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Sample records for craniovertebral junction anomalies

  1. RADIOLOGICAL EVALUATION OF CRANIOVERTEBRAL JUNCTION ANOMALIES

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    Joji Reddy

    2015-08-01

    Full Text Available INTRODUCTION: Detailed discussions of the CVJ are conspicuously absent in many standard textbooks and chapters addressing the skull or cervical spine, since it lies in between these regions . CVJ anomalies are common in India subcontinent. OBJECTIVES : To outline the normal anatomy and various abnormalities of craniovertebral junction. To evaluate the most common developmental and acquired craniovertebral junction abnormalities . CRANIOMETRY AND DIAGNOSIS: Radiological evaluation of CVJ requir es identification of only a few anatomic structures. Over the years multiple lines , planes and angles have been described for assessment of CVJ relationship , initially with radiography and later with polytomography. Two lines have remained particularly use ful for evaluation of CVJ relationship with virtually any imaging modality: the chamberlain`s line and weckenheim ’ s clivus base line . Two angles also continue to be useful: the welcher basal angle and atlanto occipital joint axis angle. PATIENTS AND METHOD S: The prospective study of craniovertebral junction anomalies was carried out at Kurnool medical college , Governament general hospital Kurnool from NOV 2012 to AUG 2014. The patients are subjected to clinical evaluation and radiological evaluation. OBSERV ATIONS AND RESULTS : In our study there is male predominance with male to female ratio of 2:1 . Majority of patients are in the age group of 11 - 40 (73.26%. The commonest symptom seen is weakness of extremities ( 70% with associated numbness (50%. On clinica l examination pyramidal tract involvement noticed in 70% of cases. Basilar invagination is the most common followed by Atlantoocoipital assimilation (40% and AAD (30% . CONCLUSION : Computed tomography and magnetic resonance imaging are invalvable adjuncts to the plain radiographs in the evaluation of the craniovertebral junction anomalies. Chamberlain’s line and McGregor line are the most commonly applied craniometric measurements

  2. Magnetic resonance imaging in craniovertebral junction anomaly

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    Tada, Shimpei; Hata, Yuichi; Miyamoto, Yukio

    1985-03-01

    Materials consisted of 6 cases with occipitalization of the atlas, (4 of them complicated by basilar impression), 7 with basilar impression, one with hypoplasia of the atlas and C2-3 fusion, and one with os odontoideum. Basal angles after Welcker were all more than 130 in contrast to 118-138 (127 an average) in control group. Basal angle more than 140 denoted platybasia. Syringomyelia was seen in 7 of all 15 cases and 4 of 5 cases with platybasia. Chiari malformation was seen in 9 of all 15 cases and 4 of 5 with platybasia. Basal angles were closely related to craniovertebral junction bone anomaly, syringomyelia, and Chiari malformation. (author).

  3. Acromesomelic dysplasia (Marotaeux type associated with craniovertebral junction anomaly: A report of a rare case and review of literature

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    Jayesh C Sardhara

    2014-01-01

    Full Text Available Acromesomelic dysplasia Maroteaux type (AMDM is a rare autosomal recessive osteochondrodysplasia. The responsible gene, AMDM gene, in human beings, has been mapped on 9p13-q12 chromosome by homozygous mapping and pathogenic mutation was later identified in natriuretic receptor B (NPR-B which has been implicated in the regulation of skeletal growth. Till now, around 40 to 50 cases of AMDM have been described in the world literature. Association of the congenital craniovertebral (CV junction anomaly has not been reported. Here we are presenting a case of AMDM, with CV junction anomaly. A 10-year boy presented with short stature (122 cm with short distal limbs, symptomatic for thoracic kyphoscoliosis with back pain. On examination there were no neurological deficits. On radiological investigation, he was found to have short and broad phalanges and toes, thoracic kyphoscoliosis, abnormal pelvic ring, mild ventriculomegaly, cervical syringomyelia and tonsillar descent below foramen magnum, hydrocephalus, os odontoideum with Klippel-Feil anomaly. This was diagnosed as AMDM with congenital os odontoideum, Klippel-Feil anomaly with Arnold-Chiari malformation (ACM type-1. The patient underwent posterior fossa decompression by removal of foramen magnum ring along with C1 arch for ACM type-1. Kyphosis was left for conservative treatment till further observation and required orthopedic correction in his further age. To the best of our knowledge this is a very rare entity of AMDM with congenital CV junction anomaly.

  4. Knock and Drill Technique: A Simple Tips for the Instrumentation in Complex Craniovertebral Junction Anomalies without using Fluoroscopy

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    Srivastava, Arun; Sardhara, Jayesh; Behari, Sanjay; Pavaman, Sindgikar; Joseph, Jeena; Das, Kuntal; Mehrotra, Anant; Jaiswal, Awadhesh K.; Bhaishora, Kamlesh

    2017-01-01

    Context: Existence of complex variable bony and vertebral artery (VA) anomalies at craniovertebral junction (CVJ) in subset of complex CVJ anomalies demands individualized instrumentation policy and placing screws in each bone requires strategic preoperative planning and intraoperative skills. Aim: To evaluate the clinical accuracy of knock and drill (K and D) technique for the screw placement in complex CVJ anomalies. Settings and Design: Prospective study and operative technical note. Materials and Methods: Totally 36 consecutive patients (16 - pediatrics, 20 - adult patients) of complex CVJ: Complete/partial occipitalized C1 vertebra; at least one hypoplastic (C1/C2) articular mass, rotational component, and variations in the third part of VA were included in this study. Preoperative detail computed tomography (CT) CT CVJ with three-dimensional reconstruction was done for the assessment of CVJ anatomy and facet joint orientation. The accuracy of novel technique was assessed with postoperative CT to evaluate cortical breach in between 5th and 7th postoperative day in all the patients. All patients were underwent clinico-radiological evaluation at 6-month follow-up. Results: Totally 144 screws were placed using K and D technique (pediatric group - 64 screws, adult patients - 80 screws). Total of 12 screws were placed in C1 lateral mass in both age group without any bony cortical breach and complication. Sixteen C2 pedicle screws and 12 C2 pars screw in pediatrics and 18 C2 pedicle screws in adult patients were placed without any bony breach or VA injury. Out of thirty subaxial lateral mass screws in pediatric group, the bony breach was encountered with one screw (3.3%). Total of 38 C2 pars screws was placed in adult group in which bony breach along with VA injury was encounter with 1screw (2.6%). Conclusion: A simple technique of K and D for placing a screw increases the accuracy and spectrum of bony purchase and has the potential to reduce the complication in

  5. Craniovertebral junction stenosis in Lenz-Majewski syndrome

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    Mizuguchi, Koichi; Ishigro, Akira [National Center for Child Health and Development, Department of General Pediatrics and Interdisciplinary Medicine, Setagaya-ku, Tokyo (Japan); Miyazaki, Osamu [National Center for Child Health and Development, Department of Radiology, Tokyo (Japan); Nishimura, Gen [Tokyo Metropolitan Children' s Medical Center, Department of Pediatric Imaging, Tokyo (Japan)

    2015-09-15

    We report a girl with Lenz-Majewski syndrome associated with craniovertebral junction stenosis that led to communicating hydrocephalus and cervical myelopathy. The life-threatening complication was related to progressive craniovertebral hyperostosis that rapidly exacerbated during early childhood. Despite initial success of surgical intervention at 2 years of age, she developed apneic spells and died suddenly at age 5 years. Close monitoring for craniovertebral junction stenosis is essential to reduce morbidity and mortality in children with Lenz-Majewski syndrome. (orig.)

  6. Craniovertebral junction stenosis in Lenz-Majewski syndrome.

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    Mizuguchi, Koichi; Miyazaki, Osamu; Nishimura, Gen; Ishigro, Akira

    2015-09-01

    We report a girl with Lenz-Majewski syndrome associated with craniovertebral junction stenosis that led to communicating hydrocephalus and cervical myelopathy. The life-threatening complication was related to progressive craniovertebral hyperostosis that rapidly exacerbated during early childhood. Despite initial success of surgical intervention at 2 years of age, she developed apneic spells and died suddenly at age 5 years. Close monitoring for craniovertebral junction stenosis is essential to reduce morbidity and mortality in children with Lenz-Majewski syndrome.

  7. Craniovertebral Junction Instability in the Setting of Chiari I Malformation.

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    Goldstein, Hannah E; Anderson, Richard C E

    2015-10-01

    This article addresses the key features, clinical presentation, and radiographic findings associated with craniovertebral junction instability in the setting of Chiari I malformation. It further discusses surgical technique for treating patients with Chiari I malformation with concomitant craniovertebral junction instability, focusing on modern posterior rigid instrumentation and fusion techniques.

  8. Anatomy and biomechanics of the craniovertebral junction.

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    Lopez, Alejandro J; Scheer, Justin K; Leibl, Kayla E; Smith, Zachary A; Dlouhy, Brian J; Dahdaleh, Nader S

    2015-04-01

    The craniovertebral junction (CVJ) has unique anatomical structures that separate it from the subaxial cervical spine. In addition to housing vital neural and vascular structures, the majority of cranial flexion, extension, and axial rotation is accomplished at the CVJ. A complex combination of osseous and ligamentous supports allow for stability despite a large degree of motion. An understanding of anatomy and biomechanics is essential to effectively evaluate and address the various pathological processes that may affect this region. Therefore, the authors present an up-to-date narrative review of CVJ anatomy, normal and pathological biomechanics, and fixation techniques.

  9. Top 50 most-cited articles on craniovertebral junction surgery.

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    Alan, Nima; Cohen, Jonathan Andrew; Zhou, James; Pease, Matthew; Kanter, Adam S; Okonkwo, David O; Hamilton, David Kojo

    2017-01-01

    Craniovertebral junction is a complex anatomical location posing unique challenges to the surgical management of its pathologies. We aimed to identify the fifty most-cited articles that are dedicated to this field. A keyword search using the Thomson Reuters Web of Knowledge was conducted to identify articles relevant to the field of craniovertebral junction surgery. The articles were reviewed based on title, abstract, and methods, if necessary, and then ranked based on the total number of citations to identify the fifty most-cited articles. Characteristics of the articles were determined and analyzed. The earliest top-cited article was published in 1948. When stratified by decade, 1990s was the most productive with 16 articles. The most-cited article was by Anderson and Dalonzo on a classification of odontoid fractures. By citation rate, the most-cited article was by Herms and Melcher who described Goel's technique of atlantoaxial fixation using C1 lateral mass screws and C2 pedicle screws with rod fixation. Atlantoaxial fixation was the most common topic. The United States, Barrow Neurological Institute, and VH Sonntag were the most represented country, institute, and author, respectively. The significant majority of articles were designed as case series providing level IV evidence. Using citation analysis, we have provided a list of the most-cited articles representing important contributions of various authors from many institutions across the world to the field of craniovertebral junction surgery.

  10. Combined transnasal and transoral endoscopic approaches to the craniovertebral junction

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    I H El-Sayed

    2010-01-01

    Full Text Available Objectives: To describe and evaluate a new technique of a combined endoscope-assisted transnasal and transoral approach to decompress the craniovertebral junction. Materials and Methods: A retrospective cohort of patients requiring an anterior decompression at the craniovertebral junction over a 12-month period was studied. Eleven patients were identified and included in the study. Eight of the patients had an endoscopic approach [endonasal (2, endooral (2, and combined (4]. Four of the 8 patients in the endoscopic group had a prior open transoral procedure at other institutions. These 8 patients were compared with a contemporary group of 3 patients who had an open, transoral-transpalatal approach. Charts, radiographic images, and pathologic diagnosis were reviewed. We evaluated the following issues: airway obstruction, dysphagia, velopharyngeal insufficiency (VPI, length of hospital stay (LOS, adequate decompression, and the need for revision surgery. Results: Adequate anterior decompression was achieved in all the patients. The endoscopic cohort had a reduced LOS (P = 0.014, reduced need for prolonged intubation/tracheotomy (P =0.024 and a trend toward reduced VPI (P = 0.061 when compared with the open surgery group. None of the patients required a revision surgery. Conclusion: Proper choice of endoscopic transnasal, transoral, or combined approaches allows anterior decompression at the craniovertebral junction, while avoiding the need to split the palate. A combined transnasal-transoral approach appears to reduce procedure-related morbidity compared with open, transoral, and transpalatal surgeries.

  11. Top 50 most-cited articles on craniovertebral junction surgery

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    Alan, Nima; Cohen, Jonathan Andrew; Zhou, James; Pease, Matthew; Kanter, Adam S; Okonkwo, David O; Hamilton, David Kojo

    2017-01-01

    Background: Craniovertebral junction is a complex anatomical location posing unique challenges to the surgical management of its pathologies. We aimed to identify the fifty most-cited articles that are dedicated to this field. Methods: A keyword search using the Thomson Reuters Web of Knowledge was conducted to identify articles relevant to the field of craniovertebral junction surgery. The articles were reviewed based on title, abstract, and methods, if necessary, and then ranked based on the total number of citations to identify the fifty most-cited articles. Characteristics of the articles were determined and analyzed. Results: The earliest top-cited article was published in 1948. When stratified by decade, 1990s was the most productive with 16 articles. The most-cited article was by Anderson and Dalonzo on a classification of odontoid fractures. By citation rate, the most-cited article was by Herms and Melcher who described Goel's technique of atlantoaxial fixation using C1 lateral mass screws and C2 pedicle screws with rod fixation. Atlantoaxial fixation was the most common topic. The United States, Barrow Neurological Institute, and VH Sonntag were the most represented country, institute, and author, respectively. The significant majority of articles were designed as case series providing level IV evidence. Conclusion: Using citation analysis, we have provided a list of the most-cited articles representing important contributions of various authors from many institutions across the world to the field of craniovertebral junction surgery. PMID:28250633

  12. Acute obstructive hydrocephalus complicating decompression surgery of the craniovertebral junction

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    Ohya, Junichi; Chikuda, Hirotaka; Nakatomi, Hirofumi; Sakamoto, Ryuji; Saito, Nobuhito; Tanaka, Sakae

    2016-01-01

    Obstructive hydrocephalus has been described as a rare complication following foramen magnum decompression for Chiari malformation. However, there are few reports of obstructive hydrocephalus after spinal surgery for other pathologies of the craniovertebral junction (CVJ). The authors herein report a 52-year-old female with achondroplasia presenting with an 8-month history of myelopathy due to spinal cord compression at CVJ. She underwent resection of the C1 posterior arch and part of the edge of the occipital bone. A computed tomography (CT) scan obtained 1-week after the surgery revealed bilateral infratentorial fluid collection. The patient was first managed conservatively; however, on the 17th day, her consciousness level showed sudden deterioration. Emergency CT demonstrated marked hydrocephalus due to obstruction of the cerebral aqueduct. Acute obstructive hydrocephalus can occur late after decompression surgery at the CVJ, and thus should be included in the differential diagnosis of a deteriorating mental status. PMID:27366268

  13. Dynamic imaging of disorders at craniovertebral junction using fast gradient echo imaging

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    Nambu, Toshikazu; Miyasaka, Kazuo [Hokkaido Univ., Sapporo (Japan). School of Medicine; Yamamoto, Isao; Itoh, Hajime

    1995-01-01

    We have investigated the usefulness of Turbo-FLASH MR imaging in the dynamic evaluations of the disorders at craniovertebral junction. Using this fast scan program, serial fifteen dynamic images of the midline cervical plane could be obtained in 53 seconds, while the patient had very slow autonomous flexion-extension movement. Twelve cases including atlanto-axial dislocation, os odontoideum and Chiari malformation were investigated. The dynamic images could demonstrate findings of upper spinal cord compression which correlated well to the static functional SE images. We conclude that ultrafast MR imaging shows promise as a convenient dynamic evaluation of craniovertebral junctional disorders. (author).

  14. A cephalometric method to diagnosis the craniovertebral junction abnormalities in osteogenesis imperfecta patients

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    Ríos-Rodenas, Mercedes; Gutiérrez-Díez, María-Pilar; Feijóo, Gonzalo; Mourelle, Maria-Rosa; Garcilazo, Mario; Ortega-Aranegui, Ricardo

    2015-01-01

    Osteogenesis imperfecta (OI) is a hereditary bone fragility disorder that in most patients is caused by mutations affecting collagen type I. Their typical oral and craneofacial characteristics (Dentinogenesis imperfecta type I and class III malocclusion), involve the dentist in the multidisciplinary team that treat these patients. It is usual to perform lateral skull radiographs for the orthodontic diagnosis. In addition, this radiograph is useful to analyse the junctional area between skull base and spine, that could be damaged in OI. Pathology in the craneovertebral junction (CVJ) is a serious complication of OI with a prevalence ranging from rare to 37%. To diagnosis early skull base anomalies in these patients, previously the neurological symptoms have been appear, we make a simple cephalometric analysis of the CVJ. This method has four measurements and one angle. Once we calculate the values of the OI patient, we compare the result with the mean and the standard deviations of an age-appropriate average in healthy controls. If the patient has a result more than 2,5 SDs above the age-appropriate average in healthy controls, we should to refer the patient to his/her pediatrician or neurologist. These doctors have to consider acquiring another diagnostic images to be used to determine cranial base measurements with more reliability. Thereby, dentists who treat these patients, must be aware of the normal radiological anatomy of the cervical spine on the lateral cephalogram. Key words:Osteogenesis imperfecta, craniovertebral junction, cephalometric. PMID:25810828

  15. Endoscopic endonasal transclival transodontoid approach for ventral decompression of the craniovertebral junction: operative technique and nuances.

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    Liu, James K; Patel, Jimmy; Goldstein, Ira M; Eloy, Jean Anderson

    2015-04-01

    The transoral approach is considered the gold-standard surgical route for performing anterior odontoidectomy and ventral decompression of the craniovertebral junction for pathological conditions that result in symptomatic cervicomedullary compression, including basilar invagination, rheumatoid pannus, platybasia with retroflexed odontoid processes, and neoplasms. Extended modifications to increase the operative corridor and exposure include the transmaxillary, extended "open-door" maxillotomy, transpalatal, and transmandibular approaches. With the advent of extended endoscopic endonasal skull base techniques, there has been increased interest in the last decade in the endoscopic endonasal transclival transodontoid approach to the craniovertebral junction. The endonasal route represents an attractive minimally invasive surgical alternative, especially in cases of irreducible basilar invagination in which the pathology is situated well above the palatine line. Angled endoscopes and instrumentation can also be used for lower-lying pathology. By avoiding the oral cavity and subsequently using a transoral retractor, the endonasal route has the advantages of avoiding complications related to tongue swelling, tracheal swelling, prolonged intubation, velopharyngeal insufficiency, dysphagia, and dysphonia. Postoperative recovery is quicker, and hospital stays are shorter. In this report, the authors describe and illustrate their method of purely endoscopic endonasal transclival odonotoidectomy for anterior decompression of the craniovertebral junction and describe various operative pearls and nuances of the technique for avoiding complications.

  16. A complex craniovertebral junction malformation in a patient with late onset glycogenosis 2

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    Mariasofia Cotelli

    2014-01-01

    Full Text Available Glycogenosis II (GSDII is an autosomal recessive lysosomal storage disorder resulting from deficiency of acid alpha-glucosidase and subsequent lysosomal accumulation of glycogen in skeletal, cardiac and smooth muscles. The late-onset form is characterized by wide variability of the phenotypical spectrum. Clinical findings may include muscle weakness, respiratory insufficiency, vascular abnormalities, low bone mineral density and higher risk of developing osteoporosis. Craniovertebral junction (CVJ malformations have never been described so far. We here report on a GSDII 43-year-old woman who harbored the mutations IVS1-13T>G and c.2237G>A in the acid alpha-glucosidase gene. She recurrently suffered from headache, neck pain and dizziness. Brain MRI and CT scan showed the presence of a very rare complex CVJ malformation composed of basilar invagination, basiocciput hypoplasia, partial C1 assimilation, C1 posterior arch aplasia and C1 lateral mass hypoplasia and offset. Although we cannot rule out their coincidental occurrence, the rarity of multiple CVJ malformations in the general population as well as the well-known GSDII multisystem involvement should suggest to study the CVJ in the diagnostic process of GSDII patients in order to assess the CVJ malformation frequency in GSDII population and verify a possible relationship between these two conditions.

  17. Transoral approach to the craniovertebral junction Acesso transoral para a junção craniocervical

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    José Alberto Landeiro

    2007-12-01

    Full Text Available The transoral approach provides a safe exposure to lesions in the midline and the ventral side of the craniovertebral junction. The advantages of the transoral approach are 1 the impinging bony pathology and granulation tissue are accessible only via the ventral route; 2 the head is placed in the extended position, thus decreasing the angulation of the brainstem during the surgery; and 3 surgery is done through the avascular median pharyngeal raphe and clivus. We analyzed the clinical effects of odontoidectomy after treating 38 patients with basilar invagination. The anterior transoral operation to treat irreducible ventral compression in patients with basilar invagination was performed in 38 patients. The patients’ ages ranged from 34 to 67 years. Fourteen patients had associated Chiari malformation and eight had previously undergone posterior decompressive surgery. The main indication for surgery was significant neurological deterioration. Symptoms and signs included neck pain, myelopathy, lower cranial nerve dysfunction, nystagmus and gait disturbance. Extended exposure was performed in 24 patients. The surgery was beneficial to the majority of patients. There was one death within 10 days of surgery, due to pulmonary embolism. Postoperative complications included two cases of pneumonia, three cases of oronasal fistula with regurgitation and one cerebrospinal fluid leak. In patients with marked ventral compression, the transoral approach provides direct access to the anterior face of the craniovertebral junction and effective means for odontoidectomy.O acesso transoral é uma via direta e segura às lesões situadas na linha média e na face anterior da junção craniocervical. As vantagens do acesso transoral são as seguintes:1 a compressão óssea e o tecido de granulação localizam-se anteriormente e são accessíveis pela via anterior; 2 a cabeça do paciente é colocada em extensão, diminuindo a angulação do tronco cerebral durante

  18. Correction of immune disorders in patients with malignant tumors at level of craniovertebral junction and upper cervical spine

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    Bazhanov S.P.

    2013-06-01

    Full Text Available Objective: To study the cellular and humoral immunity in patients with malignant tumors of the upper cervical spine. Material and methods: The study included 22 patients with malignant tumors of the craniovertebral junction and upper cervical spine. To assess the function of the immune system the methods of population and subpopulation immuno-phenotyping of peripheral blood lymphocytes have been applied. Cytokine parameters and functional status (cytotoxic activity of NK-cells have been studied using immunofermental methods. The indices have been presented in absolute and relative terms. All the patients have been subjected to the adjuvant therapy. Results: Correction of cellular immunity has led to significant increase in CD3 + (T-lymphocytes and CD3 + CD8 + (T-killers. Cytokine levels in the groups studied in the dynamics have not been significantly altered. The changes of cytotoxic (functional activity of NK-cells in the first group after the combined treatment have been considered to be higher than before the treatment. Cytotoxic index of (functional activity of NK-cells in the second group under the study after the combined treatment has been determined to be lower than before the treatment. Conclusion: It has been found out that the application of complex treatment accompanied by immunotropic therapy may positively influence the immune status.

  19. Syringomyelia associated with arachnoid septum at the craniovertebral junction, contradicting the currently prevailing theory of syringomyelia formation.

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    Chang, Han Soo; Tsuchiya, Tsukasa; Fujisawa, Naoaki; Oya, Soichi; Matsui, Toru

    2012-01-01

    Despite a number of various hypotheses in the literature, the pathophysiology of syringomyelia is still not well understood. In this article, we report two cases of cervical syringomyelia not associated with Chiari I malformation. Both cases had a septum-like structure in the subarachnoid space on the dorsal side of the cord at the craniovertebral junction. Cardiac-gated phase-contrast cine-mode magnetic resonance imaging (MRI) demonstrated decreased cerebrospinal fluid (CSF) flow on the dorsal side of the spinal cord. Surgical excision of this septum, restoring the CSF flow, resulted in a prompt reduction of the syrinx size in both cases. Findings in these cases contradict the currently prevailing hypothesis of syrinx formation that postulate that the piston-like movement of the cerebellar tonsils enhance the pulsatile CSF flow in the spinal subarachnoid space, driving the CSF into the syrinx through the perivascular space of Virchow and Robin. The authors propose that a mechanism based on the decreased pulsatile CSF flow in the spinal subarachnoid space will be more suitable as a hypothesis in studying the pathophyisiology of syringomyelia. These cases also provide an important lesson in managing the patients with syringomyelia not associated with Chiari I malformation.

  20. Craniovertebral junction malformation in Northeastern Brazil: the myth of the Dutch colonization Malformação da junção craniovertebral no Nordeste do Brasil: o mito da colonização Holandesa

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    Claudio Henrique Fernandes Vidal

    2013-06-01

    Full Text Available The high prevalence of craniovertebral junction malformation in Northeastern Brazil is historically associated with brachycephalic biotype (flat head, also common in this region. It has been postulated that this trait was introduced to this region by the Dutch during the colonial period in Brazil's history. Based on the confrontation of this paradigm against some historical facts, the authors concluded that the brachycephalic phenotype was inherited from prehistoric ancestors (Amerindians who were already living in this region when white European men arrived.A alta prevalência de malformação da junção craniovertebral no Nordeste do Brasil é historicamente associada ao biótipo braquicefálico (cabeça chata, também comum nessa região. Postula-se que essa característica tenha sido introduzida na região pelos holandeses durante o período colonial da história do Brasil. Com base na confrontação desse paradigma com alguns fatos históricos, os autores concluem que o fenótipo braquicefálico foi herdado de ancestrais pré-históricos (ameríndios que já habitavam a região no momento da chegada do homem branco europeu.

  1. Hydrodynamic and longitudinal impedance analysis of cerebrospinal fluid dynamics at the craniovertebral junction in type I Chiari malformation.

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    Bryn A Martin

    Full Text Available Elevated or reduced velocity of cerebrospinal fluid (CSF at the craniovertebral junction (CVJ has been associated with type I Chiari malformation (CMI. Thus, quantification of hydrodynamic parameters that describe the CSF dynamics could help assess disease severity and surgical outcome. In this study, we describe the methodology to quantify CSF hydrodynamic parameters near the CVJ and upper cervical spine utilizing subject-specific computational fluid dynamics (CFD simulations based on in vivo MRI measurements of flow and geometry. Hydrodynamic parameters were computed for a healthy subject and two CMI patients both pre- and post-decompression surgery to determine the differences between cases. For the first time, we present the methods to quantify longitudinal impedance (LI to CSF motion, a subject-specific hydrodynamic parameter that may have value to help quantify the CSF flow blockage severity in CMI. In addition, the following hydrodynamic parameters were quantified for each case: maximum velocity in systole and diastole, Reynolds and Womersley number, and peak pressure drop during the CSF cardiac flow cycle. The following geometric parameters were quantified: cross-sectional area and hydraulic diameter of the spinal subarachnoid space (SAS. The mean values of the geometric parameters increased post-surgically for the CMI models, but remained smaller than the healthy volunteer. All hydrodynamic parameters, except pressure drop, decreased post-surgically for the CMI patients, but remained greater than in the healthy case. Peak pressure drop alterations were mixed. To our knowledge this study represents the first subject-specific CFD simulation of CMI decompression surgery and quantification of LI in the CSF space. Further study in a larger patient and control group is needed to determine if the presented geometric and/or hydrodynamic parameters are helpful for surgical planning.

  2. Optimal measurement for "posterolateral protrusion" of the vertebral artery at the craniovertebral junction using computed tomography angiography

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    Junichi Ohya

    2014-01-01

    Full Text Available Purpose: Among extraosseous abnormalities of the vertebral artery (VA at the craniovertebral junction (CVJ, available evidence regarding "posterolateral protrusion," the VA running distant from the groove over the superior surface of the posterior arch of the atlas, is limited. The purpose of this study was to determine the optimal measurement to indicate posterolateral protrusion of the VA. Materials and Methods: Computed tomography angiography (CTA images of 40 consecutive patients with cervical disease were reviewed. Ultimately, 66 arteries were included in this study. Five parameters predicted to indicate posterolateral protrusion of the VA were defined (A-E and measured by two surgeons twice over a 2-week interval. Intraclass correlation coefficients (ICC were used to examine intra-observer reproducibility and inter-observer reliability. Receiver operating characteristic (ROC curve analysis was performed to determine the most optimal parameter to predict posterolateral protrusion of the VA. Results: Excellent inter-observer reliability and intra-observer reproducibility were obtained for all parameters (ICC = 0.87-0.99. Among them, parameter A, defined as the maximal length from the outer surface of the VA to the outer surface of the posterior arch of the atlas, was most accurately described posterolateral protrusion of the VA. The optimal cut-off value of parameter A obtained with ROC curves was 8.3 mm (sensitivity 97.5%, specificity 100%. Conclusions: The measurement in this study can quantitatively evaluate the posterolateral protrusion of the VA. Before posterior surgery at the CVJ, pre-operative CTA can help surgeons detect anomalous VA and reduce the risk of intra-operative VA injury.

  3. Craniovertebral junction 360°: A combined microscopic and endoscopic anatomical study

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    Sukhdeep Singh Jhawar

    2016-01-01

    Conclusion: With advances in endoscopic and microscopic techniques, access to lesions and bony anomalies around CVJ is becoming easier and straightforward. A combination of microscopic and endoscopic techniques is more useful to understand this anatomy and may aid in the development of future combined approaches.

  4. Calcification of the Alar Ligament Mimics Fracture of the Craniovertebral Junction (CVJ): An Incidental Finding from Computerised Tomography of the Cervical Spine Following Trauma

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    Che Mohamed, Siti Kamariah; Abd. Aziz, Azian

    2009-01-01

    When performing a radiological assessment for a trauma case with associated head injury, a fragment of dense tissue detected near the craniovertebral junction would rapidly be assessed as a fractured bone fragment. However, if further imaging and evaluation of the cervical spine with computerised tomography (CT) did not demonstrate an obvious fracture, then the possibility of ligament calcification would be considered. We present a case involving a previously healthy 44-yearold man who was admitted following a severe head injury from a road traffic accident. CT scans of the head showed multiple intracranial haemorrhages, while scans of the cervical spine revealed a small, well-defined, ovoid calcification in the right alar ligament. This was initially thought to be a fracture fragment. Although such calcification is uncommon, accident and emergency physicians and radiologists may find this useful as a differential diagnosis in patients presenting with neck pain or traumatic head injury. PMID:22135515

  5. Unique paradoxical atlantoaxial dislocation with C1-C2 facet diastases and isolated ligamentous injury to the craniovertebral junction without neurological deficits: A case report

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    Aniruddha Thekkatte Jagannatha

    2013-01-01

    Full Text Available Study design: Retrospective review of the case file. Objective: The primary objective was to report this rare case and discuss the mechanism of dislocation and technique of manual closed reduction of C1-C2 vertebrae in such scenarios. Summary of background data: Posterior atlantoaxial dislocation (AAD is extremely rare and a few cases have been reported in English literature. This young man sustained a high speed car accident and survived an extreme hyperextension injury to the craniovertebral junction (CVJ without any neurological deficits. On evaluation for neck pain he was noted with a dislocated odontoid lying in front of Atlas. There was C1-C2 facet diastases. No bony injury was noted at CVJ. Transverse axial ligament (TAL was intact. He underwent a successful awake reduction of the dislocation. The joint had to be manually distracted, realigned, and released under the guidance of fluoroscopy. This was followed by single stage C1-C2 Goel′s fusion with awake prone positioning. This patient was able to go back to work at the end of 3 months (GOS 5. Conclusions: This condition is extremely rare, can be carefully reduced manually under adequate neuromonitoring, and requires C1-C2 fusion in the same sitting.

  6. Successful Removal of a Metastatic Gastrointestinal Stromal Tumor in the Craniovertebral Junction using an Occipital Artery to Posterior Inferior Cerebellar Artery Bypass

    Directory of Open Access Journals (Sweden)

    Yukitomo Ishi

    2014-05-01

    Full Text Available Gastrointestinal stromal tumors (GISTs are rare mesenchymal neoplasms arising from the gastrointestinal tract. The authors present a case of the successful removal of a metastatic GIST in the craniovertebral junction, using an occipital artery to posterior inferior cerebellar artery (OA-PICA bypass. The patient is a 54-year-old male who underwent his first surgery for a small-bowel tumor at the age of 45 and was diagnosed with GIST. Nine years after his primary diagnosis, the patient suffered from severe neck pain. MRI demonstrated a large demarcated mass adjacent to the right atlas. The right vertebral artery (VA, completely engulfed by the tumor, showed a narrowing and ended in the PICA. Poor collateral blood supply in the right PICA territory was presumed. To prevent ischemic complications, an OA-PICA bypass was performed prior to the tumor resection. After the OA-PICA bypass, the tumor associated with the right VA was successfully removed, and the patient was discharged without any neurological deficits.

  7. A revolution in preventing fatal craniovertebral junction injuries: lessons learned from the Head and Neck Support device in professional auto racing.

    Science.gov (United States)

    Kaul, Anand; Abbas, Ahmed; Smith, Gabriel; Manjila, Sunil; Pace, Jonathan; Steinmetz, Michael

    2016-12-01

    Fatal craniovertebral junction (CVJ) injuries were the most common cause of death in high-speed motor sports prior to 2001. Following the death of a mutual friend and race car driver, Patrick Jacquemart (1946-1981), biomechanical engineer Dr. Robert Hubbard, along with race car driver and brother-in-law Jim Downing, developed the concept for the Head and Neck Support (HANS) device to prevent flexion-distraction injuries during high-velocity impact. Biomechanical testing showed that neck shear and loading forces experienced during collisions were 3 times the required amount for a catastrophic injury. Crash sled testing with and without the HANS device elucidated reductions in neck tension, neck compression, head acceleration, and chest acceleration experienced by dummies during high-energy crashes. Simultaneously, motor sports accidents such as Dale Earnhardt Sr.'s fatal crash in 2001 galvanized public opinion in favor of serious safety reform. Analysis of Earnhardt's accident demonstrated that his car's velocity parallel to the barrier was more than 150 miles per hour (mph), with deceleration upon impact of roughly 43 mph in a total of 0.08 seconds. After careful review, several major racing series such as the National Association for Stock Car Auto Racing (NASCAR) and Championship Auto Racing Team (CART) made major changes to ensure the safety of drivers at the turn of the 21st century. Since the rule requiring the HANS device in professional auto racing series was put in place, there has not been a single reported case of a fatal CVJ injury.

  8. Three-dimensional endoscope-assisted surgical approach to the foramen magnum and craniovertebral junction: minimizing bone resection with the aid of the endoscope.

    Science.gov (United States)

    Anichini, Giulio; Evins, Alexander I; Boeris, Davide; Stieg, Philip E; Bernardo, Antonio

    2014-12-01

    To evaluate objectively the anatomic areas of the cranial base exposed by a three-dimensional (3D) endoscope-assisted far lateral approach. A series of far lateral approaches with only condyle resection, with only jugular tubercle resection, with both partial condyle and total jugular tubercle resection, and without occipital condyle and jugular tubercle resection were performed on 10 cadaveric heads (20 sides). To assess properly the exposure of major anatomic and neurovascular structures, the intradural anatomy of the exposed craniocervical junction was divided into 8 compartments, including 3 superior cranial compartments, 3 inferior cranial compartments, and 2 spinal compartments. The anteromedial compartments toward the midline were difficult to explore using the microscope and required the aid of the endoscope. The 3D endoscope provided general circumferential visualization of the anatomic structures, even without resection of the jugular tubercle, and afforded good visualization of the more lateral compartments. Safe and optimal surgical corridors for insertion of the endoscope were also identified. Use of a 3D endoscope allows for minimal resection of the condyle and jugular tubercle, better visualization of the surgical compartments toward the midline, and better in-depth surgical exploration of each intradural compartment. However, the 3D probe is still too large and restricts surgical maneuverability. Copyright © 2014 Elsevier Inc. All rights reserved.

  9. Universality of conductance in mesoscopic junctions and chiral anomaly

    Energy Technology Data Exchange (ETDEWEB)

    Oxman, Luis E.; Mucciolo, Eduardo R. [Universidadade Catolica do Rio de Janeiro, Rio de Janeiro (Brazil)

    2001-03-01

    We show that the electrical conductance of one-dimensional, finite systems with chiral symmetry is not renormalized at low temperatures and depends solely on the characteristics of the electron gas at the leads. This chiral symmetry is related to the invariance under phase transformations that distinguish between left- and right-moving electrons. Alternatively to previous works in the literature, we employ a fermionic path integral formalism which does not rely on bosonization. The fundamental role played by the reservoirs and the finite size of the junctions is put into evidence. [Spanish] En este articulo mostramos que en sistemas unidimensionales finitos con simetria quiral, la conductancia electrica no se renormaliza a bajas temperaturas, y depende solamente de las caracteristicas del gas de electrones en los reservatorios. Esta simetria quiral esta relacionada a la invariancia ante transformadores de fase que distinguen entre modos derechos e izquierdos. Empleamos un formalismo de integral funcional sobre fermiones, el cual constituye una alternativa al metodo de bosonizacion utilizado previamente en la literatura. Tambien ponemos en evidencia el papel fundamental desempenado por los reservatorios y el tamano finito de la muestra.

  10. Parity Anomaly and Spin Transmutation in Quantum Spin Hall Josephson Junctions

    Science.gov (United States)

    Peng, Yang; Vinkler-Aviv, Yuval; Brouwer, Piet W.; Glazman, Leonid I.; von Oppen, Felix

    2016-12-01

    We study the Josephson effect in a quantum spin Hall system coupled to a localized magnetic impurity. As a consequence of the fermion parity anomaly, the spin of the combined system of impurity and spin-Hall edge alternates between half-integer and integer values when the superconducting phase difference across the junction advances by 2 π . This leads to characteristic differences in the splittings of the spin multiplets by exchange coupling and single-ion anisotropy at phase differences, for which time-reversal symmetry is preserved. We discuss the resulting 8 π -periodic (or Z4) fractional Josephson effect in the context of recent experiments.

  11. Developmental anomalies at craniocervical junction with special emphasis on computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Miyasaka, Kazuo; Isu, Toyohiko; Abe, Satoru; Takei, Hidetoshi; Kaneda, Kiyoshi (Hokkaido Univ., Sapporo (Japan). School of Medicine)

    1983-04-01

    The diagnostic value of CT was evaluated in 44 cases of developmental anomaly at the craniocervical junction, particularly for atlantoaxial dislocation (AAD), basilar invagination and Chiari malformation. CT visualized the mutual relationships among the occiput, atlas and axis for AAD (23 cases) and the soft tisse of the posterior surface of the dens (10/23 cases). In basilar invagination (20 cases), the elevated foraminal margin on the axial plane and the identified dens on the foraminal plane led to suspicion of this disease. It was essential, however, to validate elevation of the foraminal margin and developmental anomalies of the occipital bone by reconstruction of coronary and saggital plane images, or by plain tomography. In Chiari malformation (23 cases), high resolution CT (13) visualized tonsillar ptosis in all of the cases. Thus, CT was highly effective as a screening test for Chiari malformation. CTM was satisfactory in identification of anatomical structures such as ptotic medulla oblongata-4th ventricle and most valuable in the diagnosis of associated syringomyelia.

  12. Expanding the spectrum of congenital anomalies of the diencephalic-mesencephalic junction

    Energy Technology Data Exchange (ETDEWEB)

    Severino, Mariasavina; Tortora, Domenico; Rossi, Andrea [Istituto Giannina Gaslini, Neuroradiology Unit, Genova (Italy); Pistorio, Angela [Istituto Giannina Gaslini, Epidemiology and Biostatistics Unit, Genoa (Italy); Ramenghi, Luca Antonio [Istituto Giannina Gaslini, Neonatal Intensive Care Unit, Genoa (Italy); Napoli, Flavia [Istituto Giannina Gaslini, Endocrinology Unit, Genoa (Italy); Mancardi, Maria Margherita [Istituto Giannina Gaslini, Neuropsychiatry Unit, Genoa (Italy); Striano, Pasquale [Istituto Giannina Gaslini, Paediatric Neurology and Muscular Diseases Unit, Genoa (Italy); Capra, Valeria [Istituto Giannina Gaslini, Genetic Unit, Genoa (Italy)

    2016-01-15

    We aimed to describe the clinico-radiological findings of patients with disorders of diencephalic-mesencephalic junction (DMJ) formation and midbrain anteroposterior patterning. We reviewed the DMJ anatomy of 445 patients with brain malformations. Associated supra/infratentorial abnormalities and clinical findings were noted. Craniocaudal and anteroposterior diameters of midbrain, pons, medulla, vermis, and transverse cerebellar diameter were compared with age-matched controls. Post hoc tests were corrected according to Bonferroni (p{sub B}). Two patterns of DMJ anomaly were identified in 12 patients (7 females, mean age 41 months). Type A was characterized by hypothalamic-mesencephalic fusion on axial plane, with possible midbrain ventral cleft (7 patients). Anteroposterior (p{sub B} =.006) and craniocaudal (p{sub B} =.027) diameters of the pons, craniocaudal diameter of the vermis (p{sub B} =.015), and transverse cerebellar diameter (p{sub B} =.011) were smaller than the controls. Corticospinal tract, basal ganglia, and commissural anomalies were also associated. Clinical findings included spastic-dystonic tetraparesis, hypothalamic dysfunction, epilepsy, and severe developmental delay. Type B was characterized by incomplete thalamic-mesencephalic cleavage on sagittal plane, with parenchymal bands connecting the interthalamic adhesion with the midbrain (five patients). Anteroposterior diameters of midbrain (p{sub B} =.002), pons (p{sub B} =.0004), and medulla (p{sub B} =.002) as well as the vermian anteroposterior (p{sub B} =.040) and craniocaudal diameters (p{sub B} =.014) were smaller than the controls. These patients were less neurologically impaired, most presenting mild developmental delay. The spectrum of DMJ patterning defects is wide and may be associated with several brain malformations. Infratentorial brain structures should be carefully evaluated to better define the type of associated midbrain-hindbrain anomalies. (orig.)

  13. Anomalies.

    Science.gov (United States)

    Online-Offline, 1999

    1999-01-01

    This theme issue on anomalies includes Web sites, CD-ROMs and software, videos, books, and additional resources for elementary and junior high school students. Pertinent activities are suggested, and sidebars discuss UFOs, animal anomalies, and anomalies from nature; and resources covering unexplained phenonmenas like crop circles, Easter Island,…

  14. Cerebrovascular disturbances in children with Arnold-Kiary anomaly I

    Directory of Open Access Journals (Sweden)

    Kozlitina T.N.

    2012-03-01

    Full Text Available Data of diagnostics of cerebrovascular disorders in craniovertebral passage due to Arnold — Kiary anomaly I have been considered. Clinical picture of the disease in different age groups has been represented. Condition of extra- and intracranial part of vertebral arteries and venous plexuses of the cervical part of vertebral column and craniovertebral passage, pathological asymmetry of the blood flow have been estimated. Efficacy of conservative and surgical treatment has been compared.

  15. Nonoperative management of craniovertebral junction and cutaneous tuberculosis

    Directory of Open Access Journals (Sweden)

    Shaun Previn Appaduray

    2015-01-01

    Conclusion: CVJ TB may be treated solely with anti-TB therapy and immobilization to good effect if there is no gross instability or neurological deficit. Similarly, cutaneous TB responds well to standard anti- TB therapy. Our experience suggests that co-existing tuberculous lesions in the CVJ and skin can be simultaneously managed with standard therapy without significant alterations to treatment regimes or prognosis.

  16. C1-2 vertebral anomalies in 22q11.2 microdeletion syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Konen, Osnat; Armstrong, Derek; Padfield, Nancy; Blaser, Susan [Hospital for Sick Children, Diagnostic Imaging, Toronto (Canada); Clarke, Howard [Hospital for Sick Children, Plastic Surgery, Toronto (Canada); Weksberg, Rosanna [Hospital for Sick Children, Clinical and Metabolic Genetics, Toronto (Canada)

    2008-07-15

    Chromosome 22q11.2 microdeletion syndrome (22q11DS) is characterized by cleft palate, cardiac anomalies, characteristic facies, high prevalence of skeletal anomalies and learning disability. To evaluate the prevalence of craniovertebral junction anomalies in children with 22q11DS and compare these findings to those in nonsyndromic children with velopharyngeal insufficiency (VPI). Sequential CT scans performed for presurgical carotid assessment in 76 children (45 children positive for chromosome 22q11.2 deletion and 31 negative for the deletion) with VPI were retrospectively evaluated for assessment of C1-2 anomalies. C1-2 vertebral anomalies, specifically midline C1 defects, uptilted or upswept posterior elements of C2 and fusions of C2-3, were nearly universal in our cohort of 22q11DS patients with VPI. They were strikingly absent in the majority of non-22q11DS patients with VPI. C1-2 vertebral anomalies, particularly those listed above, are important radiographic markers for 22q11DS. (orig.)

  17. Clinical value of extension-flexion MRI in evaluating the indication of internal fixation for patients of craniovertebral junction malformation%前屈-后伸位MRI对判断颅脊交界区畸形内固定指征的临床价值

    Institute of Scientific and Technical Information of China (English)

    陈赞; 孙永华; 吴浩; 王兴文; 菅凤增

    2011-01-01

    目的:分析前屈-后伸位MRI对诊断Arnold-Chiari畸形可能合并寰枢椎脱位的作用,以及指导治疗的临床意义.方法:回顾分析40例Arnold-Chiari畸形患者的前屈-后伸位MRI影像学资料,测量寰齿间距,通过前屈位和后伸位颈椎椎管狭窄程度分级,判断颅脊交界区稳定性.单纯Arnold-Chiari畸形患者采用枕大孔减压和枕大池扩大成形术,存在寰枢椎脱位者兼行枕颈内固定融合术.结果:经前屈-后伸位MRI检查,证实有12例患者存在颅颈失稳,于枕大孔减压的同时行枕颈内固定融合术.手术后第3天颈椎影像学检查,40例中10例脊髓空洞病灶明显缩小;12例兼行枕颈内固定融合术者颅颈复位满意,脊髓压迫解除;手术后3个月随访,脊髓空洞病灶明显缩小(17例),颅脊交界区骨痂形成、骨融合效果良好、颅颈复位无丢失(12例),日本矫形外科评分13.08±1.40,与手术前评分(11.08±1.61)比较,差异有统计学意义(t=5.928,P=0.000).结论:前屈-后伸位MRI对判断颅脊交界区稳定性、选择适宜的手术方式具有重要意义.%Objective To analyse the value of cervical extension - flexion magnetic resonance imaging (EFMRI) in the evaluation of possible atlantoaxial dislocation (AAD) associated with Arnold-Chiari malformation.Methods Reviewed the image studies of 40 Arnold-Chiari malformation patients, including 19 females and 21 males.The cervical EFMRI was evaluated, atlantodental interval (ADI) was measured and spinal canal narrowing grade was evaluated to judge the instability of craniovertebral junction (CVJ).The diagnostic criteria of instability of CVJ was that ADI increased more than 2 mm between flexion and the neutral or extention position in dynamic MRI, or the spinal canal stenosis grade increased more than one grade between flexion and the neutral or extention position in dynamic MRI.Foramen magnum decompression and cisterna magna plasty were performed for the Arnold - Chiari

  18. Ureteropelvic junction obstruction in children: two variants of the same congenital anomaly?

    Directory of Open Access Journals (Sweden)

    Braga Luis H.P.

    2003-01-01

    Full Text Available OBJECTIVE: To compare the characteristics of prenatally and postnatally diagnosed ureteropelvic junction obstruction (UPJO in children. PATIENTS AND METHODS: We reviewed the records of 74 children who underwent pyeloplasty or nephrectomy for UPJO between 1995 and 2000. The patients were divided into 2 groups: prenatally and postnatally diagnosed UPJO. In each group, we compared age at surgery, gender, affected side, anteroposterior diameter (APD of the renal pelvis, surgical findings, and renal function as determined by creatinine clearance. RESULTS: Of the 74 children, 44 (59.4% had a prenatal diagnosis of UPJO and 30 (40.6% had a postnatal diagnosis despite the fact that all had had a fetal ultrasonography. Median age at the time of surgery was 6.3 years (4 months to 16 years for children with postnatal UPJO and 3.6 months (1 month to 4 years for the prenatal group. Forty-three percent of the children in the postnatal group and 25% in the prenatal group were females. Clinical manifestations in children with postnatal UPJO included abdominal pain in 13 (43% patients, pyelonephritis in 7 (23%, urinary tract infection in 5 (16.6%, and occasional findings upon ultrasound in 5 (16.6%. Excretory urography suggested obstruction in most children. The surgical findings included ureteral kinks due to adhesions in 93.3% of postnatally diagnosed UPJO cases and in 27.3% of prenatal cases (p < 0.01. A reduction in mean creatinine clearance of hydronephrotic kidneys was observed for both groups when compared to reference values for the respective ages, but this difference was not statistically significant. CONCLUSIONS: Postnatally diagnosed UPJO may be considered, at least in part, an entity different from prenatally detected obstruction due to its peculiar characteristics, i.e., postnatal UPJO more frequently affects females, manifests later in life with urinary infection or abdominal pain, and is frequently associated with ureteral kinking.

  19. True oblique axis fracture associated with congenital anomalies of the upper cervical spine: Case report of an unusual fracture pattern

    Science.gov (United States)

    Robles, Luis A.

    2017-01-01

    Background: Acute traumatic axis fractures are common cervical spine injuries often caused by road accidents or falls. They are usually classified into three different types, namely, odontoid fractures, Hangman's fractures, and miscellaneous fractures. Congenital malformations of the craniovertebral junction (CVJ), although typically asymptomatic, may result in neural compression or instability, especially following trauma. Here, the authors present an unusual oblique axis fracture occurring in conjunction with several malformations of the upper cervical spine. Case Description: Following a motor vehicle accident, a 25-year-old female's radiographic studies showed an oblique axis fracture involving both the anterior and posterior elements along with an anterior and posterior Klippel–Feil syndrome (KFS) anomaly. Following treatment in a halo vest, the patient maintained alignment, and ultimately the fracture was fused. Conclusions: True oblique fractures of the axis are rare, as in the case presented, and may occasionally occur in conjunction with KFS of the upper cervical spine. PMID:28217386

  20. Suboccipital craniectomy with opening of the fourth ventricle and duraplasty: study of 192 cases of craniovertebral malformations

    Directory of Open Access Journals (Sweden)

    Jose Alberto Goncalves da Silva

    2013-09-01

    Full Text Available The prime objective in the surgical treatment of basilar impression (BI, Chiari malformation (CM, and/or syringomyelia (SM is based on restoration of the normal cerebrospinal fluid (CSF dynamics at the craniovertebral junction and creation of a large artificial cisterna magna, avoiding the caudal migration of the hindbrain. It is observed that a large craniectomy might facilitate an upward migration of the posterior fossa structures. There are many surgical techniques to decompress the posterior fossa; however, a gold standard approach remains unclear. The authors present the results of 192 cases of BI, CM, and SM treated between 1975 and 2008 and whose surgical treatment was characterized by a large craniectomy without tonsillectomy with the patient in the sitting position, large opening of the fourth ventricle, and duraplasty.

  1. [Cerebrovenous orthostatic reactivity in pathology of the craniovertebral junction (Chiari malformation)].

    Science.gov (United States)

    Shakhnovich, V A; Mitrofanova, E V; Shimanskiy, V N; Konovalov, N A; Shkarubo, A N

    2015-01-01

    Мальформация Киари характеризуется вклинением миндалин мозжечка в большое затылочное отверстие, что приводит к нарушению циркуляции ликвора через краниовертебральный переход. Адекватным методом для выявления этих нарушений являются ортостатические нагрузки, которые приводят к перемещению ликвора через краниовертебральный переход. Возникающие при этом изменения внутричерепного давления оказывают влияние на церебровенозную ортостатическую реактивность (ЦВОР), которая оценивается неинвазивно при мальформации Киари. Материал и методы. Исследование проведено у 35 больных с мальформацией Киари (Киари I — 26 больных, Киари II — 9) в возрасте от 4 до 58 лет. Среди обследованных больных у 4 была выявлена гидроцефалия, у 6 — сирингомиелия. Методом транскраниальной допплерографии регистрировали венозный кровоток в прямом синусе мозга при изменении положения тела на ортостоле от +90° до –30°. Результаты. У больных с мальформацией Киари ЦВОР существенно отличается от нормы (более чем в 90% случаев) как ее увеличением (иногда в 5—6 раз по сравнению с верхней границей нормы — значительная гиперреактивность), так и полным отсутствием каких-либо изменений при ортостатической нагрузке (ареактивность). У больных c мальформацией Киари до хирургического лечения ЦВОР чаще всего характеризуется ареактивностью, а также умеренной или значительной гиперреактивностью. После хирургического лечения (декомпрессия большого затылочного отверстия) у больных с мальформацией Киари отмечается существенная нормализация краниовертебральных объемных соотношений, а ЦВОР чаще всего характеризуется нормореактивностью (63%), реже — умеренной гиперреактивностью. Скорость венозного кровотока в прямом синусе мозга при мальформации Киари до операции бывает повышена, а после хирургического лечения нормализуется. Выводы. Выявлена высокая частота нарушений ЦВОР (более 90% случаев) у больных с мальформацией Киари. После хирургического лечения этих больных больше чем в половине наблюдений (63%) отмечается полная нормализация ЦВОР.

  2. Endoscope-assisted microsurgical transoral approach to the anterior craniovertebral junction compressive pathologies

    National Research Council Canada - National Science Library

    Visocchi, Massimiliano; Doglietto, Francesco; Della Pepa, Giuseppe Maria; Esposito, Giuseppe; La Rocca, Giuseppe; Di Rocco, Concezio; Maira, Giulio; Fernandez, Eduardo

    2011-01-01

    At the present time, an update to the classical microsurgical transoral decompression is strongly provided by the most recent literature dealing with the introduction of the endoscopy in spine surgery...

  3. Continuous positive airway pressure alters cranial blood flow and cerebrospinal fluid dynamics at the craniovertebral junction

    Directory of Open Access Journals (Sweden)

    Theresia I. Yiallourou

    2015-09-01

    Conclusion: Application of CPAP via a full-fitted mask at 15 cm H2O was found to have a significant effect on intracranial venous outflow and spinal CSF flow at the C2 vertebral level in healthy adult-age awake volunteers. CPAP can be used to non-invasively provoke changes in intracranial and CSF flow dynamics.

  4. Canine Model of Choledochopancreatic Junction Anomaly%异常胰胆管连接动物模型的建立

    Institute of Scientific and Technical Information of China (English)

    吕维富; 许萍; 巫北海; 段恒春; 余昌中; 董家鸿; 张建超

    1995-01-01

    为制作异常胰胆管连接(APBDU)最佳动物模型,笔者用23只犬分两组分别行胆总管→背胰管(13只)和背胰管→胆总管(10只)端侧吻合术.术前,术后5,10,15,30,50,80,120天和处死时(90~270天)动态检测血清淀粉酶、磷脂酶A2活性和甘胆酸含量,结合胰胆管测压、造影和病理切片等的观察表明:①本模型的胰胆管连接形态十分接近人类APBDU的解剖特点.②术后各犬无永久性吻合口狭窄且能保证持续性胆汁和胰液混流.⑧能诱发人类APBDU所合并的多种胰胆系病变.结论:本模型为符合人类APBDU的解剖和病理生理特点,能反映其病理演变规律的最佳模型.%In order to inquire into the best animal model of choledochopancreatic junction anomaly (CPJA), an end to side anastomosis of common bile duct to dorsal pancrea tic duct was performed in 13 dogs and the same anasomo. sis vise versa in 10 dogs. After operation, the phospholipase A_2 activity, amylase activity and level of conjugated glycine bile acid in serum were measured on the 5th, 10th, 15th, 30th, 50th, 80th and 120th day respectively , and cholangiopancreatography, manometry and pathological examination of biliary and pancreatic ducts were performed on 90th to 270th day. the results showed that: 1. this model was similar to human CPJA on anatomy; 2. there was no permanent narrowing at the anastomsis; 3. a free reflux of bile and pancreatic juice was permitted; 4. this model could induce many kinds of pancreatobiliary diseases associated with CPJA including cholecystitis, cholangitis, choledochol dilatation, pancreatitis and so on. This animal model is quite similar to the human CPJA in anatomy and physiology as well as in the pathologic pattern.

  5. Vertebral artery variations and osseous anomaly at the C1-2 level diagnosed by 3D CT angiography in normal subjects

    Energy Technology Data Exchange (ETDEWEB)

    Wakao, Norimitsu; Kamiya, Mitsuhiro [Aichi Medical University, Department of Spine Center, Aichi (Japan); Aichi Medical University, Department of Orthopedic Surgery, Nagakute, Aichi (Japan); Takeuchi, Mikinobu; Hirasawa, Atsuhiko; Kawanami, Katsuhisa; Takayasu, Masakazu [Aichi Medical University, Department of Spine Center, Aichi (Japan); Nishimura, Manabu [Aichi Medical University, Department of Radiology, Nagakute, Aichi (Japan); Riew, K.D. [Washington University, Department of Orthopedic Surgery, St. Louis, MO (United States); Imagama, Shiro [Nagoya University, Department of Orthopedic Surgery, Nagoya, Aichi (Japan); Sato, Keiji [Aichi Medical University, Department of Orthopedic Surgery, Nagakute, Aichi (Japan)

    2014-10-15

    The craniovertebral junction is anatomically complicated. Representative vertebral artery (VA) variations include the persistent first intersegmental artery (FIA), fenestration of the VA above and below C1 (FEN), posterior inferior cerebellar artery (PICA) from C1/2, and high-riding VA (HRVA). The ponticulus posticus (PP) is a well-known osseous anomaly at C1. Although those anomalies are frequent in patients with cervical deformity, the prevalence of these in subjects with normal cervical spines is still unknown. The aim of this study is to investigate the variations and prevalence of vascular and osseous anomalies based on three-dimensional computed tomographic (3D CT) angiography in patients without any cervical diseases, such as rheumatoid arthritis, Klippel-Feil syndrome, or Down syndrome. Eligible subjects were patients who underwent 3D CT angiography by the Department of Otorhinolaryngology and Internal Medicine from January 2009 to October 2013 in our institution. The authors defined a HRVA as a C2 pedicle with a maximum diameter of 4 mm or less. Among 480 subjects with a mean age of 63.1 years, 387 patients were eligible. One hundred and eighteen subjects were female, and 269 were male. HRVA was observed in 10.1 % of patients (39 out of 387 cases), FIA in 1.8 % (7 cases), FEN in 1.3 % (5 cases), and PICA in 1.3 % (5 cases). PP was observed in 6.2 % of patients (24 cases). According to past reports, many VA anomalies could be attributed to congenital or acquired conditions (e.g., rheumatoid arthritis). However, VA anomalies appear to exist even in patients without any such cervical diseases. (orig.)

  6. Demonstrated Anomalous Pancreaticobiliary Ductal Junction

    OpenAIRE

    Koçkar, Cem; ?ENOL, Altu?; BA?TÜRK, Abdulkadir; AYDIN, Bünyamin; Cüre, Erkan

    2015-01-01

    Anomalies of the pancreaticobiliary junction are rare. Clinically anomalies of the pancreaticobiliary junction are uncommonly symptomatic but may present themselves with associated conditions ranging from benign acute abdominal pain to carcinomas. A 52 years old man was admitted to gastroenterology service with complaints of fever, nausea, vomiting and recurrent epigastric pain. He was diagnosed with biliary pancreatitis. Endoscopic retrograde cholangiopancreato-graphy was performed. Papilla ...

  7. Urinary System anomalies at birth

    Directory of Open Access Journals (Sweden)

    Sharada B. Menasinkai

    2015-06-01

    Full Text Available Background: Congenital anomalies of urinary system are common and are found in 3-4% of population, and lethal urinary anomalies account for 10% of termination of pregnancy. Methods: A study was done to know the incidence of congenital anomalies at birth for the period of 4 months from May 99 - Sept 99 at Cheluvamba hospital attached to Mysore medical college. Congenital anomalies in the still births, live births and aborted fetuses >20 weeks were studied along with the case history and ultrasound reports. Aborted fetuses and still born babies were collected for autopsy after the consent of parents. These babies were fixed in 10% formalin and autopsy was done after fixing, and anomalies were noted. Results: Total births during study period were 3000. There were 61 babies with congenital anomalies and 6 babies had anomalies of urinary system. Among the urinary system anomalies 1 baby had bilateral renal agenesis, 1 baby had unilateral renal agenesis with anophthalmia (Fraser syndrome, 2 babies had Multicystic dysplastic kidney disease (MCDK and 1 live baby had hydronephrosis due to obstruction at pelvi ureteric junction, and 1 live female baby had polycystic kidneys. Conclusion: Incidence of urinary system anomalies in the present study was 2 per 1000 births. U/S detection of urinary anomalies varies with period of gestation, amniotic fluid volume and visualisation of urinary bladder. Autopsy helps to detect renal agenesis. [Int J Res Med Sci 2015; 3(3.000: 743-748

  8. Development and Congenital Anomalies of the Pancreas

    Directory of Open Access Journals (Sweden)

    Hiroyuki Tadokoro

    2011-01-01

    Full Text Available Understanding how the pancreas develops is essential to understand the pathogenesis of congenital pancreatic anomalies. Recent studies have shown the advantages of investigating the development of frogs, mice, and chickens for understanding early embryonic development of the pancreas and congenital anomalies, such as choledochal cysts, anomalous pancreaticobiliary junction, annular pancreas, and pancreas divisum. These anomalies arise from failure of complete rotation and fusion during embryogenesis. There are many theories in the etiology of congenital anomalies of the pancreas. We review pancreas development in humans and other vertebrates. In addition, we attempt to clarify how developmental failure is related to congenital pancreatic anomalies.

  9. Development and Congenital Anomalies of the Pancreas

    OpenAIRE

    Hiroyuki Tadokoro; Masaru Takase; Bunsei Nobukawa

    2011-01-01

    Understanding how the pancreas develops is essential to understand the pathogenesis of congenital pancreatic anomalies. Recent studies have shown the advantages of investigating the development of frogs, mice, and chickens for understanding early embryonic development of the pancreas and congenital anomalies, such as choledochal cysts, anomalous pancreaticobiliary junction, annular pancreas, and pancreas divisum. These anomalies arise from failure of complete rotation and fusion during embryo...

  10. Craniovertebral malformation complex in a child with Weismann-Netter-Stuhl syndrome.

    Science.gov (United States)

    Al Kaissi, Ali; Ben Chehida, Farid; Gharbi, Hassan; Jinziri, Mourad; Safi, Hatem; Ben Ghachem, Maher; Grill, Franz; Varga, Franz; Klaushofer, Klaus

    2006-01-01

    Bowing of the legs is usually thrown into the basket of vitamin D deficiency rickets; therefore, a significant number of affected children can be misdiagnosed and improperly managed. This case illustrates how the careful clinical and radiological assessment of such a case can lead to the adequate understanding of its etiology. We report a sporadic case of a 2-year-old male child who presented with radiological features that were compatible with Weismann-Netter-Stuhl syndrome. In addition, we observed craniovertebral malformation complex. He was of normal intelligence. To our knowledge, the combination of Weismann-Netter-Stuhl syndrome and presence of a hypoplastic occipitalized atlas and further C2-C3 fusion has not been reported before. The diagnosis of Weismann-Netter-Stuhl is discussed. Classically, Weismann-Netter-Stuhl syndrome is characterized by short stature, mental retardation (in some individuals), dural calcification, and anterior bowing of the tibiae. However, we believe that careful clinical and radiological examinations can reveal more striking data which might positively reflect on the whole process of management. We postulate that the congenital limitations in neck movements in our patient developed because of the marked fusion of the hypoplastic and occipitalized atlas and simultaneous C2-C3 fusion. Therefore, if this form of malformation is disregarded, there may be involvement of the atlantoaxial structure, and this can possibly lead to serious neurological and even life-threatening complications. The use of CT scanning for the detection of such abnormalities can be remarkably important.

  11. Anomaly holography

    Energy Technology Data Exchange (ETDEWEB)

    Gripaios, Ben [Rudolf Peierls Centre for Theoretical Physics, University of Oxford, 1 Keble Rd., Oxford OX1 3NP (United Kingdom); Merton College, Oxford OX1 4JD (United Kingdom)], E-mail: b.gripaios1@physics.ox.ac.uk; West, Stephen M. [Rudolf Peierls Centre for Theoretical Physics, University of Oxford, 1 Keble Rd., Oxford OX1 3NP (United Kingdom)], E-mail: s.west1@physics.ox.ac.uk

    2008-01-21

    We consider, in the effective field theory context, anomalies of gauge field theories on a slice of a five-dimensional, anti-de Sitter geometry and their four-dimensional, holographic duals. A consistent effective field theory description can always be found, notwithstanding the presence of the anomalies and without modifying the degrees of freedom of the theory. If anomalies do not vanish, the d=4 theory contains additional pseudoscalar states, which are either present in the low-energy theory as physical, light states, or are eaten by (would-be massless) gauge bosons. We show that the pseudoscalars ensure that global anomalies of the four-dimensional dual satisfy the 't Hooft matching condition and comment on the relevance for warped models of electroweak symmetry breaking.

  12. Weyl Anomaly and Initial Singularity Crossing

    CERN Document Server

    Awad, Adel

    2015-01-01

    We consider the role of quantum effects, mainly, Weyl anomaly in modifying FLRW model singular behavior at early times. Weyl anomaly corrections to FLRW models have been considered in the past, here we reconsider this model and show the following: The singularity of this model is weak according to Tipler and Krolak, therefore, the spacetime might admit a geodesic extension. Weyl anomaly corrections changes the nature of the initial singularity from a big bang singularity to a sudden singularity. The two branches of solutions consistent with the semiclassical treatment form a disconnected manifold. Joining these two parts at the singularity provides us with a $C^1$ extension to nonspacelike geodesics and leaves the spacetime geodesically complete. Using Gauss-Codazzi equations one can derive generalized junction conditions for this higher-derivative gravity. The extended spacetime obeys Friedmann and Raychaudhuri equations and the junction conditions. The junction does not generate Dirac delta functions in mat...

  13. Gap Junctions

    Science.gov (United States)

    Nielsen, Morten Schak; Axelsen, Lene Nygaard; Sorgen, Paul L.; Verma, Vandana; Delmar, Mario; Holstein-Rathlou, Niels-Henrik

    2013-01-01

    Gap junctions are essential to the function of multicellular animals, which require a high degree of coordination between cells. In vertebrates, gap junctions comprise connexins and currently 21 connexins are known in humans. The functions of gap junctions are highly diverse and include exchange of metabolites and electrical signals between cells, as well as functions, which are apparently unrelated to intercellular communication. Given the diversity of gap junction physiology, regulation of gap junction activity is complex. The structure of the various connexins is known to some extent; and structural rearrangements and intramolecular interactions are important for regulation of channel function. Intercellular coupling is further regulated by the number and activity of channels present in gap junctional plaques. The number of connexins in cell-cell channels is regulated by controlling transcription, translation, trafficking, and degradation; and all of these processes are under strict control. Once in the membrane, channel activity is determined by the conductive properties of the connexin involved, which can be regulated by voltage and chemical gating, as well as a large number of posttranslational modifications. The aim of the present article is to review our current knowledge on the structure, regulation, function, and pharmacology of gap junctions. This will be supported by examples of how different connexins and their regulation act in concert to achieve appropriate physiological control, and how disturbances of connexin function can lead to disease. © 2012 American Physiological Society. Compr Physiol 2:1981-2035, 2012. PMID:23723031

  14. Gap junctions.

    Science.gov (United States)

    Nielsen, Morten Schak; Axelsen, Lene Nygaard; Sorgen, Paul L; Verma, Vandana; Delmar, Mario; Holstein-Rathlou, Niels-Henrik

    2012-07-01

    Gap junctions are essential to the function of multicellular animals, which require a high degree of coordination between cells. In vertebrates, gap junctions comprise connexins and currently 21 connexins are known in humans. The functions of gap junctions are highly diverse and include exchange of metabolites and electrical signals between cells, as well as functions, which are apparently unrelated to intercellular communication. Given the diversity of gap junction physiology, regulation of gap junction activity is complex. The structure of the various connexins is known to some extent; and structural rearrangements and intramolecular interactions are important for regulation of channel function. Intercellular coupling is further regulated by the number and activity of channels present in gap junctional plaques. The number of connexins in cell-cell channels is regulated by controlling transcription, translation, trafficking, and degradation; and all of these processes are under strict control. Once in the membrane, channel activity is determined by the conductive properties of the connexin involved, which can be regulated by voltage and chemical gating, as well as a large number of posttranslational modifications. The aim of the present article is to review our current knowledge on the structure, regulation, function, and pharmacology of gap junctions. This will be supported by examples of how different connexins and their regulation act in concert to achieve appropriate physiological control, and how disturbances of connexin function can lead to disease. © 2012 American Physiological Society. Compr Physiol 2:1853-1872, 2012.

  15. Cisto de colédoco em adulto: anomalia da junção do colédoco com o ducto pancreático submetido à ressecção do cisto e à derivação biliar e pancreática Common bile duct cyst in adult: anomaly of the common bile duct-pancreatic junction submitted to excision of the cyst and a biliary and pancreatic deviation

    Directory of Open Access Journals (Sweden)

    Manlio Basilio Speranzini

    2008-04-01

    Full Text Available Common bile duct cysts are rare congenital anomalies which have been diagnosed only in twenty per cent of adults. The etiology is uncertain, but many patients have an anomalous pancreatobiliary junction anatomy. We present a case of a young man with a type I Alonso-Lej/ Todani common bile duct cyst and an anomalous common bile duct-pancreatic junction anatomy. Because the common bile duct did not have a segment of normal caliber, to avoid compromising with the pancreatic channel after the excision of the cyst, we performed a Roux-en-Y anastomosis by anastomosing the biliary duct to the proximal excluded jejunal loop and the common duct-pancreatic junction to the same more distally loop.

  16. Clinical management of cranio-vertebral instability after whiplash, when guidelines should be adapted: a case report.

    Science.gov (United States)

    Rebbeck, Trudy; Liebert, Ann

    2014-12-01

    Cranio-vertebral instability (CVI) due to loss of bony or ligamentous integrity is one of the sequelae that may result after a whiplash mechanism injury. Due to the lack of specificity of diagnostic tests, this condition is often missed and the default classification of whiplash associated disorder (WAD) is assigned. This case report describes a 14-year-old boy who was initially classified with WAD II after a rugby injury. He was initially advised to return to usual activity, a treatment recommended in clinical guidelines for WAD. Due to an adverse response to this course of action, his primary carer, a musculoskeletal physiotherapist, continued with facilitating secondary referrals that ultimately led to a specialist physiotherapist. The patient was subsequently found to have CVI arising from a loss of bony integrity due to spina bifida atlanto, a congenital defect in the atlas. Treatment thus was immobilization and stabilization, a treatment usually recommended against in WAD guidelines. The patient recovered and within 8 weeks had returned to school and non-contact sports. This case study, therefore, presents a scenario where current clinical guidelines for whiplash could not be followed, and where pursuing clinical reasoning led to accurate diagnosis as well as safe and tailored management. The case also highlights the integrated roles that primary and specialist health professionals should play in the clinical pathway of care after WAD. As a result, an expanded diagnostic algorithm and pathway of care for WAD are proposed.

  17. Anomaly Structure of Supergravity and Anomaly Cancellation

    CERN Document Server

    Butter, Daniel

    2009-01-01

    We display the full anomaly structure of supergravity, including new D-term contributions to the conformal anomaly. This expression has the super-Weyl and chiral U(1)_K transformation properties that are required for implementation of the Green-Schwarz mechanism for anomaly cancellation. We outline the procedure for full anomaly cancellation. Our results have implications for effective supergravity theories from the weakly coupled heterotic string theory.

  18. Measurement of craniovertebral angle by the Modified Head Posture Spinal Curvature Instrument: A reliability and validity study.

    Science.gov (United States)

    Subbarayalu, Arun Vijay

    2016-01-01

    The Modified Head Posture Spinal Curvature Instrument (MHPSCI) is an extension of the Head Posture Spinal Curvature Instrument. Two specific modifications were made in the original design by adding a third arm projecting horizontally from the protractor to objectively fix the pivot exactly over the C7 vertebra and the addition of a spirit-level to properly align the instrument. In order to demonstrate reliability and validity, this study was conducted using patients with postural neck pain (N = 65) and healthy subjects (N = 20). All the subjects were working at a selected Information Technology Industry in India and had been recruited using a criterion-based sampling approach. The craniovertebral (CV) angle of each subject was evaluated by two raters consecutively. The measurements were taken by using both MHPSCI and the standard photographic method in a standardized sitting posture for the purpose of establishing criterion-validity of the instrument. The results of this study indicate a good inter-rater reliability (ICC = 0.76; CI = 0.65-0.84) as well as intra-rater reliability (ICC = 0.87; CI = 0.82-0.91) between three successive CV angle measurements (with 2 minutes interval between each measurement) through MHPSCI. While keeping the digital photographic measurement as a standard, this study established that the MHPSCI is a valid tool for measuring the CV angle as shown by non-significant difference (p > 0.01) and high correlation between the two methods (r = 0.79-0.84). This study demonstrates that the MHPSCI is a reliable and valid instrument for measuring CV angle in subjects with or without postural neck pain.

  19. Chiral anomalies and differential geometry

    Energy Technology Data Exchange (ETDEWEB)

    Zumino, B.

    1983-10-01

    Some properties of chiral anomalies are described from a geometric point of view. Topics include chiral anomalies and differential forms, transformation properties of the anomalies, identification and use of the anomalies, and normalization of the anomalies. 22 references. (WHK)

  20. Complexo de malformação craniovertebral em uma criança com síndrome de Weismann-Netter-Stuhl Craniovertebral malformation complex in a child with Weismann-Netter-Stuhl syndrome

    Directory of Open Access Journals (Sweden)

    Ali Al Kaissi

    2006-06-01

    Full Text Available OBJETIVO: O arqueamento das pernas geralmente é atribuído ao raquitismo causado pela carência de vitamina D; portanto, várias crianças afetadas acabam sendo classificadas erroneamente e tratadas inadequadamente. Este caso ilustra como uma avaliação clínica e radiológica cuidadosa pode levar à elucidação de sua causa. DESCRIÇÃO: Relatamos um caso esporádico de um menino de 2 anos de idade que apresentou achados radiológicos compatíveis com síndrome de Weismann-Netter-Stuhl. Além disso, observamos o complexo de malformação craniovertebral. O paciente possuía inteligência normal. Até onde sabemos, a combinação de síndrome de Weismann-Netter-Stuhl e occipitalização do atlas hipoplásico e posterior fusão das vértebras C2 e C3 nunca foi relatada antes. Descrevemos o diagnóstico da síndrome de Weismann-Netter-Stuhl. As características clássicas da síndrome de Weismann-Netter-Stuhl são baixa estatura, retardamento mental (em alguns indivíduos, calcificação da dura-máter e arqueamento anterior da tíbia. Todavia, acreditamos que um exame clínico e radiológico cuidadoso possa revelar dados mais contundentes que poderiam influenciar positivamente o processo de tratamento. COMENTÁRIOS: Presumimos que as limitações congênitas dos movimentos do pescoço em nosso paciente surgiram por causa da fusão acentuada do osso occipital ao atlas hipoplásico e da fusão simultânea da segunda e terceira vértebras. Portanto, se desconsiderarmos esse tipo de malformação, a estrutura atlanto-axial poderá ser comprometida, o que poderá causar complicações neurológicas sérias e até mesmo fatais. A tomografia tem um papel crucial na detecção dessas anormalidades.OBJECTIVE: Bowing of the legs is usually thrown into the basket of vitamin D deficiency rickets; therefore, a significant number of affected children can be misdiagnosed and improperly managed. This case illustrates how the careful clinical and radiological

  1. Tracheobronchial Branching Anomalies

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Min Ji; Kim, Young Tong; Jou, Sung Shick [Soonchunhyang University, Cheonan Hospital, Cheonan (Korea, Republic of); Park, A Young [Soonchunhyang University College of Medicine, Asan (Korea, Republic of)

    2010-04-15

    There are various congenital anomalies with respect to the number, length, diameter, and location of tracheobronchial branching patterns. The tracheobronchial anomalies are classified into two groups. The first one, anomalies of division, includes tracheal bronchus, cardiac bronchus, tracheal diverticulum, pulmonary isomerism, and minor variations. The second one, dysmorphic lung, includes lung agenesis-hypoplasia complex and lobar agenesis-aplasia complex

  2. Molecular electronic junction transport

    DEFF Research Database (Denmark)

    Solomon, Gemma C.; Herrmann, Carmen; Ratner, Mark

    2012-01-01

    Whenasinglemolecule,oracollectionofmolecules,isplacedbetween two electrodes and voltage is applied, one has a molecular transport junction. We discuss such junctions, their properties, their description, and some of their applications. The discussion is qualitative rather than quantitative, and f...

  3. Competing Orders and Anomalies

    Science.gov (United States)

    Moon, Eun-Gook

    2016-08-01

    A conservation law is one of the most fundamental properties in nature, but a certain class of conservation “laws” could be spoiled by intrinsic quantum mechanical effects, so-called quantum anomalies. Profound properties of the anomalies have deepened our understanding in quantum many body systems. Here, we investigate quantum anomaly effects in quantum phase transitions between competing orders and striking consequences of their presence. We explicitly calculate topological nature of anomalies of non-linear sigma models (NLSMs) with the Wess-Zumino-Witten (WZW) terms. The non-perturbative nature is directly related with the ’t Hooft anomaly matching condition: anomalies are conserved in renormalization group flow. By applying the matching condition, we show massless excitations are enforced by the anomalies in a whole phase diagram in sharp contrast to the case of the Landau-Ginzburg-Wilson theory which only has massive excitations in symmetric phases. Furthermore, we find non-perturbative criteria to characterize quantum phase transitions between competing orders. For example, in 4D, we show the two competing order parameter theories, CP(1) and the NLSM with WZW, describe different universality class. Physical realizations and experimental implication of the anomalies are also discussed.

  4. Anomaly-induced baryogenesis

    CERN Document Server

    Kobakhidze, A

    2004-01-01

    We propose a new mechanism for dynamical generation of the observed baryon asymmetry within the minimal Standard model extended by massive Majorana neutrinos and non-vanishing electroweak Chern-Simons term. We show that electroweak Chern-Simons number is produced in the expanding universe due to the conformal anomaly and subsequently converted into baryon number through the triangle anomaly.

  5. Competing Orders and Anomalies.

    Science.gov (United States)

    Moon, Eun-Gook

    2016-08-08

    A conservation law is one of the most fundamental properties in nature, but a certain class of conservation "laws" could be spoiled by intrinsic quantum mechanical effects, so-called quantum anomalies. Profound properties of the anomalies have deepened our understanding in quantum many body systems. Here, we investigate quantum anomaly effects in quantum phase transitions between competing orders and striking consequences of their presence. We explicitly calculate topological nature of anomalies of non-linear sigma models (NLSMs) with the Wess-Zumino-Witten (WZW) terms. The non-perturbative nature is directly related with the 't Hooft anomaly matching condition: anomalies are conserved in renormalization group flow. By applying the matching condition, we show massless excitations are enforced by the anomalies in a whole phase diagram in sharp contrast to the case of the Landau-Ginzburg-Wilson theory which only has massive excitations in symmetric phases. Furthermore, we find non-perturbative criteria to characterize quantum phase transitions between competing orders. For example, in 4D, we show the two competing order parameter theories, CP(1) and the NLSM with WZW, describe different universality class. Physical realizations and experimental implication of the anomalies are also discussed.

  6. A Correlation between Renal Anomalies and Vesicoureteral Reflux

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Seung Soo; Kim, Young Tong; Kim, Il Young; Shin, Hyeong Cheol [Dept. of Radiology, Cheonan Hospital, Soonchunhyang University College of Medicine, Cheonan (Korea, Republic of)

    2011-12-15

    To investigate the frequency of vesicoureteral reflux (VUR) in children with renal anomalies a evaluate the correlation between renal anomalies and VUR. Eighty-one children (1 day-8 years) with renal anomalies underwent voiding cystourethrogram between 2006 and 2009 were reviewed. This study included ureteropelvic junction stenosis (n = 32), ureteropelvic duplication (n = 20), multicystic dysplastic kidney (n = 12), fusion anomaly (n = 11), renal agenesis (n = 3), unilateral renal hypoplasia (n = 2), and ectopic kidney (n = 1). The frequency, grade, and location of VUR were evaluated. The grade of VUR according to age and anomaly type was statistically analyzed, and the patients with VUR were followed. The VUR was present in 14 (17.3%); ipsilateral VUR was present in 8 (57.1%), bilateral VUR in 4 (28.6%), and contralateral VUR in 2 (14.2%). VUR was detected in 9 patients under the age of one. There was no statistical correlation between VUR grade and either age or anomaly type of the nine patients showed continuous VUR on up. The frequency of VUR in children with renal anomalies was 17.3%. VUR was most frequently detected in children under the age of one, and VUR grade was not related to age and anomaly type.

  7. Anomalies on orbifolds

    Energy Technology Data Exchange (ETDEWEB)

    Arkani-Hamed, Nima; Cohen, Andrew G.; Georgi, Howard

    2001-03-16

    We discuss the form of the chiral anomaly on an S1/Z2 orbifold with chiral boundary conditions. We find that the 4-divergence of the higher-dimensional current evaluated at a given point in the extra dimension is proportional to the probability of finding the chiral zero mode there. Nevertheless the anomaly, appropriately defined as the five dimensional divergence of the current, lives entirely on the orbifold fixed planes and is independent of the shape of the zero mode. Therefore long distance four dimensional anomaly cancellation ensures the consistency of the higher dimensional orbifold theory.

  8. Theoretically Optimal Distributed Anomaly Detection

    Data.gov (United States)

    National Aeronautics and Space Administration — A novel general framework for distributed anomaly detection with theoretical performance guarantees is proposed. Our algorithmic approach combines existing anomaly...

  9. Anomaly Detection in Sequences

    Data.gov (United States)

    National Aeronautics and Space Administration — We present a set of novel algorithms which we call sequenceMiner, that detect and characterize anomalies in large sets of high-dimensional symbol sequences that...

  10. Neutrino anomalies without oscillations

    Indian Academy of Sciences (India)

    Sandip Pakvasa

    2000-01-01

    I review explanations for the three neutrino anomalies (solar, atmospheric and LSND) which go beyond the `conventional' neutrino oscillations induced by mass-mixing. Several of these require non-zero neutrino masses as well.

  11. Scattering anomaly in optics

    CERN Document Server

    Silveirinha, Mario G

    2016-01-01

    In time-reversal invariant electronic systems the scattering matrix is anti-symmetric. This property enables an effect, designated here as "scattering anomaly", such that the electron transport does not suffer from back reflections, independent of the specific geometry of the propagation path or the presence of time-reversal invariant defects. In contrast, for a generic time-reversal invariant photonic system the scattering matrix is symmetric and there is no similar anomaly. Here, it is theoretically proven that despite these fundamental differences there is a wide class of photonic platforms - in some cases formed only by time-reversal invariant media - in which the scattering anomaly can occur. It is shown that an optical system invariant under the action of the composition of the time-reversal, parity and duality operators is characterized by an anti-symmetric scattering matrix. Specific examples of photonic platforms wherein the scattering anomaly occurs are given, and it is demonstrated with full wave n...

  12. The Pioneer Anomaly

    CERN Document Server

    de Diego, Jose A

    2008-01-01

    Analysis of the radio-metric data from Pioneer 10 and 11 spacecrafts has indicated the presence of an unmodeled acceleration starting at 20 AU, which has become known as the Pioneer anomaly. The nature of this acceleration is uncertain. In this paper we give a description of the effect and review some relevant mechanisms proposed to explain the observed anomaly. We also discuss on some future projects to investigate this phenomenon.

  13. DREDed Anomaly Mediation

    CERN Document Server

    Boyda, E; Pierce, A T; Boyda, Ed; Murayama, Hitoshi; Pierce, Aaron

    2002-01-01

    We offer a guide to dimensional reduction (DRED) in theories with anomaly mediated supersymmetry breaking. Evanescent operators proportional to epsilon arise in the bare Lagrangian when it is reduced from d=4 to d= (4-2 epsilon) dimensions. In the course of a detailed diagrammatic calculation, we show that inclusion of these operators is crucial. The evanescent operators conspire to drive the supersymmetry-breaking parameters along anomaly-mediation trajectories across heavy particle thresholds, guaranteeing the ultraviolet insensitivity.

  14. Anomalies and gravity

    CERN Document Server

    Mielke, E W

    2006-01-01

    Anomalies in Yang-Mills type gauge theories of gravity are reviewed. Particular attention is paid to the relation between the Dirac spin, the axial current j_5 and the non-covariant gauge spin C. Using diagrammatic techniques, we show that only generalizations of the U(1)- Pontrjagin four--form F^ F= dC arise in the chiral anomaly, even when coupled to gravity. Implications for Ashtekar's canonical approach to quantum gravity are discussed.

  15. SADM potentiometer anomaly investigations

    Science.gov (United States)

    Wood, Brian; Mussett, David; Cattaldo, Olivier; Rohr, Thomas

    2005-07-01

    During the last 3 years Contraves Space have been developing a Low Power (1-2kW) Solar Array Drive Mechanism (SADM) aimed at small series production. The mechanism was subjected to two test programmes in order to qualify the SADM to acceptable levels. During the two test programmes, anomalies were experienced with the Potentiometers provided by Eurofarad SA and joint investigations were undertaken to resolve why these anomalies had occurred. This paper deals with the lessons learnt from the failure investigation on the two Eurofarad (rotary) Potentiometer anomaly. The Rotary Potentiometers that were used were fully redundant; using two back to back mounted "plastic tracks". It is a pancake configuration mounted directly to the shaft of the Slip Ring Assembly at the extreme in-board end of the SADM. It has no internal bearings. The anomaly initially manifested itself as a loss of performance in terms of linearity, which was first detected during Thermal Vacuum testing. A subsequent anomaly manifested itself by the complete failure of the redundant potentiometer again during thermal vacuum testing. This paper will follow and detail the chain of events following this anomaly and identifies corrective measures to be applied to the potentiometer design and assembly process.

  16. Magnetic tunnel junctions (MTJs)

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    We review the giant tunnel magnetoresistance (TMR) in ferromagnetic-insulator-ferromagnetic junctions discovered in recent years, which is the magnetoresistance (MR) associated with the spin-dependent tunneling between two ferromagnetic metal films separated by an insulating thin tunnel barrier. The theoretical and experimental results including junction conductance, magnetoresistance and their temperature and bias dependences are described.

  17. Stacked Josephson Junctions

    DEFF Research Database (Denmark)

    Madsen, Søren Find; Pedersen, Niels Falsig; Christiansen, Peter Leth

    2010-01-01

    Long Josephson junctions have for some time been considered as a source of THz radiation. Solitons moving coherently in the junctions is a possible source for this radiation. Analytical computations of the bunched state and bunching-inducing methods are reviewed. Experiments showing THz radiation...

  18. The effect of feedback respiratory exercise on muscle activity, craniovertebral angle, and neck disability index of the neck flexors of patients with forward head posture.

    Science.gov (United States)

    Kang, Jeong-Il; Jeong, Dae-Keun; Choi, Hyun

    2016-09-01

    [Purpose] This study aimed to simultaneously investigate the activities of the sternocleidomastoid muscle and scalenus anterior muscle, which are agonists of neck and breathing accessory muscles, by implementing breathing exercises. [Subjects and Methods] Thirteen subjects were selected for the experimental group, which performed feedback respiratory exercises with McKenzie exercises, and 12 subjects were selected for the control group, which performed McKenzie exercises alone. The intervention program was performed for 30 minutes a session, once a day, four times a week, and for 2 weeks before conducting the experiment. Before intervention, muscle activity was measured using surface electromyogram, and the neck disability index was evaluated. [Results] There were meaningful differences in activities of the sternocleidomastoid muscle and the scalenus anterior muscle, craniovertebral angle, and neck disability index within both the experimental group and control group after intervention. There also were meaningful differences in sternocleidomastoid muscle and neck disability index changes between groups. [Conclusion] Neck flexors as accessory respiratory muscle can affect inefficient respiratory imbalance of forward head posture patients. Multimodal intervention method should be studied continually and not be exposed to upper chest breathing patterns by preventing such phenomenon.

  19. Anomalies without Massless Particles

    CERN Document Server

    Gurlanik, Z

    1994-01-01

    Baryon and lepton number in the standard model are violated by anomalies, even though the fermions are massive. This problem is studied in the context of a two dimensional model. In a uniform background field, fermion production arise from non-adiabatic behavior that compensates for the absence of massless modes. On the other hand, for localized instanton-like configurations, there is an adiabatic limit. In this case, the anomaly is produced by bound states which travel across the mass gap. The sphaleron corresponds to a bound state at the halfway point.

  20. Classical Trace Anomaly

    OpenAIRE

    Farhoudi, M.

    1995-01-01

    We seek an analogy of the mathematical form of the alternative form of Einstein's field equations for Lovelock's field equations. We find that the price for this analogy is to accept the existence of the trace anomaly of the energy-momentum tensor even in classical treatments. As an example, we take this analogy to any generic second order Lagrangian and exactly derive the trace anomaly relation suggested by Duff. This indicates that an intrinsic reason for the existence of such a relation sh...

  1. Congenital laryngeal anomalies,

    Directory of Open Access Journals (Sweden)

    Michael J. Rutter

    2014-12-01

    Full Text Available Introduction: It is essential for clinicians to understand issues relevant to the airway management of infants and to be cognizant of the fact that infants with congenital laryngeal anomalies are at particular risk for an unstable airway. Objectives: To familiarize clinicians with issues relevant to the airway management of infants and to present a succinct description of the diagnosis and management of an array of congenital laryngeal anomalies. Methods: Revision article, in which the main aspects concerning airway management of infants will be analyzed. Conclusions: It is critical for clinicians to understand issues relevant to the airway management of infants.

  2. The reactor antineutrino anomalies

    Energy Technology Data Exchange (ETDEWEB)

    Haser, Julia; Buck, Christian; Lindner, Manfred [Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany)

    2016-07-01

    Major discoveries were made in the past few years in the field of neutrino flavour oscillation. Nuclear reactors produce a clean and intense flux of electron antineutrinos and are thus an essential neutrino source for the determination of oscillation parameters. Most currently the reactor antineutrino experiments Double Chooz, Daya Bay and RENO have accomplished to measure θ{sub 13}, the smallest of the three-flavour mixing angles. In the course of these experiments two anomalies emerged: (1) the reanalysis of the reactor predictions revealed a deficit in experimentally observed antineutrino flux, known as the ''reactor antineutrino anomaly''. (2) The high precision of the latest generation of neutrino experiments resolved a spectral shape distortion relative to the expected energy spectra. Both puzzles are yet to be solved and triggered new experimental as well as theoretical studies, with the search for light sterile neutrinos as most popular explanation for the flux anomaly. This talk outlines the two reactor antineutrino anomalies. Discussing possible explanations for their occurrence, recent and upcoming efforts to solve the reactor puzzles are highlighted.

  3. Bolivian Bouguer Anomaly Grid

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A 1 kilometer Bouguer anomaly grid for the country of Bolivia.Number of columns is 550 and number of rows is 900. The order of the data is from the lower left to the...

  4. Minnesota Bouguer Anomaly Grid

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A 1.5 kilometer Bouguer anomaly grid for the state of Minnesota. Number of columns is 404 and number of rows is 463. The order of the data is from the lower left to...

  5. Equivalent Josephson junctions

    Science.gov (United States)

    Boyadjiev, T. L.; Semerdjieva, E. G.; Shukrinov, Yu. M.

    2008-01-01

    The magnetic field dependences of critical current are numerically constructed for a long Josephson junction with a shunt-or resistor-type microscopic inhomogeneities and compared to the critical curve of a junction with exponentially varying width. The numerical results show that it is adequate to replace the distributed inhomogeneity of a long Josephson junction by an inhomogeneity localized at one of its ends, which has certain technological advantages. It is also shown that the critical curves of junctions with exponentially varying width and inhomogeneities localized at the ends are unaffected by the mixed fluxon-antifluxon distributions of the magnetic flow. This fact may explain the improvement of the spectra of microwave radiation noted in the literature.

  6. Astrometric solar system anomalies

    Energy Technology Data Exchange (ETDEWEB)

    Nieto, Michael Martin [Los Alamos National Laboratory; Anderson, John D [PROPULSION LABORATORY

    2009-01-01

    There are at least four unexplained anomalies connected with astrometric data. perhaps the most disturbing is the fact that when a spacecraft on a flyby trajectory approaches the Earth within 2000 km or less, it often experiences a change in total orbital energy per unit mass. next, a secular change in the astronomical unit AU is definitely a concern. It is increasing by about 15 cm yr{sup -1}. The other two anomalies are perhaps less disturbing because of known sources of nongravitational acceleration. The first is an apparent slowing of the two Pioneer spacecraft as they exit the solar system in opposite directions. Some astronomers and physicists are convinced this effect is of concern, but many others are convinced it is produced by a nearly identical thermal emission from both spacecraft, in a direction away from the Sun, thereby producing acceleration toward the Sun. The fourth anomaly is a measured increase in the eccentricity of the Moon's orbit. Here again, an increase is expected from tidal friction in both the Earth and Moon. However, there is a reported unexplained increase that is significant at the three-sigma level. It is produent to suspect that all four anomalies have mundane explanations, or that one or more anomalies are a result of systematic error. Yet they might eventually be explained by new physics. For example, a slightly modified theory of gravitation is not ruled out, perhaps analogous to Einstein's 1916 explanation for the excess precession of Mercury's perihelion.

  7. The Pioneer Anomaly

    Directory of Open Access Journals (Sweden)

    Viktor T. Toth

    2010-09-01

    Full Text Available Radio-metric Doppler tracking data received from the Pioneer 10 and 11 spacecraft from heliocentric distances of 20-70 AU has consistently indicated the presence of a small, anomalous, blue-shifted frequency drift uniformly changing with a rate of ~6 × 10–9 Hz/s. Ultimately, the drift was interpreted as a constant sunward deceleration of each particular spacecraft at the level of aP = (8.74 ± 1.33 × 10–10 m/s2. This apparent violation of the Newton's gravitational inverse square law has become known as the Pioneer anomaly; the nature of this anomaly remains unexplained. In this review, we summarize the current knowledge of the physical properties of the anomaly and the conditions that led to its detection and characterization. We review various mechanisms proposed to explain the anomaly and discuss the current state of efforts to determine its nature. A comprehensive new investigation of the anomalous behavior of the two Pioneers has begun recently. The new efforts rely on the much-extended set of radio-metric Doppler data for both spacecraft in conjunction with the newly available complete record of their telemetry files and a large archive of original project documentation. As the new study is yet to report its findings, this review provides the necessary background for the new results to appear in the near future. In particular, we provide a significant amount of information on the design, operations and behavior of the two Pioneers during their entire missions, including descriptions of various data formats and techniques used for their navigation and radio-science data analysis. As most of this information was recovered relatively recently, it was not used in the previous studies of the Pioneer anomaly, but it is critical for the new investigation.

  8. Quantum Junction Solar Cells

    KAUST Repository

    Tang, Jiang

    2012-09-12

    Colloidal quantum dot solids combine convenient solution-processing with quantum size effect tuning, offering avenues to high-efficiency multijunction cells based on a single materials synthesis and processing platform. The highest-performing colloidal quantum dot rectifying devices reported to date have relied on a junction between a quantum-tuned absorber and a bulk material (e.g., TiO 2); however, quantum tuning of the absorber then requires complete redesign of the bulk acceptor, compromising the benefits of facile quantum tuning. Here we report rectifying junctions constructed entirely using inherently band-aligned quantum-tuned materials. Realizing these quantum junction diodes relied upon the creation of an n-type quantum dot solid having a clean bandgap. We combine stable, chemically compatible, high-performance n-type and p-type materials to create the first quantum junction solar cells. We present a family of photovoltaic devices having widely tuned bandgaps of 0.6-1.6 eV that excel where conventional quantum-to-bulk devices fail to perform. Devices having optimal single-junction bandgaps exhibit certified AM1.5 solar power conversion efficiencies of 5.4%. Control over doping in quantum solids, and the successful integration of these materials to form stable quantum junctions, offers a powerful new degree of freedom to colloidal quantum dot optoelectronics. © 2012 American Chemical Society.

  9. XYY chromosome anomaly and schizophrenia.

    Science.gov (United States)

    Rajagopalan, M; MacBeth, R; Varma, S L

    1998-02-07

    Sex chromosome anomalies have been associated with psychoses, and most of the evidence is linked to the presence of an additional X chromosome. We report a patient with XYY chromosome anomaly who developed schizophrenia.

  10. Discrete R Symmetries and Anomalies

    OpenAIRE

    Michael Dine(Santa Cruz Institute for Particle Physics and Department of Physics, Santa Cruz CA 95064, U.S.A.); Angelo Monteux(Santa Cruz Institute for Particle Physics, University of California Santa Cruz, 1156 High Street, Santa Cruz, U.S.A.)

    2012-01-01

    We comment on aspects of discrete anomaly conditions focussing particularly on $R$ symmetries. We review the Green-Schwarz cancellation of discrete anomalies, providing a heuristic explanation why, in the heterotic string, only the "model-independent dilaton" transforms non-linearly under discrete symmetries; this argument suggests that, in other theories, multiple fields might play a role in anomaly cancellations, further weakening any anomaly constraints at low energies. We provide examples...

  11. Anomaly-safe discrete groups

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Mu-Chun, E-mail: muchunc@uci.edu [Department of Physics and Astronomy, University of California, Irvine, CA 92697-4575 (United States); Fallbacher, Maximilian, E-mail: m.fallbacher@tum.de [Physik–Department T30, Technische Universität München, James–Franck–Straße 1, 85748 Garching (Germany); Ratz, Michael, E-mail: michael.ratz@tum.de [Physik–Department T30, Technische Universität München, James–Franck–Straße 1, 85748 Garching (Germany); Trautner, Andreas, E-mail: andreas.trautner@tum.de [Physik–Department T30, Technische Universität München, James–Franck–Straße 1, 85748 Garching (Germany); Excellence Cluster Universe, Boltzmannstraße 2, 85748 Garching (Germany); Vaudrevange, Patrick K.S., E-mail: patrick.vaudrevange@tum.de [Excellence Cluster Universe, Boltzmannstraße 2, 85748 Garching (Germany); TUM Institute for Advanced Study, Lichtenbergstraße 2a, 85748 Garching (Germany); Arnold Sommerfeld Center for Theoretical Physics, Ludwig–Maximilians–Universität München, Theresienstraße 37, 80333 München (Germany)

    2015-07-30

    We show that there is a class of finite groups, the so-called perfect groups, which cannot exhibit anomalies. This implies that all non-Abelian finite simple groups are anomaly-free. On the other hand, non-perfect groups generically suffer from anomalies. We present two different ways that allow one to understand these statements.

  12. Anomaly-safe discrete groups

    Directory of Open Access Journals (Sweden)

    Mu-Chun Chen

    2015-07-01

    Full Text Available We show that there is a class of finite groups, the so-called perfect groups, which cannot exhibit anomalies. This implies that all non-Abelian finite simple groups are anomaly-free. On the other hand, non-perfect groups generically suffer from anomalies. We present two different ways that allow one to understand these statements.

  13. Craniofacial anomalies in twins.

    Science.gov (United States)

    Keusch, C F; Mulliken, J B; Kaplan, L C

    1991-01-01

    Studies of twins provide insight into the relative contribution of genetic and environmental factors in the causality of structural anomalies. Thirty-five affected twin pairs were identified from a group of 1114 patients with congenital craniofacial deformities evaluated from 1972 to 1989. Forty-three of these 70 twins exhibited one or more craniofacial anomalies; these were analyzed for dysmorphic characteristics, zygosity, concordance, and family history. The anomalies were categorized into two groups: malformations and deformations. The malformations (n = 36) included hemifacial microsomia (n = 10), cleft lip and palate (n = 8), cleft palate (n = 4), rare facial cleft (n = 2), craniosynostosis (n = 2), Binder syndrome (n = 2), Treacher Collins syndrome (n = 2), craniopagus (n = 2), CHARGE association (n = 1), frontonasal dysplasia (n = 2), and constricted ears (n = 1). The deformations (n = 7) included plagiocephaly (n = 5), hemifacial hypoplasia (n = 1), and micrognathia (n = 1). Twenty-one monozygotic and 14 dizygotic twin pairs were identified. The concordance rate was 33 percent for monozygotic twins and 7 percent for dizygotic twins.(ABSTRACT TRUNCATED AT 250 WORDS)

  14. [Horseshoe kidney: not a simple fusion anomaly].

    Science.gov (United States)

    Caccetta, Francesco; Caroppo, Maurizio; Musio, Fernando; Mudoni, Anna; Accogli, Antonella; Zacheo, Maria Dolores; Burzo, Domenica; Bramato, Daniele; Carluccio, Giancamillo; Nuzzo, Vitale

    2015-01-01

    The horseshoe kidney is a congenital anatomical defect of the kidney that occurs in 0,25% of the population and is generally characterized by the fusion of the lower poles of the two kidneys through an isthmus and to which may be associated with urogenital and renal vascular anomalies. Asymptomatic in 1/3 of the cases and, most of time, accidentally discovered during a radiological examination, promotes nephrolithiasis, ureteropelvic junction obstruction, hydronephrosis, vesicoureteral reflux and pyelonephritis. We report two cases of patients with kidney horseshoe, characterized by the abrupt onset of a septic state with oligo-anuric acute renal failure, electrolyte and acid-base abnormalities, rapid decay of the general conditions, with detection of nephrolithiasis, hydronephrosis and acute pyelonephritis and whose clinical management resulted in a significant and synergistic nefro-urology involvment. The kidney horseshoe not represent so only a simple fusion anomaly but rather an important anatomical condition that, once diagnosed, it would be worthy of a careful clinical, radiological and laboratory surveillance, in order to prevent the potential complications that may be also particularly severe.

  15. Detecting Patterns of Anomalies

    Science.gov (United States)

    2009-03-01

    detect anomalies in the dataset is used in [Leung and Leckie, 2005] and [Eskin et al., 2002]. One-class SVMs [Li et al., 2003, Heller et al., 2003] and...IEE Proceedings F, 140(2): 107–113, 1993. J.D.F. Habbema, J. Hermans , and K. Vandenbroek. A stepwise discriminant analysis pro- gram using density...Technometrics, 29(4):409–412, 1987. K.A. Heller , K.M. Svore, A. Keromytis, and S.J. Stolfo. One class support vector machines for detecting anomalous

  16. Chiral supergravity and anomalies

    CERN Document Server

    Mielke, E W; Macias, Alfredo; Mielke, Eckehard W.

    1999-01-01

    Similarily as in the Ashtekar approach, the translational Chern-Simons term is, as a generating function, instrumental for a chiral reformulation of simple (N=1) supergravity. After applying the algebraic Cartan relation between spin and torsion, the resulting canonical transformation induces not only decomposition of the gravitational fields into selfdual and antiselfdual modes, but also a splitting of the Rarita-Schwinger fields into their chiral parts in a natural way. In some detail, we also analyze the consequences for axial and chiral anomalies.

  17. Low Risk Anomalies?

    DEFF Research Database (Denmark)

    Schneider, Paul; Wagner, Christian; Zechner, Josef

    This paper shows theoretically and empirically that beta- and volatility-based low risk anomalies are driven by return skewness. The empirical patterns concisely match the predictions of our model that endogenizes the role of skewness for stock returns through default risk. With increasing downside...... of betting against beta/volatility among low skew firms compared to high skew firms is economically large. Our results suggest that the returns to betting against beta or volatility do not necessarily pose asset pricing puzzles but rather that such strategies collect premia that compensate for skew risk...

  18. Detecting Biosphere anomalies hotspots

    Science.gov (United States)

    Guanche-Garcia, Yanira; Mahecha, Miguel; Flach, Milan; Denzler, Joachim

    2017-04-01

    The current amount of satellite remote sensing measurements available allow for applying data-driven methods to investigate environmental processes. The detection of anomalies or abnormal events is crucial to monitor the Earth system and to analyze their impacts on ecosystems and society. By means of a combination of statistical methods, this study proposes an intuitive and efficient methodology to detect those areas that present hotspots of anomalies, i.e. higher levels of abnormal or extreme events or more severe phases during our historical records. Biosphere variables from a preliminary version of the Earth System Data Cube developed within the CAB-LAB project (http://earthsystemdatacube.net/) have been used in this study. This database comprises several atmosphere and biosphere variables expanding 11 years (2001-2011) with 8-day of temporal resolution and 0.25° of global spatial resolution. In this study, we have used 10 variables that measure the biosphere. The methodology applied to detect abnormal events follows the intuitive idea that anomalies are assumed to be time steps that are not well represented by a previously estimated statistical model [1].We combine the use of Autoregressive Moving Average (ARMA) models with a distance metric like Mahalanobis distance to detect abnormal events in multiple biosphere variables. In a first step we pre-treat the variables by removing the seasonality and normalizing them locally (μ=0,σ=1). Additionally we have regionalized the area of study into subregions of similar climate conditions, by using the Köppen climate classification. For each climate region and variable we have selected the best ARMA parameters by means of a Bayesian Criteria. Then we have obtained the residuals by comparing the fitted models with the original data. To detect the extreme residuals from the 10 variables, we have computed the Mahalanobis distance to the data's mean (Hotelling's T^2), which considers the covariance matrix of the joint

  19. When do anomalies begin?

    Science.gov (United States)

    Lightman, Alan; Gingerich, Owen

    1992-02-01

    The present historical and methodological consideration of scientific anomalies notes that some of these are recognized as such, after long neglect, only after the emergence of compelling explanations for their presence in the given theory in view of an alternative conceptual framework. These cases of 'retrorecognition' are indicative not merely of a significant characteristic of the process of conceptual development and scientific discovery, but of the bases for such process in human psychology. Attention is given to the illustrative cases of the 'flatness problem' in big bang theory, the perigee-opposition problem in Ptolemaic astronomy, the continental-fit problem in geology, and the equality of inertial and gravitational mass.

  20. The diphoton anomaly

    Science.gov (United States)

    Nardecchia, M.

    2017-07-01

    In December 2015, the ATLAS and CMS Collaborations presented results from data taken at the LHC with pp collisions at the center-of-mass energy of √{s} = 13{ TeV} . In the search for resonances decaying into two photons, both experiments observed a tantalising excess of events at an invariant mass of the photon pair of 750GeV. In this contribution, I will summarise some of the main phenomenological and theoretical aspects of this anomaly in terms of New Physics.

  1. The human myotendinous junction

    DEFF Research Database (Denmark)

    Knudsen, A B; Larsen, M; Mackey, Abigail

    2015-01-01

    The myotendinous junction (MTJ) is a specialized structure in the musculotendinous system, where force is transmitted from muscle to tendon. Animal models have shown that the MTJ takes form of tendon finger-like processes merging with muscle tissue. The human MTJ is largely unknown and has never ...

  2. Doped semiconductor nanocrystal junctions

    Energy Technology Data Exchange (ETDEWEB)

    Borowik, Ł.; Mélin, T., E-mail: thierry.melin@isen.iemn.univ-lille1.fr [Institut d’Electronique, de Microélectronique et de Nanotechnologie, CNRS-UMR8520, Avenue Poincaré, F-59652 Villeneuve d’Ascq (France); Nguyen-Tran, T.; Roca i Cabarrocas, P. [Laboratoire de Physique des Interfaces et des Couches Minces, CNRS-UMR7647, Ecole Polytechnique, F-91128 Palaiseau (France)

    2013-11-28

    Semiconductor junctions are the basis of electronic and photovoltaic devices. Here, we investigate junctions formed from highly doped (N{sub D}≈10{sup 20}−10{sup 21}cm{sup −3}) silicon nanocrystals (NCs) in the 2–50 nm size range, using Kelvin probe force microscopy experiments with single charge sensitivity. We show that the charge transfer from doped NCs towards a two-dimensional layer experimentally follows a simple phenomenological law, corresponding to formation of an interface dipole linearly increasing with the NC diameter. This feature leads to analytically predictable junction properties down to quantum size regimes: NC depletion width independent of the NC size and varying as N{sub D}{sup −1/3}, and depleted charge linearly increasing with the NC diameter and varying as N{sub D}{sup 1/3}. We thus establish a “nanocrystal counterpart” of conventional semiconductor planar junctions, here however valid in regimes of strong electrostatic and quantum confinements.

  3. Junction trees of general graphs

    Institute of Scientific and Technical Information of China (English)

    Xiaofei WANG; Jianhua GUO

    2008-01-01

    In this paper,we study the maximal prime subgraphs and their corresponding structure for any undirected graph.We introduce the notion of junction trees and investigate their structural characteristics,including junction properties,induced-subtree properties,running-intersection properties and maximum-weight spanning tree properties.Furthermore,the characters of leaves and edges on junction trees are discussed.

  4. Ruptured venous aneurysm of cervicomedullary junction

    Directory of Open Access Journals (Sweden)

    Ashish Aggarwal

    2014-01-01

    Full Text Available Background: Ruptured venous aneurysm is often seen with arterio-venous malformation (AVM or developmental venous anomaly (DVA. However, isolated venous aneurysm is unusual. Case Description: We present a case of ruptured venous aneurysm that presented with subarachnoid hemorrhage (SAH and intraventricular hemorrhage (IVH. Digital substraction angiography (DSA revealed a saccular contrast filling pouch in the left lateral aspect of cervicomedullary junction (CMJ. Endovascular intervention was not a viable option. During surgery, a saccular pliable structure approx. 1.5 Χ 1 cm was found in the subarachnoid space that was clipped and excised. There were no arterial feeders, no evidence of surrounding AVM, and no dilated perimedullary vein. Conclusion: This is perhaps the first reported case of ruptured venous aneurysm (without associated AVM of CMJ, which was successfully managed surgically. The possible etiologies remain an unnoticed head trauma or a congenital vessel wall abnormality. Surgically clipping and excision remains the treatment of choice for such lesion.

  5. Quivers via anomaly chains

    Energy Technology Data Exchange (ETDEWEB)

    Casero, Roberto [Dipartimento di Fisica, Universita di Milano-Bicocca, Piazza della Scienza, 3, 20126 Milan (Italy)]. E-mail: roberto.casero@mib.infn.it; Trincherini, Enrico [Dipartimento di Fisica, Universita di Milano-Bicocca, Piazza della Scienza, 3, 20126 Milan (Italy)

    2003-09-01

    We study quivers in the context of matrix models. We introduce chains of generalized Konishi anomalies to write the quadratic and cubic equations that constrain the resolvents of general affine A-circumflex{sub n-1} and non-affine A{sub n} quiver gauge theories, and give a procedure to calculate all higher-order relations. For these theories we also evaluate, as functions of the resolvents, VEV's of chiral operators with two and four bi-fundamental insertions. As an example of the general procedure we explicitly consider the two simplest quivers A{sub 2} and A-circumflex{sub 1}, obtaining in the first case a cubic algebraic curve, and for the affine theory the same equation as that of U(N) theories with adjoint matter, successfully reproducing the RG cascade result. (author)

  6. Quivers via anomaly chains

    CERN Document Server

    Casero, R; Casero, Roberto; Trincherini, Enrico

    2003-01-01

    We study quivers in the context of matrix models. We introduce chains of generalized Konishi anomalies to write the quadratic and cubic equations that constrain the resolvents of general affine and non-affine quiver gauge theories, and give a procedure to calculate all higher-order relations. For these theories we also evaluate, as functions of the resolvents, VEV's of chiral operators with two and four bifundamental insertions. As an example of the general procedure we explicitly consider the two simplest quivers A2 and A1(affine), obtaining in the first case a cubic algebraic curve, and for the affine theory the same equation as that of U(N) theories with adjoint matter, successfully reproducing the RG cascade result.

  7. Low Risk Anomalies?

    DEFF Research Database (Denmark)

    Schneider, Paul; Wagner, Christian; Zechner, Josef

    risk, the standard capital asset pricing model (CAPM) increasingly overestimates expected equity returns relative to firms' true (skew-adjusted) market risk. Empirically, the profitability of betting against beta/volatility increases with firms' downside risk, and the risk-adjusted return differential...... of betting against beta/volatility among low skew firms compared to high skew firms is economically large. Our results suggest that the returns to betting against beta or volatility do not necessarily pose asset pricing puzzles but rather that such strategies collect premia that compensate for skew risk......This paper shows theoretically and empirically that beta- and volatility-based low risk anomalies are driven by return skewness. The empirical patterns concisely match the predictions of our model that endogenizes the role of skewness for stock returns through default risk. With increasing downside...

  8. Cubic anomalies in WMAP

    CERN Document Server

    Land, K; Land, Kate; Magueijo, Joao

    2004-01-01

    We perform a frequentist analysis of the bispectrum of WMAP first year data. We find clear signal domination up to l=200, with overall consistency with Gaussianity except for the following features. There is a flat patch (i.e. a low chi-squared region) in the same-l components of the bispectrum spanning the range l=32-62; this may be interpreted as ruling out Gaussianity at the 99.6% confidence level. There is also an asymmetry between the North and South inter-l bispectrum components at the 99% confidence level. The preferred asymmetry axis correlates well with the (l,b)=(57,10) direction quoted in the literature for asymmetries in the power spectrum and three-point correlation function. However our analysis of the quadrupole (its bispectrum and principal axes) fail to make contact with previously claimed anomalies.

  9. Holliday junction resolvases.

    Science.gov (United States)

    Wyatt, Haley D M; West, Stephen C

    2014-09-02

    Four-way DNA intermediates, called Holliday junctions (HJs), can form during meiotic and mitotic recombination, and their removal is crucial for chromosome segregation. A group of ubiquitous and highly specialized structure-selective endonucleases catalyze the cleavage of HJs into two disconnected DNA duplexes in a reaction called HJ resolution. These enzymes, called HJ resolvases, have been identified in bacteria and their bacteriophages, archaea, and eukaryotes. In this review, we discuss fundamental aspects of the HJ structure and their interaction with junction-resolving enzymes. This is followed by a brief discussion of the eubacterial RuvABC enzymes, which provide the paradigm for HJ resolvases in other organisms. Finally, we review the biochemical and structural properties of some well-characterized resolvases from archaea, bacteriophage, and eukaryotes. Copyright © 2014 Cold Spring Harbor Laboratory Press; all rights reserved.

  10. Wireless Josephson Junction Arrays

    Science.gov (United States)

    Adams, Laura

    2015-03-01

    We report low temperature, microwave transmission measurements on a wireless two- dimensional network of Josephson junction arrays composed of superconductor-insulator -superconductor tunnel junctions. Unlike their biased counterparts, by removing all electrical contacts to the arrays and superfluous microwave components and interconnects in the transmission line, we observe new collective behavior in the transmission spectra. In particular we will show emergent behavior that systematically responds to changes in microwave power at fixed temperature. Likewise we will show the dynamic and collective response of the arrays while tuning the temperature at fixed microwave power. We discuss these spectra in terms of the Berezinskii-Kosterlitz-Thouless phase transition and Shapiro steps. We gratefully acknowledge the support Prof. Steven Anlage at the University of Maryland and Prof. Allen Goldman at the University of Minnesota. Physics and School of Engineering and Applied Sciences.

  11. Congenital Anomalies of the Kidney and the Urinary Tract (CAKUT)

    Science.gov (United States)

    2014-01-01

    This article reviews the majority of Congenital Anomalies of the Kidney and Urinary Tract (CAKUT) with emphasis in Pediatric Pathology describing and illustrating lesions as varied as ureteral duplications, ureteropelvic junction obstruction, horseshoe kidney, posterior urethral valve and prune belly syndrome, obstructive renal dysplasia, nonmotile ciliopathies and several syndromes associated with renal malformations (Meckel–Joubert, short rib, Bardet–Biedl, asplenia/polysplenia, hereditary renal adysplasia, Zellweger, trisomies, VACTER-L, Potter, caudal dysplasia, and sirenomelia), as well as ADPK, and ARPK. The purpose of this review is not only to describe the congenital renal anomalies, but also to analyze the more recent therapeutic interventions that may modify the natural history of some of these severe conditions. PMID:25313840

  12. Algebraic study of chiral anomalies

    Indian Academy of Sciences (India)

    Juan Mañes; Raymond Stora; Bruno Zumino

    2012-06-01

    The algebraic structure of chiral anomalies is made globally valid on non-trivial bundles by the introduction of a fixed background connection. Some of the techniques used in the study of the anomaly are improved or generalized, including a systematic way of generating towers of ‘descent equations’.

  13. Anomaly mediation deformed by axion

    Energy Technology Data Exchange (ETDEWEB)

    Nakayama, Kazunori, E-mail: kazunori@hep-th.phys.s.u-tokyo.ac.jp [Department of Physics, University of Tokyo, Bunkyo-ku, Tokyo 113-0033 (Japan); Kavli Institute for the Physics and Mathematics of the Universe, University of Tokyo, Kashiwa 277-8583 (Japan); Yanagida, Tsutomu T. [Kavli Institute for the Physics and Mathematics of the Universe, University of Tokyo, Kashiwa 277-8583 (Japan)

    2013-05-13

    We show that in supersymmetric axion models the axion supermultiplet obtains a sizable F-term due to a non-supersymmetric dynamics and it generally gives the gaugino masses comparable to the anomaly mediation contribution. Thus the gaugino mass relation predicted by the anomaly mediation effect can be significantly modified in the presence of axion to solve the strong CP problem.

  14. What is a Timing Anomaly?

    DEFF Research Database (Denmark)

    Cassez, Franck; Hansen, Rene Rydhof; Olesen, Mads Chr.

    2012-01-01

    Timing anomalies make worst-case execution time analysis much harder, because the analysis will have to consider all local choices. It has been widely recognised that certain hardware features are timing anomalous, while others are not. However, defining formally what a timing anomaly is, has bee...

  15. Seismic data fusion anomaly detection

    Science.gov (United States)

    Harrity, Kyle; Blasch, Erik; Alford, Mark; Ezekiel, Soundararajan; Ferris, David

    2014-06-01

    Detecting anomalies in non-stationary signals has valuable applications in many fields including medicine and meteorology. These include uses such as identifying possible heart conditions from an Electrocardiography (ECG) signals or predicting earthquakes via seismographic data. Over the many choices of anomaly detection algorithms, it is important to compare possible methods. In this paper, we examine and compare two approaches to anomaly detection and see how data fusion methods may improve performance. The first approach involves using an artificial neural network (ANN) to detect anomalies in a wavelet de-noised signal. The other method uses a perspective neural network (PNN) to analyze an arbitrary number of "perspectives" or transformations of the observed signal for anomalies. Possible perspectives may include wavelet de-noising, Fourier transform, peak-filtering, etc.. In order to evaluate these techniques via signal fusion metrics, we must apply signal preprocessing techniques such as de-noising methods to the original signal and then use a neural network to find anomalies in the generated signal. From this secondary result it is possible to use data fusion techniques that can be evaluated via existing data fusion metrics for single and multiple perspectives. The result will show which anomaly detection method, according to the metrics, is better suited overall for anomaly detection applications. The method used in this study could be applied to compare other signal processing algorithms.

  16. Anomaly Mediation and Cosmology

    CERN Document Server

    Basboll, A; Jones, D R T

    2011-01-01

    We consider an extension of the MSSM wherein anomaly mediation is the source of supersymmetry-breaking, and the tachyonic slepton problem is solved by a Fayet-Iliopoulos (FI) $D$-term associated with an additional $U(1)$ symmetry, which also facilitates the see-saw mechanism for neutrino masses and a natural source for the Higgs $\\mu$-term. We explore the cosmological consequences of the model, showing that the model naturally produces a period of hybrid inflation, terminating in the production of cosmic strings. In spite of the presence of a $U(1)$ with an FI term, inflation is effected by the $F$-term, with a $D$-flat tree potential (the FI term being cancelled by non-zero squark and slepton fields). Calculating the 1-loop corrections to the inflaton potential, we estimate the constraints on the parameters of the model from Cosmic Microwave Background data. We briefly discuss the mechanisms for baryogenesis via conventional leptogenesis, the out-of-equilibrium production of neutrinos from the cosmic strings...

  17. Basilar invagination, Chiari malformation, syringomyelia: A review

    Directory of Open Access Journals (Sweden)

    Goel Atul

    2009-01-01

    Full Text Available Institute and personal experience (over 25 years of basilar invagination was reviewed. The database of the department included 3300 patients with craniovertebral junction pathology from the year 1951 till date. Patients with basilar invagination were categorized into two groups based on the presence (Group A or absence (Group B of clinical and radiological evidence of instability of the craniovertebral junction. Standard radiological parameters described by Chamberlain were used to assess the instability of the craniovertebral junction. The pathogenesis and clinical features in patients with Group A basilar invagination appeared to be related to mechanical instability, whereas it appeared to be secondary to embryonic dysgenesis in patients with Group B basilar invagination. Treatment by facetal distraction and direct lateral mass fixation can result in restoration of craniovertebral and cervical alignment in patients with Group A basilar invagination. Such a treatment can circumvent the need for transoral or posterior fossa decompression surgery. Foramen magnum bone decompression appears to be a rational surgical treatment for patients having Group B basilar invagination. The division of patients with basilar invagination on the basis of presence or absence of instability provides insight into the pathogenesis of the anomaly and a basis for rational surgical treatment.

  18. An induced junction photovoltaic cell

    Science.gov (United States)

    Call, R. L.

    1974-01-01

    Silicon solar cells operating with induced junctions rather than diffused junctions have been fabricated and tested. Induced junctions were created by forming an inversion layer near the surface of the silicon by supplying a sheet of positive charge above the surface. Measurements of the response of the inversion layer cell to light of different wavelengths indicated it to be more sensitive to the shorter wavelengths of the sun's spectrum than conventional cells. The greater sensitivity occurs because of the shallow junction and the strong electric field at the surface.

  19. Interior Alaska Bouguer Gravity Anomaly

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A 1 kilometer Complete Bouguer Anomaly gravity grid of interior Alaska. Only those grid cells within 10 kilometers of a gravity data point have gravity values....

  20. Interior Alaska Bouguer Gravity Anomaly

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A 1 kilometer Complete Bouguer Anomaly gravity grid of interior Alaska. All grid cells within the rectangular data area (from 61 to 66 degrees North latitude and...

  1. ALP hints from cooling anomalies

    CERN Document Server

    Giannotti, Maurizio

    2015-01-01

    We review the current status of the anomalies in stellar cooling and argue that, among the new physics candidates, an axion-like particle would represent the best option to account for the hinted additional cooling.

  2. Notes on Anomaly Induced Transport

    CERN Document Server

    Landsteiner, Karl

    2016-01-01

    Chiral anomalies give rise to dissipationless transport phenomena such as the chiral magnetic and vortical effects. In these notes I review the theory from a quantum field theoretic, hydrodynamic and holographic perspective. A physical interpretation of the otherwise somewhat obscure concepts of consistent and covariant anomalies will be given. Vanishing of the CME in strict equilibrium will be connected to the boundary conditions in momentum space imposed by the regularization. The role of the gravitational anomaly will be explained. That it contributes to transport in an unexpectedly low order in the derivative expansion can be easiest understood via holography. Anomalous transport is supposed to play also a key role in understanding the electronics of advanced materials, the Dirac- and Weyl (semi)metals. Anomaly related phenomena such as negative magnetoresistivity, anomalous Hall effect, thermal anomalous Hall effect and Fermi arcs can be understood via anomalous transport. Finally I briefly review a holo...

  3. Renormalization group flows and anomalies

    CERN Document Server

    Komargodski, Zohar

    2015-01-01

    This chapter reviews various aspects of renormalization group flows and anomalies. The chapter considers specific Euclidean two-dimensional theories. Namely, the theories are invariant under translations and rotations in the two space directions. Here the chapter studies theories where, if possible, certain equations hold in fact also at coincident points. In other words, the chapter looks at theories where there is no local gravitational anomaly.

  4. Situs anomalies on prenatal MRI.

    Science.gov (United States)

    Nemec, Stefan F; Brugger, Peter C; Nemec, Ursula; Bettelheim, Dieter; Kasprian, Gregor; Amann, Gabriele; Rimoin, David L; Graham, John M; Prayer, Daniela

    2012-04-01

    Situs anomalies refer to an abnormal organ arrangement, which may be associated with severe errors of development. Due regard being given to prenatal magnetic resonance imaging (MRI) as an adjunct to ultrasonography (US), this study sought to demonstrate the in utero visualization of situs anomalies on MRI, compared to US. This retrospective study included 12 fetuses with situs anomalies depicted on fetal MRI using prenatal US as a comparison modality. With an MRI standard protocol, the whole fetus was assessed for anomalies, with regard to the position and morphology of the following structures: heart; venous drainage and aorta; stomach and intestines; liver and gallbladder; and the presence and number of spleens. Situs inversus totalis was found in 3/12 fetuses; situs inversus with levocardia in 1/12 fetuses; situs inversus abdominis in 2/12 fetuses; situs ambiguous with polysplenia in 3/12 fetuses, and with asplenia in 2/12 fetuses; and isolated dextrocardia in 1/12 fetuses. Congenital heart defects (CHDs), vascular anomalies, and intestinal malrotations were the most frequent associated malformations. In 5/12 cases, the US and MRI diagnoses were concordant. Compared to US, in 7/12 cases, additional MRI findings specified the situs anomaly, but CHDs were only partially visualized in six cases. Our initial MRI results demonstrate the visualization of situs anomalies and associated malformations in utero, which may provide important information for perinatal management. Using a standard protocol, MRI may identify additional findings, compared to US, which confirm and specify the situs anomaly, but, with limited MRI visualization of fetal CHDs. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  5. Anomaly detection on cup anemometers

    Science.gov (United States)

    Vega, Enrique; Pindado, Santiago; Martínez, Alejandro; Meseguer, Encarnación; García, Luis

    2014-12-01

    The performances of two rotor-damaged commercial anemometers (Vector Instruments A100 LK) were studied. The calibration results (i.e. the transfer function) were very linear, the aerodynamic behavior being more efficient than the one shown by both anemometers equipped with undamaged rotors. No detection of the anomaly (the rotors’ damage) was possible based on the calibration results. However, the Fourier analysis clearly revealed this anomaly.

  6. Space weather and space anomalies

    Directory of Open Access Journals (Sweden)

    L. I. Dorman

    2005-11-01

    Full Text Available A large database of anomalies, registered by 220 satellites in different orbits over the period 1971-1994 has been compiled. For the first time, data from 49 Russian Kosmos satellites have been included in a statistical analysis. The database also contains a large set of daily and hourly space weather parameters. A series of statistical analyses made it possible to quantify, for different satellite orbits, space weather conditions on the days characterized by anomaly occurrences. In particular, very intense fluxes (>1000 pfu at energy >10 MeV of solar protons are linked to anomalies registered by satellites in high-altitude (>15000 km, near-polar (inclination >55° orbits typical for navigation satellites, such as those used in the GPS network, NAVSTAR, etc. (the rate of anomalies increases by a factor ~20, and to a much smaller extent to anomalies in geostationary orbits, (they increase by a factor ~4. Direct and indirect connections between anomaly occurrence and geomagnetic perturbations are also discussed.

  7. Mixing in T-junctions

    NARCIS (Netherlands)

    Kok, Jacobus B.W.; van der Wal, S.

    1996-01-01

    The transport processes that are involved in the mixing of two gases in a T-junction mixer are investigated. The turbulent flow field is calculated for the T-junction with the k- turbulence model by FLOW3D. In the mathematical model the transport of species is described with a mixture fraction

  8. Coronary Artery Anomalies in Animals

    Directory of Open Access Journals (Sweden)

    Brian A. Scansen

    2017-04-01

    Full Text Available Coronary artery anomalies represent a disease spectrum from incidental to life-threatening. Anomalies of coronary artery origin and course are well-recognized in human medicine, but have received limited attention in veterinary medicine. Coronary artery anomalies are best described in the dog, hamster, and cow though reports also exist in the horse and pig. The most well-known anomaly in veterinary medicine is anomalous coronary artery origin with a prepulmonary course in dogs, which limits treatment of pulmonary valve stenosis. A categorization scheme for coronary artery anomalies in animals is suggested, dividing these anomalies into those of major or minor clinical significance. A review of coronary artery development, anatomy, and reported anomalies in domesticated species is provided and four novel canine examples of anomalous coronary artery origin are described: an English bulldog with single left coronary ostium and a retroaortic right coronary artery; an English bulldog with single right coronary ostium and transseptal left coronary artery; an English bulldog with single right coronary ostium and absent left coronary artery with a prepulmonary paraconal interventricular branch and an interarterial circumflex branch; and a mixed-breed dog with tetralogy of Fallot and anomalous origin of all coronary branches from the brachiocephalic trunk. Coronary arterial fistulae are also described including a coronary cameral fistula in a llama cria and an English bulldog with coronary artery aneurysm and anomalous shunting vessels from the right coronary artery to the pulmonary trunk. These examples are provided with the intent to raise awareness and improve understanding of such defects.

  9. Metallic Junction Thermoelectric Device Simulations

    Science.gov (United States)

    Duzik, Adam J.; Choi, Sang H.

    2017-01-01

    Thermoelectric junctions made of semiconductors have existed in radioisotope thermoelectric generators (RTG) for deep space missions, but are currently being adapted for terrestrial energy harvesting. Unfortunately, these devices are inefficient, operating at only 7% efficiency. This low efficiency has driven efforts to make high-figure-of-merit thermoelectric devices, which require a high electrical conductivity but a low thermal conductivity, a combination that is difficult to achieve. Lowered thermal conductivity has increased efficiency, but at the cost of power output. An alternative setup is to use metallic junctions rather than semiconductors as thermoelectric devices. Metals have orders of magnitude more electrons and electronic conductivities higher than semiconductors, but thermal conductivity is higher as well. To evaluate the viability of metallic junction thermoelectrics, a two dimensional heat transfer MATLAB simulation was constructed to calculate efficiency and power output. High Seebeck coefficient alloys, Chromel (90%Ni-10%Cr) and Constantan (55%Cu-45%Ni), produced efficiencies of around 20-30%. Parameters such as the number of layers of junctions, lateral junction density, and junction sizes for both series- and parallel-connected junctions were explored.

  10. Shortening Anomalies in Supersymmetric Theories

    CERN Document Server

    Gomis, Jaume; Ooguri, Hirosi; Seiberg, Nathan; Wang, Yifan

    2016-01-01

    We present new anomalies in two-dimensional ${\\mathcal N} =(2, 2)$ superconformal theories. They obstruct the shortening conditions of chiral and twisted chiral multiplets at coincident points. This implies that marginal couplings cannot be promoted to background super-fields in short representations. Therefore, standard results that follow from ${\\mathcal N} =(2, 2)$ spurion analysis are invalidated. These anomalies appear only if supersymmetry is enhanced beyond ${\\mathcal N} =(2, 2)$. These anomalies explain why the conformal manifolds of the K3 and $T^4$ sigma models are not K\\"ahler and do not factorize into chiral and twisted chiral moduli spaces and why there are no ${\\mathcal N} =(2, 2)$ gauged linear sigma models that cover these conformal manifolds. We also present these results from the point of view of the Riemann curvature of conformal manifolds.

  11. Boundary terms of conformal anomaly

    Directory of Open Access Journals (Sweden)

    Sergey N. Solodukhin

    2016-01-01

    Full Text Available We analyze the structure of the boundary terms in the conformal anomaly integrated over a manifold with boundaries. We suggest that the anomalies of type B, polynomial in the Weyl tensor, are accompanied with the respective boundary terms of the Gibbons–Hawking type. Their form is dictated by the requirement that they produce a variation which compensates the normal derivatives of the metric variation on the boundary in order to have a well-defined variational procedure. This suggestion agrees with recent findings in four dimensions for free fields of various spins. We generalize this consideration to six dimensions and derive explicitly the respective boundary terms. We point out that the integrated conformal anomaly in odd dimensions is non-vanishing due to the boundary terms. These terms are specified in three and five dimensions.

  12. Multiple Visceral and Peritoneal Anomalies

    Directory of Open Access Journals (Sweden)

    Gayathri Prabhu S

    2016-07-01

    Full Text Available Visceral and peritoneal anomalies are frequently encountered during cadaveric dissections and surgical procedures of abdomen. A thorough knowledge of the same is required for the success of diagnostic, surgical and radiological procedures of abdomen. We report multiple peritoneal and visceral anomalies noted during dissection classes for medical undergraduates. The anomalies were found in an adult male cadaver aged approximately 70 years. The right iliac fossa was empty due to the sub-hepatic position of caecum and appendix. The sigmoid colon formed an inverted “U” shaped loop above the sacral promontory in the median position. It entered the pelvis from the right side and descended along the lateral wall of the pelvis. The sigmoid mesocolon was attached obliquely to the posterior abdominal wall, just above the sacral promontory. Further there was a cysto-colic fold of peritoneum extending from the right colic flexure. We discuss the clinical significance of the variations.

  13. Electromagnetic Duality and Entanglement Anomalies

    CERN Document Server

    Donnelly, William; Wall, Aron

    2016-01-01

    Duality is an indispensable tool for describing the strong-coupling dynamics of gauge theories. However, its actual realization is often quite subtle: quantities such as the partition function can transform covariantly, with degrees of freedom rearranged in a nonlocal fashion. We study this phenomenon in the context of the electromagnetic duality of abelian $p$-forms. A careful calculation of the duality anomaly on an arbitrary $D$-dimensional manifold shows that the effective actions agree exactly in odd $D$, while in even $D$ they differ by a term proportional to the Euler number. Despite this anomaly, the trace of the stress tensor agrees between the dual theories. We also compute the change in the vacuum entanglement entropy under duality, relating this entanglement anomaly to the duality of an "edge mode" theory in two fewer dimensions. Previous work on this subject has led to conflicting results; we explain and resolve these discrepancies.

  14. Conformal Anomalies and Gravitational Waves

    CERN Document Server

    Meissner, Krzysztof A

    2016-01-01

    We argue that the presence of conformal anomalies in gravitational theories can lead to observable modifications to Einstein's equations via the induced anomalous effective actions, whose non-localities can overwhelm the smallness of the Planck scale. The fact that no such effects have been seen in recent cosmological or gravitational wave observations therefore imposes strong restrictions on the field content of possible extensions of Einstein's theory: all viable theories should have vanishing conformal anomalies. We then show that, among presently known theories, a complete cancellation of conformal anomalies in $D=4$ for both the $C^2$ invariant and the Euler (Gauss-Bonnet) invariant $E_4$ can only be achieved for $N$-extended supergravities with $N\\geq 5$, as well as for M theory compactified to four dimensions.

  15. Boundary terms of conformal anomaly

    Energy Technology Data Exchange (ETDEWEB)

    Solodukhin, Sergey N., E-mail: Sergey.Solodukhin@lmpt.univ-tours.fr

    2016-01-10

    We analyze the structure of the boundary terms in the conformal anomaly integrated over a manifold with boundaries. We suggest that the anomalies of type B, polynomial in the Weyl tensor, are accompanied with the respective boundary terms of the Gibbons–Hawking type. Their form is dictated by the requirement that they produce a variation which compensates the normal derivatives of the metric variation on the boundary in order to have a well-defined variational procedure. This suggestion agrees with recent findings in four dimensions for free fields of various spins. We generalize this consideration to six dimensions and derive explicitly the respective boundary terms. We point out that the integrated conformal anomaly in odd dimensions is non-vanishing due to the boundary terms. These terms are specified in three and five dimensions.

  16. Boundary Anomalies and Correlation Functions

    CERN Document Server

    Huang, Kuo-Wei

    2016-01-01

    It was shown recently that boundary terms of conformal anomalies recover the universal contribution to the entanglement entropy and also play an important role in the boundary monotonicity theorem of odd-dimensional quantum field theories. Motivated by these results, we investigate relationships between boundary anomalies and the stress tensor correlation functions in conformal field theories. In particular, we focus on how the conformal Ward identity and the renormalization group equation are modified by boundary central charges. Renormalized stress tensors induced by boundary Weyl invariants are also discussed, with examples in spherical and cylindrical geometries.

  17. Imaging of cervicothoracic junction trauma

    Directory of Open Access Journals (Sweden)

    Wongwaisayawan S

    2013-01-01

    Full Text Available Sirote Wongwaisayawan,1 Ruedeekorn Suwannanon,2 Rathachai Kaewlai11Department of Radiology, Ramathibodi Hospital and Mahidol University, Bangkok, Thailand; 2Department of Radiology, Faculty of Medicine, Prince of Songkla University, Hat Yai, ThailandAbstract: Cervicothoracic junction trauma is an important cause of morbidity and mortality in trauma patients. Imaging has played an important role in identifying injuries and guiding appropriate, timely therapy. Computed tomography is currently a method of choice for diagnosing cervicothoracic junction trauma, in which the pattern of injuries often suggests possible mechanisms and potential injuries. In this article, the authors describe and illustrate common and uncommon injuries that can occur in the cervicothoracic junction.Keywords: cervicothoracic junction, cervical spine, trauma, imaging, radiology

  18. Josephson junctions with ferromagnetic interlayer

    Energy Technology Data Exchange (ETDEWEB)

    Wild, Georg Hermann

    2012-03-04

    We report on the fabrication of superconductor/insulator/ferromagnetic metal/superconductor (Nb/AlO{sub x}/Pd{sub 0.82}Ni{sub 0.18}/Nb) Josephson junctions (SIFS JJs) with high critical current densities, large normal resistance times area products, and high quality factors. For these junctions, a transition from 0- to {pi}-coupling is observed for a thickness d{sub F}=6 nm of the ferromagnetic Pd{sub 0.82}Ni{sub 0.18} interlayer. The magnetic field dependence of the critical current of the junctions demonstrates good spatial homogeneity of the tunneling barrier and ferromagnetic interlayer. Magnetic characterization shows that the Pd{sub 0.82}Ni{sub 0.18} has an out-of-plane anisotropy and large saturation magnetization indicating negligible dead layers at the interfaces. A careful analysis of Fiske modes up to about 400 GHz provides valuable information on the junction quality factor and the relevant damping mechanisms. Whereas losses due to quasiparticle tunneling dominate at low frequencies, at high frequencies the damping is explained by the finite surface resistance of the junction electrodes. High quality factors of up to 30 around 200 GHz have been achieved. They allow to study the junction dynamics, in particular the switching probability from the zero-voltage into the voltage state with and without microwave irradiation. The experiments with microwave irradiation are well explained within semi-classical models and numerical simulations. In contrast, at mK temperature the switching dynamics without applied microwaves clearly shows secondary quantum effects. Here, we could observe for the first time macroscopic quantum tunneling in Josephson junctions with a ferromagnetic interlayer. This observation excludes fluctuations of the critical current as a consequence of an unstable magnetic domain structure of the ferromagnetic interlayer and affirms the suitability of SIFS Josephson junctions for quantum information processing.

  19. Electronic thermometry in tunable tunnel junction

    Energy Technology Data Exchange (ETDEWEB)

    Maksymovych, Petro

    2016-03-15

    A tunable tunnel junction thermometry circuit includes a variable width tunnel junction between a test object and a probe. The junction width is varied and a change in thermovoltage across the junction with respect to the change in distance across the junction is determined. Also, a change in biased current with respect to a change in distance across the junction is determined. A temperature gradient across the junction is determined based on a mathematical relationship between the temperature gradient, the change in thermovoltage with respect to distance and the change in biased current with respect to distance. Thermovoltage may be measured by nullifying a thermoelectric tunneling current with an applied voltage supply level. A piezoelectric actuator may modulate the probe, and thus the junction width, to vary thermovoltage and biased current across the junction. Lock-in amplifiers measure the derivatives of the thermovoltage and biased current modulated by varying junction width.

  20. Confocal Annular Josephson Tunnel Junctions

    Science.gov (United States)

    Monaco, Roberto

    2016-09-01

    The physics of Josephson tunnel junctions drastically depends on their geometrical configurations and here we show that also tiny geometrical details play a determinant role. More specifically, we develop the theory of short and long annular Josephson tunnel junctions delimited by two confocal ellipses. The behavior of a circular annular Josephson tunnel junction is then seen to be simply a special case of the above result. For junctions having a normalized perimeter less than one, the threshold curves in the presence of an in-plane magnetic field of arbitrary orientations are derived and computed even in the case with trapped Josephson vortices. For longer junctions, a numerical analysis is carried out after the derivation of the appropriate motion equation for the Josephson phase. We found that the system is modeled by a modified and perturbed sine-Gordon equation with a space-dependent effective Josephson penetration length inversely proportional to the local junction width. Both the fluxon statics and dynamics are deeply affected by the non-uniform annulus width. Static zero-field multiple-fluxon solutions exist even in the presence of a large bias current. The tangential velocity of a traveling fluxon is not determined by the balance between the driving and drag forces due to the dissipative losses. Furthermore, the fluxon motion is characterized by a strong radial inward acceleration which causes electromagnetic radiation concentrated at the ellipse equatorial points.

  1. Global gravitational anomalies and transport

    Science.gov (United States)

    Chowdhury, Subham Dutta; David, Justin R.

    2016-12-01

    We investigate the constraints imposed by global gravitational anomalies on parity odd induced transport coefficients in even dimensions for theories with chiral fermions, gravitinos and self dual tensors. The η-invariant for the large diffeomorphism corresponding to the T transformation on a torus constraints the coefficients in the thermal effective action up to mod 2. We show that the result obtained for the parity odd transport for gravitinos using global anomaly matching is consistent with the direct perturbative calculation. In d = 6 we see that the second Pontryagin class in the anomaly polynomial does not contribute to the η-invariant which provides a topological explanation of this observation in the `replacement rule'. We then perform a direct perturbative calculation for the contribution of the self dual tensor in d = 6 to the parity odd transport coefficient using the Feynman rules proposed by Gaumé and Witten. The result for the transport coefficient agrees with that obtained using matching of global anomalies.

  2. Anomalies and noncommutative index theory

    CERN Document Server

    Perrot, D

    2006-01-01

    These are the notes of a lecture given during the summer school "Geometric and Topological Methods for Quantum Field Theory", Villa de Leyva, Colombia, july 11 - 29, 2005. We review basic facts concerning gauge anomalies and discuss the link with the Connes-Moscovici index formula in noncommutative geometry.

  3. Bony anomaly of Meckel's cave.

    Science.gov (United States)

    Tubbs, R Shane; Salter, E George; Oakes, W Jerry

    2006-01-01

    This study describes the seemingly rare occurrence of bone formation within the proximal superior aspect of Meckel's cave thus forming a bony foramen for the proximal trigeminal nerve to traverse. The anatomy of Meckel's cave is reviewed and the clinical potential for nerve compression from this bony anomaly discussed.

  4. Conformal anomalies and gravitational waves

    Science.gov (United States)

    Meissner, Krzysztof A.; Nicolai, Hermann

    2017-09-01

    We argue that the presence of conformal anomalies in gravitational theories can lead to observable modifications to Einstein's equations via the induced anomalous effective actions, whose non-localities can overwhelm the smallness of the Planck scale. The fact that no such effects have been seen in recent cosmological or gravitational wave observations therefore imposes strong restrictions on the field content of possible extensions of Einstein's theory: all viable theories should have vanishing conformal anomalies. We then show that a complete cancellation of conformal anomalies in D = 4 for both the C2 invariant and the Euler (Gauss-Bonnet) invariant E4 can only be achieved for N-extended supergravity multiplets with N ⩾ 5, as well as for M theory compactified to four dimensions. Although there remain open questions, in particular concerning the true significance of conformal anomalies in non-conformal theories, as well as their possible gauge dependence for spin s ⩾3/2, these cancellations suggest a hidden conformal structure of unknown type in these theories.

  5. Connecting Stratospheric and Ionospheric Anomalies

    Science.gov (United States)

    Spraggs, M. E.; Goncharenko, L. P.; Zhang, S.; Coster, A. J.; Benkevitch, L. V.

    2014-12-01

    This study investigates any relationship between lunar phases and ionospheric anomalies that appear at low latitudes concurrently with sudden stratospheric warmings (SSWs). The study utilizes World-wide GPS Receiver Network Total Electron Content (TEC) data spanning 13 years (2001-2014) and focuses on the changes in the equatorial ionization anomaly the Western hemisphere. TEC is highly variable due to the influences of solar flux, geomagnetic activity, and seasonal variation and these influences are removed by the use of model. This empirical TEC model is a combination of linear dependencies of solar flux (F10.7) and geomagnetic activity (Ap3) with a third degree polynomial dependency for day-of-year (DOY). With such dependencies removed, the remaining TEC variation could be resolved and attributed to an appropriate mechanism. Lunar phase and apside was investigated in particular, especially the new and full moon phases during perigees when tidal forcing would be most powerful. Lunar tidal forcing on planetary waves is also examined as being physically responsible for setting up conditions that may give rise to SSWs and ionospheric anomalies. Preliminary results suggest that such anomalies may be enhanced in intensity during the full or new moon and even more so during perigee by different amounts depending on whether the SSW is a major (40-60%) or minor (20-45%) event.

  6. Thermal anomalies in stressed Teflon.

    Science.gov (United States)

    Lee, S. H.; Wulff, C. A.

    1972-01-01

    In the course of testing polytetrafluoroethylene (Teflon) as a calorimetric gasketing material, serendipity revealed a thermal anomaly in stressed film that occurs concomitantly with the well-documented 25 C transition. The magnitude of the excess energy absorption - about 35 cal/g - is suggested to be related to the restricted thermal expansion of the film.

  7. Octagonal Defects at Carbon Nanotube Junctions

    Science.gov (United States)

    Jaskólski, W.; Pelc, M.; Chico, Leonor; Ayuela, A.

    2013-01-01

    We investigate knee-shaped junctions of semiconductor zigzag carbon nanotubes. Two dissimilar octagons appear at such junctions; one of them can reconstruct into a pair of pentagons. The junction with two octagons presents two degenerate localized states at Fermi energy (EF). The reconstructed junction has only one state near EF, indicating that these localized states are related to the octagonal defects. The inclusion of Coulomb interaction splits the localized states in the junction with two octagons, yielding an antiferromagnetic system. PMID:24089604

  8. Anomaly detection in online social networks

    CERN Document Server

    Savage, David; Yu, Xinghuo; Chou, Pauline; Wang, Qingmai

    2016-01-01

    Anomalies in online social networks can signify irregular, and often illegal behaviour. Anomalies in online social networks can signify irregular, and often illegal behaviour. Detection of such anomalies has been used to identify malicious individuals, including spammers, sexual predators, and online fraudsters. In this paper we survey existing computational techniques for detecting anomalies in online social networks. We characterise anomalies as being either static or dynamic, and as being labelled or unlabelled, and survey methods for detecting these different types of anomalies. We suggest that the detection of anomalies in online social networks is composed of two sub-processes; the selection and calculation of network features, and the classification of observations from this feature space. In addition, this paper provides an overview of the types of problems that anomaly detection can address and identifies key areas of future research.

  9. Focal skin defect, limb anomalies and microphthalmia.

    NARCIS (Netherlands)

    Jackson, K.E.; Andersson, H.C.

    2004-01-01

    We describe two unrelated female patients with congenital single focal skin defects, unilateral microphthalmia and limb anomalies. Growth and psychomotor development were normal and no brain malformation was detected. Although eye and limb anomalies are commonly associated, clinical anophthalmia and

  10. Modelling of Dual-Junction Solar Cells including Tunnel Junction

    Directory of Open Access Journals (Sweden)

    Abdelaziz Amine

    2013-01-01

    Full Text Available Monolithically stacked multijunction solar cells based on III–V semiconductors materials are the state-of-art of approach for high efficiency photovoltaic energy conversion, in particular for space applications. The individual subcells of the multi-junction structure are interconnected via tunnel diodes which must be optically transparent and connect the component cells with a minimum electrical resistance. The quality of these diodes determines the output performance of the solar cell. The purpose of this work is to contribute to the investigation of the tunnel electrical resistance of such a multi-junction cell through the analysis of the current-voltage (J-V characteristics under illumination. Our approach is based on an equivalent circuit model of a diode for each subcell. We examine the effect of tunnel resistance on the performance of a multi-junction cell using minimization of the least squares technique.

  11. Prevalence of dental anomalies in orthodontic patients.

    Science.gov (United States)

    Thongudomporn, U; Freer, T J

    1998-12-01

    The prevalence of dental anomalies including agenesis, crown shape, tooth position, root shape, and invagination were examined in 111 orthodontic patients; 74.77 per cent of the patients exhibited at least one dental anomaly. Invagination was found to be the most prevalent anomaly, whereas supernumerary teeth and root dilaceration were the least frequent anomalies. Dental invagination and short or blunt roots were significantly more prevalent in females than in males. Implications for orthodontic treatment planning are discussed.

  12. [Ectopia cordis and cardiac anomalies].

    Science.gov (United States)

    Cabrera, Alberto; Rodrigo, David; Luis, María Teresa; Pastor, Esteban; Galdeano, José Miguel; Esteban, Susana

    2002-11-01

    Ectopia cordis is a rare disease that occurs in 5.5 to 7.9 per million live births. Only 267 cases had been reported as of 2001, most (95%) associated with other cardiac anomalies. We studied the cardiac malformations associated in 6 patients with ectopia cordis. Depending on where the defect was located, the cases of ectopia were classified into four groups: cervical, thoracic, thoraco-abdominal, and abdominal. All 6 patients died before the third day of life, 4 during delivery. Three of the patients were included in the thoracic group, whereas the other 3 belonged to the thoraco-abdominal group. All the patients had associated ventricular septal defects, 3 double-outlet right ventricle (50%) and the rest (50%) tetralogy of Fallot-pulmonary atresia. Two patients with double-outlet right ventricle presented mitral-valve pathology, a parachute valve and an atresic mitral valve. None of these cardiac anomalies have been reported to date.

  13. On Anomaly Mediated SUSY Breaking

    CERN Document Server

    de Alwis, S P

    2008-01-01

    A discrepancy between the Anomaly Mediated Supersymmetry Breaking (AMSB) gaugino mass calculated from the work of Kaplunovsky and Louis (hep-th/9402005) (KL) and other calculations in the literature is explained, and it is argued that the KL expression is the correct one relevant to the Wilsonian action. Furthermore it is argued that the AMSB contribution to the squark and slepton masses should be replaced by the contribution pointed out by Dine and Seiberg (DS) which has nothing to do with Weyl anomalies. This is not in general equivalent to the AMSB expression, and it is shown that there are models in which the usual AMSB expression would vanish but the DS one is non-zero. In fact the latter has aspects of both AMSB and gauge mediated SUSY breaking. In particular like the latter, it gives positive squared masses for sleptons.

  14. Survey of Anomaly Detection Methods

    Energy Technology Data Exchange (ETDEWEB)

    Ng, B

    2006-10-12

    This survey defines the problem of anomaly detection and provides an overview of existing methods. The methods are categorized into two general classes: generative and discriminative. A generative approach involves building a model that represents the joint distribution of the input features and the output labels of system behavior (e.g., normal or anomalous) then applies the model to formulate a decision rule for detecting anomalies. On the other hand, a discriminative approach aims directly to find the decision rule, with the smallest error rate, that distinguishes between normal and anomalous behavior. For each approach, we will give an overview of popular techniques and provide references to state-of-the-art applications.

  15. Theory of Geological Anomaly in Remote Sensing

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Geological anomaly is geological body or complex body with obviously different compositions, structures or orders of genesis as compared with those in the surrounding areas. Geological anomaly, restrained by the geological factors closely associated with ore-forming process, is an important clue to ore deposits. The geological anomaly serves as a geological sign to locate ore deposits. Therefore, it is very important to study how to define the characteristics of geological anomaly and further to locate the changes in these characteristics. In this paper, the authors propose the geological anomaly based on the remote-sensing images and data, and expound systematically such image features as scale, size, boundary, morphology and genesis of geological anomalies. Then the authors introduce the categorization of the geological anomalies according to their geneses. The image characteristics of some types of geological anomalies, such as the underground geological anomaly, are also explained in detail. Based on the remote-sensing interpretation of these geological anomalies, the authors conclude that the forecasting and exploration of ore deposits should be focused on the following three aspects: (1) the analysis of geological setting and geological anomaly; (2) the analysis of circular geological anomaly, and (3) the comprehensive forecasting of ore deposits and the research into multi-source information.

  16. Fetal renal anomalies : diagnosis, management, and outcome

    NARCIS (Netherlands)

    Damen-Elias, Henrica Antonia Maria

    2004-01-01

    In two to three percent of fetuses structural anomalies can be found with prenatal ultrasound investigation. Anomalies of the urinary tract account for 15 to 20% of these anomalies with a detection rate of approximately of 90%. In Chapter 2, 3 and 4 we present reference curves for size and growth of

  17. Fetal renal anomalies : diagnosis, management, and outcome

    NARCIS (Netherlands)

    Damen-Elias, Henrica Antonia Maria

    2004-01-01

    In two to three percent of fetuses structural anomalies can be found with prenatal ultrasound investigation. Anomalies of the urinary tract account for 15 to 20% of these anomalies with a detection rate of approximately of 90%. In Chapter 2, 3 and 4 we present reference curves for size and growth

  18. Bifid rib: A rare anomaly

    Directory of Open Access Journals (Sweden)

    Mythili Krishnan Rathinasabapathi

    2015-01-01

    Full Text Available A case of the bifid rib was found during routine bone study. The distal part of the osseous rib bifurcated into two divisions with an angle of 60°. Both divisions had their own costal cartilage. Bifid rib is a congenital abnormality of the rib cage and usually asymptomatic, often discovered incidentally on chest X-ray. Effects of this neuroskeletal anomaly can include respiratory difficulties and neurological limitations.

  19. Sharing AIS Related Anomalies (SARA)

    Science.gov (United States)

    2016-03-01

    misconfiguration and intentional misuse. These unintended behaviours generate an abundance of anomalies that the security community has an interest in monitoring...Lastly, the feedback loop formed with clients is essential to SARA’s advancement. The more SARA is exposed, the better and faster it can be adapted...to end-user needs and thus be adopted by them. This section is organised as follows : • Section 2.1 describes the strategy used to identify potential

  20. Anomaly mediation in superstring theory

    Energy Technology Data Exchange (ETDEWEB)

    Conlon, J.P. [Rudolf Peierls Center for Theoretical Physics, 1 Keble Road, Oxford, OX1 3NP (United Kingdom); Balliol College, Oxford, OX1 3BJ (United Kingdom); Kavli Institute of Theoretical Physics, Kohn Hall, University of California, Santa Barbara CA 93106-4030 (United States); Goodsell, M. [Deutsches Elektronen-Synchrotron DESY, Notkestrasse 85, 22603 Hamburg (Germany); Palti, E. [Centre de Physique Theorique, Ecole Polytechnique, CNRS, 91128 Palaiseau (France)

    2011-01-15

    We study anomaly mediated supersymmetry breaking in type IIB string theory and use our results to test the supergravity formula for anomaly mediated gaugino masses. We compute 1-loop gaugino masses for models of D3-branes on orbifold singularities with 3-form fluxes by calculating the annulus correlator of 3-form flux and two gauginos in the zero momentum limit. Consistent with supergravity expectations we find both anomalous and running contributions to 1-loop gaugino masses. For background Neveu-Schwarz H-flux we find an exact match with the supergravity formula. For Ramond-Ramond flux there is an off-shell ambiguity that precludes a full matching. The anomaly mediated gaugino masses, while determined by the infrared spectrum, arise from an explicit sum over UV open string winding modes. We also calculate brane-to-brane tree-level gravity mediated gaugino masses and show that there are two contributions coming from the dilaton and from the twisted modes, which are suppressed by the full T{sup 6} volume and the untwisted T{sup 2} volume respectively. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  1. Anomaly mediation in superstring theory

    Energy Technology Data Exchange (ETDEWEB)

    Conlon, Joseph P. [Rudolf Peierls Center for Theoretical Physics, Oxford (United Kingdom); Balliol College, Oxford (United Kingdom); Goodsell, Mark [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Palti, Eran [Centre de Physique Theoretique, Ecole Polytechnique, CNRS, Palaiseau (France)

    2010-08-15

    We study anomaly mediated supersymmetry breaking in type IIB string theory and use our results to test the supergravity formula for anomaly mediated gaugino masses. We compute 1-loop gaugino masses for models of D3-branes on orbifold singularities with 3-form fluxes by calculating the annulus correlator of 3-form flux and two gauginos in the zero momentum limit. Consistent with supergravity expectations we find both anomalous and running contributions to 1-loop gaugino masses. For background Neveu-Schwarz H-flux we find an exact match with the supergravity formula. For Ramond-Ramond flux there is an off-shell ambiguity that precludes a full matching. The anomaly mediated gaugino masses, while determined by the infrared spectrum, arise from an explicit sum over UV open string winding modes. We also calculate brane-to-brane tree-level gravity mediated gaugino masses and show that there are two contributions coming from the dilaton and from the twisted modes, which are suppressed by the full T{sup 6} volume and the untwisted T{sup 2} volume respectively. (orig.)

  2. Columbus Payloads Flow Rate Anomalies

    Science.gov (United States)

    Quaranta, Albino; Bufano, Gaetana; DePalo, Savino; Holt, James M.; Szigetvari, Zoltan; Palumberi, Sergio; Hinderer, S.

    2011-01-01

    The Columbus Active Thermal Control System (ATCS) is the main thermal bus for the pressurized racks working inside the European laboratory. One of the ATCS goals is to provide proper water flow rate to each payload (P/L) by controlling actively the pressure drop across the common plenum distribution piping. Overall flow measurement performed by the Water Pump Assembly (WPA) is the only flow rate monitor available at system level and is not part of the feedback control system. At rack activation the flow rate provided by the system is derived on ground by computing the WPA flow increase. With this approach, several anomalies were raised during these 3 years on-orbit, with the indication of low flow rate conditions on the European racks FSL, BioLab, EDR and EPM. This paper reviews the system and P/Ls calibration approach, the anomalies occurred, the engineering evaluation on the measurement approach and the accuracy improvements proposed, the on-orbit test under evaluation with NASA and finally discusses possible short and long term solutions in case of anomaly confirmation.

  3. Trace anomalies from quantum mechanics

    CERN Document Server

    Bastianelli, F; Bastianelli, Fiorenzo; Nieuwenhuizen, Peter van

    1993-01-01

    The 1-loop anomalies of a d-dimensional quantum field theory can be computed by evaluating the trace of the regulated path integral jacobian matrix, as shown by Fujikawa. In 1983, Alvarez-Gaum\\'e and Witten observed that one can simplify this evaluation by replacing the operators which appear in the regulator and in the jacobian by quantum mechanical operators with the same (anti)commutation relations. By rewriting this quantum mechanical trace as a path integral with periodic boundary conditions for a one-dimensional supersymmetric nonlinear sigma model, they obtained the chiral anomalies for spin 1/2 and 3/2 fields and selfdual antisymmetric tensors in d dimensions. In this article, we treat the case of trace anomalies for spin 0, 1/2 and 1 fields in a gravitational and Yang-Mills background. We do not introduce a supersymmetric sigma model, but keep the original Dirac matrices $\\g^\\m$ and internal symmetry generators $T^a$ in the path integral. As a result, we get a matrix-valued action. Gauge covariance o...

  4. Astrometric Solar-System Anomalies

    CERN Document Server

    Anderson, John D

    2009-01-01

    There are at least four unexplained anomalies connected with astrometric data. Perhaps the most disturbing is the fact that when a spacecraft on a flyby trajectory approaches the Earth within 2000 km or less, it often experiences a change in total orbital energy per unit mass. Next, a secular change in the astronomical unit AU is definitely a concern. It is increasing by about 15 cm yr$^{-1}$. The other two anomalies are perhaps less disturbing because of known sources of nongravitational acceleration. The first is an apparent slowing of the two Pioneer spacecraft as they exit the solar system in opposite directions. Some astronomers and physicists are convinced this effect is of concern, but many others are convinced it is produced by a nearly identical thermal emission from both spacecraft, in a direction away from the Sun, thereby producing acceleration toward the Sun. The fourth anomaly is a measured increase in the eccentricity of the Moon's orbit. Here again, an increase is expected from tidal friction ...

  5. Gap junctions - guards of excitability.

    Science.gov (United States)

    Stroemlund, Line Waring; Jensen, Christa Funch; Qvortrup, Klaus; Delmar, Mario; Nielsen, Morten Schak

    2015-06-01

    Cardiomyocytes are connected by mechanical and electrical junctions located at the intercalated discs (IDs). Although these structures have long been known, it is becoming increasingly clear that their components interact. This review describes the involvement of the ID in electrical disturbances of the heart and focuses on the role of the gap junctional protein connexin 43 (Cx43). Current evidence shows that Cx43 plays a crucial role in organizing microtubules at the intercalated disc and thereby regulating the trafficking of the cardiac sodium channel NaV1.5 to the membrane.

  6. Global Anomalies and Effective Field Theory

    CERN Document Server

    Golkar, Siavash

    2015-01-01

    We show that matching anomalies under large gauge transformations and large diffeomorphisms can explain the appearance and non-renormalization of couplings in effective field theory. We focus on %thermal partition functions and thermal effective field theory where we argue that the appearance of certain unusual Chern-Simons couplings is a consequence of global anomalies. As an example, we show that a mixed global anomaly in four dimensions fixes the chiral vortical effect coefficient. This is an experimentally measurable prediction from a global anomaly. For certain situations, we propose a simpler method for calculating global anomalies which uses correlation functions rather than eta invariants.

  7. Algorithms for Anomaly Detection - Lecture 2

    CERN Document Server

    CERN. Geneva

    2017-01-01

    The concept of statistical anomalies, or outliers, has fascinated experimentalists since the earliest attempts to interpret data. We want to know why some data points don’t seem to belong with the others: perhaps we want to eliminate spurious or unrepresentative data from our model. Or, the anomalies themselves may be what we are interested in: an outlier could represent the symptom of a disease, an attack on a computer network, a scientific discovery, or even an unfaithful partner. We start with some general considerations, such as the relationship between clustering and anomaly detection, the choice between supervised and unsupervised methods, and the difference between global and local anomalies. Then we will survey the most representative anomaly detection algorithms, highlighting what kind of data each approach is best suited to, and discussing their limitations. We will finish with a discussion of the difficulties of anomaly detection in high-dimensional data and some new directions for anomaly detec...

  8. Algorithms for Anomaly Detection - Lecture 1

    CERN Document Server

    CERN. Geneva

    2017-01-01

    The concept of statistical anomalies, or outliers, has fascinated experimentalists since the earliest attempts to interpret data. We want to know why some data points don’t seem to belong with the others: perhaps we want to eliminate spurious or unrepresentative data from our model. Or, the anomalies themselves may be what we are interested in: an outlier could represent the symptom of a disease, an attack on a computer network, a scientific discovery, or even an unfaithful partner. We start with some general considerations, such as the relationship between clustering and anomaly detection, the choice between supervised and unsupervised methods, and the difference between global and local anomalies. Then we will survey the most representative anomaly detection algorithms, highlighting what kind of data each approach is best suited to, and discussing their limitations. We will finish with a discussion of the difficulties of anomaly detection in high-dimensional data and some new directions for anomaly detec...

  9. Major congenital anomalies in a Danish region

    DEFF Research Database (Denmark)

    Garne, Ester; Hansen, Anne Vinkel; Birkelund, Anne Sofie

    2014-01-01

    congenital anomaly, 13.9% had a chromosomal anomaly and 7.7% were multiple congenital anomalies. The combined foetal and infant mortality in the study area was 11.6 per 1,000 births. 19% (2.2 per 1,000) of these deaths were foetuses and infants with major congenital anomalies. Combined foetal and infant......INTRODUCTION: This study describes the prevalence of congenital anomalies and changes over time in birth outcome, mortality and chronic maternal diseases. MATERIAL AND METHODS: This study was based on population data from the EUROCAT registry covering the Funen County, Denmark, 1995......-2008. The registry covers live births, foetal deaths with a gestational age (GA) of 20 weeks or more, and terminations of pregnancy due to congenital anomalies (TOPFA). RESULTS: The overall prevalence of congenital anomalies was 2.70% (95% confidence interval: 2.58-2.80). The majority of cases had an isolated...

  10. Control over Rectification in Supramolecular Tunneling Junctions

    NARCIS (Netherlands)

    Wimbush, K.S.; Wimbush, Kim S.; Reus, William F.; van der Wiel, Wilfred Gerard; Reinhoudt, David; Whitesides, George M.; Nijhuis, C.A.; Velders, Aldrik

    2010-01-01

    In complete control: The magnitude of current rectification in well-defined supramolecular tunneling junctions can be controlled by changing the terminal functionality (red spheres) of dendrimers (gray spheres) immobilized on a supramolecular platform (see picture). Junctions containing biferrocene

  11. Nano-Molecular Junctions on STM Tips

    Institute of Scientific and Technical Information of China (English)

    Chun Huang∗; Jianshu Yang

    2011-01-01

    We present a technique for building metal-organic-metal junctions, which contain ten or fewer conjugated molecules between each of such junction, and the investigations of the I-V response of these junctions. The junctions are made by self assembling thiolated molecules onto gold coated tips for use in scanning tunneling microscopy. We show that this easy technique probes the qualitative properties of the molecules. Current-voltage characteristics of a Tour wire and a new molecular rectifier are presented.

  12. Nano-Molecular Junctions on STM Tips

    Institute of Scientific and Technical Information of China (English)

    Chun Huang; Jianshu Yang

    2011-01-01

    We present a technique for building metal-organic-metal junctions, which contain ten or fewer conjugated molecules between each of such junction, and the investigations of the I-V response of these junctions.The junctions are made by self assembling thiolated molecules onto gold coated tips for use in scanning tunneling microscopy. We show that this easy technique probes the qualitative properties of the molecules. Currentvoltage characteristics of a Tour wire and a new molecular rectifier are presented.

  13. Current noise in tunnel junctions

    Energy Technology Data Exchange (ETDEWEB)

    Frey, Moritz; Grabert, Hermann [Physikalisches Institut, Universitaet Freiburg, Hermann-Herder-Strasse 3, 79104, Freiburg (Germany)

    2017-06-15

    We study current fluctuations in tunnel junctions driven by a voltage source. The voltage is applied to the tunneling element via an impedance providing an electromagnetic environment of the junction. We use circuit theory to relate the fluctuations of the current flowing in the leads of the junction with the voltage fluctuations generated by the environmental impedance and the fluctuations of the tunneling current. The spectrum of current fluctuations is found to consist of three parts: a term arising from the environmental Johnson-Nyquist noise, a term due to the shot noise of the tunneling current and a third term describing the cross-correlation between these two noise sources. Our phenomenological theory reproduces previous results based on the Hamiltonian model for the dynamical Coulomb blockade and provides a simple understanding of the current fluctuation spectrum in terms of circuit theory and properties of the average current. Specific results are given for a tunnel junction driven through a resonator. (copyright 2016 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  14. Josephson tunnel junction microwave attenuator

    DEFF Research Database (Denmark)

    Koshelets, V. P.; Shitov, S. V.; Shchukin, A. V.

    1993-01-01

    A new element for superconducting electronic circuitry-a variable attenuator-has been proposed, designed, and successfully tested. The principle of operation is based on the change in the microwave impedance of a superconductor-insulator-superconductor (SIS) Josephson tunnel junction when dc bias...

  15. Congenital anomalies in Primorsky region.

    Science.gov (United States)

    Kiku, P; Voronin, S; Golokhvast, K

    2015-01-01

    According to WHO hereditary diseases and congenital malformations contribute significantly to the health of population. Thus, the problems of epidemiology, clinical presentation, diagnosis and treatment of congenital abnormalities are of interest for many researchers [2]. In addition, the dynamic accounting for the incidence of congenital malformations and hereditary diseases allows the researchers to assess the ecological situation in the region [1]. The occurrence of congenital anomalies in the world varies; it depends heavily on how carefully the data is collected [4]. Multifactorial or polygenic diseases develop under the influence of environmental factors in the presence of defective genes. They can constitute up to 90% of all chronic pathology [2-5]. To determine the incidence of congenital anomalies under the influence of environmental factors. The study used the methodology of system evaluation of congenital anomalies incidence in Primorsky region, depending on bio-climatic and environmental conditions. The authors used health statistics for the period from 2000 to 2014, F.12 class for congenital abnormalities in adolescents and children that were compared in geographical and temporal aspects with environmental factors of 33 settlements in Primorsky region. The environment is represented by nature and climate (6 factor modules) and sanitation (7 factor modules) blocks of factors. When formalizing the information database of the environment a specially developed 10-point assessment scale was used. Statistical processing of the information was carried out using Pearson's chi-squared test and multiple regression method from SSPS application program package. The study found that over the 15-year period the level of congenital abnormalities in children increased by 27.5% and in adolescents - by 35.1%, and in 2014 it amounted to 1687.6 and 839.3 per 100 000 people, respectively. The predictive model shows a steady further growth of this pathology. The incidence

  16. Stability of large-area molecular junctions

    NARCIS (Netherlands)

    Akkerman, Hylke B.; Kronemeijer, Auke J.; Harkema, Jan; van Hal, Paul A.; Smits, Edsger C. P.; de Leeuw, Dago M.; Blom, Paul W. M.

    The stability of molecular junctions is crucial for any application of molecular electronics. Degradation of molecular junctions when exposed to ambient conditions is regularly observed. In this report the stability of large-area molecular junctions under ambient conditions for more than two years

  17. Soliton bunching in annular Josephson junctions

    DEFF Research Database (Denmark)

    Vernik, I.V; Lazarides, Nickos; Sørensen, Mads Peter

    1996-01-01

    By studying soliton (fluxon) motion in long annular Josephson junctions it is possible to avoid the influence of the boundaries and soliton-soliton collisions present in linear junctions. A new experimental design consisting of a niobium coil placed on top of an annular junction has been used...

  18. Long Range Magnetic Interaction between Josephson Junctions

    DEFF Research Database (Denmark)

    Grønbech-Jensen, Niels; Samuelsen, Mogens Rugholm

    1995-01-01

    A new model for magnetic coupling between long Josephson junctions is proposed. The coupling mechanism is a result of the magnetic fields outside the junctions and is consequently effective over long distances between junctions. We give specific expressions for the form and magnitude of the inter...

  19. Dynamics of pi-junction interferometer circuits

    DEFF Research Database (Denmark)

    Kornkev, V.K.; Mozhaev, P.B.; Borisenko, I.V.;

    2002-01-01

    The pi-junction superconducting circuit dynamics was studied by means of numerical simulation technique. Parallel arrays consisting of Josephson junctions of both 0- and pi-type were studied as a model of high-T-c grain-boundary Josephson junction. The array dynamics and the critical current...

  20. Dynamics of pi-junction interferometer circuits

    DEFF Research Database (Denmark)

    Kornkev, V.K.; Mozhaev, P.B.; Borisenko, I.V.

    2002-01-01

    The pi-junction superconducting circuit dynamics was studied by means of numerical simulation technique. Parallel arrays consisting of Josephson junctions of both 0- and pi-type were studied as a model of high-T-c grain-boundary Josephson junction. The array dynamics and the critical current...

  1. Chiral Anomaly in Contorted Spacetimes

    CERN Document Server

    Mielke, E W

    1999-01-01

    The Dirac equation in Riemann-Cartan spacetimes with torsion is reconsidered. As is well-known, only the axial covector torsion $A$, a one-form, couples to massive Dirac fields. Using diagrammatic techniques, we show that besides the familiar Riemannian term only the Pontrjagin type four-form $dA\\wedge dA$ does arise additionally in the chiral anomaly, but not the Nieh-Yan term $d ^* A$, as has been claimed recently. Implications for cosmic strings in Einstein-Cartan theory as well as for Ashtekar's canonical approach to quantum gravity are discussed.

  2. Endocrine disruptors and congenital anomalies

    Directory of Open Access Journals (Sweden)

    Mônica Rittler

    2002-04-01

    Full Text Available The specialized literature was reviewed concerning the suspected increasing secular trends in the frequency of female births, male genital congenital anomalies, abnormal sperm counts, and testicular cancer. Although no risk factors could be identified yet, the observed sex ratio decline during the last decades has been considered to be an effect of certain pollutants on normal hormone activity, and human reproductive development. Reported increasing trends in the frequencies of hypospadias and cryptorchidism are very difficult to be interpreted due to the large variability in the registered frequency of these malformations due to operational as well as biological reasons.

  3. Recognising serious umbilical cord anomalies.

    Science.gov (United States)

    Marshall, Andrew S J; Jayapal, Sathiya S K; Whitburn, Jessica A S; Akinbiyi, Bolutito A; Willetts, Ian E

    2013-11-27

    Umbilical vessel catheterisation is a common intervention in neonatal care. Many complications are recognised, some of which are life-threatening. We report the case of a term neonate who was compromised at birth following antepartum haemorrhage with evidence of multiorgan ischaemic injury. Following resuscitation and umbilical vessel catheterisation, she developed pneumoperitoneum. At laparotomy, a patent vitellointestinal duct was identified and resected. Intestinal perforation was found in the duct wall, most plausibly explained by the unintentional catheterisation of the duct via the umbilicus. Learning to recognise umbilical cord anomalies, such as patent vitellointestinal duct, can be simple and could prevent potentially serious complications.

  4. Hot Flow Anomalies at Venus

    Science.gov (United States)

    Collinson, G. A.; Sibeck, David Gary; Boardsen, Scott A.; Moore, Tom; Barabash, S.; Masters, A.; Shane, N.; Slavin, J.A.; Coates, A.J.; Zhang, T. L.; Sarantos, M.

    2012-01-01

    We present a multi-instrument study of a hot flow anomaly (HFA) observed by the Venus Express spacecraft in the Venusian foreshock, on 22 March 2008, incorporating both Venus Express Magnetometer and Analyzer of Space Plasmas and Energetic Atoms (ASPERA) plasma observations. Centered on an interplanetary magnetic field discontinuity with inward convective motional electric fields on both sides, with a decreased core field strength, ion observations consistent with a flow deflection, and bounded by compressive heated edges, the properties of this event are consistent with those of HFAs observed at other planets within the solar system.

  5. Application of magnetic resonance urography in diagnosis of congenital urogenital anomalies in children.

    Science.gov (United States)

    Payabvash, Seyedmehdi; Kajbafzadeh, Abdol-Mohammad; Saeedi, Parisa; Sadeghi, Zhina; Elmi, Azadeh; Mehdizadeh, Mehrzad

    2008-09-01

    Magnetic resonance urography (MRU) has become a useful adjuvant in evaluating urogenital anomalies. In present study, we evaluated the ability of MRU in diagnosis of different congenital urogenital anomalies when the results of conventional imaging modalities were inconclusive. A total of 90 children were included in this series. The children were evaluated with T2-weighted and contrast-enhanced T1-weighted MRU sequences. The results were compared with findings obtained with ultrasonography, intravenous urography, renal nuclide scan, and voiding cystourethrography. MRU was requested in these children because conventional imaging modalities were equivocal or a co-existing urogenital anomaly was suspected. Only those cases that underwent surgery were included in this study and the surgical findings were set as the reference standard in statistical evaluation. The records of 61 boys with mean (range) age of 2.3 years (2 months-12 years) and 29 girls with mean (range) age of 3.3 years (3 months-12 years) were reviewed. The final diagnosis was ureteropelvic junction obstruction (n = 25), vesicoureteral junction obstruction (n = 16), ureterocele (n = 19), ectopic kidney (n = 11), posterior urethral valve (n = 17), and polycystic kidney (n = 2). The overall sensitivity of MRU, intravenous urography, renal nuclide scan, ultrasonography, and voiding cystourethrography in diagnosis of the aforementioned anomalies were 86, 63, 50, 44, and 41%, respectively. MRU was much more sensitive than other imaging modalities in diagnosis of end-ureteral dilation (100%) and ureterocele (89%). MRU provides a reliable noninvasive technique for imaging of the congenital anomalies in the urinary tract of children with T2-weighted MRU sequences providing unenhanced static-water images of the urinary tract as well as depicting adjacent soft-tissue lesions, and T1-weighted MRU technique imitating conventional intravenous urography. Both MRU sequences can be combined for a comprehensive

  6. Treatment of craniovertebral anormalies through occipitocervical fusion by inter-diploe screw fixation%枕骨板障间螺钉固定枕颈融合术治疗颅颈部畸形

    Institute of Scientific and Technical Information of China (English)

    姚女兆; 王文军; 王麓山; 晏怡果; 王程; 朱一平

    2014-01-01

    Objective To explore the clinical outcome of the treatment of craniovertebral anormalies through occipitocervical fusion by inter-diploe screw fixation.Methods From January 2010 to January 2013,15 patients (9 males,6 females) in the First Affiliated Hospital of University of South China were diagnosed with craniovertebral anormalies.The age ranged from 29 to 60 years (40.4 ± 8.2) years.Eight patients had Arnold-Chiari deformitory,5 patients had basilar invagination with os odontoidem,2 patients had Klippel-Feil deformitory.All the patients had symptoms of spinal medulla compression.The Japanese orthopaedic association(JOA) score of preoperation ranged from 6 to 10 (8.1 ± 1.7).All the patients received head-shoulders traction through modified Halo-vest for 1-2 weeks.All cases received occipitocervical fusion by inter-diploe screw-rod-pedicel screw system.Results All patients underwent this technique operation successfully.The mean operation time was 100-220 min (140.2 ± 30.5) min,and blood loose was 190-710 ml(272.2 ±73.4) ml.There was no neurological function worsen and severely complications.The JOA after operation 3 days was 9-14 (11.0 ± 2.1),there was statistical differences compared to preoperation (t =0.003,P < 0.05).The postoperatively radological films indicated all the inter-diploe screw locations were satisfactory,there was no screw penetrating the medial occipital plate.All cases were followed up for 12-36 months(22.0 ± 6.3) months.Bone graft fusion was obtained in 3-9 months (5.1 ± 2.7) months.There was no internal fixation breakage and loosening.The JOA score of last follow-up was 12-16 (14.1 ± 1.6),there was statistical differences compared to preoperation(t =0.002,P < 0.05).All patients with limb numbness,muscle weakness and other symptoms were obviously improved than preoperation.Conclusions Occipitocervical fusion using inter-diploe screw-rod-pedicel screw system,is an effective method for the treatment of craniovertebral anormalies with

  7. A study of dental anomalies

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Sook; Kim, Jae Duck [Dept. of Oral Radiology, College of Dentistry, Chosun University, Kwangju (Korea, Republic of)

    1993-08-15

    The purpose of this study was to find out the prevalence of dental anomalies in 600 normal persons (male:363, female:237) at age 14 to 39 years, through history taking, oral examination, and radiographic observations of subjects. The obtained results were as follows: 1. The prevalence of individual dental anomalies were as follows; Congenitally missing teeth 7%; supernumerary teeth 1.33%; ectopic eruption 8.50%; transposition 0.33%; rotation 23.67%; microdontia 11.16% (peg lateral is 5.33%; third molar 5.83%); prolonged retention of deciduous teeth 1.33%; crowding 49.83%; and spacing 15.17%. 2. Alterations in numbers of teeth : The most frequently missing teeth were mandibular lateral incisors, followed by mandibular second premolars and maxillary second premolars. In numbers of congenitally missing teeth per person, 52.38% had one missing tooth and 30.95% had two missing teeth. In supernumerary teeth, there was higher rate in male than in female. Most supernumerary teeth were mesiodens of median area in maxilla and the eruption pattern of that teeth generally was unerupted state. 3. In transposition, exchange of position of teeth involved the canine and first premolar. 4. Congenital missing rate of permanent successors in prolonged retention of deciduous teeth was 69.23%. 5. Crowding and spacing had respectively higher rate in mandible and in maxilla.

  8. Multimodality imaging of vascular anomalies.

    Science.gov (United States)

    Restrepo, Ricardo

    2013-03-01

    Vascular malformations and hemangiomas are common in children but remain a source of confusion during diagnosis, in part because of the lack of a uniform terminology. With the existing treatments for hemangiomas and vascular malformations, it is important to make the correct diagnosis initially to prevent adverse physical and emotional sequelae in not only the child but also the family. The diagnosis of vascular malformations is made primarily by the clinician and based on the physical exam. Imaging is carried out using predominantly ultrasound (US) and magnetic resonance imaging (MRI), which are complementary modalities. In most cases of vascular anomalies, US is the first line of imaging as it is readily available, less expensive, lacks ionizing radiation and does not require sedation. MRI is also of great help for further characterizing the lesions. Conventional arteriography is reserved for cases that require therapeutic intervention, more commonly for arteriovenous malformations. Radiographs usually play no role in diagnosing vascular anomalies in children. In this article, the author describes the terminology and types of hemangiomas and vascular malformations and their clinical, histological features, as well as the imaging approach and appearance.

  9. Junctional neurulation: a unique developmental program shaping a discrete region of the spinal cord highly susceptible to neural tube defects.

    Science.gov (United States)

    Dady, Alwyn; Havis, Emmanuelle; Escriou, Virginie; Catala, Martin; Duband, Jean-Loup

    2014-09-24

    In higher vertebrates, the primordium of the nervous system, the neural tube, is shaped along the rostrocaudal axis through two consecutive, radically different processes referred to as primary and secondary neurulation. Failures in neurulation lead to severe anomalies of the nervous system, called neural tube defects (NTDs), which are among the most common congenital malformations in humans. Mechanisms causing NTDs in humans remain ill-defined. Of particular interest, the thoracolumbar region, which encompasses many NTD cases in the spine, corresponds to the junction between primary and secondary neurulations. Elucidating which developmental processes operate during neurulation in this region is therefore pivotal to unraveling the etiology of NTDs. Here, using the chick embryo as a model, we show that, at the junction, the neural tube is elaborated by a unique developmental program involving concerted movements of elevation and folding combined with local cell ingression and accretion. This process ensures the topological continuity between the primary and secondary neural tubes while supplying all neural progenitors of both the junctional and secondary neural tubes. Because it is distinct from the other neurulation events, we term this phenomenon junctional neurulation. Moreover, the planar-cell-polarity member, Prickle-1, is recruited specifically during junctional neurulation and its misexpression within a limited time period suffices to cause anomalies that phenocopy lower spine NTDs in human. Our study thus provides a molecular and cellular basis for understanding the causality of NTD prevalence in humans and ascribes to Prickle-1 a critical role in lower spinal cord formation.

  10. Octagonal Defects at Carbon Nanotube Junctions

    Directory of Open Access Journals (Sweden)

    W. Jaskólski

    2013-01-01

    Full Text Available We investigate knee-shaped junctions of semiconductor zigzag carbon nanotubes. Two dissimilar octagons appear at such junctions; one of them can reconstruct into a pair of pentagons. The junction with two octagons presents two degenerate localized states at Fermi energy (EF. The reconstructed junction has only one state near EF, indicating that these localized states are related to the octagonal defects. The inclusion of Coulomb interaction splits the localized states in the junction with two octagons, yielding an antiferromagnetic system.

  11. Fabrication of high quality ferromagnetic Josephson junctions

    Energy Technology Data Exchange (ETDEWEB)

    Weides, M. [Institute for Solid State Research, Research Centre Juelich, D-52425 Juelich (Germany) and CNI-Center of Nanoelectronic Systems for Information Technology, Research Centre Juelich, D-52425 Juelich (Germany)]. E-mail: m.weides@fz-juelich.de; Tillmann, K. [Institute for Solid State Research, Research Centre Juelich, D-52425 Juelich (Germany); Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons, Research Centre Juelich, D-52425 Juelich (Germany); Kohlstedt, H. [Institute for Solid State Research, Research Centre Juelich, D-52425 Juelich (Germany); CNI-Center of Nanoelectronic Systems for Information Technology, Research Centre Juelich, D-52425 Juelich (Germany); Department of Material Science and Engineering and Department of Physics, University of Berkeley, CA 94720 (United States)

    2006-05-15

    We present ferromagnetic Nb/Al{sub 2}O{sub 3}/Ni{sub 60}Cu{sub 40}/Nb Josephson junctions (SIFS) with an ultrathin Al{sub 2}O{sub 3} tunnel barrier. The junction fabrication was optimized regarding junction insulation and homogeneity of current transport. Using ion-beam-etching and anodic oxidation we defined and insulated the junction mesas. The additional 2 nm thin Cu-layer below the ferromagnetic NiCu (SINFS) lowered interface roughness and ensured very homogeneous current transport. A high yield of junctional devices with j {sub c} spreads less than 2% was obtained.

  12. Quasiparticle current and phase locking of intrinsic Josephson junctions

    Science.gov (United States)

    Seidel, P.; Grib, A. N.; Shukrinov, Yu. M.; Scherbel, J.; Hübner, U.; Schmidl, F.

    2001-09-01

    On the base of our experiments on thin film Josephson junctions in mesa geometry we discuss the quasiparticle branches of the intrinsic arrays within a tunnelling model using d-wave superconductor density of states. We find temperature dependent current contributions and a zero bias anomaly. The coherent behaviour is studied for intrinsic arrays with an additional side-wall shunt. The existence of thresholds of phase locking at small as well as at large inductances is demonstrated. We discuss the problems with experimental realisation of the shunts as well as with an alternative concept to enhance phase locking in such arrays towards application as oscillators in the frequency range up to some THz.

  13. Selective permeability of gap junction channels.

    Science.gov (United States)

    Goldberg, Gary S; Valiunas, Virginijus; Brink, Peter R

    2004-03-23

    Gap junctions mediate the transfer of small cytoplasmic molecules between adjacent cells. A family of gap junction proteins exist that form channels with unique properties, and differ in their ability to mediate the transfer of specific molecules. Mutations in a number of individual gap junction proteins, called connexins, cause specific human diseases. Therefore, it is important to understand how gap junctions selectively move molecules between cells. Rules that dictate the ability of a molecule to travel through gap junction channels are complex. In addition to molecular weight and size, the ability of a solute to transverse these channels depends on its net charge, shape, and interactions with specific connexins that constitute gap junctions in particular cells. This review presents some data and interpretations pertaining to mechanisms that govern the differential transfer of signals through gap junction channels.

  14. Electromagnetic field anomalies above an isometric depression

    Science.gov (United States)

    Golubtsova, N. S.

    1981-12-01

    The paper examines the three-dimensional simulation of the electromagnetic field above an isometric depression with conducting deposits. The model makes it possible to study the development of electromagnetic anomalies over such a depression and to make qualitative as well as quantitative assessments of the dependence of electromagnetic anomalies on field frequency, the dimensions of geoelectric inhomogeneities, and the specific resistance of the foundation of the depression. The present approach can be used in geoelectric and magnetotelluric studies of electromagnetic anomalies.

  15. Network anomaly detection a machine learning perspective

    CERN Document Server

    Bhattacharyya, Dhruba Kumar

    2013-01-01

    With the rapid rise in the ubiquity and sophistication of Internet technology and the accompanying growth in the number of network attacks, network intrusion detection has become increasingly important. Anomaly-based network intrusion detection refers to finding exceptional or nonconforming patterns in network traffic data compared to normal behavior. Finding these anomalies has extensive applications in areas such as cyber security, credit card and insurance fraud detection, and military surveillance for enemy activities. Network Anomaly Detection: A Machine Learning Perspective presents mach

  16. Peters anomaly: review of the literature.

    Science.gov (United States)

    Bhandari, Ramanath; Ferri, Sara; Whittaker, Beatrice; Liu, Margaret; Lazzaro, Douglas R

    2011-08-01

    Peters anomaly is a rare dramatic finding at birth and can be associated with other systemic malformations. We performed a literature review of multiple case reports and case series to better define the common characteristics and unusual findings associated with Peters anomaly. A representative case is discussed followed by a literature review of multiple case reports and case series. The literature search was conducted for the years 1969 to 2009. Cases and case series were included in the review of published English ophthalmic literature. Cases were excluded if no information was reported on ocular and systemic malformations or if no information was reported on surgical interventions or outcomes. In addition, if cases did not report laterality of the lesion, they were excluded from the review. Fifty-eight cases were found that fit the above criteria, and the relevant cases were reviewed to better characterize the systemic malformations, interventions, and outcomes associated with Peters anomaly reported in the literature. Fifty-eight cases of Peters anomaly were reviewed. Of those cases reporting sex, 56% were men and 44% of cases were women. In terms of laterality, 67.2% of cases were bilateral versus 32.8% of cases that were unilateral. Moreover, bilateral cases of Peters anomaly were associated with a higher rate of systemic malformations (71.8%) versus unilateral Peters anomaly (36.8%). This difference was significant (P anomaly type I (87.5%), as opposed to those patients with Peters anomaly type II (14.2%) (P anomaly are presented. Cornea specialists who care for pediatric patients should be aware of the common and uncommon associations with Peters anomaly. Although bilateral Peters anomaly is much more commonly associated with systemic malformations, we believe that all patients with Peters anomaly should be screened for systemic malformations by both pediatricians and geneticists and undergo chromosomal analysis and molecular genetic testing.

  17. Anomaly Detection from Hyperspectral Remote Sensing Imagery

    Directory of Open Access Journals (Sweden)

    Qiandong Guo

    2016-12-01

    Full Text Available Hyperspectral remote sensing imagery contains much more information in the spectral domain than does multispectral imagery. The consecutive and abundant spectral signals provide a great potential for classification and anomaly detection. In this study, two real hyperspectral data sets were used for anomaly detection. One data set was an Airborne Visible/Infrared Imaging Spectrometer (AVIRIS data covering the post-attack World Trade Center (WTC and anomalies are fire spots. The other data set called SpecTIR contained fabric panels as anomalies compared to their background. Existing anomaly detection algorithms including the Reed–Xiaoli detector (RXD, the blocked adaptive computation efficient outlier nominator (BACON, the random selection based anomaly detector (RSAD, the weighted-RXD (W-RXD, and the probabilistic anomaly detector (PAD are reviewed here. The RXD generally sets strict assumptions to the background, which cannot be met in many scenarios, while BACON, RSAD, and W-RXD employ strategies to optimize the estimation of background information. The PAD firstly estimates both background information and anomaly information and then uses the information to conduct anomaly detection. Here, the BACON, RSAD, W-RXD, and PAD outperformed the RXD in terms of detection accuracy, and W-RXD and PAD required less time than BACON and RSAD.

  18. MRI of central nervous system anomalies

    Energy Technology Data Exchange (ETDEWEB)

    Izawa, M.; Oikawa, A.; Matoba, A.

    1987-05-01

    MRI was very useful in the evaluation of congenital anomalies of central nervous system as well as other nervous system disease with three-dimensional spatial resolution. We had experienced MRI of central nervous system anomalies, demonstrated characterisitic findings in each anomaly. MRI is useful to observe the coronal, horizontal and sagittal images of the brain and spinal cord in order to discuss the etiological mechanisms of spinal dysraphysm and its associated anomalies. In case of spina bifida cystica MRI was available to decide operative indication for radical operation and tetherd cord developed from postoperative scar or accompanied intraspinal lesions.

  19. Vascular anomalies: differential diagnosis and mimickers.

    Science.gov (United States)

    Garzon, Maria C; Weitz, Nicole; Powell, Julie

    2016-09-01

    Vascular anomalies are very common in children and encompass a wide spectrum of diseases. Many vascular anomalies can be mistaken for infantile hemangioma (IH). In addition, there is a variety of rare disorders including benign and malignant tumors that may mimic IH and other types of vascular anomalies. Understanding the clinical features, natural history, and typical clinical course of different types of vascular anomalies is essential in order to make the correct diagnosis and guide management. Radiologic imaging plays an important role in establishing the diagnosis; and when the diagnosis remains in doubt, a biopsy performed by a surgical specialist with expertise may prove to be lifesaving.

  20. The "Parity" Anomaly On An Unorientable Manifold

    CERN Document Server

    Witten, Edward

    2016-01-01

    The "parity" anomaly -- more accurately described as an anomaly in time-reversal or reflection symmetry -- arises in certain theories of fermions coupled to gauge fields and/or gravity in a spacetime of odd dimension. The "parity" anomaly has traditionally been studied on orientable manifolds only, but recent developments involving topological superconductors have made it clear that one can get more information by asking what happens on an unorientable manifold. In this paper, we analyze the "parity" anomaly for fermions coupled to gauge fields and gravity in $2+1$ dimensions. We consider applications to gapped boundary states of a topological superconductor and to M2-branes in string/M-theory.

  1. Anomaly-free sets of fermions

    Energy Technology Data Exchange (ETDEWEB)

    Batra, Puneet; /Argonne; Dobrescu, Bogdan A.; /Fermilab; Spivak, David; /UC, Berkeley, Math. Dept.

    2005-10-01

    We present new techniques for finding anomaly-free sets of fermions. Although the anomaly cancellation conditions typically include cubic equations with integer variables that cannot be solved in general, we prove by construction that any chiral set of fermions can be embedded in a larger set of fermions which is chiral and anomaly-free. Applying these techniques to extensions of the Standard Model, we find anomaly-free models that have arbitrary quark and lepton charges under an additional U(1) gauge group.

  2. Consistent anomalies of the induced W gravities

    CERN Document Server

    Abud, M; Cappiello, L

    1995-01-01

    The BRST anomaly which may be present in the induced W_n gravity quantized on the light-cone is evaluated in the geometrical framework of Zucchini. The cocycles linked by the cohomology of the BRST operator to the anomaly are straightforwardly calculated thanks to the analogy between this formulation and the Yang-Mills theory. We give also a conformally covariant formulation of these quantities including the anomaly, which is valid on arbitrary Riemann surfaces. The example of the W_3 theory is discussed and a comparison with other candidates for the anomaly available in the literature is presented.

  3. The prevalence of congenital anomalies in Europe

    DEFF Research Database (Denmark)

    Dolk, Helen; Loane, Maria; Garne, Ester

    2010-01-01

    anomalies overwhelmingly concern children surviving the early neonatal period, who have important medical, social or educational needs. The prevalence of chromosomal anomalies was 3.6 per 1,000 births, contributing 28% of stillbirths/fetal deaths from 20 weeks gestation with congenital anomaly, and 48...... of 23.9 per 1,000 births for 2003-2007. 80% were livebirths. 2.5% of livebirths with congenital anomaly died in the first week of life. 2.0% were stillbirths or fetal deaths from 20 weeks gestation. 17.6% of all cases were terminations of pregnancy following prenatal diagnosis (TOPFA). Thus, congenital...

  4. Anomaly-Free Sets of Fermions

    CERN Document Server

    Batra, P; Spivak, D; Batra, Puneet; Dobrescu, Bogdan A.; Spivak, David

    2006-01-01

    We present new techniques for finding anomaly-free sets of fermions. Although the anomaly cancellation conditions typically include cubic equations with integer variables that cannot be solved in general, we prove by construction that any chiral set of fermions can be embedded in a larger set of fermions which is chiral and anomaly-free. Applying these techniques to extensions of the Standard Model, we find anomaly-free models that have arbitrary quark and lepton charges under an additional U(1) gauge group.

  5. Spectral Methods for Magnetic Anomalies

    Science.gov (United States)

    Parker, R. L.; Gee, J. S.

    2013-12-01

    Spectral methods, that is, those based in the Fourier transform, have long been employed in the analysis of magnetic anomalies. For example, Schouten and MaCamy's Earth filter is used extensively to map patterns to the pole, and Parker's Fourier transform series facilitates forward modeling and provides an efficient algorithm for inversion of profiles and surveys. From a different, and perhaps less familiar perspective, magnetic anomalies can be represented as the realization of a stationary stochastic process and then statistical theory can be brought to bear. It is vital to incorporate the full 2-D power spectrum, even when discussing profile data. For example, early analysis of long profiles failed to discover the small-wavenumber peak in the power spectrum predicted by one-dimensional theory. The long-wavelength excess is the result of spatial aliasing, when energy leaks into the along-track spectrum from the cross-track components of the 2-D spectrum. Spectral techniques may be used to improve interpolation and downward continuation of survey data. They can also evaluate the reliability of sub-track magnetization models both across and and along strike. Along-strike profiles turn out to be surprisingly good indicators of the magnetization directly under them; there is high coherence between the magnetic anomaly and the magnetization over a wide band. In contrast, coherence is weak at long wavelengths on across-strike lines, which is naturally the favored orientation for most studies. When vector (or multiple level) measurements are available, cross-spectral analysis can reveal the wavenumber interval where the geophysical signal resides, and where noise dominates. One powerful diagnostic is that the phase spectrum between the vertical and along-path components of the field must be constant 90 degrees. To illustrate, it was found that on some very long Project Magnetic lines, only the lowest 10% of the wavenumber band contain useful geophysical signal. In this

  6. Seebeck effect in molecular junctions

    Science.gov (United States)

    Zimbovskaya, Natalya A.

    2016-05-01

    Advances in the fabrication and characterization of nanoscale systems presently allow for a better understanding of their thermoelectric properties. As is known, the building blocks of thermoelectricity are the Peltier and Seebeck effects. In the present work we review results of theoretical studies of the Seebeck effect in single-molecule junctions and similar systems. The behavior of thermovoltage and thermopower in these systems is controlled by several factors including the geometry of molecular bridges, the characteristics of contacts between the bridge and the electrodes, the strength of the Coulomb interactions between electrons on the bridge, and of electron-phonon interactions. We describe the impact of these factors on the thermopower. Also, we discuss a nonlinear Seebeck effect in molecular junctions.

  7. Electron transport in molecular junctions

    DEFF Research Database (Denmark)

    Jin, Chengjun

    This thesis addresses the electron transport in molecular junctions, focusing on the energy level alignment and correlation effects. Various levels of theory have been applied to study the structural and electronic effects in different molecular junctions, starting from the single particle density...... charge position are in quantitative agreement with the experiments, while pure DFT is not. This is the consequence of the accurate energy level alignment, where the DFT+∑ method corrects the self-interaction error in the standard DFT functional and uses a static image charge model to include the image...... charge effect on the energy level renormalization. Additionally, the gating of the 4,4’-bipyridine (44BP) molecule contacted to either Ni or Au electrodes has been investigated. Here it is found that the gating mechanism is conceptually different between two cases. In the case of Ni contacts where...

  8. How coherent are Josephson junctions?

    CERN Document Server

    Paik, Hanhee; Bishop, Lev S; Kirchmair, G; Catelani, G; Sears, A P; Johnson, B R; Reagor, M J; Frunzio, L; Glazman, L; Schoelkopf, R J

    2011-01-01

    Attaining sufficient coherence is a requirement for realizing a large-scale quantum computer. We present a new implementation of a superconducting transmon qubit that is strongly coupled to a three-dimensional superconducting cavity. We observe a reproducible increase in the coherence times of qubit (both $T_1$ and $T_2$ > 10 microseconds) and cavity ($T_{cav}$ ~ 50 microseconds) by more than an order of magnitude compared to the current state-of-art superconducting qubits. This enables the study of the stability and quality of Josephson junctions at precisions exceeding one part per million. Surprisingly, we see no evidence for $1/f$ critical current noise. At elevated temperatures, we observe the dissipation due to a small density (< 1 - 10 ppm) of thermally-excited quasiparticles. The results suggest that the overall quality of Josephson junctions will allow error rates of a few $10^{-4}$, approaching the error correction threshold.

  9. Morphogenesis of rat myotendinous junction.

    Science.gov (United States)

    Curzi, Davide; Ambrogini, Patrizia; Falcieri, Elisabetta; Burattini, Sabrina

    2013-10-01

    Myotendinous junction (MTJ) is the highly specialized complex which connects the skeletal muscle to the tendon for transmitting the contractile force between the two tissues. The purpose of this study was to investigate the MTJ development and rat EDL was chosen as a model. 1, 15, 30 day animals were considered and the junctions were analyzed by light and electron microscopy. The MTJ interface architecture increased during the development, extending the interaction between muscle and tendon. 1-day-old rats showed disorganized myofibril bundles, spread cytosol and incomplete rough endoplasmic reticulum, features partially improved in 15-day-old rats, and completely developed in 30-day-old animals. These findings indicate that muscle-tendon interface displays, during rat lifetime, numerically increased and longer tendon interdigitations, correlated with an improved organization of both tissues and with a progressive acquirement of full functionality.

  10. Thermoelectric efficiency of molecular junctions

    Science.gov (United States)

    Perroni, C. A.; Ninno, D.; Cataudella, V.

    2016-09-01

    Focus of the review is on experimental set-ups and theoretical proposals aimed to enhance thermoelectric performances of molecular junctions. In addition to charge conductance, the thermoelectric parameter commonly measured in these systems is the thermopower, which is typically rather low. We review recent experimental outcomes relative to several junction configurations used to optimize the thermopower. On the other hand, theoretical calculations provide estimations of all the thermoelectric parameters in the linear and non-linear regime, in particular of the thermoelectric figure of merit and efficiency, completing our knowledge of molecular thermoelectricity. For this reason, the review will mainly focus on theoretical studies analyzing the role of not only electronic, but also of the vibrational degrees of freedom. Theoretical results about thermoelectric phenomena in the coherent regime are reviewed focusing on interference effects which play a significant role in enhancing the figure of merit. Moreover, we review theoretical studies including the effects of molecular many-body interactions, such as electron-vibration couplings, which typically tend to reduce the efficiency. Since a fine tuning of many parameters and coupling strengths is required to optimize the thermoelectric conversion in molecular junctions, new theoretically proposed set-ups are discussed in the conclusions.

  11. Congenital anomalies surveillance in Canada.

    Science.gov (United States)

    Lowry, R Brian

    2008-01-01

    Congenital anomalies (CA) are present in approximately 3% of all newborn babies and account for about 12% of paediatric hospital admissions. They represent an important public health problem. Surveillance is especially important so that preventive measures such as folic acid fortification can be properly assessed without resorting to a series of ad hoc studies. Canada's surveillance of CAs is weak, with only Alberta and British Columbia having established sytems. Most provinces have perinatal systems but their CA data are incomplete and they do not capture terminations of pregnancy. The same is true of the Public Health Agency of Canada's system. A new system, the Fetal Alert Network, has been proposed for Ontario, which represents a start but will require additional sources of ascertainment if it is to be a truly population-based system for Ontario.

  12. GRAVITY ANOMALIES OF THE MOON

    Directory of Open Access Journals (Sweden)

    S. G. Pugacheva

    2015-01-01

    Full Text Available The source of gravity anomalies of the Moon are large mascons with a high mass concentration at a depth of volcanic plains and lunar Maria. New data on the gravitational field of the Moon were obtained from two Grail spacecrafts. The article presents the data of physical and mechanical properties of the surface soil layer of the lunar Maria and gives an assessment of the chemical composition of the soil. There have been calculated heterogeneity parameters of the surface macro-relief of the lunar Maria: albedo, soil density, average grain diameter of the particles forming the surface layer and the volume fraction occupied by particles. It can be assumed that mascons include rich KREEP rocks with a high content of thorium and iron oxide. Formation of mascons is connected with intensive development of basaltic volcanism on the Moon in the early periods of its existence.

  13. Anomalous Fraunhofer interference in epitaxial superconductor-semiconductor Josephson junctions

    Science.gov (United States)

    Suominen, H. J.; Danon, J.; Kjaergaard, M.; Flensberg, K.; Shabani, J.; Palmstrøm, C. J.; Nichele, F.; Marcus, C. M.

    2017-01-01

    We investigate patterns of critical current as a function of perpendicular and in-plane magnetic fields in superconductor-semiconductor-superconductor (SNS) junctions based on InAs/InGaAs heterostructures with an epitaxial Al layer. This material system is of interest due to its exceptionally good superconductor-semiconductor coupling, as well as large spin-orbit interaction and g factor in the semiconductor. Thin epitaxial Al allows the application of large in-plane field without destroying superconductivity. For fields perpendicular to the junction, flux focusing results in aperiodic node spacings in the pattern of critical currents known as Fraunhofer patterns by analogy to the related interference effect in optics. Adding an in-plane field yields two further anomalies in the pattern. First, higher-order nodes are systematically strengthened, indicating current flow along the edges of the device, as a result of confinement of Andreev states driven by an induced flux dipole; second, asymmetries in the interference appear that depend on the field direction and magnitude. A model is presented, showing good agreement with experiment, elucidating the roles of flux focusing, Zeeman and spin-orbit coupling, and disorder in producing these effects.

  14. Chaos induced by coupling between Josephson junctions

    Science.gov (United States)

    Shukrinov, Yu. M.; Azemtsa-Donfack, H.; Botha, A. E.

    2015-02-01

    It is found that, in a stack of intrinsic Josephson junctions in layered high temperature superconductors under external electromagnetic radiation, the chaotic features are triggered by interjunction coupling, i.e., the coupling between different junctions in the stack. While the radiation is well known to produce chaotic effects in the single junction, the effect of interjunction coupling is fundamentally different and it can lead to the onset of chaos via a different route to that of the single junction. A precise numerical study of the phase dynamics of intrinsic Josephson junctions, as described by the CCJJ+DC model, is performed. We demonstrate the charging of superconducting layers, in a bias current interval corresponding to a Shapiro step subharmonic, due to the creation of a longitudinal plasma wave along the stack of junctions. With increase in radiation amplitude chaotic behavior sets in. The chaotic features of the coupled Josephson junctions are analyzed by calculations of the Lyapunov exponents. We compare results for a stack of junctions to the case of a single junction and prove that the observed chaos is induced by the coupling between the junctions. The use of Shapiro step subharmonics may allow longitudinal plasma waves to be excited at low radiation power.

  15. [Remodeling of cardiac gap junctions and arrhythmias].

    Science.gov (United States)

    Yu, Zhi-Bin; Sheng, Juan-Juan

    2011-12-25

    In the heart, gap junctions mediate electrical and chemical coupling between adjacent cardiomyocytes, forming the cell-to-cell pathways for orderly spread of the wave of electrical excitation responsible for a functional syncytium. Three principal connexins are expressed in cardiomyocytes, connexin 43 (CX43), CX40, and CX45. CX43 predominates in ventricular muscle cells. Most of the gap junctions, assembled from CX43, are located at the intercalated discs, often with larger junctional plaques at the disc periphery. The gap junctions are rarely distributed to the sides of the cardiomyocyte. The ischemia-reperfusion, cardiac hypertrophy, heart failure, hypercholesterolemia, and diabetes mellitus induce gap junction remodeling. The gap junction remodeling induced by above-mentioned diseases shows similar characteristics, including down-regulation of CX43, reduction in gap junction plaque size, increased heterogeneity and lateralization of gap junction distribution, and dephosphorylation of CX43. The elevated angiotensin II concentration in local myocardium may play an important role in the gap junction remodeling. The down-regulation of CX43 and lateralization of gap junction distribution alter anisotropic spread of the impulse of ventricular myocardium. The dephosphorylation of CX43 not only reduces electrical conductance, but also decreases permeability of chemicals between cardiomyocytes. The lateralization of gap junctions may increase the number of hemichannels formed by CX43. The opening of hemichannels induces ATP efflux and Na(+) influx, which forms a delayed after-depolarization. The gap junction remodeling in pathological condition produces arrhythmia substrate in the ventricles. In this review, the current knowledge on the relationship between the remodeling of cardiac gap junctions and arrhythmias were summarized.

  16. Magnitude Anomalies and Propagation of Local Phases

    Science.gov (United States)

    1983-01-31

    statistically significant variation of magnitude anomalies versus one of this above parameters. A contrario, we observed a significant dependance between...enough to demand a more detailed analysis. III - Local dependance of magnitude anomalies. A smoothing of our data on all quakes originating in the same

  17. Anomalies of Nuclear Criticality, Revision 6

    Energy Technology Data Exchange (ETDEWEB)

    Clayton, E. D.; Prichard, Andrew W.; Durst, Bonita E.; Erickson, David; Puigh, Raymond J.

    2010-02-19

    This report is revision 6 of the Anomalies of Nuclear Criticality. This report is required reading for the training of criticality professionals in many organizations both nationally and internationally. This report describes many different classes of nuclear criticality anomalies that are different than expected.

  18. Improved prenatal detection of chromosomal anomalies

    DEFF Research Database (Denmark)

    Frøslev-Friis, Christina; Hjort-Pedersen, Karina; Henriques, Carsten U;

    2011-01-01

    Prenatal screening for karyotype anomalies takes place in most European countries. In Denmark, the screening method was changed in 2005. The aim of this study was to study the trends in prevalence and prenatal detection rates of chromosome anomalies and Down syndrome (DS) over a 22-year period....

  19. Remarks on Global Anomalies in RCFT Orientifolds

    CERN Document Server

    Gato-Rivera, Beatriz

    2006-01-01

    We check the list of supersymmetric standard model orientifold spectra of Dijkstra, Huiszoon and Schellekens for the presence of global anomalies, using probe branes. Absence of global anomalies is found to impose strong constraints, but in nearly all cases they are automatically satisfied by the solutions to the tadpole cancellation conditions.

  20. Coronary CTA assessment of coronary anomalies.

    NARCIS (Netherlands)

    Pursnani, A.; Jacobs, J.E.; Saremi, F.; Levisman, J.; Makaryus, A.N.; Capunay, C.; Rogers, I.S.; Wald, C.; Azmoon, S.; Stathopoulos, I.A.; Srichai, M.B.

    2012-01-01

    Coronary anomalies occur in <1% of the general population and can range from a benign incidental finding to the cause of sudden cardiac death. The coronary anomalies are classified here according to the traditional grouping into those of origin and course, intrinsic arterial anatomy, and

  1. Effective action for supersymmetric chiral anomaly

    Energy Technology Data Exchange (ETDEWEB)

    Krivoshchekov, V.K.; Chekhov, L.O.

    1987-05-01

    It is shown that consistency conditions of the type of the Wess-Zumino conditions are necessary and sufficient conditions for local integrability of the supersymmetric chiral anomaly. It follows from the requirement of global integrability that the coefficient of the anomalous action is discrete. Explicit expressions are obtained for consistent anomalies and the corresponding functionals, which depend on superfields of various types.

  2. Coronary CTA assessment of coronary anomalies.

    NARCIS (Netherlands)

    Pursnani, A.; Jacobs, J.E.; Saremi, F.; Levisman, J.; Makaryus, A.N.; Capunay, C.; Rogers, I.S.; Wald, C.; Azmoon, S.; Stathopoulos, I.A.; Srichai, M.B.

    2012-01-01

    Coronary anomalies occur in <1% of the general population and can range from a benign incidental finding to the cause of sudden cardiac death. The coronary anomalies are classified here according to the traditional grouping into those of origin and course, intrinsic arterial anatomy, and terminat

  3. Seasonality of congenital anomalies in Europe

    DEFF Research Database (Denmark)

    Luteijn, Johannes Michiel; Dolk, Helen; Addor, Marie-Claude;

    2014-01-01

    with influenza. RESULTS: We detected statistically significant seasonality in prevalence of anomalies previously associated with influenza, but the conception peak was in June (2.4% excess). We also detected seasonality in congenital cataract (April conceptions, 27%), hip dislocation and/or dysplasia (April, 12......%), congenital hydronephrosis (July, 12%), urinary defects (July, 5%), and situs inversus (December, 36%), but not for nonchromosomal anomalies combined, chromosomal anomalies combined, or other anomalies analyzed. CONCLUSION: We have confirmed previously described seasonality for congenital cataract and hip......BACKGROUND: This study describes seasonality of congenital anomalies in Europe to provide a baseline against which to assess the impact of specific time varying exposures such as the H1N1 pandemic influenza, and to provide a comprehensive and recent picture of seasonality and its possible relation...

  4. Regional magnetic anomaly constraints on continental rifting

    Science.gov (United States)

    Vonfrese, R. R. B.; Hinze, W. J.; Olivier, R.; Bentley, C. R.

    1985-01-01

    Radially polarized MAGSAT anomalies of North and South America, Europe, Africa, India, Australia and Antarctica demonstrate remarkably detailed correlation of regional magnetic lithospheric sources across rifted margins when plotted on a reconstruction of Pangea. These major magnetic features apparently preserve their integrity until a superimposed metamorphoric event alters the magnitude and pattern of the anomalies. The longevity of continental scale magnetic anomalies contrasts markedly with that of regional gravity anomalies which tend to reflect predominantly isostatic adjustments associated with neo-tectonism. First observed as a result of NASA's magnetic satellite programs, these anomalies provide new and fundamental constraints on the geologic evolution and dynamics of the continents and oceans. Accordingly, satellite magnetic observations provide a further tool for investigating continental drift to compliment other lines of evidence in paleoclimatology, paleontology, paleomagnetism, and studies of the radiometric ages and geometric fit of the continents.

  5. KIDNEY ANOMALIES: HORSE SHOE KIDNEY

    Directory of Open Access Journals (Sweden)

    Hemalatha

    2015-03-01

    Full Text Available INTRODUCTION : Horse Shoe Kidney was first recognized during an autopsy by De Carpi in 1521. This anomaly consists of two distinct renal masses lying vertically on either side of the midline and connected at their respective lower poles by a parenchymatous or fibrous isthmus that crosses the mid pl ane of the body. This isthmus lies at the level of 4th lumbar vertebra just beneath the origin of inferior mesenteric artery in about 40% of cases. Fusion of upper poles instead of the lower poles results in a n inverted horse Shoe Kidney which constitute 5 - 10% of ail Horse - Shoe kidneys , (i.e. in 95% of HSK , fusion is at lower poles. HSK is found more commonly in males by a 2 : 1 margin. AIM OF STUDY : An attempt has been made to know the various anomalies . The study has been taken up with the fond hope of helping the clinician , sonologist , and surgeons during their routine work. To apply this knowledge to the incoming post graduates in their research works. EMBRIOLOGICAL BASIS & KDNEY : The abnormality originates between 4th and 6th weeks of gestation , after the ureteral bud has entered the renal blastema. Boyden (1931 postulated that at the 14mm stage (4.5 weeks the developing metanephric masses lie close to one another , any disturbance in their relationship may result in joining at their inferior poles. A slight alteration in the position of the umbilical or common iliac artery could change the orientation of migrating kidneys thus leading to contact and fusion. In 1941 Dees (Nation 1945 , Bell 1946 , Gleen 1959 , Campbell 1970 described horse - shoe kidney di sease occurrence in 0.25% of the population or about 1 in 400. OBSERVATION : In the present study 176 specimens of kidneys were studied out of which 40 were fetal specimens and the rest were adult specimens consisting of both cadaveric and sonograms. The ad ult specimens from cadavers were 76 and 60 from sonograms. MATERIAL & METHODS : Abdomen is opened ; superficial viscera and

  6. Physics and Applications of NIS Junctions

    Energy Technology Data Exchange (ETDEWEB)

    Ullom, J N

    2001-08-24

    This paper reviews the physics and applications of Normal-Insulator-Superconductor (NIS) tunnel junctions. The current-voltage properties of NIS junctions are diode-like with a strong temperature dependence. Hence, these structures can be used as sensitive thermometers at temperatures well below the energy gap, {Delta}, of the superconducting electrode. For junction voltages comparable to {Delta}/q, current flow removes energy from the normal electrode. This property has been exploited to build refrigerators capable of cooling thin-film circuits from 0.3 K to 0.1 K. Calorimeters and bolometers for the detection of X-rays and millimeter-wave radiation, respectively, have successfully been built from NIS junctions. NIS junctions have also been used to probe the superconducting state. Finally, recent ideas for the use of NIS junctions as simple circuit elements are described.

  7. Algorithms for Junctions in Directed Acyclic Graphs

    CERN Document Server

    Ferreira, Carlos Eduardo

    2012-01-01

    Given a pair of distinct vertices u, v in a graph G, we say that s is a junction of u, v if there are in G internally vertex disjoint directed paths from s to u and from s to v. We show how to characterize junctions in directed acyclic graphs. We also consider the two problems in the following and derive efficient algorithms to solve them. Given a directed acyclic graph G and a vertex s in G, how can we find all pairs of vertices of G such that s is a junction of them? And given a directed acyclic graph G and k pairs of vertices of G, how can we preprocess G such that all junctions of k given pairs of vertices could be listed quickly? All junctions of k pairs problem arises in an application in Anthropology and we apply our algorithm to find such junctions on kinship networks of some brazilian indian ethnic groups.

  8. Comparison of magnetic resonance urography with ultrasound studies in detection of fetal urogenital anomalies.

    Science.gov (United States)

    Kajbafzadeh, Abdol-Mohammad; Payabvash, Seyedmehdi; Sadeghi, Zhina; Elmi, Azadeh; Jamal, Ashraf; Hantoshzadeh, Zohreh; Eslami, Laleh; Mehdizadeh, Mehrzad

    2008-02-01

    Prenatal ultrasonography detects the vast majority of urogenital anomalies, but in some cases the diagnosis remains in doubt. We assessed the potential of magnetic resonance urography (MRU) in the evaluation of different urogenital anomalies in fetuses when ultrasound study was equivocal. We retrospectively reviewed the medical records of 46 fetuses in whom the presence of urogenital anomalies was suspected at ultrasound studies, but remained inconclusive. Fetal MRU was performed within the same week as ultrasound studies. All patients underwent MRU, comprising overview, fast, thick-slab, heavily T2-weighted sequences, followed by focused, high-resolution T2-weighted sequences obtained in sagittal, axial and coronal planes. T1-weighted sequences were obtained in selected cases for assessment of the gastrointestinal tract. All MRU results were compared with ultrasound findings. Sensitivity of each imaging modality was estimated based on definite diagnoses made after birth or abortion. The mean (range) gestational age was 27 (18-36)weeks. The final diagnosis was ureteropelvic junction obstruction in 12, ureteral dilation (due to vesicoureteral junction obstruction) in five, ureterocele in five, posterior urethral valve in 16, multicystic dysplastic kidney in six, mesenteric cyst in one and abdominoscrotal hydrocele in one. Overall diagnostic sensitivity of fetal MRU was 96% compared to sonography with 58% sensitivity (pMRU studies provided additional information to sonography in 17 (37%) cases, and were especially more sensitive in evaluation of ureteral anatomy. Fetal MRU can accurately diagnose a wide variety of urinary tract disorders and must be regarded as a valuable complementary tool to ultrasound in the assessment of the urinary system, particularly in cases of inconclusive ultrasound findings. The present study had a selection bias, as only fetuses with possible anomalies proposed by sonography were referred for MRU; however, this is the population that

  9. Fetal extracardiac anomalies associated with congenital cardiac diseases

    Energy Technology Data Exchange (ETDEWEB)

    Yi, Bum Ha; Cho, Jung Yeon; Lee, Young Ho; Song, Mi Jin [Samsung Cheil Hospital, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

    2004-06-15

    To evaluate the incidence of associated extracardiac anomalies in fetuses with congenital heart defects on fetal echocardiography, and to estimate the incidence of chromosomal abnormalities according to the extracardiac anomalies. From Jan. 1999 to Dec. 2001, 101 fetuses with prenatally diagnosed extracardiac anomalies and congenital cardiac diseases were selected for study. The mean gestational age at the time of the ultrasound exam was about 25 weeks. Associated extracardiac anomalies were classified into CNS, face and neck, thorax, abdomen, genitourinary system, musculoskeletal, other and multi-systemic anomalies groups. Chromosomal studies including chorionic villi sampling, amniocentesis, cordocentesis, and postnatal exam were correlated. Musculoskeletal anomalies were the most commonly associated extracardiac anomalies (n=28, 27.7%). Abdominal anomaly (n=26, 25.7%), central nervous system anomaly (n=25, 24.8%), genitourinary anomaly(n=12, 11.9%), thoracic anomaly (n=4, 4%), face and neck anomaly (n=3, 3%) were found. Twenty eight fetuses showed other anomalies (n=28, 27.7%). Multi-systemic anomalies were also common (n=20, 19.8%). Fetal anomalies involving two systems were noted in 15 fetuses, and anomalies of more than three systems were not uncommon (5 fetuses). Chromosomal study of 38 fetuses revealed 19 fetuses with abnormal karyotypes (50%). For 19 fetuses with abnormal karyotypes, central nervous system anomalies and musculoskeletal anomalies were the most frequently associated with extracardiac abnormalities (n=9). Multi-systemic anomalies were associated in 9 of the 19 fetuses. In fetuses with cardiac defects, the musculoskeletal, abdomen and CNS anomalies were commonly associated with extracardiac anomalies. Various extracardiac anomalies such as, head and neck anomalies, CNS anomalies, musculoskeletal anomalies, and multi-organ anomalies were highly correlated with chromosomal abnormalities, and so this relationship requires chromosomal study.

  10. Anomaly Detection in Dynamic Networks

    Energy Technology Data Exchange (ETDEWEB)

    Turcotte, Melissa [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2014-10-14

    Anomaly detection in dynamic communication networks has many important security applications. These networks can be extremely large and so detecting any changes in their structure can be computationally challenging; hence, computationally fast, parallelisable methods for monitoring the network are paramount. For this reason the methods presented here use independent node and edge based models to detect locally anomalous substructures within communication networks. As a first stage, the aim is to detect changes in the data streams arising from node or edge communications. Throughout the thesis simple, conjugate Bayesian models for counting processes are used to model these data streams. A second stage of analysis can then be performed on a much reduced subset of the network comprising nodes and edges which have been identified as potentially anomalous in the first stage. The first method assumes communications in a network arise from an inhomogeneous Poisson process with piecewise constant intensity. Anomaly detection is then treated as a changepoint problem on the intensities. The changepoint model is extended to incorporate seasonal behavior inherent in communication networks. This seasonal behavior is also viewed as a changepoint problem acting on a piecewise constant Poisson process. In a static time frame, inference is made on this extended model via a Gibbs sampling strategy. In a sequential time frame, where the data arrive as a stream, a novel, fast Sequential Monte Carlo (SMC) algorithm is introduced to sample from the sequence of posterior distributions of the change points over time. A second method is considered for monitoring communications in a large scale computer network. The usage patterns in these types of networks are very bursty in nature and don’t fit a Poisson process model. For tractable inference, discrete time models are considered, where the data are aggregated into discrete time periods and probability models are fitted to the

  11. Molecular junctions: can pulling influence optical controllability?

    Science.gov (United States)

    Parker, Shane M; Smeu, Manuel; Franco, Ignacio; Ratner, Mark A; Seideman, Tamar

    2014-08-13

    We suggest the combination of single molecule pulling and optical control as a way to enhance control over the electron transport characteristics of a molecular junction. We demonstrate using a model junction consisting of biphenyl-dithiol coupled to gold contacts. The junction is pulled while optically manipulating the dihedral angle between the two rings. Quantum dynamics simulations show that molecular pulling enhances the degree of control over the dihedral angle and hence over the transport properties.

  12. Loss models for long Josephson junctions

    DEFF Research Database (Denmark)

    Olsen, O. H.; Samuelsen, Mogens Rugholm

    1984-01-01

    A general model for loss mechanisms in long Josephson junctions is presented. An expression for the zero-field step is found for a junction of overlap type by means of a perturbation method. Comparison between analytic solution and perturbation result shows good agreement.......A general model for loss mechanisms in long Josephson junctions is presented. An expression for the zero-field step is found for a junction of overlap type by means of a perturbation method. Comparison between analytic solution and perturbation result shows good agreement....

  13. Vitellointestinal Duct Anomalies in Infancy

    Science.gov (United States)

    Kadian, Yogender Singh; Verma, Anjali; Rattan, Kamal Nain; Kajal, Pardeep

    2016-01-01

    Background: Vitellointestinal duct (VID) or omphalomesenteric duct anomalies are secondary to the persistence of the embryonic vitelline duct, which normally obliterates by weeks 5–9 of intrauterine life. Methods: This is a retrospective analysis of a total of 16 patients of symptomatic remnants of vitellointestinal duct from period of Jan 2009 to May 2013. Results: Male to female ratio (M:F) was 4.3:1 and mean age of presentation was 2 months and their mode of presentation was: patent VID in 9 (56.25%) patients, umbilical cyst in 2(12.25%), umbilical granuloma in 2 (12.25%), and Meckel diverticulum as content of hernia sac in obstructed umbilical hernia in 1 (6.25%) patient. Two patients with umbilical fistula had severe electrolyte disturbance and died without surgical intervention. Conclusion: Persistent VID may have varied presentations in infancy. High output umbilical fistula and excessive bowel prolapse demand urgent surgical intervention to avoid morbidity and mortality. PMID:27433448

  14. Holography and Conformal Anomaly Matching

    CERN Document Server

    Cabo-Bizet, Alejandro; Narain, K S

    2013-01-01

    We discuss various issues related to the understanding of the conformal anomaly matching in CFT from the dual holographic viewpoint. First, we act with a PBH diffeomorphism on a generic 5D RG flow geometry and show that the corresponding on-shell bulk action reproduces the Wess-Zumino term for the dilaton of broken conformal symmetry, with the expected coefficient aUV-aIR. Then we consider a specific 3D example of RG flow whose UV asymptotics is normalizable and admits a 6D lifting. We promote a modulus \\rho appearing in the geometry to a function of boundary coordinates. In a 6D description {\\rho} is the scale of an SU(2) instanton. We determine the smooth deformed background up to second order in the space-time derivatives of \\rho and find that the 3D on-shell action reproduces a boundary kinetic term for the massless field \\tau= log(\\rho) with the correct coefficient \\delta c=cUV-cIR. We further analyze the linearized fluctuations around the deformed background geometry and compute the one-point functions ...

  15. Data Mining for Anomaly Detection

    Science.gov (United States)

    Biswas, Gautam; Mack, Daniel; Mylaraswamy, Dinkar; Bharadwaj, Raj

    2013-01-01

    The Vehicle Integrated Prognostics Reasoner (VIPR) program describes methods for enhanced diagnostics as well as a prognostic extension to current state of art Aircraft Diagnostic and Maintenance System (ADMS). VIPR introduced a new anomaly detection function for discovering previously undetected and undocumented situations, where there are clear deviations from nominal behavior. Once a baseline (nominal model of operations) is established, the detection and analysis is split between on-aircraft outlier generation and off-aircraft expert analysis to characterize and classify events that may not have been anticipated by individual system providers. Offline expert analysis is supported by data curation and data mining algorithms that can be applied in the contexts of supervised learning methods and unsupervised learning. In this report, we discuss efficient methods to implement the Kolmogorov complexity measure using compression algorithms, and run a systematic empirical analysis to determine the best compression measure. Our experiments established that the combination of the DZIP compression algorithm and CiDM distance measure provides the best results for capturing relevant properties of time series data encountered in aircraft operations. This combination was used as the basis for developing an unsupervised learning algorithm to define "nominal" flight segments using historical flight segments.

  16. Thermal infrared anomalies of several strong earthquakes.

    Science.gov (United States)

    Wei, Congxin; Zhang, Yuansheng; Guo, Xiao; Hui, Shaoxing; Qin, Manzhong; Zhang, Ying

    2013-01-01

    In the history of earthquake thermal infrared research, it is undeniable that before and after strong earthquakes there are significant thermal infrared anomalies which have been interpreted as preseismic precursor in earthquake prediction and forecasting. In this paper, we studied the characteristics of thermal radiation observed before and after the 8 great earthquakes with magnitude up to Ms7.0 by using the satellite infrared remote sensing information. We used new types of data and method to extract the useful anomaly information. Based on the analyses of 8 earthquakes, we got the results as follows. (1) There are significant thermal radiation anomalies before and after earthquakes for all cases. The overall performance of anomalies includes two main stages: expanding first and narrowing later. We easily extracted and identified such seismic anomalies by method of "time-frequency relative power spectrum." (2) There exist evident and different characteristic periods and magnitudes of thermal abnormal radiation for each case. (3) Thermal radiation anomalies are closely related to the geological structure. (4) Thermal radiation has obvious characteristics in abnormal duration, range, and morphology. In summary, we should be sure that earthquake thermal infrared anomalies as useful earthquake precursor can be used in earthquake prediction and forecasting.

  17. MR imaging of paediatric uterovaginal anomalies

    Energy Technology Data Exchange (ETDEWEB)

    Lang, I.M.; Babyn, P. [Hospital for Sick Children, Toronto, ON (Canada). Dept. of Diagnostic Imaging; Oliver, G.D. [Hospital for Sick Children, Toronto, ON (Canada). Dept. of Gynaecology

    1999-03-01

    Background. Transabdominal ultrasound (US) has not proved completely reliable in Muellerian duct anomalies. One study has shown it useful in obstructed uterovaginal anomalies. We are unaware of a study that has used endovaginal ultrasound in children to investigate uterovaginal anomalies. Magnetic resonance imaging (MRI) is now gaining wide acceptance in imaging congenital abnormalities of the genital tract. Objective. To identify the problems and potential pitfalls of using MRI to evaluate the female genital tract in paediatric patients. Materials and methods. A retrospective review of the MRI scans of 19 patients, aged 3 months to 19 years (mean 14 years), with uterovaginal anomalies. Results. The uterovaginal anomalies were categorised into three groups: (1) congenital absence of the Muellerian ducts, or the Mayer-Rokitansky-Kuster-Hauser syndrome (n = 7), (2) disorders of vertical fusion (n = 2) and (3) disorders of lateral fusion (n = 10). Conclusions. MRI is a reliable method for evaluating paediatric uterovaginal anomalies, but should be analysed in conjunction with other imaging modalities (US and genitography). Previous surgery makes interpretation more difficult and, if possible, MRI should be carried out prior to any surgery. An accurate MRI examination can be extremely helpful prior to surgery and it is important for the radiologist to have knowledge of how these complex anomalies are managed and what pitfalls to avoid. (orig.) With 7 figs., 4 tabs., 24 refs.

  18. Galilean Anomalies and Their Effect on Hydrodynamics

    CERN Document Server

    Jain, Akash

    2015-01-01

    We extend the null background construction of [arXiv:1505.05677,arXiv:1509.04718] to include torsion and a conserved spin current, and use it to study gauge and gravitational anomalies in Galilean theories coupled to torsional Newton-Cartan backgrounds. We establish that the relativistic anomaly inflow mechanism with an appropriately modified anomaly polynomial, can be used to generate these anomalies. Similar to relativistic case, we find that Galilean anomalies also survive only in even dimensions. Further, these anomalies only effect the gauge and rotational symmetries of a Galilean theory; in particular the Milne boost symmetry remains non-anomalous. We also extend the transgression machinery used in relativistic fluids to fluids on null backgrounds, and use it to determine how these anomalies affect the constitutive relations of a Galilean fluid. Unrelated to Galilean fluids, we propose an analogue of the off-shell second law of thermodynamics for relativistic fluids introduced by [arXiv:1106.0277], to i...

  19. Sea surface temperature anomalies in the Arabian Sea

    Digital Repository Service at National Institute of Oceanography (India)

    RameshKumar, M.R.

    . Further analysis has shown that the sea surface anomalies are well correlated to the anomalies of air temperature and latent heat flux values; whereas they are least correlated to the anomalies of wind stress and net radiation values, except over...

  20. Praenatalt diagnosticeret hydronefrose og andre urologiske anomalier

    DEFF Research Database (Denmark)

    Cortes, Dina; Jørgensen, Troels Munch; Rittig, Søren

    2006-01-01

    By renal ultrasound examination, urological anomalies may be demonstrated in 1-2% of fetuses and in about 0.5% of newborns. Boys have about twice the frequency of girls. Surgical treatment is indicated in about one fourth of these urological anomalies. If all pregnant women in Denmark were to have...... fetal ultrasound examination of the kidneys and the urinary tract, about 70 children would be born each year with a prenatally diagnosed urological anomaly for which surgical procedure is or will be indicated. This paper provides Danish guidelines for prenatal diagnosis, follow-up and intervention...

  1. Anomaly and exotic statistics in one dimension

    CERN Document Server

    Saradzhev, F M

    1995-01-01

    We study the influence of the anomaly on the physical quantum picture of the chiral Schwinger model (CSM) defined on S^1. We show that such phenomena as the total screening of charges and the dynamical mass generation characteristic for the standard Schwinger model do not take place here. Instead of them, the anomaly results in the background linearly rising electric field or, equivalently, in the exotic statistics of the physical matter field. We construct the algebra of the Poincare generators and show that it differs from the Poincare one. For the CSM on R^1, the anomaly influences only the mass generation mechanism.

  2. Simple recipe for holographic Weyl anomaly

    CERN Document Server

    Bugini, F

    2016-01-01

    We propose a recipe - arguably the simplest - to compute the holographic type-B Weyl anomaly for general higher-derivative gravity in asymptotically AdS spacetimes. In 5 and 7 dimensions we identify a suitable basis of curvature invariants that allows to read off easily, without any further computation, the Weyl anomaly coefficients of the dual CFT. We tabulate the contributions from quadratic, cubic and quartic purely algebraic curvature invariants and also from terms involving derivatives of the curvature. We provide few examples, where the anomaly coefficients have been obtained by other means, to illustrate the effectiveness of our prescription.

  3. Considerations in the Interpretation of Cosmological Anomalies

    CERN Document Server

    Peiris, Hiranya V

    2014-01-01

    Anomalies drive scientific discovery -- they are associated with the cutting edge of the research frontier, and thus typically exploit data in the low signal-to-noise regime. In astronomy, the prevalence of systematics --- both "known unknowns" and "unknown unknowns" --- combined with increasingly large datasets, the widespread use of ad hoc estimators for anomaly detection, and the "look-elsewhere" effect, can lead to spurious false detections. In this informal note, I argue that anomaly detection leading to discoveries of new physics requires a combination of physical understanding, careful experimental design to avoid confirmation bias, and self-consistent statistical methods. These points are illustrated with several concrete examples from cosmology.

  4. Gravitational anomalies in higher dimensional Riemann Cartan space

    Science.gov (United States)

    Yajima, S.; Tokuo, S.; Fukuda, M.; Higashida, Y.; Kamo, Y.; Kubota, S.-I.; Taira, H.

    2007-02-01

    By applying the covariant Taylor expansion method of the heat kernel, the covariant Einstein anomalies associated with a Weyl fermion of spin \\frac{1}{2} in four-, six- and eight-dimensional Riemann Cartan space are manifestly given. Many unknown terms with torsion tensors appear in these anomalies. The Lorentz anomaly is intimately related to the Einstein anomaly even in Riemann Cartan space. The explicit form of the Lorentz anomaly corresponding to the Einstein anomaly is also obtained.

  5. Gravitational anomalies in higher dimensional Riemann-Cartan space

    Energy Technology Data Exchange (ETDEWEB)

    Yajima, S [Department of Physics, Kumamoto University, 2-39-1 Kurokami, Kumamoto 860-8555 (Japan); Tokuo, S [Department of Physics, Kumamoto University, 2-39-1 Kurokami, Kumamoto 860-8555 (Japan); Fukuda, M [Department of Physics, Kumamoto University, 2-39-1 Kurokami, Kumamoto 860-8555 (Japan); Higashida, Y [Takuma National College of Technology, 551 kohda, Takuma-cho, Mitoyo, Kagawa 769-1192 (Japan); Kamo, Y [Radioisotope Center, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582 (Japan); Kubota, S-I [Computing and Communications Center, Kagoshima University, 1-21-35 Koorimoto, Kagoshima 890-0065 (Japan); Taira, H [Department of Physics, Kumamoto University, 2-39-1 Kurokami, Kumamoto 860-8555 (Japan)

    2007-02-21

    By applying the covariant Taylor expansion method of the heat kernel, the covariant Einstein anomalies associated with a Weyl fermion of spin 1/2 in four-, six- and eight-dimensional Riemann-Cartan space are manifestly given. Many unknown terms with torsion tensors appear in these anomalies. The Lorentz anomaly is intimately related to the Einstein anomaly even in Riemann-Cartan space. The explicit form of the Lorentz anomaly corresponding to the Einstein anomaly is also obtained.

  6. Using EVT for Geological Anomaly Design and Its Application in Identifying Anomalies in Mining Areas

    Directory of Open Access Journals (Sweden)

    Feilong Qin

    2016-01-01

    Full Text Available A geological anomaly is the basis of mineral deposit prediction. Through the study of the knowledge and characteristics of geological anomalies, the category of extreme value theory (EVT to which a geological anomaly belongs can be determined. Associating the principle of the EVT and ensuring the methods of the shape parameter and scale parameter for the generalized Pareto distribution (GPD, the methods to select the threshold of the GPD can be studied. This paper designs a new algorithm called the EVT model of geological anomaly. These study data on Cu and Au originate from 26 exploration lines of the Jiguanzui Cu-Au mining area in Hubei, China. The proposed EVT model of the geological anomaly is applied to identify anomalies in the Jiguanzui Cu-Au mining area. The results show that the model can effectively identify the geological anomaly region of Cu and Au. The anomaly region of Cu and Au is consistent with the range of ore bodies of actual engineering exploration. Therefore, the EVT model of the geological anomaly can effectively identify anomalies, and it has a high indicating function with respect to ore prospecting.

  7. Direct lateral interbody fusion (DLIF) at the lumbosacral junction L5-S1.

    Science.gov (United States)

    Shirzadi, Ali; Birch, Kurtis; Drazin, Doniel; Liu, John C; Acosta, Frank

    2012-07-01

    The direct lateral interbody fusion (DLIF), a minimally invasive lateral approach for placement of an interbody fusion device, does not require nerve root retraction or any contact with the great vessels and can lead to short operative times with little blood loss. Due to anatomical restrictions, this procedure has not been used at the lumbosacral (L5-S1) junction. Lumbosacral transitional vertebrae (LSTV), a structural anomaly of the lumbosacral spine associated with low back pain, can result in a level being wrongly identified pre-operatively due to misnumbering of the vertebral levels. To our knowledge, use of the DLIF graft in this patient is the first report of an interbody fusion graft being placed at the disc space between the LSTV and S1 via the transpsoas route. We present a review of the literature regarding the LSTV variation as well as the lateral placement of interbody fusion grafts at the lumbosacral junction.

  8. Universal transport signatures of Majorana fermions in superconductor-Luttinger liquid junctions

    Science.gov (United States)

    Fidkowski, Lukasz; Alicea, Jason; Lindner, Netanel H.; Lutchyn, Roman M.; Fisher, Matthew P. A.

    2012-06-01

    One of the most promising proposals for engineering topological superconductivity and Majorana fermions employs a spin-orbit coupled nanowire subjected to a magnetic field and proximate to an s-wave superconductor. When only part of the wire's length contacts to the superconductor, the remaining conducting portion serves as a natural lead that can be used to probe these Majorana modes via tunneling. The enhanced role of interactions in one dimension dictates that this configuration should be viewed as a superconductor-Luttinger liquid junction. We investigate such junctions between both helical and spinful Luttinger liquids, and topological as well as nontopological superconductors. We determine the phase diagram for each case and show that universal low-energy transport in these systems is governed by fixed points describing either perfect normal reflection or perfect Andreev reflection. In addition to capturing (in some instances) the familiar Majorana-mediated “zero-bias anomaly” in a new framework, we show that interactions yield dramatic consequences in certain regimes. Indeed, we establish that strong repulsion removes this conductance anomaly altogether while strong attraction produces dynamically generated effective Majorana modes even in a junction with a trivial superconductor. Interactions further lead to striking signatures in the local density of states and the line shape of the conductance peak at finite voltage, and also are essential for establishing smoking-gun transport signatures of Majorana fermions in spinful Luttinger liquid junctions.

  9. Gap junctions and connexin-interacting proteins

    NARCIS (Netherlands)

    Giepmans, Ben N G

    2004-01-01

    Gap junctions form channels between adjacent cells. The core proteins of these channels are the connexins. Regulation of gap junction communication (GJC) can be modulated by connexin-associating proteins, such as regulatory protein phosphatases and protein kinases, of which c-Src is the best-studied

  10. Gap junctions and connexin-interacting proteins

    NARCIS (Netherlands)

    Giepmans, Ben N G

    2004-01-01

    Gap junctions form channels between adjacent cells. The core proteins of these channels are the connexins. Regulation of gap junction communication (GJC) can be modulated by connexin-associating proteins, such as regulatory protein phosphatases and protein kinases, of which c-Src is the

  11. Gap junctions and connexin-interacting proteins

    NARCIS (Netherlands)

    Giepmans, Ben N G

    2004-01-01

    Gap junctions form channels between adjacent cells. The core proteins of these channels are the connexins. Regulation of gap junction communication (GJC) can be modulated by connexin-associating proteins, such as regulatory protein phosphatases and protein kinases, of which c-Src is the best-studied

  12. Shot noise in YBCO bicrystal Josephson junctions

    DEFF Research Database (Denmark)

    Constantinian, K.Y.; Ovsyannikov, G.A.; Borisenko, I.V.;

    2003-01-01

    We measured spectral noise density in YBCO symmetric bicrystal Josephson junctions on sapphire substrates at bias voltages up to 100 mV and T 4.2 K. Normal state resistance of the Josephson junctions, R-N = 20-90 Omega and ICRN up to 2.2 mV have been observed in the experimental samples. Noise...

  13. Comparison of Unsupervised Anomaly Detection Methods

    Data.gov (United States)

    National Aeronautics and Space Administration — Several different unsupervised anomaly detection algorithms have been applied to Space Shuttle Main Engine (SSME) data to serve the purpose of developing a...

  14. Magnetic anomalies in Central Bengal fan

    Digital Repository Service at National Institute of Oceanography (India)

    Rao, T.C.S.; Lakshminarayana, S.; Sarma, K.V.L.N.S.

    Total magnetic field anomalies recorded over the Central Bengal Fan are analysed and the depths to the magnetic basement are computed using the analytical signal and the Werner deconvolution methods. To the west and east of 85 degrees E...

  15. Ionospheric Anomaly before Kyushu|Japan Earthquake

    Directory of Open Access Journals (Sweden)

    YANG Li

    2017-05-01

    Full Text Available GIM data released by IGS is used in the article and a new method of combining the Sliding Time Window Method and the Ionospheric TEC correlation analysis method of adjacent grid points is proposed to study the relationship between pre-earthquake ionospheric anomalies and earthquake. By analyzing the abnormal change of TEC in the 5 grid points around the seismic region, the abnormal change of ionospheric TEC is found before the earthquake and the correlation between the TEC sequences of lattice points is significantly affected by earthquake. Based on the analysis of the spatial distribution of TEC anomaly, anomalies of 6 h, 12 h and 6 h were found near the epicenter three days before the earthquake. Finally, ionospheric tomographic technology is used to do tomographic inversion on electron density. And the distribution of the electron density in the ionospheric anomaly is further analyzed.

  16. SEG US Bouguer Gravity Anomaly Grid

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The SEG gravity data are the product of the ad hoc Gravity Anomaly Map (GAM) Committee, sponsored by the Society of Exploration Geophysicists (SEG) and the U.S....

  17. Mexico Terrain Corrected Free Air Anomalies (97)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This 2' gravity anomaly grid for Mexico, North-Central America and the Western Caribbean Sea is NOT the input data set used in the development of the MEXICO97 model....

  18. Design and Implementation of an Anomaly Detector

    Energy Technology Data Exchange (ETDEWEB)

    Bagherjeiran, A; Cantu-Paz, E; Kamath, C

    2005-07-11

    This paper describes the design and implementation of a general-purpose anomaly detector for streaming data. Based on a survey of similar work from the literature, a basic anomaly detector builds a model on normal data, compares this model to incoming data, and uses a threshold to determine when the incoming data represent an anomaly. Models compactly represent the data but still allow for effective comparison. Comparison methods determine the distance between two models of data or the distance between a model and a point. Threshold selection is a largely neglected problem in the literature, but the current implementation includes two methods to estimate thresholds from normal data. With these components, a user can construct a variety of anomaly detection schemes. The implementation contains several methods from the literature. Three separate experiments tested the performance of the components on two well-known and one completely artificial dataset. The results indicate that the implementation works and can reproduce results from previous experiments.

  19. Major congenital anomalies in a Danish region

    DEFF Research Database (Denmark)

    Garne, Ester; Hansen, Anne Vinkel; Birkelund, Anne Sofie;

    2014-01-01

    : diabetes, epilepsy, mental disorder, thyroid disease, asthma, or inflammatory bowel disease. Medication for these conditions accounted for 46% of maternal drug use. CONCLUSION: Maternal morbidity and use of potentially teratogenic medication have increased among congenital anomaly cases. Foetal and infant...

  20. Isostatic geoid anomalies on a sphere

    Science.gov (United States)

    Dahlen, F. A.

    1982-01-01

    Long-wavelength geoid anomalies due to lateral variations in the density or thickness of a thin layer in local isostatic equilibrium on the surface of a sphere depend sensitively on the assumed state of stress within the layer. A number of common intuitive definitions of local isostasy generally believed to be essentially identical are associated with quite different states of isostatic stress, and the corresponding theoretical geoid anomalies can vary by more than a factor of 2. This sensitivity of the theoretical anomaly to the exact definition of local isostasy constitutes an obstacle to any proposed program of interpreting or exploiting observed global isostatic geoid anomalies such as those associated with the aging of the oceanic lithosphere.

  1. Coral Reef Watch, Temperature Anomaly, 50 km

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Coral Reef Watch distributes SST anomaly data using a combination of the POES AVHRR Global Area Coverage data, and data from a climatological database. AVHRR...

  2. Congenital microgastria and hypoplastic upper limb anomalies.

    Science.gov (United States)

    Lueder, G T; Fitz-James, A; Dowton, S B

    1989-03-01

    Six cases of congenital microgastria associated with limb anomalies are reviewed. The microgastria-hypoplastic upper limb association may arise as a result of aberrant mesodermal development in the 5th embryonic week.

  3. Viscosity anomaly in core-softened liquids

    OpenAIRE

    Fomin, Yu. D.; Ryzhov, V. N.

    2013-01-01

    The present article presents a molecular dynamics study of several anomalies of core-softened systems. It is well known that many core-softened liquids demonstrate diffusion anomaly. Usual intuition relates the diffusion coefficient to shear viscosity via Stockes-Einstein relation. However, it can break down at low temperature. In this respect it is important to see if viscosity also demonstrates anomalous behavior.

  4. Mullerian anomalies: a cause of primary amenorrhea

    OpenAIRE

    2013-01-01

    Background: The objectives of this study were to determine the etiologic causes of amenorrhea, the prevalence of mullerian anomalies as a cause of primary amenorrhea and the different varieties of mullerian anomalies causing primary amenorrhea. Methods: This study included all the women presenting with primary amenorrhea who presented to the department of obstetrics and gynecology, Sir T Hospital and Government Medical College, Bhavnagar from 1st January 2010 to 30th June 2012. Results: The c...

  5. Efficient Accurate Context-Sensitive Anomaly Detection

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    For program behavior-based anomaly detection, the only way to ensure accurate monitoring is to construct an efficient and precise program behavior model. A new program behavior-based anomaly detection model,called combined pushdown automaton (CPDA) model was proposed, which is based on static binary executable analysis. The CPDA model incorporates the optimized call stack walk and code instrumentation technique to gain complete context information. Thereby the proposed method can detect more attacks, while retaining good performance.

  6. Lateral sacral lipomyelomeningocele : a rare anomaly.

    Directory of Open Access Journals (Sweden)

    Shetty D

    2002-04-01

    Full Text Available Lateral sacral lipomyelomeningocele is a rare spinal developmental anomaly. In the case under report, the fat attached to the neural placode was blending with the gluteal fat externally. The cord was tethered at this level. Multiple bony anomalies and diastematomyelia were associated findings. A case of lateral sacral lipomyelomeningocele with excellent imaging detail provided by the multiplanar magnetic resonance (MR scan is reported.

  7. Gauge anomalies in Lorentz-violating QED

    Science.gov (United States)

    Santos, Tiago R. S.; Sobreiro, Rodrigo F.

    2016-12-01

    In this work we study the issue of gauge anomalies in Lorentz-violating QED. To do so, we opt to use the Becchi-Rouet-Stora-Tyutin formalism within the algebraic renormalization approach, reducing our study to a cohomology problem. Since this approach is independent of the renormalization scheme, the results obtained here are expected to be general. We find that the Lorentz-violating QED is free of gauge anomalies to all orders in perturbation theory.

  8. Gauge anomalies in Lorentz-violating QED

    CERN Document Server

    Santos, Tiago R S

    2016-01-01

    In this work we study the issue of gauge anomalies in Lorentz-violating QED. To do so, we opt to use the BRST formalism within of the algebraic renormalization approach, reducing our study to a cohomology problem. Since that this approach is independent of the renormalization scheme, the results here obtained are expected to be general. We find that the Lorentz-violating QED is free of gauge anomalies to all orders in perturbation theory.

  9. Craniofacial anomalies: from development to molecular pathogenesis.

    Science.gov (United States)

    Rice, David P C

    2005-11-01

    Advances in developmental biology combined with progress in human genetics are helping us decipher how the craniofacial region develops and how the consequences of misdirected development result in malformation. This review describes the molecular etiology of a number of craniofacial developmental anomalies. The more common craniofacial anomalies cleft lip and palate and craniosynostosis, as well as cleidocranial dysplasia, hemifacial microsomia, holoprosencephaly, enlarged parietal foramina, Treacher Collins syndrome and cherubism are discussed.

  10. CP-violating CFT and trace anomaly

    CERN Document Server

    Nakayama, Yu

    2012-01-01

    It is logically possible that the trace anomaly in four dimension includes the Hirzebruch-Pontryagin density in CP violating theories. Although the term vanishes at free conformal fixed points, we realize such a possibility in the holographic renormalization group and show that it is indeed possible. The Hirzebruch-Pontryagin term in the trace anomaly may serve as a barometer to understand how much CP is violated in conformal field theories.

  11. Reports on various anomalies of the ribs

    Energy Technology Data Exchange (ETDEWEB)

    Brinkmann, G.; Brix, F.

    1988-02-01

    Three patients are presented who were suffering from different anomalies of the ribs: There was one each plus and minus variant and a female patient with Gorlin-Goltz syndrome (basal cell nevus syndrome) demonstrating several changes in the ribs as an expression of a genetically determined segmentation disturbance. These presentations are followed by a detailed discussion on the types and causes of such anomalies.

  12. Anomalous transport due to scale anomaly

    CERN Document Server

    Chernodub, M N

    2016-01-01

    We show that the scale anomaly in field theories leads to new anomalous transport effects that emerge in external electromagnetic field in inhomogeneous gravitational background. In inflating geometry the QED scale anomaly generates electric current which flows in opposite direction with respect to background electric field. In static spatially inhomogeneous gravitational background the dissipationless electric current flows transversely both to the magnetic field axis and to the gradient of the inhomogeneity. The anomalous currents are proportional to the beta function of the theory.

  13. On the topological interpretation of gravitational anomalies

    Science.gov (United States)

    Perrot, Denis

    2001-07-01

    We consider the mixed gravitational Yang-Mills anomaly as the coupling between the K-theory and K-homology of a C ∗-algebra crossed product. The index theorem of Connes-Moscovici allows to compute the Chern character of the K-cycle by local formulae involving connections and curvatures. It gives a topological interpretation to the anomaly, in the sense of noncommutative algebras.

  14. Shear zone junctions: Of zippers and freeways

    Science.gov (United States)

    Passchier, Cees W.; Platt, John P.

    2017-02-01

    Ductile shear zones are commonly treated as straight high-strain domains with uniform shear sense and characteristic curved foliation trails, bounded by non-deforming wall rock. Many shear zones, however, are branched, and if movement on such branches is contemporaneous, the resulting shape can be complicated and lead to unusual shear sense arrangement and foliation geometries in the wall rock. For Y-shaped shear zone triple junctions with three joining branches and transport direction at a high angle to the branchline, only eight basic types of junction are thought to be stable and to produce significant displacement. The simplest type, called freeway junctions, have similar shear sense in all three branches. The other types show joining or separating behaviour of shear zone branches similar to the action of a zipper. Such junctions may have shear zone branches that join to form a single branch (closing zipper junction), or a single shear zone that splits to form two branches, (opening zipper junction). All categories of shear zone junctions show characteristic foliation patterns and deflection of markers in the wall rock. Closing zipper junctions are unusual, since they form a non-active zone with opposite deflection of foliations in the wall rock known as an extraction fault or wake. Shear zipper junctions can form domains of overprinting shear sense along their flanks. A small and large field example are given from NE Spain and Eastern Anatolia. The geometry of more complex, 3D shear zone junctions with slip parallel and oblique to the branchline is briefly discussed.

  15. Medical imaging for congenital anomalies of the lung. Focused on tracheobronchial and parenchymal anomalies

    Energy Technology Data Exchange (ETDEWEB)

    Kohda, Ehiichi; Shiraga, Nobuyuki; Higuchi, Mutsumi; Ishibashi, Ryouchi [Tachikawa Hospital, Tokyo (Japan)

    2003-02-01

    This is a review of medical imaging studies for congenital anomalies of the lung focused on tracheobronchial and parenchymal anomalies. It is important to know the findings of these developmental anomalies, because they are frequently manifested as infectious diseases or mass. Documented details are pulmonary agenesis, aplasia, pulmonary hypoplasia, tracheal agenesis, bridging bronchus, tracheal bronchus, congenital tracheal stenosis, bronchial atresia, bronchobiliary fistula, bronchogenic cyst, bronchopulmonary sequestration, congenital cystic adenomatoid malformation, and pulmonary lymphangiectasia. (author)

  16. Junction conditions of cosmological perturbations

    CERN Document Server

    Tomita, K

    2004-01-01

    The behavior of perturbations is studied in cosmological models which consist of two different homogeneous regions connected in a spherical shell boundary. The junction conditions for the metric perturbations and the displacements of the shell boundary are analyzed and the surface densities of the perturbed energy and momentum in the shell are derived, using Mukohyama's gauge-invariant formalism and the Israel discontinuity condition. In both homogeneous regions the perturbations of scalar, vector and tensor types are expanded using the 3-dimensional harmonic functions, but the model coupling among them is caused in the shell by the inhomogeneity. By treating the perturbations with odd and even parities separately, it is found, however, that we can have consistent displacements and surface densities for given metric parturbations

  17. Clustering and Recurring Anomaly Identification: Recurring Anomaly Detection System (ReADS)

    Science.gov (United States)

    McIntosh, Dawn

    2006-01-01

    This viewgraph presentation reviews the Recurring Anomaly Detection System (ReADS). The Recurring Anomaly Detection System is a tool to analyze text reports, such as aviation reports and maintenance records: (1) Text clustering algorithms group large quantities of reports and documents; Reduces human error and fatigue (2) Identifies interconnected reports; Automates the discovery of possible recurring anomalies; (3) Provides a visualization of the clusters and recurring anomalies We have illustrated our techniques on data from Shuttle and ISS discrepancy reports, as well as ASRS data. ReADS has been integrated with a secure online search

  18. MAGSAT correlations with geoid anomalies. [magnetic anomalies in the western Gulf of Mexico

    Science.gov (United States)

    Bowin, C. O. (Principal Investigator)

    1984-01-01

    A digital data library of MAGSAT data is described and its applications and capabilities are reviewed. Polynomial trends were removed from each half-orbit in order to estimate and remove ring current effects from the data. The MAGSAT data in the Gulf of Mexico region was analyzed to define better the possible relation of the negative MAGSAT anomaly there to the negative residual geoid anomaly in the western Gulf of Mexico. Since the shape and location of the negative magnetic anomaly are variable depending upon the particular polynomial surface and curve orders used, no definitive conclusion as to the degree of correspondance between the residual geoid and MAGSAT lithosphere anomalies is offered.

  19. MR imaging of Asherman's syndrome in patients with and without uterine anomalies : comparison with hysterosalpingography

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jung Sik; Kim, Hong; Kim, Taek Hoon [Keimyung Univ., DongSan Medical Center , Seoul (Korea, Republic of)

    1999-03-01

    To assess the role of MR imaging in the detection of Asherman's syndrome, especially when this is associated with a congenital uterine anomaly. MR images were obtained in the semicoronal plane parallel to the long axis of the uterus in 11 patients. Dilatation and curettage involving the insertion of an intrauterine device was performed in all patients, and transabdominal metroplasty was performed in four with uterine anomaly. MR imaging findings were compared with those of hysterosalpingography in all patients and compared with surgical findings in four. The MR findings of uterine synechia demonstrated in nine of 11 patients were focal thickening of the uterine junctional zone (n=2), hypointense foci in the endometrium (n=1), or both these findings (n=6). Seven of the 11 patients had associated uterine anomalies, which were demonstrated in all seven by MR imaging. In four of the seven, HSG failed to demonstrate these anomalies. MR imaging satisfactorily demonstrated intrauterine lesions in nine of 11 patients with Asherman's syndrome, and was especially helpful in demonstrating associated uterine anomalies.

  20. Coordinate transformation in the model of long Josephson junctions: geometrically equivalent Josephson junctions

    Science.gov (United States)

    Semerdzhieva, E. G.; Boyadzhiev, T. L.; Shukrinov, Yu. M.

    2005-10-01

    The transition from the model of a long Josephson junction of variable width to the model of a junction with a coordinate-dependent Josephson current amplitude is effected through a coordinate transformation. This establishes the correspondence between the classes of Josephson junctions of variable width and quasi-one-dimensional junctions with a variable thickness of the barrier layer. It is shown that for a junction of exponentially varying width the barrier layer of the equivalent quasi-one-dimensional junction has a distributed resistive inhomogeneity that acts as an attractor for magnetic flux vortices. The curve of the critical current versus magnetic field for a Josephson junction with a resistive microinhomogeneity is constructed with the aid of a numerical simulation, and a comparison is made with the critical curve of a junction of exponentially varying width. The possibility of replacing a distributed inhomogeneity in a Josephson junction by a local inhomogeneity at the end of the junction is thereby demonstrated; this can have certain advantages from a technological point of view.

  1. Atomically Abrupt Topological p-n Junction.

    Science.gov (United States)

    Kim, Sung Hwan; Jin, Kyung-Hwan; Kho, Byung Woo; Park, Byeong-Gyu; Liu, Feng; Kim, Jun Sung; Yeom, Han Woong

    2017-08-24

    Topological insulators (TI's) are a new class of quantum matter with extraordinary surface electronic states, which bear great potential for spintronics and error-tolerant quantum computing. In order to put a TI into any practical use, these materials need to be fabricated into devices whose basic units are often p-n junctions. Interesting electronic properties of a 'topological' p-n junction were proposed theoretically such as the junction electronic state and the spin rectification. However, the fabrication of a lateral topological p-n junction has been challenging because of materials, process, and fundamental reasons. Here, we demonstrate an innovative approach to realize a p-n junction of topological surface states (TSS's) of a three-dimensional (3D) topological insulator (TI) with an atomically abrupt interface. When a ultrathin Sb film is grown on a 3D TI of Bi2Se3 with a typical n-type TSS, the surface develops a strongly p-type TSS through the substantial hybridization between the 2D Sb film and the Bi2Se3 surface. Thus, the Bi2Se3 surface covered partially with Sb films bifurcates into areas of n- and p-type TSS's as separated by atomic step edges with a lateral electronic junction of as short as 2 nm. This approach opens a different avenue toward various electronic and spintronic devices based on well-defined topological p-n junctions with the scalability down to atomic dimensions.

  2. Abdominal aortic surgery and renal anomalies

    Directory of Open Access Journals (Sweden)

    Ilić Nikola

    2011-01-01

    Full Text Available Introduction. Kidney anomalies present a challenge even for the most experienced vascular surgeon in the reconstruction of the aortoilliac segment. The most significant anomalies described in the surgery of the aortoilliac segment are a horse-shoe and ectopic kidney. Objective. The aim of this retrospective study was to analyze experience on 40 patients with renal anomalies, who underwent surgery of the aortoilliac segment and to determine attitudes on conventional surgical treatment. Methods. In the period from 1992 to 2009, at the Clinic for Vascular Surgery of the Clinical Centre of Belgrade we operated on 40 patients with renal anomalies and aortic disease (aneurysmatic and obstructive. The retrospective analysis involved standard epidemiological data of each patient (gender, age, risk factors for atherosclerosis, type of anomaly, type of aortic disease, presurgical parameter values of renal function, type of surgical approach (laparatomy or retroperitoneal approach, classification of the renal isthmus, reimplantation of renal arteries and perioperative morbidity and mortality. Results. Twenty patients were males In 30 (70% patients we diagnosed a horse-shoe kidney and in 10 (30% ectopic kidney. In the cases of ruptured aneurysm of the abdominal aorta the diagnosis was made by ultrasound findings. Pre-surgically, renal anomalies were confirmed in all patients, except in those with a ruptured aneurysm who underwent urgent surgery. In all patients we applied medial laparatomy, except in those with a thoracoabdominal aneurysm type IV, when the retroperitonal approach was necessary. On average the patients were under follow-up for 6.2 years (from 6 months to 17 years. Conclusion. Under our conditions, the so-called double clamp technique with the preservation of the kidney gave best results in the patients with renal anomalies and aortic disease.

  3. Gap junction communication in myelinating glia.

    Science.gov (United States)

    Nualart-Marti, Anna; Solsona, Carles; Fields, R Douglas

    2013-01-01

    Gap junction communication is crucial for myelination and axonal survival in both the peripheral nervous system (PNS) and central nervous system (CNS). This review examines the different types of gap junctions in myelinating glia of the PNS and CNS (Schwann cells and oligodendrocytes respectively), including their functions and involvement in neurological disorders. Gap junctions mediate intercellular communication among Schwann cells in the PNS, and among oligodendrocytes and between oligodendrocytes and astrocytes in the CNS. Reflexive gap junctions mediating transfer between different regions of the same cell promote communication between cellular compartments of myelinating glia that are separated by layers of compact myelin. Gap junctions in myelinating glia regulate physiological processes such as cell growth, proliferation, calcium signaling, and participate in extracellular signaling via release of neurotransmitters from hemijunctions. In the CNS, gap junctions form a glial network between oligodendrocytes and astrocytes. This transcellular communication is hypothesized to maintain homeostasis by facilitating restoration of membrane potential after axonal activity via electrical coupling and the re-distribution of potassium ions released from axons. The generation of transgenic mice for different subsets of connexins has revealed the contribution of different connexins in gap junction formation and illuminated new subcellular mechanisms underlying demyelination and cognitive defects. Alterations in metabolic coupling have been reported in animal models of X-linked Charcot-Marie-Tooth disease (CMTX) and Pelizaeus-Merzbarcher-like disease (PMLD), which are caused by mutations in the genes encoding for connexin 32 and connexin 47 respectively. Future research identifying the expression and regulation of gap junctions in myelinating glia is likely to provide a better understanding of myelinating glia in nervous system function, plasticity, and disease. This

  4. Fluxon dynamics in three stacked Josephson junctions

    DEFF Research Database (Denmark)

    Gorria, Carlos; Christiansen, Peter Leth; Gaididei, Yuri Borisovich

    2002-01-01

    /sub -/, the coupling between junctions leads to a repulsion of the fluxons with the same polarity. Above this critical velocity a fluxon will induce radiation in the neighboring junctions, leading to a bunching of the fluxons in the stacked junctions. Using the Sakai-Bodin-Pedersen model, three coupled perturbed sine......-Gordon equations are numerically studied for different values of coupling, damping, and bias parameters. In a narrow range of velocities bunching occurs. Outside this interval the fluxons split and new fluxons may be created. I-V characteristics are presented...

  5. Temperature dependence of thermopower in molecular junctions

    Science.gov (United States)

    Kim, Youngsang; Lenert, Andrej; Meyhofer, Edgar; Reddy, Pramod

    2016-07-01

    The thermoelectric properties of molecular junctions are of considerable interest due to their promise for efficient energy conversion. While the dependence of thermoelectric properties of junctions on molecular structure has been recently studied, their temperature dependence remains unexplored. Using a custom built variable temperature scanning tunneling microscope, we measured the thermopower and electrical conductance of individual benzenedithiol junctions over a range of temperatures (100 K-300 K). We find that while the electrical conductance is independent of temperature, the thermopower increases linearly with temperature, confirming the predictions of the Landauer theory.

  6. Phase qubits fabricated with trilayer junctions

    Energy Technology Data Exchange (ETDEWEB)

    Weides, M; Bialczak, R C; Lenander, M; Lucero, E; Mariantoni, Matteo; Neeley, M; O' Connell, A D; Sank, D; Wang, H; Wenner, J; Yamamoto, T; Yin, Y; Cleland, A N; Martinis, J, E-mail: martin.weides@nist.gov, E-mail: martinis@physics.ucsb.edu [Department of Physics, University of California, Santa Barbara, CA 93106 (United States)

    2011-05-15

    We have developed a novel Josephson junction geometry with minimal volume of lossy isolation dielectric, suitable for higher quality trilayer junctions implemented in qubits. The junctions are based on in situ deposited trilayers with thermal tunnel oxide, have micron-sized areas and a low subgap current. In qubit spectroscopy only a few avoided level crossings are observed, and the measured relaxation time of T{sub 1{approx}}400 ns is in good agreement with the usual phase qubit decay time, indicating low loss due to the additional isolation dielectric.

  7. Radio-frequency shot-noise measurement in a magnetic tunnel junction with a MgO barrier

    Energy Technology Data Exchange (ETDEWEB)

    Rehman, Mushtaq; Park, Junghwan; Song, Woon; Chong, Yonuk [Korea Research Institute of Standards and Science, Daejeon (Korea, Republic of); Lee, Yeonsub; Min, Byoungchul; Shin, Kyungho [Korea Institute of Science and Technology, Seoul (Korea, Republic of); Ryu, Sangwan [Chonnam National University, Gwangju (Korea, Republic of); Khim, Zheong [Seoul National University, Seoul (Korea, Republic of)

    2010-10-15

    We measured the noise power of a magnetic tunnel junction in the frequency range of 710 {approx} 1200 MHz. A low-noise cryogenic HEMT amplifier was used to measure the small noise signal at a high frequency with wide bandwidth. The MgO-barrier tunnel junction showed large tunnel magnetoresistance ratio of 215% at low temperature, which indicates electronic transport through the tunnel barrier without any significant spin-flip scattering. In the bias-dependent noise measurement, however, the zero-bias shot noise was enhanced compared to the value expected from a perfect tunnel barrier or the value observed from a good Al-AlO{sub x}-Al tunnel junction. We assume that this enhanced noise comes from inelastic tunneling processes through the barrier, which may be related to the observed zero-bias anomaly in the differential resistance of the tunnel junctions. We present a simple phenomenological model for how the inelastic scattering process can enhance the zero-bias noise in a tunnel junction.

  8. Gynecologic concerns in patients with cloacal anomaly.

    Science.gov (United States)

    Breech, Lesley

    2016-04-01

    Children with anorectal malformations (ARM) constitute a significant group within a pediatric surgery practice. It is important with female cases of anorectal malformations to consider the association of gynecologic anomalies, especially at the time of the definitive repair. However, it is critical to consider the association of such gynecologic anomalies when caring for patients with a cloacal anomaly. If not recognized, an opportunity to diagnose and treat such anomalies may be missed with the possibility of negative implications for future reproductive capacity. With the knowledge of the associated anomalies and long-term sequelae, surgeons can provide better care for girls and important counseling for parents. Knowledge of reproductive related issues in females with cloaca allows the pediatric surgeon an opportunity both, to provide optimal surgical management in infancy, childhood, and into young adulthood and to collaborate medically and surgically with an experienced gynecologist in patients with more complex anatomic variations. Appropriate counseling for patients and families about potential reproductive concerns that may develop many years after the definitive surgical repair allows preparation and planning to preserve future fertility. Copyright © 2016 Elsevier Inc. All rights reserved.

  9. Geopotential field anomalies and regional tectonic features

    Science.gov (United States)

    Mandea, Mioara; Korte, Monika

    2016-07-01

    Maps of both gravity and magnetic field anomalies offer crucial information about physical properties of the Earth's crust and upper mantle, required in understanding geological settings and tectonic structures. Density and magnetization represent independent rock properties and thus provide complementary information on compositional and structural changes. Two regions are considered: southern Africa (encompassing South Africa, Namibia and Botswana) and Germany. This twofold choice is motivated firstly by the fact that these regions represent rather diverse geological and geophysical conditions (old Archean crust with strong magnetic anomalies in southern Africa, and much younger, weakly magnetized crust in central Europe) and secondly by our intimate knowledge of the magnetic vector ground data from these two regions. We take also advantage of the recently developed satellite potential field models and compare magnetic and gravity gradient anomalies of some 200 km resolution. Comparing short and long wavelength anomalies and the correlation of rather large scale magnetic and gravity anomalies, and relating them to known lithospheric structures, we generally find a better agreement over the southern African region than the German territory. This probably indicates a stronger concordance between near-surface and deeper structures in the former area, which can be perceived to agree with a thicker lithosphere.

  10. Etiology and Evaluation of Sperm Chromatin Anomalies

    Directory of Open Access Journals (Sweden)

    Marziyeh Tavalaee

    2008-01-01

    Full Text Available Evidence suggests that human sperm chromatin anomalies adversely affect reproductive outcomesand infertile men possess substantially amount of sperm with chromatin anomalies than fertilemen.Routine semen analysis evaluates parameters such as sperm motility and morphology, but doesnot examine the nuclear DNA integrity of spermatozoa. It has been suggested that altered nuclearchromatin structure or damaged DNA in spermatozoa could modify the special cellular functionsof human spermatozoa, and thereby affect the fertility potential. Intra-cytoplasmic sperm injection(ICSI bypass the barriers to fertilization for such a sperm, then the effect of chromatin anomalies onthe development remains a concern. Therefore, it is essential to develop and use accurate diagnostictests, which may provide better prognostic capabilities than the standard sperm assessments. Thisreview discusses our current understanding of the structure and organization of sperm DNA,the different procedures for assessment of sperm chromatin anomalies including comet assay,Chromomycin A3 (CMA3, sperm chromatin structure assay (SCSA, acridine orange test (AOT,terminal TdT-mediated dUTP-nick-end labelling (TUNEL assay, aniline blue and sperm chromatindispersion (SCD test and the impact of chromatin anomalies on reproductive outcome.

  11. Increasing gap junctional coupling: a tool for dissecting the role of gap junctions.

    Science.gov (United States)

    Axelsen, Lene Nygaard; Haugan, Ketil; Stahlhut, Martin; Kjølbye, Anne-Louise; Hennan, James K; Holstein-Rathlou, Niels-Henrik; Petersen, Jørgen Søberg; Nielsen, Morten Schak

    2007-03-01

    Much of our current knowledge about the physiological and pathophysiological role of gap junctions is based on experiments where coupling has been reduced by either chemical agents or genetic modification. This has brought evidence that gap junctions are important in many physiological processes. In a number of cases, gap junctions have been implicated in the initiation and progress of disease, and experimental uncoupling has been used to investigate the exact role of coupling. The inverse approach, i.e., to increase coupling, has become possible in recent years and represents a new way of testing the role of gap junctions. The aim of this review is to summarize the current knowledge obtained with agents that selectively increase gap junctional intercellular coupling. Two approaches will be reviewed: increasing coupling by the use of antiarrhythmic peptide and its synthetic analogs and by interfering with the gating of gap junctional channels.

  12. Presynaptic spike broadening reduces junctional potential amplitude.

    Science.gov (United States)

    Spencer, A N; Przysiezniak, J; Acosta-Urquidi, J; Basarsky, T A

    1989-08-24

    Presynaptic modulation of action potential duration may regulate synaptic transmission in both vertebrates and invertebrates. Such synaptic plasticity is brought about by modifications to membrane currents at presynaptic release sites, which, in turn, lead to changes in the concentration of cytosolic calcium available for mediating transmitter release. The 'primitive' neuromuscular junction of the jellyfish Polyorchis penicillatus is a useful model of presynaptic modulation. In this study, we show that the durations of action potentials in the motor neurons of this jellyfish are negatively correlated with the amplitude of excitatory junctional potentials. We present data from in vitro voltage-clamp experiments showing that short duration voltage spikes, which elicit large excitatory junctional potentials in vivo, produce larger and briefer calcium currents than do long duration action potentials, which elicit small excitatory junctional potentials.

  13. Laparoscopically assisted pyeloplasty for ureteropelvic junction ...

    African Journals Online (AJOL)

    junction obstruction: a transperitoneal versus a retroperitoneal approach ... laparoscopic-assisted dismembered pyeloplasty (TLADP) ... to an open technique for two patients of the TLADP group; ... Annals of Pediatric Surgery 2012, 8:29–31.

  14. Tight Junctions in Salivary Epithelium

    Directory of Open Access Journals (Sweden)

    Olga J. Baker

    2010-01-01

    Full Text Available Epithelial cell tight junctions (TJs consist of a narrow belt-like structure in the apical region of the lateral plasma membrane that circumferentially binds each cell to its neighbor. TJs are found in tissues that are involved in polarized secretions, absorption functions, and maintaining barriers between blood and interstitial fluids. The morphology, permeability, and ion selectivity of TJ vary among different types of tissues and species. TJs are very dynamic structures that assemble, grow, reorganize, and disassemble during physiological or pathological events. Several studies have indicated the active role of TJ in intestinal, renal, and airway epithelial function; however, the functional significance of TJ in salivary gland epithelium is poorly understood. Interactions between different combinations of the TJ family (each with their own unique regulatory proteins define tissue specificity and functions during physiopathological processes; however, these interaction patterns have not been studied in salivary glands. The purpose of this review is to analyze some of the current data regarding the regulatory components of the TJ that could potentially affect cellular functions of the salivary epithelium.

  15. Anomaly-based Network Intrusion Detection Methods

    Directory of Open Access Journals (Sweden)

    Pavel Nevlud

    2013-01-01

    Full Text Available The article deals with detection of network anomalies. Network anomalies include everything that is quite different from the normal operation. For detection of anomalies were used machine learning systems. Machine learning can be considered as a support or a limited type of artificial intelligence. A machine learning system usually starts with some knowledge and a corresponding knowledge organization so that it can interpret, analyse, and test the knowledge acquired. There are several machine learning techniques available. We tested Decision tree learning and Bayesian networks. The open source data-mining framework WEKA was the tool we used for testing the classify, cluster, association algorithms and for visualization of our results. The WEKA is a collection of machine learning algorithms for data mining tasks.

  16. Anomaly mediation in local effective theories

    Energy Technology Data Exchange (ETDEWEB)

    Dine, Michael; Draper, Patrick [Santa Cruz Institute for Particle Physics and Department of Physics,Santa Cruz CA 95064 (United States)

    2014-02-17

    The phenomenon known as “anomaly mediation” can be understood in a variety of ways. Rather than an anomaly, certain gaugino bilinear terms are required by local supersymmetry and gauge invariance (the derivation of these terms is in some cases related to anomalies in scale invariance or R symmetries). We explain why the gaugino bilinear is required in supersymmetric gauge theories with varying number of colors and flavors. By working in the Higgs phase, gauging a flavor group, or working below the scale of gaugino condensation, each of these theories has a local effective description in which we can identify the bilinear term, establishing its necessity in the microscopic theory. For example, in theories that exhibit gaugino condensation, the potential in the very low energy theory is supersymmetric precisely due to the relation between the nonperturbative superpotential and the gaugino bilinear terms. Similarly, the gravitino mass appears from its coupling to the gaugino bilinear.

  17. The Anomaly Structure of Regularized Supergravity

    CERN Document Server

    Butter, Daniel

    2014-01-01

    On-shell Pauli-Villars regularization of the one-loop divergences of supergravity theories is used to study the anomaly structure of supergravity and the cancellation of field theory anomalies under a $U(1)$ gauge transformation and under the T-duality group of modular transformations in effective supergravity theories with three K\\"ahler moduli $T^i$ obtained from orbifold compactification of the weakly coupled heterotic string. This procedure requires constraints on the chiral matter representations of the gauge group that are consistent with known results from orbifold compactifications. Pauli-Villars regulator fields allow for the cancellation of all quadratic and logarithmic divergences, as well as most linear divergences. If all linear divergences were canceled, the theory would be anomaly free, with noninvariance of the action arising only from Pauli-Villars masses. However there are linear divergences associated with nonrenormalizable gravitino/gaugino interactions that cannot be canceled by PV fields...

  18. Neutrino anomalies and large extra dimensions

    CERN Document Server

    Dighe, A S; Dighe, Amol S.; Joshipura, Anjan S.

    2001-01-01

    Theories with large extra dimensions can generate small neutrino masses when the standard model neutrinos are coupled to singlet fermions propagating in higher dimensions. The couplings can also generate mass splittings and mixings among the flavour neutrinos in the brane. We systematically study the minimal scenario involving only one singlet bulk fermion coupling weakly to the flavour neutrinos. We explore the neutrino mass structures in the brane that can potentially account for the atmospheric, solar and LSND anomalies simultaneously in a natural way. We demonstrate that in the absence of a priori mixings among the SM neutrinos, it is not possible to reconcile all these anomalies. The presence of some structure in the mass matrix of the SM neutrinos can solve this problem. This is exemplified by the Zee model, which when embedded in extra dimensions in a minimal way can account for all the neutrino anomalies.

  19. Gauge Anomalies and Neutrino Seesaw Models

    CERN Document Server

    Neves Cebola, Luis Manuel

    Despite the success of the Standard Model concerning theoretical predictions, there are several experimental results that cannot be explained and there are reasons to believe that there exists new physics beyond it. Neutrino oscillations, and hence their masses, are examples of this. Experimentally it is known that neutrinos masses are quite small, when compared to all Standard Model particle masses. Among the theoretical possibilities to explain these tiny masses, the seesaw mechanism is a simple and well-motivated framework. In its minimal version, heavy particles are introduced that decouple from the theory in the early universe. To build consistent theories, classical symmetries need to be preserved at quantum level, so that there are no anomalies. The cancellation of these anomalies leads to constraints in the parameters of the theory. One attractive solution is to realize the anomaly cancellation through the modication of the gauge symmetry. In this thesis we present a short review of some features of t...

  20. An Immune Inspired Approach to Anomaly Detection

    CERN Document Server

    Twycross, Jamie

    2009-01-01

    The immune system provides a rich metaphor for computer security: anomaly detection that works in nature should work for machines. However, early artificial immune system approaches for computer security had only limited success. Arguably, this was due to these artificial systems being based on too simplistic a view of the immune system. We present here a second generation artificial immune system for process anomaly detection. It improves on earlier systems by having different artificial cell types that process information. Following detailed information about how to build such second generation systems, we find that communication between cells types is key to performance. Through realistic testing and validation we show that second generation artificial immune systems are capable of anomaly detection beyond generic system policies. The paper concludes with a discussion and outline of the next steps in this exciting area of computer security.

  1. Androgen-Dependent Sertoli Cell Tight Junction Remodeling Is Mediated by Multiple Tight Junction Components

    National Research Council Canada - National Science Library

    Chakraborty, Papia; William Buaas, F; Sharma, Manju; Smith, Benjamin E; Greenlee, Anne R; Eacker, Stephen M; Braun, Robert E

    2014-01-01

    Sertoli cell tight junctions (SCTJs) of the seminiferous epithelium create a specialized microenvironment in the testis to aid differentiation of spermatocytes and spermatids from spermatogonial stem cells...

  2. Junction Plasmon-Induced Molecular Reorientation

    Energy Technology Data Exchange (ETDEWEB)

    El-Khoury, Patrick Z.; Hu, Dehong; Hess, Wayne P.

    2013-10-17

    Time and frequency dependent intensity variations in sequences of Raman spectra recorded at plasmonic junctions can be assigned to molecular reorientation. This is revealed through Raman trajectories recorded at a nanojunction formed between a silver AFM tip and a corrugated silver surface coated with biphenyl-4,4’-dithiol. Molecular motion is not observed when the tip is retracted and only surface enhancement is operative. In effect, junction plasmon induced molecular reorientation is tracked.

  3. [Clinical anatomy of the esophagogastric junction].

    Science.gov (United States)

    Tănase, M; Aldea, A S

    2012-01-01

    The esophagogastric junction is a controversial anatomical area, due to its sphincteric mechanism which does not show an obvious anatomical basis. The aim of this study is to investigate the anatomical components that endoscopically indicate the mucosal esophagogastric junction in hiatal hernia patients. The esophagogastric junction was investigated in 27 hiatal hernia patients undergoing surgery. Hiatal hernia is an extension of the stomach situated between the esophagogastric junction and the diaphragmatic indentation. The following types of hiatal hernia were found: sliding hiatal hernia (type I) in 4 patients (14.81%), rolling hiatal hernia (type II) in 2 (7.4%), mixed hiatal hernia (type III) in 12 (44.44%), type IV hiatal hernia in 4 (14.81%) and recurrent hiatal hernia in 5 (18.51%). Of the 27 hiatal hernia patients, 8 (29.6%) were operated using classical procedures: laparotomy--6 (75%) and laparoscopic surgery--2 (25%). The angle of His cannot be used for marking the mucosal esophagogastric junction due to the severe damage of the lower esophageal sphincter in hiatal hernia patients. The squamocolumnar junction is displaced in hiatal hernia patients and was not an option for the study group. The distal end of the esophageal longitudinal palisading vessels needs medication (proton pump inhibitors that reduce the gastric acid production), in order to enhance the visibility of these vessels. The proximal end of gastric longitudinal mucosal folds proved to be the most reliable site to identify endoscopically the mucosal esophagogastric junction. The anatomical structure of the esophagogastric junction differs in hiatal hernia patients and these peculiarities are very important in surgery.

  4. The Dissolution of Double Holliday Junctions

    DEFF Research Database (Denmark)

    Bizard, Anna H; Hickson, Ian D

    2014-01-01

    as "double Holliday junction dissolution." This reaction requires the cooperative action of a so-called "dissolvasome" comprising a Holliday junction branch migration enzyme (Sgs1/BLM RecQ helicase) and a type IA topoisomerase (Top3/TopoIIIα) in complex with its OB (oligonucleotide/oligosaccharide binding......) fold containing accessory factor (Rmi1). This review details our current knowledge of the dissolution process and the players involved in catalyzing this mechanistically complex means of completing homologous recombination reactions....

  5. Associated congenital anomalies among cases with Down syndrome.

    Science.gov (United States)

    Stoll, Claude; Dott, Beatrice; Alembik, Yves; Roth, Marie-Paule

    2015-12-01

    Down syndrome (DS) is the most common congenital anomaly widely studied for at least 150 years. However, the type and the frequency of congenital anomalies associated with DS are still controversial. Despite prenatal diagnosis and elective termination of pregnancy for fetal anomalies, in Europe, from 2008 to 2012 the live birth prevalence of DS per 10,000 was 10. 2. The objectives of this study were to examine the major congenital anomalies occurring in infants and fetuses with Down syndrome. The material for this study came from 402,532 consecutive pregnancies of known outcome registered by our registry of congenital anomalies between 1979 and 2008. Four hundred sixty seven (64%) out of the 728 cases with DS registered had at least one major associated congenital anomaly. The most common associated anomalies were cardiac anomalies, 323 cases (44%), followed by digestive system anomalies, 42 cases (6%), musculoskeletal system anomalies, 35 cases (5%), urinary system anomalies, 28 cases (4%), respiratory system anomalies, 13 cases (2%), and other system anomalies, 26 cases (3.6%). Among the cases with DS with congenital heart defects, the most common cardiac anomaly was atrioventricular septal defect (30%) followed by atrial septum defect (25%), ventricular septal defect (22%), patent ductus arteriosus (5%), coarctation of aorta (5%), and tetralogy of Fallot (3%). Among the cases with DS with a digestive system anomaly recorded, duodenal atresia (67%), Hirschsprung disease (14%), and tracheo-esophageal atresia (10%) were the most common. Fourteen (2%) of the cases with DS had an obstructive anomaly of the renal pelvis, including hydronephrosis. The other most common anomalies associated with cases with DS were syndactyly, club foot, polydactyly, limb reduction, cataract, hydrocephaly, cleft palate, hypospadias and diaphragmatic hernia. Many studies to assess the anomalies associated with DS have reported various results. There is no agreement in the literature as to

  6. Global anomalies in Chiral Lattice Gauge Theory

    Science.gov (United States)

    Bär, Oliver; Campos, Isabel

    As first realized by Witten an SU(2) gauge theory coupled to a single Weyl fermion suffers from a global anomaly. This problem is addressed here in the context of the recent developments on chiral gauge theories on the lattice. We find Witten's anomaly manifests in the impossibility of defining globally a fermion measure that reproduces the proper continuum limit. Moreover, following Witten's original argument, we check numerically the crossing of the lowest eigenvalues of Neuberger's operator along a path connecting two gauge fields that differ by a topologically non-trivial gauge transformation.

  7. Radioactive anomaly discrimination from spectral ratios

    Science.gov (United States)

    Maniscalco, James; Sjoden, Glenn; Chapman, Mac Clements

    2013-08-20

    A method for discriminating a radioactive anomaly from naturally occurring radioactive materials includes detecting a first number of gamma photons having energies in a first range of energy values within a predetermined period of time and detecting a second number of gamma photons having energies in a second range of energy values within the predetermined period of time. The method further includes determining, in a controller, a ratio of the first number of gamma photons having energies in the first range and the second number of gamma photons having energies in the second range, and determining that a radioactive anomaly is present when the ratio exceeds a threshold value.

  8. Singlet deflected anomaly/gauge mediation

    Energy Technology Data Exchange (ETDEWEB)

    Blas, J. de, E-mail: jdeblasm@nd.edu [Department of Physics, University of Notre Dame, Notre Dame, IN 46556 (United States); Delgado, A., E-mail: antonio.delgado@nd.edu [Department of Physics, University of Notre Dame, Notre Dame, IN 46556 (United States)

    2012-02-28

    We study an extension of the standard anomaly/gauge mediation scenario where the messenger fields have direct interactions with an extra gauge singlet. This realizes a phenomenologically viable NMSSM-like scenario free of the {mu}-b{sub {mu}} problem. Current cosmological constraints imply a small size for the anomaly-mediation contributions, unless some source of R-parity violation is permitted. In the latter case the allowed regions in the parameter space can be substantially larger than in the corresponding gauge-mediation scenario.

  9. Experimental Signatures of Anomaly Induced DCC Formation

    CERN Document Server

    Asakawa, M; Müller, B

    2002-01-01

    We discuss possible experimental signatures related to the formation of domains of disoriented chiral condensate (DCC) triggered by the axial anomaly in relativistic heavy ion collisions. Our predictions make use of the feature of the anomaly effect that is coherent over a large region of space, but opposite in sign above and below the ion scattering plane. We predict an enhancement of the fraction of neutral pions compared to all pions, which depends on the angle of emission with respect to the scattering plane and is concentrated at small transverse momentum and small rapidity in the center-of-mass frame.

  10. The GSI Time Anomaly: Facts and Fiction

    CERN Document Server

    Giunti, Carlo

    2009-01-01

    The claims that the GSI time anomaly is due to the mixing of neutrinos in the final state of the observed electron-capture decays of hydrogen-like heavy ions are refuted with the help of an analogy with a double-slit experiment. It is a consequence of causality. It is shown that the GSI time anomaly may be caused by quantum beats due to the existence of two coherent energy levels of the decaying ion with an extremely small energy splitting (about $6\\times10^{-16} \\text{eV}$) and relative probabilities having a ratio of about 1/99.

  11. Purely Four-dimensional Viable Anomaly Mediation

    CERN Document Server

    Harnik, R; Pierce, A T; Harnik, Roni; Murayama, Hitoshi; Pierce, Aaron

    2002-01-01

    Anomaly mediation of supersymmetry breaking solves the supersymmetric flavor problem thanks to its ultraviolet-insensitivity. However, it suffers from two problems: sleptons have negative masses-squared, and there are likely bulk moduli that spoil the framework. Here, we present the first fully ultraviolet-insensitive model of anomaly mediation with positive slepton masses-squared in a purely four-dimensional framework. Our model is based on the additional D-term contributions to the sparticle masses of Arkani-Hamed, Kaplan, HM, and Nomura, and the conformal sequestering mechanism of Luty and Sundrum.

  12. A rare anomaly of abductor digiti minimi.

    Science.gov (United States)

    Sañudo, J R; Mirapeix, R M; Ferreira, B

    1993-06-01

    Two cases with anomalous fascicles in abductor digiti minimi, noted in the course of dissecting 62 adult postmortem forearms, are described. Both fascicles arose from the flexor retinaculum and the antebrachial fascia; one was inserted into abductor digiti minimi and the other on the proximal phalanx of the 5th finger. The anomalous muscles crossed the ulnar nerve and in 1 case also the median nerve. In the 2nd case the palmar nerve to the 5th finger was seen to penetrate the anomalous muscle. The ontogeny, morphology and clinical significance of this anomaly are discussed in relation to previously described anomalies of the hypothenar muscles.

  13. Gauge mediated supersymmetry breaking and neutrino anomalies

    CERN Document Server

    Joshipura, A S; Joshipura, Anjan S.; Vempati, Sudhir K.

    1999-01-01

    Supersymmetric standard model with softly broken lepton symmetry provides a suitable framework to accommodate the solar and atmospheric neutrino anomalies. This model contains a natural explanation for large mixing and hierarchal masses without fine tuning of the parameters. Neutrino spectrum is particularly constrained in the minimal messenger model (MMM) of gauge mediated SUSY breaking, since all SUSY breaking effects are controlled in MMM by a single parameter. We study the structure of neutrino masses and mixing both in MMM and in simple extensions of it in the context of solar and atmospheric neutrino anomalies.

  14. The Role of Imaging in Craniofacial Anomalies

    Directory of Open Access Journals (Sweden)

    P. Alipour

    2008-01-01

    Full Text Available It is important to know craniofacial anatomy in infancy for early detection of craniofacial anomalies, to help the surgeon's decision ,for repair and increase the patients, quality of life .In this regard, imaging has the major role in preoperative diagnostic maping and post operative follow up repair."nWe are going to show the normal craniofacial anatomy appearances in infancy in order to detect early craniofacial anomaly and syndromatic craniosynostosis with plain skull X-ray and CT scan reconstruction imaging.

  15. Gap junction intercellular communication and benzene toxicity.

    Science.gov (United States)

    Rivedal, Edgar; Witz, Gisela; Leithe, Edward

    2010-03-19

    Aberrant regulation of gap junction intercellular communication (GJIC) has been linked to several human diseases, including cancer and abnormal hematopoietic development. Benzene exposure has been shown to cause hematotoxicity and leukemia, but the underlying mechanisms involved remain unclear. We have observed that several metabolites of benzene have the ability to block gap junction intercellular communication. The ring-opened trans,trans-muconaldehyde (MUC) was found to be the most potent inhibitor of gap junction channels. MUC was found to induce cross-linking of the gap junction protein connexin43, which seemed to be responsible for the induced inhibition of GJIC. Glutaraldehyde, which has a similar molecular structure as MUC, was found to possess similar effects on gap junctions as MUC, while the mono-aldehyde formaldehyde shows lower potency, both as a connexin cross-linker, and as an inhibitor of GJIC. Both glutaraldehyde and formaldehyde have previously been associated with induction of leukemia and disturbance of hematopoiesis. Taken together, the data support a possible link between the effect of MUC on gap junctions, and the toxic effects of benzene. Copyright (c) 2009 Elsevier Ireland Ltd. All rights reserved.

  16. Gap junctions: structure and function (Review).

    Science.gov (United States)

    Evans, W Howard; Martin, Patricia E M

    2002-01-01

    Gap junctions are plasma membrane spatial microdomains constructed of assemblies of channel proteins called connexins in vertebrates and innexins in invertebrates. The channels provide direct intercellular communication pathways allowing rapid exchange of ions and metabolites up to approximately 1 kD in size. Approximately 20 connexins are identified in the human or mouse genome, and orthologues are increasingly characterized in other vertebrates. Most cell types express multiple connexin isoforms, making likely the construction of a spectrum of heteromeric hemichannels and heterotypic gap junctions that could provide a structural basis for the charge and size selectivity of these intercellular channels. The precise nature of the potential signalling information traversing junctions in physiologically defined situations remains elusive, but extensive progress has been made in elucidating how connexins are assembled into gap junctions. Also, participation of gap junction hemichannels in the propagation of calcium waves via an extracellular purinergic pathway is emerging. Connexin mutations have been identified in a number of genetically inherited channel communication-opathies. These are detected in connexin 32 in Charcot Marie Tooth-X linked disease, in connexins 26 and 30 in deafness and skin diseases, and in connexins 46 and 50 in hereditary cataracts. Biochemical approaches indicate that many of the mutated connexins are mistargeted to gap junctions and/or fail to oligomerize correctly into hemichannels. Genetic ablation approaches are helping to map out a connexin code and point to specific connexins being required for cell growth and differentiation as well as underwriting basic intercellular communication.

  17. Predictive modelling of ferroelectric tunnel junctions

    Science.gov (United States)

    Velev, Julian P.; Burton, John D.; Zhuravlev, Mikhail Ye; Tsymbal, Evgeny Y.

    2016-05-01

    Ferroelectric tunnel junctions combine the phenomena of quantum-mechanical tunnelling and switchable spontaneous polarisation of a nanometre-thick ferroelectric film into novel device functionality. Switching the ferroelectric barrier polarisation direction produces a sizable change in resistance of the junction—a phenomenon known as the tunnelling electroresistance effect. From a fundamental perspective, ferroelectric tunnel junctions and their version with ferromagnetic electrodes, i.e., multiferroic tunnel junctions, are testbeds for studying the underlying mechanisms of tunnelling electroresistance as well as the interplay between electric and magnetic degrees of freedom and their effect on transport. From a practical perspective, ferroelectric tunnel junctions hold promise for disruptive device applications. In a very short time, they have traversed the path from basic model predictions to prototypes for novel non-volatile ferroelectric random access memories with non-destructive readout. This remarkable progress is to a large extent driven by a productive cycle of predictive modelling and innovative experimental effort. In this review article, we outline the development of the ferroelectric tunnel junction concept and the role of theoretical modelling in guiding experimental work. We discuss a wide range of physical phenomena that control the functional properties of ferroelectric tunnel junctions and summarise the state-of-the-art achievements in the field.

  18. Tectonic history of the north portion of the San Andreas fault system, California, inferred from gravity and magnetic anomalies

    Science.gov (United States)

    Griscom, A.; Jachens, R.C.

    1989-01-01

    Geologic and geophysical data for the San Andreas fault system north of San Francisco suggest that the eastern boundary of the Pacific plate migrated eastward from its presumed original position at the base of the continental slope to its present position along the San Andreas transform fault by means of a series of eastward jumps of the Mendocino triple junction. These eastward jumps total a distance of about 150 km since 29 Ma. Correlation of right-laterally displaced gravity and magnetic anomalies that now have components at San Francisco and on the shelf north of Point Arena indicates that the presently active strand of the San Andreas fault north of the San Francisco peninsula formed recently at about 5 Ma when the triple junction jumped eastward a minimum of 100 km to its present location at the north end of the San Andreas fault. -from Authors

  19. Charge transport in nanoscale junctions.

    Science.gov (United States)

    Albrecht, Tim; Kornyshev, Alexei; Bjørnholm, Thomas

    2008-09-03

    many particle excitations, new surface states in semiconductor electrodes, various mechanisms for single molecule rectification of the current, inelastic electron spectra and SERS spectroscopy. Three terminal architectures allowing (electrochemical) gating and transistor effects. Electrochemical nanojunctions and gating: intermolecular electron transfer in multi-redox metalloproteins, contact force modulation, characteristic current-noise patterns due to conformational fluctuations, resonance effects and electrocatalysis. Novel architectures: linear coupled quantum-dot-bridged junctions, electrochemical redox mediated transfer in two center systems leading to double maxima current-voltage plots and negative differential resistance, molecular-nanoparticle hybrid junctions and unexpected mesoscopic effects in polymeric wires. Device integration: techniques for creating stable metal/molecule/metal junctions using 'nano-alligator clips' and integration with 'traditional' silicon-based technology. The Guest Editors would like to thank all of the authors and referees of this special issue for their meticulous work in making each paper a valuable contribution to this research area, the early-bird authors for their patience, and Journal of Physics: Condensed Matter editorial staff in Bristol for their continuous support.

  20. A Natural origin for the LHCb anomalies

    CERN Document Server

    Megias, Eugenio; Pujolas, Oriol; Quiros, Mariano

    2016-01-01

    The anomalies recently found by the LHCb collaboration in $B$-meson decays seem to point towards the existence of new physics coupled non-universally to muons and electrons. We show that a beyond-the-Standard-Model dynamics with these features naturally arises in models with a warped extra-dimension that aim to solve the electroweak Hierarchy Problem. The attractiveness of our set-up is the fact that the dynamics responsible for generating the flavor anomalies is automatically present, being provided by the massive Kaluza--Klein excitations of the electroweak gauge bosons. The flavor anomalies can be easily reproduced by assuming that the bottom and muon fields have a sizable amount of compositeness, while the electron is almost elementary. Interestingly enough, this framework correlates the flavor anomalies to a pattern of corrections in the electroweak observables and in flavor-changing processes. In particular the deviations in the bottom and muon couplings to the $Z$-boson and in $\\Delta F = 2$ flavor-cha...

  1. Hyperspectral anomaly detection using enhanced global factors

    Science.gov (United States)

    Paciencia, Todd J.; Bauer, Kenneth W.

    2016-05-01

    Dimension reduction techniques have become one popular unsupervised approach used towards detecting anomalies in hyperspectral imagery. Although demonstrating promising results in the literature on specific images, these methods can become difficult to directly interpret and often require tuning of their parameters to achieve high performance on a specific set of images. This lack of generality is also compounded by the need to remove noise and atmospheric absorption spectral bands from the image prior to detection. Without a process for this band selection and to make the methods adaptable to different image compositions, performance becomes difficult to maintain across a wider variety of images. Here, we present a framework that uses factor analysis to provide a robust band selection and more meaningful dimension reduction with which to detect anomalies in the imagery. Measurable characteristics of the image are used to create an automated decision process that allows the algorithm to adjust to a particular image, while maintaining high detection performance. The framework and its algorithms are detailed, and results are shown for forest, desert, sea, rural, urban, anomaly-sparse, and anomaly-dense imagery types from different sensors. Additionally, the method is compared to current state-of-the-art methods and is shown to be computationally efficient.

  2. Alaska Terrain Corrected Free Air Anomalies (96)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This 2' x 4' gravity anomaly grid for Alaska is NOT the input data set used in development of the GEOID96 model. This gravity grid models the 1.1 million terrestrial...

  3. A Methodological Overview on Anomaly Detection

    NARCIS (Netherlands)

    Callegari, C.; Coluccia, A.; D'Alconzo, A.; Ellens, W.; Giordano, S.; Mandjes, M.; Pagano, P.; Pepe, T.; Ricciato, F.; Żuraniewski, P.; Biersack, E.; Callegari, C.; Matijasevic, M.

    2013-01-01

    In this Chapter we give an overview of statistical methods for anomaly detection (AD), thereby targeting an audience of practitioners with general knowledge of statistics. We focus on the applicability of the methods by stating and comparing the conditions in which they can be applied and by discuss

  4. A methodological overview on anomaly detection

    NARCIS (Netherlands)

    Callegari, C.; Coluccia, A.; D'alconzo, A.; Ellens, W.; Giordano, S.; Mandjes, M.; Pagano, M.; Pepe, T.; Ricciato, F.; Zuraniewski, P.W.

    2013-01-01

    In this Chapter we give an overview of statistical methods for anomaly detection (AD), thereby targeting an audience of practitioners with general knowledge of statistics. We focus on the applicability of the methods by stating and comparing the conditions in which they can be applied and by discuss

  5. Detection of cardiovascular anomalies: Hybrid systems approach

    KAUST Repository

    Ledezma, Fernando

    2012-06-06

    In this paper, we propose a hybrid interpretation of the cardiovascular system. Based on a model proposed by Simaan et al. (2009), we study the problem of detecting cardiovascular anomalies that can be caused by variations in some physiological parameters, using an observerbased approach. We present the first numerical results obtained. © 2012 IFAC.

  6. Seasonality of Congenital Anomalies in Europe

    NARCIS (Netherlands)

    Luteijn, Johannes Michiel; Dolk, Helen; Addor, Marie-Claude; Arriola, Larraitz; Barisic, Ingeborg; Bianchi, Fabrizio; Calzolari, Elisa; Draper, Elizabeth; Garne, Ester; Gatt, Miriam; Haeusler, Martin; Khoshnood, Babak; McDonnell, Bob; Nelen, Vera; O'Mahony, Mary; Mullaney, Carmel; Queisser-Luft, Annette; Rankin, Judith; Tucker, David; Verellen-Dumoulin, Christine; de Walle, Hermien; Yevtushok, Lyubov

    2014-01-01

    BackgroundThis study describes seasonality of congenital anomalies in Europe to provide a baseline against which to assess the impact of specific time varying exposures such as the H1N1 pandemic influenza, and to provide a comprehensive and recent picture of seasonality and its possible relation to

  7. Psychoeducational Implications of Sex Chromosome Anomalies

    Science.gov (United States)

    Wodrich, David L.; Tarbox, Jennifer

    2008-01-01

    Numerous anomalies involving the sex chromosomes (X or Y) have been documented and their impact on development, learning, and behavior studied. This article reviews three of these disorders, Turner syndrome, Klinefelter syndrome, and Lesch-Nyhan disease. Each of these three is associated with one or more selective impairments or behavioral…

  8. Conformal Anomaly and Counterterms in Designer Gravity

    CERN Document Server

    Anabalon, Andres; Choque, David; Martinez, Cristian

    2015-01-01

    We construct concrete counterterms of the Balasubramanian-Kraus type for Einstein-scalar theories with designer gravity boundary conditions in AdS$_{4}$, so that the total action is finite on-shell and satisfy a well defined variational principle for an arbitrary scalar field potential. We focus on scalar fields with the conformal mass, $m^{2}=-2l^{-2}$, and show that the holographic mass matches the Hamiltonian mass for any boundary conditions. We compute the conformal anomaly of the dual field theory in the generic case, as well as when there exist logarithmic branches of non-linear origin. As expected, the conformal anomaly vanishes for the boundary conditions that are AdS invariant. When the anomaly does not vanish, the dual stress tensor describes a thermal gas with an equation of state related to the boundary conditions of the scalar field. When the anomaly vanishes, we recover the dual theory of a massless thermal gas. As an application of the formalism, we consider a general family of exact hairy blac...

  9. Congenital spine anomalies: the closed spinal dysraphisms

    Energy Technology Data Exchange (ETDEWEB)

    Schwartz, Erin Simon [University of Pennsylvania, Department of Radiology, The Children' s Hospital of Philadelphia, Perelman School of Medicine, Philadelphia, PA (United States); Rossi, Andrea [G. Gaslini Children' s Hospital, Department of Radiology, Genoa (Italy)

    2015-09-15

    The term congenital spinal anomalies encompasses a wide variety of dysmorphology that occurs during early development. Familiarity with current terminology and a practical, clinico-radiologic classification system allows the radiologist to have a more complete understanding of malformations of the spine and improves accuracy of diagnosis when these entities are encountered in practice. (orig.)

  10. Anomaly Detection using the "Isolation Forest" algorithm

    CERN Document Server

    CERN. Geneva

    2015-01-01

    Anomaly detection can provide clues about an outlying minority class in your data: hackers in a set of network events, fraudsters in a set of credit card transactions, or exotic particles in a set of high-energy collisions. In this talk, we analyze a real dataset of breast tissue biopsies, with malignant results forming the minority class. The "Isolation Forest" algorithm finds anomalies by deliberately “overfitting” models that memorize each data point. Since outliers have more empty space around them, they take fewer steps to memorize. Intuitively, a house in the country can be identified simply as “that house out by the farm”, while a house in the city needs a longer description like “that house in Brooklyn, near Prospect Park, on Union Street, between the firehouse and the library, not far from the French restaurant”. We first use anomaly detection to find outliers in the biopsy data, then apply traditional predictive modeling to discover rules that separate anomalies from normal data...

  11. A natural origin for the LHCb anomalies

    Science.gov (United States)

    Megías, Eugenio; Panico, Giuliano; Pujolàs, Oriol; Quirós, Mariano

    2016-09-01

    The anomalies recently found by the LHCb collaboration in B-meson decays seem to point towards the existence of new physics coupled non-universally to muons and electrons. We show that a beyond-the-Standard-Model dynamics with these features naturally arises in models with a warped extra-dimension that aim to solve the electroweak Hierarchy Problem. The attractiveness of our set-up is the fact that the dynamics responsible for generating the flavor anomalies is automatically present, being provided by the massive Kaluza-Klein excitations of the electroweak gauge bosons. The flavor anomalies can be easily reproduced by assuming that the bottom and muon fields have a sizable amount of compositeness, while the electron is almost elementary. Interestingly enough, this framework correlates the flavor anomalies to a pattern of corrections in the electroweak observables and in flavor-changing processes. In particular the deviations in the bottom and muon couplings to the Z-boson and in Δ F = 2 flavor-changing observables are predicted to be close to the present experimental bounds, and thus potentially testable in near-future experiments.

  12. Contextual Detection of Anomalies within Hyperspectral Images

    Science.gov (United States)

    2011-03-01

    Hyperspectral Imagery (HSI), Unsupervised Target Detection, Target Identification, Contextual Anomaly Detection 16. SECURITY CLASSIFICATION OF: 17. LIMITATION...processing. Hyperspectral imaging has a wide range of applications within remote sensing, not limited to terrain classification , environmental monitoring...Johnson, R. J. (2008). Improved feature extraction, feature selection, and identification techniques that create a fast unsupervised hyperspectral

  13. Reducing customer minutes lost by anomaly detection?

    NARCIS (Netherlands)

    Bakker, M.; Vreeburg, J.H.G.; Rietveld, L.C.; van der Roer, M.

    2012-01-01

    An method which compares measured and predicted water demands to detect anomalies, was developed and tested on three data sets of water demand of three years in which and 25 pipe bursts were reported. The method proved to be able to detect bursts where the water loss exceeds 30% of the average water

  14. Psychoeducational Implications of Sex Chromosome Anomalies

    Science.gov (United States)

    Wodrich, David L.; Tarbox, Jennifer

    2008-01-01

    Numerous anomalies involving the sex chromosomes (X or Y) have been documented and their impact on development, learning, and behavior studied. This article reviews three of these disorders, Turner syndrome, Klinefelter syndrome, and Lesch-Nyhan disease. Each of these three is associated with one or more selective impairments or behavioral…

  15. Seasonality of Congenital Anomalies in Europe

    NARCIS (Netherlands)

    Luteijn, Johannes Michiel; Dolk, Helen; Addor, Marie-Claude; Arriola, Larraitz; Barisic, Ingeborg; Bianchi, Fabrizio; Calzolari, Elisa; Draper, Elizabeth; Garne, Ester; Gatt, Miriam; Haeusler, Martin; Khoshnood, Babak; McDonnell, Bob; Nelen, Vera; O'Mahony, Mary; Mullaney, Carmel; Queisser-Luft, Annette; Rankin, Judith; Tucker, David; Verellen-Dumoulin, Christine; de Walle, Hermien; Yevtushok, Lyubov

    BackgroundThis study describes seasonality of congenital anomalies in Europe to provide a baseline against which to assess the impact of specific time varying exposures such as the H1N1 pandemic influenza, and to provide a comprehensive and recent picture of seasonality and its possible relation to

  16. Drug safety in pregnancy - monitoring congenital anomalies

    NARCIS (Netherlands)

    Morgan, Margery; De Jong-Van Den Berg, Lolkje T. W.; Jordan, Sue

    Aim This paper outlines research into the causes of congenital anomalies, and introduces a pan-European study. The potential roles of nurses and midwives in this area are illustrated by a case report. Background Since the thalidomide disaster, use of drugs in pregnancy has been carefully monitored

  17. Supercurrent anomalies in 4d SCFTs

    Science.gov (United States)

    Papadimitriou, Ioannis

    2017-07-01

    We use holographic renormalization of minimal N=2 gauged supergravity in order to derive the general form of the quantum Ward identities for 3d N=2 and 4d N=1 superconformal theories on general curved backgrounds, including an arbitrary fermionic source for the supercurrent. The Ward identities for 4d N=1 theories contain both bosonic and fermionic global anomalies, which we determine explicitly up to quadratic order in the supercurrent source. The Ward identities we derive apply to any superconformal theory, independently of whether it admits a holographic dual, except for the specific values of the a and c anomaly coefficients, which are equal due to our starting point of a two-derivative bulk supergravity theory. We show that the fermionic anomalies lead to an anomalous transformation of the supercurrent under rigid supersymmetry on backgrounds admitting Killing spinors, even if all superconformal anomalies are numerically zero on such backgrounds. The anomalous transformation of the supercurrent under rigid supersymmetry leads to an obstruction to the Q-exactness of the stress tensor in supersymmetric vacua, and may have implications for the applicability of localization techniques. We use this obstruction to the Q-exactness of the stress tensor, together with the Ward identities, in order to determine the general form of the stress tensor and R-current one-point functions in supersymmetric vacua, which allows us to obtain general expressions for the supersymmetric Casimir charges and partition function.

  18. Drug safety in pregnancy - monitoring congenital anomalies

    NARCIS (Netherlands)

    Morgan, Margery; De Jong-Van Den Berg, Lolkje T. W.; Jordan, Sue

    2011-01-01

    Aim This paper outlines research into the causes of congenital anomalies, and introduces a pan-European study. The potential roles of nurses and midwives in this area are illustrated by a case report. Background Since the thalidomide disaster, use of drugs in pregnancy has been carefully monitored t

  19. PROBLEMA ANOMALI DALAM INITIAL PUBLIC OFFERING (IPO

    Directory of Open Access Journals (Sweden)

    Sautma Ronni Basana

    2003-01-01

    Full Text Available This study on Initial Public Offerings (IPO showed that IPO stocks on average were underpriced, underperformed in the long run aftermarket and the Hot and Cold market cycle was present. These phenomenom can be explained by among others, the following: Asymetric Information, Winner's Curse, Traditional-Ibbotson, and Signalling Equilibrium Phenomenom. However, all of these can't give a satisfactory explanation because they were based on the price which existed on the secondary market (Underpriced Theory. The Withdrawn IPO (WIPO theory tried to explain the IPO anomaly differently so that the IPO anomaly could be explained clearly. Abstract in Bahasa Indonesia : Studi tentang Penawaran Saham Perdana (IPO menunjukkan saham-saham IPO secara rata-rata mengalami Underpriced, kinerja jangka panjang yang jelek dan adanya siklus pasar "Hot" dan "Cold". Ada beberapa penjelasan terhadap fenomena tersebut, antara lain: Informasi Asimetri, WinnerCurse, Tradisional-Ibbotson, Signaling Equilibrium Phenomenom tetapi semuanya belum memuaskan karena berdasarkan pada basis harga yang ada di pasar sekunder (Teori Underpriced. Teori Withdrawn IPO (WIPO mencoba menjelaskan fenomena anomali IPO dengan cara yang berbeda sehingga fenomena anomali IPO dapat dijelaskan secara tuntas. Kata kunci: Penawaran Saham Perdana (IPO, Underpriced, Withdrawn IPO (WIPO.

  20. Congenital cardiac anomalies in an English bulldog.

    Science.gov (United States)

    McConkey, Marina J

    2011-11-01

    A 4-year-old male castrated English bulldog was referred to the Atlantic Veterinary College for evaluation of exercise intolerance, multiple syncopal episodes, and a grade IV/VI heart murmur. The dog was shown to have 3 congenital cardiac anomalies: atrial septal defect, mitral valve dysplasia, and subaortic stenosis. Medical management consisted of exercise restriction, atenolol, pimobendan, and taurine.

  1. Intracardiac Eustachian Valve Cyst in an Adult Detected with Other Cardiac Anomalies: Usefulness of Multidetector CT in Diagnosis

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Hyung Ji; Jung, Jung Im; Kim, Hwan Wook; Lee, Kyo Young [Seoul St. Mary' s Hospital, College of Medicine, The Catholic University of Korea, Seoul (Korea, Republic of)

    2012-07-15

    We present an unusual case of an intracardiac Eustachian valve cyst observed concurrently with atresia of the coronary sinus ostium, a persistent left superior vena cava (LSVC) and a bicuspid aortic valve. There have been several echocardiographic reports of Eustachian valve cysts; however, there is no report of multidetector computed tomography (MDCT) findings related to a Eustachian valve cyst. Recently, we observed a Eustachian valve cyst diagnosed on MDCT showing a hypodense cyst at the characteristic location of the Eustachian valve (the junction of the right atrium and inferior vena cava). MDCT also demonstrated additional cardiovascular anomalies including atresia of the coronary sinus ostium and a persistent LSVC and bicuspid aortic valve.

  2. Josephson tunnel junctions with ferromagnetic interlayer

    Energy Technology Data Exchange (ETDEWEB)

    Weides, M.P.

    2006-07-01

    Superconductivity and ferromagnetism are well-known physical properties of solid states that have been widely studied and long thought about as antagonistic phenomena due to difference in spin ordering. It turns out that the combination of both superconductor and ferromagnet leads to a very rich and interesting physics. One particular example, the phase oscillations of the superconducting order parameter inside the ferromagnet, will play a major role for the devices discussed in this work. In this thesis, I present Josephson junctions with a thin Al{sub 2}O{sub 3} tunnel barrier and a ferromagnetic interlayer, i.e. superconductor-insulator-ferromagnet-superconductor (SIFS) stacks. The fabrication of junctions was optimized regarding the insulation of electrodes and the homogeneity of the current transport. The junctions were either in the 0 or {pi} coupled ground state, depending on the thickness of the ferromagnetic layer and on temperature. The influence of ferromagnetic layer thickness on the transport properties and the coupling (0, {pi}) of SIFS tunnel junctions was studied. Furthermore, using a stepped ferromagnetic layer with well-chosen thicknesses, I obtained the so-called 0-{pi} Josephson junction. At a certain temperature this 0-{pi} junction can be made perfectly symmetric. In this case the ground state corresponds to a vortex of supercurrent creating a magnetic flux which is a fraction of the magnetic flux quantum {phi}{sub 0}. Such structures allow to study the physics of fractional vortices and to build various electronic circuits based on them. The SIFS junctions presented here have an exponentially vanishing damping at T {yields} 0. The SIFS technology developed within the framework of this work may be used to construct classical and quantum devices such as oscillators, memory cells and qubits. (orig.)

  3. Model Building to Facilitate Understanding of Holliday Junction and Heteroduplex Formation, and Holliday Junction Resolution

    Science.gov (United States)

    Selvarajah, Geeta; Selvarajah, Susila

    2016-01-01

    Students frequently expressed difficulty in understanding the molecular mechanisms involved in chromosomal recombination. Therefore, we explored alternative methods for presenting the two concepts of the double-strand break model: Holliday junction and heteroduplex formation, and Holliday junction resolution. In addition to a lecture and…

  4. Increasing gap junctional coupling: a tool for dissecting the role of gap junctions

    DEFF Research Database (Denmark)

    Axelsen, Lene Nygaard; Haugan, Ketil; Stahlhut, Martin;

    2007-01-01

    . In a number of cases, gap junctions have been implicated in the initiation and progress of disease, and experimental uncoupling has been used to investigate the exact role of coupling. The inverse approach, i.e., to increase coupling, has become possible in recent years and represents a new way of testing......Much of our current knowledge about the physiological and pathophysiological role of gap junctions is based on experiments where coupling has been reduced by either chemical agents or genetic modification. This has brought evidence that gap junctions are important in many physiological processes...... the role of gap junctions. The aim of this review is to summarize the current knowledge obtained with agents that selectively increase gap junctional intercellular coupling. Two approaches will be reviewed: increasing coupling by the use of antiarrhythmic peptide and its synthetic analogs...

  5. Pure duplication of the distal long arm of chromosome 15 with ebstein anomaly and clavicular anomaly.

    Science.gov (United States)

    O'Connor, Rachel; Al-Murrani, Amel; Aftimos, Salim; Asquith, Philip; Mazzaschi, Roberto; Eyrolle-Guignot, Dominique; George, Alice M; Love, Donald R

    2011-01-01

    This report is of a patient with pure trisomy of 15q24-qter who presents with the rare Ebstein anomaly and a previously unreported skeletal anomaly. Chromosome microarray analysis allowed high-resolution identification of the extent of the trisomy and provided a means of achieving higher-resolution breakpoint data. The phenotypic expression of unbalanced chromosomal regions is a complex phenomenon, and fine mapping of the involved region, as described here, is only a first step on the path to its full understanding. Overexpression of the LINGO-1 and CSPG4 genes has been implicated in developmental delay seen in other patients with trisomy of 15q24-qter, but our patient is currently too young to ascertain developmental progress. The genetic underpinning of Ebstein anomaly and the skeletal anomaly reported here is unclear based on our high-resolution dosage mapping.

  6. Pure Duplication of the Distal Long Arm of Chromosome 15 with Ebstein Anomaly and Clavicular Anomaly

    Directory of Open Access Journals (Sweden)

    Rachel O'Connor

    2011-01-01

    Full Text Available This report is of a patient with pure trisomy of 15q24-qter who presents with the rare Ebstein anomaly and a previously unreported skeletal anomaly. Chromosome microarray analysis allowed high-resolution identification of the extent of the trisomy and provided a means of achieving higher-resolution breakpoint data. The phenotypic expression of unbalanced chromosomal regions is a complex phenomenon, and fine mapping of the involved region, as described here, is only a first step on the path to its full understanding. Overexpression of the LINGO-1 and CSPG4 genes has been implicated in developmental delay seen in other patients with trisomy of 15q24-qter, but our patient is currently too young to ascertain developmental progress. The genetic underpinning of Ebstein anomaly and the skeletal anomaly reported here is unclear based on our high-resolution dosage mapping.

  7. Chromosomal anomalies: The experience of the Congenital Anomalies Registry of the Valencia Region

    National Research Council Canada - National Science Library

    Gimeno-Martos, S; Cavero-Carbonell, C; López-Maside, A; Bosch-Sánchez, S; Martos-Jiménez, C; Zurriaga, O

    2016-01-01

    ...) in the Valencia Region, in less than one year olds, during the period 2007-2011. Live births, still births and termination of pregnancy due to foetal anomaly between 2007 and 2011 with chromosomal CA...

  8. Orbital debris hazard insights from spacecraft anomalies studies

    Science.gov (United States)

    McKnight, Darren S.

    2016-09-01

    Since the dawning of the space age space operators have been tallying spacecraft anomalies and failures then using these insights to improve the space systems and operations. As space systems improved and their lifetimes increased, the anomaly and failure modes have multiplied. Primary triggers for space anomalies and failures include design issues, space environmental effects, and satellite operations. Attempts to correlate anomalies to the orbital debris environment have started as early as the mid-1990's. Early attempts showed tens of anomalies correlated well to altitudes where the cataloged debris population was the highest. However, due to the complexity of tracing debris impacts to mission anomalies, these analyses were found to be insufficient to prove causation. After the fragmentation of the Chinese Feng-Yun satellite in 2007, it was hypothesized that the nontrackable fragments causing anomalies in LEO would have increased significantly from this event. As a result, debris-induced anomalies should have gone up measurably in the vicinity of this breakup. Again, the analysis provided some subtle evidence of debris-induced anomalies but it was not convincing. The continued difficulty in linking debris flux to satellite anomalies and failures prompted the creation of a series of spacecraft anomalies and failure workshops to investigate the identified shortfalls. These gatherings have produced insights into why this process is not straightforward. Summaries of these studies and workshops are presented and observations made about how to create solutions for anomaly attribution, especially as it relates to debris-induced spacecraft anomalies and failures.

  9. Pure Duplication of the Distal Long Arm of Chromosome 15 with Ebstein Anomaly and Clavicular Anomaly

    OpenAIRE

    Rachel O'Connor; Amel Al-Murrani; Salim Aftimos; Philip Asquith; Roberto Mazzaschi; Dominique Eyrolle-Guignot; George, Alice M.; Love, Donald R.

    2011-01-01

    This report is of a patient with pure trisomy of 15q24-qter who presents with the rare Ebstein anomaly and a previously unreported skeletal anomaly. Chromosome microarray analysis allowed high-resolution identification of the extent of the trisomy and provided a means of achieving higher-resolution breakpoint data. The phenotypic expression of unbalanced chromosomal regions is a complex phenomenon, and fine mapping of the involved region, as described here, is only a first step on the path to...

  10. Dislocation Multi-junctions and Strain Hardening

    Energy Technology Data Exchange (ETDEWEB)

    Bulatov, V; Hsiung, L; Tang, M; Arsenlis, A; Bartelt, M; Cai, W; Florando, J; Hiratani, M; Rhee, M; Hommes, G; Pierce, T; Diaz de la Rubia, T

    2006-06-20

    At the microscopic scale, the strength of a crystal derives from the motion, multiplication and interaction of distinctive line defects--dislocations. First theorized in 1934 to explain low magnitudes of crystal strength observed experimentally, the existence of dislocations was confirmed only two decades later. Much of the research in dislocation physics has since focused on dislocation interactions and their role in strain hardening: a common phenomenon in which continued deformation increases a crystal's strength. The existing theory relates strain hardening to pair-wise dislocation reactions in which two intersecting dislocations form junctions tying dislocations together. Here we report that interactions among three dislocations result in the formation of unusual elements of dislocation network topology, termed hereafter multi-junctions. The existence of multi-junctions is first predicted by Dislocation Dynamics (DD) and atomistic simulations and then confirmed by the transmission electron microscopy (TEM) experiments in single crystal molybdenum. In large-scale Dislocation Dynamics simulations, multi-junctions present very strong, nearly indestructible, obstacles to dislocation motion and furnish new sources for dislocation multiplication thereby playing an essential role in the evolution of dislocation microstructure and strength of deforming crystals. Simulation analyses conclude that multi-junctions are responsible for the strong orientation dependence of strain hardening in BCC crystals.

  11. Isostatic residual gravity anomaly data grid for the conterminous US

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The grid of isostatic residual gravity anomaly data was produced from the grid of Bouguer gravity anomaly data (see Bouguer gravity metadata) by using an...

  12. Radiological evaluation congenital gastrointestinal tract anomalies

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Young Hee; Kim, Ock [Hanil Hospital, Seoul (Korea, Republic of); Jang, Jung Wha [Seoul Nationl Hospital, Seoul (Korea, Republic of)

    1983-06-15

    With the improvements, during recent years, in the control of the infections and nutritional diseases the subject of congenital malformation becomes of increasing importance. The radiologic signs are crucial for prompt diagnosis of anomalies of alimentary tract and with early identification of resulting complication, surgical therapy is usually life-saving. 30 cases of congenital anomalies of alimentary tract in infants were reviewed in respect of age, sex, incidence and radiological findings. The results are summarized as follows; 1, The most common lesion was hypertrophic pyloric stenosis, followed by congenital megacolon and anorectal anomaly, tracheoesophageal fistula, intestinal atresia. 2. Male outnumbered female in most congenital anomalies of alimentary tract. 25 cases were under the age of 1 month. 3. Common symptoms of upper gastrointestinal tract obstruction are vomiting and abdominal distension. In the obstruction of lower gastrointestinal tract, abdominal distension and failure of meconium passage were noted. 4. Roentgenologic findings were as follows, a. Chest A-P and lateral view: In tracheoesophageal fistula, saccular dilatation of upper esophagus and displacement of trachea anterolaterally were the most common finding. b. Simple abdomen: Obstructive pattern of proximal portion of duodenum shows in 11 cases, of distal bowel shows in 16 cases. Duodenal atresia showed 'double bubble' sign, hypertrophic pyloric stenosis showed marked gastric distension, paucity of air in small bowel and increases gastric peristalsis were the most common findings. Hirschsprung's disease showed absenced of rectal gas almostly. The variable length between blind hindgut to anus was seen in anorectal anomalies. c. Esophagogram: Blind sac of upper esophagus was seen at the 4th thoracic spinal level and displacement of trachea anterolaterally. 1 case of tracheoesophageal fistula had an intact esophageal lumen. d. Upper G-I series: In hypertrophic pyloric

  13. Created-by-current states in long Josephson junctions

    Science.gov (United States)

    Boyadjiev, T. L.; Andreeva, O. Yu.; Semerdjieva, E. G.; Shukrinov, Yu. M.

    2008-08-01

    Critical curves "critical current-external magnetic field" of long Josephson junctions with inhomogeneity and variable width are studied. We demonstrate the existence of regions of magnetic field where some fluxon states are stable only if the external current through the junction is different from zero. Position and size of such regions depend on the length of the junction, its geometry, parameters of inhomogeneity and form of the junction. The noncentral (left and right) pure fluxon states appear in the inhomogeneous Josephson junction with the increase in the junction length. We demonstrate new bifurcation points with change in width of the inhomogeneity and amplitude of the Josephson current through the inhomogeneity.

  14. Thermionic refrigeration at CNT-CNT junctions

    Science.gov (United States)

    Li, C.; Pipe, K. P.

    2016-10-01

    Monte Carlo (MC) simulation is used to study carrier energy relaxation following thermionic emission at the junction of two van der Waals bonded single-walled carbon nanotubes (SWCNTs). An energy-dependent transmission probability gives rise to energy filtering at the junction, which is predicted to increase the average electron transport energy by as much as 0.115 eV, leading to an effective Seebeck coefficient of 386 μV/K. MC results predict a long energy relaxation length (˜8 μm) for hot electrons crossing the junction into the barrier SWCNT. For SWCNTs of optimal length, an analytical transport model is used to show that thermionic cooling can outweigh parasitic heat conduction due to high SWCNT thermal conductivity, leading to a significant cooling capacity (2.4 × 106 W/cm2).

  15. Silicon fiber with p-n junction

    Energy Technology Data Exchange (ETDEWEB)

    Homa, D.; Cito, A.; Pickrell, G.; Hill, C.; Scott, B. [Department of Materials Science and Engineering, Virginia Polytechnic Institute and State University, 312 Holden Hall, Blacksburg, Virginia 24060 (United States)

    2014-09-22

    In this study, we fabricated a p-n junction in a fiber with a phosphorous doped silicon core and fused silica cladding. The fibers were fabricated via a hybrid process of the core-suction and melt-draw techniques and maintained overall diameters ranging from 200 to 900 μm and core diameters of 20–800 μm. The p-n junction was formed by doping the fiber with boron and confirmed via the current-voltage characteristic. The demonstration of a p-n junction in a melt-drawn silicon core fiber paves the way for the seamless integration of optical and electronic devices in fibers.

  16. Vortex structures in exponentially shaped Josephson junctions

    Science.gov (United States)

    Shukrinov, Yu. M.; Semerdjieva, E. G.; Boyadjiev, T. L.

    2005-04-01

    We report the numerical calculations of the static vortex structure and critical curves in exponentially shaped long Josephson junctions for in-line and overlap geometries. Stability of the static solutions is investigated by checking the sign of the smallest eigenvalue of the associated Sturm-Liouville problem. The change in the junction width leads to the renormalization of the magnetic flux in comparison with the case of a linear one-dimensional model. We study the influence of the model's parameters, and particularly, the shape parameter on the stability of the states of the magnetic flux. We compare the vortex structure and critical curves for the in-line and overlap geometries. Our numerically constructed critical curve of the Josephson junction matches well with the experimental one.

  17. Holographic Josephson Junction from Massive Gravity

    CERN Document Server

    Hu, Ya-Peng; Zeng, Hua-Bi; Zhang, Hai-Qing

    2015-01-01

    We study the holographic superconductor-normal metal-superconductor (SNS) Josephon junction in the massive gravity. In the homogeneous case of the chemical potential, we find that the graviton mass will make the normal metal-superconductor phase transition harder to take place. In the holographic model of Josephson junction, it is found that the maximal tunneling current will decrease according to the graviton mass. Besides, the coherence length of the junction decreases as well with respect to the graviton mass. If one interprets the graviton mass as the effect of momentum dissipation in the boundary field theory, it indicates that the stronger the momentum dissipation is, the smaller the coherence length is.

  18. Characterization of magnetic tunnel junction test pads

    DEFF Research Database (Denmark)

    Østerberg, Frederik Westergaard; Kjær, Daniel; Nielsen, Peter Folmer

    2015-01-01

    We show experimentally as well as theoretically that patterned magnetic tunnel junctions can be characterized using the current-in-plane tunneling (CIPT) method, and the key parameters, the resistance-area product (RA) and the tunnel magnetoresistance (TMR), can be determined. The CIPT method...... on square tunnel junction pads with varying sizes and analyze the measured data using both the original and the modified CIPT model. Thus, we determine in which sample size range the modified CIPT model is needed to ensure validity of the extracted sample parameters, RA and TMR. In addition, measurements...... as a function of position on a square tunnel junction pad are used to investigate the sensitivity of the measurement results to probe misalignment....

  19. Gap junction diseases of the skin.

    Science.gov (United States)

    van Steensel, M A M

    2004-11-15

    Gap junctions are intercellular channels that allow the passage of water, ions, and small molecules. They are involved in quick, short-range messaging between cells and are found in skin, nervous tissue, heart, and muscle. An increasing number of hereditary skin disorders appear to be caused by mutations in one of the genes coding for the constituent proteins of gap junctions, known as connexins. In this review, the currently known connexin disorders that feature skin abnormalities are described: keratitis-ichthyosis deafness syndrome, erythrokeratoderma variabilis, Vohwinkel's syndrome, and a novel disorder called hypotrichosis-deafness syndrome. What is known about the pathogenesis of these disorders is discussed and related to gap junction physiology. (c) 2004 Wiley-Liss, Inc.

  20. Overdamped Josephson junctions for digital applications

    Energy Technology Data Exchange (ETDEWEB)

    Febvre, P., E-mail: Pascal.Febvre@univ-savoie.fr [University of Savoie, IMEP-LAHC – CNRS UMR5130, 73376 Le Bourget du Lac (France); De Leo, N.; Fretto, M.; Sosso, A. [I.N.Ri.M., Istituto Nazionale di Ricerca Metrologica, Strada delle Cacce 91, 10135 Torino (Italy); Belogolovskii, M. [Donetsk Institute for Physics and Engineering, 72 R. Luxemburg str., 83114 Donetsk (Ukraine); Collot, R. [University of Savoie, IMEP-LAHC – CNRS UMR5130, 73376 Le Bourget du Lac (France); Lacquaniti, V. [I.N.Ri.M., Istituto Nazionale di Ricerca Metrologica, Strada delle Cacce 91, 10135 Torino (Italy)

    2013-01-15

    Highlights: ► Properties of self-shunted sub-micron Nb/Al–AlO{sub x}/Nb SNIS junctions are studied. ► 1–100 kA/cm{sup 2} current densities and 0.1–0.7 mV critical voltages are obtained. ► The critical voltage-vs-temperature behavior of SNIS junctions is discussed. ► Numerical results showing an effect of the aluminum film thickness are presented. ► A Josephson balanced comparator is studied for different temperatures of operation. -- Abstract: An interesting feature of Superconductor–Normal metal–Superconductor Josephson junctions for digital applications is due to their non-hysteretic current–voltage characteristics in a broad temperature range below T{sub c}. This allows to design Single-Flux-Quantum (SFQ) cells without the need of external shunts. Two advantages can be drawn from this property: first the SFQ cells can be more compact which leads to a more integrated solution towards nano-devices and more complex circuits; second the absence of electrical parasitic elements associated with the wiring of resistors external to the Josephson junctions increases the performance of SFQ circuits, in particular regarding the ultimate speed of operation. For this purpose Superconductor–Normal metal–Insulator–Superconductor Nb/Al–AlO{sub x}/Nb Josephson junctions have been recently developed at INRiM with aluminum layer thicknesses between 30 and 100 nm. They exhibit non-hysteretic current–voltage characteristics with I{sub c}R{sub n} values higher than 0.5 mV in a broad temperature range and optimal Stewart McCumber parameters at 4.2 K for RSFQ applications. The main features of obtained SNIS junctions regarding digital applications are presented.

  1. A critical appraisal of the LSND anomaly

    CERN Document Server

    Boyko, I

    2008-01-01

    The so-called 'LSND anomaly', a 3.8 sigma excess of anti-nu_e events interpreted as originating from anti-nu_mu -> anti-nu_e oscillation, gave rise to many theoretical speculations. The MiniBooNE Collaboration reported inconsistency of this interpretation with the findings from their search for nu_mu -> nu_e oscillations. Yet the origin of the LSND anomaly was never clarified. A critical issue is the prediction of the background anti-nu_e flux that was used in the analysis of the LSND experiment. For this, decisive input comes from pion spectra measured with the HARP large-angle spectrometer under conditions that closely resemble the LSND situation: a proton beam with 800 MeV kinetic energy hitting a water target.

  2. Conformal anomaly around the sudden singularity

    CERN Document Server

    Houndjo, S J M

    2010-01-01

    Quantum effects due to particle creation on a classical sudden singularity have been investigated in a previous work. The conclusion was that quantum effects do not lead to the avoidance nor the modification of the sudden future singularity. In this paper, we investigate quantum corrections coming from conformal anomaly near the sudden future singularity. We conclude that when the equation of state is chosen to be $p=-\\rho-A\\rho^\\alpha$, the conformal anomaly can transform the sudden singularity in the singularity of type III for any $\\alpha> 1/2$ and in the singularity of the type I (the big rip) or the big crunch for $1/2<\\alpha<3/2$.

  3. Conformal anomaly around the sudden singularity

    Science.gov (United States)

    Houndjo, S. J. M.

    2010-10-01

    Quantum effects due to particle creation on a classical sudden singularity have been investigated in a previous work. The conclusion was that quantum effects do not lead to the avoidance nor the modification of the sudden future singularity. In this paper, we investigate quantum corrections coming from conformal anomaly near the sudden future singularity. We conclude that when the equation of state is chosen to be p=-ρ-Aρα, the conformal anomaly can transform the sudden singularity into the singularity of type III for any α>1/2 and into the singularity of the type I (the big rip) or the big crunch for 1/2<α<3/2.

  4. The GSI Time Anomaly: Facts and Fiction

    Energy Technology Data Exchange (ETDEWEB)

    Giunti, Carlo [INFN, Sezione di Torino, Via P. Giuria 1, I-10125 Torino (Italy)

    2009-03-15

    The claims that the GSI time anomaly is due to the mixing of neutrinos in the final state of the observed electron-capture processes are refuted. With the help of an analogy with a double-slit experiment, it is shown that the standard method of calculation of the rate of an interaction process by adding the rates of production of all the allowed final states, regardless of a possible coherence among them, is correct. It is a consequence of causality. It is shown that the GSI time anomaly may be caused by quantum beats due to the existence of two coherent energy levels of the decaying ion with an extremely small energy splitting (about 6x10{sup -16} eV) and relative probabilities having a ratio of about 1/99.

  5. LHCb anomalies from a natural perspective

    CERN Document Server

    García García, Isabel

    2016-01-01

    Tension between the Standard Model (SM) and data concerning $b \\rightarrow s$ processes has become apparent. Most notoriously, concerning the $R_K$ ratio, which probes lepton non-universality in $b$ decays, and measurements involving the decays $B \\rightarrow K^* \\mu^+ \\mu^-$ and $B_s \\rightarrow \\phi \\mu^+ \\mu^-$. Careful analysis of a wide range of $b \\rightarrow s$ data shows that certain kinds of new physics can significantly ameliorate agreement with experiment. Here, we show that these $b \\rightarrow s$ anomalies can be naturally accommodated in the context of Natural Scherk-Schwarz Theories of the Weak Scale -- a class of models designed to address the hierarchy problem. No extra states need to be introduced in order to accommodate these anomalies, and the assumptions required regarding flavor violating couplings are very mild. Moreover, the structure of the theory makes sharp predictions regarding $B$ meson decays into final states including $\\tau^+ \\tau^-$ pairs, which will provide a future test of t...

  6. Do retractile testes have anatomical anomalies?

    Science.gov (United States)

    Anderson, Kleber M.; Costa, Suelen F.; Sampaio, Francisco J.B.; Favorito, Luciano A.

    2016-01-01

    ABSTRACT Objectives: To assess the incidence of anatomical anomalies in patients with retractile testis. Materials and Methods: We studied prospectively 20 patients (28 testes) with truly retractile testis and compared them with 25 human fetuses (50 testes) with testis in scrotal position. We analyzed the relations among the testis, epididymis and patency of the processus vaginalis (PV). To analyze the relations between the testis and epididymis, we used a previous classification according to epididymis attachment to the testis and the presence of epididymis atresia. To analyze the structure of the PV, we considered two situations: obliteration of the PV and patency of the PV. We used the Chi-square test for contingency analysis of the populations under study (p patent processus vaginalis and epididymal anomalies. PMID:27564294

  7. Coronary artery anomalies in Turner Syndrome

    DEFF Research Database (Denmark)

    Viuff, Mette H; Trolle, Christian; Wen, Jan;

    2016-01-01

    BACKGROUND: Congenital heart disease, primarily involving the left-sided structures, is often seen in patients with Turner Syndrome. Moreover, a few case reports have indicated that coronary anomalies may be more prevalent in Turner Syndrome than in the normal population. We therefore set out...... to systematically investigate coronary arterial anatomy by computed tomographic coronary angiography (coronary CTA) in Turner Syndrome patients. METHODS: Fifty consecutive women with Turner Syndrome (mean age 47 years [17-71]) underwent coronary CTA. Patients were compared with 25 gender-matched controls. RESULTS......: Coronary anomaly was more frequent in patients with Turner Syndrome than in healthy controls [20% vs. 4% (p = 0.043)]. Nine out of ten abnormal cases had an anomalous left coronary artery anatomy (absent left main trunk, n = 7; circumflex artery originating from the right aortic sinus, n = 2). One case had...

  8. Network Anomaly Detection Based on Wavelet Analysis

    Directory of Open Access Journals (Sweden)

    Ali A. Ghorbani

    2008-11-01

    Full Text Available Signal processing techniques have been applied recently for analyzing and detecting network anomalies due to their potential to find novel or unknown intrusions. In this paper, we propose a new network signal modelling technique for detecting network anomalies, combining the wavelet approximation and system identification theory. In order to characterize network traffic behaviors, we present fifteen features and use them as the input signals in our system. We then evaluate our approach with the 1999 DARPA intrusion detection dataset and conduct a comprehensive analysis of the intrusions in the dataset. Evaluation results show that the approach achieves high-detection rates in terms of both attack instances and attack types. Furthermore, we conduct a full day's evaluation in a real large-scale WiFi ISP network where five attack types are successfully detected from over 30 millions flows.

  9. Neutrino Anomalies in an Extended Zee Model

    CERN Document Server

    Joshipura, A S; Joshipura, Anjan S.; Rindani, Saurabh D.

    1999-01-01

    We discuss an extended SU(2)X U(1) model which naturally leads to mass scales and mixing angles relevant for understanding both the solar and atmospheric neutrino anomalies. No right-handed neutrinos are introduced in the model.The model uses a softly broken L_e-L_{\\mu}-L_{\\tau} symmetry. Neutrino masses arise only at the loop level. The one-loop neutrino masses which arise as in the Zee model solve the atmospheric neutrino anomaly while breaking of L_e-L_{\\mu}-L_{\\tau} generates at two-loop order a mass splitting needed for the vacuum solution of the solar neutrino problem. A somewhat different model is possible which accommodates the large-angle MSW resolution of the solar neutrino problem.

  10. Axial Vector $Z'$ and Anomaly Cancellation

    CERN Document Server

    Ismail, Ahmed; Tsao, Kuo-Hsing; Unwin, James

    2016-01-01

    Whilst the prospect of new $Z'$ gauge bosons with only axial couplings to the Standard Model (SM) fermions is widely discussed, examples of anomaly-free renormalisable models are lacking in the literature. We look to remedy this by constructing several motivated examples. Specifically, we consider axial vectors which couple universally to all SM fermions, as well as those which are generation-specific, leptophilic, and leptophobic. Anomaly cancellation typically requires the presence of new coloured and charged chiral fermions, and we argue that the masses of these new states must generally be comparable to that of the axial vector. Finally, an axial vector mediator could provide a portal between SM and hidden sector states, and we also consider the possibility that the axial vector couples to dark matter. If the dark matter relic density is set due to freeze-out via the axial vector, this strongly constrains the parameter space.

  11. Footprints of New Strong Dynamics via Anomaly

    CERN Document Server

    Nakai, Yuichiro; Tobioka, Kohsaku

    2015-01-01

    Chiral anomaly provides a smoking-gun evidence of a new confining gauge theory. Motivated by a reported event excess in diphoton invariant mass distribution at the LHC, we discuss a scenario that a pseudo-Nambu-Goldstone (pNG) boson of a new QCD-like theory is produced by gluon fusion and decays into a pair of the standard model gauge bosons. Despite the strong dynamics, the production cross section and the decay widths are determined by anomaly matching condition. The excess can be explained by the pNG boson with mass of around 750 GeV. The model also predicts exotic hadrons such as a color octet scalar and baryons which are within the reach of the LHC experiment.

  12. Axial vector Z‧ and anomaly cancellation

    Science.gov (United States)

    Ismail, Ahmed; Keung, Wai-Yee; Tsao, Kuo-Hsing; Unwin, James

    2017-05-01

    Whilst the prospect of new Z‧ gauge bosons with only axial couplings to the Standard Model (SM) fermions is widely discussed, examples of anomaly-free renormalisable models are lacking in the literature. We look to remedy this by constructing several motivated examples. Specifically, we consider axial vectors which couple universally to all SM fermions, as well as those which are generation-specific, leptophilic, and leptophobic. Anomaly cancellation typically requires the presence of new coloured and charged chiral fermions, and we argue that in a large class of models masses of these new states are expected to be comparable to that of the axial vector. Finally, an axial vector mediator could provide a portal between SM and hidden sector states, and we also consider the possibility that the axial vector couples to dark matter. If the dark matter relic density is set due to freeze-out via the axial vector, this strongly constrains the parameter space.

  13. Spectrum of congenital anomalies in pregnancies with pregestational diabetes

    NARCIS (Netherlands)

    Garne, Ester; Loane, Maria; Dolk, Helen; Barisic, Ingeborg; Addor, Marie-Claude; Arriola, Larraitz; Bakker, Marian; Calzolari, Elisa; Dias, Carlos Matias; Doray, Berenice; Gatt, Miriam; Melve, Kari Klyungsoyr; Nelen, Vera; O'Mahony, Mary; Pierini, Anna; Randrianaivo-Ranjatoelina, Hanitra; Rankin, Judith; Rissmann, Anke; Tucker, David; Verellun-Dumoulin, Christine; Wiesel, Awi

    2012-01-01

    BACKGROUND Maternal pregestational diabetes is a well-known risk factor for congenital anomalies. This study analyses the spectrum of congenital anomalies associated with maternal diabetes using data from a large European database for the population-based surveillance of congenital anomalies. METHOD

  14. Morning glory disc anomaly with Chiari type I malformation.

    Science.gov (United States)

    Arlow, Tim; Arepalli, Sruthi; Flanders, Adam E; Shields, Carol L

    2014-04-30

    Morning glory disc anomaly is a rare optic nerve dysplasia associated with various neovascular abnormalities. Due to these associations, children with morning glory disc anomaly have brain imaging and angiography to detect other congenital defects. The authors report the case of an infant with morning glory disc anomaly and coexisting Chiari type I malformation.

  15. Spectrum of congenital anomalies in pregnancies with pregestational diabetes

    DEFF Research Database (Denmark)

    Garne, Ester; Loane, Maria; Dolk, Helen;

    2012-01-01

    Maternal pregestational diabetes is a well-known risk factor for congenital anomalies. This study analyses the spectrum of congenital anomalies associated with maternal diabetes using data from a large European database for the population-based surveillance of congenital anomalies....

  16. Minor Physical Anomalies, Footprints, and Behavior: Was the Buddha Right?

    Science.gov (United States)

    Draper, Thomas W.; Munoz, Milagros M.

    1982-01-01

    A relationship between an anomaly of the footprint suggested by ancient Abhidhamma meditations and Minor Physical Anomalies Scale was observed in children. The footprint anomalies correlated with the activity levels of children in the same way as the scores on the scale and consistently with prior research using the scale. (Author/RD)

  17. Multiplication in Silicon p-n Junctions

    DEFF Research Database (Denmark)

    Moll, John L.

    1965-01-01

    Multiplication values were measured in the collector junctions of silicon p-n-p and n-p-n transistors before and after bombardment by 1016 neutrons/cm2. Within experimental error there was no change either in junction fields, as deduced from capacitance measurements, or in multiplication values...... in any of the transistors. The implication is that the electron and hole ionization rates did not change as a result of the addition of extra scattering centers. This result is in direct contradiction to observations of Lee et al. The most likely explanation for the discrepancy is erroneous determination...

  18. Fast transient response of novel Peltier junctions

    Energy Technology Data Exchange (ETDEWEB)

    Hoyos, G.E.; Rao, K.R.; Jerger, D.

    1977-01-01

    The fast transient response of a thermoelectric (TE) cooler with novel geometry is discussed. This geometry involves conical semiconductor legs whose hot to cold junction cross-sectional area ratios can be varied. The novel TE junctions are fabricated such that the thermal capacitance and electrical conductance are decreased while simultaneously increasing the thermal resistance. The experimental apparatus which includes the vacuum system, power supplies, pulse and control circuitry, sensing and measuring instrumentation etc. is described. With narrow pulse width and large amplitudes, additional cooling of the order of 45/sup 0/C below the steady-state maximum with recovery times in the range of 1 to 3 sec is obtained.

  19. The Geometric Field at a Josephson Junction

    CERN Document Server

    Atanasov, Victor

    2016-01-01

    A geometric potential from the kinetic term of a constrained to a curved hyper-plane of space-time quantum superconducting condensate is derived. An energy conservation relation involving the geometric field at every material point in the superconductor is demonstrated. At a Josephson junction the energy conservation relation implies the possibility to transform electric energy into geometric field energy, that is curvature of space-time. Experimental procedures to verify that the Josephson junction can act as a voltage-to-curvature converter are discussed.

  20. Microscopic tunneling theory of long Josephson junctions

    DEFF Research Database (Denmark)

    Grønbech-Jensen, N.; Hattel, Søren A.; Samuelsen, Mogens Rugholm

    1992-01-01

    We present a numerical scheme for solving a nonlinear partial integro-differential equation with nonlocal time dependence. The equation describes the dynamics in a long Josephson junction modeled by use of the microscopic theory for tunneling between superconductors. We demonstrate that the detai......We present a numerical scheme for solving a nonlinear partial integro-differential equation with nonlocal time dependence. The equation describes the dynamics in a long Josephson junction modeled by use of the microscopic theory for tunneling between superconductors. We demonstrate...

  1. Rectangular-to-circular groove waveguide junction

    Institute of Scientific and Technical Information of China (English)

    CUI; Licheng; (崔立成); YANG; Hongsheng; (杨鸿生)

    2003-01-01

    Mode matching method is used to analyze the scattering characteristics of the rectangular-to-circular groove waveguide junction. Firstly, the scattering matrix equation is obtained by matching the electromagnetic fields at the boundary of the junction. The scattering coefficients can be obtained from the equation. Secondly the scattering characteristics of the iris with rectangular window positioned in circular groove waveguide are briefly analyzed. Thirdly, the convergent problem is discussed and the numerical results are given. At last experiment is made and good agreement is found between the calculated results and the measured results.

  2. Electroplated Ni on the PN Junction Semiconductor

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jin Joo; Uhm, Young Rang; Son, Kwang Jae; Kim, Jong Bum; Choi, Sang Moo; Park, Jong Han; Hong, Jintae [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-05-15

    Nickel (Ni) electroplating was implemented by using a metal Ni powder in order to establish a Ni-63 plating condition on the PN junction semiconductor needed for production of betavoltaic battery. PN junction semiconductors with a Ni seed layer of 500 and 1000 A were coated with Ni at current density from 10 to 50 mA cm{sup 2}. The surface roughness and average grain size of Ni deposits were investigated by XRD and SEM techniques. The roughness of Ni deposit was increased as the current density was increased, and decreased as the thickness of Ni seed layer was increased.

  3. Cosmological anomalies and exotic smoothness structures

    OpenAIRE

    Asselmeyer-Maluga, Torsten; Brans, Carl H.

    2001-01-01

    It seems to be generally accepted that apparently anomalous cosmological observations, such as accelerating expansion, etc., necessarily are inconsistent with standard general relativity and standard matter sources. Following the suggestions of S{\\l}adkowski, we point out that in addition to exotic theories and exotic matter there is another possibility. We refer to exotic differential structures on ${\\mathbb R}^4$ which could be the source of the observed anomalies without changing the Einst...

  4. Horseshoe Appendix: An Extremely Rare Appendiceal Anomaly.

    Science.gov (United States)

    Singh, Ch Gyan; Nyuwi, Kuotho T; Rangaswamy, Raju; Ezung, Yibenthung S; Singh, H Manihar

    2016-03-01

    Appendiceal anomalies are extremely rare malformations that are usually found incidentally. Agenesis and duplication of the appendix has been well documented however, the cases of horseshoe appendix reported is very limited, only four cases reported so far. Here, we report a four and half-year-old who underwent interval appendectomy. Intraoperatively both the ends of the appendix were found to be communicating with the cecum with two separate base or stump located at a sagital disposal- the so called "horseshoe appendix".

  5. Resolution of the solar neutrino anomaly

    CERN Document Server

    Dubin, M; Dubin, Maurice; Soberman, Robert K

    1996-01-01

    The solar neutrino anomaly, measurements discrepant from predictions of the Standard Solar Model, has existed for over 30 years. Multiple experiments measuring fluxes from several reactions in the hydrogen fusion chain have added to the puzzle. Each of the several elements of the enigma are resolved by recognition of measurements establishing that most of the sun's fusion must occur near the surface rather than the core.

  6. Magnetic Anomaly Detection by Remote Means

    Science.gov (United States)

    2016-09-21

    effort we have demonstrated the detection of Xe using the remote Radar REMPI technique and the excitation of Xe atoms remotely using UV laser pulses...unlimited. 13. SUPPLEMENTARY NOTES 14. ABSTRACT Research on the possibility of detecting magnetic anomalies remotely using laser excitation of a... using laser excitation of a naturally occurring atomic or molecular species in air has focused on the use of Xe129. Although Xe129 is only present in

  7. Casimir Effect, Hawking Radiation and Trace Anomaly

    CERN Document Server

    Setare, M R

    2001-01-01

    The Casimir energy for massless scalar field of two parallel conductor, in two dimensional Schwarzchild black hole background, with Dirichlet boundary conditions is calculated by making use of general properties of renormalized stress tensor. We show that vacuum expectation value of stress tensor can be obtain by Casimir effect, trace anomaly and Hawking radiation. Four-dimensional of this problem, by this method, is under progress by this author.

  8. Electromagnetic duality anomaly in curved spacetimes

    CERN Document Server

    Agullo, I; Navarro-Salas, J

    2016-01-01

    The source-free Maxwell action is invariant under electric-magnetic duality rotations in arbitrary spacetimes. This leads to a conserved classical Noether charge. We show that this conservation law is broken at the quantum level in presence of a background classical gravitational field with a non-trivial Chern-Pontryagin invariant, in a parallel way to the chiral anomaly for massless Dirac fermions. Among the physical consequences, the net polarization of the quantum electromagnetic field is not conserved.

  9. Anomaly induced effects in a magnetic field

    OpenAIRE

    Antoniadis, Ignatios; Boyarsky, Alexey; Ruchayskiy, Oleg

    2007-01-01

    We consider a modification of electrodynamics by an additional light massive vector field, interacting with the photon via Chern-Simons-like coupling. This theory predicts observable effects for the experiments studying the propagation of light in an external magnetic field, very similar to those, predicted by theories of axion and axion-like particles. We discuss a possible microscopic origin of this theory from a theory with non-trivial gauge anomaly cancellation between massive and light p...

  10. OPAD data analysis. [Optical Plumes Anomaly Detection

    Science.gov (United States)

    Buntine, Wray L.; Kraft, Richard; Whitaker, Kevin; Cooper, Anita E.; Powers, W. T.; Wallace, Tim L.

    1993-01-01

    Data obtained in the framework of an Optical Plume Anomaly Detection (OPAD) program intended to create a rocket engine health monitor based on spectrometric detections of anomalous atomic and molecular species in the exhaust plume are analyzed. The major results include techniques for handling data noise, methods for registration of spectra to wavelength, and a simple automatic process for estimating the metallic component of a spectrum.

  11. Unsupervised Topic Discovery by Anomaly Detection

    Science.gov (United States)

    2013-09-01

    anomalous. 7 c. Support Vector Machines SVM was first introduced by Cortes and Vapnik [9], and it was used to detect anomalies in a single class...into a single file to be consumed by the LDA program. 2. Whitepaper posted on Facebook The population whitepaper posted on Facebook talks about...It talks about the importance of marriage and parenthood and the measures taken by the government to encourage parenthood . It addresses unpopular

  12. Dispersive Approach to the Trace Anomaly

    OpenAIRE

    Kawka, N.; Teryaev, O. V.; Veretin, O.L.

    1997-01-01

    In the scalar $\\phi^4$ field model the dispersive approach to the trace anomaly is proposed. It is shown that it is impossible to get dispersion representation for all formfactors so that preserve both the translation and dilatation Ward identities. Subtractions which preserve energy-momentum conservation violate the classical trace Ward--Takahashi identity and give rise to an anomalous contribution to the matrix element of stress tensor $\\theta_\\mu^\

  13. Reasoning Anomalies Associated With Delusions in Schizophrenia

    OpenAIRE

    Langdon, Robyn; Ward, Philip B.; Coltheart, Max

    2008-01-01

    Deluded people differ from nondeluded controls on attributional style questionnaires and probabilistic-reasoning and theory-of-mind (ToM) tasks. No study to date has examined the relations between these 3 reasoning anomalies in the same individuals so as to evaluate their functional independence and potentially inform theories of delusion formation. We did so in 35 schizophrenic patients with a history of delusions, 30 of whom were currently deluded, and 34 healthy controls. Compared with hea...

  14. Anomaly Detection and Attribution Using Bayesian Networks

    Science.gov (United States)

    2014-06-01

    UNCLASSIFIED Anomaly Detection and Attribution Using Bayesian Networks Andrew Kirk, Jonathan Legg and Edwin El-Mahassni National Security and...detection in Bayesian networks , en- abling both the detection and explanation of anomalous cases in a dataset. By exploiting the structure of a... Bayesian network , our algorithm is able to efficiently search for local maxima of data conflict between closely related vari- ables. Benchmark tests using

  15. Common features of a vortex structure in long exponentially shaped Josephson junctions and Josephson junctions with inhomogeneities

    Science.gov (United States)

    Boyadjiev, T. L.; Semerdjieva, E. G.; Shukrinov, Yu. M.

    2007-09-01

    We study the vortex structure in three different models of the long Josephson junction: the exponentially shaped Josephson junction and the Josephson junctions with the resistor and the shunt inhomogeneities in the barrier layer. For these three models the critical curves “critical current-magnetic field” are numerically constructed. We develop the idea of the equivalence of the exponentially shaped Josephson junction and the rectangular junction with the distributed inhomogeneity and demonstrate that at some parameters of the shunt and the resistor inhomogeneities in the ends of the junction the corresponding critical curves are very close to the exponentially shaped one.

  16. Common features of a vortex structure in long exponentially shaped Josephson junctions and Josephson junctions with inhomogeneities

    Energy Technology Data Exchange (ETDEWEB)

    Boyadjiev, T.L. [Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation); Semerdjieva, E.G. [Plovdiv University, 24 Tzar Asen Str., Plovdiv 4000 (Bulgaria); Shukrinov, Yu.M. [Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation)], E-mail: shukrinv@theor.jinr.ru

    2007-09-01

    We study the vortex structure in three different models of the long Josephson junction: the exponentially shaped Josephson junction and the Josephson junctions with the resistor and the shunt inhomogeneities in the barrier layer. For these three models the critical curves 'critical current-magnetic field' are numerically constructed. We develop the idea of the equivalence of the exponentially shaped Josephson junction and the rectangular junction with the distributed inhomogeneity and demonstrate that at some parameters of the shunt and the resistor inhomogeneities in the ends of the junction the corresponding critical curves are very close to the exponentially shaped one.

  17. Thermal expansion anomaly regulated by entropy.

    Science.gov (United States)

    Liu, Zi-Kui; Wang, Yi; Shang, ShunLi

    2014-11-13

    Thermal expansion, defined as the temperature dependence of volume under constant pressure, is a common phenomenon in nature and originates from anharmonic lattice dynamics. However, it has been poorly understood how thermal expansion can show anomalies such as colossal positive, zero, or negative thermal expansion (CPTE, ZTE, or NTE), especially in quantitative terms. Here we show that changes in configurational entropy due to metastable micro(scopic)states can lead to quantitative prediction of these anomalies. We integrate the Maxwell relation, statistic mechanics, and first-principles calculations to demonstrate that when the entropy is increased by pressure, NTE occurs such as in Invar alloy (Fe3Pt, for example), silicon, ice, and water, and when the entropy is decreased dramatically by pressure, CPTE is expected such as in anti-Invar cerium, ice and water. Our findings provide a theoretic framework to understand and predict a broad range of anomalies in nature in addition to thermal expansion, which may include gigantic electrocaloric and electromechanical responses, anomalously reduced thermal conductivity, and spin distributions.

  18. Congenital anomalies and proximity to landfill sites.

    LENUS (Irish Health Repository)

    Boyle, E

    2004-01-01

    The occurrence of congenital anomalies in proximity to municipal landfill sites in the Eastern Region (counties Dublin, Kildare, Wicklow) was examined by small area (district electoral division), distance and clustering tendancies in relation to 83 landfills, five of which were major sites. The study included 2136 cases of congenital anomaly, 37,487 births and 1423 controls between 1986 and 1990. For the more populous areas of the region 50% of the population lived within 2-3 km of a landfill and within 4-5 km for more rural areas. In the area-level analysis, the standardised prevalence ratios, empirical and full Bayesian modelling, and Kulldorff\\'s spatial scan statistic found no association between the residential area of cases and location of landfills. In the case control analysis, the mean distance of cases and controls from the nearest landfill was similar. The odds ratios of cases compared to controls for increasing distances from all landfills and major landfills showed no significant difference from the baseline value of 1. The kernel and K methods showed no tendency of cases to cluster in relationship to landfills. In conclusion, congenital anomalies were not found to occur more commonly in proximity to municipal landfills.

  19. Conformal anomaly of super Wilson loop

    Energy Technology Data Exchange (ETDEWEB)

    Belitsky, A.V., E-mail: andrei.belitsky@asu.edu [Department of Physics, Arizona State University, Tempe, AZ 85287-1504 (United States)

    2012-09-11

    Classically supersymmetric Wilson loop on a null polygonal contour possesses all symmetries required to match it onto non-MHV amplitudes in maximally supersymmetric Yang-Mills theory. However, to define it quantum mechanically, one is forced to regularize it since perturbative loop diagrams are not well defined due to presence of ultraviolet divergences stemming from integration in the vicinity of the cusps. A regularization that is adopted by practitioners by allowing one to use spinor helicity formalism, on the one hand, and systematically go to higher orders of perturbation theory is based on a version of dimensional regularization, known as Four-Dimensional Helicity scheme. Recently it was demonstrated that its use for the super Wilson loop at one loop breaks both conformal symmetry and Poincare supersymmetry. Presently, we exhibit the origin for these effects and demonstrate how one can undo this breaking. The phenomenon is alike the one emerging in renormalization group mixing of conformal operators in conformal theories when one uses dimensional regularization. The rotation matrix to the diagonal basis is found by means of computing the anomaly in the Ward identity for the conformal boost. Presently, we apply this ideology to the super Wilson loop. We compute the one-loop conformal anomaly for the super Wilson loop and find that the anomaly depends on its Grassmann coordinates. By subtracting this anomalous contribution from the super Wilson loop we restore its interpretation as a dual description for reduced non-MHV amplitudes which are expressed in terms of superconformal invariants.

  20. Supersymmetry on curved spaces and superconformal anomalies

    CERN Document Server

    Cassani, Davide

    2013-01-01

    We study the consequences of unbroken rigid supersymmetry of four-dimensional field theories placed on curved manifolds. We show that in Lorentzian signature the background vector field coupling to the R-current is determined by the Weyl tensor of the background metric. In Euclidean signature, the same holds if two supercharges of opposite R-charge are preserved, otherwise the (anti-)self-dual part of the vector field-strength is fixed by the Weyl tensor. As a result of this relation, the trace and R-current anomalies of superconformal field theories simplify, with the trace anomaly becoming purely topological. In particular, in Lorentzian signature, or in the presence of two Euclidean supercharges of opposite R-charge, supersymmetry of the background implies that the term proportional to the central charge c vanishes, both in the trace and R-current anomalies. This is equivalent to the vanishing of a superspace Weyl invariant. We comment on the implications of our results for holography.

  1. Chiral anomaly and transport in Weyl metals

    Science.gov (United States)

    Burkov, A. A.

    2015-03-01

    We present an overview of our recent work on transport phenomena in Weyl metals, which may be connected to their nontrivial topological properties, particularly to chiral anomaly. We argue that there are two basic phenomena, which are related to chiral anomaly in Weyl metals: anomalous Hall effect (AHE) and chiral magnetic effect (CME). While AHE is in principle present in any ferromagnetic metal, we demonstrate that a magnetic Weyl metal is distinguished from an ordinary ferromagnetic metal by the absence of the extrinsic and the Fermi surface part of the intrinsic contributions to the AHE, as long as the Fermi energy is sufficiently close to the Weyl nodes. The AHE in a Weyl metal is thus shown to be a purely intrinsic, universal property, fully determined by the location of the Weyl nodes in the first Brillouin zone. In other words, a ferromagnetic Weyl metal may be thought of as the only example of a ferromagnetic metal with a purely intrinsic AHE. We further develop a fully microscopic theory of diffusive magnetotransport in Weyl metals. We derive coupled diffusion equations for the total and axial (i.e. node-antisymmetric) charge densities and show that chiral anomaly manifests as a magnetic-field-induced coupling between them. We demonstrate that an experimentally-observable consequence of CME in magnetotransport in Weyl metals is a quadratic negative magnetoresistance, which will dominate all other contributions to magnetoresistance under certain conditions and may be regarded as a smoking-gun transport characteristic, unique to Weyl metals.

  2. Calendar anomalies in the Ukrainian stock market

    Directory of Open Access Journals (Sweden)

    Guglielmo Maria Caporale

    2017-03-01

    Full Text Available This paper is a comprehensive investigation of calendar anomalies in the Ukrainian stock market. It employs various statistical techniques (average analysis, Student’s t-test, ANOVA, the Kruskal-Wallis test, and regression analysis with dummy variables and a trading simulation approach to test for the presence of the following anomalies: day-of-the-week effect; turn-of-the-month effect; turn-of-the-year effect; month-of-the-year effect; January effect; holiday effect; Halloween effect. The results suggest that in general calendar anomalies are not present in the Ukrainian stock market, but there are a few exceptions, i.e. the turn-of-the-year and Halloween effect for the PFTS index, and the month-of-the-year effect for UX futures. However, the trading simulation analysis shows that only trading strategies based on the turn-of-the-year effect for the PFTS index and the month-of-the-year effect for the UX futures can generate exploitable profit opportunities that can be interpreted as evidence against market efficiency.

  3. Identification of Geochemical Anomaly by Multifractal Analysis

    Institute of Scientific and Technical Information of China (English)

    Xie Shuyun; Cheng Qiuming; Ke Xianzhong; Bao Zhengyu; Wang Changming; Quan Haoli

    2008-01-01

    The separation of anomalies from geochemical background is an important part of data analysis because lack of such identifications might have profound influence on or even distort the final analysis results. In this article, 1 672 geochemical analytical data of 11 elements, including Cu, Mo, Ag, Sn, and others, from a region within Tibet, South China, are used as one example. Together with the traditional anomaly recognition method of using the iterative mean ±2σ, local multifractality theory has been utilized to delineate the ranges of geochemical anomalies of the elements. To different degrees, on the basis of original data mapping, C-A fractal analysis and singularity exponents, Sn differs from the other 10 elements. Moreover, geochemical mapping results based on values of the multifractal asymmetry index for all elements delineate the highly anomalous area. Similar to other 10 elements, the anomalous areas of Sn delineated by the asymmetry index distribute along the main structure orientations. According to the asymmetry indexes, the 11 elements could be classified into 3 groups: (1) Ag and Au, (2) As-Sb-Cu-Pb-Zn-Mo, and (3) Sn-Bi-W.This paragenetic association of elements can be used to interpret possible origins of mineralization, which is in agreement with petrological analysis and field survey results.

  4. A rapid and sensitive assay of intercellular coupling by voltage imaging of gap junction networks.

    Science.gov (United States)

    Ceriani, Federico; Mammano, Fabio

    2013-10-21

    A variety of mechanisms that govern connexin channel gating and permeability regulate coupling in gap junction networks. Mutations in connexin genes have been linked to several pathologies, including cardiovascular anomalies, peripheral neuropathy, skin disorders, cataracts and deafness. Gap junction coupling and its patho-physiological alterations are commonly assayed by microinjection experiments with fluorescent tracers, which typically require several minutes to allow dye transfer to a limited number of cells. Comparable or longer time intervals are required by fluorescence recovery after photobleaching experiments. Paired electrophysiological recordings have excellent time resolution but provide extremely limited spatial information regarding network connectivity. Here, we developed a rapid and sensitive method to assay gap junction communication using a combination of single cell electrophysiology, large-scale optical recordings and a digital phase-sensitive detector to extract signals with a known frequency from Vf2.1.Cl, a novel fluorescent sensor of plasma membrane potential. Tests performed in HeLa cell cultures confirmed that suitably encoded Vf2.1.Cl signals remained confined within the network of cells visibly interconnected by fluorescently tagged gap junction channels. We used this method to visualize instantly intercellular connectivity over the whole field of view (hundreds of cells) in cochlear organotypic cultures from postnatal mice. A simple resistive network model reproduced accurately the spatial dependence of the electrical signals throughout the cellular network. Our data suggest that each pair of cochlear non-sensory cells of the lesser epithelial ridge is coupled by ~1500 gap junction channels, on average. Junctional conductance was reduced by 14% in cochlear cultures harboring the T5M mutation of connexin30, which induces a moderate hearing loss in connexin30T5M/T5M knock-in mice, and by 91% in cultures from connexin30-/- mice, which are

  5. Transcriptional mechanisms coordinating tight junction assembly during epithelial differentiation.

    Science.gov (United States)

    Boivin, Felix J; Schmidt-Ott, Kai M

    2017-06-01

    Epithelial tissues form a selective barrier via direct cell-cell interactions to separate and establish concentration gradients between the different compartments of the body. Proper function and formation of this barrier rely on the establishment of distinct intercellular junction complexes. These complexes include tight junctions, adherens junctions, desmosomes, and gap junctions. The tight junction is by far the most diverse junctional complex in the epithelial barrier. Its composition varies greatly across different epithelial tissues to confer various barrier properties. Thus, epithelial cells rely on tightly regulated transcriptional mechanisms to ensure proper formation of the epithelial barrier and to achieve tight junction diversity. Here, we review different transcriptional mechanisms utilized during embryogenesis and disease development to promote tight junction assembly and maintenance of intercellular barrier integrity. We focus particularly on the Grainyhead-like transcription factors and ligand-activated nuclear hormone receptors, two central families of proteins in epithelialization. © 2017 New York Academy of Sciences.

  6. Remark on the Consistent Gauge Anomaly in Supersymmetric Theories

    CERN Document Server

    Ohshima, Y; Suzuki, H; Yasuta, H; Ohshima, Yoshihisa; Okuyama, Kiyoshi; Suzuki, Hiroshi; Yasuta, Hirofumi

    1999-01-01

    We present a direct field theoretical calculation of the consistent gauge anomaly in the superfield formalism, on the basis of a definition of the effective action through the covariant gauge current. The scheme is conceptually and technically simple and the gauge covariance in intermediate steps reduces calculational labors considerably. The resultant superfield anomaly, being proportional to the anomaly $d^{abc}=\\tr T^a\\{T^b,T^c\\}$, is minimal even without supplementing any counterterms. Our anomaly coincides with the anomaly obtained by Marinkovi\\'c as the solution of the Wess-Zumino consistency condition.

  7. [Congenital anomalies of the central nervous system in autopsy specimens].

    Science.gov (United States)

    Sobaniec-Lotowska, M; Ostapiuk, H; Sulkowski, S; Sobaniec, W; Sulik, M; Famulski, W

    1989-02-01

    On the basis of an analysis of 2398 autopsies of infants aged up to 1 year in 194 cases congenital anomalies of the central nervous system were found (8.1%). Most cases of these anomalies were noted in the group of newborns (85%) and the most frequent anomalies were: myelomeningocele (35.6%), multiple anomalies (20.1%), congenital hydrocephalus (17%), anencephaly (14.4%) and corpus callosum malformations (3.6%). Myelomeningocele, congenital hydrocephalus, anencephaly and true microcephaly were more frequent in girls, while multiple anomalies and corpus callosum malformations were more frequent in boys.

  8. Network Traffic Anomalies Identification Based on Classification Methods

    Directory of Open Access Journals (Sweden)

    Donatas Račys

    2015-07-01

    Full Text Available A problem of network traffic anomalies detection in the computer networks is analyzed. Overview of anomalies detection methods is given then advantages and disadvantages of the different methods are analyzed. Model for the traffic anomalies detection was developed based on IBM SPSS Modeler and is used to analyze SNMP data of the router. Investigation of the traffic anomalies was done using three classification methods and different sets of the learning data. Based on the results of investigation it was determined that C5.1 decision tree method has the largest accuracy and performance and can be successfully used for identification of the network traffic anomalies.

  9. The dynamic Allan Variance IV: characterization of atomic clock anomalies.

    Science.gov (United States)

    Galleani, Lorenzo; Tavella, Patrizia

    2015-05-01

    The number of applications where precise clocks play a key role is steadily increasing, satellite navigation being the main example. Precise clock anomalies are hence critical events, and their characterization is a fundamental problem. When an anomaly occurs, the clock stability changes with time, and this variation can be characterized with the dynamic Allan variance (DAVAR). We obtain the DAVAR for a series of common clock anomalies, namely, a sinusoidal term, a phase jump, a frequency jump, and a sudden change in the clock noise variance. These anomalies are particularly common in space clocks. Our analytic results clarify how the clock stability changes during these anomalies.

  10. Ballistic transport in InSb Josephson junctions

    Science.gov (United States)

    Damasco, John Jeffrey; Gill, Stephen; Car, Diana; Bakkers, Erik; Mason, Nadya

    We present transport measurements on Josephson junctions consisting of InSb nanowires contacted by Al at various junction lengths. Junction behavior as a function of gate voltage, electric field, and magnetic field is discussed. We show that short junctions behave as 1D quantum wires, exhibiting quantized conductance steps. In addition, we show how Josephson behavior changes as transport evolves from ballistic to diffusive as a function of contact spacing.

  11. Dynamics near Resonance Junctions in Hamiltonian Systems

    CERN Document Server

    Goto, S; Goto, Shin-itiro; Nozaki, Kazuhiro

    1999-01-01

    An approximate Poincare map near equally strong multiple resonances is reduced by means the method of averaging. Near the resonance junction of three degrees of freedom, we find that some homoclinic orbits ``whiskers'' in single resonance lines survive and form nearly periodic orbits, each of which looks like a pair of homoclinic orbits.

  12. Cooling of suspended nanostructures with tunnel junctions

    OpenAIRE

    Koppinen, P. J.; Maasilta, I. J.

    2009-01-01

    We have investigated electronic cooling of suspended nanowires with SINIS tunnel junction coolers. The suspended samples consist of a free standing nanowire suspended by four narrow ($\\sim$ 200 nm) bridges. We have compared two different cooler designs for cooling the suspended nanowire. We demonstrate that cooling of the nanowire is possible with a proper SINIS cooler design.

  13. Polyphosphonium-based ion bipolar junction transistors.

    Science.gov (United States)

    Gabrielsson, Erik O; Tybrandt, Klas; Berggren, Magnus

    2014-11-01

    Advancements in the field of electronics during the past few decades have inspired the use of transistors in a diversity of research fields, including biology and medicine. However, signals in living organisms are not only carried by electrons but also through fluxes of ions and biomolecules. Thus, in order to implement the transistor functionality to control biological signals, devices that can modulate currents of ions and biomolecules, i.e., ionic transistors and diodes, are needed. One successful approach for modulation of ionic currents is to use oppositely charged ion-selective membranes to form so called ion bipolar junction transistors (IBJTs). Unfortunately, overall IBJT device performance has been hindered due to the typical low mobility of ions, large geometries of the ion bipolar junction materials, and the possibility of electric field enhanced (EFE) water dissociation in the junction. Here, we introduce a novel polyphosphonium-based anion-selective material into npn-type IBJTs. The new material does not show EFE water dissociation and therefore allows for a reduction of junction length down to 2 μm, which significantly improves the switching performance of the ion transistor to 2 s. The presented improvement in speed as well the simplified design will be useful for future development of advanced iontronic circuits employing IBJTs, for example, addressable drug-delivery devices.

  14. Flux interactions on stacked Josephson junctions

    DEFF Research Database (Denmark)

    Scott, Alwyn C.; A., Petraglia

    1996-01-01

    Perturbation methods are used to study the dynamics of locked fluxon modes on stacked Josephson junctions and single crystals of certain high-T-c, superconductors. Two limiting cases are considered: (i) The nonlinear diffusion regime in which fluxon dynamics are dominated by energy exchange betwe...

  15. Defect formation in long Josephson junctions

    DEFF Research Database (Denmark)

    Gordeeva, Anna; Pankratov, Andrey

    2010-01-01

    We study numerically a mechanism of vortex formation in a long Josephson junction within the framework of the one-dimensional sine-Gordon model. This mechanism is switched on below the critical temperature. It is shown that the number of fluxons versus velocity of cooling roughly scales according...

  16. Gap junction diseases of the skin.

    NARCIS (Netherlands)

    Steensel, M.A.M. van

    2004-01-01

    Gap junctions are intercellular channels that allow the passage of water, ions, and small molecules. They are involved in quick, short-range messaging between cells and are found in skin, nervous tissue, heart, and muscle. An increasing number of hereditary skin disorders appear to be caused by muta

  17. Gap junctions-guards of excitability

    DEFF Research Database (Denmark)

    Stroemlund, Line Waring; Jensen, Christa Funch; Qvortrup, Klaus;

    2015-01-01

    Cardiomyocytes are connected by mechanical and electrical junctions located at the intercalated discs (IDs). Although these structures have long been known, it is becoming increasingly clear that their components interact. This review describes the involvement of the ID in electrical disturbances...

  18. Fluxon density waves in long Josephson junctions

    DEFF Research Database (Denmark)

    Olsen, O. H.; Ustinov, A. V.; Pedersen, Niels Falsig

    1993-01-01

    Numerical simulations of the multiple fluxon dynamics stimulated by an external oscillating force applied at a boundary of a long Josephson junction are presented. The calculated IV characteristics agree well with a recent experimental observation of rf-induced satellite flux-flow steps. The volt...... density waves....

  19. Transmembrane potentials of canine AV junctional tissues.

    Science.gov (United States)

    Tse, W W

    1986-06-01

    The atrioventricular (AV) junction comprises the AV node, His bundle (HB), and specialized tissues proximal to the node called paranodal fibers (PNF). In the present study, an in vitro, dissection-exposed canine right atrial (RA), transitional fiber (TF), AV junctional preparation was used. The TF and PNF formed a pathway running along the base of the septal cusp of the tricuspid valve (SCTV). In the first experiment, impulses elicited at the RA were monitored to propagate sequentially through the TF, PNF, AV node, and then the HB. This functional evidence supports the concept that a conduction pathway connecting the RA and the AV node exists along the base of the SCTV. This internodal pathway is referred to as the septal cusp pathway. In another experiment, transmembrane potentials and Vmax were determined on each of the AV junctional tissues. Results showed that PNF had the lowest Vmax (2.5 V/sec), followed by AV node (7.0 V/sec) and HB (33 V/sec). This finding showed that PNF, and not the AV node, has the lowest Vmax, suggesting that the PNF has the lowest conductivity among the AV junctional tissues, and this study advances our understanding on the mechanism of AV conduction delay in dog hearts.

  20. Lateral junction dynamics lead the way out.

    Science.gov (United States)

    Behrndt, Martin; Heisenberg, Carl-Philipp

    2014-02-01

    Epithelial cell layers need to be tightly regulated to maintain their integrity and correct function. Cell integration into epithelial sheets is now shown to depend on the N-WASP-regulated stabilization of cortical F-actin, which generates distinct patterns of apical-lateral contractility at E-cadherin-based cell-cell junctions.

  1. Soliton excitations in Josephson tunnel junctions

    DEFF Research Database (Denmark)

    Lomdahl, P. S.; Sørensen, O. H.; Christiansen, Peter Leth

    1982-01-01

    on the Nth ZFS yields the frequency Nf1 Coexistence of two adjacent frequencies is found on the third ZFS of the longer junction (L / λJ=6) in a narrow range of bias current as also found in the experiments. Small asymmetries in the experimental environment, a weak magnetic field, e.g., is introduced via...

  2. Gap junction diseases of the skin.

    NARCIS (Netherlands)

    Steensel, M.A.M. van

    2004-01-01

    Gap junctions are intercellular channels that allow the passage of water, ions, and small molecules. They are involved in quick, short-range messaging between cells and are found in skin, nervous tissue, heart, and muscle. An increasing number of hereditary skin disorders appear to be caused by muta

  3. Fluxon Dynamics in Elliptic Annular Josephson Junctions

    DEFF Research Database (Denmark)

    Monaco, Roberto; Mygind, Jesper

    2016-01-01

    We analyze the dynamics of a magnetic flux quantum (current vortex) trapped in a current-biased long planar elliptic annular Josephson tunnel junction. The system is modeled by a perturbed sine-Gordon equation that determines the spatial and temporal behavior of the phase difference across the tu...

  4. Intercellular junctions in nerve-free hydra

    DEFF Research Database (Denmark)

    McDowall, A W; Grimmelikhuijzen, C J

    1980-01-01

    with particles in an "enplaque conformation appearing as a raised plateau on the E-face or as a depression on the P-face; (ii) structures morphologically similar to gap junctions in rat liver, containing particles on the P-face and corresponding pits on the E-face, both having hexagonal packing with a lattice...

  5. All-carbon molecular tunnel junctions.

    Science.gov (United States)

    Yan, Haijun; Bergren, Adam Johan; McCreery, Richard L

    2011-11-30

    This Article explores the idea of using nonmetallic contacts for molecular electronics. Metal-free, all-carbon molecular electronic junctions were fabricated by orienting a layer of organic molecules between two carbon conductors with high yield (>90%) and good reproducibility (rsd of current density at 0.5 V carbon devices exhibit current density-voltage (J-V) behavior similar to those with metallic Cu top contacts. However, the all-carbon devices display enhanced stability to bias extremes and greatly improved thermal stability. Completed carbon/nitroazobenzene(NAB)/carbon junctions can sustain temperatures up to 300 °C in vacuum for 30 min and can be scanned at ±1 V for at least 1.2 × 10(9) cycles in air at 100 °C without a significant change in J-V characteristics. Furthermore, these all-carbon devices can withstand much higher voltages and current densities than can Cu-containing junctions, which fail upon oxidation and/or electromigration of the copper. The advantages of carbon contacts stem mainly from the strong covalent bonding in the disordered carbon materials, which resists electromigration or penetration into the molecular layer, and provides enhanced stability. These results highlight the significance of nonmetallic contacts for molecular electronics and the potential for integration of all-carbon molecular junctions with conventional microelectronics.

  6. Mesh Currents and Josephson Junction Arrays

    OpenAIRE

    1995-01-01

    A simple but accurate mesh current analysis is performed on a XY model and on a SIMF model to derive the equations for a Josephson junction array. The equations obtained here turn out to be different from other equations already existing in the literature. Moreover, it is shown that the two models come from an unique hidden structure

  7. The Wald entropy and 6d conformal anomaly

    Directory of Open Access Journals (Sweden)

    Amin Faraji Astaneh

    2015-10-01

    Full Text Available We analyze the Wald entropy for different forms of the conformal anomaly in six dimensions. In particular we focus on the anomaly which arises in a holographic calculation of Henningson and Skenderis. The various presentations of the anomaly differ by some total derivative terms. We calculate the corresponding Wald entropy for surfaces which do not have an Abelian O(2 symmetry in the transverse direction although the extrinsic curvature vanishes. We demonstrate that for this class of surfaces the Wald entropy is different for different forms of the conformal anomaly. The difference is due to the total derivative terms present in the anomaly. We analyze the conformal invariance of the Wald entropy for the holographic conformal anomaly and demonstrate that the violation of the invariance is due to the contributions of the total derivative terms in the anomaly. Finally, we make more precise the general form for the Hung–Myers–Smolkin discrepancy.

  8. Zero-voltage nondegenerate parametric mode in Josephson tunnel junctions

    DEFF Research Database (Denmark)

    Pedersen, Niels Falsig

    1976-01-01

    A new parametric mode in a Josephson tunnel junction biased in the zero-voltage mode is suggested. It is a nondegenerate parametric excitation where the junction plasma resonance represents the input circuit, and a junction geometrical resonance represents the idler circuit. This nondegenerate mo...... for such a coupling. Journal of Applied Physics is copyrighted by The American Institute of Physics....

  9. Systematic study of shallow junction formation on germanium substrates

    DEFF Research Database (Denmark)

    Hellings, Geert; Rosseel, Erik; Clarysse, Trudo

    2011-01-01

    Published results on Ge junctions are benchmarked systematically using RS–XJ plots. The electrical activation level required to meet the ITRS targets is calculated. Additionally, new results are presented on shallow furnace-annealed B junctions and shallow laser-annealed As junctions. Co-implanti...

  10. Long Josephson Junction Stack Coupled to a Cavity

    DEFF Research Database (Denmark)

    Madsen, Søren Peder; Pedersen, Niels Falsig; Groenbech-Jensen, N.

    2007-01-01

    A stack of inductively coupled long Josephson junctions are modeled as a system of coupled sine-Gordon equations. One boundary of the stack is coupled electrically to a resonant cavity. With one fluxon in each Josephson junction, the inter-junction fluxon forces are repulsive. We look at a possible...

  11. Structure Stability of Ⅰ-Type Carbon Nanotube Junctions

    Institute of Scientific and Technical Information of China (English)

    夏丹; 袁喆; 李家明

    2002-01-01

    Carbon nanotubes with junctions may play an important role in future ‘nanoelectronics' and future ‘nano devices'.In particular, junctions constructed with metal and semiconducting nanotubes have potential applications. Basedon the orthogonal tight-binding molecular dynamics method, we present our study of the structure stability ofI-type carbon nanotube junctions.

  12. Vacuum Tight Threaded Junctions (VTTJ): A new solution for reliable heterogeneous junctions in ITER

    Energy Technology Data Exchange (ETDEWEB)

    Agostinetti, P., E-mail: piero.agostinetti@igi.cnr.it; Palma, M. Dalla; Agostini, F. Degli; Marcuzzi, D.; Rizzolo, A.; Rossetto, F.; Sonato, P.; Zaccaria, P.

    2015-10-15

    Highlights: • Heterogeneous junctions represent a critical issue in Nuclear Fusion experiments. • We have developed a new technique for heterogeneous junctions, called VTTJ, whose main advantages are low cost, high reliability and easiness of construction. • The VTTJ junctions have passed all the tests required by ITER for the heterogeneous junctions of the divertor. • Further tests have demonstrated wide margins for operation (up to 700 °C and 500 bar). - Abstract: A new technique, called Vacuum Tight Threaded Junction (VTTJ), has been developed and patented by Consorzio RFX, permitting to obtain low-cost and reliable non-welded junctions, able to maintain vacuum tightness also in heavy loading conditions (high temperature and high mechanical loads). The technique can be applied also if the materials to be joint are not weldable and for heterogeneous junctions (for example, between steel and copper) and has been tested up to 500 bar internal pressure and up to 700 °C, showing excellent leak tightness in vacuum conditions and high mechanical resistance. The main advantages with respect to existing technologies (for example, friction welding and electron beam welding) are an easy construction, a low cost, a precise positioning of the junction and a high repeatability of the process. Due to these advantages, the new technique has been adopted for several components of the SPIDER experiment and it is proposed for ITER, in particular for the ITER Heat and Current Drive Neutral Beam Injector and for its prototype, the MITICA experiment, to be tested at Consorzio RFX. This paper gives a detailed description of the VTTJ technique, of the samples manufactured and of the qualification tests that have been carried out so far.

  13. The Dens: Normal Development, Developmental Variants and Anomalies, and Traumatic Injuries

    Directory of Open Access Journals (Sweden)

    William T O′Brien

    2015-01-01

    Full Text Available Accurate interpretation of cervical spine imagining can be challenging, especially in children and the elderly. The biomechanics of the developing pediatric spine and age-related degenerative changes predispose these patient populations to injuries centered at the craniocervical junction. In addition, congenital anomalies are common in this region, especially those associated with the axis/dens, due to its complexity in terms of development compared to other vertebral levels. The most common congenital variations of the dens include the os odontoideum and a persistent ossiculum terminale. At times, it is necessary to distinguish normal development, developmental variants, and developmental anomalies from traumatic injuries in the setting of acute traumatic injury. Key imaging features are useful to differentiate between traumatic fractures and normal or variant anatomy acutely; however, the radiologist must first have a basic understanding of the spectrum of normal developmental anatomy and its anatomic variations in order to make an accurate assessment. This review article attempts to provide the basic framework required for accurate interpretation of cervical spine imaging with a focus on the dens, specifically covering the normal development and ossification of the dens, common congenital variants and their various imaging appearances, fracture classifications, imaging appearances, and treatment options.

  14. Graphene junction field-effect transistor

    Science.gov (United States)

    Ou, Tzu-Min; Borsa, Tomoko; van Zeghbroeck, Bart

    2014-03-01

    We have demonstrated for the first time a novel graphene transistor gated by a graphene/semiconductor junction rather than an insulating gate. The transistor operates much like a semiconductor junction Field Effect Transistor (jFET) where the depletion layer charge in the semiconductor modulates the mobile charge in the channel. The channel in our case is the graphene rather than another semiconductor layer. An increased reverse bias of the graphene/n-silicon junction increases the positive charge in the depletion region and thereby reduces the total charge in the graphene. We fabricated individual graphene/silicon junctions as well as graphene jFETs (GjFETs) on n-type (4.5x1015 cm-3) silicon with Cr/Au electrodes and 3 μm gate length. As a control device, we also fabricated back-gated graphene MOSFETs using a 90nm SiO2 on a p-type silicon substrate (1019 cm-3) . The graphene was grown by APCVD on copper foil and transferred with PMMA onto the silicon substrate. The GjFET exhibited an on-off ratio of 3.75, an intrinsic graphene doping of 1.75x1012 cm-2, compared to 1.17x1013 cm-2 in the MOSFET, and reached the Dirac point at 13.5V. Characteristics of the junctions and transistors were measured as a function of temperature and in response to light. Experimental data and a comparison with simulations will be presented.

  15. Band Iron Formations and Satellite Magnetic Anomalies

    Science.gov (United States)

    Nazarova, K. A.; Wasilewski, P.

    2005-05-01

    Band Iron Formations (BIF) are mainly Precambrian (2.5-1.8 Ga) sedimentary deposits and are composed of alternating layers of iron rich material and silica (chert). Precambrian BIF mark growth in the level of free oxygen in the atmosphere and the ocean which happened about 2.2 Ga. Distribution of main BIF includes Hamersley Range, Australia; Transvaal-Griquatown, South Africa; Minas Gerais, Brazil; Labrador Trough, Canada, and Kursk-Krivoi Rog (Russia). Together these five very large BIF deposits constitute about 90 percent of Earth's total estimated BIF (5.76*10 14 ). On each continent these ancient rocks usually metamorphosed and crystallized include what are variously described as hematite-quartzites, banded iron formations, banded jaspers or calico-rocks. West African, Hudson Bay and Western Australian Satellite Magnetic Anomalies coincide with distribution BIF deposits. The Kursk Satellite Magnetic Anomaly (KMA) (about 22 nT at the altitude=400km, centered at 51o N, 37o E) also was identified by ground and aeromagnetic observations and is recognized as one of the largest magnetic anomaly on the Earth. Magnetic modeling shows that immense Precambrian iron ore deposits (iron bands) of Voronezh uplift are the main source of KMA. Magnetic properties of 10000 BIF samples outcropped in the KMA area have been measured and analyzed (Krutikhovskaya et al., 1964) Rockmag BIF dataset is presented at: http://core2.gsfc.nasa.gov/MPDB/datasets.html. Mean NRM value is about 42 A/M, Qn about 1.4. Demagnetization tests suggest that hard and stable NRM component is caused by hematite occurring in BIF in different forms and grain sizes. Hematite deposits discovered on Mars in western equatorial area with layered topography of Aram Chaos and Sinus Meridiani could be of hydrothermal origin and may be formed similar to hematite precipitated in BIF on Earth.

  16. Cerium anomaly at microscale in fossils.

    Science.gov (United States)

    Gueriau, Pierre; Mocuta, Cristian; Bertrand, Loïc

    2015-09-01

    Patterns in rare earth element (REE) concentrations are essential instruments to assess geochemical processes in Earth and environmental sciences. Excursions in the "cerium anomaly" are widely used to inform on past redox conditions in sediments. This proxy resources to the specificity of cerium to adopt both the +III and +IV oxidation states, while most rare earths are purely trivalent and share very similar reactivity and transport properties. In practical terms, the level of cerium anomaly is established through elemental point quantification and profiling. All these models rely on a supposed homogeneity of the cerium oxidation state within the samples. However, this has never been demonstrated, whereas the cerium concentration can significantly vary within a sample, as shown for fossils, which would vastly complicate interpretation of REE patterns. Here, we report direct micrometric mapping of Ce speciation through synchrotron X-ray absorption spectroscopy and production of local rare earth patterns in paleontological fossil tissues through X-ray fluorescence mapping. The sensitivity of the approach is demonstrated on well-preserved fishes and crustaceans from the Late Cretaceous (ca. 95 million years (Myr) old). The presence of Ce under the +IV form within the fossil tissues is attributed to slightly oxidative local conditions of burial and agrees well with the limited negative cerium anomaly observed in REE patterns. The [Ce(IV)]/[Ce(tot)] ratio appears remarkably stable at the microscale within each fossil and is similar between fossils from the locality. Speciation maps were obtained from an original combination of synchrotron microbeam X-ray fluorescence, absorption spectroscopy, and diffraction, together with light and electron microscopy. This work also highlights the need for more systematic studies of cerium geochemistry at the microscale in paleontological contexts, in particular across fossil histologies.

  17. The North German Conductivity Anomaly revisited

    Science.gov (United States)

    Schäfer, A.; Houpt, L.; Brasse, H.; Hoffmann, N.

    2011-10-01

    The North German Conductivity Anomaly was detected already in the early years of electromagnetic deep sounding. It refers to the reversal of induction arrows (as a graphical representation of the tipper transfer function, the ratio of vertical to horizontal magnetic field variations) at the northern and southern margins of the North German Basin. In spite of the many experiments carried out so far, its origin has remained ambiguous; explanations encompass a deep-crustal or even mantle source as well as the simple response to deepening of sedimentary sequences in the centre of the basin. Here, we report on modelling of new long-period magnetotelluric data collected along two profiles in NE Germany and S Sweden, with one transect crossing the Sorgenfrei-Tornquist Zone as the main boundary between Precambrian Baltica and the Palaeozoic belts of central Europe. With the exception of a few sites probably influenced by 3-D salt domes, the data allow a 2-D analysis. Resolution is reduced for large depths due to a well-conducting, saline aquifer, extending across the entire basin. The main result is that the reversal of induction arrows can largely be explained by the resistivity contrast between crystalline basement and sedimentary basin fill. Beneath Rügen island, a southward dipping conductor is interpreted to reflect an alum shale layer in Middle Cambrian-Lower Ordovician sediments. Beneath the southern basin, a moderately conductive upper mantle is modelled (although not very well resolved) which may reflect the thinning of the lithosphere as implied by seismic tomography. As the main anomalously inductive effect is primarily explained by the basin edges and numerous other anomalies exist inside the basin, we suggest not using the term 'North German Conductivity Anomaly' any longer.

  18. Comparison of Methods of Height Anomaly Computation

    Science.gov (United States)

    Mazurova, E.; Lapshin, A.; Menshova, A.

    2012-04-01

    As of today, accurate determination of height anomaly is one of the most difficult problems of geodesy, even with sustainable perfection of mathematical methods, computer possibilities. The most effective methods of height anomaly computation are based on the methods of discrete linear transformations, such as the Fast Fourier Transform (FFT), Short-Time Fourier Transform (STFT), Fast Wavelet Transform (FWT). The main drawback of the classical FFT is weak localization in the time domain. If it is necessary to define the time interval of a frequency presence the STFT is used that allows one to detect the presence of any frequency signal and the interval of its presence. It expands the possibilities of the method in comparison with the classical Fourier Transform. However, subject to Heisenberg's uncertainty principle, it is impossible to tell precisely what frequency signal is present at a given moment of time (it is possible to speak only about the range of frequencies); and it is impossible to tell at what precisely moment of time the frequency signal is present (it is possible to speak only about a time span). A wavelet-transform gives the chance to reduce the influence of the Heisenberg's uncertainty principle on the obtained time-and-frequency representation of the signal. With its help low frequencies have more detailed representation relative to the time, and high frequencies - relative to the frequency. The paper summarizes the results of height anomaly calculations done by the FFT, STFT, FWT methods and represents 3-D models of calculation results. Key words: Fast Fourier Transform(FFT), Short-Time Fourier Transform (STFT), Fast Wavelet Transform(FWT), Heisenberg's uncertainty principle.

  19. Structure and Transport Anomalies in Soft Colloids

    KAUST Repository

    Srivastava, Samanvaya

    2013-04-01

    Anomalous trends in nanoparticle correlation and motion are reported in soft nanoparticle suspensions using static and dynamic x-ray scattering measurements. Contrary to normal expectations, we find that particle-particle correlations decrease and particle dynamics become faster as volume fraction rises above a critical particle loading associated with overlap. Our observations bear many similarities to the cascade of structural and transport anomalies reported for complex, network forming molecular fluids such as water, and are argued to share similar physical origins. © 2013 American Physical Society.

  20. Imaging evaluation of fetal vascular anomalies

    Energy Technology Data Exchange (ETDEWEB)

    Calvo-Garcia, Maria A.; Kline-Fath, Beth M.; Koch, Bernadette L.; Laor, Tal [MLC 5031 Cincinnati Children' s Hospital Medical Center, Department of Radiology, Cincinnati, OH (United States); Adams, Denise M. [Cincinnati Children' s Hospital Medical Center, Department of Pediatrics and Hemangioma and Vascular Malformation Center, Cincinnati, OH (United States); Gupta, Anita [Cincinnati Children' s Hospital Medical Center, Department of Pathology, Cincinnati, OH (United States); Lim, Foong-Yen [Cincinnati Children' s Hospital Medical Center, Pediatric Surgery and Fetal Center of Cincinnati, Cincinnati, OH (United States)

    2015-08-15

    Vascular anomalies can be detected in utero and should be considered in the setting of solid, mixed or cystic lesions in the fetus. Evaluation of the gray-scale and color Doppler US and MRI characteristics can guide diagnosis. We present a case-based pictorial essay to illustrate the prenatal imaging characteristics in 11 pregnancies with vascular malformations (5 lymphatic malformations, 2 Klippel-Trenaunay syndrome, 1 venous-lymphatic malformation, 1 Parkes-Weber syndrome) and vascular tumors (1 congenital hemangioma, 1 kaposiform hemangioendothelioma). Concordance between prenatal and postnatal diagnoses is analyzed, with further discussion regarding potential pitfalls in identification. (orig.)

  1. Trusted Anomaly Detection with Context Dependency

    Institute of Scientific and Technical Information of China (English)

    PENG Xin-guang; YAN Mei-feng

    2006-01-01

    Anomaly detection of privileged processes is one of the most important means to safeguard the host and system security. The key problem for improving detection performance is to identify local behavior of the short sequences in traces of system calls accurately. An alternative modeling method was proposed based on the typical pattern matching of short sequences, which builds upon the concepts of short sequences with context dependency and the specially designed aggregation algorithm. The experimental results indicate that the modeling method considering the context dependency improves clearly the sensitive decision threshold as compared with the previous modeling method.

  2. Ectopia cordis: a rare congenital anomaly.

    Science.gov (United States)

    Gabriel, Abigail; Donnelly, Joseph; Kuc, Alexander; Good, Daniel; Doros, Gabriela; Matusz, Petru; Loukas, Marios

    2014-11-01

    Ectopia cordis (EC) is a rare congenital anomaly associated with the heart positioned outside of the thoracic cavity either partially or completely. The ectopic heart can be found along a spectrum of anatomical locations, including the cervical, thoracic and abdominal regions and in most cases, it protrudes outside the chest through a split sternum. Although the first case of EC was identified during the early 1600s only 91 cases have been reported since then in the literature. This review will discuss the history and prevalence of EC, its etiology, morphology, presentation and symptoms, complications, diagnosis, treatment and management and prognosis.

  3. A model for globular cluster extreme anomalies

    Science.gov (United States)

    D'Antona, F.; Ventura, P.

    2007-08-01

    In spite of the efforts made in recent years, there is still no comprehensive explanation for the chemical anomalies of globular cluster (GC) stars. Among these anomalies, the most striking is oxygen depletion, which reaches values down to [O/Fe] ~ -0.4 in most clusters, but in M13 it goes down to less than [O/Fe] ~ -1. In this work we suggest that the anomalies are due to the superposition of two different events, as follows. (i) Primordial self-enrichment; this is required to explain the oxygen depletion down to a minimum value [O/Fe] ~ -0.4. (ii) Extra mixing in a fraction of the stars already born with anomalous composition; these objects, starting with already low [O/Fe], will reduce the oxygen abundance down to the most extreme values. Contrary to other models that invoke extra mixing to explain the chemical anomalies, we suggest that this mixing is active only if there is a fraction of the stars in which the primordial composition is not only oxygen-depleted, but also extremely helium-rich (Y ~ 0.4), as found in a few GCs from their main-sequence multiplicity. We propose that the rotational evolution (and an associated extra mixing) of extremely helium-rich stars may be affected by the fact that they develop a very small or non-existent molecular weight barrier during the evolution. We show that extra mixing in these stars, having initial chemistry that has already been CNO processed, affects mainly the oxygen abundance, as well as (to a much smaller extent) the sodium abundance. The model also predicts a large fluorine depletion concomitant with the oxygen depletion, and a further enhancement of the surface helium abundance, which reaches values close to Y = 0.5 in the computed models. We stress that, in this tentative explanation, those stars that are primordially oxygen-depleted, but are not extremely helium-rich, do not suffer deep extra mixing.

  4. Conformal Anomaly and Large Scale Gravitational Coupling

    CERN Document Server

    Salehi, H

    2000-01-01

    We present a model in which the breackdown of conformal symmetry of a quantum stress-tensor due to the trace anomaly is related to a cosmological effect in a gravitational model. This is done by characterizing the traceless part of the quantum stress-tensor in terms of the stress-tensor of a conformal invariant classical scalar field. We introduce a conformal frame in which the anomalous trace is identified with a cosmological constant. In this conformal frame we establish the Einstein field equations by connecting the quantum stress-tensor with the large scale distribution of matter in the universe.

  5. Colours and anomalies of skin: diploma 2015

    OpenAIRE

    Marty, Nicolas; Geiser, Martial

    2016-01-01

    Afin de suivre et d’analyser l’évolution, lors de traitement ou pas, de lésions de la peau (grains de beauté, plaies, tâches de sénescence, coup de soleil …), nous avons développé une caméra portable munie d’une illumination multispectrale capable d’envoyer les images sur un serveur dédié et d’analyser ces images We developed a handheld camera with multispectral illumination to take pictures and to analyse anomalies of skin. The fields of use are: a) analysing and tracking skin lesions suc...

  6. Torque Anomaly in Quantum Field Theory

    CERN Document Server

    Fulling, S A; Trendafilova, C S

    2012-01-01

    The expectation values of energy density and pressure of a quantum field inside a wedge-shaped region appear to violate the expected relationship between torque and total energy as a function of angle. In particular, this is true of the well-known Deutsch--Candelas stress tensor for the electromagnetic field, whose definition requires no regularization except possibly at the vertex. Unlike a similar anomaly in the pressure exerted by a reflecting boundary against a perpendicular wall, this problem cannot be dismissed as an artifact of an ad hoc regularization.

  7. Second type of first branchial cleft anomaly

    Directory of Open Access Journals (Sweden)

    Hitesh Verma

    2016-01-01

    Full Text Available First branchial cleft fistula is a rare congenital malformation of the head and neck with an incidence of <8% of all branchial cleft defects. The patient presenting with discharging sinus in the neck with discharging ear should be investigated for a possible branchial cleft anomaly. Rarity and diverse presentation often lead to misdiagnosis and inadequate treatment. Recurrent infection and scarring make intraoperative identification of facial nerve made very difficult. We report a case of a 5-year-old boy with a first branchial cleft fistula, in which discharge was observed through the fistulous opening on the right side of the face and along the ear canal.

  8. Atom capture by nanotube and scaling anomaly

    CERN Document Server

    Giri, Pulak Ranjan

    2007-01-01

    The existence of bound state of the polarizable neutral atom in the inverse square potential created by the electric field of single walled charged carbon nanotube (SWNT) is shown to be theoretically possible. The consideration of inequivalent boundary conditions due to self-adjoint extensions lead to this nontrivial bound state solution. It is also shown that the scaling anomaly is responsible for the existence of bound state. Binding of the polarizable atoms in the coupling constant interval \\eta^2\\in[0,1) may be responsible for the smearing of the edge of steps in quantized conductance, which has not been considered so far in literature.

  9. Residual generator for cardiovascular anomalies detection

    KAUST Repository

    Belkhatir, Zehor

    2014-06-01

    This paper discusses the possibility of using observer-based approaches for cardiovascular anomalies detection and isolation. We consider a lumped parameter model of the cardiovascular system that can be written in a form of nonlinear state-space representation. We show that residuals that are sensitive to variations in some cardiovascular parameters and to abnormal opening and closure of the valves, can be generated. Since the whole state is not easily available for measurement, we propose to associate the residual generator to a robust extended kalman filter. Numerical results performed on synthetic data are provided.

  10. The chiral anomaly from M theory

    CERN Document Server

    Gursoy, U; Portugues, R; Gursoy, Umut; Hartnoll, Sean A.; Portugues, Ruben

    2003-01-01

    We argue that the chiral anomaly of $\\Ncal = 1$ super Yang-Mills theory admits a dual description as spontaneous symmetry breaking in M theory on $G_2$ holonomy manifolds. We identify an angle of the $G_2$ background dual to the anomalous $U(1)_R$ current in field theory. This angle is not an isometry of the metric and we therefore develop a theory of ``massive isometry'' to describe fluctuations about such angles. Another example of a massive isometry occurs in the Atiyah-Hitchin metric.

  11. Mouse models for understanding human developmental anomalies

    Energy Technology Data Exchange (ETDEWEB)

    Generoso, W.M.

    1989-01-01

    The mouse experimental system presents an opportunity for studying the nature of the underlying mutagenic damage and the molecular pathogenesis of this class of anomalies by virtue of the accessibility of the zygote and its descendant blastomeres. Such studies could contribute to the understanding of the etiology of certain sporadic but common human malformations. The vulnerability of the zygotes to mutagens as demonstrated in the studies described in this report should be a major consideration in chemical safety evaluation. It raises questions regarding the danger to human zygotes when the mother is exposed to drugs and environmental chemicals.

  12. Planar Josephson tunnel junctions in a transverse magnetic field

    DEFF Research Database (Denmark)

    Monacoa, R.; Aarøe, Morten; Mygind, Jesper

    2007-01-01

    Traditionally, since the discovery of the Josephson effect in 1962, the magnetic diffraction pattern of planar Josephson tunnel junctions has been recorded with the field applied in the plane of the junction. Here we discuss the static junction properties in a transverse magnetic field where...... demagnetization effects imposed by the tunnel barrier and electrodes geometry are important. Measurements of the junction critical current versus magnetic field in planar Nb-based high-quality junctions with different geometry, size, and critical current density show that it is advantageous to use a transverse...

  13. The computation of first order moments on junction trees

    CERN Document Server

    Djuric, Milos B; Stankovic, Miomir S

    2012-01-01

    We review some existing methods for the computation of first order moments on junction trees using Shafer-Shenoy algorithm. First, we consider the problem of first order moments computation as vertices problem in junction trees. In this way, the problem is solved using the memory space of an order of the junction tree edge-set cardinality. After that, we consider two algorithms, Lauritzen-Nilsson algorithm, and Mau\\'a et al. algorithm, which computes the first order moments as the normalization problem in junction tree, using the memory space of an order of the junction tree leaf-set cardinality.

  14. Associated anomalies in cases with anotia and microtia.

    Science.gov (United States)

    Stoll, Claude; Alembik, Yves; Dott, Beatrice; Roth, Marie-Paule

    2016-12-01

    Infants with anotia and microtia (AM) often have other non-AM associated congenital anomalies. The purpose of this investigation was to assess the prevalence and the types of these associated anomalies in a defined population. The associated anomalies in infants with AM were collected in all livebirths, stillbirths and terminations of pregnancy during 29 years in 387,067 consecutive births in the area covered by our population-based registry of congenital malformations. Of the 146 cases with AM registered during this period, representing a prevalence of 3.77 per 10,000, 49.3% had associated anomalies. There were 14 (9.6%) cases with chromosomal abnormalities including 5 trisomies 18, and 18 (12.3%) nonchromosomal recognized dysmorphic conditions including 6 cases with oculo-auriculo-vertebral spectrum. However, numerous other recognized dysmorphic conditions were registered. Forty (27.4%) of the cases had multiple congenital anomalies (MCA). Anomalies especially in the cardiovascular, the musculoskeletal, the urogenital, the central nervous, and the digestive systems, and facial clefts were the most common other anomalies. This study included special strengths: each affected child was examined by a geneticist, all elective terminations were ascertained, and the surveillance for anomalies was continued until 2 years of age. In conclusion the overall prevalence of associated anomalies, which was one in every two cases, emphasizes the need for a thorough investigation of cases with AM. A routine screening for other anomalies may be considered in infants and in fetuses with AM.

  15. On Bose–Einstein condensation in Josephson junctions star graph arrays

    Energy Technology Data Exchange (ETDEWEB)

    Lorenzo, M.; Lucci, M.; Merlo, V.; Ottaviani, I.; Salvato, M. [Dipartimento di Fisica and MINAS Lab, Università di Roma “Tor Vergata”, 00133 Roma (Italy); Cirillo, M., E-mail: cirillo@roma2.infn.it [Dipartimento di Fisica and MINAS Lab, Università di Roma “Tor Vergata”, 00133 Roma (Italy); Müller, F.; Weimann, T. [Physikalisch Technische Bundesanstalt, Bundesallee 100, D-38116 Braunschweig (Germany); Castellano, M.G.; Chiarello, F.; Torrioli, G. [IFN-CNR, Via Cineto Romano, I-00156 Roma (Italy)

    2014-01-31

    We report on the evidence of anomalous currents in graph-shaped arrays of Josephson junctions along peculiar branches of the networks. The specific case of a star-shaped array is considered and the evidence of the anomalies is achieved by comparing the current-voltage characteristics of the arrays embedded in the star structure with those of “reference” arrays which are fabricated by-side the network structure and are dc-isolated from these. The experimental data are consistent with the results of a theoretical model predicting gradients of the populations of Cooper pairs on the islands situated in proximity of the central superconductive island as a result of a Bose–Einstein condensation process.

  16. Physical model of back line-contact front-junction solar cells

    Science.gov (United States)

    Cuevas, Andres

    2013-04-01

    The analysis of advanced front-junction solar cells where the metal contact to the base region is locally formed on the back surface in the shape of lines usually requires numerical simulations. Here, we describe an approach based on a geometric formulation of carrier crowding towards the localized contact, in conjunction with a partition of the device in two distinct regions. This permits a one dimensional analysis of carrier flow, both in the region immediately adjacent to the contact and in the peripheral region surrounding it. The resulting model is simple enough to provide insight into the physics of device operation and reasonably accurate in cases of practical interest. By applying it to different cases, we identify unexpected anomalies and explain them in terms of the peculiar interplay between carrier transport and recombination that takes place in this type of solar cell.

  17. Anomalous Tunnel Magnetoresistance and Spin Transfer Torque in Magnetic Tunnel Junctions with Embedded Nanoparticles

    Science.gov (United States)

    Useinov, Arthur; Ye, Lin-Xiu; Useinov, Niazbeck; Wu, Te-Ho; Lai, Chih-Huang

    2015-12-01

    The tunnel magnetoresistance (TMR) in the magnetic tunnel junction (MTJ) with embedded nanoparticles (NPs) was calculated in range of the quantum-ballistic model. The simulation was performed for electron tunneling through the insulating layer with embedded magnetic and non-magnetic NPs within the approach of the double barrier subsystem connected in parallel to the single barrier one. This model can be applied for both MTJs with in-plane magnetization and perpendicular one. We also calculated the in-plane component of the spin transfer torque (STT) versus the applied voltage in MTJs with magnetic NPs and determined that its value can be much larger than in single barrier system (SBS) for the same tunneling thickness. The reported simulation reproduces experimental data of the TMR suppression and peak-like TMR anomalies at low voltages available in leterature.

  18. Broader than Broadway. Le anomalie dentro la griglia / Broader than Broadway. The anomalies within the grid

    Directory of Open Access Journals (Sweden)

    Job Floris

    2015-01-01

    Full Text Available La tipologia di edifici poco profondi e cuneiformi è emersa come conseguenza dell’incontro di un piano urbano inserito in un tessuto urbano esistente. Questo fenomeno compare in diverse città come New York o Parigi. Generalmente, queste anomalie non fanno parte della strategia urbana in modo conscio, ma sono eccezioni e difetti nella logica della pianificazione. Nonostante ciò sono la causa di momenti urbani affascinanti, nei quali l’unione tra urbanistica e architettura sembra dare del suo meglio. Queste anomalie si possono percepire sia come insoliti oggetti, sia come obbedienza al piano urbanistico. Seguendo le regole di quest'ultimo su tutta la linea, sorgono edifici grande importanza perche' pezzi indispensabili in grado di rafforzare la trama urbana. / The typology of thin, shallow and wedge-shaped buildings emerged as a consequence of the meeting of an implemented urban plan into an existing city-fabric. This phenomenon appears in several cities throughout the world such as New York or Paris. In general, these anomalies are not consciously part of the urban strategy, but exceptions and flaws in the logic of their urban plan. Nevertheless causing fascinating urban moments, where the merge of urbanism and architecture might be at its best. These anomalies can be perceived both as a strange object and the ultimate obedience to the urban plan. By following the rules of urbanism all the way, buildings with exotic proportions arise, of big importance since these indispensable pieces are enforcing the urban pattern.

  19. Abundance Anomalies In Tidal Disruption Events

    CERN Document Server

    Kochanek, C S

    2015-01-01

    The ~10% of tidal disruption events (TDEs) due to stars more massive than the Sun should show abundance anomalies due to stellar evolution in helium, carbon and nitrogen, but not oxygen. Helium is always enhanced, but only by up to ~25% on average because it becomes inaccessible once it is sequestered in the high density core as the star leaves the main sequence. However, portions of the debris associated with the disrupted core of a main sequence star can be enhanced in helium by factors of 2-3 for debris at a common orbital period. These helium abundance variations may be a contributor to the observed diversity of hydrogen and helium line strengths in TDEs. A still more striking anomaly is the rapid enhancement of nitrogen and the depletion of carbon due to the CNO cycle -- stars more massive than the Sun quickly show an increase in their average N/C ratio by factors of 3-10. Because low mass stars evolve slowly and high mass stars are rare, TDEs showing high N/C will almost all be due to 1-2Msun stars disr...

  20. Firewall policy anomaly detection and resolution

    Directory of Open Access Journals (Sweden)

    R.V. Darade

    2015-11-01

    Full Text Available Security of all private networks in businesses and institutions is achieved by firewall. Firewall provides protection by the quality of policy configured. Lack of Systematic analysis mechanism and Tools, Complex firewall configuration makes designing and managing firewall policies difficult. With help of segmentation rule, anomaly management framework is designed for accurate detection and effective resolution of anomalies. Using this technique, packets of network can be divided into set of disjoint packet space segments. Every segment is associated with unique set of firewall rules which specify an overlap relation among all firewall rules which could be conflicting or redundant. Flexible conflict resolution method is provided which has many resolution strategies for risk assessment of protected networks and its policy definition. Firewall logs are maintained by using association rule mining on these logs to find frequent logs, which in turned filtered to find malicious packets. Apriori algorithm is used to find frequent element from above logs. In each round, it computes the support for all candidate-item-sets. Candidate-item-sets with frequency above the minimum support parameter are selected at the end of each round; these frequent item-sets of round are used in the next round to construct candidate -item-sets. The algorithm halts when item-sets with desired frequency not found .

  1. Axial gravity, massless fermions and trace anomalies

    Science.gov (United States)

    Bonora, L.; Cvitan, M.; Prester, P. Dominis; Pereira, A. Duarte; Giaccari, S.; Štemberga, T.

    2017-08-01

    This article deals with two main topics. One is odd parity trace anomalies in Weyl fermion theories in a 4d curved background, the second is the introduction of axial gravity. The motivation for reconsidering the former is to clarify the theoretical background underlying the approach and complete the calculation of the anomaly. The reference is in particular to the difference between Weyl and massless Majorana fermions and to the possible contributions from tadpole and seagull terms in the Feynman diagram approach. A first, basic, result of this paper is that a more thorough treatment, taking account of such additional terms and using dimensional regularization, confirms the earlier result. The introduction of an axial symmetric tensor besides the usual gravitational metric is instrumental to a different derivation of the same result using Dirac fermions, which are coupled not only to the usual metric but also to the additional axial tensor. The action of Majorana and Weyl fermions can be obtained in two different limits of such a general configuration. The results obtained in this way confirm the previously obtained ones.

  2. Framework for behavioral analytics in anomaly identification

    Science.gov (United States)

    Touma, Maroun; Bertino, Elisa; Rivera, Brian; Verma, Dinesh; Calo, Seraphin

    2017-05-01

    Behavioral Analytics (BA) relies on digital breadcrumbs to build user profiles and create clusters of entities that exhibit a large degree of similarity. The prevailing assumption is that an entity will assimilate the group behavior of the cluster it belongs to. Our understanding of BA and its application in different domains continues to evolve and is a direct result of the growing interest in Machine Learning research. When trying to detect security threats, we use BA techniques to identify anomalies, defined in this paper as deviation from the group behavior. Early research papers in this field reveal a high number of false positives where a security alert is triggered based on deviation from the cluster learned behavior but still within the norm of what the system defines as an acceptable behavior. Further, domain specific security policies tend to be narrow and inadequately represent what an entity can do. Hence, they: a) limit the amount of useful data during the learning phase; and, b) lead to violation of policy during the execution phase. In this paper, we propose a framework for future research on the role of policies and behavior security in a coalition setting with emphasis on anomaly detection and individual's deviation from group activities.

  3. Detecting syntactic and semantic anomalies in schizophrenia.

    Science.gov (United States)

    Moro, Andrea; Bambini, Valentina; Bosia, Marta; Anselmetti, Simona; Riccaboni, Roberta; Cappa, Stefano F; Smeraldi, Enrico; Cavallaro, Roberto

    2015-12-01

    One of the major challenges in the study of language in schizophrenia is to identify specific levels of the linguistic structure that might be selectively impaired. While historically a main semantic deficit has been widely claimed, results are mixed, with also evidence of syntactic impairment. This might be due to heterogeneity in materials and paradigms across studies, which often do not allow to tap into single linguistic components. Moreover, the interaction between linguistic and neurocognitive deficits is still unclear. In this study, we concentrated on syntactic and semantic knowledge. We employed an anomaly detection task including short and long sentences with either syntactic errors violating the principles of Universal Grammar, or a novel form of semantic errors, resulting from a contradiction in the computation of the whole sentence meaning. Fifty-eight patients with diagnosis of schizophrenia were compared to 30 healthy subjects. Results showed that, in patients, only the ability to identify syntactic anomaly, both in short and long sentences, was impaired. This result cannot be explained by working memory abilities or psychopathological features. These findings suggest the presence of an impairment of syntactic knowledge in schizophrenia, at least partially independent of the cognitive and psychopathological profile. On the contrary, we cannot conclude that there is a semantic impairment, at least in terms of compositional semantics abilities.

  4. Effective Tolman temperature induced by trace anomaly

    Energy Technology Data Exchange (ETDEWEB)

    Eune, Myungseok [Sangmyung University, Department of Civil Engineering, Cheonan (Korea, Republic of); Gim, Yongwan [Sogang University, Department of Physics, Seoul (Korea, Republic of); Sogang University, Research Institute for Basic Science, Seoul (Korea, Republic of); Kim, Wontae [Sogang University, Department of Physics, Seoul (Korea, Republic of)

    2017-04-15

    Despite the finiteness of stress tensor for a scalar field on the four-dimensional Schwarzschild black hole in the Israel-Hartle-Hawking vacuum, the Tolman temperature in thermal equilibrium is certainly divergent on the horizon due to the infinite blue-shift of the Hawking temperature. The origin of this conflict is due to the fact that the conventional Tolman temperature was based on the assumption of a traceless stress tensor, which is, however, incompatible with the presence of the trace anomaly responsible for the Hawking radiation. Here, we present an effective Tolman temperature which is compatible with the presence of the trace anomaly by using the modified Stefan-Boltzmann law. Eventually, the effective Tolman temperature turns out to be finite everywhere outside the horizon, and so an infinite blue-shift of the Hawking temperature at the event horizon does not appear any more. In particular, it is vanishing on the horizon, so that the equivalence principle is exactly recovered at the horizon. (orig.)

  5. Firewall policy anomaly detection and resolution

    Directory of Open Access Journals (Sweden)

    Ms. R.V.Darade

    2014-06-01

    Full Text Available Security of all private networks in businesses and institutions is achieved by firewall. Firewall provides protection by the quality of policy configured. Lack of Systematic analysis mechanism and Tools, Complex firewall configuration makes designing and managing firewall policies difficult. With help of segmentation rule, anomaly management framework is designed for accurate detection and effective resolution of anomalies. Using this technique, packets of network can be divided into set of disjoint packet space segments. Every segment is associated with unique set of firewall rules which specify an overlap relation among all firewall rules whic h could be conflicting or redundant. Flexible conflict resolution method is provided which has many resolution stra tegies for risk assessment of protected networks and its policy definition. Firewall logs are maintained by using association rule mining on these logs to find frequent logs, which in turned filtered to find malicious packets. Apriori algorithm is used to find frequent element from above logs. In each round, it computes the support for all candidate-item-sets. Candidate-item-sets with frequency above the minimum support parameter are selected at the end of each round; these frequent item-sets of round are used in the next round to construct candidate -item-sets. The algorithm halts when item-sets with desired frequency not found .

  6. ENSO cycle and climate anomaly in China

    Institute of Scientific and Technical Information of China (English)

    CHEN Yongli; ZHAO Yongping; FENG Junqiao; WANG Fan

    2012-01-01

    The inter-annual variability of the tropical Pacific Subsurface Ocean Temperature Anomaly (SOTA) and the associated anomalous atmospheric circulation over the Asian North Pacific during the El Ni(n)o-Southern Oscillation (ENSO) were investigated using National Centers for Environmental Prediction/ National Center for Atmospheric Research (NCEP/NCAR) atmospheric reanalysis data and simple ocean data simulation (SODA).The relationship between the ENSO and the climate of China was revealed.The main results indicated the following:1) there are two ENSO modes acting on the subsurface tropical Pacific.The first mode is related to the mature phase of ENSO,which mainly appears during winter.The second mode is associated with a transition stage of the ENSO developing or decaying,which mainly occurs during summer; 2) during the mature phase of El Ni(n)o,the meridionality of the atmosphere in the mid-high latitude increases,the Aleutian low and high pressure ridge over Lake Baikal strengthens,northerly winds prevail in northern China,and precipitation in northern China decreases significantly.The ridge of the Ural High strengthens during the decaying phase of El Ni(n)o,as atmospheric circulation is sustained during winter,and the northerly wind anomaly appears in northern China during summer.Due to the ascending branch of the Walker circulation over the western Pacific,the western Pacific Subtropical High becomes weaker,and south-southeasterly winds prevail over southern China.As a result,less rainfall occurs over northern China and more rainfall over the Changjiang River basin and the southwestern and eastern region of Inner Mongolia.The flood disaster that occurred south of Changjiang River can be attributed to this.The La Ni(n)a event causes an opposite,but weaker effect; 3) the ENSO cycle can influence climate anomalies within China via zonal and meridional heat transport.This is known as the "atmospheric-bridge",where the energy anomaly within the tropical Pacific

  7. Craniocervical junction anomalies : morfological analysis by magnetic resonance imaging with considerations about joint function and brain stem physiology

    OpenAIRE

    Carolina de Medeiros Rimkus

    2008-01-01

    Resumo: A Junção craniocervical (JCC) é uma região anatômica de transição formada pelo osso occipital e pelas primeiras vértebras cervicais, o atlas e o axis. Esse arcabouço esquelético envolve importantes estruturas do sistema nervoso central (SNC), como o tronco cerebral, o cerebelo e a porção proximal da medula cervical. O complexo e delicado desenvolvimento embrionário dessa região sujeita essa topografia a diversas variações anatômicas e malformações congênitas. Embora algumas deformidad...

  8. String networks with junctions in competition models

    Science.gov (United States)

    Avelino, P. P.; Bazeia, D.; Losano, L.; Menezes, J.; de Oliveira, B. F.

    2017-03-01

    In this work we give specific examples of competition models, with six and eight species, whose three-dimensional dynamics naturally leads to the formation of string networks with junctions, associated with regions that have a high concentration of enemy species. We study the two- and three-dimensional evolution of such networks, both using stochastic network and mean field theory simulations. If the predation, reproduction and mobility probabilities do not vary in space and time, we find that the networks attain scaling regimes with a characteristic length roughly proportional to t 1 / 2, where t is the physical time, thus showing that the presence of junctions, on its own, does not have a significant impact on their scaling properties.

  9. Vibrational Heat Transport in Molecular Junctions

    Science.gov (United States)

    Segal, Dvira; Agarwalla, Bijay Kumar

    2016-05-01

    We review studies of vibrational energy transfer in a molecular junction geometry, consisting of a molecule bridging two heat reservoirs, solids or large chemical compounds. This setup is of interest for applications in molecular electronics, thermoelectrics, and nanophononics, and for addressing basic questions in the theory of classical and quantum transport. Calculations show that system size, disorder, structure, dimensionality, internal anharmonicities, contact interaction, and quantum coherent effects are factors that combine to determine the predominant mechanism (ballistic/diffusive), effectiveness (poor/good), and functionality (linear/nonlinear) of thermal conduction at the nanoscale. We review recent experiments and relevant calculations of quantum heat transfer in molecular junctions. We recount the Landauer approach, appropriate for the study of elastic (harmonic) phononic transport, and outline techniques that incorporate molecular anharmonicities. Theoretical methods are described along with examples illustrating the challenge of reaching control over vibrational heat conduction in molecules.

  10. String networks with junctions in competition models

    CERN Document Server

    Avelino, P P; Losano, L; Menezes, J; de Oliveira, B F

    2016-01-01

    In this work we give specific examples of competition models, with six and eight species, whose three-dimensional dynamics naturally leads to the formation of string networks with junctions, associated with regions that have a high concentration of enemy species. We study the two- and three-dimensional evolution of such networks, both using stochastic network and mean field theory simulations. If the predation, reproduction and mobility probabilities do not vary in space and time, we find that the networks attain scaling regimes with a characteristic length roughly proportional to $t^{1/2}$, where $t$ is the physical time, thus showing that the presence of junctions, on its own, does not have a significant impact on their scaling properties.

  11. Junction between surfaces of two topological insulators

    Science.gov (United States)

    Sen, Diptiman; Deb, Oindrila

    2012-02-01

    We study scattering from a line junction which separates the surfaces of two three-dimensional topological insulators; some aspects of this problem were recently studied in Takahashi and Murakami, Phys. Rev. Lett. 107, 166805 (2011). The velocities of the Dirac electrons on the two surfaces may be unequal and may even have opposite signs; in the latter case, we find that the electrons must, in general, go into the two-dimensional interface separating the two topological insulators. We also study what happens if the two surfaces are at an angle φ with respect to each other. We find in this case that there are bound states which propagate along the line junction with a velocity and direction of spin which depend on the bending angle φ.

  12. Current distributions in stripe Majorana junctions

    Science.gov (United States)

    Osca, Javier; Llorenç, Serra

    2017-02-01

    We calculate current and density distributions in stripe (2D planar) junctions between normal and Majorana nanowires having a finite ( y) transverse length. In presence of a magnetic field with vertical and in-plane components, the y-symmetry of the charge current distribution in the normal lead changes strongly across the Majorana phase transition: from center-symmetric if a Majorana mode is present to laterally-shifted (as expected by the Hall effect) if the field is tilted such as to destroy the Majorana mode due to the projection rule. We compare quasi-particle and charge distributions of current and density, as well as spin magnetizations. The Majorana mode causes opposite spin accumulations on the transverse sides of the junction and the emergence of a spin current.

  13. Boson Josephson Junction with Trapped Atoms

    Science.gov (United States)

    Raghavan, S.; Smerzi, A.; Fantoni, S.; Shenoy, S. R.

    We consider coherent atomic tunneling between two weakly coupled Bose-Einstein condensates at T=0 in a double-well trap. The condensate dynamics of the macroscopic amplitudes in the two wells is modeled by two Gross-Pitaevskii equations (GPE) coupled by a tunneling matrix element. Analytic elliptic function solutions are obtained for the time evolution of the inter-well fractional population imbalance z(t) (related to the condensate phase difference) of the Boson Josephson junction (BJJ). Surprisingly, the neutral-atom BJJ shows (non-sinusoidal generalizations of) effects seen in charged-electron superconductor Josephson junctions (SJJ). The BJJ elliptic-function behavior has a singular dependence on a GPE parameter ratio Λ at a critical ratio Λ=Λc, beyond which a novel 'macroscopic quantum self-trapping' effect sets in with a non-zero time-averaged imbalance ≠0.

  14. Non-Lagrangian theories from brane junctions

    Energy Technology Data Exchange (ETDEWEB)

    Bao, Ling [Chalmers Univ. of Technology, Goeteborg (Sweden); Mitev, Vladimir [Humboldt Univ., Berlin (Germany). Inst. fuer Mathematik und Inst. fuer Physik; Pomoni, Elli [Deutsches Elektronen-Synchrotron DESY, Hamburg (Germany). Theory Group; Taki, Masato [RIKEN Nishina Center, Saitama (Japan). Mathematical Physics Lab.; Yagi, Futoshi [International School of Advanced Studies (SISSA), Trieste (Italy); INFN, Trieste (Italy); Korea Institute for Advanced Study (KIAS), Seoul (Korea, Republic of)

    2013-10-15

    In this article we use 5-brane junctions to study the 5D T{sub N} SCFTs corresponding to the 5D N=1 uplift of the 4D N=2 strongly coupled gauge theories, which are obtained by compactifying N M5 branes on a sphere with three full punctures. Even though these theories have no Lagrangian description, by using the 5-brane junctions proposed by Benini, Benvenuti and Tachikawa, we are able to derive their Seiberg-Witten curves and Nekrasov partition functions. We cross-check our results with the 5D superconformal index proposed by Kim, Kim and Lee. Through the AGTW correspondence, we discuss the relations between 5D superconformal indices and n-point functions of the q-deformed W{sub N} Toda theories.

  15. An Important Member of Tight Junctions: Claudins

    Directory of Open Access Journals (Sweden)

    Ozlem Demirpence

    2016-01-01

    Full Text Available The tight junction (TJs, the most apically located of the intercellular junctional complexes, inhibits solute and water flow through the paracellular space, termed the %u201Cbarrier%u201D function. TJs participate in signal transduction mechanisms that regulate epithelial cell proliferation, gene expression, differentiation and morphogenesis. The claudin family of transmembrane proteins localized to the TJ. Loss of expression of Claudin causes of suppression TJs function. Recent studies have shown that altered levels of the different claudins may be related to invasion and progression of carcinoma cells in several primary neoplasms. A better knowledge of the mechanisms underlying carcinogenesis will likely result in the development of novel approaches for the diagnosis and therapy.

  16. Electron transport in doped fullerene molecular junctions

    Science.gov (United States)

    Kaur, Milanpreet; Sawhney, Ravinder Singh; Engles, Derick

    The effect of doping on the electron transport of molecular junctions is analyzed in this paper. The doped fullerene molecules are stringed to two semi-infinite gold electrodes and analyzed at equilibrium and nonequilibrium conditions of these device configurations. The contemplation is done using nonequilibrium Green’s function (NEGF)-density functional theory (DFT) to evaluate its density of states (DOS), transmission coefficient, molecular orbitals, electron density, charge transfer, current, and conductance. We conclude from the elucidated results that Au-C16Li4-Au and Au-C16Ne4-Au devices behave as an ordinary p-n junction diode and a Zener diode, respectively. Moreover, these doped fullerene molecules do not lose their metallic nature when sandwiched between the pair of gold electrodes.

  17. Charge Transport Phenomena in Peptide Molecular Junctions

    Directory of Open Access Journals (Sweden)

    Alessandra Luchini

    2008-01-01

    Full Text Available Inelastic electron tunneling spectroscopy (IETS is a valuable in situ spectroscopic analysis technique that provides a direct portrait of the electron transport properties of a molecular species. In the past, IETS has been applied to small molecules. Using self-assembled nanoelectronic junctions, IETS was performed for the first time on a large polypeptide protein peptide in the phosphorylated and native form, yielding interpretable spectra. A reproducible 10-fold shift of the I/V characteristics of the peptide was observed upon phosphorylation. Phosphorylation can be utilized as a site-specific modification to alter peptide structure and thereby influence electron transport in peptide molecular junctions. It is envisioned that kinases and phosphatases may be used to create tunable systems for molecular electronics applications, such as biosensors and memory devices.

  18. Major congenital anomalies in babies born with Down syndrome

    DEFF Research Database (Denmark)

    Morris, Joan K; Garne, Ester; Wellesley, Diana

    2014-01-01

    Previous studies have shown that over 40% of babies with Down syndrome have a major cardiac anomaly and are more likely to have other major congenital anomalies. Since 2000, many countries in Europe have introduced national antenatal screening programs for Down syndrome. This study aimed...... to determine if the introduction of these screening programs and the subsequent termination of prenatally detected pregnancies were associated with any decline in the prevalence of additional anomalies in babies born with Down syndrome. The study sample consisted of 7,044 live births and fetal deaths with Down...... syndrome registered in 28 European population-based congenital anomaly registries covering seven million births during 2000-2010. Overall, 43.6% (95% CI: 42.4-44.7%) of births with Down syndrome had a cardiac anomaly and 15.0% (14.2-15.8%) had a non-cardiac anomaly. Female babies with Down syndrome were...

  19. Prevalence and Distribution of Developmental Dental Anomalies in Pediatric Patients

    Directory of Open Access Journals (Sweden)

    Merve Erkmen Almaz

    2017-08-01

    Full Text Available Objective: The objective of this study was to evaluate the prevalence of dental anomalies in paediatric patients attending the Department of Paediatric Dentistry, Kırıkkale University Faculty of Dentistry. Materials and Methods: The study consisted a sample of 9173 patients, aged between 0-15 years, referred to our clinic between 1 August 2011-1 August 2012. The patients were examined clinically and radiographically in terms of the number, size, shape, structure and color anomalies. Results: One hundred sixty six children (1.8% were found to have developmental dental anomalies. The most frequently observed anomalies were congenitally missing teeth (0.52% and supernumerary teeth (0.27%. Anomalies such as dens invaginatus (0.03%, dentinogenesis imperfecta (0.02% and dilaceration (0.02% were encountered more rarely. Conclusion: Early diagnosis and determination of the prevalence of dental anomalies in children is important in the treatment planning.

  20. Geoid anomalies over Gorringe Ridge, North Atlantic Ocean

    Science.gov (United States)

    Souriau, A.

    1984-04-01

    The geoid anomalies over Gorringe Ridge, a very prominent high in the topography north of the Azores-Gibraltar plate boundary, have been deduced from Seasat alimetric data, and an interpretation of these anomalies together with the gravity anomalies is attempted. The geoid anomalies generated by the topographic high alone with the serpentinite density nearly fit the observed geoid anomalies, so that the structure must be either out of isostatic equilibrium or compensated at great depth. It is shown that a model in isostatic equilibrium with a small negative density contrast extending to 60 km depth or more explains both the gravity and geoid anomalies and is compatible with the deep seismicity north of Gorringe Ridge. Previous nonisostatic models, one involving an uplift of the upper mantle beneath the ridge, one describing a nascent subduction zone, and another involving flexure of the elastic part of the lithosphere due to the ridge loading, are discussed.

  1. Peltier Junction heats and cools car seat

    Energy Technology Data Exchange (ETDEWEB)

    Gottschalk, M.A.

    1994-10-10

    Electrically heated seats may soon become heated and cooled seats. The design called the CCS module exploits the heat-pump capability of a class of semiconductor thermoelectric devices (TEDs) known as Peltier Junction. Every CCS module contain two TEDs. Heating and cooling occurs through convection and conduction. The heart of the system is the thermoelectric heat pump. This is originally conceived as the sole heating/cooling options for a prototype electric vehicle.

  2. Josephson junction microwave modulators for qubit control

    Science.gov (United States)

    Naaman, O.; Strong, J. A.; Ferguson, D. G.; Egan, J.; Bailey, N.; Hinkey, R. T.

    2017-02-01

    We demonstrate Josephson junction based double-balanced mixer and phase shifter circuits operating at 6-10 GHz and integrate these components to implement both a monolithic amplitude/phase vector modulator and an I/Q quadrature mixer. The devices are actuated by flux signals, dissipate no power on chip, exhibit input saturation powers in excess of 1 nW, and provide cryogenic microwave modulation solutions for integrated control of superconducting qubits.

  3. Internal dynamics of long Josephson junction oscillators

    DEFF Research Database (Denmark)

    Christiansen, Peter Leth; Lomdahl, P. S.; Scott, Alwyn C.;

    1981-01-01

    Numerical computations on a sine-Gordon model of the Josephson junction fluxon oscillator are compared with experimental measurements. Good agreement is found for the voltage current characteristic, oscillator power output, and range of current bias over which oscillation is observed. Our numeric...... results imply a ''bunched-fluxon'' mode of oscillation at larger values of bias current. Applied Physics Letters is copyrighted by The American Institute of Physics....

  4. Decreased Vision and Junctional Scotoma from Pituicytoma

    Directory of Open Access Journals (Sweden)

    Nancy Huynh

    2012-05-01

    Full Text Available Pituicytomas are rare neoplasms of the sellar region. We report a case of vision loss and a junctional scotoma in a 43-year-old woman caused by compression of the optic chiasm by a pituitary tumor. The morphological and immunohistochemical characteristics of the tumor were consistent with the diagnosis of pituicytoma. The tumor was debulked surgically, and the patient’s vision improved.

  5. Brownian refrigeration by hybrid tunnel junctions

    OpenAIRE

    Peltonen, J. T.; Helle, M.; Timofeev, A. V.; Solinas, P.; Hekking, F. W. J.; Pekola, Jukka P.

    2011-01-01

    Voltage fluctuations generated in a hot resistor can cause extraction of heat from a colder normal metal electrode of a hybrid tunnel junction between a normal metal and a superconductor. We extend the analysis presented in Phys. Rev. Lett. 98, 210604 (2007) of this heat rectifying system, bearing resemblance to a Maxwell’s demon. Explicit analytic calculations show that the entropy of the total system is always increasing. We then consider a single-electron transistor configuration with two ...

  6. Interfacial capacitance effects in magnetic tunneling junctions

    CERN Document Server

    Landry, G; Du, J; Xiao, J Q

    2001-01-01

    We have investigated the AC transport properties of magnetic tunnel junctions (MTJ) in order to characterize interfacial properties. One such property is interfacial charge accumulation, which leads to a voltage drop in the electrodes of the MTJ and the measured capacitance differing from the geometrical capacitance. Through measurement of capacitance spectra, we have extracted an interfacial capacitance of 16 mu F/cm sup 2 per interface and a screening length of 0.55 A for FeNi electrodes.

  7. Gap junction channels and cardiac impulse propagation.

    Science.gov (United States)

    Desplantez, Thomas; Dupont, Emmanuel; Severs, Nicholas J; Weingart, Robert

    2007-08-01

    The role of gap junction channels on cardiac impulse propagation is complex. This review focuses on the differential expression of connexins in the heart and the biophysical properties of gap junction channels under normal and disease conditions. Structural determinants of impulse propagation have been gained from biochemical and immunocytochemical studies performed on tissue extracts and intact cardiac tissue. These have defined the distinctive connexin coexpression patterns and relative levels in different cardiac tissues. Functional determinants of impulse propagation have emerged from electrophysiological experiments carried out on cell pairs. The static properties (channel number and conductance) limit the current flow between adjacent cardiomyocytes and thus set the basic conduction velocity. The dynamic properties (voltage-sensitive gating and kinetics of channels) are responsible for a modulation of the conduction velocity during propagated action potentials. The effect is moderate and depends on the type of Cx and channel. For homomeric-homotypic channels, the influence is small to medium; for homomeric-heterotypic channels, it is medium to strong. Since no data are currently available on heteromeric channels, their influence on impulse propagation is speculative. The modulation by gap junction channels is most prominent in tissues at the boundaries between cardiac tissues such as sinoatrial node-atrial muscle, atrioventricular node-His bundle, His bundle-bundle branch and Purkinje fibers-ventricular muscle. The data predict facilitation of orthodromic propagation.

  8. Gap Junctions: The Claymore for Cancerous Cells

    Directory of Open Access Journals (Sweden)

    Ailar Nakhlband

    2011-07-01

    Full Text Available Introduction: Gap junctions play an important role in the cell proliferation in mammalian cells as well as carcinogenesis. However, there are controversial issues about their role in cancer pathogenesis. This study was designed to evaluate genotoxicity and cytotoxicity of Carbenoxolone (CBX as a prototype of inter-cellular gap junction blocker in MCF7 and BT20 human breast cancer cells. Methods: The MCF7and BT20 human breast cancer cell lines were cultivated, and treated at designated confluency with different doses of CBX. Cellular cytotoxicity was examined using standard colorimetric assay associated with cell viability tests. Gene expression evaluation was carried out using real time polymerase chain reaction (PCR. Results: MCF7 and BT20 cells were significantly affected by CBX in a dose dependent manner in cell viability assays. Despite varying expression of genes, down regulation of pro- and anti-apoptotic genes was observed in these cells. Conclusion: Based upon this investigation, it can be concluded that CBX could affect both low and high proliferative types of breast cancer cell lines and disproportionate down regulation of both pre- and anti-apoptotic genes may be related to interacting biomolecules, perhaps via gap junctions.

  9. Axial Anomaly in Lattice Abelian Gauge Theory in Arbitrary Dimensions

    CERN Document Server

    Fujiwara, T; Wu, K; Fujiwara, Takanori; Suzuki, Hiroshi; Wu, Ke

    1999-01-01

    Axial anomaly of lattice abelian gauge theory in hyper-cubic regular lattice in arbitrary even dimensions is investigated by applying the method of exterior differential calculus. The topological invariance, gauge invariance and locality of the axial anomaly determine the explicit form of the topological part. The anomaly is obtained up to a multiplicative constant for finite lattice spacing and can be interpreted as the Chern character of the abelian lattice gauge theory.

  10. Application of Noncommutative Differential Geometry on Lattice to Anomaly

    CERN Document Server

    Fujiwara, T; Wu, K; Fujiwara, Takanori; Suzuki, Hiroshi; Wu, Ke

    1999-01-01

    The chiral anomaly in lattice abelian gauge theory is investigated by applying the geometric and topological method in noncommutative differential geometry(NCDG). A new kind of double complex and descent equation are proposed on infinite hypercubic lattice in arbitrary even dimensional Euclidean space, in the framework of NCDG. Using the general solutions to proposed descent equation, we derive the chiral anomaly in Abelian lattice gauge theory. The topological origin of anomaly is nothing but the Chern classes in NCDG.

  11. Examining the relationship between skull size and dental anomalies

    OpenAIRE

    Krecioch, Joseph

    2014-01-01

    This study, reporting the results of a 2012 Master’s dissertation, of 131 skulls from 6 Classical to Medieval populations in Macedonia and England examined the relationship between craniometric variables and dental anomalies of shape, number, and position. Standard craniometric landmarks were measured and dental anomalies of shape, number, and position were recorded and tested for associations using SPSS. Rotations were the most common anomaly and were associated significantly with reduced ...

  12. Method for detecting software anomalies based on recurrence plot analysis

    OpenAIRE

    Michał Mosdorf

    2012-01-01

    Presented paper evaluates method for detecting software anomalies based on recurrence plot analysis of trace log generated by software execution. Described method for detecting software anomalies is based on windowed recurrence quantification analysis for selected measures (e.g. Recurrence rate - RR or Determinism - DET). Initial results show that proposed method is useful in detecting silent software anomalies that do not result in typical crashes (e.g. exceptions).

  13. Method for detecting software anomalies based on recurrence plot analysis

    Directory of Open Access Journals (Sweden)

    Michał Mosdorf

    2012-03-01

    Full Text Available Presented paper evaluates method for detecting software anomalies based on recurrence plot analysis of trace log generated by software execution. Described method for detecting software anomalies is based on windowed recurrence quantification analysis for selected measures (e.g. Recurrence rate - RR or Determinism - DET. Initial results show that proposed method is useful in detecting silent software anomalies that do not result in typical crashes (e.g. exceptions.

  14. On Certain Conceptual Anomalies in Einstein's Theory of Relativity

    OpenAIRE

    2008-01-01

    There are a number of conceptual anomalies occurring in the Standard exposition of Einstein’s Theory of Relativity. These anomalies relate to issues in both mathematics and in physics and penetrate to the very heart of Einstein’s theory. This paper reveals and amplifies a few such anomalies, including the fact that Einstein’s field equations for the so-called static vacuum configuration, R = 0 , violates his Principle of Equiv- alence, and is therefore ...

  15. Associated noncardiac congenital anomalies among cases with congenital heart defects.

    Science.gov (United States)

    Stoll, Claude; Dott, Beatrice; Alembik, Yves; Roth, Marie-Paule

    2015-02-01

    Cases with congenital heart defects (CHD) often have other associated anomalies. The purpose of this investigation was to assess the prevalence and the types of associated anomalies in CHD in a defined population. The anomalies associated with CHD were collected in all live births, stillbirths and terminations of pregnancy during 26 years in 346,831 consecutive pregnancies of known outcome in the area covered by our population based registry of congenital anomalies. Of the 4005 cases with CHD born during this period (total prevalence of 115.5 per 10,000), 1055 (26.3%) had associated major anomalies. There were 354 (8.8%) cases with chromosomal abnormalities including 218 trisomies 21, and 99 (2.5%) nonchromosomal recognized dysmorphic conditions. There were no predominant recognized dysmorphic conditions, but VACTERL association. However, other recognized dysmorphic conditions were registered including Noonan syndrome, fetal alcohol syndrome, and skeletal dysplasias. Six hundred and two (15.0%) of the cases had non syndromic, non chromosomal multiple congenital anomalies (MCA). Anomalies in the urinary tract, the musculoskeletal, the digestive, and the central nervous systems were the most common other anomalies. Prenatal diagnosis was obtained in 18.7% of the pregnancies. In conclusion the overall prevalence of associated anomalies, which was one in four infants, emphasizes the need for a thorough investigation of cases with CHD. A routine screening for other anomalies may be considered in infants and in fetuses with CHD. One should be aware that the anomalies associated with CHD can be classified into a recognizable anomaly, syndrome or pattern in one out of nine cases with CHD.

  16. Comparison of machine learning models for classification of BGP anomalies

    OpenAIRE

    2012-01-01

    Worms such as Slammer, Nimda, and Code Red~I are anomalies that affect performance of the global Internet Border Gateway Protocol (BGP). BGP anomalies also include Internet Protocol (IP) prefix hijacks, miss-configurations, and electrical failures. In this Thesis, we analyzed the feature selection process to choose the most correlated features for an anomaly class. We compare the Fisher, minimum redundancy maximum relevance (mRMR), odds ratio (OR), extended/multi-class/weighted odds ratio (EO...

  17. Molecular beam epitaxy growth of germanium junctions for multi-junction solar cell applications

    Science.gov (United States)

    Masuda, T.; Faucher, J.; Lee, M. L.

    2016-11-01

    We report on the molecular beam epitaxy (MBE) growth and device characteristics of Ge solar cells. Integrating a Ge bottom cell beneath a lattice-matched triple junction stack grown by MBE could enable ultra-high efficiencies without metamorphic growth or wafer bonding. However, a diffused junction cannot be readily formed in Ge by MBE due to the low sticking coefficient of group-V molecules on Ge surfaces. We therefore realized Ge junctions by growth of homo-epitaxial n-Ge on p-Ge wafers within a standard III-V MBE system. We then fabricated Ge solar cells, finding growth temperature and post-growth annealing to be key factors for achieving high efficiency. Open-circuit voltage and fill factor values of ~0.175 V and ~0.59 without a window layer were obtained, both of which are comparable to diffused Ge junctions formed by metal-organic vapor phase epitaxy. We also demonstrate growth of high-quality, single-domain GaAs on the Ge junction, as needed for subsequent growth of III-V subcells, and that the surface passivation afforded by the GaAs layer slightly improves the Ge cell performance.

  18. On the trace anomaly of a Weyl fermion

    CERN Document Server

    Bastianelli, Fiorenzo

    2016-01-01

    We calculate the trace anomaly of a Weyl fermion coupled to gravity by using Fujikawa's method supplemented by a consistent regulator. The latter is constructed out of Pauli-Villars regulating fields. The motivation for presenting such a calculation stems from recent studies that suggest that the trace anomaly of chiral fermions in four dimensions might contain an imaginary part proportional to the Pontryagin density. We find that the trace anomaly of a Weyl fermion is given by half the trace anomaly of a Dirac fermion, so that no imaginary part proportional to the Pontryagin density is seen to arise.

  19. FOETAL ULTRASOUND - NEUROECTODERMAL ANOMALIES IN RURAL PREGNANT WOMEN

    Directory of Open Access Journals (Sweden)

    Mala Venkata

    2016-06-01

    Full Text Available BACKGROUND A prospective clinical study to know the various types of congenital Neuroectodermal Anomalies on obstetric Ultrasound, in rural pregnant women. To reduce the maternal morbidity and mortality by early detection of these Congenital Neuroectodermal Anomalies. To calculate the incidence and prevalence of different types of Congenital Neuroectodermal Anomalies, in these rural pregnant women. To assist the obstetrician in taking decisions regarding the termination or continuation of the pregnancy in relation to the type of malformation and its prognosis. METHODS A prospective clinical study of Congenital Neuroectodermal Anomalies in 22,000 rural pregnant women coming to the Santhiram Medical College, Radiology Department for a routine obstetric scan. 44 cases of neuroectodermal anomalies were detected out of the 22000 cases, within an incidence of 2 per 1000 cases. Approximately 1 in every 500 cases showed an anomaly. RESULTS The most common lesions detected were hydrocephalus, and spina bifida followed by anencephaly. Association of these lesions with consanguinity, previous history of similar anomaly and intake of iron and folic acid tablets was noted. CONCLUSION Ultrasound is an excellent modality for the diagnosis and characterisation of the neuroectodermal anomalies. Its multiplanar imaging property along with real time image visualisation make it an excellent tool for the diagnosis and characterisation of these anomalies

  20. The Weyl anomaly and the nature of the background geometry

    CERN Document Server

    Quirós, I

    2000-01-01

    The Weyl anomaly problem is treated within a purely geometrical context. Arguments are given that hint at a possible classical origin of the conformal anomaly in the Riemannian nature of the background geometry where the matter fields play out their dynamics. Some considerations allowing for a possible resolution of the Weyl anomaly problem are briefly outlined. Following the spirit of the standard model of the fundamental interactions, it is argued that the Weyl anomaly should be a consequence of the breaking of the gauge symmetry at some stage during the evolution of the universe.