controlled in biological systems. Other dynamical processes occur when we wish to control the nanoscale, e.g., to avoid local failures of gate dielectrics, or to manipulate structures by electronic excitation, to use spin manipulation in quantum information processing. Our prime purpose is to make clear the enormous range and variety of time-dependent nanoscale phenomena

  20. 18F-fluorodeoxyglucose positron emission tomography/computed tomography for primary thyroid langerhans histiocytosis: A case report and literature review

    International Nuclear Information System (INIS)

    Long, Qi; Shaoyan, Wang; Hui, Wang

    2015-01-01

    Langerhans cell histiocytosis (LCH) is a rare clonal proliferative disease, with an incidence rate of 4.0–5.4/1 million individuals. LCH encompasses a spectrum of disorders with diverse clinical presentations ranging from a single organ to multiple organ involvement. LCH rarely involves the thyroid gland. We presented a case with LCH of thyroid gland. The patient had painless progressive neck enlargement and then diabetes insipidus. Ultrasonic scan and magnetic resonance imaging scan revealed nodular goiter and pituitary stalk enlargement, respectively. Histopathological analysis revealed features of histiocytoid cells. 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) was performed in order to rule out the presence of whole body infiltration. 18F-FDG PET/CT also demonstrated increased uptake in the thickening pituitary stalk and maxillofacial skin lesion, in addition to the bilateral thyroid nodules, CT showed the left lung nodule and the skull destruction without 18F-FDG uptake. This report emphasizes the role of 18F-FDG PET/CT in multiple organs involvement of patients with LCH

  1. Histiocitose das células de Langerhans na região anogenital Langerhans cell histiocytosis of the anogenital region

    Directory of Open Access Journals (Sweden)

    M. S. Neto

    1998-12-01

    Full Text Available A Histiocitose das células de Langerhans (HCL acometendo o trato genital tem uma incidência rara com apenas 48 casos relatados na literatura1-5 . Considerando somente as lesões da região anogenital, esse número cai para dois casos descritos1,2. Reportamos o 3º caso de HCL anogenital em uma paciente de 31 anos, branca, cuja comprovação diagnóstica foi feita através de microscopia eletrônica. O tratamento realizado foi quimioterapia sistêmica e excisão cirúrgica local.The Langerhans cell histiocytosis (LCH of the genital tract is rare, with only 48 cases related in the literature1-5. There were reported only 2 cases in the anogenital region1,2. We reported the third case of LCH in the anogenital region; patient was female, 31 years-old, caucasian and the diagnosis was confirmed by electron microscopic magnification. The treatment was local surgical excision and systemic chemotherapy.

  2. Langerhans cell histiocytosis of the urinary bladder in a patient with bladder cancer previously treated with intravesical Bacillus Calmette-Guérin therapy.

    Science.gov (United States)

    Numakura, Satoe; Morikawa, Teppei; Ushiku, Tetsuo; Toyoshima, Toyoaki; Fukayama, Masashi

    2014-02-01

    We report an extremely rare case of Langerhans cell histiocytosis (LCH) of the urinary bladder. A 68-year-old man presented with gross hematuria. Cystoscopy showed multiple papillary tumors in the urinary bladder, and transurethral resection was performed. Pathological diagnosis was high-grade papillary urothelial carcinoma with lamina propria invasion. The patient received six treatments with intravesical Bacillus Calmette-Guérin (BCG) therapy. Seven months after surgery, follow-up cystoscopy showed three elevated lesions in the urinary bladder, two of which were identified histologically as recurrent urothelial carcinoma. Microscopic examination of the lesion at the anterior wall revealed diffuse infiltration of medium to large histiocytoid cells in the lamina propria, many of which had distorted nuclei and nuclear grooves. Dense eosinophilic infiltration was also observed. Immunohistochemically, the histiocytoid cells were diffusely positive for S-100 and CD1a, but negative for cytokeratin AE1/AE3 and melanosome-associated antigen recognized by HMB-45. Based on the histological and immunohistochemical features, we diagnosed the lesion as LCH of the urinary bladder. There was no evidence of recurrence of either bladder cancer or LCH after an 18-month follow-up. To avoid misdiagnosis, urologists and pathologists should be aware that LCH may develop in the urinary bladder after intravesical BCG therapy for bladder cancer. Copyright © 2013 Elsevier GmbH. All rights reserved.

  3. Pulmonary Langerhans cell histiocytosis with cervical lymph node involvement, and coexistence with pulmonary tuberculosis and right pneumothorax: a case report and review of literature.

    Science.gov (United States)

    Gao, Limin; Li, Huifang; Li, Gandi; Liu, Weiping; Li, Jinnan; Zhang, Wenyan

    2015-01-01

    We report an uncommon 22-year-old male Pulmonary Langerhans Cell Histiocytosis (PLCH) case which co-existed with pulmonary tuberculosis (TB). Unlike the common PLCH cases, this PLCH case has cervical lymph node involvement and right pneumothorax. The diagnosis was established by the imaging of lung and the biopsies of the lung and left neck lymph node. Imaging of the chest showed characteristic small nodules and thin-walled cysts and right pneumothorax. The LCH cells in the lung and left neck lymph node were characterized by large convoluted nuclei with cerebriform indentations of the nuclear envelope and longitudinal grooves. The nuclei contained small eosinophilic nucleoli and moderate amount cytoplasm. Immunohistochemically, the histiocytoid cells were positive for Langerin, CD1a and S-100. Acid-fast bacilli were found in sputum and lung biopsy tissue. To the best of our knowledge, this is the first case of PLCH with cervical lymph node involvement, and coexisted with pulmonary tuberculosis, right pneumothorax. A contribution of this case and review three of the five cases of PLCH with extrapulmonary involvement to lymph nodes resolved spontaneously after smoking cessation constitute a novel addition that it is inappropriate to regard pulmonary/nodal LCH as multi-organ or disseminated disease, and the treatment methods are the same whether the PLCH patient with lymph node involvement or not.

  4. Dynamics

    CERN Document Server

    Goodman, Lawrence E

    2001-01-01

    Beginning text presents complete theoretical treatment of mechanical model systems and deals with technological applications. Topics include introduction to calculus of vectors, particle motion, dynamics of particle systems and plane rigid bodies, technical applications in plane motions, theory of mechanical vibrations, and more. Exercises and answers appear in each chapter.

  5. 111In-Octreotide and 99mTc-MDP scintigraphy in the detection of bone lesions in Langerhans cell histiocytosis

    International Nuclear Information System (INIS)

    Hervas, I.; Bello, P.; Gonzalez-Cabezas, P.; Flores, D.; Perez-Velasco, R.; Torres, I.; Castel, V.; Mateo, A.; Canete, A.

    2002-01-01

    Aim: Langerhans cell histiocytosis (LCH) is a granulomatous disease which can involve multiples sites of the body. Diagnostic imaging is of utmost importance in the management of these patients. Since now radiographic skeletal survey and bone scintigraphy (BS) have been used to assess bone involvement (both with low specificity). Magnetic resonance and CT have been used to assess visceral involvement but with the limitation that can not give information about the functional status. Recently two groups of investigators (Lastoria et al. and Calming et al.) have proposed somatostatin receptor scintigraphy (SSRS) to detect active lesions and for monitoring the response to treatment, due to the somatostatin analogue octreotide binds to the cell membrane of activated lymphocytes expressing somatostatine receptors. The aim of this study is to assess bone and somatostatine receptor scintigraphy in the detection of bone involvement in LCH in children. Visceral involvement has not been assessed due to none of the patients presented it at the moment of the SRS. Methods: 17 scintigraphies (11 SSRS and 6 BS) were performed in seven patients (3 girls and 4 boys) aged at diagnosis: 18 month- 12 years (mean age 6,2 years). The findings obtained in the scintigraphies were compared with clinical evolution and other imaging techniques. Results: All the BS detected the diagnosed lesions, that decreased the uptake after the treatment. In three cases BS detected one unknown bone lesion. Two SSRS could not detect a lesion on right rib in two patients, both at the moment of diagnosis. SSRS was true negative in one patient (clinical and other imaging remission) and true positive in the other four cases. SSRS detected three new unknown bone lesions. SRSS showed decreased uptake after treatment and increased uptake in the relapses. Conclusions: Somatostatin receptor and Bone scintigraphy can be used to detect active LCH bone lesions in children and can help in monitoring the response to

  6. Diagnósticos diferenciales de la histiocitosis a células de Langerhans The differential diagnostics of Langerhans cell histiocytosis

    Directory of Open Access Journals (Sweden)

    C. N. Chirino

    2007-06-01

    Full Text Available La histiocitosis a células de Langerhans (HCL debe diferenciarse de las siguientes entidades: eritema tóxico neonatorum (ETN, dermatitis seborreica (DS, foliculitis pustulosa eosinofílica (FPE, incontinencia pigmenti (IP, mastocitosis/urticaria pigmentosa (M/UP, acrodermatitis enteropática (ADE, síndrome de Wiskott-Aldrich (WAS, acropustulosis infantil (API. Además se deben considerar la enfermedad de Rosai- Dorfman (ERD, xantomas diseminados, melanosis pustulosa neonatal (MPN, candidiasis congénita, listeriosis neonatal, herpes simple perinatal y la varicela neonatal. Debido a que los métodos auxiliares de laboratorio no siempre están disponibles o los resultados laboratoriales algunas veces son extemporáneos, y puesto que el médico práctico a menudo necesita tomar decisiones precozmente, es que la epidemiología resulta útil, pues brinda el marco adecuado para ordenar y jerarquizar las sospechas diagnósticas frente a un caso concreto, con un paciente determinado, en un momento específico.The differential diagnostics of Langerhans cell histiocytosis should include the following disorders: erythema toxicum neonatorum, seborrheic dermatitis, eosinophilic pustular folliculitis, incontinentia pigmenti, mastocytosis / urticaria pigmentosa, acrodermatitis enteropathica, Wiskott-Aldrich syndrome, infantile acropustulosis, Rosai- Dorfman disease, xanthoma disseminatum, neonatal pustular melanosis, congenital candidiasis, perinatal listeriosis, perinatal herpes simplex, neonatal varicella. Since the auxiliary methods of lab are not always available, or lab results are sometimes extemporaneous, the physicians often needs to make quick decisions. The epidemiology is useful because it offers the appropriate mark to prioritize the diagnostic in specific cases

  7. Histiocitose das células de Langerhans: experiência de 16 anos Langerhans cell histiocytosis: a 16-year experience

    Directory of Open Access Journals (Sweden)

    Márcia Kanadani Campos

    2007-02-01

    Full Text Available OBJETIVOS: Descrever a apresentação clínica da histiocitose das células de Langerhans e comparar sua evolução de acordo com a idade, estadiamento e resposta ao tratamento. MÉTODOS: Análise retrospectiva dos dados referentes a 33 crianças com histiocitose das células de Langerhans acompanhadas no Hospital das Clínicas da Universidade Federal de Minas Gerais no período de 1988 a 2004. RESULTADOS: A idade ao diagnóstico variou de 2 meses a 16 anos (mediana: 2,5 anos. Dezessete crianças eram do sexo masculino. O tempo de seguimento variou de 21 dias a 16,2 anos (mediana: 3,4 anos. As manifestações clínicas mais comuns ao diagnóstico foram lesões osteolíticas, linfadenomegalia e lesões cutâneas. A sobrevida global para todo o grupo foi de 86,1% aos 16 anos (IC95% 66,6-94,6. Os óbitos ocorreram em pacientes com doença multissistêmica e disfunção orgânica ao diagnóstico. Os pacientes que apresentaram resposta "melhor" à sexta semana de tratamento apresentaram uma probabilidade estimada de sobrevida global significativamente maior em relação aos que apresentaram progressão da doença. A sobrevida global foi significativamente maior para os pacientes com doença em um único sistema. A probabilidade de sobrevida livre de eventos para todo o grupo foi de 30,9% aos 16 anos (IC95% 15,6-47,5, sendo significativamente maior para os portadores de doença em um único sistema. A idade não se associou com a sobrevida livre de eventos. A seqüela mais comum foi o diabetes insipidus. Não foram observados casos de neoplasias secundárias. CONCLUSÃO: A histiocitose das células de Langerhans apresenta uma grande variedade de manifestações clínicas, com alta taxa de recidivas e baixa taxa de mortalidade.OBJECTIVES: To describe the clinical course of Langerhans cell histiocytosis and to compare its outcome according to age, staging of the disease and treatment response. METHODS: Retrospective analysis of data on 33 children with

  8. Fascinating physics. An illustrated expedition from the universe until the world of the elementary particles; Faszinierende Physik. Ein bebildeter Streifzug vom Universum bis in die Welt der Elementarteilchen

    Energy Technology Data Exchange (ETDEWEB)

    Bahr, Benjamin [Albert-Einstein-Institut (Max-Planck Institut fuer Gravitationsphysik), Golm (Germany); Riebe, Kristin [Potsdam Univ. (Germany). Leibniz-Institut fuer Astrophysik; Resag, Joerg

    2013-07-01

    ''Fascinating physics'' is a picturesque expedition through 140 themes of classical and modern physics. On each one double-page to the reader is thereby offered a compact access in each one theme: From the aurora until the black hole, from the particle accelerator until the GPS system, from the curved space-time until the supersymmetry, from the oscillating dipole until Foucault's pendulum - a large variety of themes is taken up and carefully explained. Thereby the special strength of the book lies in the clear language and the explanations get along mostly without formulas - accompanied by breathtaking pictures, which lead the beauty of our world in front of the eyes.

  9. Histiocitosis de células de Langerhans localizada en hueso malar: Presentación de un caso Localized langerhans cell histiocytosis of the zygomatic bone: A case report

    Directory of Open Access Journals (Sweden)

    María Loreto Castellón Zirpel

    2011-09-01

    Full Text Available La histiocitosis de células de Langerhans localizada (HCLL, conocida como granuloma eosinófilo, representa entre el 50 y el 60% de todos los casos de histiocitosis de células de Langerhans. El tratamiento clásico para la HCLL ha sido el curetaje o la resección de las lesiones óseas. Hay publicaciones de casos tratados con inyección intralesional de corticosteroides, combinado con curetaje. Se presenta un caso clínico de un paciente de tres años de edad con diagnóstico de HCLL que compromete en su extensión el hueso malar, tratado con infiltraciones de corticosteroides y posterior curetaje de la lesión. A un año de realizado el tratamiento, el paciente se encuentra asintomático y con una regeneración ósea del hueso malar, evidenciable en la tomografía axial computarizada.Localized Langerhans cell histiocytosis (LLCH, also known as eosinophilic granuloma, represents 50 to 60% of all cases of Langerhans cell histiocytosis. The standard treatment for LLCH has been lesion curettage or resection. Cases treated with intralesional corticosteroid injections combined with curettage have been described. We report the case of a three-year-old patient diagnosed of LLCH with extensive zygomatic bone involvement, who was treated with corticosteroid infiltrations and subsequent curettage of the lesion. One year after treatment, the patient is asymptomatic with zygomatic reossification evidenced on computed tomography.

  10. The fascinating early history of optics! Archaeological optics 2009: our knowledge of the early history of lenses, mirrors, and artificial eyes!

    Science.gov (United States)

    Enoch, Jay M.

    2009-08-01

    The early history of optics and vision science (older term: physiological optics) is indeed fascinating. The earliest known true lenses have been found in "eyes" of Egyptian statues which contain superb, complex, and well-polished eye-lens units. The oldest ones known are dated circa 2575 BCE = BC, Dynasty IV, Old Kingdom. These eye-lens units induce a fascinating and powerful visual illusion, but they are just too good to have been the first lenses, or even the first lenses of this design! So saying, no earlier dateable lenses have been found in Egypt or elsewhere. Recently, at the Boston Museum of Fine Arts, the writer noted a previously undetected lens in this series (a first in the Western Hemisphere). Oddly, dateable simpler magnifying lenses and burning glasses seem to have appeared later in time (?)! Manufactured mirrors are quite a bit older, dating from circa 6000 BCE in atal Hyk, located in south-central modern-day Turkey. Using these ancient mirrors, the image quality obtained is remarkable! Recently discovered ancient artificial eyes, located, in situ, in exhumed corpses, have been dated circa 3000 BCE (one discovered in Iran) 5000 BCE (one found in Spain). On the 3000 BCE artificial eye, there are drawn light rays (the writer believes these to be the oldest known depiction of light rays!) spreading out from (or passing into) the iris/ pupil border! Added interesting aspects associated with the early development of light-rays are considered. Thus, early optics can be readily traced back to the Neolithic era (the new stone age), and in some cases before that time period. We have deep roots indeed!

  11. Atomic energy law after the opt-out. Alive and fascinating. Report about the 14th German atomic energy law symposium 2012

    International Nuclear Information System (INIS)

    Leidinger, Tobias

    2013-01-01

    Atomic energy law remains a living, fascinating subject matter. Nearly 200 participants were convinced of this impression at the 14 th German Atomic Energy Law Symposium held in Berlin on November 19-20, 2012. Under the scientific chairmanship of Professor Dr. Martin Burgi, Ludwig Maximilian University of Munich, the German Federal Ministry for the Environment, Nature Conservation and Nuclear Safety (BMU), after an interruption of 5 years, again organized a scientific conference about practice-related topics of atomic energy and radiation protection law. Atomic energy law once again proved to be a reference area for sophisticated issues of constitutional law and administrative law above and beyond its technical confines. The agenda of the 14 th German Atomic Energy Law Symposium featured a broad spectrum of topics ranging from backfitting of nuclear power plants to European atomic energy and radiation protection law, to challenges facing national legal systems in the execution of atomic energy law, to legal issues connected with decommissioning and waste management, and on to the topical subject of finding a repository site. The 14 th German Atomic Energy Law Symposium, on the whole, again demonstrated that an open discourse between science and practice is able to furnish important contributions to the implementation of laws in a balanced way rooted in practice. Especially the contributions dealing with the independence of public authorities and their organization, the doctrine of the reservation of functions of the executive branch, and planning by laws contain additional provisions able to influence the continued development of administrative law also above and beyond atomic energy law. The BMU also referred to a decision just heard from Brussels to the effect that a new European Safety Directive would be published as early as in 2013. As a consequence of the nuclear stress tests conducted EU-wide, the Directive is to lay down provisions about transparency

  12. miR-145-dependent targeting of junctional adhesion molecule A and modulation of fascin expression are associated with reduced breast cancer cell motility and invasiveness.

    Science.gov (United States)

    Götte, M; Mohr, C; Koo, C-Y; Stock, C; Vaske, A-K; Viola, M; Ibrahim, S A; Peddibhotla, S; Teng, Y H-F; Low, J-Y; Ebnet, K; Kiesel, L; Yip, G W

    2010-12-16

    Micro RNAs are small non-coding RNAs, which regulate fundamental cellular and developmental processes at the transcriptional and translational level. In breast cancer, miR-145 expression is downregulated compared with healthy control tissue. As several predicted targets of miR-145 potentially regulate cell motility, we aimed at investigating a potential role for miR-145 in breast cancer cell motility and invasiveness. Assisted by Affymetrix array technology, we demonstrate that overexpression of miR-145 in MDA-MB-231, MCF-7, MDA-MB-468 and SK-BR-3 breast cancer cells and in Ishikawa endometrial carcinoma cells leads to a downregulation of the cell-cell adhesion protein JAM-A and of the actin bundling protein fascin. Moreover, podocalyxin and Serpin E1 mRNA levels were downregulated, and gamma-actin, transgelin and MYL9 were upregulated upon miR-145 overexpression. These miR-145-dependent expression changes drastically decreased cancer cell motility, as revealed by time-lapse video microscopy, scratch wound closure assays and matrigel invasion assays. Immunofluorescence microscopy demonstrated restructuring of the actin cytoskeleton and a change in cell morphology by miR-145 overexpression, resulting in a more cortical actin distribution, and reduced actin stress fiber and filopodia formation. Nuclear rotation was observed in 10% of the pre-miR-145 transfected MDA-MB-231 cells, accompanied by a reduction of perinuclear actin. Luciferase activation assays confirmed direct miR-145-dependent regulation of the 3'UTR of JAM-A, whereas siRNA-mediated knockdown of JAM-A expression resulted in decreased motility and invasiveness of MDA-MB-231 and MCF-7 breast cancer cells. Our data identify JAM-A and fascin as novel targets of miR-145, firmly establishing a role for miR-145 in modulating breast cancer cell motility. Our data provide a rationale for future miR-145-targeted approaches of antimetastatic cancer therapy.

  13. Fascinating Organic Molecules from Nature

    Indian Academy of Sciences (India)

    IAS Admin

    santalin A and santalin B , could be obtained in the pure state. In .... common to the warmer regions of Asia. ... Islands off the North West coast of Africa brought back to Europe ... it is a very popular tree in many of the Pacific Islands, including.

  14. Fascinating Organic Molecules from Nature

    Indian Academy of Sciences (India)

    IAS Admin

    Mundulea and Millettia belonging to the family Fabaceae. Different parts of these plants, ... metabolites known as the rotenoids, the parent member of which is rotenone(1). .... dride gives a single product in high yield. The IR spectrum of the.

  15. Frederik Ruysch's Fascination With Urolithiasis

    Science.gov (United States)

    Moran, Michael E.; Ruzhansky, Katherine

    2008-09-01

    Frederik Ruysch was born on March 23, 1638, in The Hague, and studied at the University of Leiden, where he graduated in 1664. He married a daughter of a famous architect and became a praelector of the Amsterdam surgeon's guild in 1665. In 1666, his rise continued, as he became elected as the Professor of the Anthenaeum Illustre. In 1668, Ruysch became the chief instructor to the midwives and by 1679 was the forensics advisor to Amsterdam's courts. His anatomical knowledge was second to none, and he gained worldwide notoriety for his discovery of the valves in lymphatics and the vomeronasal organ. Ruysch was keenly interested in dissection and anatomy, and developed his own methods for preservation of specimens. His secret was called liquor balsamicum. Over 300 years ago, Ruysch developed all of his talents to the point of creating a menagerie, of sorts, out of his specimens. The popularity of his rather morbid exhibits attracted such dignitaries as Peter The Great in 1697. Ruysch had several children from his marriage, and his daughter Rachel helped him illustrate many of his collections. Frederik Ruysch became an intriguing historical figure, worthy of some attention at kidney stone meetings, precisely because he chose these concretions to serve as one of the "finishing elements" in several of his collections. The purpose of this presentation is to present to a knowledgeable stone group, the artistic license of one of the first entrepreneurial surgeons and anatomists of the 17th century. Ruysch was a skilled surgeon, obstetrician, and anatomist, keenly interested in the science of anatomy, especially infant and fetal anatomy. In addition, he exhibited his fine collection of urinary stones in a rather unique way, in his "anatomical pieces."

  16. Fascinating Organic Molecules from Nature

    Indian Academy of Sciences (India)

    IAS Admin

    dise, species of which are found in New Guinea, have been hunted from ancient ... for the production of healthy progeny. Previous articles: 1. .... green colours. The pig- ments responsible for these colours are known as psittacofulvins4, which.

  17. Graphene and its fascinating attributes

    CERN Document Server

    Enoki, Toshiaki; Rao, C N R

    2011-01-01

    Graphene, a single sheet of graphite, has an unconventional electronic structure that can be described in terms of massless Dirac Fermions. This interesting electronic feature is not only an important fundamental issue in condensed matter physics but also

  18. Fascinating Organic Molecules from Nature

    Indian Academy of Sciences (India)

    psittacofulvins); porphyrins and pterins. Author Affiliations. N R Krishnaswamy1 C N Sundaresan2. No.12, 9th Main Road, Banashankari 2nd Stage, Bangalore 560 070, India. Department of Chemistry Sri Sathya Sai Institute of Higher Learning ...

  19. Fascinating Rhythms Played on Fingertips

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Zhao Cong, a young pipa (four-stringedChinese lute) performer with the China CentralTraditional Music Ensemble, was born into a familyof musicians. She developed an extraordinaryinterest in this ancient Chinese instrument in herchildhood. When her parents asked 7-year-old

  20. Fascinating World of Shock Waves

    Indian Academy of Sciences (India)

    Srimath

    travelling at supersonic speeds (more than the sound speed at ... actual earth- quake, travel at supersonic speeds. .... The time scale of the shock wave is also important ..... real lithotripsy where a shock wave is used shatter the kidney stones!

  1. Fascinating Organic Molecules from Nature

    Indian Academy of Sciences (India)

    Keywords. Pigments of red sandalwood; Safflower; chica red; Brazil wood; Dragon's blood; Miro wood and Kamala dye. Author Affiliations. N R Krishnaswamy1 C N Sundaresan2. No.12, 9th Main Road Banashankari 2nd Stage Bangalore 560 070, India. Department of Chemistry Sri Sathya Sai Institute of Higher Learning ...

  2. A toddler with hair fascination.

    Science.gov (United States)

    Kao, Patricia; Needlman, Robert D; Stein, Martin T

    2010-04-01

    Joseph is a 24-months old boy referred by his pediatrician because of an "obsession" with pulling and eating hair. When Joseph was 14 months old, he enjoyed touching and twirling his mother's long hair. She observed that it seemed to provide comfort to him. At 18 months, he initiated pulling out and eating his own hair, twirling his mother's hair around his thumb and then sucking on it. Currently, he searches the carpet or a hard floor and looks for hair to eat. The identical behavior is observed at daycare. Joseph's teacher commented, "He pulled hair from a girl who has the longest hair of all the children. We try to distract him from this habit, but he is not distracted for long." Less frequently, Joseph has also eaten sand, chalk, and crayons at daycare. Joseph's mother describes him as a "happy and outgoing" child who interacts with his peers and has a best friend at the daycare. There have not been recent changes or stressful events in his life. Joseph separates from his mother with ease and he sleeps comfortably through the night in his own bed. There have been no episodes of nausea, vomiting, abdominal pain, or constipation. Strands of hair are occasionally seen in the stool. Prenatal and perinatal history was unremarkable. Joseph was breast-fed for 11 months, described as an "easy" baby, achieved motor, social, and language developmental milestones at the usual time, and has been in excellent health. He lives with his mother and maternal grandparents; the biological father has never been involved in his care. At 20 months, Joseph's pediatrician suggested cutting his hair. After several haircuts, Joseph stopped pulling his own hair. However, he continued to search the floor for hair. Hemoglobin and a blood lead level were normal. Joseph appeared pleasant and friendly with normal growth parameters and facial features. He was sitting comfortably on his mother's lap, sucking on his thumb. Social interactions with his mother were appropriate and reciprocal. He warmed up quickly to the examiner and engaged in play. He spoke in two to three word sentences and responded to questions with a speech pattern that was 50% intelligible. Physical and developmental examinations were normal. At the end of the examination, Joseph searched his mother's purse and located a piece of hair. He twirled the hair around his thumb and sucked on it. Initially, he refused to remove his thumb from his mouth. With gentle persuasion, he eventually removed his thumb and agreed to throw the hair in the trash. He did not appear distressed.

  3. Bimetallic Ag-Pd nanoparticles-decorated graphene oxide: a fascinating three-dimensional nanohybrid as an efficient electrochemical sensing platform for vanillin determination

    International Nuclear Information System (INIS)

    Li, Junhua; Feng, Haibo; Li, Jun; Jiang, Jianbo; Feng, Yonglan; He, Lingzhi; Qian, Dong

    2015-01-01

    Highlights: • A 3D Ag-Pd/GO nanohybrid was fabricated via a green and in situ chemical route. • Ag-Pd/GO shows excellent electro-catalytic properties for the oxidation of vanillin. • The 3D hybrid-based sensor shows excellent performances for the vanillin detection. • This proposed method was successfully used to detect vanillin in children’s snacks. - Abstract: In this work, a fascinating hybrid based on Ag-Pd bimetallic nanoparticles-decorated graphene oxide (Ag-Pd/GO) has been successfully synthesized by a green and in situ chemical reduction strategy. The resultant hybrid was particularly characterized by scanning electron microscopy, transmission electron microscopy, energy dispersive X-ray spectroscopy, ultraviolet-visible spectroscopy and electrochemical techniques. The morphological results illustrate that Ag-Pd nanoparticles in microspheric appearances are highly dispersed and embedded on the GO layers, resulting in a rough surface and three-dimensional (3D) microstructure with a high Ag-Pd content in the matrix. The as-synthesized 3D Ag-Pd/GO hybrid displays distinctly enhanced electrocatalytic activity for the vanillin oxidation in comparison with that of the monometal-decorated GO, revealing a synergistic effect of the matrix GO and the doped bimetallic Ag-Pd. Therefore, the Ag-Pd/GO composite can be used as an enhanced electrochemical sensing platform for the sensitive determination of vanillin, and the fabricated sensor displays a wide detection range of 0.02–45 μmol dm −3 , low detection limit of 5 nmol dm −3 and satisfactory recoveries between 98.8 % and 103.5 %. All the results demonstrate that the 3D hybrids integrated graphene with bimetallic nanoparticles are promising candidates for the development of high-performance electrochemical sensors

  4. Evolutionary dynamics of complex communications networks

    CERN Document Server

    Karyotis, Vasileios; Papavassiliou, Symeon

    2013-01-01

    Until recently, most network design techniques employed a bottom-up approach with lower protocol layer mechanisms affecting the development of higher ones. This approach, however, has not yielded fascinating results in the case of wireless distributed networks. Addressing the emerging aspects of modern network analysis and design, Evolutionary Dynamics of Complex Communications Networks introduces and develops a top-bottom approach where elements of the higher layer can be exploited in modifying the lowest physical topology-closing the network design loop in an evolutionary fashion similar to

  5. An exploration of dynamical systems and chaos

    CERN Document Server

    Argyris, John H; Haase, Maria; Friedrich, Rudolf

    2015-01-01

    This book is conceived as a comprehensive and detailed text-book on non-linear dynamical systems with particular emphasis on the exploration of chaotic phenomena. The self-contained introductory presentation is addressed both to those who wish to study the physics of chaotic systems and non-linear dynamics intensively as well as those who are curious to learn more about the fascinating world of chaotic phenomena. Basic concepts like Poincaré section, iterated mappings, Hamiltonian chaos and KAM theory, strange attractors, fractal dimensions, Lyapunov exponents, bifurcation theory, self-similarity and renormalisation and transitions to chaos are thoroughly explained. To facilitate comprehension, mathematical concepts and tools are introduced in short sub-sections. The text is supported by numerous computer experiments and a multitude of graphical illustrations and colour plates emphasising the geometrical and topological characteristics of the underlying dynamics. This volume is a completely revised and enlar...

  6. Contribution to the radiological study of the eosinophilic granuloma of the mandible (Unifocal granuloma due to Langherans' cell histiocytosis); Contributo allo studio radiologico del granuloma eosinofilo della mandibola (granuloma unifocale da istiocitosi delle cellule di Lagherhans)

    Energy Technology Data Exchange (ETDEWEB)

    Chigi, Gino; Pastremoli, Alessandro; Pisi, Paolo; Pastremoli, Alfredo [Bologna Univ., Bologna (Italy). Dipartimento di scienze odontomastologiche; Bianchi, Giuseppe [Istituti Ortopedici Rizzoli, Bologna (Italy)

    2005-04-01

    Purpose: The radiological diagnosis of osteolytic lesions of the mandible still constitutes a challenge in some pathological conditions in which the clinical data and the case history are relatively uniform and the radiological picture is lacking in any characteristics. Materials and methods: We reviewed the conventional radiograms of six cases of Langherans' cell histiocytosis (LCH) of the mandible examined over the last ten years. The X-ray examinations were performed in the lateral-oblique projection to allow a view of the horizontal portion of the mandible almost completely free of overlapping images of other bone structures. Results: We identified a series of radiological patterns for these reticulo-endotheliopathies capable of causing granuloma formed by polinuclear eosinophils, plasma cells, lymphocytes, and large mononuclear macrophages with granulopexic and phagocytic activity that proliferate in the bone tissue and can be identified as the Langherans' cells of skin, mucosa, periodontal cavities and bone marrow. The granulomatous tissue penetrates the affected organ elements and, in its spread, it compresses, atrophies, and destroyed the damaged tissue, replacing it. The alterations produced by Langherans' cell histiocytic granuloma are most common in the skeletal system affecting, in order of frequency, the skull, the long bones of the limbs, the foot, the ribs and the spine. The oral mucosa is rarely involved. Conclusions: The radiological investigation of unifocal Langherans' cell histiocytic granuloma of the mandible is essential in the study of perimandibular swelling, although diagnosis is based on biopsy alone. In addition to digital or conventional radiography, other useful examinations are bone scintigraphy, Colour Doppler US, MR and CT, which enables a correct localisation necessary for planning the biopsy and treatment. [Italian] Scopo: La diagnosi radiologica delle lesioni osteolitiche della mandibola costituisce un problema

  7. Synthesis, Characterization, and Ultrafast Dynamics of Metal, Metal Oxide, and Semiconductor Nanomaterials

    OpenAIRE

    Wheeler, Damon Andreas

    2013-01-01

    SYNTHESIS, CHARACTERIZATION, AND ULTRAFAST DYNAMICS OF METAL, METAL OXIDE, AND SEMICONDUCTOR NANOMATERIALSABSTRACTThe optical properties of each of the three main classes of inorganic nanomaterials, metals, metal oxides, and semiconductors differ greatly due to the intrinsically different nature of the materials. These optical properties are among the most fascinating and useful aspects of nanomaterials with applications spanning cancer treatment, sensors, lasers, and solar cells. One techn...

  8. Nonequilibrium and Nonlinear Dynamics in Geomaterials I : The Low Strain Regime

    OpenAIRE

    Pasqualini, Donatella; Heitmann, Katrin; TenCate, James A.; Habib, Salman; Higdon, David; Johnson, Paul A.

    2006-01-01

    Members of a wide class of geomaterials are known to display complex and fascinating nonlinear and nonequilibrium dynamical behaviors over a wide range of bulk strains, down to surprisingly low values, e.g., 10^{-7}. In this paper we investigate two sandstones, Berea and Fontainebleau, and characterize their behavior under the influence of very small external forces via carefully controlled resonant bar experiments. By reducing environmental effects due to temperature and humidity variations,...

  9. General Information about Langerhans Cell Histiocytosis (LCH)

    Science.gov (United States)

    ... speaking. Trouble seeing. Headaches. Changes in behavior or personality. Memory problems. These signs and symptoms may be ... National Institutes of Health FOLLOW US Facebook Twitter Instagram YouTube Google+ LinkedIn GovDelivery RSS CONTACT INFORMATION Contact ...

  10. Pulmonary Langerhans Cell Histiocytosis Case with Diabetes ...

    African Journals Online (AJOL)

    2016-07-12

    Jul 12, 2016 ... thin-walled cystic lesions in different sizes more dominantly in the upper lobes and consolidated areas ... zones inside, which started from the hilar region on ... increase of infiltrations in the control PA radiography. Right lung ...

  11. Histiocytosis X | Mohammed | Annals of African Medicine

    African Journals Online (AJOL)

    Annals of African Medicine. Journal Home · ABOUT · Advanced Search · Current Issue · Archives · Journal Home > Vol 8, No 1 (2009) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should load here if your Web ...

  12. Genetics Home Reference: Langerhans cell histiocytosis

    Science.gov (United States)

    ... as viral infections and environmental toxins, may also influence the development of this complex disorder. Learn more about the ... occur? How can gene mutations affect health and development? More about Mutations and ... in people with no history of the disorder in their family. A few families with multiple cases of Langerhans ...

  13. Atomic energy law after the opt-out. Alive and fascinating. Report about the 14{sup th} German atomic energy law symposium 2012; Atomrecht nach dem Ausstieg. Lebendig und spannend. Tagungsbericht 14. Deutsches Atomrechtssymposium 2012

    Energy Technology Data Exchange (ETDEWEB)

    Leidinger, Tobias [Gleiss Lutz Rechtsanwaelte, Duesseldorf (Germany)

    2013-01-15

    Atomic energy law remains a living, fascinating subject matter. Nearly 200 participants were convinced of this impression at the 14{sup th} German Atomic Energy Law Symposium held in Berlin on November 19-20, 2012. Under the scientific chairmanship of Professor Dr. Martin Burgi, Ludwig Maximilian University of Munich, the German Federal Ministry for the Environment, Nature Conservation and Nuclear Safety (BMU), after an interruption of 5 years, again organized a scientific conference about practice-related topics of atomic energy and radiation protection law. Atomic energy law once again proved to be a reference area for sophisticated issues of constitutional law and administrative law above and beyond its technical confines. The agenda of the 14{sup th} German Atomic Energy Law Symposium featured a broad spectrum of topics ranging from backfitting of nuclear power plants to European atomic energy and radiation protection law, to challenges facing national legal systems in the execution of atomic energy law, to legal issues connected with decommissioning and waste management, and on to the topical subject of finding a repository site. The 14{sup th} German Atomic Energy Law Symposium, on the whole, again demonstrated that an open discourse between science and practice is able to furnish important contributions to the implementation of laws in a balanced way rooted in practice. Especially the contributions dealing with the independence of public authorities and their organization, the doctrine of the reservation of functions of the executive branch, and planning by laws contain additional provisions able to influence the continued development of administrative law also above and beyond atomic energy law. The BMU also referred to a decision just heard from Brussels to the effect that a new European Safety Directive would be published as early as in 2013. As a consequence of the nuclear stress tests conducted EU-wide, the Directive is to lay down provisions about

  14. Sync or anti-sync – dynamical pattern selection in coupled self-sustained oscillator systems

    International Nuclear Information System (INIS)

    Davidova, Larissa; Újvári, Szeréna; Néda, Zoltán

    2014-01-01

    The dynamics of similar, self-sustained oscillators coupled by a common platform exhibits fascinating collective behavior. Experiments performed with pendulum clocks and metronomes reported both the absence of synchronization, in-phase synchronization, antiphase synchronization, beat-death phenomenon, or even chaotic dynamics. Here we present a numerical study on two identical self-sustained oscillators placed on a common movable platform. As order parameter for synchronization we use the Pearson correlation coefficient between the oscillators coordinates. As a function of the relevant physical parameters of this system we reproduce all the experimentally reported dynamics. We provide conditions for obtaining stable and emergent in-phase or anti-phase synchronization.

  15. Complex and adaptive dynamical systems a primer

    CERN Document Server

    Gros, Claudius

    2007-01-01

    We are living in an ever more complex world, an epoch where human actions can accordingly acquire far-reaching potentialities. Complex and adaptive dynamical systems are ubiquitous in the world surrounding us and require us to adapt to new realities and the way of dealing with them. This primer has been developed with the aim of conveying a wide range of "commons-sense" knowledge in the field of quantitative complex system science at an introductory level, providing an entry point to this both fascinating and vitally important subject. The approach is modular and phenomenology driven. Examples of emerging phenomena of generic importance treated in this book are: -- The small world phenomenon in social and scale-free networks. -- Phase transitions and self-organized criticality in adaptive systems. -- Life at the edge of chaos and coevolutionary avalanches resulting from the unfolding of all living. -- The concept of living dynamical systems and emotional diffusive control within cognitive system theory. Techn...

  16. Complex and Adaptive Dynamical Systems A Primer

    CERN Document Server

    Gros, Claudius

    2011-01-01

    We are living in an ever more complex world, an epoch where human actions can accordingly acquire far-reaching potentialities. Complex and adaptive dynamical systems are ubiquitous in the world surrounding us and require us to adapt to new realities and the way of dealing with them. This primer has been developed with the aim of conveying a wide range of "commons-sense" knowledge in the field of quantitative complex system science at an introductory level, providing an entry point to this both fascinating and vitally important subject. The approach is modular and phenomenology driven. Examples of emerging phenomena of generic importance treated in this book are: -- The small world phenomenon in social and scale-free networks. -- Phase transitions and self-organized criticality in adaptive systems. -- Life at the edge of chaos and coevolutionary avalanches resulting from the unfolding of all living. -- The concept of living dynamical systems and emotional diffusive control within cognitive system theory. Techn...

  17. Traffic flow dynamics data, models and simulation

    CERN Document Server

    Treiber, Martin

    2013-01-01

    This textbook provides a comprehensive and instructive coverage of vehicular traffic flow dynamics and modeling. It makes this fascinating interdisciplinary topic, which to date was only documented in parts by specialized monographs, accessible to a broad readership. Numerous figures and problems with solutions help the reader to quickly understand and practice the presented concepts. This book is targeted at students of physics and traffic engineering and, more generally, also at students and professionals in computer science, mathematics, and interdisciplinary topics. It also offers material for project work in programming and simulation at college and university level. The main part, after presenting different categories of traffic data, is devoted to a mathematical description of the dynamics of traffic flow, covering macroscopic models which describe traffic in terms of density, as well as microscopic many-particle models in which each particle corresponds to a vehicle and its driver. Focus chapters on ...

  18. Natural Antioxidants: Fascinating or Mythical Biomolecules?

    Directory of Open Access Journals (Sweden)

    Johannes Van Staden

    2010-10-01

    Full Text Available Research on the use, properties, characteristics and sources of antioxidants especially phenolic compounds, flavonoids, vitamins, synthetic chemicals and some micronutrients began in the late 18th century. Since then antioxidant research has received considerable attention and over a hundred thousand papers have been published on the subject. This has led to a rampant use of antioxidants in order to try to obtain and preserve optimal health. A number of nutraceuticals and food supplements are frequently fortified with synthetic or natural antioxidants. However, some research outcomes have led to the belief that antioxidants exist as mythical biomolecules. This review provides a critical evaluation of some common in vitro antioxidant capacity methods, and a discussion on the role and controversies surrounding non-enzymatic biomolecules, in particular phenolic compounds and non-phenolic compounds, in oxidative processes in an attempt of stemming the tidal wave that is threatening to swamp the concept of natural antioxidants.

  19. Fascinating world of rare earth research

    International Nuclear Information System (INIS)

    Gschneidner, K.A. Jr.

    1977-01-01

    The first part of this paper concerns some of the notable events which occurred early in the author's career as a rare earther and some of the major events which took place in the two decades 1950 to 1970. The notable changes and advances in the rare earth research world since the 1971 Durham Conference are described in the second and largest part of the paper. The final portion is concerned with actinide developments since 1971

  20. Childhood sarcoidosis: A rare but fascinating disorder

    Directory of Open Access Journals (Sweden)

    Gedalia Abraham

    2008-09-01

    Full Text Available Abstract Childhood sarcoidosis is a rare multisystemic granulomatous disorder of unknown etiology. In the pediatric series reported from the southeastern United States, sarcoidosis had a higher incidence among African Americans. Most reported childhood cases have occurred in patients aged 13–15 years. Macrophages bearing an increased expression of major histocompatibility class (MHC II molecules most likely initiate the inflammatory response of sarcoidosis by presenting an unidentified antigen to CD4+ Th (helper-inducer lymphocytes. A persistent, poorly degradable antigen driven cell-mediated immune response leads to a cytokine cascade, to granuloma formation, and eventually to fibrosis. Frequently observed immunologic features include depression of cutaneous delayed-type hypersensitivity and a heightened helper T cell type 1 (Th1 immune response at sites of disease. Circulating immune complexes, along with signs of B cell hyperactivity, may also be found. The clinical presentation can vary greatly depending upon the organs involved and age of the patient. Two distinct forms of sarcoidosis exist in children. Older children usually present with a multisystem disease similar to the adult manifestations, with frequent hilar lymphadenopathy and pulmonary infiltrations. Early-onset sarcoidosis is a unique form of the disease characterized by the triad of rash, uveitis, and arthritis in children presenting before four years of age. The diagnosis of sarcoidosis is confirmed by demonstrating a typical noncaseating granuloma on a biopsy specimen. Other granulmatous diseases should be reasonably excluded. The current therapy of choice for sarcoidosis in children with multisystem involvement is oral corticosteroids. Methotrexate given orally in low doses has been effective, safe and steroid sparing in some patients. Alternative immunosuppressive agents, such as azathioprine, cyclophosphamide, chlorambucil, and cyclosporine, have been tried in adult cases of sarcoidosis with questionable efficacy. The high toxicity profile of these agents, including an increased risk of lymphoproliferative disorders and carcinomas, has limited their use to patients with severe disease refractory to other agents. Successful steroid sparing treatment with mycophenolate mofetil was described in an adolescent with renal-limited sarcoidosis complicated by renal failure. Novel treatment strategies for sarcoidosis have been developed including the use of TNF-alpha inhibitors, such as infliximab. The long-term course and prognosis is not well established in childhood sarcoidosis, but it appears to be poorer in early-onset disease.

  1. Fascinating serendipity some adventures in fullerene chemistry

    International Nuclear Information System (INIS)

    Braun, T.; Rauch, H.

    2001-01-01

    The lecture is divided to four chapters. Chapter one gives a short overview on the notion of serendipity and the serendipitous discovery of the fullerenes, the third allotropic form of carbon and will try to highlight why this discovery can be considered a revolution in chemistry. The second and third chapters present some results of the author's research group. Neutron irradiation of C 60 in a nuclear reactor has also made possible the serendipitous discovery of a new procedure for synthesis of endohedral C 60 compounds exemplified by the synthesis of many endohedral radio-fullerenes of * X at C 60 type. The fourth chapter of the lecture deals with 'Capture-captive chemistry' as a new typology for molecular containers including fullerenes. (author)

  2. The Fascinating Story of Fossil Fuels

    Science.gov (United States)

    Asimov, Isaac

    1973-01-01

    How this energy source was created, its meaning to mankind, our drastically reduced supply, and why we cannot wait for nature to make more are considered. Today fossil fuels supply 96 percent of the energy used but we must find alternate energy options if we are to combat the energy crisis. (BL)

  3. Fascinating Children with Words through Tradebooks.

    Science.gov (United States)

    Burke, Eileen M.

    Through careful selection of trade books, teachers can promote children's awareness of language. This paper cites numerous trade books that may be used to help children develop appreciation of alliteration, onomatopoeia, rhythm, and rhyme, and it recommends a number of alphabet books, animal stories, and books in which word meanings, interesting…

  4. contemplating allan boesak's fascination with preaching

    African Journals Online (AJOL)

    ... there is not always sufficient emphasis upon ... how that Word can become a living ... democracy, we can get a picture of how political power is structured. With ... South African society, there seem to be no prospects for a better future other than ..... own transgressions and we don't remember our own sins and we miss the ...

  5. Fascinating Organic Transformations: Rational Mechanistic Analysis

    Indian Academy of Sciences (India)

    plan to set up (without government assistance). "Vidyanantha Education. Centre", to promote education, art and culture. R. R ... was initiated in the early decades of this century, .... a computer program to identify appropriate precursors for a.

  6. A fascinating field and a pragmatic enterprise

    DEFF Research Database (Denmark)

    Hjørland, Birger

    2013-01-01

    A reviewer wrote about the book: "I synnerhet Hjørlands kapitel väcker frågor om fältets inriktning och framtid som det hade varit intressant om redaktörerna hade fångat upp och diskuterat i ett avslutande och syntetiserande kapitel. Detta hade kunnat lyfta denna konferensantologi till något mer ...... en spännande samling texter." Hanna Carlsson i Nordisk Tidsskrift for Informationsvidenskab og Kulturformidling: http://www.ntik.dk/2014/Nr1/Carlsson.pdf...

  7. Dynamics and evolution of galactic nuclei (princeton series in astrophysics)

    CERN Document Server

    Merritt, David

    2013-01-01

    Deep within galaxies like the Milky Way, astronomers have found a fascinating legacy of Einstein's general theory of relativity: supermassive black holes. Connected to the evolution of the galaxies that contain these black holes, galactic nuclei are the sites of uniquely energetic events, including quasars, stellar tidal disruptions, and the generation of gravitational waves. This textbook is the first comprehensive introduction to dynamical processes occurring in the vicinity of supermassive black holes in their galactic environment. Filling a critical gap, it is an authoritative resource for astrophysics and physics graduate students, and researchers focusing on galactic nuclei, the astrophysics of massive black holes, galactic dynamics, and gravitational wave detection. It is an ideal text for an advanced graduate-level course on galactic nuclei and as supplementary reading in graduate-level courses on high-energy astrophysics and galactic dynamics. David Merritt summarizes the theoretical work of the las...

  8. Dynamic combinatorial libraries: from exploring molecular recognition to systems chemistry.

    Science.gov (United States)

    Li, Jianwei; Nowak, Piotr; Otto, Sijbren

    2013-06-26

    Dynamic combinatorial chemistry (DCC) is a subset of combinatorial chemistry where the library members interconvert continuously by exchanging building blocks with each other. Dynamic combinatorial libraries (DCLs) are powerful tools for discovering the unexpected and have given rise to many fascinating molecules, ranging from interlocked structures to self-replicators. Furthermore, dynamic combinatorial molecular networks can produce emergent properties at systems level, which provide exciting new opportunities in systems chemistry. In this perspective we will highlight some new methodologies in this field and analyze selected examples of DCLs that are under thermodynamic control, leading to synthetic receptors, catalytic systems, and complex self-assembled supramolecular architectures. Also reviewed are extensions of the principles of DCC to systems that are not at equilibrium and may therefore harbor richer functional behavior. Examples include self-replication and molecular machines.

  9. N=2 supersymmetric dynamics for pedestrians

    CERN Document Server

    Tachikawa, Yuji

    2015-01-01

    Understanding the dynamics of gauge theories is crucial, given the fact that all known interactions are based on the principle of local gauge symmetry. Beyond the perturbative regime, however, this is a notoriously difficult problem. Requiring invariance under supersymmetry turns out to be a suitable tool for analyzing supersymmetric gauge theories over a larger region of the space of parameters. Supersymmetric quantum field theories in four dimensions with extended N=2 supersymmetry are further constrained and have therefore been a fertile field of research in theoretical physics for quite some time. Moreover, there are far-reaching mathematical ramifications that have led to a successful dialogue with differential and algebraic geometry. These lecture notes aim to introduce students of modern theoretical physics to the fascinating developments in the understanding of N=2 supersymmetric gauge theories in a coherent fashion. Starting with a gentle introduction to electric-magnetic duality, the author guides r...

  10. Future Satellite Gravimetry and Earth Dynamics

    CERN Document Server

    Flury, Jakob

    2005-01-01

    Currently, a first generation of dedicated satellite missions for the precise mapping of the Earth’s gravity field is in orbit (CHAMP, GRACE, and soon GOCE). The gravity data from these satellite missions provide us with very new information on the dynamics of planet Earth. In particular, on the mass distribution in the Earth’s interior, the entire water cycle (ocean circulation, ice mass balance, continental water masses, and atmosphere), and on changes in the mass distribution. The results are fascinating, but still rough with respect to spatial and temporal resolution. Technical progress in satellite-to-satellite tracking and in gravity gradiometry will allow more detailed results in the future. In this special issue, Earth scientists develop visions of future applications based on follow-on high-precision satellite gravimetry missions.

  11. Traffic flow dynamics. Data, models and simulation

    Energy Technology Data Exchange (ETDEWEB)

    Treiber, Martin [Technische Univ. Dresden (Germany). Inst. fuer Wirtschaft und Verkehr; Kesting, Arne [TomTom Development Germany GmbH, Berlin (Germany)

    2013-07-01

    First comprehensive textbook of this fascinating interdisciplinary topic which explains advances in a way that it is easily accessible to engineering, physics and math students. Presents practical applications of traffic theory such as driving behavior, stability analysis, stop-and-go waves, and travel time estimation. Presents the topic in a novel and systematic way by addressing both microscopic and macroscopic models with a focus on traffic instabilities. Revised and extended edition of the German textbook ''Verkehrsdynamik und -simulation''. This textbook provides a comprehensive and instructive coverage of vehicular traffic flow dynamics and modeling. It makes this fascinating interdisciplinary topic, which to date was only documented in parts by specialized monographs, accessible to a broad readership. Numerous figures and problems with solutions help the reader to quickly understand and practice the presented concepts. This book is targeted at students of physics and traffic engineering and, more generally, also at students and professionals in computer science, mathematics, and interdisciplinary topics. It also offers material for project work in programming and simulation at college and university level. The main part, after presenting different categories of traffic data, is devoted to a mathematical description of the dynamics of traffic flow, covering macroscopic models which describe traffic in terms of density, as well as microscopic many-particle models in which each particle corresponds to a vehicle and its driver. Focus chapters on traffic instabilities and model calibration/validation present these topics in a novel and systematic way. Finally, the theoretical framework is shown at work in selected applications such as traffic-state and travel-time estimation, intelligent transportation systems, traffic operations management, and a detailed physics-based model for fuel consumption and emissions.

  12. The Stereociliary Paracrystal Is a Dynamic Cytoskeletal Scaffold In Vivo

    Directory of Open Access Journals (Sweden)

    Philsang Hwang

    2015-11-01

    Full Text Available Permanency of mechanosensory stereocilia may be the consequence of low protein turnover or rapid protein renewal. Here, we devise a system, using optical techniques in live zebrafish, to distinguish between these mechanisms. We demonstrate that the stereocilium’s abundant actin cross-linker fascin 2b exchanges, without bias or a phosphointermediate, orders of magnitude faster (t1/2 of 76.3 s than any other known hair bundle protein. To establish the logic of fascin 2b’s exchange, we examine whether filamentous actin is dynamic and detect substantial β-actin exchange within the stereocilium’s paracrystal (t1/2 of 4.08 hr. We propose that fascin 2b’s behavior may enable cross-linking at fast timescales of stereocilia vibration while noninstructively facilitating the slower process of actin exchange. Furthermore, tip protein myosin XVa fully exchanges in hours (t1/2 of 11.6 hr, indicating that delivery of myosin-associated cargo occurs in mature stereocilia. These findings suggest that stereocilia permanency is underpinned by vibrant protein exchange.

  13. Evolutionary dynamics of cooperation in neutral populations

    Science.gov (United States)

    Szolnoki, Attila; Perc, Matjaž

    2018-01-01

    Cooperation is a difficult proposition in the face of Darwinian selection. Those that defect have an evolutionary advantage over cooperators who should therefore die out. However, spatial structure enables cooperators to survive through the formation of homogeneous clusters, which is the hallmark of network reciprocity. Here we go beyond this traditional setup and study the spatiotemporal dynamics of cooperation in a population of populations. We use the prisoner's dilemma game as the mathematical model and show that considering several populations simultaneously gives rise to fascinating spatiotemporal dynamics and pattern formation. Even the simplest assumption that strategies between different populations are payoff-neutral with one another results in the spontaneous emergence of cyclic dominance, where defectors of one population become prey of cooperators in the other population, and vice versa. Moreover, if social interactions within different populations are characterized by significantly different temptations to defect, we observe that defectors in the population with the largest temptation counterintuitively vanish the fastest, while cooperators that hang on eventually take over the whole available space. Our results reveal that considering the simultaneous presence of different populations significantly expands the complexity of evolutionary dynamics in structured populations, and it allows us to understand the stability of cooperation under adverse conditions that could never be bridged by network reciprocity alone.

  14. Wetland restoration, flood pulsing, and disturbance dynamics

    Science.gov (United States)

    Middleton, Beth A.

    1999-01-01

    While it is generally accepted that flood pulsing and disturbance dynamics are critical to wetland viability, there is as yet no consensus among those responsible for wetland restoration about how best to plan for those phenomena or even whether it is really necessary to do so at all. In this groundbreaking book, Dr. Beth Middleton draws upon the latest research from around the world to build a strong case for making flood pulsing and disturbance dynamics integral to the wetland restoration planning process.While the initial chapters of the book are devoted to laying the conceptual foundations, most of the coverage is concerned with demonstrating the practical implications for wetland restoration and management of the latest ecological theory and research. It includes a fascinating case history section in which Dr. Middleton explores the restoration models used in five major North American, European, Australian, African, and Asian wetland projects, and analyzes their relative success from the perspective of flood pulsing and disturbance dynamics planning.Wetland Restoration also features a wealth of practical information useful to all those involved in wetland restoration and management, including: * A compendium of water level tolerances, seed germination, seedling recruitment, adult survival rates, and other key traits of wetland plant species * A bibliography of 1,200 articles and monographs covering all aspects of wetland restoration * A comprehensive directory of wetland restoration ftp sites worldwide * An extensive glossary of essential terms

  15. The many faces of graph dynamics

    Science.gov (United States)

    Pignolet, Yvonne Anne; Roy, Matthieu; Schmid, Stefan; Tredan, Gilles

    2017-06-01

    The topological structure of complex networks has fascinated researchers for several decades, resulting in the discovery of many universal properties and reoccurring characteristics of different kinds of networks. However, much less is known today about the network dynamics: indeed, complex networks in reality are not static, but rather dynamically evolve over time. Our paper is motivated by the empirical observation that network evolution patterns seem far from random, but exhibit structure. Moreover, the specific patterns appear to depend on the network type, contradicting the existence of a ‘one fits it all’ model. However, we still lack observables to quantify these intuitions, as well as metrics to compare graph evolutions. Such observables and metrics are needed for extrapolating or predicting evolutions, as well as for interpolating graph evolutions. To explore the many faces of graph dynamics and to quantify temporal changes, this paper suggests to build upon the concept of centrality, a measure of node importance in a network. In particular, we introduce the notion of centrality distance, a natural similarity measure for two graphs which depends on a given centrality, characterizing the graph type. Intuitively, centrality distances reflect the extent to which (non-anonymous) node roles are different or, in case of dynamic graphs, have changed over time, between two graphs. We evaluate the centrality distance approach for five evolutionary models and seven real-world social and physical networks. Our results empirically show the usefulness of centrality distances for characterizing graph dynamics compared to a null-model of random evolution, and highlight the differences between the considered scenarios. Interestingly, our approach allows us to compare the dynamics of very different networks, in terms of scale and evolution speed.

  16. System dynamics

    International Nuclear Information System (INIS)

    Kim, Do Hun; Mun, Tae Hun; Kim, Dong Hwan

    1999-02-01

    This book introduces systems thinking and conceptual tool and modeling tool of dynamics system such as tragedy of single thinking, accessible way of system dynamics, feedback structure and causal loop diagram analysis, basic of system dynamics modeling, causal loop diagram and system dynamics modeling, information delay modeling, discovery and application for policy, modeling of crisis of agricultural and stock breeding products, dynamic model and lesson in ecosystem, development and decadence of cites and innovation of education forward system thinking.

  17. Dynamical Languages

    Science.gov (United States)

    Xie, Huimin

    The following sections are included: * Definition of Dynamical Languages * Distinct Excluded Blocks * Definition and Properties * L and L″ in Chomsky Hierarchy * A Natural Equivalence Relation * Symbolic Flows * Symbolic Flows and Dynamical Languages * Subshifts of Finite Type * Sofic Systems * Graphs and Dynamical Languages * Graphs and Shannon-Graphs * Transitive Languages * Topological Entropy

  18. Semiclassical dynamics

    International Nuclear Information System (INIS)

    Balazs, N.L.

    1979-01-01

    It is pointed out that in semiclassical dynamics one is encouraged to study the evolution of those curves in phase space which classically represent ensembles corresponding to wave functions. It is shown that the fixed points generate new time scales so that for times longer than the critical times, quantum dynamics will profoundly differ from classical dynamics. (P.L.)

  19. Dynamical Evolution of the Recent Jet in CH Cyg

    Science.gov (United States)

    Karovska, Margarita

    2011-10-01

    We propose to carry out Chandra ACIS-S observations combined with HST/WFC3multi-wavelength imaging of the powerful, multi-component jet which was detectedin 2008 in the nearby symbiotic CH Cyg. CH Cyg is a fascinating system containing an evolved giant and a wind-accreting white dwarf, and it is one of the few symbiotics showing jet activity, especially in X-rays. Our goal is to measure the physical characteristics of the individual jet components, from the central source to the region of interaction with the circumbinary environment, reaching to within a few AU from the source of the jet. We will determine the characteristics of the central source, and of the inner and the outer jet, and the dynamical evolution, including precession, and kinematics of the ejecta.

  20. Nuclear dynamical diffraction using synchrotron radiation

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Dennis Eugene [Stanford Univ., CA (United States)

    1993-05-01

    The scattering of synchrotron radiation by nuclei is extensively explored in this thesis. From the multipole electric field expansion resulting from time-dependent nonrelativistic perturbation theory, a dynamical scattering theory is constructed. This theory is shown, in the many particle limit, to be equivalent to the semi-classical approach where a quantum mechanical scattering amplitude is used in the Maxwell inhomogeneous wave equation. The Moessbauer specimen whose low-lying energy levels were probed is a ferromagnetic lattice of 57Fe embedded in a yttrium iron garnet (YIG) crystal matrix. The hyperfine fields in YIG thin films were studied at low and room temperature using time-resolved quantum beat spectroscopy. Nuclear hyperfine structure quantum beats were measured using a fast plastic scintillator coincidence photodetector and associated electronics having a time resolution of 2.5 nsec. The variation of the quantum beat patterns near the Bragg [0 0 2] diffraction peak gave a Lamb-Moessbauer factor of 8.2±0.4. Exploring characteristic dynamical features in the higher order YIG [0 0 10] reflection revealed that one of the YIG crystals had bifurcated into two different layers. The dynamics of nuclear superradiance was explored. This phenomenon includes the radiative speedup exhibited by a collective state of particles, and, in striking concurrence, resonance frequency shifts. A speedup of a factor of 4 in the total decay rate and a beat frequency shift of 11/2 natural resonance linewidths were observed. Nuclear resonance scattering was also found to be a useful way of performing angular interferometry experiments, and it was used to observe the phase shift of a rotated quantum state. On the whole, nuclear dynamical diffraction theory has superbly explained many of the fascinating features of resonant magnetic dipole radiation scattered by a lattice of nuclei.

  1. Nuclear dynamical diffraction using synchrotron radiation

    International Nuclear Information System (INIS)

    Brown, D.E.

    1993-05-01

    The scattering of synchrotron radiation by nuclei is extensively explored in this thesis. From the multipole electric field expansion resulting from time-dependent nonrelativistic perturbation theory, a dynamical scattering theory is constructed. This theory is shown, in the many particle limit, to be equivalent to the semi-classical approach where a quantum mechanical scattering amplitude is used in the Maxwell inhomogeneous wave equation. The Moessbauer specimen whose low-lying energy levels were probed is a ferromagnetic lattice of 57 Fe embedded in a yttrium iron garnet (YIG) crystal matrix. The hyperfine fields in YIG thin films were studied at low and room temperature using time-resolved quantum beat spectroscopy. Nuclear hyperfine structure quantum beats were measured using a fast plastic scintillator coincidence photodetector and associated electronics having a time resolution of 2.5 nsec. The variation of the quantum beat patterns near the Bragg [0 0 2] diffraction peak gave a Lamb-Moessbauer factor of 8.2±0.4. Exploring characteristic dynamical features in the higher order YIG [0 0 10] reflection revealed that one of the YIG crystals had bifurcated into two different layers. The dynamics of nuclear superradiance was explored. This phenomenon includes the radiative speedup exhibited by a collective state of particles, and, in striking concurrence, resonance frequency shifts. A speedup of a factor of 4 in the total decay rate and a beat frequency shift of 1 1/2 natural resonance linewidths were observed. Nuclear resonance scattering was also found to be a useful way of performing angular interferometry experiments, and it was used to observe the phase shift of a rotated quantum state. On the whole, nuclear dynamical diffraction theory has superbly explained many of the fascinating features of resonant magnetic dipole radiation scattered by a lattice of nuclei

  2. Discrete dynamics versus analytic dynamics

    DEFF Research Database (Denmark)

    Toxværd, Søren

    2014-01-01

    For discrete classical Molecular dynamics obtained by the “Verlet” algorithm (VA) with the time increment h there exists a shadow Hamiltonian H˜ with energy E˜(h) , for which the discrete particle positions lie on the analytic trajectories for H˜ . Here, we proof that there, independent...... of such an analytic analogy, exists an exact hidden energy invariance E * for VA dynamics. The fact that the discrete VA dynamics has the same invariances as Newtonian dynamics raises the question, which of the formulations that are correct, or alternatively, the most appropriate formulation of classical dynamics....... In this context the relation between the discrete VA dynamics and the (general) discrete dynamics investigated by Lee [Phys. Lett. B122, 217 (1983)] is presented and discussed....

  3. The three-body problem and the equations of dynamics Poincaré’s foundational work on dynamical systems theory

    CERN Document Server

    Poincaré, Henri

    2017-01-01

    Here is an accurate and readable translation of a seminal article by Henri Poincaré that is a classic in the study of dynamical systems popularly called chaos theory. In an effort to understand the stability of orbits in the solar system, Poincaré applied a Hamiltonian formulation to the equations of planetary motion and studied these differential equations in the limited case of three bodies to arrive at properties of the equations’ solutions, such as orbital resonances and horseshoe orbits. Poincaré wrote for professional mathematicians and astronomers interested in celestial mechanics and differential equations. Contemporary historians of math or science and researchers in dynamical systems and planetary motion with an interest in the origin or history of their field will find his work fascinating. .

  4. Dynamics Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — The Dynamics Lab replicates vibration environments for every Navy platform. Testing performed includes: Flight Clearance, Component Improvement, Qualification, Life...

  5. Dynamical systems

    CERN Document Server

    Sternberg, Shlomo

    2010-01-01

    Celebrated mathematician Shlomo Sternberg, a pioneer in the field of dynamical systems, created this modern one-semester introduction to the subject for his classes at Harvard University. Its wide-ranging treatment covers one-dimensional dynamics, differential equations, random walks, iterated function systems, symbolic dynamics, and Markov chains. Supplementary materials offer a variety of online components, including PowerPoint lecture slides for professors and MATLAB exercises.""Even though there are many dynamical systems books on the market, this book is bound to become a classic. The the

  6. Neutral Theory and Scale-Free Neural Dynamics

    Science.gov (United States)

    Martinello, Matteo; Hidalgo, Jorge; Maritan, Amos; di Santo, Serena; Plenz, Dietmar; Muñoz, Miguel A.

    2017-10-01

    Neural tissues have been consistently observed to be spontaneously active and to generate highly variable (scale-free distributed) outbursts of activity in vivo and in vitro. Understanding whether these heterogeneous patterns of activity stem from the underlying neural dynamics operating at the edge of a phase transition is a fascinating possibility, as criticality has been argued to entail many possible important functional advantages in biological computing systems. Here, we employ a well-accepted model for neural dynamics to elucidate an alternative scenario in which diverse neuronal avalanches, obeying scaling, can coexist simultaneously, even if the network operates in a regime far from the edge of any phase transition. We show that perturbations to the system state unfold dynamically according to a "neutral drift" (i.e., guided only by stochasticity) with respect to the background of endogenous spontaneous activity, and that such a neutral dynamics—akin to neutral theories of population genetics and of biogeography—implies marginal propagation of perturbations and scale-free distributed causal avalanches. We argue that causal information, not easily accessible to experiments, is essential to elucidate the nature and statistics of neural avalanches, and that neutral dynamics is likely to play an important role in the cortex functioning. We discuss the implications of these findings to design new empirical approaches to shed further light on how the brain processes and stores information.

  7. Dynamic Capabilities

    DEFF Research Database (Denmark)

    Grünbaum, Niels Nolsøe; Stenger, Marianne

    2013-01-01

    The findings reveal a positive relationship between dynamic capabilities and innovation performance in the case enterprises, as we would expect. It was, however, not possible to establish a positive relationship between innovation performance and profitability. Nor was there any positive...... relationship between dynamic capabilities and profitability....

  8. Nonlinear dynamical triggering of slow slip

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Paul A [Los Alamos National Laboratory; Knuth, Matthew W [WISCONSIN; Kaproth, Bryan M [PENN STATE; Carpenter, Brett [PENN STATE; Guyer, Robert A [Los Alamos National Laboratory; Le Bas, Pierre - Yves [Los Alamos National Laboratory; Daub, Eric G [Los Alamos National Laboratory; Marone, Chris [PENN STATE

    2010-12-10

    Among the most fascinating, recent discoveries in seismology have been the phenomena of triggered slip, including triggered earthquakes and triggered-tremor, as well as triggered slow, silent-slip during which no seismic energy is radiated. Because fault nucleation depths cannot be probed directly, the physical regimes in which these phenomena occur are poorly understood. Thus determining physical properties that control diverse types of triggered fault sliding and what frictional constitutive laws govern triggered faulting variability is challenging. We are characterizing the physical controls of triggered faulting with the goal of developing constitutive relations by conducting laboratory and numerical modeling experiments in sheared granular media at varying load conditions. In order to simulate granular fault zone gouge in the laboratory, glass beads are sheared in a double-direct configuration under constant normal stress, while subject to transient perturbation by acoustic waves. We find that triggered, slow, silent-slip occurs at very small confining loads ({approx}1-3 MPa) that are smaller than those where dynamic earthquake triggering takes place (4-7 MPa), and that triggered slow-slip is associated with bursts of LFE-like acoustic emission. Experimental evidence suggests that the nonlinear dynamical response of the gouge material induced by dynamic waves may be responsible for the triggered slip behavior: the slip-duration, stress-drop and along-strike slip displacement are proportional to the triggering wave amplitude. Further, we observe a shear-modulus decrease corresponding to dynamic-wave triggering relative to the shear modulus of stick-slips. Modulus decrease in response to dynamical wave amplitudes of roughly a microstrain and above is a hallmark of elastic nonlinear behavior. We believe that the dynamical waves increase the material non-affine elastic deformation during shearing, simultaneously leading to instability and slow-slip. The inferred

  9. Statics and dynamics of DNA knotting

    Science.gov (United States)

    Orlandini, Enzo

    2018-02-01

    Knots and entanglement in polymers and biopolymers such as DNA and proteins constitute a timely topic that spans various scientific disciplines ranging from physics to chemistry, biology and mathematics. Although in the past many advancements have been made in understanding the equilibrium knotting probability and knot complexity of long polymer chains in solutions, many questions have been addressed in recent years by both experimental and theoretical means—for instance, how the knotting probability depends on the quality of the solvent, the elastic properties of the molecule and its degree of confinement. How knots form, evolve and eventually disappear in a fluctuating chain. Are the equilibrium and non-equilibrium properties of knotted molecules affected by the knot swelling/shrinking dynamics? Moreover, thanks to the great advance in nanotechnology and micromanipulation techniques, nowadays knots can be ‘manually’ tied in a single DNA molecule, followed during their motion along the chains, forced to pass through nanopores, or stretched by external forces or elongational flows. All these experimental approaches allow access to new information on the interplay of topology and polymer physics, and this has opened new perspectives in the field. Here, we provide an overview of the current knowledge of this topic, stressing the main results obtained, including the recent developments in experimental and computational approaches. Since almost all experiments on knotting involve DNA, the review will be mainly focused on the topological properties of this fascinating and biologically relevant molecule.

  10. Jumping Dynamics

    DEFF Research Database (Denmark)

    Sannino, Francesco

    2013-01-01

    paradigm the physical scale and henceforth also the massive spectrum of the theory jump at the lower boundary of the conformal window. In particular we propose that a theory can suddenly jump from a Quantum Chromodynamics type spectrum, at the lower boundary of the conformal window, to a conformal one...... without particle interpretation. The jumping scenario, therefore, does not support a near-conformal dynamics of walking type. We will also discuss the impact of jumping dynamics on the construction of models of dynamical electroweak symmetry breaking....

  11. Galactic dynamics

    CERN Document Server

    Binney, James

    2008-01-01

    Since it was first published in 1987, Galactic Dynamics has become the most widely used advanced textbook on the structure and dynamics of galaxies and one of the most cited references in astrophysics. Now, in this extensively revised and updated edition, James Binney and Scott Tremaine describe the dramatic recent advances in this subject, making Galactic Dynamics the most authoritative introduction to galactic astrophysics available to advanced undergraduate students, graduate students, and researchers. Every part of the book has been thoroughly overhauled, and many section

  12. Space dynamics

    International Nuclear Information System (INIS)

    Corno, S.E.

    1995-01-01

    Analytical methods for Space Dynamics of fission reactors, are presented. It is shown how a few sample problems in space dynamics can be solved, within the one and two group diffusion model, by purely analytical tools, essentially based on Laplace transform and complex Green function techniques. A quite suggestive generalization of this approach, applicable to the fluid core reactors, whose fuel is undergoing a violent mixing, is reported and briefly discussed. (author)

  13. Structural Dynamics

    International Nuclear Information System (INIS)

    Kim, Du Gi

    2005-08-01

    This book introduces summary of structural dynamics, the reason of learning of structural dynamics, single-degree of freedom system, simple harmonic vibration and application, numerical analysis method, such as time domain and frequency domain and nonlinear system, multi-degree of freedom system random vibration over discrete distribution, continuous distribution and extreme value distribution, circumstance vibration, earth quake vibration, including input earthquake, and earthquake-resistant design and capacity spectrum method, wind oscillation wave vibration, vibration control and maintenance control.

  14. Structural fluctuation governed dynamic diradical character in pentacene.

    Science.gov (United States)

    Yang, Hongfang; Chen, Mengzhen; Song, Xinyu; Bu, Yuxiang

    2015-06-07

    We unravel intriguing dynamical diradical behavior governed by structural fluctuation in pentacene using ab initio molecular dynamics simulation. In contrast to static equilibrium configuration of pentacene with a closed-shell ground state without diradical character, due to structural fluctuation, some of its dynamical snapshot configurations exhibit an open-shell broken-symmetry singlet ground state with diradical character, and such diradical character presents irregular pulsing behavior in time evolution. Not all structural changes can lead to diradical character, only those involving the shortening of cross-linking C-C bonds and variations of the C-C bonds in polyacetylene chains are the main contributors. This scenario about diradicalization is distinctly different from that in long acenes. The essence is that structural distortion cooperatively raises the HOMO and lowers the LUMO, efficiently reducing the HOMO-LUMO and singlet-triplet energy gaps, which facilitate the formation of a broken-symmetry open-shell singlet state. The irregular pulsing behavior originates from the mixing of normal vibrations in pentacene. This fascinating behavior suggests the potential application of pentacene as a suitable building block in the design of new electronic devices due to its magnetism-controllability through energy induction. This work provides new insight into inherent electronic property fluctuation in acenes.

  15. Percutaneous vertebroplasty in osteoporosis, myeloma and Langerhans' cell histiocytosis.

    LENUS (Irish Health Repository)

    Kevane, B

    2012-01-09

    This review aims to assess the effectiveness of percutaneous vertebroplasty as a treatment for the severe refractory pain associated with vertebral fracture, in a group of patients with fractures secondary to either osteoporotic or neoplastic disease. A retrospective review of 20 patients treated with percutaneous vertebroplasty in Cork University Hospital up until March 2007 was carried out and a questionnaire was prepared and distributed. Prior to vertebroplasty, patients had been symptomatic with severe pain for a mean of 20.9 weeks. Of those thirteen whom replied to a postal questionnaire, 12 (92.3%) reported pain relief and this improvement occurred within 7 days in 9 (81.8%). This was associated with decreased analgesic requirements, as determined on chart review. Prior to the procedure only 5 (38.4%) were independently mobile and this figure rose to 10 (76.9%) afterwards, occurring within one week in the majority. Subjective outcomes were better in the group of patients with neoplasm-induced fractures.

  16. Langerhans cell histiocytosis: A case presentation and literature ...

    African Journals Online (AJOL)

    evaluation imaging (skeletal survey, skeletal isotopes and CT ... recent imaging confirmed that he still has .... include small stature, growth hormone deficiency, hypothyroidism, ... lesions or multisystem non-risk organ involvement, even a short.

  17. Sinus histiocytosis with massive lymphadenopathy: MRI findings of osseous lesions

    Energy Technology Data Exchange (ETDEWEB)

    Lin, J. [Dept. of Radiology, Univ. of Illinois Hospital, Chicago, IL (United States); Lazarus, M. [Dept. of Radiology, Univ. of Illinois Hospital, Chicago, IL (United States); Wilbur, A. [Dept. of Radiology, Univ. of Illinois Hospital, Chicago, IL (United States)

    1996-04-01

    The case of a 20-year-old female with SHML and osseous involvement is presented. We describe three different patterns of involvement in the diametaphyseal portions of the long bones with similar MRI signal characteristics. (orig.)

  18. Genetics Home Reference: histiocytosis-lymphadenopathy plus syndrome

    Science.gov (United States)

    ... body. ENT3 is found in cellular structures called lysosomes , which break down large molecules into smaller ones ... the breakdown of DNA and RNA out of lysosomes into the cell so they can be reused. ...

  19. Dynamic Bifurcations

    CERN Document Server

    1991-01-01

    Dynamical Bifurcation Theory is concerned with the phenomena that occur in one parameter families of dynamical systems (usually ordinary differential equations), when the parameter is a slowly varying function of time. During the last decade these phenomena were observed and studied by many mathematicians, both pure and applied, from eastern and western countries, using classical and nonstandard analysis. It is the purpose of this book to give an account of these developments. The first paper, by C. Lobry, is an introduction: the reader will find here an explanation of the problems and some easy examples; this paper also explains the role of each of the other paper within the volume and their relationship to one another. CONTENTS: C. Lobry: Dynamic Bifurcations.- T. Erneux, E.L. Reiss, L.J. Holden, M. Georgiou: Slow Passage through Bifurcation and Limit Points. Asymptotic Theory and Applications.- M. Canalis-Durand: Formal Expansion of van der Pol Equation Canard Solutions are Gevrey.- V. Gautheron, E. Isambe...

  20. Dynamic Pricing

    DEFF Research Database (Denmark)

    Sharifi, Reza; Anvari-Moghaddam, Amjad; Fathi, S. Hamid

    2017-01-01

    Dynamic pricing scheme, also known as real-time pricing (RTP), can be more efficient and technically beneficial than the other price-based schemes (such as flat-rate or time-of-use (TOU) pricing) for enabling demand response (DR) actions. Over the past few years, advantages of RTP-based schemes h...... of dynamic pricing can lead to increased willingness of consumers to participate in DR programs which in turn improve the operation of liberalized electricity markets.......Dynamic pricing scheme, also known as real-time pricing (RTP), can be more efficient and technically beneficial than the other price-based schemes (such as flat-rate or time-of-use (TOU) pricing) for enabling demand response (DR) actions. Over the past few years, advantages of RTP-based schemes...

  1. Record dynamics

    DEFF Research Database (Denmark)

    Robe, Dominic M.; Boettcher, Stefan; Sibani, Paolo

    2016-01-01

    When quenched rapidly beyond their glass transition, colloidal suspensions fall out of equilibrium. The pace of their dynamics then slows down with the system age, i.e., with the time elapsed after the quench. This breaking of time translational invariance is associated with dynamical observables...... which depend on two time-arguments. The phenomenology is shared by a broad class of aging systems and calls for an equally broad theoretical description. The key idea is that, independent of microscopic details, aging systems progress through rare intermittent structural relaxations that are de......-facto irreversible and become increasingly harder to achieve. Thus, a progression of record-sized dynamical barriers are traversed in the approach to equilibration. Accordingly, the statistics of the events is closely described by a log-Poisson process. Originally developed for relaxation in spin glasses...

  2. Dynamical theory of dense groups of galaxies

    Science.gov (United States)

    Mamon, Gary A.

    1990-01-01

    It is well known that galaxies associate in groups and clusters. Perhaps 40% of all galaxies are found in groups of 4 to 20 galaxies (e.g., Tully 1987). Although most groups appear to be so loose that the galaxy interactions within them ought to be insignificant, the apparently densest groups, known as compact groups appear so dense when seen in projection onto the plane of the sky that their members often overlap. These groups thus appear as dense as the cores of rich clusters. The most popular catalog of compact groups, compiled by Hickson (1982), includes isolation among its selection critera. Therefore, in comparison with the cores of rich clusters, Hickson's compact groups (HCGs) appear to be the densest isolated regions in the Universe (in galaxies per unit volume), and thus provide in principle a clean laboratory for studying the competition of very strong gravitational interactions. The $64,000 question here is then: Are compact groups really bound systems as dense as they appear? If dense groups indeed exist, then one expects that each of the dynamical processes leading to the interaction of their member galaxies should be greatly enhanced. This leads us to the questions: How stable are dense groups? How do they form? And the related question, fascinating to any theorist: What dynamical processes predominate in dense groups of galaxies? If HCGs are not bound dense systems, but instead 1D change alignments (Mamon 1986, 1987; Walke & Mamon 1989) or 3D transient cores (Rose 1979) within larger looser systems of galaxies, then the relevant question is: How frequent are chance configurations within loose groups? Here, the author answers these last four questions after comparing in some detail the methods used and the results obtained in the different studies of dense groups.

  3. Il fascino dell'economia (A fascination with economics

    Directory of Open Access Journals (Sweden)

    K. BRUNNER

    2013-12-01

    Full Text Available l'articolo è un contributo ad una serie di ricordi e riflessioni sulle esperienze professionali di illustri economisti con Banca Nazionale del Lavoro Quarterly Review iniziate nel 1979. In esso Karl Brunner discute l' evoluzione del suo pensiero sul ruolo e l'uso dell'economia per quanto riguarda  tre problemi distintiThe paper is a contribution to a series of recollections and reflections on the professional experiences of distinguished economists which the Banca Nazionale del Lavoro Quarterly Review started in 1979. In it Karl Brunner discusses the evolution of his thoughts on the role and use of economics with regards to three distinct problems. JEL: B31, A11

  4. Superformed bands in atomic nuclei. A fascinating recent discovery

    International Nuclear Information System (INIS)

    Nazarewicz, W.; Szymanski, Z.

    1990-01-01

    The recent discovery of a new type of exotic state, the so-called superformed (SD) state in rapidly rotating, extremely distorted atomic nuclei has ushered in a new area of physics called high-spin spectroscopy. The measurement of discrete SD states at angular momenta lying in the 40 to 60 ℎ range is fast becoming a standard technique in nuclear γ-ray spectroscopy thanks to improved experimental skills and the introduction of multi-detector arrays. (orig.)

  5. Alpha-fetoprotein, a fascinating protein and biomarker in neurology.

    Science.gov (United States)

    Schieving, J H; de Vries, M; van Vugt, J M G; Weemaes, C; van Deuren, M; Nicolai, J; Wevers, R A; Willemsen, M A

    2014-05-01

    Alpha-fetoprotein (AFP) is present in fetal serum in concentrations up to 5,000,000 μg/l. After birth, AFP gene expression is turned down with a subsequent fall of the serum concentrations of this albumin-like protein to 'adult values' of circa 0.5-15 μg/l from the age of 2 years onwards. Irrespective of its assumed important functions, individuals with AFP deficiency appear fully healthy. The other way around, the presence of AFP in the circulation after the first years of life doesn't seem to harm, since individuals with 'hereditary persistence of AFP' are also without clinical abnormalities. During pregnancy, AFP (in maternal serum) has long been recognized as a marker for congenital anomalies of the fetus. Equally well known is AFP as biomarker for hepatocellular carcinoma and some other malignancies. There are at least four neurodegenerative disorders, all inherited as autosomal recessive traits and characterized by the presence of cerebellar ataxia, abnormal ocular movements, and neuropathy, for which an elevated concentration of serum AFP is an important diagnostic biomarker. The availability of a reliable biomarker is not only important during screening or diagnostic processes, but is also relevant for objective follow-up during (future) therapeutic interventions. Copyright © 2013. Published by Elsevier Ltd.

  6. ATLASES—THE NEW FASCINATION OF FRENCH PUBLISHERS

    Directory of Open Access Journals (Sweden)

    Jean Radvanyi

    2011-01-01

    Full Text Available Reacting to reader interest in publications of new types of atlases, many French authors and publishers rushed to occupy an emerging publishing niche and created a real fashion of small atlases attracting ever-greater public attention. The paper describes origins and features of this phenomenon.

  7. Fascinating Magnetic Energy Storage Nanomaterials: A Brief Review.

    Science.gov (United States)

    Sreenivasulu, Kummari V; Srikanth, Vadali V S S

    2017-07-10

    In this brief review, the importance of nanotechnology in developing novel magnetic energy storage materials is discussed. The discussion covers recent patents on permanent magnetic materials and especially covers processing of permanent magnets (rare-earth and rare-earth free magnets), importance of rare-earth permanent magnets and necessity of rare-earth free permanent magnets. Magnetic energy storage materials are those magnetic materials which exhibit very high energy product (BH)max (where B is the magnetic induction in Gauss (G) whereas H is the applied magnetic field in Oersted (Oe)). (BH)max is the direct measure of the ability of a magnetic material to store energy. In this context, processing of magnetic energy storage composite materials constituted by soft and hard magnetic materials played a predominant role in achieving high (BH)max values due to the exchange coupling phenomenon between the soft and hard magnetic phases within the composite. Magnetic energy storage composites are normally composed of rare-earth magnetic materials as well as rare-earth free magnetic materials. Nanotechnology's influence on the enhancement of energy product due to the exchange coupling phenomenon is of great prominence and therefore discussed in this review. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  8. Marvels of Science: 50 Fascinating 5-minute Reads.

    Science.gov (United States)

    Haven, Kendall

    This book is a collection of 50 stories of the people, events, and processes that give us our rich scientific heritage with the goal of fostering an appreciation for the process of science and for the great variety of personalities that have graced the world of science. In addition to the actual text, each story in this book contains focusing and…

  9. Marvels of Math: Fascinating Reads and Awesome Activities.

    Science.gov (United States)

    Haven, Kendall F.

    Any topic, math included, becomes more accessible and understandable when human stories are related about the development of the subject. Stories make subjects real and purposeful. They provide a foundation from which students can understand and appreciate mathematics rather than merely memorize a series of rote exercises. This book presents 16…

  10. Refresher Course on Water: Its Fascinating Science and Diverse ...

    Indian Academy of Sciences (India)

    IAS Admin

    2015-09-30

    Sep 30, 2015 ... Water is a central ingredient of the natural world on earth, and plays an essential role as the medium in which life exists, and as a major constituent of the planet's surface, plays a central role in many processes and cycles in the natural world around us. An understanding of water in its many dimensions, ...

  11. Use of renewable energies at sea: Fascination Offshore. Report 2002

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-07-01

    Wind energy use experienced an enormous upswing in recent years. In the meantime a wind energy capacity of more than 26,000 MW has been installed worldwide and this positive development appears to continue at the same pace. According to a study of the renowned consulting company BTM Consult an additional capacity of 54,000 MW will be installed in the next five years. Apart from the development in the onshore area and the gained experience, the large-scale technical utilisation of wind power at sea in Europe becomes more and more the focus of attention. The planned wind power plants are supposed to have a capacity between three and five MW and the number of plants in the final extension phase is supposed to amount to 200 plants, which corresponds to an installed capacity of up to 1,000 MW per park. Plans are partly made for plants located between 30 and 40 kilometres from the coast and in water depths of up to 35 meters. Research results about the wind conditions and the location requirements at these distances from the coast are only available to a certain extent. In order to obtain reliable data several research projects have been initiated. In this study you will not only find contributions to the subjects mentioned above but also reports from experts, who explain their knowledge and experience gained from practice. (orig.) [German] Die Windenergienutzung hat in den letzten Jahren einen ernormen Aufschwung erlebt. Mittlerweile sind weltweit mehr als 26.000 MW an Windenergieleistung installiert und diese positive Entwicklung geht offensichtlich ungebremst weiter. Gemaess einer Studie des renommierten Beratungsunternehmens BTM Consult werden in den naechsten fuenf Jahren weitere 54.000 MW errichtet. Neben der Entwicklung im Onshore-Bereich und der dort gesammelten Erfahrung rueckt nun die grosstechnische Nutzung der Windkraft auf dem Meer in Europa immer mehr in den Blickpunkt. Die zum Einsatz kommenden WEA sollen eine Leistung von drei bis fuenf MW haben und die Anlagenzahl betraegt in den Endausbaustufen bis zu 200 Anlagen, was einer installierte Leistung von bis zu 1.000 MW pro Park entspricht. Die Planungen werden zum Teil in Kuestenentfernungen von 30 bis 40 Kilometern und in Wassertiefen bis zu 35 Metern durchgefuehrt. In diesen Entfernungen von der Kueste liegen nur bedingt Forschungsergebnisse ueber Windverhaeltnisse und Standortanforderungen vor. Um hier belastbare Daten zu erhalten sind diverse Forschungsvorhaben initiiert worden. In der Studie finden Sie neben unseren eigenen Ausarbeitungen zu den oben genannten Themenbereichen auch Fachbeitraege von Experten, die aus der Praxis heraus Ihre Erfahrungen und Kenntnisse einfliessen lassen. (orig.)

  12. Single Molecule Fluorescence: from Physical Fascination to Biological Relevance

    NARCIS (Netherlands)

    Segers-Nolten, Gezina M.J.

    2003-01-01

    Confocal fluorescence microscopy is particularly well-known from the beautiful images that have been obtained with this technique from cells. Several cellular components could be nicely visualized simultaneously by staining them with different fluorophores. Not only for ensemble applications but

  13. New Methods for Assessing the Fascinating Nature of Nature Experiences

    NARCIS (Netherlands)

    Joye, Yannick; Pals, Roos; Steg, Linda; Evans, Ben Lewis

    2013-01-01

    In recent years, numerous environmental psychology studies have demonstrated that contact with nature as opposed to urban settings can improve an individual's mood, can lead to increased levels of vitality, and can offer an opportunity to recover from stress. According to Attention Restoration

  14. Entangled world. The fascination of quantum information and computation

    International Nuclear Information System (INIS)

    Audretsch, J.

    2006-01-01

    In the quantum world, a particle can behave like a wave and accordingly seems to be in two places at the same time. This of course is contradictory to our daily experiences with classical particles. How then should this be understood? What happens in the transitional area between the classical world and quantum mechanics? The present book answers exciting questions like these in a way that is easy to follow and to understand and it shows that the link between these two worlds will have concrete and applied effects on our daily life in the near future. It will, for example, improve and change the conventional methods of information processing. With the help of quantum cryptography, it will be possible to communicate tap-proof. Using quantum computers we will be able to solve highly complicated problems in a very short time. (orig.)

  15. The Swedish Bohus granite - a stone with a fascinating history

    Science.gov (United States)

    Schouenborg, Björn; Eliasson, Thomas

    2015-04-01

    One of the most well-known and well spread Swedish stone types used as building stones is the Bonus granite. It outcrops in an area north of Gothenburgh (SW Sweden), along the coastline, approximately 35 km wide and 85 km long. The granite continues into Norway as the Iddefjord granite. The Bohus granite is one of Sweden's youngest granites. Isotopic dating shows that the magma cooled at about 920 M years ago and thus marking the end of the Sveconorwegian orogoney. It is a composite granite massif area with several granitic intrusions but with rather homogeneous mineralogy. However, colour and texture varies quite a lot and the colour ranges from red to reddish grey although some pure grey varieties occur sparsely. The grain size ranges from medium grained to coarse grained and even with some porphyric parts. Quarrying in an industrial scale started 1842. The merchant A C Kullgren opened the first quarry and produced stones for the construction of the 86 km long Trollhättan channel connecting lake Vänern and the Atlantic ocean in the SW Sweden The stone was used for constructing harbors and wharves along the channel. Several quarries opened in the late 1800 around 1870 - 1890 and the export increased steadily with deliveries to Germany, Denmark, Holland, England and even to South America. The stone industries in Bohuslän (Bohus county), at its peak in 1929, engaged around 7 000 employees. During the depression in 1930 almost all of them became unemployed. However, as a curiosity, production and export continued to Germany for construction of Germania, the future World capital city ("Welthauptstadt Germania"), planned by Adolf Hitler and Albert Speer. About 500 stone workers were kept employed for this project during the late thirties. Today several varieties are still produced: Evja/Ävja, Tossene, Brastad, Näsinge, Broberg, Nolby, Allemarken and Skarstad. However, the number of stone workers is far from that of the early 1900. The Swedish production is mainly blocks but also paving products like sets, slabs and kerb stones are still manufactured in Sweden. Blocks are generally further processed in other countries like Italy and China to reach the European market as semi-finished products like slabs or finished products for any kind of application. The granite is very durable and suitable for all types of natural stone products.

  16. Fascinating! Popular Science Communication and Literary Science Fiction

    DEFF Research Database (Denmark)

    Meyer, Gitte

    2017-01-01

    Some see literary Science Fiction as a possible vehicle for critical discussions about the future development and the ethical implications of science-based technologies. According to that understanding, literary Science Fiction constitutes a variety of science communication. Along related lines, ......, popular science communication with science fiction features might be expected to serve a similar purpose. Only, it is far from obvious that it actually works that way.......Some see literary Science Fiction as a possible vehicle for critical discussions about the future development and the ethical implications of science-based technologies. According to that understanding, literary Science Fiction constitutes a variety of science communication. Along related lines...

  17. Single Molecule Fluorescence: from Physical Fascination to Biological Relevance

    OpenAIRE

    Segers-Nolten, Gezina M.J.

    2003-01-01

    Confocal fluorescence microscopy is particularly well-known from the beautiful images that have been obtained with this technique from cells. Several cellular components could be nicely visualized simultaneously by staining them with different fluorophores. Not only for ensemble applications but also in single molecule research confocal fluorescence microscopy became a popular technique. In this thesis the possibilities are shown to study a complicated biological process, which is Nucleotide ...

  18. Fascinating and forgotten: the conservation status of marine elapid snakes

    DEFF Research Database (Denmark)

    2013-01-01

    Australia. Three of the seven threatened species occur at Ashmore and Hibernia Reefs in the Timor Sea, while the remaining threatened taxa occur in the Philippines, Niue, and Solomon Islands. The majority of Data Deficient species are found in Southeast Asia. Threats to marine snakes include loss of coral...... reefs and coastal habitat, incidental bycatch in fisheries, as well as fisheries that target snakes for leather. The presence of two Critically Endangered and one Endangered species in the Timor Sea suggests the area is of particular conservation concern. More rigorous, long-term monitoring...

  19. Dynamical systems

    CERN Document Server

    Birkhoff, George D

    1927-01-01

    His research in dynamics constitutes the middle period of Birkhoff's scientific career, that of maturity and greatest power. -Yearbook of the American Philosophical Society The author's great book€¦is well known to all, and the diverse active modern developments in mathematics which have been inspired by this volume bear the most eloquent testimony to its quality and influence. -Zentralblatt MATH In 1927, G. D. Birkhoff wrote a remarkable treatise on the theory of dynamical systems that would inspire many later mathematicians to do great work. To a large extent, Birkhoff was writing about his o

  20. Glassy Dynamics

    DEFF Research Database (Denmark)

    Jensen, Henrik J.; Sibani, Paolo

    2007-01-01

    The term glassy dynamics is often used to refer to the extremely slow relaxation observed in several types of many component systems. The time span needed to reach a steady, time independent, state will typically be far beyond experimentally accessible time scales. When melted alloys are cooled...... down they typically do not enter a crystalline ordered state. Instead the atoms retain the amorphous arrangement characteristic of the liquid high temperature phase while the mobility of the molecules decreases very many orders of magnitude. This colossal change in the characteristic dynamical time...

  1. Forest dynamics.

    Science.gov (United States)

    Frelich, Lee

    2016-01-01

    Forest dynamics encompass changes in stand structure, species composition, and species interactions with disturbance and environment over a range of spatial and temporal scales. For convenience, spatial scale is defined as individual tree, neighborhood, stand, and landscape. Whether a given canopy-leveling disturbance will initiate a sequence of development in structure with little change in composition or initiate an episode of succession depends on a match or mismatch, respectively, with traits of the dominant tree species that allow the species to survive disturbance. When these match, certain species-disturbance type combinations lock in a pattern of stand and landscape dynamics that can persist for several generations of trees; thus, dominant tree species regulate, as well as respond to, disturbance. A complex interaction among tree species, neighborhood effects, disturbance type and severity, landform, and soils determines how stands of differing composition form and the mosaic of stands that compose the landscape. Neighborhood effects (e.g., serotinous seed rain, sprouting, shading, leaf-litter chemistry, and leaf-litter physical properties) operate at small spatial extents of the individual tree and its neighbors but play a central role in forest dynamics by contributing to patch formation at stand scales and dynamics of the entire landscape. Dominance by tree species with neutral to negative neighborhood effects leads to unstable landscape dynamics in disturbance-prone regions, wherein most stands are undergoing succession; stability can only occur under very low-severity disturbance regimes. Dominance by species with positive effects leads to stable landscape dynamics wherein only a small proportion of stands undergo succession at any one time. Positive neighborhood effects are common in temperate and boreal zones, whereas negative effects are more common in tropical climates. Landscapes with positive dynamics have alternate categories of dynamics

  2. Classical dynamics

    CERN Document Server

    Greenwood, Donald T

    1997-01-01

    Graduate-level text for science and technology students provides strong background in the more abstract and intellectually satisfying areas of dynamical theory. Topics include d'Alembert's principle and the idea of virtual work, Hamilton's equations, Hamilton-Jacobi theory, canonical transformations, more. Problems and references at chapter ends.

  3. Expansion dynamics

    International Nuclear Information System (INIS)

    Knoll, J.

    1985-10-01

    A quantum dynamical model is suggested which describes the expansion and disassembly phase of highly excited compounds formed in energetic heavy-ion collisions. First applications in two space and one time dimensional model world are discussed and qualitatively compared to standard freeze-out concepts. (orig.)

  4. Membrane dynamics

    DEFF Research Database (Denmark)

    Bendix, Pól Martin

    2015-01-01

    Current topics include membrane-protein interactions with regard to membrane deformation or curvature sensing by BAR domains. Also, we study the dynamics of membrane tubes of both cells and simple model membrane tubes. Finally, we study membrane phase behavior which has important implications...... for the lateral organization of membranes as wells as for physical properties like bending, permeability and elasticity...

  5. Random dynamics

    International Nuclear Information System (INIS)

    Bennett, D.L.; Brene, N.; Nielsen, H.B.

    1986-06-01

    The goal of random dynamics is the derivation of the laws of Nature as we know them (standard model) from inessential assumptions. The inessential assumptions made here are expressed as sets of general models at extremely high energies: gauge glass and spacetime foam. Both sets of models lead tentatively to the standard model. (orig.)

  6. Dynamic LIMIDS

    NARCIS (Netherlands)

    Díez, F.J.; Gerven, M.A.J. van; Sucar, L.E.; Morales, E.F.; Hoey, J.

    2011-01-01

    One of the objectives of artificial intelligence is to build decision-support models for systems that evolve over time and include several types of uncertainty. Dynamic limited-memory influence diagrams (DLIMIDs) are a new type of model proposed recently for this kind of problems. DLIMIDs are

  7. System Dynamics

    Science.gov (United States)

    Morecroft, John

    System dynamics is an approach for thinking about and simulating situations and organisations of all kinds and sizes by visualising how the elements fit together, interact and change over time. This chapter, written by John Morecroft, describes modern system dynamics which retains the fundamentals developed in the 1950s by Jay W. Forrester of the MIT Sloan School of Management. It looks at feedback loops and time delays that affect system behaviour in a non-linear way, and illustrates how dynamic behaviour depends upon feedback loop structures. It also recognises improvements as part of the ongoing process of managing a situation in order to achieve goals. Significantly it recognises the importance of context, and practitioner skills. Feedback systems thinking views problems and solutions as being intertwined. The main concepts and tools: feedback structure and behaviour, causal loop diagrams, dynamics, are practically illustrated in a wide variety of contexts from a hot water shower through to a symphony orchestra and the practical application of the approach is described through several real examples of its use for strategic planning and evaluation.

  8. Coastal Dynamics

    NARCIS (Netherlands)

    Roelvink, J.A.; Steetzel, H.J.; Bliek, A.; Rakhorst, H.D.; Roelse, P.; Bakker, W.T.

    1998-01-01

    This book deals on "Coastal Dynamics", which will be defined in a narrow sense as a mathematical theory, which starts from given equations of motion for the sediment, which leads with the continuity equation and given boundary conditions to a calculated (eventually schematized) coastal topography,

  9. Structural dynamics

    CERN Document Server

    Strømmen, Einar N

    2014-01-01

    This book introduces to the theory of structural dynamics, with focus on civil engineering structures that may be described by line-like beam or beam-column type of systems, or by a system of rectangular plates. Throughout this book the mathematical presentation contains a classical analytical description as well as a description in a discrete finite element format, covering the mathematical development from basic assumptions to the final equations ready for practical dynamic response predictions. Solutions are presented in time domain as well as in frequency domain. Structural Dynamics starts off at a basic level and step by step brings the reader up to a level where the necessary safety considerations to wind or horizontal ground motion induced dynamic design problems can be performed. The special theory of the tuned mass damper has been given a comprehensive treatment, as this is a theory not fully covered elsewhere. For the same reason a chapter on the problem of moving loads on beams has been included.

  10. Random dynamics

    International Nuclear Information System (INIS)

    Bennett, D.L.

    1987-01-01

    The goal of random dynamics is the derivation of the laws of Nature as we know them (standard model) from inessential assumptions. The inessential assumptions made here are expressed as sets of general models at extremely high energies: Gauge glass and spacetime foam. Both sets of models lead tentatively to the standard model. (orig.)

  11. Random Dynamics

    Science.gov (United States)

    Bennett, D. L.; Brene, N.; Nielsen, H. B.

    1987-01-01

    The goal of random dynamics is the derivation of the laws of Nature as we know them (standard model) from inessential assumptions. The inessential assumptions made here are expressed as sets of general models at extremely high energies: gauge glass and spacetime foam. Both sets of models lead tentatively to the standard model.

  12. Formation and field-driven dynamics of nematic spheroids.

    Science.gov (United States)

    Fu, Fred; Abukhdeir, Nasser Mohieddin

    2017-07-19

    Unlike the canonical application of liquid crystals (LCs), LC displays, emerging technologies based on LC materials are increasingly leveraging the presence of nanoscale defects. The inherent nanoscale characteristics of LC defects present both significant opportunities as well as barriers for the application of this fascinating class of materials. Simulation-based approaches to the study of the effects of confinement and interface anchoring conditions on LC domains has resulted in significant progress over the past decade, where simulations are now able to access experimentally-relevant length scales while simultaneously capturing nanoscale defect structures. In this work, continuum simulations were performed in order to study the dynamics of micron-scale nematic LC spheroids of varying shape. Nematic spheroids are one of the simplest inherently defect-containing LC structures and are relevant to polymer-dispersed LC-based "smart" window technology. Simulation results include nematic phase formation and external field-switching dynamics of nematic spheroids ranging in shape from oblate to prolate. Results include both qualitative and quantitative insight into the complex coupling of nanoscale defect dynamics and structure transitions to micron-scale reorientation. Dynamic mechanisms are presented and related to structural transitions in LC defects present in the nematic domain. Domain-averaged metrics including order parameters and response times are determined for a range of experimentally-accessible electric field strengths. These results have both fundamental and technological relevance, in that increased understanding of LC dynamics in the presence of defects is a key barrier to continued advancement in the field.

  13. Applied dynamics

    CERN Document Server

    Schiehlen, Werner

    2014-01-01

    Applied Dynamics is an important branch of engineering mechanics widely applied to mechanical and automotive engineering, aerospace and biomechanics as well as control engineering and mechatronics. The computational methods presented are based on common fundamentals. For this purpose analytical mechanics turns out to be very useful where D’Alembert’s principle in the Lagrangian formulation proves to be most efficient. The method of multibody systems, finite element systems and continuous systems are treated consistently. Thus, students get a much better understanding of dynamical phenomena, and engineers in design and development departments using computer codes may check the results more easily by choosing models of different complexity for vibration and stress analysis.

  14. Delta Dynamics

    DEFF Research Database (Denmark)

    Bendixen, Mette

    . The warming air temperature affects the soil temperature and permafrost thaws and destabilizes the material in the coastal zone. In Greenland, the warming temperature lowers the surface mass balance of the Greenland Ice Sheet and more material is transported to the coastal zone. The sea ice extent is thinning...... of a fjord and the second type is a wider fan-shaped open delta. Most deltas are directly coupled to the Greenland Ice Sheet or local icecaps and are highly influenced by the dynamics in the catchments. It is demonstrated how a modern changing climate directly affects delta dynamics, and that Greenlandic...... deltas are prograding, contrary to the global trend showing eroding Arctic coasts. Moreover, it is revealed that the increasing proglacial freshwater runoff, caused by a lowering of the surface mass balance of the Greenland Ice Sheet is the main determining agent in delta progradation. The final part...

  15. Fluid dynamics

    CERN Document Server

    Bernard, Peter S

    2015-01-01

    This book presents a focused, readable account of the principal physical and mathematical ideas at the heart of fluid dynamics. Graduate students in engineering, applied math, and physics who are taking their first graduate course in fluids will find this book invaluable in providing the background in physics and mathematics necessary to pursue advanced study. The book includes a detailed derivation of the Navier-Stokes and energy equations, followed by many examples of their use in studying the dynamics of fluid flows. Modern tensor analysis is used to simplify the mathematical derivations, thus allowing a clearer view of the physics. Peter Bernard also covers the motivation behind many fundamental concepts such as Bernoulli's equation and the stream function. Many exercises are designed with a view toward using MATLAB or its equivalent to simplify and extend the analysis of fluid motion including developing flow simulations based on techniques described in the book.

  16. Superconductor Dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Gömöry, F [Bratislava, Inst. Elect. Eng. (Slovakia)

    2014-07-01

    Superconductors used in magnet technology could carry extreme currents because of their ability to keep the magnetic flux motionless. The dynamics of the magnetic flux interaction with superconductors is controlled by this property. The cases of electrical transport in a round wire and the magnetization of wires of various shapes (circular, elliptical, plate) in an external magnetic field are analysed. Resistance to the magnetic field penetration means that the field produced by the superconducting magnet is no longer proportional to the supplied current. It also leads to a dissipation of electromagnetic energy. In conductors with unequal transverse dimensions, such as flat cables, the orientation with respect to the magnetic field plays an essential role. A reduction of magnetization currents can be achieved by splitting the core of a superconducting wire into fine filaments; however, new kinds of electrical currents that couple the filaments consequently appear. Basic formulas allowing qualitative analyses of various flux dynamic cases are presented.

  17. Beam dynamics

    International Nuclear Information System (INIS)

    Abell, D; Adelmann, A; Amundson, J; Dragt, A; Mottershead, C; Neri, F; Pogorelov, I; Qiang, J; Ryne, R; Shalf, J; Siegerist, C; Spentzouris, P; Stern, E; Venturini, M; Walstrom, P

    2006-01-01

    We describe some of the accomplishments of the Beam Dynamics portion of the SciDAC Accelerator Science and Technology project. During the course of the project, our beam dynamics software has evolved from the era of different codes for each physical effect to the era of hybrid codes combining start-of-the-art implementations for multiple physical effects to the beginning of the era of true multi-physics frameworks. We describe some of the infrastructure that has been developed over the course of the project and advanced features of the most recent developments, the interplay betwen beam studies and simulations and applications to current machines at Fermilab. Finally we discuss current and future plans for simulations of the International Linear Collider

  18. Application of Hybrid Dynamical Theory to the Cardiovascular System

    KAUST Repository

    Laleg-Kirati, Taous-Meriem

    2014-10-14

    In hybrid dynamical systems, the state evolves in continuous time as well as in discrete modes activated by internal conditions or by external events. In the recent years, hybrid systems modeling has been used to represent the dynamics of biological systems. In such systems, discrete behaviors might originate from unexpected changes in normal performance, e.g., a transition from a healthy to an abnormal condition. Simplifications, model assumptions, and/or modeled (and ignored) nonlinearities can be represented by sudden changes in the state. Modeling cardiovascular system (CVS), one of the most fascinating but most complex human physiological systems, with a hybrid approach, is the focus of this chapter. The hybrid property appears naturally in the CVS thanks to the presence of valves which, depending on their state (closed or open), divide the cardiac cycle into four phases. This chapter shows how hybrid models can be used for modeling the CVS. In addition, it describes a preliminary study on the detection of some cardiac anomalies based on the hybrid model and using the standard observer-based approach.

  19. A review of the structure and dynamics of nanoconfined water and ionic liquids via molecular dynamics simulation.

    Science.gov (United States)

    Foroutan, Masumeh; Fatemi, S Mahmood; Esmaeilian, Farshad

    2017-02-01

    During the past decade, the research on fluids in nanoconfined geometries has received considerable attention as a consequence of their wide applications in different fields. Several nanoconfined systems such as water and ionic liquids, together with an equally impressive array of nanoconfining media such as carbon nanotube, graphene and graphene oxide have received increasingly growing interest in the past years. Water is the first system that has been reviewed in this article, due to its important role in transport phenomena in environmental sciences. Water is often considered as a highly nanoconfined system, due to its reduction to a few layers of water molecules between the extended surface of large macromolecules. The second system discussed here is ionic liquids, which have been widely studied in the modern green chemistry movement. Considering the great importance of ionic liquids in industry, and also their oil/water counterpart, nanoconfined ionic liquid system has become an important area of research with many fascinating applications. Furthermore, the method of molecular dynamics simulation is one of the major tools in the theoretical study of water and ionic liquids in nanoconfinement, which increasingly has been joined with experimental procedures. In this way, the choice of water and ionic liquids in nanoconfinement is justified by applying molecular dynamics simulation approaches in this review article.

  20. Hamiltonian dynamics

    CERN Document Server

    Vilasi, Gaetano

    2001-01-01

    This is both a textbook and a monograph. It is partially based on a two-semester course, held by the author for third-year students in physics and mathematics at the University of Salerno, on analytical mechanics, differential geometry, symplectic manifolds and integrable systems. As a textbook, it provides a systematic and self-consistent formulation of Hamiltonian dynamics both in a rigorous coordinate language and in the modern language of differential geometry. It also presents powerful mathematical methods of theoretical physics, especially in gauge theories and general relativity. As a m

  1. Artificial ferroic systems: novel functionality from structure, interactions and dynamics

    International Nuclear Information System (INIS)

    Heyderman, L J; Stamps, R L

    2013-01-01

    Lithographic processing and film growth technologies are continuing to advance, so that it is now possible to create patterned ferroic materials consisting of arrays of sub-1 μm elements with high definition. Some of the most fascinating behaviour of these arrays can be realised by exploiting interactions between the individual elements to create new functionality. The properties of these artificial ferroic systems differ strikingly from those of their constituent components, with novel emergent behaviour arising from the collective dynamics of the interacting elements, which are arranged in specific designs and can be activated by applying magnetic or electric fields. We first focus on artificial spin systems consisting of arrays of dipolar-coupled nanomagnets and, in particular, review the field of artificial spin ice, which demonstrates a wide range of fascinating phenomena arising from the frustration inherent in particular arrangements of nanomagnets, including emergent magnetic monopoles, domains of ordered macrospins, and novel avalanche behaviour. We outline how demagnetisation protocols have been employed as an effective thermal anneal in an attempt to reach the ground state, comment on phenomena that arise in thermally activated systems and discuss strategies for selectively generating specific configurations using applied magnetic fields. We then move on from slow field and temperature driven dynamics to high frequency phenomena, discussing spinwave excitations in the context of magnonic crystals constructed from arrays of patterned magnetic elements. At high frequencies, these arrays are studied in terms of potential applications including magnetic logic, linear and non-linear microwave optics, and fast, efficient switching, and we consider the possibility to create tunable magnonic crystals with artificial spin ice. Finally, we discuss how functional ferroic composites can be incorporated to realise magnetoelectric effects. Specifically, we discuss

  2. Artificial ferroic systems: novel functionality from structure, interactions and dynamics.

    Science.gov (United States)

    Heyderman, L J; Stamps, R L

    2013-09-11

    Lithographic processing and film growth technologies are continuing to advance, so that it is now possible to create patterned ferroic materials consisting of arrays of sub-1 μm elements with high definition. Some of the most fascinating behaviour of these arrays can be realised by exploiting interactions between the individual elements to create new functionality. The properties of these artificial ferroic systems differ strikingly from those of their constituent components, with novel emergent behaviour arising from the collective dynamics of the interacting elements, which are arranged in specific designs and can be activated by applying magnetic or electric fields. We first focus on artificial spin systems consisting of arrays of dipolar-coupled nanomagnets and, in particular, review the field of artificial spin ice, which demonstrates a wide range of fascinating phenomena arising from the frustration inherent in particular arrangements of nanomagnets, including emergent magnetic monopoles, domains of ordered macrospins, and novel avalanche behaviour. We outline how demagnetisation protocols have been employed as an effective thermal anneal in an attempt to reach the ground state, comment on phenomena that arise in thermally activated systems and discuss strategies for selectively generating specific configurations using applied magnetic fields. We then move on from slow field and temperature driven dynamics to high frequency phenomena, discussing spinwave excitations in the context of magnonic crystals constructed from arrays of patterned magnetic elements. At high frequencies, these arrays are studied in terms of potential applications including magnetic logic, linear and non-linear microwave optics, and fast, efficient switching, and we consider the possibility to create tunable magnonic crystals with artificial spin ice. Finally, we discuss how functional ferroic composites can be incorporated to realise magnetoelectric effects. Specifically, we discuss

  3. Dynamics of Tidally Locked, Ultrafast Rotating Atmospheres

    Science.gov (United States)

    Tan, Xianyu; Showman, Adam P.

    2017-10-01

    Tidally locked gas giants, which exhibit a novel regime of day-night thermal forcing and extreme stellar irradiation, are typically in several-day orbits, implying slow rotation and a modest role for rotation in the atmospheric circulation. Nevertheless, there exist a class of gas-giant, highly irradiated objects - brown dwarfs orbiting white dwarfs in extremely tight orbits - whose orbital and hence rotation periods are as short as 1-2 hours. Spitzer phase curves and other observations have already been obtained for this fascinating class of objects, which raise fundamental questions about the role of rotation in controlling the circulation. So far, most modeling studies have investigated rotation periods exceeding a day, as appropriate for typical hot Jupiters. In this work we investigate the dynamics of tidally locked atmospheres in shorter rotation periods down to about two hours. With increasing rotation rate (decreasing rotation period), we show that the width of the equatorial eastward jet decreases, consistent with the narrowing of wave-mean-flow interacting region due to decrease of the equatorial deformation radius. The eastward-shifted equatorial hot spot offset decreases accordingly, and the westward-shifted hot regions poleward of the equatorial jet associated with Rossby gyres become increasingly distinctive. At high latitudes, winds becomes weaker and more geostrophic. The day-night temperature contrast becomes larger due to the stronger influence of rotation. Our simulated atmospheres exhibit small-scale variability, presumably caused by shear instability. Unlike typical hot Jupiters, phase curves of fast-rotating models show an alignment of peak flux to secondary eclipse. Our results have important implications for phase curve observations of brown dwarfs orbiting white dwarfs in ultra tight orbits.

  4. Complex dynamics

    CERN Document Server

    Carleson, Lennart

    1993-01-01

    Complex dynamics is today very much a focus of interest. Though several fine expository articles were available, by P. Blanchard and by M. Yu. Lyubich in particular, until recently there was no single source where students could find the material with proofs. For anyone in our position, gathering and organizing the material required a great deal of work going through preprints and papers and in some cases even finding a proof. We hope that the results of our efforts will be of help to others who plan to learn about complex dynamics and perhaps even lecture. Meanwhile books in the field a. re beginning to appear. The Stony Brook course notes of J. Milnor were particularly welcome and useful. Still we hope that our special emphasis on the analytic side will satisfy a need. This book is a revised and expanded version of notes based on lectures of the first author at UCLA over several \\Vinter Quarters, particularly 1986 and 1990. We owe Chris Bishop a great deal of gratitude for supervising the production of cour...

  5. Population dynamics

    Directory of Open Access Journals (Sweden)

    Cooch, E. G.

    2004-06-01

    Full Text Available Increases or decreases in the size of populations over space and time are, arguably, the motivation for much of pure and applied ecological research. The fundamental model for the dynamics of any population is straightforward: the net change over time in the abundance of some population is the simple difference between the number of additions (individuals entering the population minus the number of subtractions (individuals leaving the population. Of course, the precise nature of the pattern and process of these additions and subtractions is often complex, and population biology is often replete with fairly dense mathematical representations of both processes. While there is no doubt that analysis of such abstract descriptions of populations has been of considerable value in advancing our, there has often existed a palpable discomfort when the ‘beautiful math’ is faced with the often ‘ugly realities’ of empirical data. In some cases, this attempted merger is abandoned altogether, because of the paucity of ‘good empirical data’ with which the theoretician can modify and evaluate more conceptually–based models. In some cases, the lack of ‘data’ is more accurately represented as a lack of robust estimates of one or more parameters. It is in this arena that methods developed to analyze multiple encounter data from individually marked organisms has seen perhaps the greatest advances. These methods have rapidly evolved to facilitate not only estimation of one or more vital rates, critical to population modeling and analysis, but also to allow for direct estimation of both the dynamics of populations (e.g., Pradel, 1996, and factors influencing those dynamics (e.g., Nichols et al., 2000. The interconnections between the various vital rates, their estimation, and incorporation into models, was the general subject of our plenary presentation by Hal Caswell (Caswell & Fujiwara, 2004. Caswell notes that although interest has traditionally

  6. Bile dynamics

    International Nuclear Information System (INIS)

    Harding, L.K.; Donovan, I.A.

    1986-01-01

    The availability of new biliary radiopharamaceutical led to the expectation that the physiology and the pathophysiology of bile would be resolved. Some aspects of the physiology of bile have clarified and it has been shown that nasogastric intubation does not cause bile reflux. Careful analysis of excretion patterns has allowed detection of obstruction of the bile duct after cholecystectomy, and the radiopharmaceuticals have proved helpful in the diagnosis of acute colecystitis. In chronic cholecystitis, however, varying results have been obtained. Information on the incidence and amount of reflux in normal subjects is also confused, since several different techniques have been used with widely varying results. The clinical value of biliary dynamic studies is at present limited in patients with chronic cholecystitis, peptic ulcer, or symptoms suggestive of bile reflux. More data, with appropriate control subjects, is required to identify abnormal reflux, determine its effects, and decide on appropriate treatment

  7. Autonomous Collision-Free Navigation of Microvehicles in Complex and Dynamically Changing Environments.

    Science.gov (United States)

    Li, Tianlong; Chang, Xiaocong; Wu, Zhiguang; Li, Jinxing; Shao, Guangbin; Deng, Xinghong; Qiu, Jianbin; Guo, Bin; Zhang, Guangyu; He, Qiang; Li, Longqiu; Wang, Joseph

    2017-09-26

    Self-propelled micro- and nanoscale robots represent a rapidly emerging and fascinating robotics research area. However, designing autonomous and adaptive control systems for operating micro/nanorobotics in complex and dynamically changing environments, which is a highly demanding feature, is still an unmet challenge. Here we describe a smart microvehicle for precise autonomous navigation in complicated environments and traffic scenarios. The fully autonomous navigation system of the smart microvehicle is composed of a microscope-coupled CCD camera, an artificial intelligence planner, and a magnetic field generator. The microscope-coupled CCD camera provides real-time localization of the chemically powered Janus microsphere vehicle and environmental detection for path planning to generate optimal collision-free routes, while the moving direction of the microrobot toward a reference position is determined by the external electromagnetic torque. Real-time object detection offers adaptive path planning in response to dynamically changing environments. We demonstrate that the autonomous navigation system can guide the vehicle movement in complex patterns, in the presence of dynamically changing obstacles, and in complex biological environments. Such a navigation system for micro/nanoscale vehicles, relying on vision-based close-loop control and path planning, is highly promising for their autonomous operation in complex dynamic settings and unpredictable scenarios expected in a variety of realistic nanoscale scenarios.

  8. Group dynamics.

    Science.gov (United States)

    Scandiffio, A L

    1990-12-01

    Group dynamics play a significant role within any organization, culture, or unit. The important thing to remember with any of these structures is that they are made up of people--people with different ideas, motivations, background, and sometimes different agendas. Most groups, formal or informal, look for a leader in an effort to maintain cohesiveness of the unit. At times, that cultural bond must be developed; once developed, it must be nurtured. There are also times that one of the group no longer finds the culture comfortable and begins to act out behaviorally. It is these times that become trying for the leader as she or he attempts to remain objective when that which was once in the building phase of group cohesiveness starts to fall apart. At all times, the manager must continue to view the employee creating the disturbance as an integral part of the group. It is at this time that it is beneficial to perceive the employee exhibiting problem behaviors as a special employee, as one who needs the benefit of your experience and skills, as one who is still part of the group. It is also during this time that the manager should focus upon her or his own views in the area of power, communication, and the corporate culture of the unit that one has established before attempting to understand another's point of view. Once we understand our own motivation and accept ourselves, it is then that we may move on to offer assistance to another. Once we understand our insecurities recognizing staff dysfunction as a symptom of system dysfunction will not be so threatening to the concept of the manager that we perceive ourselves to be. It takes a secure person to admit that she or he favors staff before deciding to do something to change things. The important thing to know is that it can be done. The favored staff can find a new way of relating to others, the special employee can find new modes of behavior (and even find self-esteem in the process), the group can find new ways

  9. Fluid dynamics

    CERN Document Server

    Ruban, Anatoly I

    This is the first book in a four-part series designed to give a comprehensive and coherent description of Fluid Dynamics, starting with chapters on classical theory suitable for an introductory undergraduate lecture course, and then progressing through more advanced material up to the level of modern research in the field. The present Part 1 consists of four chapters. Chapter 1 begins with a discussion of Continuum Hypothesis, which is followed by an introduction to macroscopic functions, the velocity vector, pressure, density, and enthalpy. We then analyse the forces acting inside a fluid, and deduce the Navier-Stokes equations for incompressible and compressible fluids in Cartesian and curvilinear coordinates. In Chapter 2 we study the properties of a number of flows that are presented by the so-called exact solutions of the Navier-Stokes equations, including the Couette flow between two parallel plates, Hagen-Poiseuille flow through a pipe, and Karman flow above an infinite rotating disk. Chapter 3 is d...

  10. Internet dynamics

    Science.gov (United States)

    Lukose, Rajan Mathew

    The World Wide Web and the Internet are rapidly expanding spaces, of great economic and social significance, which offer an opportunity to study many phenomena, often previously inaccessible, on an unprecedented scale and resolution with relative ease. These phenomena are measurable on the scale of tens of millions of users and hundreds of millions of pages. By virtue of nearly complete electronic mediation, it is possible in principle to observe the time and ``spatial'' evolution of nearly all choices and interactions. This cyber-space therefore provides a view into a number of traditional research questions (from many academic disciplines) and creates its own new phenomena accessible for study. Despite its largely self-organized and dynamic nature, a number of robust quantitative regularities are found in the aggregate statistics of interesting and useful quantities. These regularities can be understood with the help of models that draw on ideas from statistical physics as well as other fields such as economics, psychology and decision theory. This thesis develops models that can account for regularities found in the statistics of Internet congestion and user surfing patterns and discusses some practical consequences. practical consequences.

  11. On the hydration of subnanometric antifouling organosilane adlayers: a molecular dynamics simulation.

    Science.gov (United States)

    Sheikh, Sonia; Blaszykowski, Christophe; Nolan, Robert; Thompson, Damien; Thompson, Michael

    2015-01-01

    The connection between antifouling and surface hydration is a fascinating but daunting question to answer. Herein, we use molecular dynamics (MD) computer simulations to gain further insight into the role of surface functionalities in the molecular-level structuration of water (surface kosmotropicity)--within and atop subnanometric organosilane adlayers that were shown in previous experimental work to display varied antifouling behavior. Our simulations support the hypothesized intimate link between surface hydration and antifouling, in particular the importance of both internal and interfacial hydrophilicity and kosmotropicity. The antifouling mechanism is also discussed in terms of surface dehydration energy and water dynamicity (lability and mobility), notably the crucial requirement for clustered water molecules to remain tightly bound for extensive periods of time--i.e. exhibit slow exchange dynamics. A substrate effect on surface hydration, which would also participate in endowing antifouling adlayers with hydrogel-like characteristics, is also proposed. In contrast, the role of adlayer flexibility, if any, is assigned a secondary role in these ultrathin structures made of short building blocks. The conclusions from this work are well in line with those previously drawn in the literature. Copyright © 2014 Elsevier Inc. All rights reserved.

  12. Relativistic stellar dynamics

    International Nuclear Information System (INIS)

    Contopoulos, G.

    1983-01-01

    In this paper, three main areas of relativistic stellar dynamics are reviewed: (a) The dynamics of clusters, or nuclei of galaxies, of very high density; (b) The dynamics of systems containing a massive black hole; and (c) The dynamics of particles (and photons) in an expanding Universe. The emphasis is on the use of orbit perturbations. (Auth.)

  13. Principles of magnetoplasma dynamics

    International Nuclear Information System (INIS)

    Woods, L.C.

    1987-01-01

    A self-contained account is given of magnetoplasma dynamics covering fluid dynamics, thermodynamics, kinetic theory of gases, particle dynamics and electromagnetism. The six chapter headings are, basic concepts, magnetohydrodynamics, dynamics of charged particles, transport in a magnetoplasma, magnetoplasma shock waves, and transport in tokamaks. There are 231 references. (U.K.)

  14. Fundamentals of structural dynamics

    CERN Document Server

    Craig, Roy R

    2006-01-01

    From theory and fundamentals to the latest advances in computational and experimental modal analysis, this is the definitive, updated reference on structural dynamics.This edition updates Professor Craig's classic introduction to structural dynamics, which has been an invaluable resource for practicing engineers and a textbook for undergraduate and graduate courses in vibrations and/or structural dynamics. Along with comprehensive coverage of structural dynamics fundamentals, finite-element-based computational methods, and dynamic testing methods, this Second Edition includes new and e

  15. Dynamic light scattering. Observation of polymer dynamics

    International Nuclear Information System (INIS)

    Hiroi, Takashi

    2015-01-01

    Dynamic light scattering is a technique to measure properties of polymer solutions such as size distribution. Principle of dynamic light scattering is briefly explained. Sometime dynamic light scattering is regarded as the observation of Doppler shift of scattered light. First, the difficulty for the direct observation of this Doppler shift is mentioned. Then the measurement by using a time correlation function is introduced. Measuring techniques for dynamic light scattering are also introduced. In addition to homodyne and heterodyne detection techniques, the technique called partial heterodyne method is also introduced. This technique is useful for the analysis of nonergodic medium such as polymer gels. Then the application of this technique to condensed suspension is briefly reviewed. As one of the examples, a dynamic light scattering microscope is introduced. By using this apparatus, we can measure the concentration dependence of the size distribution of polymer solutions. (author)

  16. Dynamic statistical information theory

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    In recent years we extended Shannon static statistical information theory to dynamic processes and established a Shannon dynamic statistical information theory, whose core is the evolution law of dynamic entropy and dynamic information. We also proposed a corresponding Boltzmman dynamic statistical information theory. Based on the fact that the state variable evolution equation of respective dynamic systems, i.e. Fokker-Planck equation and Liouville diffusion equation can be regarded as their information symbol evolution equation, we derived the nonlinear evolution equations of Shannon dynamic entropy density and dynamic information density and the nonlinear evolution equations of Boltzmann dynamic entropy density and dynamic information density, that describe respectively the evolution law of dynamic entropy and dynamic information. The evolution equations of these two kinds of dynamic entropies and dynamic informations show in unison that the time rate of change of dynamic entropy densities is caused by their drift, diffusion and production in state variable space inside the systems and coordinate space in the transmission processes; and that the time rate of change of dynamic information densities originates from their drift, diffusion and dissipation in state variable space inside the systems and coordinate space in the transmission processes. Entropy and information have been combined with the state and its law of motion of the systems. Furthermore we presented the formulas of two kinds of entropy production rates and information dissipation rates, the expressions of two kinds of drift information flows and diffusion information flows. We proved that two kinds of information dissipation rates (or the decrease rates of the total information) were equal to their corresponding entropy production rates (or the increase rates of the total entropy) in the same dynamic system. We obtained the formulas of two kinds of dynamic mutual informations and dynamic channel

  17. Structure, Reactivity and Dynamics

    Indian Academy of Sciences (India)

    Understanding structure, reactivity and dynamics is the core issue in chemical ... functional theory (DFT) calculations, molecular dynamics (MD) simulations, light- ... between water and protein oxygen atoms, the superionic conductors which ...

  18. Modeling dynamic swarms

    KAUST Repository

    Ghanem, Bernard; Ahuja, Narendra

    2013-01-01

    This paper proposes the problem of modeling video sequences of dynamic swarms (DSs). We define a DS as a large layout of stochastically repetitive spatial configurations of dynamic objects (swarm elements) whose motions exhibit local spatiotemporal

  19. News Education: Physics Education Networks meeting has global scale Competition: Competition seeks the next Brian Cox Experiment: New measurement of neutrino time-of-flight consistent with the speed of light Event: A day for all those who teach physics Conference: Students attend first Anglo-Japanese international science conference Celebration: Will 2015 be the 'Year of Light'? Teachers: Challenging our intuition in spectacular fashion: the fascinating world of quantum physics awaits Research: Science sharpens up sport Learning: Kittinger and Baumgartner: on a mission to the edge of space International: London International Youth Science Forum calls for leading young scientists Competition: Physics paralympian challenge needs inquisitive, analytical, artistic and eloquent pupils Forthcoming events

    Science.gov (United States)

    2012-05-01

    Education: Physics Education Networks meeting has global scale Competition: Competition seeks the next Brian Cox Experiment: New measurement of neutrino time-of-flight consistent with the speed of light Event: A day for all those who teach physics Conference: Students attend first Anglo-Japanese international science conference Celebration: Will 2015 be the 'Year of Light'? Teachers: Challenging our intuition in spectacular fashion: the fascinating world of quantum physics awaits Research: Science sharpens up sport Learning: Kittinger and Baumgartner: on a mission to the edge of space International: London International Youth Science Forum calls for leading young scientists Competition: Physics paralympian challenge needs inquisitive, analytical, artistic and eloquent pupils Forthcoming events

  20. Spaces of Dynamical Systems

    CERN Document Server

    Pilyugin, Sergei Yu

    2012-01-01

    Dynamical systems are abundant in theoretical physics and engineering. Their understanding, with sufficient mathematical rigor, is vital to solving many problems. This work conveys the modern theory of dynamical systems in a didactically developed fashion.In addition to topological dynamics, structural stability and chaotic dynamics, also generic properties and pseudotrajectories are covered, as well as nonlinearity. The author is an experienced book writer and his work is based on years of teaching.

  1. Visualizing electron dynamics in organic materials: Charge transport through molecules and angular resolved photoemission

    Science.gov (United States)

    Kümmel, Stephan

    Being able to visualize the dynamics of electrons in organic materials is a fascinating perspective. Simulations based on time-dependent density functional theory allow to realize this hope, as they visualize the flow of charge through molecular structures in real-space and real-time. We here present results on two fundamental processes: Photoemission from organic semiconductor molecules and charge transport through molecular structures. In the first part we demonstrate that angular resolved photoemission intensities - from both theory and experiment - can often be interpreted as a visualization of molecular orbitals. However, counter-intuitive quantum-mechanical electron dynamics such as emission perpendicular to the direction of the electrical field can substantially alter the picture, adding surprising features to the molecular orbital interpretation. In a second study we calculate the flow of charge through conjugated molecules. The calculations show in real time how breaks in the conjugation can lead to a local buildup of charge and the formation of local electrical dipoles. These can interact with neighboring molecular chains. As a consequence, collections of ''molecular electrical wires'' can show distinctly different characteristics than ''classical electrical wires''. German Science Foundation GRK 1640.

  2. Dynamics of Media Attention

    NARCIS (Netherlands)

    Traag, V.A.; Reinanda, R.; Hicks, J.; van Klinken, G.; Aziz-Alaoui, M.A.; Bertelle, C.; Liu, X.; Olivier, D.

    2014-01-01

    Studies of human attention dynamics analyses how attention is focused on specific topics, issues or people. In online social media, there are clear signs of exogenous shocks, bursty dynamics, and an exponential or powerlaw lifetime distribution. We here analyse the attention dynamics of traditional

  3. Intramolecular and nonlinear dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Davis, M.J. [Argonne National Laboratory, IL (United States)

    1993-12-01

    Research in this program focuses on three interconnected areas. The first involves the study of intramolecular dynamics, particularly of highly excited systems. The second area involves the use of nonlinear dynamics as a tool for the study of molecular dynamics and complex kinetics. The third area is the study of the classical/quantum correspondence for highly excited systems, particularly systems exhibiting classical chaos.

  4. PREFACE: Dynamics of wetting Dynamics of wetting

    Science.gov (United States)

    Grest, Gary S.; Oshanin, Gleb; Webb, Edmund B., III

    2009-11-01

    Capillary phenomena associated with fluids wetting other condensed matter phases have drawn great scientific interest for hundreds of years; consider the recent bicentennial celebration of Thomas Young's paper on equilibrium contact angles, describing the geometric shape assumed near a three phase contact line in terms of the relevant surface energies of the constituent phases [1]. Indeed, nearly a century has passed since the seminal papers of Lucas and Washburn, describing dynamics of capillary imbibition [2, 3]. While it is generally appreciated that dynamics of fluid wetting processes are determined by the degree to which a system is out of capillary equilibrium, myriad complications exist that challenge the fundamental understanding of dynamic capillary phenomena. The topic has gathered much interest from recent Nobel laureate Pierre-Gilles de Gennes, who provided a seminal review of relevant dissipation mechanisms for fluid droplets spreading on solid surfaces [4] Although much about the dynamics of wetting has been revealed, much remains to be learned and intrinsic technological and fundamental interest in the topic drives continuing high levels of research activity. This is enabled partly by improved experimental capabilities for resolving wetting processes at increasingly finer temporal, spatial, and chemical resolution. Additionally, dynamic wetting research advances via higher fidelity computational modeling capabilities, which drive more highly refined theory development. The significance of this topic both fundamentally and technologically has resulted in a number of reviews of research activity in wetting dynamics. One recent example addresses the evaluation of existing wetting dynamics theories from an experimentalist's perspective [5]. A Current Opinion issue was recently dedicated to high temperature capillarity, including dynamics of high temperature spreading [6]. New educational tools have recently emerged for providing instruction in wetting

  5. Application of the Real-Time Time-Dependent Density Functional Theory to Excited-State Dynamics of Molecules and 2D Materials

    Science.gov (United States)

    Miyamoto, Yoshiyuki; Rubio, Angel

    2018-04-01

    We review our recent developments in the ab initio simulation of excited-state dynamics within the framework of time-dependent density functional theory (TDDFT). Our targets range from molecules to 2D materials, although the methods are general and can be applied to any other finite and periodic systems. We discuss examples of excited-state dynamics obtained by real-time TDDFT coupled with molecular dynamics (MD) and the Ehrenfest approximation, including photoisomerization in molecules, photoenhancement of the weak interatomic attraction of noble gas atoms, photoenhancement of the weak interlayer interaction of 2D materials, pulse-laser-induced local bond breaking of adsorbed atoms on 2D sheets, modulation of UV light intensity by graphene nanoribbons at terahertz frequencies, and collision of high-speed ions with the 2D material to simulate the images taken by He ion microscopy. We illustrate how the real-time TDDFT approach is useful for predicting and understanding non-equilibrium dynamics in condensed matter. We also discuss recent developments that address the excited-state dynamics of systems out of equilibrium and future challenges in this fascinating field of research.

  6. Dynamic link: user's manual

    International Nuclear Information System (INIS)

    Harada, Hiroo; Asai, Kiyoshi; Kihara, Kazuhisa.

    1981-09-01

    The purpose of dynamic link facility is to link a load module dynamically only when it is used in execution time. The facility is very useful for development, execution and maintenance of a large scale computer program which is too big to be saved as one load module in main memory, or it is poor economy to save it due to many unused subroutines depending on an input. It is also useful for standardization and common utilization of programs. Standard usage of dynamic link facility of FACOM M-200 computer system, a software tool which analyzes the effect of dynamic link facility and application of dynamic link to nuclear codes are described. (author)

  7. Deformed Materials: Towards a Theory of Materials Morphology Dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Sethna, James P [Laboratory of Atomic and Solid State Physics, Cornell University

    2017-06-28

    This grant supported work on the response of crystals to external stress. Our primary work described how disordered structural materials break in two (statistical models of fracture in disordered materials), studied models of deformation bursts (avalanches) that mediate deformation on the microscale, and developed continuum dislocation dynamics models for plastic deformation (as when scooping ice cream bends a spoon, Fig. 9). Glass is brittle -- it breaks with almost atomically smooth fracture surfaces. Many metals are ductile -- when they break, the fracture surface is locally sheared and stretched, and it is this damage that makes them hard to break. Bone and seashells are made of brittle material, but they are strong because they are disordered -- lots of little cracks form as they are sheared and near the fracture surface, diluting the external force. We have studied materials like bone and seashells using simulations, mathematical tools, and statistical mechanics models from physics. In particular, we studied the extreme values of fracture strengths (how likely will a beam in a bridge break far below its design strength), and found that the traditional engineering tools could be improved greatly. We also studied fascinating crackling-noise precursors -- systems which formed microcracks of a broad range of sizes before they broke. Ductile metals under stress undergo irreversible plastic deformation -- the planes of atoms must slide across one another (through the motion of dislocations) to change the overall shape in response to the external force. Microscopically, the dislocations in crystals move in bursts of a broad range of sizes (termed 'avalanches' in the statistical mechanics community, whose motion is deemed 'crackling noise'). In this grant period, we resolved a longstanding mystery about the average shape of avalanches of fixed duration (using tools related to an emergent scale invariance), we developed the fundamental theory

  8. What can we learn from the dynamics of entanglement and quantum discord in the Tavis-Cummings model?

    Science.gov (United States)

    Restrepo, Juliana; Rodriguez, Boris A.

    We revisit the problem of the dynamics of quantum correlations in the exact Tavis-Cummings model. We show that many of the dynamical features of quantum discord attributed to dissipation are already present in the exact framework and are due to the well known non-linearities in the model and to the choice of initial conditions. Through a comprehensive analysis, supported by explicit analytical calculations, we find that the dynamics of entanglement and quantum discord are far from being trivial or intuitive. In this context, we find states that are indistinguishable from the point of view of entanglement and distinguishable from the point of view of quantum discord, states where the two quantifiers give opposite information and states where they give roughly the same information about correlations at a certain time. Depending on the initial conditions, this model exhibits a fascinating range of phenomena that can be used for experimental purposes such as: Robust states against change of manifold or dissipation, tunable entanglement states and states with a counterintuitive sudden birth as the number of photons increase. We furthermore propose an experiment called quantum discord gates where discord is zero or non-zero depending on the number of photons. This work was supported by the Vicerrectoria de Investigacion of the Universidad Antonio Narino, Colombia under Project Number 20141031 and by the Departamento Administrativo de Ciencia, Tecnologia e Innovacion (COLCIENCIAS) of Colombia under Grant Number.

  9. Complexity and Dynamical Depth

    Directory of Open Access Journals (Sweden)

    Terrence Deacon

    2014-07-01

    Full Text Available We argue that a critical difference distinguishing machines from organisms and computers from brains is not complexity in a structural sense, but a difference in dynamical organization that is not well accounted for by current complexity measures. We propose a measure of the complexity of a system that is largely orthogonal to computational, information theoretic, or thermodynamic conceptions of structural complexity. What we call a system’s dynamical depth is a separate dimension of system complexity that measures the degree to which it exhibits discrete levels of nonlinear dynamical organization in which successive levels are distinguished by local entropy reduction and constraint generation. A system with greater dynamical depth than another consists of a greater number of such nested dynamical levels. Thus, a mechanical or linear thermodynamic system has less dynamical depth than an inorganic self-organized system, which has less dynamical depth than a living system. Including an assessment of dynamical depth can provide a more precise and systematic account of the fundamental difference between inorganic systems (low dynamical depth and living systems (high dynamical depth, irrespective of the number of their parts and the causal relations between them.

  10. Dynamic and quasi-dynamic multileaf collimation

    International Nuclear Information System (INIS)

    Bortfeld, T.

    1995-01-01

    Several recent investigations deal with the problem of how to produce arbitrary two-dimensional x-ray fluence distributions by means of a multileaf collimator (MLC), an approach, which could be called multileaf modulation. The goal of this approach is to facilitate the delivery of compensated or intensity-modulated fields. The present work gives an overview of these developments. The hardware requirements on MLCs for this special application are specified. Most commercially available MLCs fulfill these requirement sufficiently, however, the MLC control software is generally not capable of controlling an MLC dynamically. There is also the question of how to verify the dynamic movement of the leaves. Some minimum requirements on a control software suitable for application in clinical practice are therefore specified. An alternative, the stepwise or 'quasi-dynamic' movement of the MLC-leaves, is also discussed with respect to practicality. In this case the control is easier, but the demands on the stability of the accelerator for small dose deliveries are higher. Nevertheless, it can be expected that, for reasons of ease of control and verification, the quasi-dynamic technique will become the method of choice in the near future, while the slightly more effective fully dynamic technique will become available later in the future. In any case, multileaf modulation is an interesting and important alternative to the tomotherapy-concept

  11. Synchronization dynamics of two different dynamical systems

    International Nuclear Information System (INIS)

    Luo, Albert C.J.; Min Fuhong

    2011-01-01

    Highlights: → Synchronization dynamics of two distinct dynamical systems. → Synchronization, de-synchronization and instantaneous synchronization. → A controlled pendulum synchronizing with the Duffing oscillator. → Synchronization invariant set. → Synchronization parameter map. - Abstract: In this paper, synchronization dynamics of two different dynamical systems is investigated through the theory of discontinuous dynamical systems. The necessary and sufficient conditions for the synchronization, de-synchronization and instantaneous synchronization (penetration or grazing) are presented. Using such a synchronization theory, the synchronization of a controlled pendulum with the Duffing oscillator is systematically discussed as a sampled problem, and the corresponding analytical conditions for the synchronization are presented. The synchronization parameter study is carried out for a better understanding of synchronization characteristics of the controlled pendulum and the Duffing oscillator. Finally, the partial and full synchronizations of the controlled pendulum with periodic and chaotic motions are presented to illustrate the analytical conditions. The synchronization of the Duffing oscillator and pendulum are investigated in order to show the usefulness and efficiency of the methodology in this paper. The synchronization invariant domain is obtained. The technique presented in this paper should have a wide spectrum of applications in engineering. For example, this technique can be applied to the maneuvering target tracking, and the others.

  12. Dynamic Boiler Performance

    DEFF Research Database (Denmark)

    Sørensen, Kim

    Traditionally, boilers have been designed mainly focussing on the static operation of the plant. The dynamic capability has been given lower priority and the analysis has typically been limited to assuring that the plant was not over-stressed due to large temperature gradients. New possibilities...... developed. Analyzing boilers for dynamic operation gives rise to a number of opposing aims: shrinking and swelling, steam quality, stress levels, control system/philosophy, pressurization etc. Common for these opposing aims is that an optimum can be found for selected operation conditions. The framework has...... for buying and selling energy has increased the focus on the dynamic operation capability, efciency, emissions etc. For optimizing the design of boilers for dynamic operation a quantication of the dynamic capability is needed. A framework for optimizing design of boilers for dynamic operation has been...

  13. Nonlinear dynamics and astrophysics

    International Nuclear Information System (INIS)

    Vallejo, J. C.; Sanjuan, M. A. F.

    2000-01-01

    Concepts and techniques from Nonlinear Dynamics, also known as Chaos Theory, have been applied successfully to several astrophysical fields such as orbital motion, time series analysis or galactic dynamics, providing answers to old questions but also opening a few new ones. Some of these topics are described in this review article, showing the basis of Nonlinear Dynamics, and how it is applied in Astrophysics. (Author)

  14. Record Statistics and Dynamics

    DEFF Research Database (Denmark)

    Sibani, Paolo; Jensen, Henrik J.

    2009-01-01

    with independent random increments. The term record dynamics covers the rather new idea that records may, in special situations, have measurable dynamical consequences. The approach applies to the aging dynamics of glasses and other systems with multiple metastable states. The basic idea is that record sizes...... fluctuations of e. g. the energy are able to push the system past some sort of ‘edge of stability’, inducing irreversible configurational changes, whose statistics then closely follows the statistics of record fluctuations....

  15. Dynamics of unstable systems

    International Nuclear Information System (INIS)

    Posch, H.A.; Narnhofer, H.; Thirring, W.

    1990-01-01

    We study the dynamics of classical particles interacting with attractive Gaussian potentials. This system is thermodynamically not stable and exhibits negative specific heat. The results of the computer simulation of the dynamics are discussed in comparison with various theories. In particular, we find that the condensed phase is a stationary solution of the Vlasov equation, but the Vlasov dynamics cannot describe the collapse. 14 refs., 1 tab., 11 figs. (Authors)

  16. Dynamical principles in neuroscience

    International Nuclear Information System (INIS)

    Rabinovich, Mikhail I.; Varona, Pablo; Selverston, Allen I.; Abarbanel, Henry D. I.

    2006-01-01

    Dynamical modeling of neural systems and brain functions has a history of success over the last half century. This includes, for example, the explanation and prediction of some features of neural rhythmic behaviors. Many interesting dynamical models of learning and memory based on physiological experiments have been suggested over the last two decades. Dynamical models even of consciousness now exist. Usually these models and results are based on traditional approaches and paradigms of nonlinear dynamics including dynamical chaos. Neural systems are, however, an unusual subject for nonlinear dynamics for several reasons: (i) Even the simplest neural network, with only a few neurons and synaptic connections, has an enormous number of variables and control parameters. These make neural systems adaptive and flexible, and are critical to their biological function. (ii) In contrast to traditional physical systems described by well-known basic principles, first principles governing the dynamics of neural systems are unknown. (iii) Many different neural systems exhibit similar dynamics despite having different architectures and different levels of complexity. (iv) The network architecture and connection strengths are usually not known in detail and therefore the dynamical analysis must, in some sense, be probabilistic. (v) Since nervous systems are able to organize behavior based on sensory inputs, the dynamical modeling of these systems has to explain the transformation of temporal information into combinatorial or combinatorial-temporal codes, and vice versa, for memory and recognition. In this review these problems are discussed in the context of addressing the stimulating questions: What can neuroscience learn from nonlinear dynamics, and what can nonlinear dynamics learn from neuroscience?

  17. Dynamical principles in neuroscience

    Science.gov (United States)

    Rabinovich, Mikhail I.; Varona, Pablo; Selverston, Allen I.; Abarbanel, Henry D. I.

    2006-10-01

    Dynamical modeling of neural systems and brain functions has a history of success over the last half century. This includes, for example, the explanation and prediction of some features of neural rhythmic behaviors. Many interesting dynamical models of learning and memory based on physiological experiments have been suggested over the last two decades. Dynamical models even of consciousness now exist. Usually these models and results are based on traditional approaches and paradigms of nonlinear dynamics including dynamical chaos. Neural systems are, however, an unusual subject for nonlinear dynamics for several reasons: (i) Even the simplest neural network, with only a few neurons and synaptic connections, has an enormous number of variables and control parameters. These make neural systems adaptive and flexible, and are critical to their biological function. (ii) In contrast to traditional physical systems described by well-known basic principles, first principles governing the dynamics of neural systems are unknown. (iii) Many different neural systems exhibit similar dynamics despite having different architectures and different levels of complexity. (iv) The network architecture and connection strengths are usually not known in detail and therefore the dynamical analysis must, in some sense, be probabilistic. (v) Since nervous systems are able to organize behavior based on sensory inputs, the dynamical modeling of these systems has to explain the transformation of temporal information into combinatorial or combinatorial-temporal codes, and vice versa, for memory and recognition. In this review these problems are discussed in the context of addressing the stimulating questions: What can neuroscience learn from nonlinear dynamics, and what can nonlinear dynamics learn from neuroscience?

  18. Computational Fluid Dynamics

    International Nuclear Information System (INIS)

    Myeong, Hyeon Guk

    1999-06-01

    This book deals with computational fluid dynamics with basic and history of numerical fluid dynamics, introduction of finite volume method using one-dimensional heat conduction equation, solution of two-dimensional heat conduction equation, solution of Navier-Stokes equation, fluid with heat transport, turbulent flow and turbulent model, Navier-Stokes solution by generalized coordinate system such as coordinate conversion, conversion of basic equation, program and example of calculation, application of abnormal problem and high speed solution of numerical fluid dynamics.

  19. Nonlinear waves and pattern dynamics

    CERN Document Server

    Pelinovsky, Efim; Mutabazi, Innocent

    2018-01-01

    This book addresses the fascinating phenomena associated with nonlinear waves and spatio-temporal patterns. These appear almost everywhere in nature from sand bed forms to brain patterns, and yet their understanding still presents fundamental scientific challenges. The reader will learn here, in particular, about the current state-of-the art and new results in: Nonlinear water waves: resonance, solitons, focusing, Bose-Einstein condensation, as well as and their relevance for the sea environment (sea-wind interaction, sand bed forms, fiber clustering) Pattern formation in non-equilibrium media: soap films, chimera patterns in oscillating media, viscoelastic Couette-Taylor flow, flow in the wake behind a heated cylinder, other pattern formation. The editors and authors dedicate this book to the memory of Alexander Ezersky, Professor of Fluid Mechanics at the University of Caen Normandie (France) from September 2007 to July 2016. Before 2007, he had served as a Senior Scientist at the Institute of Applied Physi...

  20. Double dynamic scaling in human communication dynamics

    Science.gov (United States)

    Wang, Shengfeng; Feng, Xin; Wu, Ye; Xiao, Jinhua

    2017-05-01

    In the last decades, human behavior has been deeply understanding owing to the huge quantities data of human behavior available for study. The main finding in human dynamics shows that temporal processes consist of high-activity bursty intervals alternating with long low-activity periods. A model, assuming the initiator of bursty follow a Poisson process, is widely used in the modeling of human behavior. Here, we provide further evidence for the hypothesis that different bursty intervals are independent. Furthermore, we introduce a special threshold to quantitatively distinguish the time scales of complex dynamics based on the hypothesis. Our results suggest that human communication behavior is a composite process of double dynamics with midrange memory length. The method for calculating memory length would enhance the performance of many sequence-dependent systems, such as server operation and topic identification.

  1. Introduction to dynamic programming

    CERN Document Server

    Cooper, Leon; Rodin, E Y

    1981-01-01

    Introduction to Dynamic Programming provides information pertinent to the fundamental aspects of dynamic programming. This book considers problems that can be quantitatively formulated and deals with mathematical models of situations or phenomena that exists in the real world.Organized into 10 chapters, this book begins with an overview of the fundamental components of any mathematical optimization model. This text then presents the details of the application of dynamic programming to variational problems. Other chapters consider the application of dynamic programming to inventory theory, Mark

  2. Essential dynamics and relativity

    CERN Document Server

    O'Donnell, Peter J

    2014-01-01

    Essential Dynamics & Relativity provides students with an introduction to the core aspects of dynamics and special relativity. The author reiterates important ideas and terms throughout and covers concepts that are often missing from other textbooks at this level. He also places each topic within the wider constructs of the theory, without jumping from topic to topic to illustrate a point.The first section of the book focuses on dynamics, discussing the basic aspects of single particle motion and analyzing the motion of multi-particle systems. The book also explains the dynamical behavior of b

  3. Dynamical Systems Conference

    CERN Document Server

    Gils, S; Hoveijn, I; Takens, F; Nonlinear Dynamical Systems and Chaos

    1996-01-01

    Symmetries in dynamical systems, "KAM theory and other perturbation theories", "Infinite dimensional systems", "Time series analysis" and "Numerical continuation and bifurcation analysis" were the main topics of the December 1995 Dynamical Systems Conference held in Groningen in honour of Johann Bernoulli. They now form the core of this work which seeks to present the state of the art in various branches of the theory of dynamical systems. A number of articles have a survey character whereas others deal with recent results in current research. It contains interesting material for all members of the dynamical systems community, ranging from geometric and analytic aspects from a mathematical point of view to applications in various sciences.

  4. Engineering quantum dynamics

    International Nuclear Information System (INIS)

    Lloyd, Seth; Viola, Lorenza

    2002-01-01

    The ability to perform measurements on a quantum system, combined with the ability to feed back the measurement results via coherent control, allows one to control the system to follow any desired coherent or incoherent quantum dynamics. Such universal dynamical control can be achieved, in principle, through the repeated application of only two coherent control operations and a simple 'Yes-No' measurement. As a consequence, a quantum computer can simulate an arbitrary open-system dynamics using just one qubit more than required to simulate closed-system dynamics

  5. Modern fluid dynamics

    CERN Document Server

    Kleinstreuer, Clement

    2018-01-01

    Modern Fluid Dynamics, Second Edition provides up-to-date coverage of intermediate and advanced fluids topics. The text emphasizes fundamentals and applications, supported by worked examples and case studies. Scale analysis, non-Newtonian fluid flow, surface coating, convection heat transfer, lubrication, fluid-particle dynamics, microfluidics, entropy generation, and fluid-structure interactions are among the topics covered. Part A presents fluids principles, and prepares readers for the applications of fluid dynamics covered in Part B, which includes computer simulations and project writing. A review of the engineering math needed for fluid dynamics is included in an appendix.

  6. Control of dynamical localization

    International Nuclear Information System (INIS)

    Gong Jiangbin; Woerner, Hans Jakob; Brumer, Paul

    2003-01-01

    Control over the quantum dynamics of chaotic kicked rotor systems is demonstrated. Specifically, control over a number of quantum coherent phenomena is achieved by a simple modification of the kicking field. These include the enhancement of the dynamical localization length, the introduction of classical anomalous diffusion assisted control for systems far from the semiclassical regime, and the observation of a variety of strongly nonexponential line shapes for dynamical localization. The results provide excellent examples of controlled quantum dynamics in a system that is classically chaotic and offer opportunities to explore quantum fluctuations and correlations in quantum chaos

  7. Nonlinear dynamics and complexity

    CERN Document Server

    Luo, Albert; Fu, Xilin

    2014-01-01

    This important collection presents recent advances in nonlinear dynamics including analytical solutions, chaos in Hamiltonian systems, time-delay, uncertainty, and bio-network dynamics. Nonlinear Dynamics and Complexity equips readers to appreciate this increasingly main-stream approach to understanding complex phenomena in nonlinear systems as they are examined in a broad array of disciplines. The book facilitates a better understanding of the mechanisms and phenomena in nonlinear dynamics and develops the corresponding mathematical theory to apply nonlinear design to practical engineering.

  8. Structural Dynamics Laboratory (SDL)

    Data.gov (United States)

    Federal Laboratory Consortium — Structural dynamic testing is performed to verify the survivability of a component or assembly when exposed to vibration stress screening, or a controlled simulation...

  9. Vegetation dynamics and dynamic vegetation science

    NARCIS (Netherlands)

    Van der Maarel, E

    1996-01-01

    his contribution presents a review of the development of the study of vegetation dynamics since 1979, in the framework of a jubilee meeting on progress in the study of vegetation. However, an exhaustive review is both impossible and unnecessary. It is impossible within the few pages available

  10. Dynamic defense workshop :

    Energy Technology Data Exchange (ETDEWEB)

    Crosby, Sean Michael; Doak, Justin E.; Haas, Jason Juedes.; Helinski, Ryan; Lamb, Christopher C.

    2013-02-01

    On September 5th and 6th, 2012, the Dynamic Defense Workshop: From Research to Practice brought together researchers from academia, industry, and Sandia with the goals of increasing collaboration between Sandia National Laboratories and external organizations, de ning and un- derstanding dynamic, or moving target, defense concepts and directions, and gaining a greater understanding of the state of the art for dynamic defense. Through the workshop, we broadened and re ned our de nition and understanding, identi ed new approaches to inherent challenges, and de ned principles of dynamic defense. Half of the workshop was devoted to presentations of current state-of-the-art work. Presentation topics included areas such as the failure of current defenses, threats, techniques, goals of dynamic defense, theory, foundations of dynamic defense, future directions and open research questions related to dynamic defense. The remainder of the workshop was discussion, which was broken down into sessions on de ning challenges, applications to host or mobile environments, applications to enterprise network environments, exploring research and operational taxonomies, and determining how to apply scienti c rigor to and investigating the eld of dynamic defense.

  11. Structural Dynamics, Vol. 9

    DEFF Research Database (Denmark)

    Nielsen, Søren R.K.

    This book has been prepared for the course on Computational Dynamics given at the 8th semester at the structural program in civil engineering at Aalborg University.......This book has been prepared for the course on Computational Dynamics given at the 8th semester at the structural program in civil engineering at Aalborg University....

  12. Nonlinear dynamics in Nuclotron

    International Nuclear Information System (INIS)

    Dinev, D.

    1997-01-01

    The paper represents an extensive study of the nonlinear beam dynamics in the Nuclotron. Chromatic effects, including the dependence of the betatron tunes on the amplitude, and chromatic perturbations have been investigated taking into account the measured field imperfections. Beam distortion, smear, dynamic aperture and nonlinear acceptance have been calculated for different particle energies and betatron tunes

  13. Dynamic Shannon Coding

    OpenAIRE

    Gagie, Travis

    2005-01-01

    We present a new algorithm for dynamic prefix-free coding, based on Shannon coding. We give a simple analysis and prove a better upper bound on the length of the encoding produced than the corresponding bound for dynamic Huffman coding. We show how our algorithm can be modified for efficient length-restricted coding, alphabetic coding and coding with unequal letter costs.

  14. Dynamic paradigm of turbulence

    International Nuclear Information System (INIS)

    Mukhamedov, Alfred M.

    2006-01-01

    In this paper a dynamic paradigm of turbulence is proposed. The basic idea consists in the novel definition of chaotic structure given with the help of Pfaff system of PDE associated with the turbulent dynamics. A methodological analysis of the new and the former paradigm is produced

  15. Dynamic Capabilities and Performance

    DEFF Research Database (Denmark)

    Wilden, Ralf; Gudergan, Siegfried P.; Nielsen, Bo Bernhard

    2013-01-01

    are contingent on the competitive intensity faced by firms. Our findings demonstrate the performance effects of internal alignment between organizational structure and dynamic capabilities, as well as the external fit of dynamic capabilities with competitive intensity. We outline the advantages of PLS...

  16. Dynamic Gaming Platform (DGP)

    Science.gov (United States)

    2009-04-01

    GAMING PLATFORM (DGP) Lockheed Martin Corporation...YYYY) APR 09 2. REPORT TYPE Final 3. DATES COVERED (From - To) Jul 07 – Mar 09 4. TITLE AND SUBTITLE DYNAMIC GAMING PLATFORM (DGP) 5a...CMU Carnegie Mellon University DGP Dynamic Gaming Platform GA Genetic Algorithm IARPA Intelligence Advanced Research Projects Activity LM ATL Lockheed Martin Advanced Technology Laboratories PAINT ProActive INTelligence

  17. Dynamic covalent surfactants

    NARCIS (Netherlands)

    Minkenberg, C.B.

    2012-01-01

    In this thesis the development of surfactant aggregates with fast exchange dynamics between the aggregated and non-aggregated state is described. Dynamic surfactant exchange plays an important role in natural systems, for instance in cell signaling, cell division, and uptake and release of cargo.

  18. Dynamics on the Circle

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 8; Issue 11. Dynamics on the Circle - Interval Dynamics and Rotation Number. Siddhartha Gadgil. General Article Volume 8 Issue 11 November 2003 pp 25-36. Fulltext. Click here to view fulltext PDF. Permanent link:

  19. Dynamic Speaking Assessments

    Science.gov (United States)

    Hill, Kent; Sabet, Mehran

    2009-01-01

    This article describes an attempt to adopt dynamic assessment (DA) methods in classroom speaking assessments. The study reported in this article focused on four particular applications of dynamic speaking assessment (DSA). The first, "mediated assistance" (MA), involves interaction between an assistor and a learner to reveal problems in…

  20. Dynamical supersymmetry breaking

    International Nuclear Information System (INIS)

    Affleck, I.

    1985-03-01

    Supersymmetry, and in particular, dynamical supersymmetry breaking, offers the hope of a natural solution of the gauge hierarchy problem in grand unification. I briefly review recent work on dynamical supersymmetry breaking in four-dimensional Higgs theories and its application to grand unified model building

  1. Dynamic Latent Classification Model

    DEFF Research Database (Denmark)

    Zhong, Shengtong; Martínez, Ana M.; Nielsen, Thomas Dyhre

    as possible. Motivated by this problem setting, we propose a generative model for dynamic classification in continuous domains. At each time point the model can be seen as combining a naive Bayes model with a mixture of factor analyzers (FA). The latent variables of the FA are used to capture the dynamics...

  2. Dynamic combinatorial chemistry

    NARCIS (Netherlands)

    Otto, Sijbren; Furlan, Ricardo L.E.; Sanders, Jeremy K.M.

    2002-01-01

    A combinatorial library that responds to its target by increasing the concentration of strong binders at the expense of weak binders sounds ideal. Dynamic combinatorial chemistry has the potential to achieve exactly this. In this review, we will highlight the unique features that distinguish dynamic

  3. Bursty human dynamics

    CERN Document Server

    Karsai, Márton; Kaski, Kimmo

    2018-01-01

    This book provides a comprehensive overview on emergent bursty patterns in the dynamics of human behaviour. It presents common and alternative understanding of the investigated phenomena, and points out open questions worthy of further investigations. The book is structured as follows. In the introduction the authors discuss the motivation of the field, describe bursty phenomena in case of human behaviour, and relate it to other disciplines. The second chapter addresses the measures commonly used to characterise heterogeneous signals, bursty human dynamics, temporal paths, and correlated behaviour. These definitions are first introduced to set the basis for the discussion of the third chapter about the observations of bursty human patterns in the dynamics of individuals, dyadic interactions, and collective behaviour. The subsequent fourth chapter discusses the models of bursty human dynamics. Various mechanisms have been proposed about the source of the heterogeneities in human dynamics, which leads to the in...

  4. Nonlinear dynamics of structures

    CERN Document Server

    Oller, Sergio

    2014-01-01

    This book lays the foundation of knowledge that will allow a better understanding of nonlinear phenomena that occur in structural dynamics.   This work is intended for graduate engineering students who want to expand their knowledge on the dynamic behavior of structures, specifically in the nonlinear field, by presenting the basis of dynamic balance in non‐linear behavior structures due to the material and kinematics mechanical effects.   Particularly, this publication shows the solution of the equation of dynamic equilibrium for structure with nonlinear time‐independent materials (plasticity, damage and frequencies evolution), as well as those time dependent non‐linear behavior materials (viscoelasticity and viscoplasticity). The convergence conditions for the non‐linear dynamic structure solution  are studied, and the theoretical concepts and its programming algorithms are presented.  

  5. Vehicle Dynamics and Control

    CERN Document Server

    Rajamani, Rajesh

    2012-01-01

    Vehicle Dynamics and Control provides a comprehensive coverage of vehicle control systems and the dynamic models used in the development of these control systems. The control system applications covered in the book include cruise control, adaptive cruise control, ABS, automated lane keeping, automated highway systems, yaw stability control, engine control, passive, active and semi-active suspensions, tire-road friction coefficient estimation, rollover prevention, and hybrid electric vehicle. In developing the dynamic model for each application, an effort is made to both keep the model simple enough for control system design but at the same time rich enough to capture the essential features of the dynamics. A special effort has been made to explain the several different tire models commonly used in literature and to interpret them physically. In the second edition of the book, chapters on roll dynamics, rollover prevention and hybrid electric vehicles have been added, and the chapter on electronic stability co...

  6. Bayesian dynamic mediation analysis.

    Science.gov (United States)

    Huang, Jing; Yuan, Ying

    2017-12-01

    Most existing methods for mediation analysis assume that mediation is a stationary, time-invariant process, which overlooks the inherently dynamic nature of many human psychological processes and behavioral activities. In this article, we consider mediation as a dynamic process that continuously changes over time. We propose Bayesian multilevel time-varying coefficient models to describe and estimate such dynamic mediation effects. By taking the nonparametric penalized spline approach, the proposed method is flexible and able to accommodate any shape of the relationship between time and mediation effects. Simulation studies show that the proposed method works well and faithfully reflects the true nature of the mediation process. By modeling mediation effect nonparametrically as a continuous function of time, our method provides a valuable tool to help researchers obtain a more complete understanding of the dynamic nature of the mediation process underlying psychological and behavioral phenomena. We also briefly discuss an alternative approach of using dynamic autoregressive mediation model to estimate the dynamic mediation effect. The computer code is provided to implement the proposed Bayesian dynamic mediation analysis. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  7. Dynamics of aesthetic appreciation

    Science.gov (United States)

    Carbon, Claus-Christian

    2012-03-01

    Aesthetic appreciation is a complex cognitive processing with inherent aspects of cold as well as hot cognition. Research from the last decades of empirical has shown that evaluations of aesthetic appreciation are highly reliable. Most frequently, facial attractiveness was used as the corner case for investigating aesthetic appreciation. Evaluating facial attractiveness shows indeed high internal consistencies and impressively high inter-rater reliabilities, even across cultures. Although this indicates general and stable mechanisms underlying aesthetic appreciation, it is also obvious that our taste for specific objects changes dynamically. Aesthetic appreciation on artificial object categories, such as fashion, design or art is inherently very dynamic. Gaining insights into the cognitive mechanisms that trigger and enable corresponding changes of aesthetic appreciation is of particular interest for research as this will provide possibilities to modeling aesthetic appreciation for longer durations and from a dynamic perspective. The present paper refers to a recent two-step model ("the dynamical two-step-model of aesthetic appreciation"), dynamically adapting itself, which accounts for typical dynamics of aesthetic appreciation found in different research areas such as art history, philosophy and psychology. The first step assumes singular creative sources creating and establishing innovative material towards which, in a second step, people adapt by integrating it into their visual habits. This inherently leads to dynamic changes of the beholders' aesthetic appreciation.

  8. Perspectives of nonlinear dynamics

    International Nuclear Information System (INIS)

    Jackson, E.A.

    1985-03-01

    Four lectures were given weekly in October and November, 1984, and some of the ideas presented here will be of use in the future. First, a brief survey of the historical development of nonlinear dynamics since about 1890 was given, and then, a few topics were discussed in detail. The objective was to introduce some of many concepts and methods which are presently used for describing nonlinear dynamics. The symbiotic relationship between sciences of all types and mathematics, two main categories of the models describing nature, the method for describing the dynamics of a system, the idea of control parameters and topological dimension, the asymptotic properties of dynamics, abstract dynamics, the concept of embedding, singular perturbation theory, strange attractor, Fermi-Pasta-Ulam phenomena, an example of computer heuristics, the idea of elementary catastrophe theory and so on were explained. The logistic map is the simplest introduction to complex dynamics. The complicated dynamics is referred to as strange attractors. Two-dimensional maps are the highest dimensional maps commonly studied. These were discussed in detail. (Kako, I.)

  9. Dynamic translocation of ligand-complexed DNA through solid-state nanopores with optical tweezers

    International Nuclear Information System (INIS)

    Sischka, Andy; Spiering, Andre; Anselmetti, Dario; Khaksar, Maryam; Laxa, Miriam; Koenig, Janine; Dietz, Karl-Josef

    2010-01-01

    We investigated the threading and controlled translocation of individual lambda-DNA (λ-DNA) molecules through solid-state nanopores with piconewton force sensitivity, millisecond time resolution and picoampere ionic current sensitivity with a set-up combining quantitative 3D optical tweezers (OT) with electrophysiology. With our virtually interference-free OT set-up the binding of RecA and single peroxiredoxin protein molecules to λ-DNA was quantitatively investigated during dynamic translocation experiments where effective forces and respective ionic currents of the threaded DNA molecule through the nanopore were measured during inward and outward sliding. Membrane voltage-dependent experiments of reversible single protein/DNA translocation scans yield hysteresis-free, asymmetric single-molecule fingerprints in the measured force and conductance signals that can be attributed to the interplay of optical trap and electrostatic nanopore potentials. These experiments allow an exact localization of the bound protein along the DNA strand and open fascinating applications for label-free detection of DNA-binding ligands, where structural and positional binding phenomena can be investigated at a single-molecule level.

  10. Emergent structures and dynamics in suspensions of self-phoretic colloids

    Science.gov (United States)

    Scagliarini, Andrea; Pagonabarraga, Ignacio

    2013-11-01

    Active fluids, such as suspensions of self-propelled particles , are a fascinating example of Soft Matter displaying complex collective behaviours which provide challenges in non-equilibrium Statistical Physics. The recent development of techniques to assemble miniaturized devices has led to a growing interest for micro and nanoscale engines that can perform autonomous motion (``microrobots''), as, for instance, self-phoretic colloids, for which the propulsion is induced by the generation of a chemical species in a reaction catalyzed at the particle surface. We perform a mesoscopic numerical study of suspensions of self-phoretic colloids. We show that, at changing the sign of the phoretic mobility (which accounts for the colloid-solute interactions), the system switches from a cluster phase to a state with slowed dynamics. We find that the cluster size distribution follows an exponential behaviour, with a characteristic size growing linearly with the colloid activity, while the density fluctuations grow as a power-law with an exponent depending on the cluster fractal dimension.We single out hydrodynamic interactions, showing that their effect is to work against cluster formation. For positive μ, we observe that colloids tend to reach an ordered state on a triangular lattice.

  11. Physics of the Kitaev Model: Fractionalization, Dynamic Correlations, and Material Connections

    Science.gov (United States)

    Hermanns, M.; Kimchi, I.; Knolle, J.

    2018-03-01

    Quantum spin liquids have fascinated condensed matter physicists for decades because of their unusual properties such as spin fractionalization and long-range entanglement. Unlike conventional symmetry breaking, the topological order underlying quantum spin liquids is hard to detect experimentally. Even theoretical models are scarce for which the ground state is established to be a quantum spin liquid. The Kitaev honeycomb model and its generalizations to other tricoordinated lattices are chief counterexamples - they are exactly solvable, harbor a variety of quantum spin liquid phases, and are also relevant for certain transition metal compounds including the polymorphs of (Na,Li)2IrO3 iridates and RuCl3. In this review, we give an overview of the rich physics of the Kitaev model, including two-dimensional and three-dimensional fractionalization as well as dynamic correlations and behavior at finite temperatures. We discuss the different materials and argue how the Kitaev model physics can be relevant even though most materials show magnetic ordering at low temperatures.

  12. Operational Dynamic Configuration Analysis

    Science.gov (United States)

    Lai, Chok Fung; Zelinski, Shannon

    2010-01-01

    Sectors may combine or split within areas of specialization in response to changing traffic patterns. This method of managing capacity and controller workload could be made more flexible by dynamically modifying sector boundaries. Much work has been done on methods for dynamically creating new sector boundaries [1-5]. Many assessments of dynamic configuration methods assume the current day baseline configuration remains fixed [6-7]. A challenging question is how to select a dynamic configuration baseline to assess potential benefits of proposed dynamic configuration concepts. Bloem used operational sector reconfigurations as a baseline [8]. The main difficulty is that operational reconfiguration data is noisy. Reconfigurations often occur frequently to accommodate staff training or breaks, or to complete a more complicated reconfiguration through a rapid sequence of simpler reconfigurations. Gupta quantified a few aspects of airspace boundary changes from this data [9]. Most of these metrics are unique to sector combining operations and not applicable to more flexible dynamic configuration concepts. To better understand what sort of reconfigurations are acceptable or beneficial, more configuration change metrics should be developed and their distribution in current practice should be computed. This paper proposes a method to select a simple sequence of configurations among operational configurations to serve as a dynamic configuration baseline for future dynamic configuration concept assessments. New configuration change metrics are applied to the operational data to establish current day thresholds for these metrics. These thresholds are then corroborated, refined, or dismissed based on airspace practitioner feedback. The dynamic configuration baseline selection method uses a k-means clustering algorithm to select the sequence of configurations and trigger times from a given day of operational sector combination data. The clustering algorithm selects a simplified

  13. Dynamic training algorithm for dynamic neural networks

    International Nuclear Information System (INIS)

    Tan, Y.; Van Cauwenberghe, A.; Liu, Z.

    1996-01-01

    The widely used backpropagation algorithm for training neural networks based on the gradient descent has a significant drawback of slow convergence. A Gauss-Newton method based recursive least squares (RLS) type algorithm with dynamic error backpropagation is presented to speed-up the learning procedure of neural networks with local recurrent terms. Finally, simulation examples concerning the applications of the RLS type algorithm to identification of nonlinear processes using a local recurrent neural network are also included in this paper

  14. Living with Dynamic Concepts in Dynamic Environments

    DEFF Research Database (Denmark)

    Rehm, Matthias

    2003-01-01

    a dynamic perspective, concepts depend on different factors like the learning process, the environment, i.e. the situational setting. It is indispensable for an agent to create individual concepts that adhere to restrictions imposed by the environment and the society it is living in. It is shown...... that changes in the environment lead to changes in existing concepts and to establishing new ones with only a small irritation in the use of the old ones....

  15. Fluid dynamics transactions

    CERN Document Server

    Fiszdon, W

    1965-01-01

    Fluid Dynamics Transactions, Volume 2 compiles 46 papers on fluid dynamics, a subdiscipline of fluid mechanics that deals with fluid flow. The topics discussed in this book include developments in interference theory for aeronautical applications; diffusion from sources in a turbulent boundary layer; unsteady motion of a finite wing span in a compressible medium; and wall pressure covariance and comparison with experiment. The certain classes of non-stationary axially symmetric flows in magneto-gas-dynamics; description of the phenomenon of secondary flows in curved channels by means of co

  16. Advances in Dynamic Games

    CERN Document Server

    Breton, Michele

    2011-01-01

    This book focuses on various aspects of dynamic game theory, presenting state-of-the-art research and serving as a testament to the vitality and growth of the field of dynamic games and their applications. The selected contributions, written by experts in their respective disciplines, are outgrowths of presentations originally given at the 13th International Symposium of Dynamic Games and Applications held in WrocACaw. The book covers a variety of topics, ranging from theoretical developments in game theory and algorithmic methods to applications, examples, and analysis in fields as varied as

  17. Basic structural dynamics

    CERN Document Server

    Anderson, James C

    2012-01-01

    A concise introduction to structural dynamics and earthquake engineering Basic Structural Dynamics serves as a fundamental introduction to the topic of structural dynamics. Covering single and multiple-degree-of-freedom systems while providing an introduction to earthquake engineering, the book keeps the coverage succinct and on topic at a level that is appropriate for undergraduate and graduate students. Through dozens of worked examples based on actual structures, it also introduces readers to MATLAB, a powerful software for solving both simple and complex structural d

  18. High enthalpy gas dynamics

    CERN Document Server

    Rathakrishnan, Ethirajan

    2014-01-01

    This is an introductory level textbook which explains the elements of high temperature and high-speed gas dynamics. written in a clear and easy to follow style, the author covers all the latest developments in the field including basic thermodynamic principles, compressible flow regimes and waves propagation in one volume covers theoretical modeling of High Enthalpy Flows, with particular focus on problems in internal and external gas-dynamic flows, of interest in the fields of rockets propulsion and hypersonic aerodynamics High enthalpy gas dynamics is a compulsory course for aerospace engine

  19. Shadowing in dynamical systems

    CERN Document Server

    Pilyugin, Sergei Yu

    1999-01-01

    This book is an introduction to the theory of shadowing of approximate trajectories in dynamical systems by exact ones. This is the first book completely devoted to the theory of shadowing. It shows the importance of shadowing theory for both the qualitative theory of dynamical systems and the theory of numerical methods. Shadowing Methods allow us to estimate differences between exact and approximate solutions on infinite time intervals and to understand the influence of error terms. The book is intended for specialists in dynamical systems, for researchers and graduate students in the theory of numerical methods.

  20. Dynamics from diffraction

    International Nuclear Information System (INIS)

    Goodwin, Andrew L.; Tucker, Matthew G.; Cope, Elizabeth R.; Dove, Martin T.; Keen, David A.

    2006-01-01

    We explore the possibility that detailed dynamical information might be extracted from powder diffraction data. Our focus is a recently reported technique that employs statistical analysis of atomistic configurations to calculate dynamical properties from neutron total scattering data. We show that it is possible to access the phonon dispersion of low-frequency modes using such an approach, without constraining the results in terms of some pre-defined dynamical model. The high-frequency regions of the phonon spectrum are found to be less well preserved in the diffraction data

  1. Fundamentals of gas dynamics

    CERN Document Server

    Babu, V

    2014-01-01

    Fundamentals of Gas Dynamics, Second Edition isa comprehensively updated new edition and now includes a chapter on the gas dynamics of steam. It covers the fundamental concepts and governing equations of different flows, and includes end of chapter exercises based on the practical applications. A number of useful tables on the thermodynamic properties of steam are also included.Fundamentals of Gas Dynamics, Second Edition begins with an introduction to compressible and incompressible flows before covering the fundamentals of one dimensional flows and normal shock wav

  2. Stability of dynamical systems

    CERN Document Server

    Liao, Xiaoxin; Yu, P 0

    2007-01-01

    The main purpose of developing stability theory is to examine dynamic responses of a system to disturbances as the time approaches infinity. It has been and still is the object of intense investigations due to its intrinsic interest and its relevance to all practical systems in engineering, finance, natural science and social science. This monograph provides some state-of-the-art expositions of major advances in fundamental stability theories and methods for dynamic systems of ODE and DDE types and in limit cycle, normal form and Hopf bifurcation control of nonlinear dynamic systems.ʺ Presents

  3. Theoretical Fluid Dynamics

    CERN Document Server

    Shivamoggi, Bhimsen K

    1998-01-01

    "Although there are many texts and monographs on fluid dynamics, I do not know of any which is as comprehensive as the present book. It surveys nearly the entire field of classical fluid dynamics in an advanced, compact, and clear manner, and discusses the various conceptual and analytical models of fluid flow." - Foundations of Physics on the first edition. Theoretical Fluid Dynamics functions equally well as a graduate-level text and a professional reference. Steering a middle course between the empiricism of engineering and the abstractions of pure mathematics, the author focuses

  4. Discrete Dynamics Lab

    Science.gov (United States)

    Wuensche, Andrew

    DDLab is interactive graphics software for creating, visualizing, and analyzing many aspects of Cellular Automata, Random Boolean Networks, and Discrete Dynamical Networks in general and studying their behavior, both from the time-series perspective — space-time patterns, and from the state-space perspective — attractor basins. DDLab is relevant to research, applications, and education in the fields of complexity, self-organization, emergent phenomena, chaos, collision-based computing, neural networks, content addressable memory, genetic regulatory networks, dynamical encryption, generative art and music, and the study of the abstract mathematical/physical/dynamical phenomena in their own right.

  5. Dynamic Systems and Control Engineering

    International Nuclear Information System (INIS)

    Kim, Jong Seok

    1994-02-01

    This book deals with introduction of dynamic system and control engineering, frequency domain modeling of dynamic system, temporal modeling of dynamic system, typical dynamic system and automatic control device, performance and stability of control system, root locus analysis, analysis of frequency domain dynamic system, design of frequency domain dynamic system, design and analysis of space, space of control system and digital control system such as control system design of direct digital and digitalization of consecutive control system.

  6. Dynamic Systems and Control Engineering

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jong Seok

    1994-02-15

    This book deals with introduction of dynamic system and control engineering, frequency domain modeling of dynamic system, temporal modeling of dynamic system, typical dynamic system and automatic control device, performance and stability of control system, root locus analysis, analysis of frequency domain dynamic system, design of frequency domain dynamic system, design and analysis of space, space of control system and digital control system such as control system design of direct digital and digitalization of consecutive control system.

  7. Liquid Sloshing Dynamics

    Science.gov (United States)

    Ibrahim, Raouf A.

    2005-06-01

    The problem of liquid sloshing in moving or stationary containers remains of great concern to aerospace, civil, and nuclear engineers; physicists; designers of road tankers and ship tankers; and mathematicians. Beginning with the fundamentals of liquid sloshing theory, this book takes the reader systematically from basic theory to advanced analytical and experimental results in a self-contained and coherent format. The book is divided into four sections. Part I deals with the theory of linear liquid sloshing dynamics; Part II addresses the nonlinear theory of liquid sloshing dynamics, Faraday waves, and sloshing impacts; Part III presents the problem of linear and nonlinear interaction of liquid sloshing dynamics with elastic containers and supported structures; and Part IV considers the fluid dynamics in spinning containers and microgravity sloshing. This book will be invaluable to researchers and graduate students in mechanical and aeronautical engineering, designers of liquid containers, and applied mathematicians.

  8. Ansatz for dynamical hierarchies

    DEFF Research Database (Denmark)

    Rasmussen, S.; Baas, N.A.; Mayer, B.

    2001-01-01

    Complex, robust functionalities can be generated naturally in at least two ways: by the assembly of structures and by the evolution of structures. This work is concerned with spontaneous formation of structures. We define the notion of dynamical hierarchies in natural systems and show...... the importance of this particular kind of organization for living systems. We then define a framework that enables us to formulate, investigate, and manipulate such dynamical hierarchies. This framework allows us to simultaneously investigate different levels of description together with them interrelationship...... three. Formulating this system as a simple two-dimensional molecular dynamics (MD) lattice gas allows us within one dynamical system to demonstrate the successive emergence of two higher levels (three levels all together) of robust structures with associated properties. Second, we demonstrate how...

  9. Longitudinal beam dynamics

    International Nuclear Information System (INIS)

    Tecker, F

    2014-01-01

    The course gives a summary of longitudinal beam dynamics for both linear and circular accelerators. After discussing different types of acceleration methods and synchronism conditions, it focuses on the particle motion in synchrotrons

  10. Stochastic dynamics and irreversibility

    CERN Document Server

    Tomé, Tânia

    2015-01-01

    This textbook presents an exposition of stochastic dynamics and irreversibility. It comprises the principles of probability theory and the stochastic dynamics in continuous spaces, described by Langevin and Fokker-Planck equations, and in discrete spaces, described by Markov chains and master equations. Special concern is given to the study of irreversibility, both in systems that evolve to equilibrium and in nonequilibrium stationary states. Attention is also given to the study of models displaying phase transitions and critical phenomema both in thermodynamic equilibrium and out of equilibrium. These models include the linear Glauber model, the Glauber-Ising model, lattice models with absorbing states such as the contact process and those used in population dynamic and spreading of epidemic, probabilistic cellular automata, reaction-diffusion processes, random sequential adsorption and dynamic percolation. A stochastic approach to chemical reaction is also presented.The textbook is intended for students of ...

  11. Supervision and group dynamics

    DEFF Research Database (Denmark)

    Hansen, Søren; Jensen, Lars Peter

    2004-01-01

     An important aspect of the problem based and project organized study at Aalborg University is the supervision of the project groups. At the basic education (first year) it is stated in the curriculum that part of the supervisors' job is to deal with group dynamics. This is due to the experience...... that many students are having difficulties with practical issues such as collaboration, communication, and project management. Most supervisors either ignore this demand, because they do not find it important or they find it frustrating, because they do not know, how to supervise group dynamics...... as well as at Aalborg University. The first visible result has been participating supervisors telling us that the course has inspired them to try supervising group dynamics in the future. This paper will explore some aspects of supervising group dynamics as well as, how to develop the Aalborg model...

  12. Equivalent Dynamic Models.

    Science.gov (United States)

    Molenaar, Peter C M

    2017-01-01

    Equivalences of two classes of dynamic models for weakly stationary multivariate time series are discussed: dynamic factor models and autoregressive models. It is shown that exploratory dynamic factor models can be rotated, yielding an infinite set of equivalent solutions for any observed series. It also is shown that dynamic factor models with lagged factor loadings are not equivalent to the currently popular state-space models, and that restriction of attention to the latter type of models may yield invalid results. The known equivalent vector autoregressive model types, standard and structural, are given a new interpretation in which they are conceived of as the extremes of an innovating type of hybrid vector autoregressive models. It is shown that consideration of hybrid models solves many problems, in particular with Granger causality testing.

  13. Invitation to dynamical systems

    CERN Document Server

    Scheinerman, Edward R

    2012-01-01

    This text is designed for those who wish to study mathematics beyond linear algebra but are unready for abstract material. Rather than a theorem-proof-corollary exposition, it stresses geometry, intuition, and dynamical systems. 1996 edition.

  14. Transonic Dynamics Tunnel (TDT)

    Data.gov (United States)

    Federal Laboratory Consortium — The Transonic Dynamics Tunnel (TDT) is a continuous flow wind-tunnel facility capable of speeds up to Mach 1.2 at stagnation pressures up to one atmosphere. The TDT...

  15. Advances in soil dynamics

    DEFF Research Database (Denmark)

    Advances in Soil Dynamics, Volume 3, represents the culmination of the work undertaken by the Advances in Soil Dynamics Monograph Committee, PM-45-01, about 15 years ago to summarize important developments in this field over the last 35 years. When this project was initiated, the main goal...... was to abridge major strides made in the general area of soil dynamics during the sixties, seventies, and eighties. However, by about the mid-nineties soil dynamics research in the US and much of the developed world had come to a virtual standstill. Although significant progress was made prior to the mid......-nineties, we still do not have a sound fundamental knowledge of soil-machine and soil-plant interactions. It is the hope of the editors that these three volumes will provide a ready reference for much needed future research in this area....

  16. based dynamic voltage restorer

    African Journals Online (AJOL)

    HOD

    operation due to presence of increased use of nonlinear loads (computers, microcontrollers ... simulations of a dynamic voltage restorer (DVR) was achieved using MATLAB/Simulink. ..... using Discrete PWM generator, then the IGBT inverter.

  17. Peri-dynamics

    International Nuclear Information System (INIS)

    Littlewood, D.

    2015-01-01

    Peri-dynamics, a nonlocal extension of continuum mechanics, is a natural framework for capturing constitutive response and modelling pervasive material failure and fracture. Unlike classical approaches incorporating partial derivatives, the peri-dynamic governing equations utilise integral expressions that remain valid in the presence of discontinuities such as cracks. The mathematical theory of peri-dynamics unifies the mechanics of continuous media, cracks, and discrete particles. The result is a consistent framework for capturing a wide range of constitutive responses, including inelasticity, in combination with robust material failure laws. Peri-dynamics has been implemented in a number of computational simulation codes, including the open source code Peridigm and the Sierra/SolidMechanics analysis code at Sandia National Laboratories. (author)

  18. Mercury's Dynamic Magnetosphere

    Science.gov (United States)

    Imber, S. M.

    2018-05-01

    The global dynamics of Mercury's magnetosphere will be discussed, focussing on observed asymmetries in the magnetotail and on the precipitation of particles of magnetospheric origin onto the nightside planetary surface.

  19. Market Squid Population Dynamics

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains population dynamics data on paralarvae, juvenile and adult market squid collected off California and the US Pacific Northwest. These data were...

  20. Gun Dynamics Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — The Gun Dynamics Laboratory is a research multi-task facility, which includes two firing bays, a high bay area and a second floor laboratory space. The high bay area...

  1. Dual Dynamic Programming - DDP

    International Nuclear Information System (INIS)

    Velasquez Bermudez, Jesus M

    1998-01-01

    Objections are presented to the mathematical formulation of the denominated Dual Dynamic programming-PDD that is the theoretical base of several computational model available for the optimal formulation of interconnected hydrothermal systems

  2. Controlling Uncertain Dynamical Systems

    Indian Academy of Sciences (India)

    Author Affiliations. N Ananthkrishnan1 Rashi Bansal2. Head, CAE Analysis & Design Zeus Numerix Pvt Ltd. M-03, SINE, IIT Bombay Powai Mumbai 400076, India. MTech (Aerospace Engineering) with specialization in Dynamics & Control from IIT Bombay.

  3. Instantaneous and dynamical decoherence

    Science.gov (United States)

    Polonyi, Janos

    2018-04-01

    Two manifestations of decoherence, called instantaneous and dynamical, are investigated. The former reflects the suppression of the interference between the components of the current state while the latter reflects that within the initial state. These types of decoherence are computed in the case of the Brownian motion and the harmonic and anharmonic oscillators within the semiclassical approximation. A remarkable phenomenon, namely the opposite orientation of the time arrow of the dynamical variables compared to that of the quantum fluctuations generates a double exponential time dependence of the dynamical decoherence in the presence of a harmonic force. For the weakly anharmonic oscillator the dynamical decoherence is found to depend in a singular way on the amount of the anharmonicity.

  4. Structural dynamic modification

    Indian Academy of Sciences (India)

    and stiffness matrices) andaor modal parameters, in order to acquire some ... For the above reasons, another modification approach is presented here ... The data necessary to solve the direct problem are dynamic behaviour of the original.

  5. Dynamics of interstellar matter

    International Nuclear Information System (INIS)

    Kahn, F.D.

    1975-01-01

    A review of the dynamics of interstellar matter is presented, considering the basic equations of fluid flow, plane waves, shock waves, spiral structure, thermal instabilities and early star cocoons. (B.R.H.)

  6. Fish population dynamics

    National Research Council Canada - National Science Library

    Gulland, J. A

    1977-01-01

    This book describes how the dynamics of fish populations can be analysed in terms of the factors affecting their rates of growth, mortality and reproduction, with particular emphasis on the effects of fishing...

  7. Dynamics of glassy systems

    International Nuclear Information System (INIS)

    Cugliandolo, Leticia F.

    2003-09-01

    These lecture notes can be read in two ways. The first two Sections contain a review of the phenomenology of several physical systems with slow nonequilibrium dynamics. In the Conclusions we summarize the scenario for this temporal evolution derived from the solution to some solvable models (p spin and the like) that are intimately connected to the mode coupling approach (and similar ones) to super-cooled liquids. At the end we list a number of open problems of great relevance in this context. These Sections can be read independently of the body of the paper where we present some of the basic analytic techniques used to study the out of equilibrium dynamics of classical and quantum models with and without disorder. We start the technical part by briefly discussing the role played by the environment and by introducing and comparing its representation in the equilibrium and dynamic treatment of classical and quantum systems. We next explain the role played by explicit quenched disorder in both approaches. Later on we focus on analytical techniques; we expand on the dynamic functional methods, and the diagrammatic expansions and resummations used to derive macroscopic equations from the microscopic dynamics. We show why the macroscopic dynamic equations for disordered models and those resulting from self-consistent approximations to non-disordered ones coincide. We review some generic properties of dynamic systems evolving out of equilibrium like the modifications of the fluctuation-dissipation theorem, generic scaling forms of the correlation functions, etc. Finally we solve a family of mean-field models. The connection between the dynamic treatment and the analysis of the free-energy landscape of these models is also presented. We use pedagogical examples all along these lectures to illustrate the properties and results. (author)

  8. Quantum net dynamics

    International Nuclear Information System (INIS)

    Finkelstein, D.

    1989-01-01

    The quantum net unifies the basic principles of quantum theory and relativity in a quantum spacetime having no ultraviolet infinities, supporting the Dirac equation, and having the usual vacuum as a quantum condensation. A correspondence principle connects nets to Schwinger sources and further unifies the vertical structure of the theory, so that the functions of the many hierarchic levels of quantum field theory (predicate algebra, set theory, topology,hor-ellipsis, quantum dynamics) are served by one in quantum net dynamics

  9. Dynamics of curved fronts

    CERN Document Server

    Pelce, Pierre

    1989-01-01

    In recent years, much progress has been made in the understanding of interface dynamics of various systems: hydrodynamics, crystal growth, chemical reactions, and combustion. Dynamics of Curved Fronts is an important contribution to this field and will be an indispensable reference work for researchers and graduate students in physics, applied mathematics, and chemical engineering. The book consist of a 100 page introduction by the editor and 33 seminal articles from various disciplines.

  10. Dynamic map labeling.

    Science.gov (United States)

    Been, Ken; Daiches, Eli; Yap, Chee

    2006-01-01

    We address the problem of filtering, selecting and placing labels on a dynamic map, which is characterized by continuous zooming and panning capabilities. This consists of two interrelated issues. The first is to avoid label popping and other artifacts that cause confusion and interrupt navigation, and the second is to label at interactive speed. In most formulations the static map labeling problem is NP-hard, and a fast approximation might have O(nlogn) complexity. Even this is too slow during interaction, when the number of labels shown can be several orders of magnitude less than the number in the map. In this paper we introduce a set of desiderata for "consistent" dynamic map labeling, which has qualities desirable for navigation. We develop a new framework for dynamic labeling that achieves the desiderata and allows for fast interactive display by moving all of the selection and placement decisions into the preprocessing phase. This framework is general enough to accommodate a variety of selection and placement algorithms. It does not appear possible to achieve our desiderata using previous frameworks. Prior to this paper, there were no formal models of dynamic maps or of dynamic labels; our paper introduces both. We formulate a general optimization problem for dynamic map labeling and give a solution to a simple version of the problem. The simple version is based on label priorities and a versatile and intuitive class of dynamic label placements we call "invariant point placements". Despite these restrictions, our approach gives a useful and practical solution. Our implementation is incorporated into the G-Vis system which is a full-detail dynamic map of the continental USA. This demo is available through any browser.

  11. Dynamical quantum teleportation

    Energy Technology Data Exchange (ETDEWEB)

    Muschik, Christine [ICFO-Institut de Ciencies Fotoniques (Spain); Polzik, Eugene [Niels Bohr Institute (Denmark); Cirac, Ignacio [Max-Planck-Institute (Germany)

    2013-07-01

    We introduce two protocols for inducing non-local dynamics between two separate parties. The first scheme allows for the engineering of an interaction between the two remote systems, while the second protocol induces a dynamics in one of the parties, which is controlled by the other one. Both schemes apply to continuous variable systems, run continuously in time and are based on instantaneous feedback.

  12. Dynamic Strategic Information Transmission

    OpenAIRE

    Mikhail Golosov; Vasiliki Skreta; Aleh Tsyvinski; Andrea Wilson

    2011-01-01

    This paper studies strategic information transmission in a dynamic environment where, each period, a privately informed expert sends a message and a decision maker takes an action. Our main result is that, in contrast to a static environment, full information revelation is possible. The gradual revelation of information and the eventual full revelation is supported by the dynamic rewards and punishments. The construction of a fully revealing equilibrium relies on two key features. The first f...

  13. Dynamics and causality constraints

    International Nuclear Information System (INIS)

    Sousa, Manoelito M. de

    2001-04-01

    The physical meaning and the geometrical interpretation of causality implementation in classical field theories are discussed. Causality in field theory are kinematical constraints dynamically implemented via solutions of the field equation, but in a limit of zero-distance from the field sources part of these constraints carries a dynamical content that explains old problems of classical electrodynamics away with deep implications to the nature of physicals interactions. (author)

  14. Dynamics of magnetospheric plasmas

    International Nuclear Information System (INIS)

    Horwitz, J.L.

    1985-01-01

    The dynamical behavior of the magnetospheric plasmas which control the electrostatic charging of spacecraft is the result of the complex interaction of a variety of production, loss, transport, and energization mechanisms in the magnetosphere. This paper is intended to provide the spacecraft engineer with a foundation in the basic morphology and controlling processes pertaining to magnetospheric plasma dynamics in the inner magnetosphere, including the synchronous orbit region. 32 references

  15. Channeling and dynamic chaos

    Energy Technology Data Exchange (ETDEWEB)

    Bolotin, IU L; Gonchar, V IU; Truten, V I; Shulga, N F

    1986-01-01

    It is shown that axial channeling of relativistic electrons can give rise to the effect of dynamic chaos which involves essentially chaotic motion of a particle in the channel. The conditions leading to the effect of dynamic chaos and the manifestations of this effect in physical processes associated with the passage of particles through a crystal are examined using a silicon crystal as an example. 7 references.

  16. Fusion-fission dynamics

    International Nuclear Information System (INIS)

    Blocki, J.; Planeta, R.; Brzychczyk, J.; Grotowski, K.

    1992-01-01

    Classical dynamical calculations of the heavy ion induced fission processes have been performed for the reactions 40 Ar+ 141 Pr, 20 Ne+ 165 Ho and 12 C+ 175 Lu leading to the iridium like nucleus. As a result prescission lifetimes were obtained and compared with the experimental values. The comparison between the calculated and experimental lifetimes indicates that the one-body dissipation picture is much more relevant in describing the fusion-fission dynamics than the two-body one. (orig.)

  17. Photochemical reaction dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Moore, B.C. [Lawrence Berkeley Laboratory, Livermore, CA (United States)

    1993-12-01

    The purpose of the program is to develop a fundamental understanding of unimolecular and bimolecular reaction dynamics with application in combustion and energy systems. The energy dependence in ketene isomerization, ketene dissociation dynamics, and carbonyl substitution on organometallic rhodium complexes in liquid xenon have been studied. Future studies concerning unimolecular processes in ketene as well as energy transfer and kinetic studies of methylene radicals are discussed.

  18. Dynamics of Soft Matter

    CERN Document Server

    García Sakai, Victoria; Chen, Sow-Hsin

    2012-01-01

    Dynamics of Soft Matter: Neutron Applications provides an overview of neutron scattering techniques that measure temporal and spatial correlations simultaneously, at the microscopic and/or mesoscopic scale. These techniques offer answers to new questions arising at the interface of physics, chemistry, and biology. Knowledge of the dynamics at these levels is crucial to understanding the soft matter field, which includes colloids, polymers, membranes, biological macromolecules, foams, emulsions towards biological & biomimetic systems, and phenomena involving wetting, friction, adhesion, or micr

  19. The LHC dynamic aperture

    CERN Document Server

    Koutchouk, Jean-Pierre

    1999-01-01

    In 1996, the expected field errors in the dipoles and quadrupoles yielded a long-term dynamic aperture of some 8sigma at injection. The target was set to 12sigma to account for the limitations of our model (imperfections and dynamics). From scaling laws and tracking, a specification for the field imperfections yielding the target dynamic aperture was deduced. The gap between specification and expected errors is being bridged by i) an improvement of the dipole field quality, ii) a balance between geometric and persistent current errors, iii) additional correction circuits (a3 ,b4 ). With the goal in view, the emphasis has now turned to the sensitivity of the dynamic aperture to the optical parameters.The distortion of the dynamics at the lower amplitudes effectively reached by the particles is minimized by optimizing the distribution of the betatron phase advance. At collision energy, the dynamic aperture is limited by the field imperfections of the low-beta triplets, enhanced by the crossing angle. With corre...

  20. Dynamics in Complex Coacervates

    Science.gov (United States)

    Perry, Sarah

    Understanding the dynamics of a material provides detailed information about the self-assembly, structure, and intermolecular interactions present in a material. While rheological methods have long been used for the characterization of complex coacervate-based materials, it remains a challenge to predict the dynamics for a new system of materials. Furthermore, most work reports only qualitative trends exist as to how parameters such as charge stoichiometry, ionic strength, and polymer chain length impact self-assembly and material dynamics, and there is little information on the effects of polymer architecture or the organization of charges within a polymer. We seek to link thermodynamic studies of coacervation phase behavior with material dynamics through a carefully-controlled, systematic study of coacervate linear viscoelasticity for different polymer chemistries. We couple various methods of characterizing the dynamics of polymer-based complex coacervates, including the time-salt superposition methods developed first by Spruijt and coworkers to establish a more mechanistic strategy for comparing the material dynamics and linear viscoelasticity of different systems. Acknowledgment is made to the Donors of the American Chemical Society Petroleum Research Fund for support of this research.

  1. Nuclear quantum many-body dynamics: from collective vibrations to heavy-ion collisions

    International Nuclear Information System (INIS)

    Simenel, Cedric

    2012-01-01

    This report gives a summary of my research on nuclear dynamics during the past ten years. The choice of this field has been motivated by the desire to understand the physics of complex systems obeying quantum mechanics. In particular, the interplay between collective motion and single-particle degrees of freedom is a source of complex and fascinating behaviours. For instance, giant resonances are characterised by a collective vibration of many nucleons, but their decay may occur by the emission of a single nucleon. Another example could be taken from the collision of nuclei where the transfer of few nucleons may have a strong impact on the formation of a compound system is non trivial. To describe these complex systems, one needs to solve the quantum many-body problem. The description of the dynamics of composite systems can be very challenging, especially when two such systems interact. An important goal of nuclear physics is to find a unified way to describe the dynamics of nuclear systems. Ultimately, the same theoretical model should be able to describe vibrations, rotations, fission, all the possible outcomes of heavy-ion collisions (elastic and inelastic scattering, particle transfer, fusion, and multifragmentation), and even the dynamics of neutron star crust. This desire for a global approach to nuclear dynamics has strongly influenced my research activities. In particular, all the numerical applications presented in this report have been obtained from few numerical codes solving equations derived from the same variational principle. Beside the quest for a unified model of nuclear dynamics, possible applications of heavy-ion collisions such as the formation of new nuclei is also a strong motivation for the experimental and theoretical studies of reaction mechanisms. This report is not a review article, but should be considered as a reading guide of the main papers my collaborators and myself have published. It also gives the opportunity to detail some

  2. Offshore pipelaying dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Jensen, Gullik Anthon

    2010-02-15

    This thesis considers three issues regarding modeling of of offshore pipe laying dynamics. These are: (i) the formulation of an offshore pipeline installation operation as a control problem, (ii) the development and passivity analysis of a robotic pipe model for a submerged pipe string, suitable for real-time applications in closed- loop control systems, and (iii) the development and validation of a nonlinear FEM model for simulation and control of the elastic pipeline dynamics, including FEM dynamics of a pipeline combined with vessel dynamics, for simulation and control of pipe lay operations under dynamic positioning Pipeline installation is defined as the operation of positioning a pipeline along a reference path on the seabed from a surface vessel. In control terms, this can be stated as a path-following control problem, where the pipe touchdown point tracks the reference path. However, the only controllers for the touchdown point are the pay-out of pipe into the water, and the motion of the surface vessel. Considering that the pipe is an elastic body, and that both the pipe and the vessel are subject to environmental loads, the control problem that must be considered is a dynamic target-tracking problem, where the surface vessel must track a moving target position on the surface in order to control the position of the touchdown point. A target-tracking controller may be implemented as a guidance system, by extending the dynamic positioning system that is common for pipe lay vessels. An important component in the guidance system is the dynamic pipe model mapping touchdown and surface vessel position. Motivated by robotics, a compact system formulation is derived for the suspended pipeline by considering it as a hyper-redundant manipulator with an arbitrary number of links. This model captures the main dynamics of the pipe, including its geometric configuration and top tension. The model is in the state- space, and on a vectorial form using minimal coordinates

  3. Summary: Hadron dynamics sessions

    International Nuclear Information System (INIS)

    Carroll, A.S.; Londergan, J.T.

    1993-01-01

    Four sessions on Hadron Dynamics were organized at this Workshop. The first topic, QCD Exclusive Reactions and Color Transparency, featured talks by Ralston, Heppelman and Strikman; the second, QCD and Inclusive Reactions had talks by Garvey, Speth and Kisslinger. The third dynamics session, Medium Modification of Elementary Interactions had contributions from Kopeliovich, Alves and Gyulassy; the fourth session Pre-QCD Dynamics and Scattering, had talks by Harris, Myhrer and Brown. An additional joint Spectroscopy/Dynamics session featured talks by Zumbro, Johnson and McClelland. These contributions are reviewed briefly in this summary. Two additional joint sessions between Dynamics and η physics are reviewed by the organizers of the Eta sessions. In such a brief review there is no way the authors can adequately summarize the details of the physics presented here. As a result, they concentrate only on brief impressionistic sketches of the physics topics discussed and their interrelations. They include no bibliography in this summary, but simply refer to the talks given in more detail in the Workshop proceedings. They focus on topics which were common to several presentations in these sessions. First, nuclear and particle descriptions of phenomena are now clearly converging, in both a qualitative and quantitative sense; they show several examples of this convergence. Second, an important issue in hadron dynamics is the extent to which elementary interactions are modified in nuclei at high energies and/or densities, and they illustrate some of these medium effects. Finally, they focus on those dynamical issues where hadron facilities can make an important, or even a unique, contribution to the knowledge of particle and nuclear physics

  4. Riverine habitat dynamics

    Science.gov (United States)

    Jacobson, R.B.

    2013-01-01

    The physical habitat template is a fundamental influence on riverine ecosystem structure and function. Habitat dynamics refers to the variation in habitat through space and time as the result of varying discharge and varying geomorphology. Habitat dynamics can be assessed at spatial scales ranging from the grain (the smallest resolution at which an organism relates to its environment) to the extent (the broadest resolution inclusive of all space occupied during its life cycle). In addition to a potentially broad range of spatial scales, assessments of habitat dynamics may include dynamics of both occupied and nonoccupied habitat patches because of process interactions among patches. Temporal aspects of riverine habitat dynamics can be categorized into hydrodynamics and morphodynamics. Hydrodynamics refers to habitat variation that results from changes in discharge in the absence of significant change of channel morphology and at generally low sediment-transport rates. Hydrodynamic assessments are useful in cases of relatively high flow exceedance (percent of time a flow is equaled or exceeded) or high critical shear stress, conditions that are applicable in many studies of instream flows. Morphodynamics refers to habitat variation resulting from changes to substrate conditions or channel/floodplain morphology. Morphodynamic assessments are necessary when channel and floodplain boundary conditions have been significantly changed, generally by relatively rare flood events or in rivers with low critical shear stress. Morphodynamic habitat variation can be particularly important as disturbance mechanisms that mediate population growth or for providing conditions needed for reproduction, such as channel-migration events that erode cutbanks and provide new pointbar surfaces for germination of riparian trees. Understanding of habitat dynamics is increasing in importance as societal goals shift toward restoration of riverine ecosystems. Effective investment in restoration

  5. Dynamic wall demonstration project

    Energy Technology Data Exchange (ETDEWEB)

    Nakatsui, L.; Mayhew, W.

    1990-12-01

    The dynamic wall concept is a ventilation strategy that can be applied to a single family dwelling. With suitable construction, outside air can be admitted through the exterior walls of the house to the interior space to function as ventilation air. The construction and performance monitoring of a demonstration house built to test the dynamic wall concept in Sherwood Park, Alberta, is described. The project had the objectives of demonstrating and assessing the construction methods; determining the cost-effectiveness of the concept in Alberta; analyzing the operation of the dynamic wall system; and determining how other components and systems in the house interact with the dynamic wall. The exterior wall construction consisted of vinyl siding, spun-bonded polyolefin-backed (SBPO) rigid fiberglass sheathing, 38 mm by 89 mm framing, fiberglass batt insulation and 12.7 mm drywall. The mechanical system was designed to operate in the dynamic (negative pressure) mode, however flexibility was provided to allow operation in the static (balanced pressure) mode to permit monitoring of the walls as if they were in a conventional house. The house was monitored by an extensive computerized monitoring system. Dynamic wall operation was dependent on pressure and temperature differentials between indoor and outdoor as well as wind speed and direction. The degree of heat gain was found to be ca 74% of the indoor-outdoor temperature differential. Temperature of incoming dynamic air was significantly affected by solar radiation and measurement of indoor air pollutants found no significant levels. 4 refs., 34 figs., 11 tabs.

  6. Astrophysical fluid dynamics

    Science.gov (United States)

    Ogilvie, Gordon I.

    2016-06-01

    > These lecture notes and example problems are based on a course given at the University of Cambridge in Part III of the Mathematical Tripos. Fluid dynamics is involved in a very wide range of astrophysical phenomena, such as the formation and internal dynamics of stars and giant planets, the workings of jets and accretion discs around stars and black holes and the dynamics of the expanding Universe. Effects that can be important in astrophysical fluids include compressibility, self-gravitation and the dynamical influence of the magnetic field that is `frozen in' to a highly conducting plasma. The basic models introduced and applied in this course are Newtonian gas dynamics and magnetohydrodynamics (MHD) for an ideal compressible fluid. The mathematical structure of the governing equations and the associated conservation laws are explored in some detail because of their importance for both analytical and numerical methods of solution, as well as for physical interpretation. Linear and nonlinear waves, including shocks and other discontinuities, are discussed. The spherical blast wave resulting from a supernova, and involving a strong shock, is a classic problem that can be solved analytically. Steady solutions with spherical or axial symmetry reveal the physics of winds and jets from stars and discs. The linearized equations determine the oscillation modes of astrophysical bodies, as well as their stability and their response to tidal forcing.

  7. Emergence in Dynamical Systems

    Directory of Open Access Journals (Sweden)

    John Collier

    2013-12-01

    Full Text Available Emergence is a term used in many contexts in current science; it has become fashionable. It has a traditional usage in philosophy that started in 1875 and was expanded by J. S. Mill (earlier, under a different term and C. D. Broad. It is this form of emergence that I am concerned with here. I distinguish it from uses like ‘computational emergence,’ which can be reduced to combinations of program steps, or its application to merely surprising new features that appear in complex combinations of parts. I will be concerned specifically with ontological emergence that has the logical properties required by Mill and Broad (though there might be some quibbling about the details of their views. I restrict myself to dynamical systems that are embodied in processes. Everything that we can interact with through sensation or action is either dynamical or can be understood in dynamical terms, so this covers all comprehensible forms of emergence in the strong (nonreducible sense I use. I will give general dynamical conditions that underlie the logical conditions traditionally assigned to emergence in nature.The advantage of this is that, though we cannot test logical conditions directly, we can test dynamical conditions. This gives us an empirical and realistic form of emergence, contrary those who say it is a matter of perspective.

  8. Modeling dynamic swarms

    KAUST Repository

    Ghanem, Bernard

    2013-01-01

    This paper proposes the problem of modeling video sequences of dynamic swarms (DSs). We define a DS as a large layout of stochastically repetitive spatial configurations of dynamic objects (swarm elements) whose motions exhibit local spatiotemporal interdependency and stationarity, i.e., the motions are similar in any small spatiotemporal neighborhood. Examples of DS abound in nature, e.g., herds of animals and flocks of birds. To capture the local spatiotemporal properties of the DS, we present a probabilistic model that learns both the spatial layout of swarm elements (based on low-level image segmentation) and their joint dynamics that are modeled as linear transformations. To this end, a spatiotemporal neighborhood is associated with each swarm element, in which local stationarity is enforced both spatially and temporally. We assume that the prior on the swarm dynamics is distributed according to an MRF in both space and time. Embedding this model in a MAP framework, we iterate between learning the spatial layout of the swarm and its dynamics. We learn the swarm transformations using ICM, which iterates between estimating these transformations and updating their distribution in the spatiotemporal neighborhoods. We demonstrate the validity of our method by conducting experiments on real and synthetic video sequences. Real sequences of birds, geese, robot swarms, and pedestrians evaluate the applicability of our model to real world data. © 2012 Elsevier Inc. All rights reserved.

  9. More dynamical supersymmetry breaking

    International Nuclear Information System (INIS)

    Csaki, C.; Randall, L.; Skiba, W.

    1996-01-01

    In this paper we introduce a new class of theories which dynamically break supersymmetry based on the gauge group SU(n) x SU(3) x U(1) for even n. These theories are interesting in that no dynamical superpotential is generated in the absence of perturbations. For the example SU(4) x SU(3) x U(1) we explicitly demonstrate that all flat directions can be lifted through a renormalizable superpotential and that supersymmetry is dynamically broken. We derive the exact superpotential for this theory, which exhibits new and interesting dynamical phenomena. For example, modifications to classical constraints can be field dependent. We also consider the generalization to SU(n) x SU(3) x U(1) models (with even n>4). We present a renormalizable superpotential which lifts all flat directions. Because SU(3) is not confining in the absence of perturbations, the analysis of supersymmetry breaking is very different in these theories from the n=4 example. When the SU(n) gauge group confines, the Yukawa couplings drive the SU(3) theory into a regime with a dynamically generated superpotential. By considering a simplified version of these theories we argue that supersymmetry is probably broken. (orig.)

  10. System dynamics with interaction discontinuity

    CERN Document Server

    Luo, Albert C J

    2015-01-01

    This book describes system dynamics with discontinuity caused by system interactions and presents the theory of flow singularity and switchability at the boundary in discontinuous dynamical systems. Based on such a theory, the authors address dynamics and motion mechanism of engineering discontinuous systems due to interaction. Stability and bifurcations of fixed points in nonlinear discrete dynamical systems are presented, and mapping dynamics are developed for analytical predictions of periodic motions in engineering discontinuous dynamical systems. Ultimately, the book provides an alternative way to discuss the periodic and chaotic behaviors in discontinuous dynamical systems.

  11. Vehicle dynamics theory and application

    CERN Document Server

    Jazar, Reza N

    2017-01-01

    This intermediate textbook is appropriate for students in vehicle dynamics courses, in their last year of undergraduate study or their first year of graduate study. It is also appropriate for mechanical engineers, automotive engineers, and researchers in the area of vehicle dynamics for continuing education or as a reference. It addresses fundamental and advanced topics, and a basic knowledge of kinematics and dynamics, as well as numerical methods, is expected. The contents are kept at a theoretical-practical level, with a strong emphasis on application. This third edition has been reduced by 25%, to allow for coverage over one semester, as opposed to the previous edition that needed two semesters for coverage. The textbook is composed of four parts: Vehicle Motion: covers tire dynamics, forward vehicle dynamics, and driveline dynamics Vehicle Kinematics: covers applied kinematics, applied mechanisms, steering dynamics, and suspension mechanisms Vehicle Dynamics: covers applied dynamics, vehicle planar dynam...

  12. Dynamics in geometrical confinement

    CERN Document Server

    Kremer, Friedrich

    2014-01-01

    This book describes the dynamics of low molecular weight and polymeric molecules when they are constrained under conditions of geometrical confinement. It covers geometrical confinement in different dimensionalities: (i) in nanometer thin layers or self supporting films (1-dimensional confinement) (ii) in pores or tubes with nanometric diameters (2-dimensional confinement) (iii) as micelles embedded in matrices (3-dimensional) or as nanodroplets.The dynamics under such conditions have been a much discussed and central topic in the focus of intense worldwide research activities within the last two decades. The present book discusses how the resulting molecular mobility is influenced by the subtle counterbalance between surface effects (typically slowing down molecular dynamics through attractive guest/host interactions) and confinement effects (typically increasing the mobility). It also explains how these influences can be modified and tuned, e.g. through appropriate surface coatings, film thicknesses or pore...

  13. Stochastic ice stream dynamics.

    Science.gov (United States)

    Mantelli, Elisa; Bertagni, Matteo Bernard; Ridolfi, Luca

    2016-08-09

    Ice streams are narrow corridors of fast-flowing ice that constitute the arterial drainage network of ice sheets. Therefore, changes in ice stream flow are key to understanding paleoclimate, sea level changes, and rapid disintegration of ice sheets during deglaciation. The dynamics of ice flow are tightly coupled to the climate system through atmospheric temperature and snow recharge, which are known exhibit stochastic variability. Here we focus on the interplay between stochastic climate forcing and ice stream temporal dynamics. Our work demonstrates that realistic climate fluctuations are able to (i) induce the coexistence of dynamic behaviors that would be incompatible in a purely deterministic system and (ii) drive ice stream flow away from the regime expected in a steady climate. We conclude that environmental noise appears to be crucial to interpreting the past behavior of ice sheets, as well as to predicting their future evolution.

  14. Introduction to dynamics

    CERN Document Server

    Pfeiffer, Friedrich

    2015-01-01

    This concise textbook for students preferably of a postgraduate level, but also for engineers in practice, contains the basic kinematical and kinetic structures of dynamics together with carefully selected applications. The book is a condensed introduction to the fundamental laws of kinematics and kinetics, on the most important principles of mechanics and presents the equations of motion in the form of Lagrange and Newton-Euler. Selected problems of linear and nonlinear dynamics are treated, as well as problems of vibration formation. The presented selection of topics gives a useful basis for stepping into more advanced problems of dynamics. The contents of this book represent the result of a regularly revised course, which has been and still is given for masters students at the Technische Universität München. .

  15. Dynamic Global Currency Hedging

    DEFF Research Database (Denmark)

    Christensen, Bent Jesper; Varneskov, Rasmus T.

    2016-01-01

    This paper proposes a model for discrete-time hedging based on continuous-time movements in portfolio and foreign currency exchange rate returns. In particular, the vector of optimal currency exposures is shown to be given by the negative realized regression coefficients from a one......-period conditional expectation of the intra-period quadratic covariation matrix for portfolio and foreign exchange rate returns. These are labelled the realized currency betas. The model, hence, facilitates dynamic hedging strategies that depend exclusively on the dynamic evolution of the ex-post quadratic...... covariation matrix. These hedging strategies are suggested implemented using modern, yet simple, non-parametric techniques to accurately measure and dynamically model historical quadratic covariation matrices. The empirical results from an extensive hedging exercise for equity investments illustrate...

  16. Butschli Dynamic Droplet System

    DEFF Research Database (Denmark)

    Armstrong, R.; Hanczyc, M.

    2013-01-01

    Dynamical oil-water systems such as droplets display lifelike properties and may lend themselves to chemical programming to perform useful work, specifically with respect to the built environment. We present Butschli water-in-oil droplets as a model for further investigation into the development...... reconstructed the Butschli system and observed its life span under a light microscope, observing chemical patterns and droplet behaviors in nearly three hundred replicate experiments. Self-organizing patterns were observed, and during this dynamic, embodied phase the droplets provided a means of introducing...... temporal and spatial order in the system with the potential for chemical programmability. The authors propose that the discrete formation of dynamic droplets, characterized by their lifelike behavior patterns, during a variable window of time (from 30 s to 30 min after the addition of alkaline water...

  17. Coherent dynamics in semiconductors

    DEFF Research Database (Denmark)

    Hvam, Jørn Märcher

    1998-01-01

    enhanced in quantum confined lower-dimensional systems, where exciton and biexciton effects dominate the spectra even at room temperature. The coherent dynamics of excitons are at modest densities well described by the optical Bloch equations and a number of the dynamical effects known from atomic......Ultrafast nonlinear optical spectroscopy is used to study the coherent dynamics of optically excited electron-hole pairs in semiconductors. Coulomb interaction implies that the optical inter-band transitions are dominated, at least at low temperatures, by excitonic effects. They are further...... and molecular systems are found and studied in the exciton-biexciton system of semiconductors. At densities where strong exciton interactions, or many-body effects, become dominant, the semiconductor Bloch equations present a more rigorous treatment of the phenomena Ultrafast degenerate four-wave mixing is used...

  18. Vorticity and vortex dynamics

    CERN Document Server

    Wu, Jie-Zhi; Zhou, M-D

    2006-01-01

    The importance of vorticity and vortex dynamics has now been well rec- nized at both fundamental and applied levels of ?uid dynamics, as already anticipatedbyTruesdellhalfcenturyagowhenhewrotethe?rstmonograph onthesubject, The Kinematics of Vorticity(1954);andasalsoevidencedby the appearance of several books on this ?eld in 1990s. The present book is characterizedbythefollowingfeatures: 1. A basic physical guide throughout the book. The material is directed by a basic observation on the splitting and coupling of two fundamental processes in ?uid motion, i.e., shearing (unique to ?uid) and compre- ing/expanding.Thevorticityplaysakeyroleintheformer,andavortex isnothingbuta?uidbodywithhighconcentrationofvorticitycompared to its surrounding ?uid. Thus, the vorticity and vortex dynamics is - cordinglyde?nedasthetheoryofshearingprocessanditscouplingwith compressing/expandingprocess. 2. A description of the vortex evolution following its entire life.Thisbegins from the generation of vorticity to the formation of thi...

  19. Lagrangian and Hamiltonian dynamics

    CERN Document Server

    Mann, Peter

    2018-01-01

    An introductory textbook exploring the subject of Lagrangian and Hamiltonian dynamics, with a relaxed and self-contained setting. Lagrangian and Hamiltonian dynamics is the continuation of Newton's classical physics into new formalisms, each highlighting novel aspects of mechanics that gradually build in complexity to form the basis for almost all of theoretical physics. Lagrangian and Hamiltonian dynamics also acts as a gateway to more abstract concepts routed in differential geometry and field theories and can be used to introduce these subject areas to newcomers. Journeying in a self-contained manner from the very basics, through the fundamentals and onwards to the cutting edge of the subject, along the way the reader is supported by all the necessary background mathematics, fully worked examples, thoughtful and vibrant illustrations as well as an informal narrative and numerous fresh, modern and inter-disciplinary applications. The book contains some unusual topics for a classical mechanics textbook. Mo...

  20. Predictability in community dynamics.

    Science.gov (United States)

    Blonder, Benjamin; Moulton, Derek E; Blois, Jessica; Enquist, Brian J; Graae, Bente J; Macias-Fauria, Marc; McGill, Brian; Nogué, Sandra; Ordonez, Alejandro; Sandel, Brody; Svenning, Jens-Christian

    2017-03-01

    The coupling between community composition and climate change spans a gradient from no lags to strong lags. The no-lag hypothesis is the foundation of many ecophysiological models, correlative species distribution modelling and climate reconstruction approaches. Simple lag hypotheses have become prominent in disequilibrium ecology, proposing that communities track climate change following a fixed function or with a time delay. However, more complex dynamics are possible and may lead to memory effects and alternate unstable states. We develop graphical and analytic methods for assessing these scenarios and show that these dynamics can appear in even simple models. The overall implications are that (1) complex community dynamics may be common and (2) detailed knowledge of past climate change and community states will often be necessary yet sometimes insufficient to make predictions of a community's future state. © 2017 John Wiley & Sons Ltd/CNRS.

  1. Fractional Dynamics and Control

    CERN Document Server

    Machado, José; Luo, Albert

    2012-01-01

    Fractional Dynamics and Control provides a comprehensive overview of recent advances in the areas of nonlinear dynamics, vibration and control with analytical, numerical, and experimental results. This book provides an overview of recent discoveries in fractional control, delves into fractional variational principles and differential equations, and applies advanced techniques in fractional calculus to solving complicated mathematical and physical problems.Finally, this book also discusses the role that fractional order modeling can play in complex systems for engineering and science. Discusses how fractional dynamics and control can be used to solve nonlinear science and complexity issues Shows how fractional differential equations and models can be used to solve turbulence and wave equations in mechanics and gravity theories and Schrodinger’s equation  Presents factional relaxation modeling of dielectric materials and wave equations for dielectrics  Develops new methods for control and synchronization of...

  2. Dynamical symmetries for fermions

    International Nuclear Information System (INIS)

    Guidry, M.

    1989-01-01

    An introduction is given to the Fermion Dynamical Symmetry Model (FDSM). The analytical symmetry limits of the model are then applied to the calculation of physical quantities such as ground-state masses and B(E 2 ) values in heavy nuclei. These comparisons with data provide strong support for a new principle of collective motion, the Dynamical Pauli Effect, and suggest that dynamical symmetries which properly account for the pauli principle are much more persistent in nuclear structure than the corresponding boson symmetries. Finally, we present an assessment of criticisms which have been voiced concerning the FDSM, and a discussion of new phenomena and ''exotic spectroscopy'' which may be suggested by the model. 14 refs., 8 figs., 4 tabs

  3. Conference on Multibody Dynamics

    CERN Document Server

    Multibody Dynamics : Computational Methods and Applications

    2014-01-01

    By having its origin in analytical and continuum mechanics, as well as in computer science and applied mathematics, multibody dynamics provides a basis for analysis and virtual prototyping of innovative applications in many fields of contemporary engineering. With the utilization of computational models and algorithms that classically belonged to different fields of applied science, multibody dynamics delivers reliable simulation platforms for diverse highly-developed industrial products such as vehicle and railway systems, aeronautical and space vehicles, robotic manipulators, smart structures, biomechanical applications and nano-technologies. The chapters of this volume are based on the revised and extended versions of the selected scientific papers from amongst 255 original contributions that have been accepted to be presented within the program of the distinguished international ECCOMAS conference. It reflects state-of-the-art in the advances of multibody dynamics, providing excellent insight in the recen...

  4. What are System Dynamics Insights?

    OpenAIRE

    Stave, K.; Zimmermann, N. S.; Kim, H.

    2016-01-01

    This paper explores the concept of system dynamics insights. In our field, the term “insight” is generally understood to mean dynamic insight, that is, a deep understanding about the relationship between structure and behavior. We argue this is only one aspect of the range of insights possible from system dynamics activities, and describe a broader range of potential system dynamics insights. We also propose an initial framework for discussion that relates different types of system dynamics a...

  5. Dynamically Assisted Schwinger Mechanism

    International Nuclear Information System (INIS)

    Schuetzhold, Ralf; Gies, Holger; Dunne, Gerald

    2008-01-01

    We study electron-positron pair creation from the Dirac vacuum induced by a strong and slowly varying electric field (Schwinger effect) which is superimposed by a weak and rapidly changing electromagnetic field (dynamical pair creation). In the subcritical regime where both mechanisms separately are strongly suppressed, their combined impact yields a pair creation rate which is dramatically enhanced. Intuitively speaking, the strong electric field lowers the threshold for dynamical particle creation--or, alternatively, the fast electromagnetic field generates additional seeds for the Schwinger mechanism. These findings could be relevant for planned ultrahigh intensity lasers

  6. Models for Dynamic Applications

    DEFF Research Database (Denmark)

    Sales-Cruz, Mauricio; Morales Rodriguez, Ricardo; Heitzig, Martina

    2011-01-01

    This chapter covers aspects of the dynamic modelling and simulation of several complex operations that include a controlled blending tank, a direct methanol fuel cell that incorporates a multiscale model, a fluidised bed reactor, a standard chemical reactor and finally a polymerisation reactor...... be applied to formulate, analyse and solve these dynamic problems and how in the case of the fuel cell problem the model consists of coupledmeso and micro scale models. It is shown how data flows are handled between the models and how the solution is obtained within the modelling environment....

  7. Dynamics of structures

    CERN Document Server

    Paultre, Patrick

    2013-01-01

    This book covers structural dynamics from a theoretical and algorithmic approach. It covers systems with both single and multiple degrees-of-freedom. Numerous case studies are given to provide the reader with a deeper insight into the practicalities of the area, and the solutions to these case studies are given in terms of real-time and frequency in both geometric and modal spaces. Emphasis is also given to the subject of seismic loading. The text is based on many lectures on the subject of structural dynamics given at numerous institutions and thus will be an accessible and practical aid to

  8. Dynamics in artifact ecologies

    DEFF Research Database (Denmark)

    Bødker, Susanne; Klokmose, Clemens Nylandsted

    2012-01-01

    We increasingly interact with multiple interactive artifacts with overlapping capabilities during our daily activities. It has previously been shown that the use of an interactive artifact cannot be understood in isolation, but artifacts must be understood as part of an artifact ecology, where...... artifacts influence the use of others. Understanding this interplay becomes more and more essential for interaction design as our artifact ecologies grow. This paper continues a recent discourse on artifact ecologies. Through interviews with iPhone users, we demonstrate that relationships between artifacts...... in artifact ecologies cannot be understood as static, instead they evolve dynamically over time. We provide activity theory-based concepts to explain these dynamics....

  9. Dynamic gamma knife radiosurgery

    International Nuclear Information System (INIS)

    Luan Shuang; Swanson, Nathan; Chen Zhe; Ma Lijun

    2009-01-01

    Gamma knife has been the treatment of choice for various brain tumors and functional disorders. Current gamma knife radiosurgery is planned in a 'ball-packing' approach and delivered in a 'step-and-shoot' manner, i.e. it aims to 'pack' the different sized spherical high-dose volumes (called 'shots') into a tumor volume. We have developed a dynamic scheme for gamma knife radiosurgery based on the concept of 'dose-painting' to take advantage of the new robotic patient positioning system on the latest Gamma Knife C(TM) and Perfexion(TM) units. In our scheme, the spherical high dose volume created by the gamma knife unit will be viewed as a 3D spherical 'paintbrush', and treatment planning reduces to finding the best route of this 'paintbrush' to 'paint' a 3D tumor volume. Under our dose-painting concept, gamma knife radiosurgery becomes dynamic, where the patient moves continuously under the robotic positioning system. We have implemented a fully automatic dynamic gamma knife radiosurgery treatment planning system, where the inverse planning problem is solved as a traveling salesman problem combined with constrained least-square optimizations. We have also carried out experimental studies of dynamic gamma knife radiosurgery and showed the following. (1) Dynamic gamma knife radiosurgery is ideally suited for fully automatic inverse planning, where high quality radiosurgery plans can be obtained in minutes of computation. (2) Dynamic radiosurgery plans are more conformal than step-and-shoot plans and can maintain a steep dose gradient (around 13% per mm) between the target tumor volume and the surrounding critical structures. (3) It is possible to prescribe multiple isodose lines with dynamic gamma knife radiosurgery, so that the treatment can cover the periphery of the target volume while escalating the dose for high tumor burden regions. (4) With dynamic gamma knife radiosurgery, one can obtain a family of plans representing a tradeoff between the delivery time and

  10. Stochastic Switching Dynamics

    DEFF Research Database (Denmark)

    Simonsen, Maria

    This thesis treats stochastic systems with switching dynamics. Models with these characteristics are studied from several perspectives. Initially in a simple framework given in the form of stochastic differential equations and, later, in an extended form which fits into the framework of sliding...... mode control. It is investigated how to understand and interpret solutions to models of switched systems, which are exposed to discontinuous dynamics and uncertainties (primarily) in the form of white noise. The goal is to gain knowledge about the performance of the system by interpreting the solution...

  11. Dynamics of Catalyst Nanoparticles

    DEFF Research Database (Denmark)

    Hansen, Thomas Willum; Cavalca, Filippo; Wagner, Jakob Birkedal

    and pharmaceuticals, and the cleanup of exhaust from automobiles and stationary power plants. Sintering, or thermal deactivation, is an important mechanism for the loss of catalyst activity. In order to initiate a systematic study of the dynamics and sintering of nanoparticles, various catalytic systems have been...... under gas exposure, dynamic phenomena such as sintering and growth can be observed with sub-Ångstrøm resolution. Metal nanoparticles contain the active sites in heterogeneous catalysts, which are important for many industrial applications including the production of clean fuels, chemicals...

  12. Safe Dynamic Multiple Inheritance

    DEFF Research Database (Denmark)

    Ernst, Erik

    2002-01-01

    Multiple inheritance and similar mechanisms are usually only supported at compile time in statically typed languages. Nevertheless, dynamic multiple inheritance would be very useful in the development of complex systems, because it allows the creation of many related classes without an explosion...... in the size and level of redundancy in the source code. In fact, dynamic multiple inheritance is already available. The language gbeta is statically typed and has supported run-time combination of classes and methods since 1997, by means of the combination operator '&'. However, with certain combinations...

  13. Fundamental composite electroweak dynamics

    DEFF Research Database (Denmark)

    Arbey, Alexandre; Cacciapaglia, Giacomo; Cai, Haiying

    2017-01-01

    Using the recent joint results from the ATLAS and CMS collaborations on the Higgs boson, we determine the current status of composite electroweak dynamics models based on the expected scalar sector. Our analysis can be used as a minimal template for a wider class of models between the two limitin...... space at the effective Lagrangian level. We show that a wide class of models of fundamental composite electroweak dynamics are still compatible with the present constraints. The results are relevant for the ongoing and future searches at the Large Hadron Collider....

  14. Introduction to cluster dynamics

    CERN Document Server

    Reinhard, Paul-Gerhard

    2008-01-01

    Clusters as mesoscopic particles represent an intermediate state of matter between single atoms and solid material. The tendency to miniaturise technical objects requires knowledge about systems which contain a ""small"" number of atoms or molecules only. This is all the more true for dynamical aspects, particularly in relation to the qick development of laser technology and femtosecond spectroscopy. Here, for the first time is a highly qualitative introduction to cluster physics. With its emphasis on cluster dynamics, this will be vital to everyone involved in this interdisciplinary subje

  15. Spectrally accurate contour dynamics

    International Nuclear Information System (INIS)

    Van Buskirk, R.D.; Marcus, P.S.

    1994-01-01

    We present an exponentially accurate boundary integral method for calculation the equilibria and dynamics of piece-wise constant distributions of potential vorticity. The method represents contours of potential vorticity as a spectral sum and solves the Biot-Savart equation for the velocity by spectrally evaluating a desingularized contour integral. We use the technique in both an initial-value code and a newton continuation method. Our methods are tested by comparing the numerical solutions with known analytic results, and it is shown that for the same amount of computational work our spectral methods are more accurate than other contour dynamics methods currently in use

  16. DYNAMIC LOAD DAMPER MODELING

    Directory of Open Access Journals (Sweden)

    Loktev Aleksey Alekseevich

    2013-01-01

    Full Text Available The authors present their findings associated with their modeling of a dynamic load damper. According to the authors, the damper is to be installed onto a structure or its element that may be exposed to impact, vibration or any other dynamic loading. The damper is composed of paralleled or consecutively connected viscous and elastic elements. The authors study the influence of viscosity and elasticity parameters of the damper produced onto the regular displacement of points of the structure to be protected and onto the regular acceleration transmitted immediately from the damper to the elements positioned below it.

  17. Fluid Dynamics for Physicists

    Science.gov (United States)

    Faber, T. E.

    1995-08-01

    This textbook provides an accessible and comprehensive account of fluid dynamics that emphasizes fundamental physical principles and stresses connections with other branches of physics. Beginning with a basic introduction, the book goes on to cover many topics not typically treated in texts, such as compressible flow and shock waves, sound attenuation and bulk viscosity, solitary waves and ship waves, thermal convection, instabilities, turbulence, and the behavior of anisotropic, non-Newtonian and quantum fluids. Undergraduate or graduate students in physics or engineering who are taking courses in fluid dynamics will find this book invaluable.

  18. Maya Studio Projects Dynamics

    CERN Document Server

    Palamar, Todd

    2009-01-01

    The only hands-on book devoted to mastering Maya's dynamics tools for water, wind, and fire. In the world of animation, the ability to create realistic water, wind, and fire effects is key. Autodesk Maya software includes powerful dynamics tools that have been used to design breathtaking effects for movies, games, commercials, and short films. This professional guide teaches you the primary techniques you need to make the most of Maya's toolkit, so you'll soon be creating water that ripples, gusting winds and gentle breezes, and flickering fires the way Hollywood pros do. The one-of-a-kind boo

  19. Substructured multibody molecular dynamics.

    Energy Technology Data Exchange (ETDEWEB)

    Grest, Gary Stephen; Stevens, Mark Jackson; Plimpton, Steven James; Woolf, Thomas B. (Johns Hopkins University, Baltimore, MD); Lehoucq, Richard B.; Crozier, Paul Stewart; Ismail, Ahmed E.; Mukherjee, Rudranarayan M. (Rensselaer Polytechnic Institute, Troy, NY); Draganescu, Andrei I.

    2006-11-01

    We have enhanced our parallel molecular dynamics (MD) simulation software LAMMPS (Large-scale Atomic/Molecular Massively Parallel Simulator, lammps.sandia.gov) to include many new features for accelerated simulation including articulated rigid body dynamics via coupling to the Rensselaer Polytechnic Institute code POEMS (Parallelizable Open-source Efficient Multibody Software). We use new features of the LAMMPS software package to investigate rhodopsin photoisomerization, and water model surface tension and capillary waves at the vapor-liquid interface. Finally, we motivate the recipes of MD for practitioners and researchers in numerical analysis and computational mechanics.

  20. Complexified dynamical systems

    International Nuclear Information System (INIS)

    Bender, Carl M; Holm, Darryl D; Hook, Daniel W

    2007-01-01

    Many dynamical systems, such as the Lotka-Volterra predator-prey model and the Euler equations for the free rotation of a rigid body, are PT symmetric. The standard and well-known real solutions to such dynamical systems constitute an infinitessimal subclass of the full set of complex solutions. This paper examines a subset of the complex solutions that contains the real solutions, namely those having PT symmetry. The condition of PT symmetry selects out complex solutions that are periodic. (fast track communication)

  1. Dynamic gamma knife radiosurgery

    Energy Technology Data Exchange (ETDEWEB)

    Luan Shuang; Swanson, Nathan; Chen Zhe [Department of Computer Science, University of New Mexico, Albuquerque, NM 87131 (United States); Ma Lijun [Department of Radiation Oncology, University of California San Francisco, San Francisco, CA 94143 (United States)], E-mail: sluan@cs.unm.edu, E-mail: nate@cs.unm.edu, E-mail: zchen@cs.unm.edu, E-mail: lijunma@radonc.ucsf.edu

    2009-03-21

    Gamma knife has been the treatment of choice for various brain tumors and functional disorders. Current gamma knife radiosurgery is planned in a 'ball-packing' approach and delivered in a 'step-and-shoot' manner, i.e. it aims to 'pack' the different sized spherical high-dose volumes (called 'shots') into a tumor volume. We have developed a dynamic scheme for gamma knife radiosurgery based on the concept of 'dose-painting' to take advantage of the new robotic patient positioning system on the latest Gamma Knife C(TM) and Perfexion(TM) units. In our scheme, the spherical high dose volume created by the gamma knife unit will be viewed as a 3D spherical 'paintbrush', and treatment planning reduces to finding the best route of this 'paintbrush' to 'paint' a 3D tumor volume. Under our dose-painting concept, gamma knife radiosurgery becomes dynamic, where the patient moves continuously under the robotic positioning system. We have implemented a fully automatic dynamic gamma knife radiosurgery treatment planning system, where the inverse planning problem is solved as a traveling salesman problem combined with constrained least-square optimizations. We have also carried out experimental studies of dynamic gamma knife radiosurgery and showed the following. (1) Dynamic gamma knife radiosurgery is ideally suited for fully automatic inverse planning, where high quality radiosurgery plans can be obtained in minutes of computation. (2) Dynamic radiosurgery plans are more conformal than step-and-shoot plans and can maintain a steep dose gradient (around 13% per mm) between the target tumor volume and the surrounding critical structures. (3) It is possible to prescribe multiple isodose lines with dynamic gamma knife radiosurgery, so that the treatment can cover the periphery of the target volume while escalating the dose for high tumor burden regions. (4) With dynamic gamma knife radiosurgery, one can

  2. Dynamics on Lorentz manifolds

    CERN Document Server

    Adams, Scot

    2001-01-01

    Within the general framework of the dynamics of "large" groups on geometric spaces, the focus is on the types of groups that can act in complicated ways on Lorentz manifolds, and on the structure of the resulting manifolds and actions. This particular area of dynamics is an active one, and not all the results are in their final form. However, at this point, a great deal can be said about the particular Lie groups that come up in this context. It is impressive that, even assuming very weak recurrence of the action, the list of possible groups is quite restricted. For the most complicated of the

  3. Nonuniversal disordered Glauber dynamics.

    Science.gov (United States)

    Grynberg, Marcelo D; Stinchcombe, Robin B

    2013-06-01

    We consider the one-dimensional Glauber dynamics with coupling disorder in terms of bilinear fermion Hamiltonians. Dynamic exponents embodied in the spectrum gap of these latter are evaluated numerically by averaging over both binary and Gaussian disorder realizations. In the first case, these exponents are found to follow the nonuniversal values of those of plain dimerized chains. In the second situation their values are still nonuniversal and subdiffusive below a critical variance above which, however, the relaxation time is suggested to grow as a stretched exponential of the equilibrium correlation length.

  4. Principles of dynamics

    CERN Document Server

    Hill, Rodney

    2013-01-01

    Principles of Dynamics presents classical dynamics primarily as an exemplar of scientific theory and method. This book is divided into three major parts concerned with gravitational theory of planetary systems; general principles of the foundations of mechanics; and general motion of a rigid body. Some of the specific topics covered are Keplerian Laws of Planetary Motion; gravitational potential and potential energy; and fields of axisymmetric bodies. The principles of work and energy, fictitious body-forces, and inertial mass are also looked into. Other specific topics examined are kinematics

  5. Dynamic planar embeddings of dynamic graphs

    DEFF Research Database (Denmark)

    Holm, Jacob; Rotenberg, Eva

    2015-01-01

    -flip-linkable(u, v) providing a suggestion for a flip that will make them linkable if one exists. We will support all updates and queries in O(log2 n) time. Our time bounds match those of Italiano et al. for a static (flipless) embedding of a dynamic graph. Our new algorithm is simpler, exploiting...... that the complement of a spanning tree of a connected plane graph is a spanning tree of the dual graph. The primal and dual trees are interpreted as having the same Euler tour, and a main idea of the new algorithm is an elegant interaction between top trees over the two trees via their common Euler tour....

  6. Dynamic planar embeddings of dynamic graphs

    DEFF Research Database (Denmark)

    Holm, Jacob; Rotenberg, Eva

    2017-01-01

    query, one-flip- linkable(u,v) providing a suggestion for a flip that will make them linkable if one exists. We support all updates and queries in O(log 2 n) time. Our time bounds match those of Italiano et al. for a static (flipless) embedding of a dynamic graph. Our new algorithm is simpler......, exploiting that the complement of a spanning tree of a connected plane graph is a spanning tree of the dual graph. The primal and dual trees are interpreted as having the same Euler tour, and a main idea of the new algorithm is an elegant interaction between top trees over the two trees via their common...

  7. Dynamic Analysis of a Pendulum Dynamic Automatic Balancer

    Directory of Open Access Journals (Sweden)

    Jin-Seung Sohn

    2007-01-01

    Full Text Available The automatic dynamic balancer is a device to reduce the vibration from unbalanced mass of rotors. Instead of considering prevailing ball automatic dynamic balancer, pendulum automatic dynamic balancer is analyzed. For the analysis of dynamic stability and behavior, the nonlinear equations of motion for a system are derived with respect to polar coordinates by the Lagrange's equations. The perturbation method is applied to investigate the dynamic behavior of the system around the equilibrium position. Based on the linearized equations, the dynamic stability of the system around the equilibrium positions is investigated by the eigenvalue analysis.

  8. Dynamic Systems and Software

    DEFF Research Database (Denmark)

    Thomsen, Per Grove

    1996-01-01

    A one-dimensional model with axial discretization of engine components has been formulated using tha balance equations for mass energy and momentum and the ideal gas equation of state. ODE's that govern the dynamic behaviour of the regenerator matrix temperatures are included in the model. Known...

  9. PELE fragmentation dynamics

    NARCIS (Netherlands)

    Verreault, J.; Hinsberg, N.P. van; Abadjieva, E.

    2013-01-01

    An analytical model that describes the PELE fragmentation dynamics is presented and compared with experimental results from literature. The model accounts for strong shock effects and detailed interactions taking place between the filling – the inner core of the ammunition – and the target

  10. Rf quadrupole beam dynamics

    International Nuclear Information System (INIS)

    Stokes, R.H.; Crandall, K.R.; Stovall, J.E.; Swenson, D.A.

    1979-01-01

    A method has been developed to analyze the beam dynamics of the radiofrequency quadrupole accelerating structure. Calculations show that this structure can accept a dc beam at low velocity, bunch it with high capture efficiency, and accelerate it to a velocity suitable for injection into a drift tube linac

  11. Dynamics of Information Systems

    CERN Document Server

    Hirsch, Michael J; Murphey, Robert

    2010-01-01

    Our understanding of information and information dynamics has outgrown classical information theory. This book presents the research explaining the importance of information in the evolution of a distributed or networked system. It presents techniques for measuring the value or significance of information within the context of a system

  12. Studies in Chemical Dynamics

    International Nuclear Information System (INIS)

    Rabitz, Herschel; Ho, Tak-San

    2003-01-01

    This final report draws together the research carried from February, 1986 through January, 2003 concerning a series of topics in chemical dynamics. The specific areas of study include molecular collisions, chemical kinetics, data inversion to extract potential energy surfaces, and model reduction of complex kinetic systems

  13. Pathwise dynamic programming

    NARCIS (Netherlands)

    Bender, Christian; Gärtner, Christian; Schweizer, Nikolaus

    2017-01-01

    We present a novel method for deriving tight Monte Carlo confidence intervals for solutions of stochastic dynamic programming equations. Taking some approximate solution to the equation as an input, we construct pathwise recursions with a known bias. Suitably coupling the recursions for lower and

  14. Structural dynamics in FBR

    International Nuclear Information System (INIS)

    Bhoje, S.B.

    2003-01-01

    In view of thin walled large diameter shell structures with associated fluid effects, structural dynamics problems are very critical in a fast breeder reactor. Structural characteristics and consequent structural dynamics problems in typical pool type Fast Breeder Reactor are highlighted. A few important structural dynamics problems are pump induced as well as flow induced vibrations, seismic excitations, pressure transients in the intermediate heat exchangers and pipings due to a large sodium water reaction in the steam generator, and core disruptive accident loadings. The vibration problems which call for identification of excitation forces, formulation of special governing equations and detailed analysis with fluid structure interaction and sloshing effects, particularly for the components such as PSP, inner vessel, CP, CSRDM and TB are elaborated. Seismic design issues are presented in a comprehensive way. Other transient loadings which are specific to FBR, resulting from sodium-water reaction and core disruptive accident are highlighted. A few important results of theoretical as well as experimental works carried out for 500 MWe Prototype Fast Breeder Reactor (PFBR), in the domain of structural dynamics are presented. (author)

  15. Some Dynamics of Authorship.

    Science.gov (United States)

    Dunkin, Mick

    1992-01-01

    A study of the relationship between faculty publishing and career advancement at the University of Sydney (Australia) controlled for both gender and discipline. Results revealed some previously unseen dynamics of authorship, bringing into question common assumptions about solo vs. multiple authors and order of author names. Some discipline-related…

  16. Functional System Dynamics

    NARCIS (Netherlands)

    Ligterink, N.E.

    2007-01-01

    Functional system dynamics is the analysis, modelling, and simulation of continuous systems usually described by partial differential equations. From the infinite degrees of freedom of such systems only a finite number of relevant variables have to be chosen for a practical model description. The

  17. Dynamics of homogeneous nucleation

    DEFF Research Database (Denmark)

    Toxværd, Søren

    2015-01-01

    The classical nucleation theory for homogeneous nucleation is formulated as a theory for a density fluctuation in a supersaturated gas at a given temperature. But molecular dynamics simulations reveal that it is small cold clusters which initiates the nucleation. The temperature in the nucleating...

  18. ESSENTIAL DYNAMICS OF PROTEINS

    NARCIS (Netherlands)

    AMADEI, A; LINSSEN, ABM; BERENDSEN, HJC

    1993-01-01

    Analysis of extended molecular dynamics (MD) simulations of lysozyme in vacuo and in aqueous solution reveals that it is possible to separate the configurational space into two subspaces: (1) an ''essential'' subspace containing only a few degrees of freedom in which anharmonic motion occurs that

  19. Antiparallel Dynamic Covalent Chemistries

    NARCIS (Netherlands)

    Matysiak, Bartosz M.; Nowak, Piotr; Cvrtila, Ivica; Pappas, Charalampos G.; Liu, Bin; Komaromy, David; Otto, Sijbren

    2017-01-01

    The ability to design reaction networks with high, but addressable complexity is a necessary prerequisite to make advanced functional chemical systems. Dynamic combinatorial chemistry has, proven to be a useful tool in achieving complexity, however with some limitations in controlling it. Herein we

  20. Dynamics of human movement

    NARCIS (Netherlands)

    Koopman, Hubertus F.J.M.

    2010-01-01

    The part of (bio)mechanics that studies the interaction of forces on the human skeletal system and its effect on the resulting movement is called rigid body dynamics. Some basic concepts are presented: A mathematical formulation to describe human movement and how this relates on the mechanical loads