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Sample records for willi detector compared

  1. The modification and the installation of WILLI detector as a rotatable device

    International Nuclear Information System (INIS)

    Brancus, I. M.; Vulpescu, B.; Badea, A. F.; Bozdog, H.; Duma, M.; Petcu, M.; Aiftimiei, C.; Mitrica, B.; Wentz, J.; Rebel, H.; Bercuci, A.; Mathes, H. J.

    2001-01-01

    The compact WILLI device, built in IFIN-HH Bucharest (44026'N latitude and 26004'E longitude) at a vertical cut-off rigidity of 5.6 GV, has been used for measurements of the charge ratio in the vertical atmospheric muon flux at momenta bellow 1GeV/c. In this low energy range the studies of muon charge ratio provide information useful for the discussion of the so-called atmospheric neutrino anomaly and for studies of atmospheric neutrino and antineutrino fluxes. The experimental method is based on the observation of the reduced effective lifetime of the negative muons, stopped in matter, as compared to the lifetime of positive muons. Avoiding the difficulties and the systematic errors of magnetic spectrometers, results are obtained with high accuracy, indicating a decrease of the muon charge ratio from 1.30 (at 0.87 GeV/c) to 1.15 (at 0.24 GeV/c). Super-Kamiokande and other experiments find that the ratio of muonic to electronic neutrinos is much smaller than the theoretical production, the effect depending on the incidence angle of the neutrinos. The interpretation of such so-called 'neutrino anomaly' in terms of neutrino oscillations is based on theoretical predictions of the fluxes of the neutrinos of different flavour, based on different hadronic interaction models. A possibility to verify such models is to compare the theoretical predictions for muon flux, which plays a key role in neutrino chain, with the experimental data. Thus, the ratio of the flux of positive to negative muons could provide a sensitive test for models regarding muon and neutrino production. The WILLI detector is a suitable instrument for further investigation of the modulation of muon charge ratio and the neutrino fluxes by the geomagnetic cut-off. The details about the geomagnetic influence have not been explored using the observation of muons with different angles of incidence in zenithal and azimuthal plane. The WILLI detector is now modified in a rotatable set-up, which will allow

  2. Morphometric analysis of the arteries of Willis Polygon

    Directory of Open Access Journals (Sweden)

    Canaz Huseyin

    2018-03-01

    Full Text Available Objective: Willis polygon forms the basis of the arterial circulation of the cerebrum. Willis polygon is a vascular structure whom variations are not rare. Knowledge of the anatomy and preservation of its integrity is crucial for performing neurovascular surgery and intracranial tumour surgery. Because of the important vascular and neurological structures, approaches to this region are considered extremely risky. One of the main variations in-person basis is the diameter differences of the arteries, which forms Willis polygon, between the left and right hemispheres. About structure and variations, studies of Rhoton and Yasargil had formed the touchstone. Our aim is to contribute to the literature and clinical studies, to be done in the future, by comparing our results with previous studies about variations and morphometric features of Willis polygon.

  3. Heritability of circle of Willis variations in families with intracranial aneurysms.

    Directory of Open Access Journals (Sweden)

    Mayte Sánchez van Kammen

    Full Text Available Intracranial aneurysms more often occur in the same arterial territory within families. Several aneurysm locations are associated with specific circle of Willis variations. We investigated whether the same circle of Willis variations are more likely to occur in first-degree relatives than in unrelated individuals.We assessed four circle of Willis variations (classical, A1-asymmetry, incomplete posterior communicating artery and fetal circulation in two independent groups of families with familial aneurysms and ≥2 first-degree relatives with circle of Willis imaging on MRA/CTA. In each (index family we determined the proportion of first-degree relatives with the same circle of Willis variation as the proband and compared it to the proportion of first-degree relatives of a randomly selected unrelated (comparison family who had the same circle of Willis variation as the index family's proband. Concordance in index families and comparison families was compared with a conditional logistic events/trials model. The analysis was simulated 1001 times; we report the median concordances, odds ratios (ORs, and 95% confidence intervals (95%CI. The groups were analysed separately and together by meta-analysis.We found a higher overall concordance in circle of Willis configuration in index families than in comparison families (meta-analysis, 244 families: OR 2.2, 95%CI 1.6-3.0 mostly attributable to a higher concordance in incomplete posterior communicating artery (meta-analysis: OR 2.8, 95%CI 1.8-4.3. No association was found for the other three circle of Willis variations.In two independent groups of families with familial aneurysms, the incomplete PcomA variation occurred more often within than between families suggesting heritability of this circle of Willis variation. Further studies should investigate genetic variants associated with circle of Willis formation.

  4. Reciprocity, passivity and causality in Willis materials.

    Science.gov (United States)

    Muhlestein, Michael B; Sieck, Caleb F; Alù, Andrea; Haberman, Michael R

    2016-10-01

    Materials that require coupling between the stress-strain and momentum-velocity constitutive relations were first proposed by Willis (Willis 1981 Wave Motion 3 , 1-11. (doi:10.1016/0165-2125(81)90008-1)) and are now known as elastic materials of the Willis type, or simply Willis materials. As coupling between these two constitutive equations is a generalization of standard elastodynamic theory, restrictions on the physically admissible material properties for Willis materials should be similarly generalized. This paper derives restrictions imposed on the material properties of Willis materials when they are assumed to be reciprocal, passive and causal. Considerations of causality and low-order dispersion suggest an alternative formulation of the standard Willis equations. The alternative formulation provides improved insight into the subwavelength physical behaviour leading to Willis material properties and is amenable to time-domain analyses. Finally, the results initially obtained for a generally elastic material are specialized to the acoustic limit.

  5. Diagnosis in Prader-Willi syndrome.

    OpenAIRE

    Chu, C E; Cooke, A; Stephenson, J B; Tolmie, J L; Clarke, B; Parry-Jones, W L; Connor, J M; Donaldson, M D

    1994-01-01

    Thirty one patients with the putative diagnosis of Prader-Willi syndrome were reassessed clinically and by DNA analysis. Eleven patients were judged not to have Prader-Willi syndrome and 20 to have the condition. This was confirmed by DNA analysis in all but one case. The diagnosis of Prader-Willi syndrome, especially in early infancy, should be made with caution unless confirmed by molecular genetic studies.

  6. [Rapid first-tier genetic diagnosis in patients with Prader-Willi syndrome].

    Science.gov (United States)

    Ács, Orsolya Dóra; Péterfia, Bálint; Hollósi, Péter; Haltrich, Irén; Sallai, Ágnes; Luczay, Andrea; Buiting, Karin; Horsthemke, Bernhard; Török, Dóra; Szabó, András; Fekete, György

    2018-01-01

    According to the international literature, DNA methylation analysis of the promoter region of SNRPN locus is the most efficient way to start genetic investigation in patients with suspected Prader-Willi syndrome. Our aim was to develop a simple, reliable first-tier diagnosis to confirm Prader-Willi syndrome, therefore to compare our self-designed simple, cost-efficient high-resolution melting analysis and the most commonly used methylation-specific multiplex ligation-dependent probe amplification to confirm Prader-Willi syndrome. We studied 17 clinically suspected Prader-Willi syndrome children and their DNA samples. With self-designed primers, bisulfite-sensitive polymerase chain reaction, high-resolution melting analysis and, as a control, methylation-specific multiplex ligation-dependent probe amplification were performed. Prader-Willi syndrome was genetically confirmed in 6 out of 17 clinically suspected Prader-Willi syndrome patients. The results of high-resolution melting analysis and methylation-specific multiplex ligation-dependent probe amplification were equivalent in each case. Using our self-designed primers and altered bisulfite-specific PCR conditions, high-resolution melting analysis appears to be a simple, fast, reliable and effective method for primarily proving or excluding clinically suspected Prade-Willi syndrome cases. Orv Hetil. 2018; 159(2): 64-69.

  7. Anatomical variations of the circle of Willis and cerebrovascular accidents in transitional Albania

    Directory of Open Access Journals (Sweden)

    Edlira Harizi (Shemsi

    2015-12-01

    Full Text Available Aim: The purpose of this study was twofold: i in a case-control design, to determine the relationship between anatomical variations of the circle of Willis and cerebrovascular accidents; ii to assess the association between anatomical variations of the circle of Willis and aneurisms among patients with subarachnoid hemorrhage. Methods: A case-control study was conducted in Albania in 2013-2014, including 100 patients with subarachnoid hemorrhage and 100 controls (individuals without cerebrovascular accidents. Patients with subarachnoid hemorrhage underwent a CT angiography procedure, whereas individuals in the control group underwent a magnetic resonance angiography procedure. Binary logistic regression was used to assess the association between cerebrovascular accidents and the anatomical variations of the circle of Willis. Conversely, Fisher’s exact test was used to compare the prevalence of aneurisms between subarachnoid hemorrhage patients with and without anatomical variations of the circle of Willis. Results: Among patients, there were 22 (22% cases with anatomical variations of the circle of Willis compared with 10 (10% individuals in the control group (P=0.033. There was no evidence of a statistically significant difference in the types of the anatomical variations of the circle of Willis between patients and controls (P=0.402. In age- and-sex adjusted logistic regression models, there was evidence of a significant positive association between cerebrovascular accidents and the anatomical variations of the circle of Willis (OR=1.87, 95%CI=1.03-4.68, P=0.048. Within the patients’ group, of the 52 cases with aneurisms, there were 22 (42.3% individuals with anatomical variations of the circle of Willis compared with no individuals with anatomical variations among the 48 patients without aneurisms (P<0.001. Conclusion: This study provides useful evidence on the association between anatomical variations of the circle of Willis and

  8. Migraine without aura is not associated with incomplete circle of Willis

    DEFF Research Database (Denmark)

    Ezzatian-Ahar, Shabnam; Amin, Faisal Mohammad; Obaid, Hayder Ghani

    2014-01-01

    the prevalence of incomplete circle of Willis in migraineurs and controls. In the present study we compared the prevalence of incomplete circle of Willis in female migraine patients without aura to female healthy non-migraine controls.Using 3-Tesla magnetic resonance angiography we recorded three...

  9. Case report: severe asymptomatic hyponatremia in Prader-Willi Syndrome.

    Science.gov (United States)

    Landau, Daniel; Hirsch, Harry J; Gross-Tsur, Varda

    2016-02-18

    Prader-Willi syndrome is a complex neurogenetic, multisystem disorder. Despite the variable endocrine abnormalities and hypothalamic-pituitary axis dysfunction, hyponatremia has been reported in only a few PWS patients. In previously reported PWS individuals, hyponatremia was associated with abnormal fluid intake or during desmopressin treatment. We describe an infant with Prader-Willi syndrome who had severe, prolonged asymptomatic hyponatremia without a history of excessive fluid intake or desmopressin treatment. We compare the findings with those of the few other reported cases and describe, for the first time, results of a hypertonic saline infusion test and studies of adrenal cortical function. Hyponatremia should be suspected in children with Prader-Willi syndrome, especially in infants with severe failure to thrive. Further studies are needed to determine the pathophysiology of hyponatremia in this syndrome.

  10. Migraine with aura is associated with an incomplete circle of willis: results of a prospective observational study.

    Directory of Open Access Journals (Sweden)

    Brett Cucchiara

    Full Text Available To compare the prevalence of an incomplete circle of Willis in patients with migraine with aura, migraine without aura, and control subjects, and correlate circle of Willis variations with alterations in cerebral perfusion.Migraine with aura, migraine without aura, and control subjects were prospectively enrolled in a 1∶1∶1 ratio. Magnetic resonance angiography was performed to examine circle of Willis anatomy and arterial spin labeled perfusion magnetic resonance imaging to measure cerebral blood flow. A standardized template rating system was used to categorize circle of Willis variants. The primary pre-specified outcome measure was the frequency of an incomplete circle of Willis. The association between circle of Willis variations and cerebral blood flow was also analyzed.170 subjects were enrolled (56 migraine with aura, 61 migraine without aura, 53 controls. An incomplete circle of Willis was significantly more common in the migraine with aura compared to control group (73% vs. 51%, p = 0.02, with a similar trend for the migraine without aura group (67% vs. 51%, p = 0.08. Using a quantitative score of the burden of circle of Willis variants, migraine with aura subjects had a higher burden of variants than controls (p = 0.02. Compared to those with a complete circle, subjects with an incomplete circle had greater asymmetry in hemispheric cerebral blood flow (p = 0.05. Specific posterior cerebral artery variants were associated with greater asymmetries of blood flow in the posterior cerebral artery territory.An incomplete circle of Willis is more common in migraine with aura subjects than controls, and is associated with alterations in cerebral blood flow.

  11. Genetics Home Reference: Prader-Willi syndrome

    Science.gov (United States)

    ... caused by a phenomenon called genomic imprinting. Most cases of Prader-Willi syndrome (about 70 percent) occur when a segment of ... More about Mutations and Health Inheritance Pattern Most cases of Prader-Willi syndrome are not inherited, particularly those caused by a ...

  12. Thomas Willis: the faculties and his two cognitive frameworks.

    Science.gov (United States)

    McNabb, Jody

    2014-11-01

    Thomas Willis' 1664 study The anatomy of the brain is widely regarded as one of the first clinical studies of the brain. In Theanatomy, Thomas Willis explicitly connected the cognitive faculties and the nerves. Willis' later, 1672 work, The two discourses concerning the soul of brutes, severely undermined the materialism of Willis' first study: he affirmed dualism and cognitive immateriality; changed the anatomical locations of cognition; and reasserted a division between the rational and sensitive souls. His exact motive to return to orthodoxy is unclear, but contemporary scholarship of Willis has compounded the confusion with by relying predominantly on The soul of brutes instead of The anatomy. We trace Willis' career and examine his methodological practices, which help explain the historical practices and pressures. A closer examination of Willis' Anatomy of the brain reveals a much more materialistic account of the brain, the faculties, and nervous system. In this article, we present our own analysis of Willis' concept of rationality in the Anatomy and explain its importance for nervous physiology and understanding the analytic techniques for first defining faculty localizations. We then explain the role of the imagination and the immortal soul in the rearticulated anatomical concepts from The soulof brutes. Copyright © 2014 Elsevier Inc. All rights reserved.

  13. Prader-Willi Syndrome: Two Case Studies.

    Science.gov (United States)

    Bahling, Elizabeth F.

    1979-01-01

    Prader-Willi Syndrome, also called "the eating disease", is a low-incidence handicap which cannot be diagnosed in infancy. Most adults reported in the literature are institutionalized and profoundly retarded. A study of the diagnosis and intervention of two Prader-Willi Syndrome children is presented. (Author/JKS)

  14. Treatment of a Prader-Willi Patient with Recurrent Catatonia

    Directory of Open Access Journals (Sweden)

    Hana M. Poser

    2015-01-01

    Full Text Available Prader-Willi is a genetic disorder characterized by neonatal hypotonia, hyperphagia, short stature, hypogonadism, and mental delay. This disorder can result from multiple mechanisms, most commonly a deletion of paternal chromosome 15, leaving a single maternally derived chromosome 15. Individuals who have a maternal uniparental disomy of chromosome 15 have a higher risk for developing psychosis compared to other forms of Prader-Willi. The following report details the treatment course of a 24-year-old female with Prader-Willi and recurrent catatonia. The patient initially had a positive lorazepam challenge test but subsequently failed treatment with benzodiazepines. She then received eight electroconvulsive therapy (ECT treatments after which she showed improvement from initial catatonic state. However, the resolution in her symptoms did not follow a linear course but would show periods of improvement followed by a return of catatonic features. This case provides an example of the complexity of treatment of a patient with a genetic disorder and recurrent catatonia.

  15. William J. Willis (1932-2012)

    CERN Multimedia

    2012-01-01

    It is with great sadness that we learned of the passing of our colleague of many years, Bill Willis, who died on 1 November after a short illness.   Active in physics until his very last days, Bill’s career spanned more than 50 years at the forefront of particle physics. After his early career in weak interaction studies using bubble chambers in the USA, he was persuaded to join CERN in 1973, where he was introduced by Jack Steinberger as "the cleverest physicist I've ever met". He was attracted by the physics potential of the CERN ISR to which he brought a vision of a new detector concept – a 4π facility with charged and neutral particle detection capability, which he called the "Impactometer". Its possibility of measuring "missing energy" and the importance of direct lepton detection were prescient concepts of immense discovery potential. The first incarnation of the "Impactometer" ...

  16. Decline of CSF orexin (hypocretin) levels in Prader-Willi syndrome.

    Science.gov (United States)

    Omokawa, Mayu; Ayabe, Tadayuki; Nagai, Toshiro; Imanishi, Aya; Omokawa, Ayumi; Nishino, Seiji; Sagawa, Yohei; Shimizu, Tetsuo; Kanbayashi, Takashi

    2016-05-01

    Prader-Willi syndrome is a congenital neurodevelopmental disorder resulting from deletion of the paternal copies of genes within the chromosome region 15q11-q13. Patients with Prader-Willi syndrome often exhibit excessive daytime sleepiness, excessive appetite, and obesity. As is the case in narcolepsy, orexin (hypocretin) may be responsible for these symptoms. However, reports showing cerebrospinal fluid orexin levels in Prader-Willi syndrome patients have been limited. The aim of this study was to examine the relationship between the characteristic symptoms of Prader-Willi syndrome and cerebrospinal fluid orexin levels. We clinically identified 14 Prader-Willi syndrome patients and examined their cerebrospinal fluid orexin levels. A total of 12 patients with a 15q11-q13 deletion and two patients with maternal uniparental disomy of chromosome 15 were identified. A total of 37 narcoleptic patients and 14 idiopathic hypersomnia patients were recruited for comparison. Cerebrospinal fluid orexin levels (median [25-75 percentiles]) in the 14 Prader-Willi syndrome patients were intermediate (192 [161-234.5] pg/ml), higher than in the narcoleptic patients, but lower than in the idiopathic hypersomnia patients. Body mass index of the Prader-Willi syndrome patients was higher than in the narcoleptic and idiopathic hypersomnia patients. There was also a negative correlation between Epworth sleepiness scale scores and orexin levels in Prader-Willi syndrome patients. Decreased cerebrospinal fluid orexin levels in Prader-Willi syndrome may play an important role in severity of obesity and excessive daytime sleepiness. © 2016 Wiley Periodicals, Inc.

  17. Willy K. TONUI

    African Journals Online (AJOL)

    Transmission Blocking Vaccine Studies in Leishmaniasis. Willy K. ... New strategies for control of leishmaniases are required as chemotherapy using antimonial drugs is pro- longed .... taining blood, lxl0' amastigotes and antibodies or con-.

  18. The heterogeneity of craniofacial morphology in Prader-Willi patients.

    Science.gov (United States)

    Belengeanu, D; Bratu, Cristina; Stoian, Monica; Motoc, A; Ormerod, Eli; Podariu, Angela Codruţa; Farcaş, Simona; Andreescu, Nicoleta

    2012-01-01

    Prader-Willi syndrome is a complex genetic disorder with narrow spectrum of facial phenotypic signs, which make the clinical diagnosis difficult in some cases. There are several reports describing the craniofacial appearance of Prader-Willi patients, but there are only a few cephalometric studies for these patients. In this study were included 18 patients with Prader-Willi syndrome and a control group of 18 subjects of both sexes selected based on specific criteria. The cephalometric radiographs of the patients were taken using the standardized technique with centric teeth in occlusion and lips in relaxed position. Angular, horizontal and linear measurements were analyzed for the study group and for the control group. We established that in Prader-Willi patients, there is a decrease of the majority of parameters but the degree of this reduction varies widely between patients and clinically typical facies not always have smaller measurements which can be found in an unusual facies. Facial dysmorphism in Prader-Willi patients varies a group ranging from miss proportions that do not alter the facial architecture as regard of facial typology, skeletal class and pattern of development to a severe disturbance of those. There is a degree of clinical heterogeneity between subjects with Prader-Willi syndrome on clinical evaluation and cephalometric study confirms the heterogeneity for this patients. Because the identification of smaller dimensions for majority of parameters in children and adults, the possibility of developmental delay or growth retardation delay can be excluded. These findings are important for the orthodontist for optimum timing of orthodontic management of patients with Prader-Willi syndrome.

  19. New onset epilepsy in Prader-Willi syndrome: semiology and literature review.

    Science.gov (United States)

    Benson, Leslie A; Maski, Kiran P; Kothare, Sanjeev V; Bourgeois, Blaise F

    2010-10-01

    Prader-Willi syndrome is a chromosomal disorder caused by absence of expression of the paternal active genes in the 15q11∼q13 chromosome region; it is associated with an increased incidence of epilepsy and narcolepsy. Presented here is the case of a 2.5-year-old boy with Prader-Willi syndrome and a history of neonatal superior sagittal sinus thrombosis with new onset of atonic seizures with electrographic onset from the parasagittal region. It is postulated that microscarring from neonatal venous sinus thrombosis, history of febrile seizures, and Prader-Willi syndrome are factors predisposing him to epilepsy. The importance of video electroencephalography with electromyography electrodes is emphasized for Prader-Willi syndrome patients with drop episodes, to differentiate cataplexy from seizures. This being a novel report of a Prader-Willi syndrome patient with atonic seizures, the literature on seizure semiology among patients with Prader-Willi syndrome is reviewed. Copyright © 2010 Elsevier Inc. All rights reserved.

  20. A Tribute to Dr. Willy Lens

    Directory of Open Access Journals (Sweden)

    Maarten Vansteenkiste

    2016-07-01

    Full Text Available Dr. Willy Lens, born on December 10th, 1943, passed away on August 29th, 2014. With his passing, the motivation community has lost a seminal member, a mentor, and a friend. Dr. Lens – a Fellow of the Association for Psychological Science and Founding Fellow of the American Educational Research Association – made fundamental contributions to the study of motivation both through his own work and through his caring and thoughtful mentorship of a large community of scholars. With this tribute, we want to honor Dr. Willy Lens’ significance to psychology and education as well as his positive influence, both personally and professionally, on the lives of dozens of scholars. With his contagious enthusiasm and caring mentorship, Willy was an example for our academic community and with this tribute we express our gratitude for the privilege to have collaborated with him.

  1. Causes of death in Prader-Willi syndrome: Prader-Willi Syndrome Association (USA) 40-year mortality survey.

    Science.gov (United States)

    Butler, Merlin G; Manzardo, Ann M; Heinemann, Janalee; Loker, Carolyn; Loker, James

    2017-06-01

    Prader-Willi syndrome (PWS) is a rare, complex, neurodevelopmental genetic disorder that is associated with hyperphagia and morbid obesity in humans and leads to a shortened life expectancy. This report summarizes the primary causes of death and evaluates mortality trends in a large cohort of individuals with PWS. The US Prader-Willi Syndrome Association (PWSA (USA)) syndrome-specific database of death reports was collected through a cursory bereavement program for PWSA (USA) families using a brief survey created in 1999. Causes of death were descriptively characterized and statistically examined using Cox proportional hazards. A total of 486 deaths were reported (263 males, 217 females, 6 unknown) between 1973 and 2015, with mean age of 29.5 ± 16 years (2 months-67 years); 70% occurred in adulthood. Respiratory failure was the most common cause, accounting for 31% of all deaths. Males were at increased risk for presumed hyperphagia-related accidents/injuries and cardiopulmonary factors compared to females. PWS maternal disomy 15 genetic subtype showed an increased risk of death from cardiopulmonary factors compared to the deletion subtype. These findings highlight the heightened vulnerability to obesity and hyperphagia-related mortality in PWS. Future research is needed to address critical vulnerabilities such as gender and genetic subtype in the cause of death in PWS.Genet Med advance online publication 17 November 2016.

  2. Prader-Willi Syndrome Association

    Science.gov (United States)

    ... everyone will be talking about. Join the many families and individuals that are part of the PWS community this year in Orlando, FL from November ... of autism spectrum disorders in children with Prader-Willi syndrome pwsa | Jun ...

  3. Willy Brandt and Ostpolitik

    National Research Council Canada - National Science Library

    1976-01-01

    .... Emerging superpower status allowed Moscow to tighten control over its satellite states. Willy Brandt cites his first-hand observation of the 1961 building of the Berlin Wall as the act which ended his illusions over U.S...

  4. Presence of anatomical variations of the circle of Willis in patients undergoing surgical treatment for ruptured intracranial aneurysms

    Directory of Open Access Journals (Sweden)

    Stojanović Nebojša

    2009-01-01

    Full Text Available Background/Aim. The presence of aneurysmal changes on the brain blood vessels has been subject to numerous research. This study investigated the relation between ruptured aneurysms and anatomical configuration of the Circle of Willis, with the purpose to obtain an insight into their mutual connection. Methods. The analysis included 114 patients suffering from ruptured intracranial aneurysms. Preoperative cerebral angiography was performed and compared with the intraoperative findings in order to attain a precise insight into morphological changes occurring on the circle of Willis. Results. The prevalence of asymmetrical Willis in the whole group of patients was 64%. Within the group of patients suffering from multiple aneurysms, the presence of asymmetrical Willis' circle was 75.7%. The highest incidence of the asymmetrical Circle of Willis was found among patients with aneurysmal rupture detected at the anterior comunicative artery (ACoA site (72.7% among cases with solitary and 100% among those with multiple aneurysms. Morphological changes on the A1 segment of ACoA were observed in 50 (44% cases, with higher incidence found on the right side (60%. When comparing location of ruptured aneurysms between genders, a statistically significant prevalence of the ruptured aneurisms on ACoA was present in men, whereas women showed higher incidence of ruptured aneurysms on interior cartid artery (ICA site (p < 0.01. The linkage between aneurysms with hypoplasia of the A1 segment of ACA and decreasing of the angle at which segments A1 and A2 join suggests the relationship between their onset, corresponding configuration type of Willis and subsequent hemodynamic changes. Conclusion. High incidence of asymmetry of Willis circle in the group of patients with ruptured aneurysms imply association of asymmetrical configuration and disorder in haemodynamic relations with forming and rupture of intracranial aneurysms.

  5. Willis H Carrier

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 17; Issue 2. Willis H. Carrier - Father of Air Conditioning. R V Simha. General Article Volume 17 Issue 2 February 2012 pp 117-138. Fulltext. Click here to view fulltext PDF. Permanent link: https://www.ias.ac.in/article/fulltext/reso/017/02/0117-0138 ...

  6. Life Satisfaction among Mothers of Individuals with Prader-Willi Syndrome

    Science.gov (United States)

    Shivers, Carolyn M.; Leonczyk, Caroline L.; Dykens, Elisabeth M.

    2016-01-01

    Mothers of individuals with Prader-Willi syndrome (PWS) often experience numerous stressors, even when compared to mothers of children with other intellectual and developmental disabilities. Despite this, these mothers show great variability in self-reported life satisfaction. Using data from a longitudinal study of individuals with PWS and their…

  7. Using Willie's Acid-Base Box for Blood Gas Analysis

    Science.gov (United States)

    Dietz, John R.

    2011-01-01

    In this article, the author describes a method developed by Dr. William T. Lipscomb for teaching blood gas analysis of acid-base status and provides three examples using Willie's acid-base box. Willie's acid-base box is constructed using three of the parameters of standard arterial blood gas analysis: (1) pH; (2) bicarbonate; and (3) CO[subscript…

  8. What Causes Prader-Willi Syndrome?

    Science.gov (United States)

    ... a fundamental role in regulating hunger and fullness. Maternal uniparental disomy (pronounced yoo-nuh-puh-REN-tl ... 2018). Prader-Willi syndrome and early-onset morbid obesity NIH rare disease consortium: A review of natural ...

  9. Circle of willis and its variations; morphometric study in adult human cadavers

    OpenAIRE

    Raghavendra, Shirol VS, Daksha Dixit, Anil Kumar Reddy Y, Desai SP

    2014-01-01

    Background and Objectives: Circle of Willis plays a vital role in collateral circulation and redistribution of blood to all areas of the brain. Variation in circle of Willis is known to cause grave disorders like cerebrovascular disorders, subarachnoid haemorrhage, cerebral aneurysm and schizophrenia. The objectives of the present study are to study the formation and branching pattern of circle of Willis and also to study the distribution of variations. MATERIALS & Methods: The study was cond...

  10. Face Discrimination Skills in Prader-Willi Syndrome and Autism Spectrum Disorder

    Science.gov (United States)

    Feldman, Benjamin H.; Dimitropoulos, Anastasia

    2014-01-01

    Individuals with Prader-Willi Syndrome (PWS) are at risk for autism spectrum disorder (ASD), including socialization problems. The PWS chromosome 15q11-13 maternal uniparental disomy (mUPD) subtype displays greater ASD symptoms than the paternal deletion (DEL) subtype. Since interpreting faces leads to successful socialization, we compared face…

  11. Prader-Willi-like phenotypes: a systematic review of their chromosomal abnormalities.

    Science.gov (United States)

    Rocha, C F; Paiva, C L A

    2014-03-31

    Prader-Willi syndrome (PWS) is caused by the lack of expression of genes located on paternal chromosome 15q11-q13. This lack of gene expression may be due to a deletion in this chromosomal segment, to maternal uniparental disomy of chromosome 15, or to a defect in the imprinting center on 15q11-q13. PWS is characterized by hypotonia during the neonatal stage and in childhood, accompanied by a delay in neuropsychomotor development. Overeating, obesity, and mental deficiency arise later on. The syndrome has a clinical overlap with other diseases, which makes it difficult to accurately diagnose. The purpose of this article is to review the Prader-Willi-like phenotype in the scientific literature from 2000 to 2013, i.e., to review the cases of PWS caused by chromosomal abnormalities different from those found on chromosome 15. A search was carried out using the "National Center for Biotechnology Information" (www.pubmed.com) and "Scientific Electronic Library Online (www.scielo.br) databases and combinations of key words such as "Prader-Willi-like phenotype" and "Prader-Willi syndrome phenotype". Editorials, letters, reviews, and guidelines were excluded. Articles chosen contained descriptions of patients diagnosed with the PWS phenotype but who were negative for alterations on 15q11-q13. Our search found 643 articles about PWS, but only 14 of these matched with the Prader-Willi-like phenotype and with the selected years of publication (2000-2013). If two or more articles reported the same chromosomal alterations for Prader-Willi-like phenotype, the most recent was chosen. Twelve articles of 14 were case reports and 2 reported series of cases.

  12. Clinical management of behavioral characteristics of Prader–Willi syndrome

    Directory of Open Access Journals (Sweden)

    Alan Y Ho

    2010-04-01

    Full Text Available Alan Y Ho, Anastasia DimitropoulosDepartment of Psychology, Case Western Reserve University, Cleveland, OH, USAAbstract: Prader–Willi syndrome (PWS is a complex neurodevelopmental disorder caused by an abnormality on the long arm of chromosome 15 (q11–q13 that results in a host of phenotypic characteristics, dominated primarily by hyperphagia and insatiable appetite. Characteristic behavioral disturbances in PWS include excessive interest in food, skin picking, difficulty with a change in routine, temper tantrums, obsessive and compulsive behaviors, and mood fluctuations. Individuals with PWS typically have intellectual disabilities (borderline to mild/moderate mental retardation and exhibit a higher overall behavior disturbance compared to individuals with similar intellectual disability. Due to its multisystem disorder, family members, caregivers, physicians, dieticians, and speech-language pathologists all play an important role in the management and treatment of symptoms in an individual with PWS. This article reviews current research on behavior and cognition in PWS and discusses management guidelines for this disorder.Keywords: Prader–Willi syndrome; neurodevelopment, hyperphagia, disability

  13. Application of willis covered stent in the treatment of aneurysms located in the cisternal segment of the internal carotid artery: a pilot comparative study with long-term follow-up results

    International Nuclear Information System (INIS)

    Zhu Yueqi; Li Minghua; Fang Chun; Wang Wu; Zhang Peilei; Cheng Yingsheng; Tan Huaqiao; Wang Jianbo

    2010-01-01

    Objective: Complicated aneurysms located in the cisternal segment of the internal carotid artery(ICA-CSA) present unique therapeutic difficulties. This study is to discuss the feasibility of the Willis stent-graft in treating complicated ICA-CSA by comparing its effect with that of coiling therapy. Methods: Willis covered stents were employed in 19 complicated ICA-CSAs (group A), while coils were used in 17 complicated ICA-CSAs (group B). Follow-up angiography was performed to investigate aneurysm recurrence, endoleak and parent artery (PA) stenosis. Kaplan-Meier curves were constructed to compare the recurrence-free and PA stenosis-free rate in both groups. Results: Total exclusion was immediately achieved in 13 ICA-CSAs and minor endoleaks presented in 5 cases in group A. Total or near-total occlusion was achieved in 7 ICA-CSAs, subtotal occlusion in 8 and partial occlusion in 2 cases in group B after coiling. Acute thrombosis occurred in 1 patient in either group and re-hemorrhage happened in 1 patient after coiling. Follow-up angiography in group A revealed that 16 ICA-CSAs were completely isolated, with two parent arteries showing mild in-stent stenosis. Eighteen months after the procedure, Kaplan-Meier analysis showed that the recurrence-free rate was 93.3% and 50%, while the stenosis-free rate of parent artery was 87.5% and 100% in group A and in Group B, respectively. In group A and group Bthe clinical neurological symptoms were fully recovered in 9 and 9, obviously improved in 3 and 5, unchanged in 2 and 2, and aggravated in one and 0 patients, respectively. Conclusion: The implantation of Willis stent-graft is a feasible endovascular therapy for complicated ICA-CSAs. When the parent artery is very tortuous or when the risk that a main collateral branch may be wrongly covered and occluded is present, the implantation of Willis covered stent can not be taken as the treatment of first choice. (authors)

  14. Circle of willis and its variations; morphometric study in adult human cadavers

    Directory of Open Access Journals (Sweden)

    Raghavendra, Shirol VS, Daksha Dixit, Anil Kumar Reddy Y, Desai SP

    2014-04-01

    Full Text Available Background and Objectives: Circle of Willis plays a vital role in collateral circulation and redistribution of blood to all areas of the brain. Variation in circle of Willis is known to cause grave disorders like cerebrovascular disorders, subarachnoid haemorrhage, cerebral aneurysm and schizophrenia. The objectives of the present study are to study the formation and branching pattern of circle of Willis and also to study the distribution of variations. MATERIALS & Methods: The study was conducted on 50 adult brain specimens. Each brain was removed in one piece by dissection and the circle of Willis was observed for its formation, pattern and variations. Results: Among the 50 specimens studied, 28 cases (56% had a normal pattern of circle of Willis and variations were observed in the remaining 22 cases (44%. More number of variations was observed on the right side than on the left side. The most common variation observed was hypoplastic posterior communicating artery (7 cases, 31.8%. Posterior communicating artery was found to be the most variable vessel while middle cerebral artery was the least variable vessel. Interpretation and Conclusion: The results with respect to the circle of Willis and all its component arteries were consistent with the results in the available literature. The only exception was the increased incidence of absence of both the anterior and posterior communicating arteries. This finding is of clinical significance to neurologists and neurosurgeons in this geographical location of north Karnataka. A higher incidence of variations in the communicating arteries is likely to manifest as a higher incidence in disorders like migraine, schizophrenia and cerebrovascular disorders due to compromised collateral circulation and poor redistribution of blood.

  15. MEMORIAL SYMPOSIUM:
    Willi Jentschke

    CERN Multimedia

    CERN. Geneva

    2002-01-01

    - Welcome by L. Maiani - Message from DESY by E. Lohrmann - Willi Jentschke by H. Schopper - The Neutral Currents by M. Veltman and D. Perkins - The ISR in Jentschke's time by K. Johnsen - Some recollections of Jentschke by K. WinterNote: Participants are cordially invited to drinks at 17h.30 following the symposium

  16. A Mindfulness-Based Health Wellness Program for an Adolescent with Prader-Willi Syndrome

    Science.gov (United States)

    Singh, Nirbhay N.; Lancioni, Giulio E.; Singh, Ashvind N.; Winton, Alan S. W.; Singh, Judy; McAleavey, Kristen M.; Adkins, Angela D.

    2008-01-01

    Individuals with Prader-Willi syndrome have hyperphagia, a characteristic eating disorder defined by a marked delay in the satiety response when compared to controls. This eating disorder has been particularly difficult to control. The authors taught and evaluated effectiveness of regular exercise alone, regular exercise plus healthy eating, and…

  17. A Characterization of Movement Skills in Obese Children with and without Prader-Willi Syndrome

    Science.gov (United States)

    Lam, Melanie Y.; Rubin, Daniela A.; Duran, Andrea T.; Chavoya, Frank A.; White, Elizabeth; Rose, Debra J.

    2016-01-01

    Purpose: The aim of this study was twofold: (a) to measure and compare motor proficiency in obese children with Prader-Willi syndrome (OB-PWS) to that in obese children without PWS (OB), and (b) to compare motor proficiency in OB-PWS and OB to normative data. Method: Motor proficiency was measured using the Bruininks-Oseretsky Test of Motor…

  18. Behavioral and emotional manifestations in a child with Prader-Willi syndrome.

    Science.gov (United States)

    Mohapatra, Satyakam; Panda, Udit Kumar

    2016-04-25

    Prader-Willi syndrome is a neurodevelopmental disorder characterized by mental retardation and distinct physical, behavioral, and psychiatric features. Maladaptive behaviours, cognitive impairment, and impediments in speech and language seriously affect the early development and long-term functioning of individuals affected by the illness. We present a case of a 9-year-old child with Prader-Willi syndrome whose behavioural symptoms were treated with low-dose antipsychotic medications.

  19. Three Siblings with Prader-Willi Syndrome: Brief Review of Sleep and Prader-Willi Syndrome

    Directory of Open Access Journals (Sweden)

    Arina Bingeliene

    2015-01-01

    Full Text Available Prader-Willi syndrome (PWS is a genetic disorder characterized by short stature, mental retardation, hypotonia, functionally deficient gonads, and uncontrolled appetite leading to extreme obesity at an early age. Patients with this condition require multidisciplinary medical care, which facilitates a significant improvement in quality of life. PWS is the first human disorder to be attributed to genomic imprinting. Prevalence varies in the literature, ranging from 1 in 8,000 in the Swedish population to 1 in 54,000 in the United Kingdom. Rarely, the genetic mechanism responsible for Prader-Willi syndrome can be inherited. We report a highly unique case of three siblings who share this condition. This report describes a case of two brothers and one half sister with PWS. All three siblings have sleep-related complaints. The sister died at the age of 24 years in her sleep, with the cause of death reported as obstructive sleep apnea. The outcome was positive in both of the brothers’ cases as a result of professional medical care and specific tailored recommendations implemented by their mother. A review of the relevant literature vis-à-vis sleep and PWS is provided.

  20. Prader-Willi Disease: A Case Study.

    Science.gov (United States)

    Forbus, William R., III

    A case study focuses on the characteristics and physical management of a 15-year-old with Prader-Willi Syndrome, a birth defect associated with hypotonia, insatiable appetite, hypogonadism, central nervous system dysfunction, and abnormal growth and development . A literature review addresses studies dealing with behavior modification of obesity…

  1. Assessment of Sleep and Breathing in Adults with Prader-Willi Syndrome: A Case Control Series

    Science.gov (United States)

    Yee, Brendon J.; Buchanan, Peter R.; Mahadev, Sri; Banerjee, Dev; Liu, Peter Y.; Phillips, Craig; Loughnan, Georgina; Steinbeck, Kate; Grunstein, Ronald R.

    2007-01-01

    Objectives: Prader-Willi syndrome (PWS) is a genetic disorder (linked to chromosome 15q11-13) characterized by hypotonia and developmental delay, hyperphagia and obesity, hypersomnia and abnormal sleep, and behavioral problems. Such patients may also be at increased risk of obstructive sleep apnea (OSA), although whether this risk is explained by known risk factors has not previously been directly tested. Our aim was to compare sleep and breathing in an older group of patients with Prader-Willi syndrome with a control group—matched on the basis of age, sex, and body mass index (BMI)—in order to determine which specific features are not explained by these known confounders. Methods: Consecutive patients with PWS attending the PWS clinic at Royal Prince Alfred Hospital Sydney, Australia, were recruited. Age-, sex-, and BMI-matched controls were selected from the Sleep Investigation Unit at Royal Prince Alfred Hospital, and polysomnography-derived sleep and other parameters were compared across the groups. Results: Nineteen subjects with PWS (14 males) were included in the study. Eighteen (95 %) had a total respiratory disturbance index (TRDI) of greater than 5 events per hour, with 4 (21%) having severe obstructive sleep apnea (TRDI ≥ 30 events/hour) and 9 (47%) having evidence of obesity hypoventilation syndrome. Patients with PWS, as compared with the control group, had evidence of more nocturnal hypoxemia, with lower oxyhemoglobin saturations and percentages of sleep time at less than 80% oxyhemoglobin saturation (all p values Prader-Willi syndrome: a case control series. J Clin Sleep Med 2007;3(7):713–718. PMID:18198805

  2. Treatment of carotid siphon aneurysms by use of the Willis stent graft: an angiographic and histopathological study

    International Nuclear Information System (INIS)

    Zhu, Yue-Qi; Li, Ming-Hua; Xie, Jian; Tan, Hua-Qiao; Wang, Jian-Bo; Cheng, Ying-Sheng

    2010-01-01

    We designed a carotid siphon (CS) aneurysm model in dogs to test a new stent graft (the Willis covered stent) and compared tissue reaction over 12-month follow-up versus a comparison group with stents implanted in straight vessels. Twenty-four saccular sidewall aneurysms (group A) and 12 CS aneurysms (group B) were created surgically. A Willis stent graft was implanted in each aneurysm. Angiography was performed immediately and at 1-, 3-, 6- and 12-month post-implantation to investigate aneurysm isolation, endoleak, stent angulation, parent artery (PA) patency and restenosis. Light and scanning electron microscopy were used to identify aneurysmal sac thrombi, intima hyperplasia and endothelial progress. Immediate angiography demonstrated mild endoleak in two aneurysms and three stent angulations in group B. Follow-up at 12 months revealed resolved endoleaks, occlusion in one PA and mild stenosis in three in group B. In group A, occlusion occurred in one PA and mild stenosis in two. Light microscopy revealed new intima, and all aneurysm sacs were filled with thrombi. In group B, endothelial progress was complete at 12 months, and closely correlated with haemodynamic changes. Application of a Willis stent graft is a feasible method of treating CS aneurysms, and it exhibits a prolonged endothelial progress compared with that in straight vessels. (orig.)

  3. Three Siblings with Prader-Willi Syndrome: Brief Review of Sleep and Prader-Willi Syndrome

    OpenAIRE

    Bingeliene, Arina; Shapiro, Colin M.; Chung, Sharon A.

    2015-01-01

    Prader-Willi syndrome (PWS) is a genetic disorder characterized by short stature, mental retardation, hypotonia, functionally deficient gonads, and uncontrolled appetite leading to extreme obesity at an early age. Patients with this condition require multidisciplinary medical care, which facilitates a significant improvement in quality of life. PWS is the first human disorder to be attributed to genomic imprinting. Prevalence varies in the literature, ranging from 1 in 8,000 in the Swedish po...

  4. Absent collateral function of the circle of Willis as risk factor for ischemic stroke

    NARCIS (Netherlands)

    Hoksbergen, A. W. J.; Legemate, D. A.; Csiba, L.; Csáti, G.; Síró, P.; Fülesdi, B.

    2003-01-01

    Background. Autopsy studies show a higher prevalence of circle of Willis anomalies in brains with signs of ischemic infarction. Our goal was to examine the collateral function of the circle of Willis in ischemic stroke patients and to assess in a case-control study if a collateral deficient circle

  5. Molecular characterization of a patient presumed to have prader-willi syndrome.

    Science.gov (United States)

    Falaleeva, Marina; Sulsona, Carlos R; Zielke, Horst R; Currey, Kathleen M; de la Grange, Pierre; Aslanzadeh, Vahid; Driscoll, Daniel J; Stamm, Stefan

    2013-01-01

    Prader-Willi syndrome (PWS) is caused by the loss of RNA expression from an imprinted region on chromosome 15 that includes SNRPN, SNORD115, and SNORD116. Currently, there are no mouse models that faithfully reflect the human phenotype and investigations rely on human post-mortem material. During molecular characterization of tissue deposited in a public brain bank from a patient diagnosed with Prader-Willi syndrome, we found RNA expression from SNRPN, SNORD115, and SNORD116 which does not support a genetic diagnosis of Prader-Willi syndrome. The patient was a female, Caucasian nursing home resident with history of morbid obesity (BMI 56.3) and mental retardation. She died at age of 56 from pulmonary embolism. SNORD115 and SNORD116 are unexpectedly stable in post mortem tissue and can be used for post-mortem diagnosis. Molecular characterization of PWS tissue donors can confirm the diagnosis and identify those patients that have been misdiagnosed.

  6. Severe tooth wear in Prader-Willi syndrome. A case-control study.

    Science.gov (United States)

    Saeves, Ronnaug; Espelid, Ivar; Storhaug, Kari; Sandvik, Leiv; Nordgarden, Hilde

    2012-05-28

    Prader-Willi syndrome (PWS) is a rare complex multsystemic genetic disorder characterized by severe neonatal hypotonia, endocrine disturbances, hyperphagia and obesity, mild mental retardation, learning disabilities, facial dysmorphology and oral abnormalities. The purpose of the present study was to explore the prevalence of tooth wear and possible risk factors in individuals with Prader-Willi syndrome. Forty-nine individuals (6-40 years) with PWS and an age- and sex-matched control group were included. Tooth wear was evaluated from dental casts and intraoral photographs and rated by four examiners using the Visual Erosion Dental Examination (VEDE) scoring system and the individual tooth wear index IA. In accordance with the VEDE scoring system, tooth wear was also evaluated clinically. Whole saliva was collected. Mean VEDE score was 1.70 ± 1.44 in the PWS group and 0.46 ± 0.36 in the control group (p Prader-Willi syndrome. There is therefore considerable need for prosthodontic rehabilitation in young adults with PWS.

  7. Periodontal disease in a patient with Prader-Willi syndrome: a case report

    Directory of Open Access Journals (Sweden)

    Kitamura Masahiro

    2011-07-01

    Full Text Available Abstract Introduction Prader-Willi syndrome is a complex genetic disease caused by lack of expression of paternally inherited genes on chromosome 15q11-q13. The prevalence of Prader-Willi syndrome is estimated to be one in 10,000 to 25,000. However, descriptions of the oral and dental phenotype are rare. Case presentation We describe the clinical presentation and periodontal findings in a 20-year-old Japanese man with previously diagnosed Prader-Willi syndrome. Clinical and radiographic findings confirmed the diagnosis of periodontitis. The most striking oral findings were anterior open bite, and crowding and attrition of the lower first molars. Periodontal treatment consisted of tooth-brushing instruction and scaling. Home care involved recommended use of adjunctive chlorhexidine gel for tooth brushing twice a week and chlorhexidine mouthwash twice daily. Gingival swelling improved, but further treatment will be required and our patient's oral hygiene remains poor. The present treatment of tooth-brushing instruction and scaling every three weeks therefore only represents a temporary solution. Conclusions Rather than being a direct result of genetic defects, periodontal diseases in Prader-Willi syndrome may largely result from a loss of cuspid guidance leading to traumatic occlusion, which in turn leads to the development of periodontal diseases and dental plaque because of poor oral hygiene. These could be avoided by early interventions to improve occlusion and regular follow-up to monitor oral hygiene. This report emphasizes the importance of long-term follow-up of oral health care by dental practitioners, especially pediatric dentists, to prevent periodontal disease and dental caries in patients with Prader-Willi syndrome, who appear to have problems maintaining their own oral health.

  8. Periodontal disease in a patient with Prader-Willi syndrome: a case report.

    Science.gov (United States)

    Yanagita, Manabu; Hirano, Hiroyuki; Kobashi, Mariko; Nozaki, Takenori; Yamada, Satoru; Kitamura, Masahiro; Murakami, Shinya

    2011-07-28

    Prader-Willi syndrome is a complex genetic disease caused by lack of expression of paternally inherited genes on chromosome 15q11-q13. The prevalence of Prader-Willi syndrome is estimated to be one in 10,000 to 25,000. However, descriptions of the oral and dental phenotype are rare. We describe the clinical presentation and periodontal findings in a 20-year-old Japanese man with previously diagnosed Prader-Willi syndrome. Clinical and radiographic findings confirmed the diagnosis of periodontitis. The most striking oral findings were anterior open bite, and crowding and attrition of the lower first molars. Periodontal treatment consisted of tooth-brushing instruction and scaling. Home care involved recommended use of adjunctive chlorhexidine gel for tooth brushing twice a week and chlorhexidine mouthwash twice daily. Gingival swelling improved, but further treatment will be required and our patient's oral hygiene remains poor. The present treatment of tooth-brushing instruction and scaling every three weeks therefore only represents a temporary solution. Rather than being a direct result of genetic defects, periodontal diseases in Prader-Willi syndrome may largely result from a loss of cuspid guidance leading to traumatic occlusion, which in turn leads to the development of periodontal diseases and dental plaque because of poor oral hygiene. These could be avoided by early interventions to improve occlusion and regular follow-up to monitor oral hygiene. This report emphasizes the importance of long-term follow-up of oral health care by dental practitioners, especially pediatric dentists, to prevent periodontal disease and dental caries in patients with Prader-Willi syndrome, who appear to have problems maintaining their own oral health.

  9. Cardiac evaluation in children with Prader-Willi syndrome.

    NARCIS (Netherlands)

    Marcus, K.A.; Alfen-van der Velden, J. van; Otten, B.J.; Weijers, G.; Yntema, H.G.; Korte, C.L. de; Kapusta, L.

    2012-01-01

    AIM: To assess cardiac anatomy and myocardial systolic function in children with Prader-Willi syndrome (PWS). METHODS: Physical examination, electrocardiographic (ECG) recordings and transthoracic echocardiograms including two-dimensional speckle tracking echocardiography (2DSTE) were performed and

  10. DQE of wireless digital detectors: Comparative performance with differing filtration schemes

    International Nuclear Information System (INIS)

    Samei, Ehsan; Murphy, Simon; Christianson, Olav

    2013-01-01

    Purpose: Wireless flat panel detectors are gaining increased usage in portable medical imaging. Two such detectors were evaluated and compared with a conventional flat-panel detector using the formalism of the International Electrotechnical Commission (IEC 62220-1) for measuring modulation transfer function (MTF), normalized noise power spectrum (NNPS), and detective quantum efficiency (DQE) using two different filtration schemes.Methods: Raw images were acquired for three image receptors (DRX-1C and DRX-1, Carestream Health; Inc., Pixium 4600, Trixell) using a radiographic system with a well-characterized output (Philips Super80 CP, Philips Healthcare). Free in-air exposures were measured using a calibrated radiation meter (Unfors Mult-O-Meter Type 407, Unfors Instruments AB). Additional aluminum filtration and a new alternative combined copper-aluminum filtration were used to conform the x ray output to IEC-specified beam quality definitions RQA5 and RQA9. Using the IEC 62220-1 formalism, each detector was evaluated at X N /2, X N , and 2X N , where the normal exposure level to the detector surface (X N ) was set to 8.73 μGy (1.0 mR). The prescribed edge test device was used to evaluate the MTF, while the NNPS was measured using uniform images. The DQE was then calculated from the MTF and NNPS and compared across detectors, exposures, and filtration schemes.Results: The three DR systems had largely comparable MTFs with DRX-1 demonstrating lower values above 1.0 cycles/mm. At each exposure, DRX-1C and Pixium detectors demonstrated better noise performance than that of DRX-1. Zero-frequency DQEs for DRX-1C, Pixium, and DRX-1 detectors were approximately 74%, 63%, and 38% for RQA5 and 50%, 42%, and 28% for RQA9, respectively.Conclusions: DRX-1C detector exhibited superior DQE performance compared to Pixium and DRX-1. In terms of filtration, the alternative filtration was found to provide comparable performance in terms of rank ordering of different detectors with

  11. Maladaptive Behavior Differences in Prader-Willi Syndrome Due to Paternal Deletion versus Maternal Uniparental Disomy.

    Science.gov (United States)

    Dykens, Elisabeth M.; King, Bryan H.; Cassidy, Suzanne B.

    1999-01-01

    This study compared maladaptive behavior in 23 people with Prader-Willi syndrome due to paternal deletion and in 23 age- and gender-matched subjects with maternal uniparental disomy. Controlling for IQs, the deletion cases showed significantly higher maladaptive ratings, more symptom-related distress, and more behavior problems. Findings suggest a…

  12. Willy Wonka pole pedofiil / Alar Niineväli

    Index Scriptorium Estoniae

    Niineväli, Alar

    2005-01-01

    Tim Burtoni mängufilm "Charlie ja šokolaadivabrik" Roald Dahli samanimelise raamatu järgi : Ameerika Ühendriigid 2005. Võrreldud sama raamatu 1971.a. ekraniseeringuga "Willy Wonka & the Chocolate Factory" : režissöör Mel Stuart

  13. Caracterización clínico genética del síndrome Prader Willi

    OpenAIRE

    Travieso Tellez, Anitery; Menéndez García, Reinaldo; Licourt Otero, Deysi

    2014-01-01

    Introducción: el síndrome Prader Willi es un desorden genético causado por la pérdida de genes contenidos en la región 15q11-q13 del cromosoma paterno. Objetivo: describir las características clínicas y genéticas de los pacientes con síndrome Prader Willi. Material y método: se realizó un estudio descriptivo, de corte transversal, con el universo de 15 pacientes con sospecha de síndrome Prader Willi remitidos a consulta provincial de Genética Clínica durante el año 2013. Se consideraron como ...

  14. DQE of wireless digital detectors: Comparative performance with differing filtration schemes

    Energy Technology Data Exchange (ETDEWEB)

    Samei, Ehsan [Carl E. Ravin Advanced Imaging Laboratories, Departments of Radiology, Biomedical Engineering, Physics, and Electrical and Computer Engineering, Medical Physics Graduate Program, Duke University Medical Center, Durham, North Carolina 27705 (United States); Murphy, Simon; Christianson, Olav [Medical Physics Graduate Program, Duke University, Durham, North Carolina 27705 (United States)

    2013-08-15

    Purpose: Wireless flat panel detectors are gaining increased usage in portable medical imaging. Two such detectors were evaluated and compared with a conventional flat-panel detector using the formalism of the International Electrotechnical Commission (IEC 62220-1) for measuring modulation transfer function (MTF), normalized noise power spectrum (NNPS), and detective quantum efficiency (DQE) using two different filtration schemes.Methods: Raw images were acquired for three image receptors (DRX-1C and DRX-1, Carestream Health; Inc., Pixium 4600, Trixell) using a radiographic system with a well-characterized output (Philips Super80 CP, Philips Healthcare). Free in-air exposures were measured using a calibrated radiation meter (Unfors Mult-O-Meter Type 407, Unfors Instruments AB). Additional aluminum filtration and a new alternative combined copper-aluminum filtration were used to conform the x ray output to IEC-specified beam quality definitions RQA5 and RQA9. Using the IEC 62220-1 formalism, each detector was evaluated at X{sub N}/2, X{sub N}, and 2X{sub N}, where the normal exposure level to the detector surface (X{sub N}) was set to 8.73 μGy (1.0 mR). The prescribed edge test device was used to evaluate the MTF, while the NNPS was measured using uniform images. The DQE was then calculated from the MTF and NNPS and compared across detectors, exposures, and filtration schemes.Results: The three DR systems had largely comparable MTFs with DRX-1 demonstrating lower values above 1.0 cycles/mm. At each exposure, DRX-1C and Pixium detectors demonstrated better noise performance than that of DRX-1. Zero-frequency DQEs for DRX-1C, Pixium, and DRX-1 detectors were approximately 74%, 63%, and 38% for RQA5 and 50%, 42%, and 28% for RQA9, respectively.Conclusions: DRX-1C detector exhibited superior DQE performance compared to Pixium and DRX-1. In terms of filtration, the alternative filtration was found to provide comparable performance in terms of rank ordering of different

  15. Multidisciplinary care in the intensive care unit for a patient with Prader-Willi syndrome: a dental approach.

    Science.gov (United States)

    Setti, Juliana Santiago; Pinto, Sérgio Felix; Gaetti-Jardim, Ellen Cristina; Manrique, Gustavo Rodrigues; Mendonça, José Carlos Garcia de

    2012-03-01

    Prader-Willi syndrome is a genetic neurobehavioral disease affecting children's development and resulting in obesity, reduced height, hypotonia, endocrine disorders and cognitive deficits, which may impair oral integrity. This study aims to report on a case involving a white male 15-year-old patient with Prader-Willi syndrome whose oral examination revealed bacterial plaque, gingivitis, poor occlusion, viscous salivation and multiple lip, jugal mucosa, inserted gum and tongue ulcerations. An excision biopsy revealed oral ulcerations typical of herpes, which were considered to be likely to correlate with herpes encephalitis. This result demonstrates that a large portion of the deleterious effects of Prader-Willi syndrome can be attenuated by appropriate diagnosis and early therapeutic intervention, highlighting the role of an integrated multidisciplinary team in the development of therapeutic protocols for Prader-Willi syndrome patients.

  16. Biofeedback therapy for chronic constipation in a patient with Prader-Willi syndrome.

    Science.gov (United States)

    Corral, Juan E; Kataria, Rahul; Vickers, Dawn; Koutouby, Raghad; Moshiree, Baharak

    2015-01-01

    Constipation is a common feature of Prader-Willi syndrome. Research exploring the prevalence, cause and treatment options for constipation is limited and lacks objective measurements such as anorectal manometry. We report a case of a 16-year-old lady with Prader-Willi syndrome presenting with rectal pain and constipation for 2 years despite multiple medications and weekly enemas. She also noted passive fecal incontinence that required frequent manual disimpactions. Anorectal manometry revealed an abnormal relaxation of the puborectalis and external sphincter muscles on push maneuvers suggesting dyssynergic defecation and rectal hypersensitivity. Contraction and relaxation of her pelvic muscles were recorded with electromyography. Relaxation of the puborectalis muscle improved significantly after three biofeedback sessions. Patient was successfully tapered off laxatives and has been maintained on linaclotide only. Dyssynergic defecation may be a common finding in Prader-Willi syndrome. In selected cases we recommend anorectal manometry to identify neuromuscular dysfunction and subsequent biofeedback therapy depending on the degree of mental retardation to minimize overuse of laxatives.

  17. Urinary incontinence in persons with Prader-Willi Syndrome

    NARCIS (Netherlands)

    Gontard, A. von; Didden, H.C.M.; Sinnema, M.; Curfs, L.M.G.

    2010-01-01

    OBJECTIVE To assess and identify the frequency and type of urinary incontinence (UI), as well as associated symptoms in persons with Prader-Willi syndrome (PWS). PWS is characterized by mental retardation, short stature, obesity and hypogonadism. The behavioural phenotype includes eating problems,

  18. Trabalho fonoaudiologico em oficina de cozinha em um caso de Prader-Willi Kitchen workshop on the speech-language therapeutic processes of a patient with Prader-Willi syndrome

    Directory of Open Access Journals (Sweden)

    Nathalia Zambotti

    2013-02-01

    Full Text Available TEMA: o objetivo deste estudo é descrever e analisar os efeitos do trabalho fonoaudiológico em Oficina de Cozinha, em processo terapêutico de um paciente portador da síndrome de Prader-Willi. PROCEDIMENTOS: a pesquisa é um estudo de caso de uma criança de 5 anos portadora da Síndrome de Prader-Willi, que apresentava atraso de linguagem e transtornos alimentares. A criança participou durante sete meses do processo terapêutico em Oficina de Cozinha, associado à terapia fonoaudiológica individual. O registro do material clínico foi realizado sistematicamente por escrito, ao longo de cada uma das sessões. RESULTADOS: o caso estudado modificou para melhor seu funcionamento miofuncional oral e de linguagem, como por exemplo: organizando sua função mastigatória e ganhando autonomia da capacidade discursiva. Assumindo a indissociabilidade entre o orgânico e o psíquico, a criança, que apresenta marcas orgânicas advindas da Síndrome, usufruiu de potencialidades da Oficina de Cozinha. CINCLUSÃO: as Oficinas de Cozinha, na condição de dispositivo terapêutico fonoaudiológico, mostrou-se pertinente à articulação biopsíquica no tratamento de pacientes cujas marcas orgânicas determinam limites e especificidades à aquisição e à circulação na linguagem, como são os casos de portadores da síndrome de Prader-Willi.BACKGROUND: describe and analyze the effects of the speech-language work in the Kitchen Workshop on the therapeutic processes of a patient with Prader-Willi syndrome. PROCEDURES: the research is a clinical case study on one child, 5-year old, with Prader-Willi Syndrome, with a delay in speech and feeding problems. The child took part during seven months of the therapeutic process in Kitchen Workshop, associated with individual speech therapy. The clinical material was recorded systematically in writing throughout each one of the sessions. RESULTS: the studied case ameliorated his myo-functional oral functioning and

  19. Trabalho fonoaudiologico em oficina de cozinha em um caso de Prader-Willi Kitchen workshop on the speech-language therapeutic processes of a patient with Prader-Willi syndrome

    Directory of Open Access Journals (Sweden)

    Nathalia Zambotti

    2011-01-01

    Full Text Available TEMA: o objetivo deste estudo é descrever e analisar os efeitos do trabalho fonoaudiológico em Oficina de Cozinha, em processo terapêutico de um paciente portador da síndrome de Prader-Willi. PROCEDIMENTOS: a pesquisa é um estudo de caso de uma criança de 5 anos portadora da Síndrome de Prader-Willi, que apresentava atraso de linguagem e transtornos alimentares. A criança participou durante sete meses do processo terapêutico em Oficina de Cozinha, associado à terapia fonoaudiológica individual. O registro do material clínico foi realizado sistematicamente por escrito, ao longo de cada uma das sessões. RESULTADOS: o caso estudado modificou para melhor seu funcionamento miofuncional oral e de linguagem, como por exemplo: organizando sua função mastigatória e ganhando autonomia da capacidade discursiva. Assumindo a indissociabilidade entre o orgânico e o psíquico, a criança, que apresenta marcas orgânicas advindas da Síndrome, usufruiu de potencialidades da Oficina de Cozinha. CINCLUSÃO: as Oficinas de Cozinha, na condição de dispositivo terapêutico fonoaudiológico, mostrou-se pertinente à articulação biopsíquica no tratamento de pacientes cujas marcas orgânicas determinam limites e especificidades à aquisição e à circulação na linguagem, como são os casos de portadores da síndrome de Prader-Willi.BACKGROUND: describe and analyze the effects of the speech-language work in the Kitchen Workshop on the therapeutic processes of a patient with Prader-Willi syndrome. PROCEDURES: the research is a clinical case study on one child, 5-year old, with Prader-Willi Syndrome, with a delay in speech and feeding problems. The child took part during seven months of the therapeutic process in Kitchen Workshop, associated with individual speech therapy. The clinical material was recorded systematically in writing throughout each one of the sessions. RESULTS: the studied case ameliorated his myo-functional oral functioning and

  20. Analysis of the symmetric configuration of the circle of Willis in a series of autopsied corpses.

    Science.gov (United States)

    Stojanović, Nebojga; Stefanović, Ivica; Kostić, Aleksandar; Radisavejević, Misa; Stojanov, Dragan; Petrović, Sladjana

    2015-04-01

    The forming of the blood vessels network configuration at the base of the brain and interconnecting of blood vessels during the embryogenesis is directly related to the phylogenetic development of the brain and brain structures. A blood vessel configuration at the brain base, in the form of a ring or a hexagon, stands in direct relation to the perfusion needs of certain parts of the brain during its primary differentiation. The aim of this paper was to determine the incidence of certain blood vessel configurations at the base of the brain and understanding their symmetry or asymmetry. Analysis of the blood vessels at the base of the brain was performed on the autopsied subjects. The object of observation was the anterior segment of the circle of Willis consisting of C1- a. carotis interna (ICA), above a. communicaus posterior (PcoA), the segment A1 a. cerebri anterior (ACA) from a. carotis interna bifurcation to the a. communicans anterior (AcoA) and a communicans anterior itself, as well as the posterior segment consisting of PcoA and the segment P1--a. cerebri posterior (PCA) from the a. basilaris bifurcation to the PcoA. For the purpose of grouping the findings, the four basic configuration types of the circle of Willis were identified based on its symmetry or asymmetry. Type-A (symmetric circle of Willis), type-B (asymmetric circle of Willis' due to the unilateral hypoplastic A1-ACA); type-C (symmetric circle of Willis with bilateral symmetric changes on PcoA) and type-D (asymmetric circle of Willis due to the asymmetric changes on PcoA). Autosy was performed on 56 corpses. A total of 41 (73.2%) subjects were recorded with a symmetric configuration of the circle of Willis', of which 27 (48.2%) subjects had type A and 14 (25%) type C. The asymmetric configuration was present in 15 (26.8%) subjects, of whom 9 (16%) had type B and 6 (10.8%) subjects, of whom 9 (16%) had type B and 6 (10.8%) type D. The symmetric Willis group (73.2%) did not have a homogeneous

  1. Analysis of the symmetric configuration of the circle of Willis in a series of autopsied corpses

    Directory of Open Access Journals (Sweden)

    Stojanović Nebojša

    2015-01-01

    Full Text Available Introduction. The forming of the blood vessels network configuration at the base of the brain and interconnecting of blood vessels during the embryogenesis is directly related to the phylogenetic development of the brain and brain structures. A blood vessel configuration at the brain base, in the form of a ring or a hexagon, stands in direct relation to the perfusion needs of certain parts of the brain during its primary differentiation. The aim of this paper was to determine the incidence of certain blood vessel configurations at the base of the brain and understanding their symmetry or asymmetry. Methods. Analysis of the blood vessels at the base of the brain was performed on the autopsied subjects. The object of observation was the anterior segment of the circle of Willis consisting of C1- a. carotis interna (ICA, above a. communicaus posterior (PcoA, the segment A1 a. cerebri anterior (ACA from a. carotis interna bifurcation to the a. communicans anterior (AcoA and a. communicans anterior itself, as well as the posterior segment consisting of PcoA and the segment P1 - a. cerebri posterior (PCA from the a. basilaris bifurcation to the PcoA. For the purpose of grouping the findings, the four basic configuration types of the circle of Willis were identified based on its symmetry or asymmetry. Type-A (symmetric circle of Willis, type-B (asymmetric circle of Willis' due to the unilateral hypoplastic A1-ACA; type-C (symmetric circle of Willis with bilateral symmetric changes on PcoA and type-D (asymmetric circle of Willis due to the asymmetric changes on PcoA. Results. Autopsy was performed on 56 corpses. A total of 41 (73.2% subjects were recorded with a symmetric configuration of the circle of Willis', of which 27 (48.2% subjects had type A and 14 (25% type C. The asymmetric configuration was present in 15 (26.8% subjects, of whom 9 (16% had type B and 6 (10.8% type D. The symmetric Willis group (73.2% did not have a homogeneous finding that

  2. Prader-Willi Syndrome in Two Institutionalized Older Adults.

    Science.gov (United States)

    Goldman, Jeri J.

    1988-01-01

    Two case reports are presented of institutionalized women who were diagnosed as having Prader-Willi syndrome at the ages of 54 and 69. Implications are discussed for management of such persons and for program planning/funding for a much longer life expectancy than earlier realized. (Author/JDD)

  3. Psychiatric disorders and behavioral problems in children with Prader-Willi syndrome and the effects of growth hormone treatment

    NARCIS (Netherlands)

    S.T. Lo (Sinddie)

    2015-01-01

    markdownabstract__Abstract__ This thesis includes studies about developmental, behavioral and psychiatric characteristics in children with Prader-Willi syndrome (PWS). Endocrinologists Prader, Labhart, and Willi were the first describing the combination of neonatal hypotonia, short

  4. Determination of sodium bis(2-ethylhexylsulfosuccinate (AOT surfactant with liquid chromatography: Comparative study of evaporative light scattering detector, ultraviolet detector and conductivity detector

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    Ho Ryul Ryu

    2010-03-01

    Full Text Available This work presents comparison of performance of ultraviolet (UV detector, conductivity detector (CD and evaporative light scattering detector (ELSD in terms of quantitative analysis of AOT (sodium bis(2-ethylhexylsulfosuccinate using liquid chromatography. The employed chromatographic condition, including an acetonitrile/water (45:55, v/v isocratic eluent system, is suitable for the three different detectors, and the figures of merits obtained by building up calibration plots are compared. The sensitivities of the detectors are in the order of ELSD ≈ CD >> UV detector. The linear range for quantification of AOT depends on the type of detector: the lower limits are in the order of UV detector (207 ㎍ mL-1 < CD (310 ㎍ mL-1 << ELSD (930 ㎍ mL-1, while the upper limits are 3720 ㎍ mL-1 for all the detectors (the maximum concentration of injected standard solution. The detection limits are 155 ㎍ mL-1 for ELSD, 78 ㎍ mL-1 for UV detector and 13 ㎍ mL-1 for CD, respectively. The figures of merit for each detector could be a guideline in choosing a detector in quantization of AOT. Furthermore, application of the chromatographic method to two commercial products is demonstrated.

  5. Comparative analysis of autistic traits and behavioral disorders in Prader-Willi syndrome and Asperger disorder.

    Science.gov (United States)

    Song, Dae Kwang; Sawada, Masayuki; Yokota, Shingo; Kuroda, Kenji; Uenishi, Hiroyuki; Kanazawa, Tetsufumi; Ogata, Hiroyuki; Ihara, Hiroshi; Nagai, Toshiro; Shimoda, Kazutaka

    2015-01-01

    Prader-Willi syndrome (PWS) is a neuro-genetic disorder caused by the absence/loss of expression of one or more paternally expressed genes on chromosome 15 (q11-13). In this study, a comparative analysis of intelligence level and autistic traits was conducted between children with PWS (n = 30; 18 males, 12 females; age = 10.6 ± 2.8 years) and those with Asperger disorder (AD; n = 31; 24 males, 7 females; age = 10.5 ± 3.1 years). The children were compared by age group: lower elementary school age (6-8 years), upper elementary school age (9-12 years), and middle school age (13-15 years). As results, the intelligence levels of children with PWS were significantly lower than those with AD across all age groups. Autistic traits, assessed using the Pervasive Developmental Disorders Autism Society Japan Rating Scale (PARS), revealed that among elementary school age children, those with PWS had less prominent autistic traits than those with AD, however, among middle school age children, those with PWS and AD showed similar prominence. An analysis of the PARS subscale scores by age group showed that while the profiles of autistic traits for children with PWS differed from those of children with AD at elementary school age, the profiles showed no significant differences between the groups at middle school age. The findings suggest that autistic traits in PWS become gradually more prominent with increasing of age and that these autistic traits differ in their fundamental nature from those observed in AD. © 2014 Wiley Periodicals, Inc.

  6. Gait Pattern in Two Rare Genetic Conditions Characterized by Muscular Hypotonia: Ehlers-Danlos and Prader-Willi Syndrome

    Science.gov (United States)

    Cimolin, Veronica; Galli, Manuela; Vismara, Luca; Grugni, Graziano; Camerota, Filippo; Celletti, Claudia; Albertini, Giorgio; Rigoldi, Chiara; Capodaglio, Paolo

    2011-01-01

    This study aimed to quantify and compare the gait pattern in Ehlers-Danlos (EDS) and Prader-Willi syndrome (PWS) patients to provide data for developing evidence-based rehabilitation strategies. Twenty EDS and 19 PWS adult patients were evaluated with an optoelectronic system and force platforms for measuring kinematic and kinetic parameters…

  7. Endocrine management of children with Prader–Willi syndrome

    Directory of Open Access Journals (Sweden)

    Medeiros CB

    2013-10-01

    Full Text Available Clarice Borschiver Medeiros,1 Ana Paula Bordallo,1 Flavio Moutinho Souza,2 Paulo Ferrez Collett-Solberg1,31Endocrinology Unit, Departamento de Medicina Interna, Faculdade de Ciências Médicas, Universidade do Estado do Rio de Janeiro (UERJ, Rio de Janeiro, Brazil; 2Pediatric Endocrinology Unit, Departamento de Pediatria, Hospital Federal Cardoso Fontes – Ministério da Saúde do Brasil, Brasília, Brazil; 3Laboratório de Pesquisas Clínicas e Experimentais em Biologia Vascular (BioVasc, Universidade do Estado do Rio de Janeiro (UERJ, Rio de Janeiro, BrazilAbstract: Prader–Willi syndrome is a rare genetic condition afflicting nearly 1/15,000 live births. Clinical features include neonatal hypotonia, poor weight gain in early infancy followed by binge eating from childhood to adulthood, severe obesity, developmental delay, short stature, and hypogonadism of both central and peripheral etiology. Central hypothyroidism and adrenal insufficiency may occur. Sleep disordered breathing, by obstruction of upper airways associated with central hypoventilation, is a common feature. Most of these characteristics are assumed to be the result of a hypothalamic dysfunction. The most important complication and the most difficult to manage is the obesity. This review aims at discussing the most recent strategies to manage the endocrine complications of Prader–Willi syndrome patients, with a special approach on the treatment of obesity, hypogonadism, and short stature. We summarize the indication and effects of recombinant human growth hormone therapy on growth, cognitive development, and body composition, and discuss the effects of recombinant human growth hormone therapy on the resulting sleep disorders.Keywords: Prader–Willi syndrome, obesity, hypogonadism, growth hormone, sleep disorder

  8. SNORD116 deletions cause Prader-Willi syndrome with a mild phenotype and macrocephaly.

    Science.gov (United States)

    Fontana, P; Grasso, M; Acquaviva, F; Gennaro, E; Galli, M L; Falco, M; Scarano, F; Scarano, G; Lonardo, F

    2017-10-01

    Prader-Willi syndrome is a complex condition caused by lack of expression of imprinted genes in the paternally derived region of chromosome 15 (15q11q13). A small number of patients with Prader-Willi phenotype have been discovered to have narrow deletions, not encompassing the whole critical region, but only the SNORD116 cluster, which includes genes codifying for small nucleolar RNAs. This kind of deletion usually is not detected by the classic DNA methylation analysis test. We present the case of a male patient with a mild Prader-Willi phenotype and a small deletion including SNORD116, diagnosed by methylation-sensitive multiplex ligation-dependent probe amplification (MLPA. The patient showed neonatal hypotonia, hyperphagia, obesity, central hypogonadism, hypothyroidism, strabismus. Stature and intellectual development are within the normal range. The presence of macrocephaly, observed in other cases of SNORD116 deletions as well, is uncommon for the classic phenotype of the syndrome. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  9. Birth prevalence of Prader-Willi syndrome in Australia.

    Science.gov (United States)

    Smith, A; Egan, J; Ridley, G; Haan, E; Montgomery, P; Williams, K; Elliott, E

    2003-03-01

    This is the first population based study to estimate the birth prevalence of DNA proven Prader-Willi syndrome. Thirty infants were reported to the Australian Paediatric Surveillance Unit between 1998 and 2000, a prevalence of 4 per 100,000 live births or approximately 1/25,000 live births per annum.

  10. Experience of severe desaturation during anesthetic induction period in an obese adult patient with Prader-Willi syndrome -A case report-.

    Science.gov (United States)

    Choi, Joon Woo; Kim, Eun-Ju; Min, Byung Woo; Ban, Jong Seouk; Lee, Sang Gon; Lee, Ji-Hyang

    2012-02-01

    Prader-Willi syndrome is characterized by infantile hypotonia, childhood-onset obesity, short stature, mental retardation, hyperphagia, hypogonadism. After infantile hypotonia phase, patient is prone to morbid obesity due to hyperphagia. Complications associated with morbid obesity are recognized as the main risk factors for death the lifespan of patients with Prader-Willi syndrome. We experienced desaturation and bronchospasm during arteriovenous fistula surgery in an obese adult with Prader-Willi syndrome.

  11. The itinerary of a non-medal olympic athlete: Willy Seewald (*1900 +1929

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    Janice Zarpellon Mazo

    2017-07-01

    Full Text Available This research investigates the Willy Seewald Olympic sports journey, since the time he started playing sports, through their participation in the Olympic Games in 1924, until the end of his sporting career in the late 1920s. The sources used in this study were interviews, newspapers, magazines, official documents and Seewald family personnel collection. The information extracted and interpreted by document analysis, revealed that Willy Seewald, in addition to practicing a wide range of sports, achieved high performance in Olympic sport Javelin Throw and has shown by his conduct that the Olympic values were incorporated in its habitus.

  12. Severe neonatal-onset panniculitis in a female infant with Prader-Willi syndrome.

    Science.gov (United States)

    Sakthivel, Muthukumar; Hughes, Stephen M; Riley, Phil; Arkwright, Peter D; Mukherjee, Anindya; Ramsden, Simon; Urquhart, Jill; Crow, Yanick J

    2011-12-01

    The panniculitides are a group of heterogeneous inflammatory diseases involving the subcutaneous fat, the pathogenesis of which is poorly understood. Here, we report on a female infant with Prader-Willi syndrome who developed a systemic inflammatory disorder in the neonatal period demonstrating recurrent panniculitis as a prominent feature. This is the second report of an association between Prader-Willi syndrome and panniculitis. Such an association might be explained by the unmasking of a recessive allele as a consequence of hemizygosity, in the case of a 15q11 deletion, or homozygosity, in the case of maternal isodisomy. Copyright © 2011 Wiley Periodicals, Inc.

  13. Salivary flow rate and oral findings in Prader-Willi syndrome: a case-control study.

    Science.gov (United States)

    Saeves, Ronnaug; Nordgarden, Hilde; Storhaug, Kari; Sandvik, Leiv; Espelid, Ivar

    2012-01-01

    BACKGROUND. Prader-Willi syndrome (PWS) is a rare complex multisystemic genetic disorder. AIM. The objective of this study was to provide a systematic assessment of whole saliva secretion and oral manifestations associated with PWS. DESIGN. Fifty individuals (5-40 years) with PWS and an age- and sex-matched control group were included. Whole saliva was collected. All participants underwent an anamnestic interview. Radiological and dental clinical examinations were carried out to identify hypodontia, dental caries, enamel defects and gingival inflammation. RESULTS. Mean whole salivary flow rate was 0.12 ± 0.11 mL/min in the study group compared with 0.32 ± 0.20 mL/min in the control group (P 19 years was significantly lower in PWS (P = 0.04) compared with the controls. There was no significant difference in the prevalence of dental caries in the primary dentition or in the frequency of enamel defects in the permanent dentition between the two groups. Median Gingival Index was significantly higher in the Prader-Willi group compared with the controls (P = 0.02). CONCLUSIONS. Low salivary flow is a consistent finding in PWS. Nevertheless, despite dry mouth and dietary challenges, dental caries is not increased in Norwegian individuals with PWS. © 2011 The Authors. International Journal of Paediatric Dentistry © 2011 BSPD, IAPD and Blackwell Publishing Ltd.

  14. Polysomnography test and sleep disordered breathing in Prader-Willi syndrome

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    Andreea- Iulia Dobrescu1,

    2016-12-01

    Full Text Available INTRODUCTION Prader Willi syndrome (PWS is a rare condition and represents the most frequent cause of syndromic obesity. Sleep apnea is a life-threatening affection and is documented as the main cause of sudden death in PWS. OBJECTIVES AND BACKGROUND The aim of our study was to evaluate sleep disorders in PWS patients. MATERIALS AND METHODS We used a portable monitor that recorded time in bed (TIB, the air flow in the upper airways, oxygen saturation, heart rate and snoring. The included patients had a positive clinical and molecular diagnosis of PWS. RESULTS The mean of TIB was 439.3±117.19 minutes. We recorded obstructive, central and mixed apnea, hypopnea and short wakes caused by respiratory events that were variable number and duration, in all patients. cardiovascular morbidity and mortality and improved life quality. Moreover, small doses of these drugs proved to be effective even in patients where hemodialysis alone was enough to control blood pressure. CONCLUSIONS Sleep disorders are present in most PWS patients, not only obese ones according to their anatomical particularities. These events prevent the use of growth hormone therapy, the only available treatment that decreases the adipose mass and increase both prognosis and life quality in PWS patients. Graphical abstract: Polysomnography Test in a PWS patient. REFERENCES 1. Vandeleur M, Davey MJ, Nixon GM. Are sleep studies helpful in children with Prader-Willi syndrome prior to commencement of growth hormone therapy? J Paediatr Child Health. 2013;49:238–41. 2. Giordano L, Toma S, Palonta F, Teggi R, Zucconi M, Candia SD, et al. Obstructive sleep apnea in Prader-Willi syndrome: risks and advantages of adenotonsillectomy. Pediatr Med Chir. 2015;37(2. 3. Pavone M, Caldarelli V, Khirani S, Colella M, Ramirez A, Aubertin G, et al. Sleep disordered breathing in patients with Prader-Willi syndrome: A multicenter study. Pediatr Pulmonol. 2015;50:1354–9

  15. Adult Prader-Willi Syndrome: An Update on Management

    OpenAIRE

    Ho-Ming, Luk

    2016-01-01

    With the advancement of medical care, the survival of most patients with syndromal genetic disease is greatly improved. In this case report, we have reported an adult Prader-Willi syndrome patient who is being diagnosed at the age of 33. The clinical features and their associated complications during adulthood have been reviewed.

  16. The Dual Role of Cerebral Autoregulation and Collateral Flow in the Circle of Willis After Major Vessel Occlusion.

    Science.gov (United States)

    Kennedy McConnell, Flora; Payne, Stephen

    2017-08-01

    Ischaemic stroke is a leading cause of death and disability. Autoregulation and collateral blood flow through the circle of Willis both play a role in preventing tissue infarction. To investigate the interaction of these mechanisms a one-dimensional steady-state model of the cerebral arterial network was created. Structural variants of the circle of Willis that present particular risk of stroke were recreated by using a network model coupled with: 1) a steady-state physiological model of cerebral autoregulation; and 2) one wherein the cerebral vascular bed was modeled as a passive resistance. Simulations were performed in various conditions of internal carotid and vertebral artery occlusion. Collateral flow alone is unable to ensure adequate blood flow ([Formula: see text] normal flow) to the cerebral arteries in several common variants during internal carotid artery occlusion. However, compared to a passive model, cerebral autoregulation is better able to exploit available collateral flow and maintain flows within [Formula: see text] of baseline. This is true for nearly all configurations. Hence, autoregulation is a crucial facilitator of collateral flow through the circle of Willis. Impairment of this response during ischemia will severely impact cerebral blood flows and tissue survival, and hence, autoregulation should be monitored in this situation.

  17. Brief Report: Repetitive Behaviour Profiles in Williams Syndrome: Cross Syndrome Comparisons with Prader-Willi and Down Syndromes

    Science.gov (United States)

    Royston, R.; Oliver, C.; Moss, J.; Adams, D.; Berg, K.; Burbidge, C.; Howlin, P.; Nelson, L.; Stinton, C.; Waite, J.

    2018-01-01

    This study describes the profile of repetitive behaviour in individuals with Williams syndrome, utilising cross-syndrome comparisons with people with Prader-Willi and Down syndromes. The Repetitive Behaviour Questionnaire was administered to caregivers of adults with Williams (n = 96), Prader-Willi (n = 103) and Down (n = 78) syndromes. There were…

  18. The Need for Control/Comparison Studies in Establishing Diagnostic Indicators: Prader-Willi Syndrome as a Case in Point.

    Science.gov (United States)

    Taylor, Ronald L.; Caldwell, Mary Lou

    1990-01-01

    The psychometric characteristics of 12 adults with Prader-Willi syndrome (PWS) and a group without PWS but with other similar traits were compared. Results found cognitive, behavioral and educational traits often associated with PWS to be present in both groups, illustrating the importance of control/comparison groups in research establishing…

  19. Adult Prader-Willi Syndrome: An Update on Management

    Directory of Open Access Journals (Sweden)

    Luk Ho-Ming

    2016-01-01

    Full Text Available With the advancement of medical care, the survival of most patients with syndromal genetic disease is greatly improved. In this case report, we have reported an adult Prader-Willi syndrome patient who is being diagnosed at the age of 33. The clinical features and their associated complications during adulthood have been reviewed.

  20. Life Satisfaction Among Mothers of Individuals with Prader-Willi Syndrome.

    Science.gov (United States)

    Shivers, Carolyn M; Leonczyk, Caroline L; Dykens, Elisabeth M

    2016-06-01

    Mothers of individuals with Prader-Willi syndrome (PWS) often experience numerous stressors, even when compared to mothers of children with other intellectual and developmental disabilities. Despite this, these mothers show great variability in self-reported life satisfaction. Using data from a longitudinal study of individuals with PWS and their families, the present study analyzed factors related to maternal life satisfaction, both cross-sectionally and over time. Results show that both child factors (e.g., behavior problems, hyperphagia) and maternal factors (e.g., stress, coping style) were significantly related to maternal life satisfaction. However, none of the tested variables predicted change in life satisfaction over time. Research and practice implications are discussed.

  1. Circle of Willis variation in a complex stroke presentation: a case report

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    Young Carolyn A

    2006-03-01

    Full Text Available Abstract Background The impact of circle of Willis anatomical variation upon the presentation of stroke is probably underrecognised. Case presentation A 63-year-old right-handed woman developed a left hemiparesis and right leg weakness sequentially following a road traffic accident (RTA. Despite initial concern about the possibility of cervical spinal cord injury, the final diagnosis was bilateral artery-to-artery embolic cerebral infarction with dominant right internal carotid artery. Conclusion The case illustrates the complex presentation of stroke as a pseudo-cervical cord lesion and the impact of circle of Willis anatomical variation upon the expression of large vessel cerebrovascular disease.

  2. Physical health problems in adults with Prader-Willi syndrome

    NARCIS (Netherlands)

    Sinnema, M.; Maaskant, M.A.; Schrojenstein Lantman-de Valk, H.M.J. van; Nieuwpoort, I.C. van; Drent, M.L.; Curfs, L.M.G.; Schrander-Stumpel, C.T.R.M.

    2011-01-01

    Prader-Willi syndrome (PWS) is a genetic disorder which is characterized by severe hypotonia and feeding problems in early infancy. In later childhood and adolescence, this is followed by hyperphagia and extreme obesity if the diet is not strictly controlled. Data on physical health problems in

  3. Visual-Motor Integration in Children with Prader-Willi Syndrome

    Science.gov (United States)

    Lo, S. T.; Collin, P. J. L.; Hokken-Koelega, A. C. S.

    2015-01-01

    Background: Prader-Willi syndrome (PWS) is characterised by hypotonia, hypogonadism, short stature, obesity, behavioural problems, intellectual disability, and delay in language, social and motor development. There is very limited knowledge about visual-motor integration in children with PWS. Method: Seventy-three children with PWS aged 7-17 years…

  4. Mosaic maternal uniparental disomy of chromosome 15 in Prader-Willi syndrome: utility of genome-wide SNP array.

    Science.gov (United States)

    Izumi, Kosuke; Santani, Avni B; Deardorff, Matthew A; Feret, Holly A; Tischler, Tanya; Thiel, Brian D; Mulchandani, Surabhi; Stolle, Catherine A; Spinner, Nancy B; Zackai, Elaine H; Conlin, Laura K

    2013-01-01

    Prader-Willi syndrome is caused by the loss of paternal gene expression on 15q11.2-q13.2, and one of the mechanisms resulting in Prader-Willi syndrome phenotype is maternal uniparental disomy of chromosome 15. Various mechanisms including trisomy rescue, monosomy rescue, and post fertilization errors can lead to uniparental disomy, and its mechanism can be inferred from the pattern of uniparental hetero and isodisomy. Detection of a mosaic cell line provides a unique opportunity to understand the mechanism of uniparental disomy; however, mosaic uniparental disomy is a rare finding in patients with Prader-Willi syndrome. We report on two infants with Prader-Willi syndrome caused by mosaic maternal uniparental disomy 15. Patient 1 has mosaic uniparental isodisomy of the entire chromosome 15, and Patient 2 has mosaic uniparental mixed iso/heterodisomy 15. Genome-wide single-nucleotide polymorphism array was able to demonstrate the presence of chromosomally normal cell line in the Patient 1 and trisomic cell line in Patient 2, and provide the evidence that post-fertilization error and trisomy rescue as a mechanism of uniparental disomy in each case, respectively. Given its ability of detecting small percent mosaicism as well as its capability of identifying the loss of heterozygosity of chromosomal regions, genome-wide single-nucleotide polymorphism array should be utilized as an adjunct to the standard methylation analysis in the evaluation of Prader-Willi syndrome. Copyright © 2012 Wiley Periodicals, Inc.

  5. Small mosaic deletion encompassing the snoRNAs and SNURF-SNRPN results in an atypical Prader-Willi syndrome phenotype.

    Science.gov (United States)

    Anderlid, Britt-Marie; Lundin, Johanna; Malmgren, Helena; Lehtihet, Mikael; Nordgren, Ann

    2014-02-01

    Genetic analyses were performed in a male patient with suspected Prader-Willi syndrome who presented with hypogonadism, excessive eating, central obesity, small hands and feet and cognition within the low normal range. However, he had no neonatal hypotonia or feeding problems during infancy. Chromosome analysis showed a normal male karyotype. Further analysis with array-CGH identified a mosaic 847 kb deletion in 15q11-q13, including SNURF-SNRPN, the snoRNA gene clusters SNORD116 (HBII-85), SNORD115, (HBII-52), SNORD109 A and B (HBII-438A and B), SNORD64 (HBII-13), and NPAP1 (C15ORF2). MLPA confirmed the deletion and the results were compatible with a paternal origin. Metaphase-FISH verified the mosaicism with the deletion present in 58% of leukocytes analyzed. Three smaller deletions in this region have previously been reported in patients with Prader-Willi syndrome phenotype. All three deletions included SNORD116, but only two encompassed parts of SNURF-SNRPN, implicating SNORD116 as the major contributor to the Prader-Willi phenotype. Our case adds further information about genotype-phenotype correlation and supports the hypothesis that SNORD116 plays a major role in the pathogenesis of Prader-Willi syndrome. Furthermore, it examplifies diagnostic difficulties in atypical cases and illustrates the need for additional testing methods when Prader-Willi syndrome is suspected. © 2013 Wiley Periodicals, Inc.

  6. The Effects of Muscle Hypotonia and Weakness on Balance: A Study on Prader-Willi and Ehlers-Danlos Syndrome Patients

    Science.gov (United States)

    Galli, Manuela; Cimolin, Veronica; Vismara, Luca; Grugni, Graziano; Camerota, Filippo; Celletti, Claudia; Albertini, Giorgio; Rigoldi, Chiara; Capodaglio, Paolo

    2011-01-01

    Prader-Willi syndrome (PWS) and Ehlers-Danlos syndrome (EDS) are two different genetical disorders both characterized, among other features, by muscular hypotonia. Postural control seems to be impaired in both conditions. The aim of the present study was to quantitatively compare postural control in adult PWS and EDS using stabilometric platform…

  7. Elevated plasma oxytocin levels in children with Prader-Willi syndrome compared with healthy unrelated siblings.

    Science.gov (United States)

    Johnson, Lisa; Manzardo, Ann M; Miller, Jennifer L; Driscoll, Daniel J; Butler, Merlin G

    2016-03-01

    Prader-Willi syndrome (PWS) is a rare genetic disorder associated with distinct abnormal behaviors including hyperphagia, profound social deficits, and obsessive-compulsive tendencies. PWS males showed reduced oxytocin receptor (OTR) gene expression and density in the hypothalamic paraventricular nucleus that may play a role in PWS psychopathology. Oxytocin is an anorexigenic neuropeptide similar to vasopressin that is associated with social cognition and obsessive-compulsive behavior. To evaluate oxytocin biology in PWS, we examined overnight fasting plasma oxytocin levels in 23 children with PWS (mean ± SD age: 8.2 ± 2.0 year) having genetic confirmation and 18 age matched healthy unrelated siblings without PWS (mean ± SD age: 8.2 ± 2.3 year) and a similar gender ratio under the same clinical assessments, specimen processing and laboratory conditions. Multiplex immune assays were carried out using the Milliplex Human Neuropeptide Magnetic panel and the Luminex system. Natural log-transformed oxytocin levels were analyzed using general linear model adjusting for diagnosis, gender, age and body mass index (BMI). Oxytocin plasma levels were significantly elevated in children with PWS (168 ± 121 pg/ml) compared with unrelated and unaffected siblings without the diagnosis of PWS (64.8 ± 83.8 pg/ml, F = 8.8, P model fit R(2) = 0.33 (P < 0.01). The symptoms of hyperphagia, anxiety and repetitive behaviors classically seen in PWS may be related to the disruption of oxytocin responsivity or feedback in the hypothalamic paraventricular nucleus possibly influencing vasopressin signaling. Further study is needed to characterize oxytocin function in PWS. © 2015 Wiley Periodicals, Inc.

  8. Klinefelter's syndrome and Prader-Willi syndrome: A rare combination

    NARCIS (Netherlands)

    Verhoeven, W.M.A.; Vries, B.B. van; Duffels, S.J.H.; Egger, J.I.M.; Noordam, C.; Tuinier, S.

    2007-01-01

    In this paper a review is presented of the rare combination of Klinefelter's syndrome and Prader-Willi syndrome (PWS) and a second case of this combination with a uniparental disomy (UPD) etiology of PWS is described. Patients outlined in all other 8 reports and the present case have a PWS

  9. Klinefelter's syndrome and Prader-Willi syndrome: a rare combination.

    NARCIS (Netherlands)

    Verhoeven, W.M.A.; Vries, B.B. van; Duffels, S.J.H.; Egger, J.I.M.; Noordam, C.; Tuinier, S.

    2007-01-01

    In this paper a review is presented of the rare combination of Klinefelter's syndrome and Prader-Willi syndrome (PWS) and a second case of this combination with a uniparental disomy (UPD) etiology of PWS is described. Patients outlined in all other 8 reports and the present case have a PWS

  10. An anatomical study of normal variations of circle of Willis in 132 fetus, newborn and adult

    Directory of Open Access Journals (Sweden)

    Bateni F

    2009-09-01

    Full Text Available "n Normal 0 false false false EN-US X-NONE AR-SA MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:Arial; mso-bidi-theme-font:minor-bidi;} Background: Several studies have investigated the variations in the anatomy of each segment of circle of Willis whereas a few have addressed the variations of this arterial circle as a whole. In this study the entire circle of Willis and its variations were studied in a cohort of Iranian people and compared with previous reports."n"nMethods: Anatomical variations of the circle of Willis in 132 brains of Iranian cadavers (102 male adults and 30 fetuses and infants were studied. The dissection process was digitally filmed for further studies. Using computer software the external diameters of the vessels were measured and the circle variations were classified. The variations of the circle as a whole and segmental variations were compared with previous studies. "n"nResults: Uni-and bilateral hypoplasia of posterior communicating arteries (PcoAs constituted the most common variation in our study which was similar to previous works. Aplasia of the anterior cerebral artery (A1 and the posterior cerebral artery (P1 were not observed. In 3.3% of fetuses and infants and 3% of adult instances both right and left posterior communicating arteries were absent. There was one case of anterior communicating artery (AcoA aplasia in

  11. Capability of abdominal 320-detector row CT for small vasculature assessment compared with that of 64-detector row CT

    Energy Technology Data Exchange (ETDEWEB)

    Kitajima, Kazuhiro, E-mail: kitajima@med.kobe-u.ac.jp [Department of Radiology, Kobe University Graduate School of Medicine, 7-5-2, Kusunoki-cho, Chuo-ku, Kobe, Hyogo 650-0017 (Japan); Maeda, Tetsuo; Ohno, Yoshiharu [Department of Radiology, Kobe University Graduate School of Medicine, 7-5-2, Kusunoki-cho, Chuo-ku, Kobe, Hyogo 650-0017 (Japan); Division of Radiology, Kobe University Hospital, Kobe (Japan); Yoshikawa, Takeshi [Department of Radiology, Kobe University Graduate School of Medicine, 7-5-2, Kusunoki-cho, Chuo-ku, Kobe, Hyogo 650-0017 (Japan); Konishi, Minoru [Division of Radiology, Kobe University Hospital, Kobe (Japan); Kanda, Tomonori; Onishi, Yumiko; Matsumoto, Keiko; Koyama, Hisanobu; Takenaka, Daisuke; Sugimura, Kazuro [Department of Radiology, Kobe University Graduate School of Medicine, 7-5-2, Kusunoki-cho, Chuo-ku, Kobe, Hyogo 650-0017 (Japan)

    2011-11-15

    Objective: To compare the capability of 320-detector row CT (area-detector CT: ADCT) with step-and-shoot scan protocol for small abdominal vasculature assessment with that of 64-detector row CT with helical scan protocol. Materials and methods: Total of 60 patients underwent contrast-enhanced abdominal CT for preoperative assessment. Of all, 30 suspected to have lung cancer underwent ADCT using step-and-shoot scan protocol. The other 30 suspected to have renal cell carcinoma underwent 64-MDCT using helical scan protocol. Two experienced radiologists independently assessed inferior epigastric, hepatic subsegmental (in the segment 8), mesenteric marginal (Griffith point) and inferior phrenic arteries by using 5-point visual scoring systems. Kappa analysis was used for evaluation of interobserver agreement. To compare the visualization capability of the two systems, the Mann-Whitney U-test was used to compare the scores for each of the arteries. Results: Overall interobserver agreements for both systems were almost perfect ({kappa} > 0.80). Visualization scores for inferior epigastric and mesenteric arteries were significantly higher for ADCT than for 64-detector row CT (p < 0.05). No significant difference was found for hepatic subsegmental and inferior phrenic arteries. Conclusion: Small abdominal vasculature assessment by ADCT with step-and-shoot scan protocol is potentially equal to or better than that by 64-detector row CT with helical scan protocol.

  12. Capability of abdominal 320-detector row CT for small vasculature assessment compared with that of 64-detector row CT

    International Nuclear Information System (INIS)

    Kitajima, Kazuhiro; Maeda, Tetsuo; Ohno, Yoshiharu; Yoshikawa, Takeshi; Konishi, Minoru; Kanda, Tomonori; Onishi, Yumiko; Matsumoto, Keiko; Koyama, Hisanobu; Takenaka, Daisuke; Sugimura, Kazuro

    2011-01-01

    Objective: To compare the capability of 320-detector row CT (area-detector CT: ADCT) with step-and-shoot scan protocol for small abdominal vasculature assessment with that of 64-detector row CT with helical scan protocol. Materials and methods: Total of 60 patients underwent contrast-enhanced abdominal CT for preoperative assessment. Of all, 30 suspected to have lung cancer underwent ADCT using step-and-shoot scan protocol. The other 30 suspected to have renal cell carcinoma underwent 64-MDCT using helical scan protocol. Two experienced radiologists independently assessed inferior epigastric, hepatic subsegmental (in the segment 8), mesenteric marginal (Griffith point) and inferior phrenic arteries by using 5-point visual scoring systems. Kappa analysis was used for evaluation of interobserver agreement. To compare the visualization capability of the two systems, the Mann-Whitney U-test was used to compare the scores for each of the arteries. Results: Overall interobserver agreements for both systems were almost perfect (κ > 0.80). Visualization scores for inferior epigastric and mesenteric arteries were significantly higher for ADCT than for 64-detector row CT (p < 0.05). No significant difference was found for hepatic subsegmental and inferior phrenic arteries. Conclusion: Small abdominal vasculature assessment by ADCT with step-and-shoot scan protocol is potentially equal to or better than that by 64-detector row CT with helical scan protocol.

  13. Treatment of traumatic internal carotid artery pseudoaneurysms with willis covered stents: a midterm follow-up result

    International Nuclear Information System (INIS)

    Wang Wu; Li Minghua; Li Yongdong; Gu Binxian; Fang Chun; Tan Huaqiao; Wang Ju; Zhang Peilei

    2010-01-01

    Objective: To evaluate the efficacy and mid-term follow-up results of endovascular treatment with Willis covered stent for traumatic pseudoaneurysms located in the internal carotid artery (ICA). Methods: ICA angiography was performed in 38 patients with traumatic brain and neck injury. Of the 38 patients, 13 delayed traumatic pseudoaneurysms were found. All the pseudoaneurysms were treated with Willis covered stents. Follow-up angiography was performed at 1, 3, 6 and 12 months after the procedure, and the results were categorized as complete or incomplete occlusion. Clinical manifestations were graded as full recovery, improvement, unchanged and aggravation. Results: Willis covered stent placement was technically successful in all traumatic pseudoaneurysms. No procedure-related complications occurred. The initial angiographic results showed a complete occlusion in 9 patients, and an incomplete occlusion in 4. The angiographic follow-up within 3-12 months exhibited a complete occlusion in 12 patients and the parent arteries remained patency in all patients. The clinical follow-up observation demonstrated that full recovery was obtained in 11 patients, clinical improvement in one, and unchanged condition in one. No morbidity or mortality occurred. Conclusion: Willis covered stent implantation is a feasible and practical treatment for traumatic pseudoaneurysms located in the ICA. This technique can well preserve the parent artery with excellent therapeutic results. (authors)

  14. Prader-Willi syndrome in South African patients clinical and ...

    African Journals Online (AJOL)

    Prader-Willi syndrome in. South African patients clinical and molecular diagnosis. A L Christianson, 0 L Viljoen, W S Winship,. M de la Rey, E J van Rensburg. Study objective. ... This probe detects a parent-of-origin-specific methylation imprint at locus ... These studies were undertaken in the Molecular Genetic. Laboratory of ...

  15. Clinical implications of gait analysis in the rehabilitation of adult patients with "Prader-Willi" Syndrome: a cross-sectional comparative study ("Prader-Willi" Syndrome vs matched obese patients and healthy subjects

    Directory of Open Access Journals (Sweden)

    Baccalaro Gabriele

    2007-05-01

    Full Text Available Abstract Background Being severely overweight is a distinctive clinical feature of Prader-Willi Syndrome (PWS. PWS is a complex multisystem disorder, representing the most common form of genetic obesity. The aim of this study was the analysis of the gait pattern of adult subjects with PWS by using three-Dimensional Gait Analysis. The results were compared with those obtained in a group of obese patients and in a group of healthy subjects. Methods Cross-sectional, comparative study: 19 patients with PWS (11 males and 8 females, age: 18–40 years, BMI: 29.3–50.3 kg/m2; 14 obese matched patients (5 males and 9 females, age: 18–40 years, BMI: 34.3–45.2 kg/m2; 20 healthy subjects (10 males and 10 females, age: 21–41 years, BMI: 19.3–25.4 kg/m2. Kinematic and kinetic parameters during walking were assessed by an optoelectronic system and two force platforms. Results PWS adult patients walked slower, had a shorter stride length, a lower cadence and a longer stance phase compared with both matched obese, and healthy subjects. Obese matched patients showed spatio-temporal parameters significantly different from healthy subjects. Furthermore, Range Of Motion (ROM at knee and ankle, and plantaflexor activity of PWS patients were significantly different between obese and healthy subjects. Obese subjects revealed kinematic and kinetic data similar to healthy subjects. Conclusion PWS subjects had a gait pattern significantly different from obese patients. Despite that, both groups had a similar BMI. We suggest that PWS gait abnormalities may be related to abnormalities in the development of motor skills in childhood, due to precocious obesity. A tailored rehabilitation program in early childhood of PWS patients could prevent gait pattern changes.

  16. Prader-willi syndrome: A case report and a Chinese literature review.

    Science.gov (United States)

    Zhu, Junzhen; Cao, Qinying; Zhang, Ning; Zhao, Lijuan

    2013-11-01

    Prader-Willi syndrome (PWS) is a genetic disorder, resulting from lack of gene expression on the paternally inherited chromosome 15. It is important to determine diagnostic methods for PWS for early treatment. In this study, we report a newborn with Prader-willi syndrome. We further summarized the genetic testing results in the Chinese literature and the relevance of high resolution chromosome and genome-wide copy number variation analysis. There is a heterozygosis deletion of a 5 Mb region in the paternal chromosome 15q11.3-q13.3 by genome-wide copy number variation analysis. However, there is no abnormality in high resolution chromosome karyotype analysis. In conclusion, genome-wide copy number variation analysis is an effective and specific diagnosis method, which will provide scientific evidence for the clinical diagnosis and early treatment of PWS.

  17. Pituitary-Adrenal Axis in Prader Willi Syndrome

    Directory of Open Access Journals (Sweden)

    Olivia S. Edgar

    2016-01-01

    Full Text Available Purpose: Prader Willi syndrome (PWS is a rare genetic condition that has concurrent endocrinological insufficiencies. The presence of growth hormone deficiency has been well documented, but adrenal insufficiency (AI is not widely reported. A review was conducted to investigate its prevalence and relevance in PWS in both adults and children. Methodology: A literature review was performed with the search terms “Prader-Willi syndrome” and “adrenal insufficiency”. Results: The review found studies disagree on the prevalence and method of investigation of AI in PWS. Case studies demonstrate that patients with PWS are at risk of premature death, often secondary to respiratory infections. The possibility that this may be the result of the inability to mount an effective cortisol response has been studied, with some evidence confirming AI in PWS patients. Most reports agreed AI is present in PWS, however, Farholt et al. showed no HPA axis dysfunction in adults, suggesting that perhaps it is rare in adults, and children should be the focus of further studies. Conclusion: AI is present in some patients with PWS. Further research is required to ensure optimal treatment can be implemented and to prevent premature deaths related to adrenal insufficiency. Clinicians should have a low threshold for testing the adrenal axis and considering treatment for adrenal insufficiency in PWS patients.

  18. Prader-Willie Syndrome in the Practice of Pediatrician. Modern Approaches to the Diagnosis and Treatment

    Directory of Open Access Journals (Sweden)

    T.M. Khimenko

    2015-05-01

    Full Text Available Objective. To familiarize the doctors with diagnostic criteria and modern comprehensive approach to the treatment of children with Prader-Willie syndrome. The problems of treatment with growth hormone, social integration of patients were stressed, a clinical case from practice is presented. The analysis of the scientific literature of leading foreign and domestic authors has been carried out. The article presents the current approaches to early diagnosis based on large and small diagnostic criteria already at the first months of life, indications for molecular-genetic testing by fish-method to detect microdeletions of chromosome 15. A case of Prader-Willi syndrome demonstrates the typical clinical manifestations, the need for a multidisciplinary approach and continuous monitoring of patients. Conclusions. Prader-Willi syndrome has characteristic features that can be detected in most patients during the first six months of life, which will made it possible to carry out timely correction of metabolic and hormonal disorders and to improve quality of life. To clarify the diagnosis, genetic testing, which today became available in most regions of Ukraine, is successfully performed. The question of supporting hormone therapy that enables to adjust significantly the phenotype of patients with Prader-Willi syndrome, providing adequate physical development, is still open. Long-term use of recombinant growth hormone can prevent a number of complications characteristic of the syndrome, and to improve the quality of life for patients in the future.

  19. Prader-Willi syndrome, excessive daytime sleepiness, and narcoleptic symptoms: a case report.

    Science.gov (United States)

    Weselake, Sara V; Foulds, Jessica L; Couch, Robert; Witmans, Manisha B; Rubin, Daniela; Haqq, Andrea M

    2014-04-17

    Sleep abnormalities, including narcolepsy and cataplexy, are a common feature of Prader-Willi syndrome. Long-term treatment with the central nervous system stimulant modafinil has not been reported. In this case report we present a longitudinal perspective of sleep abnormalities in a nine-year-old Caucasian girl with Prader-Willi syndrome from age two to age nine, and detail the response to treatment with the central nervous system stimulant modafinil. Our patient presented at two years of age with hypersomnia and narcoleptic episodes with cataplectic features. Initial polysomnograph testing revealed adequate sleep efficiency, but increased sleep fragmentation especially during rapid eye movement sleep. The narcoleptic episodes continued and a repeat polysomnograph at age five years confirmed features consistent with narcolepsy. Further sleep studies at six years, including a multiple sleep latency test, demonstrated signs of excessive daytime sleepiness. Treatment with modafinil was initiated at age seven years six months due to persistent hypersomnia and narcoleptic symptoms. Two polysomnograph studies were performed following treatment with modafinil, at age eight years six months and nine years three months. These studies showed excellent sleep efficiency and improvement of rapid eye movement sleep parameters, supporting the beneficial effects of long-term modafinil therapy. Long-term modafinil therapy may ameliorate the sleep disturbances of Prader-Willi syndrome and should be the focus of future clinical trials.

  20. Altered functional brain networks in Prader–Willi syndrome

    OpenAIRE

    Zhang, Yi; Zhao, Heng; Qiu, Siyou; Tian, Jie; Wen, Xiaotong; Miller, Jennifer L.; von Deneen, Karen M.; Zhou, Zhenyu; Gold, Mark S.; Liu, Yijun

    2013-01-01

    Prader–Willi syndrome (PWS) is a genetic imprinting disorder characterized mainly by hyperphagia and early childhood obesity. Previous functional neuroimaging studies used visual stimuli to examine abnormal activities in the eating-related neural circuitry of patients with PWS. It was found that patients with PWS exhibited both excessive hunger and hyperphagia consistently, even in situations without any food stimulation. In the present study, we employed resting-state functional MRI techniqu...

  1. Phonologic Abilities of a Preschool Child with Prader-Willi Syndrome.

    Science.gov (United States)

    Dyson, Alice T.; Lombardino, Linda J.

    1989-01-01

    A case study follows the development of phonologic abilities in a child with Prader-Willi syndrome, during her enrollment in language and phonologic remediation from age 2:7 to 6:1. Changes in her phonetic inventory, in the set of phonemes used correctly, and in phonologic processes are described. (Author/JDD)

  2. Childhood subdural hemorrhage, macrocephaly, and coagulopathy associated with Prader-Willi syndrome: case report and review of the literature.

    Science.gov (United States)

    Carr, Robert B; Khanna, Paritosh C; Saneto, Russell P

    2012-07-01

    A 16-month-old girl with a history of Prader-Willi syndrome and progressive macrocephaly manifested large, bilateral, subdural hemorrhages of differing ages on magnetic resonance imaging. Subsequent evaluation revealed a deficiency of von Willebrand factor, but after repeated evaluations, no conclusive evidence of nonaccidental trauma became apparent. Subdural hemorrhages of varying ages are frequently associated with nonaccidental trauma during early childhood. However, several uncommon conditions may present as subdural hemorrhages and thus mimic nonaccidental trauma. Our patient demonstrates a combination of Prader-Willi syndrome, von Willebrand factor deficiency, and enlargement of the extra-axial spaces. All of these in isolation were associated with subdural hemorrhages. We review the scant literature on subdural hemorrhages in Prader-Willi syndrome and other conditions that mimic nonaccidental trauma. Copyright © 2012 Elsevier Inc. All rights reserved.

  3. Cerebral cross-perfusion and the Circle of Willis: does physiology trump anatomy?

    Directory of Open Access Journals (Sweden)

    Musicki K

    2017-07-01

    Full Text Available Korana Musicki,1 Katherine Victoria Hurst,1,2 Zoltán Molnár,3 Elizabeth Hardy,4 Ashok Handa,1,2 1Department of Vascular Surgery, John Radcliffe Hospital, 2Nuffield Department of Surgical Sciences, 3Department of Physiology, Anatomy and Genetics, University of Oxford, 4Vascular Studies Unit, John Radcliffe Hospital, Oxford, UK Introduction: Cerebral cross-perfusion is essential for ipsilateral brain viability during unilateral insult. Aortic arch and great vessel procedures depend on its function for safe practice, unless adjuncts like shunts are used. This paper assesses the contribution of cerebrovascular anatomy against physiology in determining requisite hemispheric perfusion during carotid endarterectomy (CEA.Materials and methods: A review of shunting requirements for CEAs under locoregional anesthesia (LA at the John Radcliffe Hospital during 1999–2013 was performed. A PubMed search for “Circle of Willis” was screened for all original articles defining cerebrovascular anatomy by postmortem or angiography.Results: Over 14 years, 1137 CEAs were performed under cervical plexus block; during this period, the departmental standard of practice evolved from exclusively general anesthesia to predominantly LA. CEAs performed under LA during the early phase (1999–2003 had a shunt rate of 15.1%, compared to 20% as predicted by stump pressures alone. However, shunting decreased as higher perioperative systolic pressures were routinely practiced; shunt rates were 8.0% during the intermediate (2004–2007 and 6.4% during the later (2008–2013 phase. By comparison, 25 articles characterizing 6414 brains report an intact circle of Willis in 33–35% of people, with a complete hemi-circle anteriorly (77% seen more commonly than posteriorly (42%, and 11–16% deficient in both hemi-circles with no cross-flow.Conclusion: Cerebral cross-perfusion is fundamental for safe CEA. Anatomy of the circle of Willis alone does not itself determine adequacy

  4. Tenth annual scientific conference of the Prader-Willi Syndrome Association (USA), July 19, 1995, Seattle, Washington

    Energy Technology Data Exchange (ETDEWEB)

    Holm, V.A.; Hudgins, L. [Univ. of Washington School of Medicine, Seattle, WA (United States); Cassidy, S.B. [Univ. of Washington School of Medicine, and Children`s Hospital and Medical Center, Seattle, WA (United States)]|[Univ. Hospitals of Cleveland, OH (United States)

    1996-09-06

    Each year for the last 10 years, scientists conducting research on Prader-Willi syndrome have come together to exchange information during a scientific conference held in conjunction with the annual Prader-Willi Syndrome Association (USA) meeting. Presentations based on submitted abstracts encompass such varied fields as genetics, endocrinology, pediatrics, nutrition, psychology, psychiatry, and education. This year`s scientific conference was held in Seattle, Washington, on July 19, 1995, in conjunction with the 14th PWSA (USA) meeting held July 20-23. Seventeen reports were presented at the scientific meeting, the abstracts of which follow.

  5. Microsurgery for Aneurysms on the Circle of Willis | de Klerk | South ...

    African Journals Online (AJOL)

    A description of a microsurgical approach for aneurysms on the anterior part of the circle of Willis is given. Certain practical points are stressed. The operative results obtained in 37 consecutive aneurysms operated on in 30 patients are discussed. S. Afr. Med. J., 48, 825 (1974).

  6. [Multiorgan failure associated with hyperthermia in an infant with Prader-Willi syndrome. case report].

    Science.gov (United States)

    Donoso, Alejandro; Arriagada, Daniela; Campbell, Stephanie; Cruces, Pablo

    2013-10-01

    Heat stroke is a medical emergency characterized primarily by an elevated core temperature associated with a systemic inflammatory response, which causes multiple organ dysfunction in which encephalopathy predominates. If it is not early treated has high mortality. The Prader-Willi syndrome is a multisystem genetic disorder secondary to an abnormality in long arm chromosome 15 (15q11-q13), characterized by neonatal central hypotonia, developmental delay, hypogonadism, hyperphagia and obesity. These patients are susceptible to developing thermoregulatory problems. We report the case of a 5-month-old infant, in whom a diagnosis of Prader-Willi syndrome was established in the course of a febrile episode without known focus, who developed multiorganic failure and rhabdomyolysis secondary to hyperthermia.

  7. Behavioural and Emotional Disturbances in People with Prader-Willi Syndrome

    Science.gov (United States)

    Steinhausen, H.-C.; Eiholzer, U.; Hauffa, B. P.; Malin, Z.

    2004-01-01

    The study of the behaviour profile in subjects with Prader-Willi Syndrome (PWS). A total of fifty-eight 3- to 29-year-old subjects with PWS were studied using a standardized parent report of behavioural and emotional disturbances. There was an increase of behavioural and emotional disturbances for the adolescent and young adult age range, whereas…

  8. Students with Prader-Willi Syndrome: Case Law under the IDEA

    Science.gov (United States)

    Zirkel, Perry A.

    2017-01-01

    Prader-Willi Syndrome (PWS) is one of the low-incidence physical disabilities that the literature has not addressed in relation to the Individuals with Disabilities Education Act and its case law applications. To help fill the gap, this relatively brief article provides (a) an introduction of PWS from legal sources; (b) an overview of the IDEA,…

  9. Physiological adaptation after a 12-week physical activity program for patients with Prader-Willi syndrome: two case reports.

    Science.gov (United States)

    Amaro, Alexandre Slowetzky; Teixeira, Maria Cristina Triguero Veloz; de Mesquita, Maria Luiza Guedes; Rodrigues, Graciele Massoli; Rubin, Daniela Andrea; Carreiro, Luiz Renato Rodrigues

    2016-06-23

    Physical activity programs are a powerful tool against several diseases including obesity and their comorbidities. Prader-Willi syndrome is the most common genetic disease associated with obesity, and brings with it behavioral and emotional problems that need complex management. Research into the effect of physical activity programs on Prader-Willi syndrome is limited and it is frequently argued that if a physical activity program is too complex, the participants are more likely to drop out. Therefore, in this study, we assessed the physiological adaptation effect of a physical activity program with increasing complexity and load, in a boy and a girl with Prader-Willi syndrome by assessing changes in lipid profile, body composition, and physical fitness parameters. Case 1 was an 11-year-old girl, mixed race (brown), with an intelligence quotient of 68, 52.0 % body fat, and a body mass index of 45.3 kg/m(2). The Prader-Willi syndrome diagnosis was made when she was 5-years old and was found to be due to an imprinting genomic defect. Case 2 was a 14-year-old boy, mixed race (brown), with an intelligence quotient of 74, 48.8 % body fat, and a body mass index of 37.3 kg/m(2). The diagnosis was made when he was 10-years old and was found to be caused by gene deletion. Both participants presented physical characteristics and behavior problems typical of Prader-Willi syndrome. Case 2 presented high blood pressure, high cholesterol and sleep apnea and had to use continuous positive airway pressure to sleep. Both participants were assessed for 12 weeks (three times a week) using a physical activity program designed to improve strength and muscle hypertrophy. The work load was progressively adjusted as necessary and new exercises were added to the program. Prior to the program, the participants' parents received instructions about managing problem behavior and advice about nutrition. After physical activity program several health markers assessed by biological tests and

  10. Prader-Willi Syndrome, Management of Impulsivity, and Hyperphagia in an Adolescent.

    Science.gov (United States)

    Puri, M Rehan; Sahl, Robert; Ogden, Shawwna; Malik, Salma

    2016-05-01

    The aim of this article is to review related literature on management of hyperphagia and impulsive behaviors in Prader-Willi syndrome (PWS) that includes either naltrexone or bupropion. In this article we also discuss a case of a 13-year-old female with PWS struggling with some behavioral and psychiatric symptoms.

  11. [Prader-Willi syndrome case with proliferative diabetic retinopathy in both eyes treated by early vitrectomy under local anesthesia].

    Science.gov (United States)

    Hori, Hideyuki; Sato, Yukihiro; Nakashima, Motohiro; Nakajima, Motohiro

    2012-02-01

    Although patients with Prader-Willi syndrome have a high rate of diabetes, to date, there have been only 4 reported cases (6 eyes) undergoing vitrectomy for proliferative diabetic retinopathy. Herein, we report a case of Prader-Willi syndrome with proliferative diabetic retinopathy that was treated by early vitrectomy OU under local anesthesia. A 30-year-old man was diagnosed as having Prader-Willi syndrome at the age of 2 years and diabetes at age 17. He was referred to our hospital as diabetic retinopathy had been detected in his first ophthalmological examination at age 29. Visual acuity was 0.6 bilaterally. Proliferative retinopathy, with cataract and macular edema, was identified in both eyes. Panretinal photocoagulation was performed on both eyes. However, proliferative membranes developed bilaterally, and vitreous hemorrhage occurred OS. Visual acuity decreased to 0.3 OU. The patient was hospitalized at our internal medicine department for blood glucose control. Subsequently, with an anesthesiologist on standby, a hypnotic sedative was injected intramuscularly, achieving retro-bulbar anesthesia. Combined cataract and vitreous surgery was performed on the left eye. One week later, a similar operation was performed on the right eye. The patient was discharged four days later. In the two years since these operation, visual acuity has been maintained at 0.8 OU. Patients with Prader-Willi syndrome should be examined for early detection and treatment of diabetic retinopathy.

  12. Magnetic resonance angiography (MRA) of the circle of Willis: a prospective comparison with conventional angiography in 54 subjects

    International Nuclear Information System (INIS)

    Patrux, B.; Laissy, J.P.; Jouini, S.; Kawiecki, W.; Coty, P.; Thiebot, J.

    1994-01-01

    We prospectively correlated the findings of magnetic resonance angiography (MRA) with those of transfemoral four-vessel angiography in 54 patients to investigate the direction of flow within the circle of Willis. Our primary goal was to assess the direction of flow using the size of the vessel and signal intensity, without saturation techniques. Analysis of the circle of Willis, especially the communicating arteries, was performed double-blind by two groups of two radiologists. Three types of arteries were identified: high flow or cross-cerebral circulation, patent and nonvisualised arteries. Cerebral angiography was the standard for comparison between the two methods. MRA did not reveal any arteries invisible on angiography, thus providing a specificity of 100%. The sensitivity of MRA was 89.2% for the anterior and 81.3% for the posterior communicating arteries, and 100% for the anterior, middle and posterior cerebral arteries. MRA was shown to be a useful technique for the assessment of patency of the circle of Willis. (orig.)

  13. Magnetic resonance angiography (MRA) of the circle of Willis: a prospective comparison with conventional angiography in 54 subjects

    Energy Technology Data Exchange (ETDEWEB)

    Patrux, B. (Neuroradiology, CHU Charles Nicolle, Rouen (France)); Laissy, J.P. (Neuroradiology, CHU Charles Nicolle, Rouen (France) Dept. of Radiology, CHU Bichat, Paris (France)); Jouini, S. (Neuroradiology, CHU Charles Nicolle, Rouen (France)); Kawiecki, W. (Siemens Medical Systems, Saint-Denis (France)); Coty, P. (Neuroradiology, CHU Charles Nicolle, Rouen (France)); Thiebot, J. (Neuroradiology, CHU Charles Nicolle, Rouen (France))

    1994-04-01

    We prospectively correlated the findings of magnetic resonance angiography (MRA) with those of transfemoral four-vessel angiography in 54 patients to investigate the direction of flow within the circle of Willis. Our primary goal was to assess the direction of flow using the size of the vessel and signal intensity, without saturation techniques. Analysis of the circle of Willis, especially the communicating arteries, was performed double-blind by two groups of two radiologists. Three types of arteries were identified: high flow or cross-cerebral circulation, patent and nonvisualised arteries. Cerebral angiography was the standard for comparison between the two methods. MRA did not reveal any arteries invisible on angiography, thus providing a specificity of 100%. The sensitivity of MRA was 89.2% for the anterior and 81.3% for the posterior communicating arteries, and 100% for the anterior, middle and posterior cerebral arteries. MRA was shown to be a useful technique for the assessment of patency of the circle of Willis. (orig.)

  14. Synchrony of oculocutaneous albinism, the Prader-Willi syndrome, and a normal karyotype.

    Science.gov (United States)

    Wallis, C E; Beighton, P H

    1989-01-01

    A Chinese girl with oculocutaneous albinism has the Prader-Willi syndrome and a normal karyotype. This association emphasises the importance of further molecular study of the 15(q12) region of the genome in the search for the locus of an albinism gene. Images PMID:2732995

  15. Severe obstructive sleep disorders in Prader-Willi syndrome patients in southern Italy.

    Science.gov (United States)

    Canora, Angelo; Franzese, Adriana; Mozzillo, Enza; Fattorusso, Valentina; Bocchino, Marialuisa; Sanduzzi, Alessandro

    2018-01-09

    Sleep-related disordered breathing (SDB) is very common in paediatric patients affected by Prader-Willi Syndrome (PWS). However, data addressing SBD patterns and their management are lacking. The aim of the present study was to analyse SDB features in 14 PWS patients (age range, 8 months-17 years). Polygraphic registration (PG) during a 12-h nocturnal sleep was performed in all patients. Obstructive and central apnoea indices and oxygen saturation (SpO 2 ) were recorded along with demographic and clinical data. Obstructive sleep apnoea (OSA) was diagnosed in 13/14 patients (92.9%); the mean obstructive apnoea-hypopnea index (OAHI) was 7.6 ± 4.2 events/h with a mean central apnoea index (CAI) of 0.7 ± 1.04 events/h. Time spent with SpO 2 Prader-Willi syndrome. What is New: • Severe obstructive sleep apnoea is the most frequent sleep-related disorder in our case series.

  16. Willis PM 10-2.5 Precision Results, pdf has summary table and SEM images

    Data.gov (United States)

    U.S. Environmental Protection Agency — Precision data from the SEM and SEM images from the samples. This dataset is associated with the following publication: Peters, T., E. Sawvel, R. Willis, R. West,...

  17. A Transcriptomic Signature of the Hypothalamic Response to Fasting and BDNF Deficiency in Prader-Willi Syndrome

    Directory of Open Access Journals (Sweden)

    Elena G. Bochukova

    2018-03-01

    Full Text Available Summary: Transcriptional analysis of brain tissue from people with molecularly defined causes of obesity may highlight disease mechanisms and therapeutic targets. We performed RNA sequencing of hypothalamus from individuals with Prader-Willi syndrome (PWS, a genetic obesity syndrome characterized by severe hyperphagia. We found that upregulated genes overlap with the transcriptome of mouse Agrp neurons that signal hunger, while downregulated genes overlap with the expression profile of Pomc neurons activated by feeding. Downregulated genes are expressed mainly in neuronal cells and contribute to neurogenesis, neurotransmitter release, and synaptic plasticity, while upregulated, predominantly microglial genes are involved in inflammatory responses. This transcriptional signature may be mediated by reduced brain-derived neurotrophic factor expression. Additionally, we implicate disruption of alternative splicing as a potential molecular mechanism underlying neuronal dysfunction in PWS. Transcriptomic analysis of the human hypothalamus may identify neural mechanisms involved in energy homeostasis and potential therapeutic targets for weight loss. : Prader-Willi syndrome (PWS is a genetic obesity syndrome. Bochukova et al. report gene expression changes in the hypothalamus of people with PWS that support neurodegeneration and neuroinflammation as key processes involved in this condition. Keywords: hypothalamus, Prader-Willi syndrome, BDNF, Agrp, obesity, SNORD116

  18. Escoliosis y síndrome de Prader-Willi: a propósito de 5 casos intervenidos quirúrgicamente Escoliose e síndrome de Prader-Willi: análise de cinco casos tratados cirurgicamente Scoliosis and Prader-Willi syndrome: review of five cases treated surgically

    Directory of Open Access Journals (Sweden)

    Jose Grass Pedrals

    2012-06-01

    Full Text Available OBJETIVO: Analizar los resultados y las complicaciones del tratamiento quirúrgico de la escoliosis, en pacientes portadores del Síndrome de Prader-Willi, para verificar si se justifica este tipo de tratamiento. MÉTODOS: Análisis retrospectivo de las fichas clínicas y radiografías de los cinco pacientes portadores del Síndrome de Prader-Willi que consultaron en el Departamento de Escoliosis entre los años 2005 y 2010, y fueron operados. RESULTADOS: La edad de la consulta inicial fue en promedio 3,6 años; el promedio de escoliosis fue 61º, el que aumentó a 65º al momento de la cirugía. El promedio de operaciones realizadas fue 2,8 por paciente, lográndose una corrección promedio de 35%. Los motivos de las reintervenciones fueron pérdida de corrección en 4 casos (28,5%, aflojamiento de ganchos en 2 (14,3% y xifosis referente a la instrumentación en uno (7,1% No hubo complicaciones graves. CONCLUSIONES: Aún cuando la literatura muestra autores poco proclives a indicar cirugía en este tipo de pacientes, por la elevada tasa de complicaciones graves, la ausencia de ellas en nuestro medio hace mantener válidos los mismos criterios quirúrgicos que en escoliosis idiopática.OBJETIVO: Analisar os resultados e as complicações do tratamento cirúrgico da escoliose em pacientes com síndrome de Prader-Willi para verificar se esse tipo de tratamento é justificado. MÉTODOS: Análise retrospectiva dos prontuários clínicos e das radiografias dos cinco pacientes portadores de síndrome de Prader-Willi tratados cirurgicamente no Departamento de Escoliose entre 2005 e 2010. RESULTADOS: A média de idade dos pacientes na consulta inicial foi 3,6 anos. A média de escoliose foi 61º, a qual tinha aumentado para 65º na ocasião da cirurgia. A média de cirurgias realizadas foi 2,8 por paciente, atingindo-se correção média de 35%. Os motivos das re-intervenções foram perda de correção em quatro casos (28,5%, afrouxamento dos ganchos

  19. Intraoperative Adrenal Insufficiency in a Patient with Prader-Willi Syndrome

    OpenAIRE

    Barbara, David W.; Hannon, James D.; Hartman, William R.

    2012-01-01

    Prader-Willi syndrome (PW) is a rare genetic disorder with multi-organ system involvement. These patients present many perioperative challenges including sleep-related breathing disorders, morbid obesity, thick salivary secretions, mental retardation, and difficult intravenous access. PW has been suggested to be associated with central adrenal insufficiency. We report a novel case of persistent severe hypotension from previously undiagnosed and asymptomatic adrenal insufficiency in a pediatri...

  20. Testicular failure in boys with Prader-Willi syndrome: Longitudinal studies of reproductive hormones

    NARCIS (Netherlands)

    E.P.C. Siemensma (Elbrich); R.F.A. De Lind Van Wijngaarden (Roderick F.); B.J. Otten (Barto); F.H. de Jong (Frank); A.C.S. Hokken-Koelega (Anita)

    2012-01-01

    textabstractContext: The pathophysiology of hypogonadism in boys with Prader-Willi Syndrome( PWS) remains uncertain. Several reports described hypogonadotropic hypogonadism, some reported primary gonadal failure, and others a combination of both. Objectives: The aim of the study was to evaluate

  1. Testicular failure in boys with Prader-Willi syndrome: longitudinal studies of reproductive hormones.

    NARCIS (Netherlands)

    Siemensma, E.P.C.; Lind van Wijngaarden, R.F. de; Otten, B.J.; Jong, F.H. de; Hokken-Koelega, A.C.S.

    2012-01-01

    CONTEXT: The pathophysiology of hypogonadism in boys with Prader-Willi Syndrome (PWS) remains uncertain. Several reports described hypogonadotropic hypogonadism, some reported primary gonadal failure, and others a combination of both. OBJECTIVES: The aim of the study was to evaluate gonadal function

  2. The Relationship between Specific Cognitive Impairment and Behaviour in Prader-Willi Syndrome

    Science.gov (United States)

    Woodcock, K. A.; Oliver, C.; Humphreys, G. W.

    2011-01-01

    Background: Individuals with Prader-Willi syndrome (PWS) have been shown to demonstrate a particular cognitive deficit in attention switching and high levels of preference for routine and temper outbursts. This study assesses whether a specific pathway between a cognitive deficit and behaviour via environmental interaction can exist in individuals…

  3. Siim Nestor soovitab : Goldie. Kevin Saunderson. Nicole Willis. King Britt / Siim Nestor

    Index Scriptorium Estoniae

    Nestor, Siim, 1974-

    2005-01-01

    Popmuusikaüritustest: briti muusik Goldie esineb jungle-muusikaga Tallinnas 21. apr. klubis Privé, DJ Kevin Saunderson 22. apr. klubis Privé, laulja Nicole Willis 27. apr. BonBon Jazz Lounge'il klubis BonBon, Philadelphia muusik King Britt ja Eesti ansambel Broken Time Orchestra esitlevad oma heliplaate

  4. Sex and Genes, Part 1: Sexuality and down, Prader-Willi, and Williams Syndromes

    Science.gov (United States)

    Watson, Shelley Lynn; Richards, Deborah A.; Miodrag, Nancy; Fedoroff, J. Paul

    2012-01-01

    Specific genetic syndromes affect individuals' sexual development, experiences, and fertility. Individuals with specific syndromes can also display inappropriate sexual behavior resulting from vulnerabilities presented by their genetic makeup. Using clinical case studies, we discuss the specific impact that Down, Prader-Willi, and Williams…

  5. Management of Speech and Language Impairment in a Case of Prader-Willi Syndrome.

    Science.gov (United States)

    Edmonston, Nellie K.

    1982-01-01

    The case report describes the speech and language charactersitics of a five-year-old girl with Prader-Willi syndrome, a congential disorder (characterized by mental retardation and specific physical characteristics), and the language therapy procedures used over a 10-month period. (Author/SW)

  6. Growth hormone usage in Prader-Willi syndrome

    OpenAIRE

    Damiani, Durval

    2008-01-01

    A síndrome de Prader-Willi (PWS), com prevalência de 60:1.000.000, é o resultado da perda de parte do cromossomo 15 paterno, em razão da deleção em 56% dos casos, dissomia uniparental materna em 24% dos casos, ou por causa da metilação, fenômeno epigenético, em 18% dos casos. O quadro clínico inicia-se com profunda hipotonia que, especialmente no primeiro ano de vida, torna difícil a alimentação da criança. Conforme melhora a hipotonia, nos primeiros dois anos, por volta do quarto ano de vida...

  7. Physical health problems in adults with Prader-Willi syndrome.

    Science.gov (United States)

    Sinnema, Margje; Maaskant, Marian A; van Schrojenstein Lantman-de Valk, Henny M J; van Nieuwpoort, I Caroline; Drent, Madeleine L; Curfs, Leopold M G; Schrander-Stumpel, Constance T R M

    2011-09-01

    Prader-Willi syndrome (PWS) is a genetic disorder which is characterized by severe hypotonia and feeding problems in early infancy. In later childhood and adolescence, this is followed by hyperphagia and extreme obesity if the diet is not strictly controlled. Data on physical health problems in adults with PWS are scarce. We report on the prevalence of physical health problems in a Dutch cohort of adults with PWS in relation to age, BMI, and genetic subtype. Participants (n = 102) were retrieved via the Dutch Prader-Willi Parent Association and through physicians specializing in persons with intellectual disabilities (ID). Details regarding physical health problem spanning the participants' lifespan were collected from caretakers through semi-structured interviews. Cardiovascular problems included diabetes mellitus, hypertension, and cerebrovascular accidents. Respiratory infections were frequent in adulthood. In males, cryptorchidism was almost universal, for which 28/48 males had a history of surgery, mostly orchidopexy. None of the women had a regular menstrual cycle. Sixteen individuals had a diagnosis of osteoporosis. Spinal deformation, hip dysplasia, and foot abnormalities were common. Skinpicking, leg edema, and erysipelas were frequent dermatological problems. The findings in our group support the notion that the prevalence of physical health problems is underestimated. This underscores the importance of developing monitoring programs which would help to recognize physical health problems at an early stage. Copyright © 2011 Wiley-Liss, Inc.

  8. Blount disease in a case of Prader-Willi syndrome: why is it not as prevalent as in obesity without Prader-Willi syndrome?

    Science.gov (United States)

    Dulka, Susan; Choudhary, Arabinda Kumar; Methratta, Sosamma; Fortuna, Kristine

    2013-05-01

    Prader-Willi syndrome (PWS) is a genetic disorder causing multisystem abnormalities with obesity. Obesity is a well established cause of Blount disease. A 7-year-old girl with PWS presented with genu varum of the left knee with deformity of the proximal medial tibial condyle, which was consistent with Blount disease. A lateral physeal stapling and subsequent osteotomy for the left proximal tibia and fibula were performed with improved anatomical alignment. Blount disease has not been reported in the literature in association with PWS despite excessive obesity.

  9. Ravintola konseptia etsimässä : Eksynyt Willi Hirvi

    OpenAIRE

    Mäntynen, Kaisu

    2014-01-01

    Opinnäytetyön tarkoituksena oli selvittää, millaisia palveluita Hotelli Jämsä Oy:n ravintolan Willi Hirven tulisi tarjota saadakseen toimintansa kannattavaksi. Ravintolan konsepti hakee suuntaansa, ja yritys halusi toiminnan suunnittelun avuksi tietoa palveluiden käyttäjiltä, sekä heiltä jotka eivät niitä käytä. Tutkimuksen kohteena olivat työnsä puolesta hotellissa majoittuvat asiakkaat ja paikalliset asukkaat, joita haluttaisiin palvella paremmin. Tutkimus oli otteeltaan kvalitatiivinen....

  10. Recognition of Emotion in Facial Expression by People with Prader-Willi Syndrome

    Science.gov (United States)

    Whittington, J.; Holland, T.

    2011-01-01

    Background: People with Prader-Willi syndrome (PWS) may have mild intellectual impairments but less is known about their social cognition. Most parents/carers report that people with PWS do not have normal peer relationships, although some have older or younger friends. Two specific aspects of social cognition are being able to recognise other…

  11. Treatment of Covert Food Stealing in an Individual with Prader-Willi Syndrome.

    Science.gov (United States)

    Maglieri, Kristen, A.; DeLeon, Iser G.; Rodriguez-Catter, Vanessa; Sevin, Bart M.

    2000-01-01

    A study found verbal reprimands, delivered contingent upon eating prohibited foods, were sufficient to decease the food stealing of a girl (age 14) with Prader-Willi syndrome. Warning stimuli were then successfully used to help her discriminate between permitted/prohibited foods during sessions in which food stealing was not directly observed.…

  12. Microdeletion 15q26.2qter and Microduplication 18q23 in a Patient with Prader-Willi-Like Syndrome: Clinical Findings.

    Science.gov (United States)

    Dello Russo, Patrizia; Demori, Eliana; Sechi, Annalisa; Passon, Nadia; Romagno, Daniela; Gnan, Chiara; Zoratti, Raffaele; Damante, Giuseppe

    2016-01-01

    The small interstitial deletion in the long arm of chromosome 15 causing Prader-Willi/Angelman syndrome is well known, whereas cases that report terminal deletions in 15q in association with the Prader-Willi-like phenotype are very rare. By using GTG-banding analysis, metaphase FISH, MLPA analysis, and genome-wide array CGH, we detected an unbalanced translocation involving a microdeletion of the distal part of 15q and a microduplication of the distal part of 18q. The unbalanced translocation was found in a boy that was referred with clinical suspicion of Prader-Willi syndrome. In the 15q-deleted region, 23 genes have been identified, and 13 of them are included in the OMIM database. Among these, the deleted IGFR1, MEF2A, CHSY1, and TM2D3 genes could contribute to the patient's phenotype. Seven genes are included in the duplicated chromosome segment 18q, but only one (CTDP1) is present in the OMIM database. We suggest that the deleted chromosome segment 15q26.2qter may be responsible for the phenotype of our case and may also be a candidate locus of Prader-Willi-like syndrome. © 2016 S. Karger AG, Basel.

  13. The number of hypothalamic hypocretin (orexin) neurons is not affected in Prader-Willi syndrome.

    NARCIS (Netherlands)

    Fronczek, R.; Lammers, G.J.; Balesar, R.; Unm, U.A.hopa; Swaab, D.F.

    2005-01-01

    CONTEXT: Narcoleptic patients with cataplexy have a general loss of hypocretin (orexin) in the lateral hypothalamus, possibly due to an autoimmune-mediated degeneration of the hypocretin neurons. In addition to excessive daytime sleepiness, Prader-Willi syndrome (PWS) patients may show

  14. The number of hypothalamic hypocretin (orexin) neurons is not affected in Prader-Willi syndrome

    NARCIS (Netherlands)

    Fronczek, Rolf; Lammers, Gert Jan; Balesar, Rawien; Unmehopa, Unga A.; Swaab, Dick F.

    2005-01-01

    Narcoleptic patients with cataplexy have a general loss of hypocretin (orexin) in the lateral hypothalamus, possibly due to an autoimmune-mediated degeneration of the hypocretin neurons. In addition to excessive daytime sleepiness, Prader-Willi syndrome (PWS) patients may show narcolepsy-like

  15. Willis Eugene Lamb (1913 - 2008) - Passion for precision

    International Nuclear Information System (INIS)

    Pain, J.C.

    2013-01-01

    In 1947, Willis Eugene Lamb with Robert Retherford measured a gap between the 2 fine structure levels 2s(1/2) and 2p(1/2) of the hydrogen atom while the Dirac equations gave them the same energy. This discovery called 'Lamb shift' was a driving factor for the development of quantum electrodynamics after the second world war. Lamb has also contributed to various fields of quantum physics, he studied the ejection of electrons by metastable atoms and also the Bose-Einstein condensation. In 1939, he predicted nuclear transitions that led to the discovery of the Moessbauer effect 22 years later

  16. "Hungry Eyes": Visual Processing of Food Images in Adults with Prader-Willi Syndrome

    Science.gov (United States)

    Key, A. P. F.; Dykens, E. M.

    2008-01-01

    Background: Prader-Willi syndrome (PWS) is a genetic disorder associated with intellectual disabilities, compulsivity, hyperphagia and increased risks of life-threatening obesity. Food preferences in people with PWS are well documented, but research has yet to focus on other properties of food in PWS, including composition and suitability for…

  17. Severe tooth wear in Prader-Willi syndrome. A case–control study

    Directory of Open Access Journals (Sweden)

    Saeves Ronnaug

    2012-05-01

    Full Text Available Abstract Background Prader-Willi syndrome (PWS is a rare complex multsystemic genetic disorder characterized by severe neonatal hypotonia, endocrine disturbances, hyperphagia and obesity, mild mental retardation, learning disabilities, facial dysmorphology and oral abnormalities. The purpose of the present study was to explore the prevalence of tooth wear and possible risk factors in individuals with Prader-Willi syndrome. Methods Forty-nine individuals (6-40 years with PWS and an age- and sex-matched control group were included. Tooth wear was evaluated from dental casts and intraoral photographs and rated by four examiners using the Visual Erosion Dental Examination (VEDE scoring system and the individual tooth wear index IA. In accordance with the VEDE scoring system, tooth wear was also evaluated clinically. Whole saliva was collected. Results Mean VEDE score was 1.70 ± 1.44 in the PWS group and 0.46 ± 0.36 in the control group (p A was 7.50 (2.60-30.70 in the PWS group and 2.60 (0.90-4.70 among controls (p A; r = 0.82, p A; r = 0.43, p = 0.002. Tooth grinding was also associated with tooth wear in the PWS group, as indicated by the mean VEDE 2.67 ± 1.62 in grinders and 1.14 ± 0.97 in non-grinders (p = 0.001 and median IA values 25.70 (5.48-68.55 in grinders and 5.70 (1.60-9.10 in non-grinders (p = 0.003. Multivariate linear regression analysis was performed with tooth wear as the dependent variable and PWS (yes/no, age, tooth grinding and saliva secretion as independent variables. PWS (yes/no, age and tooth grinding retained a significant association with tooth wear, VEDE (p A (p  Conclusions Our study provides evidence that tooth wear, in terms of both erosion and attrition, is a severe problem in Prader-Willi syndrome. There is therefore considerable need for prosthodontic rehabilitation in young adults with PWS.

  18. Sharing the Gift of Jazz: An Interview with Willie L. Hill Jr.

    Science.gov (United States)

    Howe, Brad

    2011-01-01

    This article presents an interview with Willie L. Hill Jr., founder and director of the Society for Jazz Education. Currently a professor of music education at the University of Massachusetts-Amherst and the director of the UMass Fine Arts Center, Hill has served as director of education for the Thelonious Monk Institute of Jazz. He is a past…

  19. Modeling the Circle of Willis Using Electrical Analogy Method under both Normal and Pathological Circumstances

    Science.gov (United States)

    Abdi, Mohsen; Karimi, Alireza; Navidbakhsh, Mahdi; Rahmati, Mohammadali; Hassani, Kamran; Razmkon, Ali

    2013-01-01

    Background and objective: The circle of Willis (COW) supports adequate blood supply to the brain. The cardiovascular system, in the current study, is modeled using an equivalent electronic system focusing on the COW. Methods: In our previous study we used 42 compartments to model whole cardiovascular system. In the current study, nevertheless, we extended our model by using 63 compartments to model whole CS. Each cardiovascular artery is modeled using electrical elements, including resistor, capacitor, and inductor. The MATLAB Simulink software is used to obtain the left and right ventricles pressure as well as pressure distribution at efferent arteries of the circle of Willis. Firstly, the normal operation of the system is shown and then the stenosis of cerebral arteries is induced in the circuit and, consequently, the effects are studied. Results: In the normal condition, the difference between pressure distribution of right and left efferent arteries (left and right ACA–A2, left and right MCA, left and right PCA–P2) is calculated to indicate the effect of anatomical difference between left and right sides of supplying arteries of the COW. In stenosis cases, the effect of internal carotid artery occlusion on efferent arteries pressure is investigated. The modeling results are verified by comparing to the clinical observation reported in the literature. Conclusion: We believe the presented model is a useful tool for representing the normal operation of the cardiovascular system and study of the pathologies. PMID:25505747

  20. Brookhaven Lab physicist William Willis wins the 2003 W.K.H. Panofsky prize

    CERN Multimedia

    2003-01-01

    William Willis, a senior physicist Brookhaven National Laboratory, has won the American Physical Society's 2003 W.K.H. Panofsky Prize in Experimental Particle Physics. He received the prize, which consists of $5,000 and a certificate citing his contributions to physics, at the APS meeting in Philadelphia on April 6 (1 page).

  1. Cognitive and Adaptive Advantages of Growth Hormone Treatment in Children with Prader-Willi Syndrome

    Science.gov (United States)

    Dykens, Elisabeth M.; Roof, Elizabeth; Hunt-Hawkins, Hailee

    2017-01-01

    Background: People with Prader-Willi syndrome (PWS) typically have mild to moderate intellectual deficits, compulsivity, hyperphagia, obesity, and growth hormone deficiencies. Growth hormone treatment (GHT) in PWS has well-established salutatory effects on linear growth and body composition, yet cognitive benefits of GHT, seen in other patient…

  2. Altered functional resting-state hypothalamic connectivity and abnormal pituitary morphology in children with Prader-Willi syndrome

    NARCIS (Netherlands)

    A. Lukoshe (Akvile); Van Dijk, S.E. (Suzanne E.); G.E. van den Bosch (Gerbrich); A. van der Lugt (Aad); T.J.H. White (Tonya); A.C.S. Hokken-Koelega (Anita)

    2017-01-01

    textabstractBackground: Prader-Willi syndrome (PWS) is a complex neurodevelopmental disorder, characterized by endocrine problems and hyperphagia, indicating hypothalamic-pituitary dysfunction. However, few studies have explored the underlying neurobiology of the hypothalamus and its functional

  3. A 2D finite element implementation of the Fleck–Willis strain-gradient flow theory

    DEFF Research Database (Denmark)

    Nielsen, Kim Lau; Niordson, Christian Frithiof

    2013-01-01

    The lay-out of a numerical solution procedure for the strain gradient flow (rate-independent) theory by Fleck and Willis [A mathematical basis for strain-gradient theory – Part II: Tensorial plastic multiplier, 57:1045–1057; 2009, JMPS] has been an open issue, and its finite element implementation...

  4. High unacylated ghrelin levels support the concept of anorexia in infants with Prader-Willi syndrome

    NARCIS (Netherlands)

    V. Beauloye (Véronique); G. Diène; R.J. Kuppens (Renske); Zech, F. (Francis); Winandy, C. (Coralie); C. Molinas (Catherine); S. Faye; Kieffer, I. (Isabelle); Beckers, D. (Dominique); R. Nergårdh (Ricard); B.P. Hauffa (Berthold); Derycke, C. (Christine); P.J.D. Delhanty (Patric); A.C.S. Hokken-Koelega (Anita); M. Tauber (Maïthé)

    2016-01-01

    textabstractBackground: Prader-Willi syndrome (PWS) is a rare genetic neurodevelopmental disorder with different nutritional phases from suckling deficit with failure to thrive to early onset of obesity. Hyperghrelinemia has been described in PWS long before the development of obesity. Ghrelin is

  5. Psychomotor development in infants with Prader-Willi syndrome and associations with sleep-related breathing disorders.

    NARCIS (Netherlands)

    Festen, D.A.M.; Wevers, M.; Weerd, A.W. de; Bossche, R.A. van den; Duivenvoorden, H.J.; Otten, B.J.; Wit, J.M.; Hokken-Koelega, A.C.S.

    2007-01-01

    Prader-Willi syndrome (PWS) is a neurogenetic disorder with hypotonia, psychomotor delay, obesity, short stature, and sleep-related breathing disorders. The aim of this study was to evaluate the association between psychomotor development and sleep-related breathing disorders in PWS infants. Bayley

  6. A Preliminary Analysis of the Phenomenology of Skin-Picking in Prader-Willi Syndrome

    Science.gov (United States)

    Morgan, Jessica R.; Storch, Eric A.; Woods, Douglas W.; Bodzin, Danielle; Lewin, Adam B.; Murphy, Tanya K.

    2010-01-01

    To examine the nature and psychosocial correlates of skin-picking behavior in youth with Prader-Willi Syndrome (PWS). Parents of 67 youth (aged 5-19 years) with PWS were recruited to complete an internet-based survey that included measures of: skin-picking behaviors, the automatic and/or focused nature of skin-picking, severity of skin-picking…

  7. The Transition between the Phenotypes of Prader-Willi Syndrome during Infancy and Early Childhood

    Science.gov (United States)

    Butler, Jill V.; Whittington, Joyce E.; Holland, Anthony J.; McAllister, Catherine J.; Goldstone, Anthony P

    2010-01-01

    Aim: Prader-Willi syndrome (PWS) is a genetic disorder historically characterized by two phenotypic stages. The early phenotype in infants is associated with hypotonia, poor suck, and failure to thrive. In later childhood, PWS is associated with intellectual disability, hyperphagia, as well as growth and sex hormone deficiency. Little is known…

  8. A Comparative Study of Automated Infrasound Detectors - PMCC and AFD with Analyst Review.

    Energy Technology Data Exchange (ETDEWEB)

    Park, Junghyun; Hayward, Chris; Zeiler, Cleat; Arrowsmith, Stephen John; Stump, Brian

    2015-08-01

    Automated detections calculated by the progressive multi-channel correlation (PMCC) method (Cansi, 1995) and the adaptive F detector (AFD) (Arrowsmith et al., 2009) are compared to the signals identified by five independent analysts. Each detector was applied to a four-hour time sequence recorded by the Korean infrasound array CHNAR. This array was used because it is composed of both small (<100 m) and large (~1000 m) aperture element spacing. The four hour time sequence contained a number of easily identified signals under noise conditions that have average RMS amplitudes varied from 1.2 to 4.5 mPa (1 to 5 Hz), estimated with running five-minute window. The effectiveness of the detectors was estimated for the small aperture, large aperture, small aperture combined with the large aperture, and full array. The full and combined arrays performed the best for AFD under all noise conditions while the large aperture array had the poorest performance for both detectors. PMCC produced similar results as AFD under the lower noise conditions, but did not produce as dramatic an increase in detections using the full and combined arrays. Both automated detectors and the analysts produced a decrease in detections under the higher noise conditions. Comparing the detection probabilities with Estimated Receiver Operating Characteristic (EROC) curves we found that the smaller value of consistency for PMCC and the larger p-value for AFD had the highest detection probability. These parameters produced greater changes in detection probability than estimates of the false alarm rate. The detection probability was impacted the most by noise level, with low noise (average RMS amplitude of 1.7 mPa) having an average detection probability of ~40% and high noise (average RMS amplitude of 2.9 mPa) average detection probability of ~23%.

  9. Hundred years of history and the future of the Foundation 'Willie Commelin Scholten Phytopathological Laboratory'

    NARCIS (Netherlands)

    Schippers, B.; Roosje, G.S.

    1997-01-01

    The past More than a century ago, on December 18th, 1894, the Foundation 'Willie Commelin Scholten Phytopathological Laboratory', in short 'WCS-Foundation' (WCS) , was established in Amsterdam. It was one of the first institutes in the world dedicated to scientific research and higher

  10. Variation in form on the circle of Willis as studied by 3D-TOF MR angiography

    International Nuclear Information System (INIS)

    Hoshino, Haruhiko; Takagi, Makoto; Inafuku, Tetsuya; Adachi, Tomohide; Segawa, Hiroshi

    1996-01-01

    The circles of Willis in 2011 patients were examined by 3-dimensional time-of-flight MR angiography in order to evaluate the variations. The A1 segment of the anterior cerebral artery was not found in 4.8% on the right side and in 3.4% on the left side. In the older patients, MRA failed to demonstrate either the right or left A1 segment. A fetal configuration, whereby P1 segments had a smaller diameter than the posterior communicating artery and the posterior cerebral artery derived predominantly from the carotid artery, occurred in 19.8% on the right side and in 16.7% on the left side. MRA did not reveal the posterior communicating artery to be more common in the elderly. The circulatory states in the circle of Willis may alter with aging. (author)

  11. Prader–Willi syndrome: clinical problems in transition from pediatric to adult care

    OpenAIRE

    Crinò A; Fintini D; Bocchini S; Carducci C; Grugni G

    2016-01-01

    Antonino Crinò,1 Danilo Fintini,1 Sarah Bocchini,1 Chiara Carducci,1 Graziano Grugni,2 1Autoimmune Endocrine Diseases Unit, Bambino Gesù Children’s Hospital, Research Institute, Palidoro, Rome, 2Division of Auxology, Italian Auxological Institute, Research Institute, Piancavallo, Verbania, Italy Abstract: Prader–Willi syndrome (PWS) represents the most common form of genetic obesity. Thanks to the advances in medical care and technology, many persons with PWS li...

  12. Prader-Willi syndrome: a case report with atypical developmental features.

    Science.gov (United States)

    Sewaybricker, Letícia E; Guaragna-Filho, Guilherme; Paula, Georgette B; Andrade, Juliana G R; Tincani, Bruna J; D'Souza-Li, Lília; Lemos-Marini, Sofia H V; Maciel-Guerra, Andréa T; Guerra-Júnior, Gil

    2014-09-01

    To describe the case of a male Prader-Willi syndrome (PWS) patient with atypical development features. We report the case of a male adolescent with confirmed diagnosis of PWS which presents atypical phenotype. The patient progressed with spontaneous and complete pubertal development, stature in the normal range, and weight control without any pharmacological treatment, except metformin. PWS is an imprinting paternally inherited disorder of 15q11-13 characterized by hypotonia in infant age, hyperphagia, varied degrees of mental retardation, behavior problems, hypogonadism, short stature, and other less common findings.

  13. An obese young man with uncontrolled diabetes and insatiable hunger: Prader-Willi syndrome

    Directory of Open Access Journals (Sweden)

    Abilash Nair

    2013-01-01

    Full Text Available Prader-Willi syndrome (PWS is a rare cause of obesity. With the rising incidence of obesity, clinicians need to be aware of genetic causes of obesity and when to suspect them. A case of PWS, which was diagnosed in adulthood, has been discussed. This case is special because of lack of history of floppiness in infancy and predominance behavioral problems.

  14. Usefulness of 2D PC MRA of the circle of willis in the evaluation of acute cerebral infarction

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, Oh Han; Lee, Jae Hee; Kim, Ki Ju; Lee, Sung Yong [Our Lady of Mercy Hospital, Seoul (Korea, Republic of); Choi, Kyu Ho [The Catholic Univ. of Korea, Seoul (Korea, Republic of)

    1999-11-01

    To evaluate the usefulness of axial 2-D PC MRA of the circle of Willis in the evaluation of acute cerebral infarction We evaluated 42 patients with acute cerebral infarction who had undergone T2-weighted and diffusion weighted MR imaging (T2WI, DWI) and 2-D PC MRA of the circle of Willis within 72 hours of the onset of symptoms. In conjunction with high-signal lesions on DWI, the findings of 2-D PC MRA were classified as normal, stenotic, or indicative of arterial occlusion;negative 2-D PC MRA was not considered useful. In addition, the signal intensity of T2WI and DWI was compared. (The findings of 2-D PC MRA showed that 15 cases(35.7%) were normal, 13(31%) were stenotic, and that in 14 (33.3%), occlusion was present). Thus, 2-D PC MRA detected vascular abnormality in 27 cases(64.3%). On T2WI, six cases (14.3%) showed no signal change and 36(85.7%) showed high signal change. In six cases without signal change, MR images were obtained within 12 hours of ictus;in one of these patients MRA findings were normal, one had stenosis, and in four, occlusion was noted. 2-D PC MRA is a useful modality for the detection of vascular abnormality in patients with acute cerebral infarct.

  15. The dilemma of diagnostic testing for Prader-Willi syndrome

    Science.gov (United States)

    Hung, Dorothy

    2017-01-01

    Although Prader-Willi syndrome (PWS) is a well-described clinical dysmorphic syndrome, DNA testing is required for a definitive diagnosis. A definitive diagnosis can be made in approximately 99% of cases using DNA testing; there are a number of DNA tests that can be used for this purpose, although there is no set standard algorithm of testing. The dilemma arises because of the complex genetic mechanisms at the basis of PWS, which need to be elucidated. To establish the molecular mechanism with a complete work up, involves at least 2 tests. Here we discuss the commonly used tests currently available and suggest a cost—effective approach to diagnostic testing. PMID:28164030

  16. The effects of Bifidobacterium animalis ssp. lactis B94 on gastrointestinal wellness in adults with Prader-Willi syndrome: study protocol for a randomized controlled trial.

    Science.gov (United States)

    Alyousif, Zainab; Miller, Jennifer L; Sandoval, Mariana Y; MacPherson, Chad W; Nagulesapillai, Varuni; Dahl, Wendy J

    2018-04-27

    Constipation is a frequent problem in adults with Prader-Willi syndrome. Certain probiotics have been shown to improve transit and gastrointestinal symptoms of adults with functional constipation. The aim of this study is to determine the effect of daily consumption of Bifidobacterium animalis ssp. lactis B94 (B. lactis B94) on stool frequency, stool form, and gastrointestinal symptoms in adults with Prader-Willi syndrome. Adults with Prader-Willi syndrome (18-75 years old, n = 36) will be recruited and enrolled in a 20-week, randomized, double-blind, placebo-controlled, crossover study. Study subjects will be randomized to B. lactis B94 or placebo each for a 4-week period, preceded by a 4-week baseline and followed by 4-week washouts. Subjects will complete daily records of stool frequency and stool form (a proxy of transit time). Dietary intake data also will be collected. Stools, one in each period, will be collected for exploratory microbiota analyses. To our knowledge, this is the first randomized controlled trial evaluating the effectiveness of B. lactis in adults with Prader-Willi syndrome. The results of this study will provide evidence of efficacy for future clinical trials in patient populations with constipation. ClinicalTrials.gov ( NCT03277157 ). Registered on 08 September 2017.

  17. Premature Birth with Complicated Perinatal Course Delaying Diagnosis of Prader-Willi Syndrome

    Directory of Open Access Journals (Sweden)

    G. Ciana

    2011-01-01

    Full Text Available Prader-Willi syndrome in the newborn is essentially characterized by marked hypotonia, feeding difficulties, hypogonadism, and possible characteristic facial features. However, diagnosis at this age may be particularly difficult, and dysmorphic features may be subtle or absent. Prematurity can furthermore delay clinical features recognition and typical complications due to preterm birth may contribute to divert the diagnosis. We describe a preterm baby with a complicated perinatal course later diagnosed as PWS.

  18. Prader–Willi syndrome: clinical problems in transition from pediatric to adult care

    OpenAIRE

    Crinò, Antonino; Fintini,Danilo; Bocchini,Sarah; Carducci,Chiara; Grugni,Graziano

    2016-01-01

    Antonino Crinò,1 Danilo Fintini,1 Sarah Bocchini,1 Chiara Carducci,1 Graziano Grugni,2 1Autoimmune Endocrine Diseases Unit, Bambino Gesù Children’s Hospital, Research Institute, Palidoro, Rome, 2Division of Auxology, Italian Auxological Institute, Research Institute, Piancavallo, Verbania, Italy Abstract: Prader–Willi syndrome (PWS) represents the most common form of genetic obesity. Thanks to the advances in medical care and technology, many...

  19. Prader-Willi Critical Region, a Non-Translated, Imprinted Central Regulator of Bone Mass: Possible Role in Skeletal Abnormalities in Prader-Willi Syndrome.

    Directory of Open Access Journals (Sweden)

    Ee-Cheng Khor

    Full Text Available Prader-Willi Syndrome (PWS, a maternally imprinted disorder and leading cause of obesity, is characterised by insatiable appetite, poor muscle development, cognitive impairment, endocrine disturbance, short stature and osteoporosis. A number of causative loci have been located within the imprinted Prader-Willi Critical Region (PWCR, including a set of small non-translated nucleolar RNA's (snoRNA. Recently, micro-deletions in humans identified the snoRNA Snord116 as a critical contributor to the development of PWS exhibiting many of the classical symptoms of PWS. Here we show that loss of the PWCR which includes Snord116 in mice leads to a reduced bone mass phenotype, similar to that observed in humans. Consistent with reduced stature in PWS, PWCR KO mice showed delayed skeletal development, with shorter femurs and vertebrae, reduced bone size and mass in both sexes. The reduction in bone mass in PWCR KO mice was associated with deficiencies in cortical bone volume and cortical mineral apposition rate, with no change in cancellous bone. Importantly, while the length difference was corrected in aged mice, consistent with continued growth in rodents, reduced cortical bone formation was still evident, indicating continued osteoblastic suppression by loss of PWCR expression in skeletally mature mice. Interestingly, deletion of this region included deletion of the exclusively brain expressed Snord116 cluster and resulted in an upregulation in expression of both NPY and POMC mRNA in the arcuate nucleus. Importantly, the selective deletion of the PWCR only in NPY expressing neurons replicated the bone phenotype of PWCR KO mice. Taken together, PWCR deletion in mice, and specifically in NPY neurons, recapitulates the short stature and low BMD and aspects of the hormonal imbalance of PWS individuals. Moreover, it demonstrates for the first time, that a region encoding non-translated RNAs, expressed solely within the brain, can regulate bone mass in health

  20. The GH/IGF-I axis and pituitary function and size in adults with Prader-Willi syndrome

    NARCIS (Netherlands)

    van Nieuwpoort, I.C.; Sinnema, M.; Castelijns, J.A.; Twisk, J.W.; Curfs, L.M.; Drent, M.L.

    2011-01-01

    Background: In adults with Prader-Willi syndrome (PWS), limited information is available about pituitary function, more specifically the prevalence of growth hormone deficiency (GHD). The aim of this study was to gain more insight into endocrine function in PWS adults, with emphasis on GH secretion.

  1. Spectral analyses of the Forel-Ule Ocean colour comparator scale

    NARCIS (Netherlands)

    Wernand, M.; van der Woerd, H.J.

    2010-01-01

    François Alphonse Forel (1890) and Willi Ule (1892) composed a colour comparator scale, with tints varying from indigo-blue to cola brown, to quantify the colour of natural waters, like seas, lakes and rivers. For each measurement, the observer compares the colour of the water above a submersed

  2. Detector simulation needs for detector designers

    International Nuclear Information System (INIS)

    Hanson, G.G.

    1987-11-01

    Computer simulation of the components of SSC detectors and of the complete detectors will be very important for the designs of the detectors. The ratio of events from interesting physics to events from background processes is very low, so detailed understanding of detector response to the backgrounds is needed. Any large detector for the SSC will be very complex and expensive and every effort must be made to design detectors which will have excellent performance and will not have to undergo major rebuilding. Some areas in which computer simulation is particularly needed are pattern recognition in tracking detectors and development of shower simulation code which can be trusted as an aid in the design and optimization of calorimeters, including their electron identification performance. Existing codes require too much computer time to be practical and need to be compared with test beam data at energies of several hundred GeV. Computer simulation of the processing of the data, including electronics response to the signals from the detector components, processing of the data by microprocessors on the detector, the trigger, and data acquisition will be required. In this report we discuss the detector simulation needs for detector designers

  3. Functional Assessment and Behavioral Treatment of Skin Picking in a Teenage Girl With Prader-Willi Syndrome

    NARCIS (Netherlands)

    Radstaake, M.; Didden, H.C.M.; Bolio, M.M.L.; Lang, R.B.; Lancioni, G.E.; Curfs, L.M.G.

    2011-01-01

    Skin picking is common in individuals with Prader-Willi Syndrome (PWS) but few treatment studies exist. This study reports the successful functional behavioral assessment (FBA) and treatment of skin picking in a 16-year-old female with PWS. A treatment package based on FBA results consisted of

  4. Collateral configuration of the circle of Willis: transcranial color-coded duplex ultrasonography and comparison with postmortem anatomy

    NARCIS (Netherlands)

    Hoksbergen, A. W.; Fülesdi, B.; Legemate, D. A.; Csiba, L.

    2000-01-01

    BACKGROUND AND PURPOSE: The anterior communicating artery (AcoA) and posterior communicating arteries (PcoA) of the circle of Willis provide the main route for collateral blood flow in cases of carotid artery obstruction. Transcranial color-coded duplex ultrasonography (TCCD) allows real-time

  5. Cognitive, Emotional, Physical and Social Effects of Growth Hormone Treatment in Adults with Prader-Willi Syndrome

    Science.gov (United States)

    Hoybye, C; Thoren, M.; Bohm, B.

    2005-01-01

    Prader-Willi syndrome (PWS) is a multisystem genetic disorder characterized by short stature, muscular hypotonia, hyperphagia, obesity, maladaptive behaviour, hypogonadism and partial growth hormone (GH) deficiency (GHD). Severe GHD of other aetiologies has been shown to affect mood and quality of life negatively, and there are reports of…

  6. Sedation in a Patient with Prader-Willi Syndrome: A Case Report

    Directory of Open Access Journals (Sweden)

    Hayrettin Daşkaya

    2014-12-01

    Full Text Available Prader-Willi syndrome (PWS is a rare disorder characterized by hypotonia, growth retardation, characteristic face shape, hypogonadism, hyperphagia and related morbid obesity. Anesthesia application in these patients has increased risk of peroperative complication due the central hypotonia, abnormal teeth structure, and limited neck mobility. Therefore, clinicians should be prepared for the worst scenario before anesthesia application in patients with PWS during general or out-patient surgery. Here, in this case report, outpatient anesthesia performed in a patient with PWS for diagnostic electromyography is presented with the literature review.

  7. A variety of genetic mechanisms are associated with the Prader-Willi syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Woodage, T.; Deng, Z.M.; Prasad, M. [Royal Prince Alfred Hospital, Camperdown (Australia)] [and others

    1994-09-15

    An extensive set of chromosome 15 DNA polymorphisms and densitometric analysis with four markers mapping to the Prader-Willi chromosome region (PWCR) of chromosome 15 have been used to characterize a cohort of 30 subjects with classical Prader-Willi syndrome (PWS). Molecular analysis enabled the classification of the PWS subjects into four groups: (A) 18 subjects (60%) had deletions of paternal 15q11-13 involving a common set of DNA markers. Two subjects had differently sized deletions, one larger and one smaller than the other cases. (B) Eight (27%) had maternal uniparental disomy for chromosome 15. (C) One (3%) had a marker chromosome carrying an extra copy of the PWCR. The marker chromosome was demonstrated to be of paternal origin and the two intact chromosomes were maternally derived. This case represents an apparent exception to the generally held view that PWS is associated with an absence of paternally inherited gene(s) located in the PWCR. (D) The remaining three cases (10%) had none of the above abnormalities. This last subgroup of patients has not previously been well characterized but could represent limited deletions not detectable with the markers used or abnormalities in the imprinting process. These cases represent potentially valuable resources to elucidate more precisely the fundamental disorders responsible for PWS. 39 refs., 2 figs., 3 tabs.

  8. Comparing interaction rate detectors for weakly interacting massive particles with annual modulation detectors

    International Nuclear Information System (INIS)

    Copi, Craig J.; Krauss, Lawrence M.

    2003-01-01

    We compare the sensitivity of WIMP detection via direct separation of possible signal versus background to WIMP detection via detection of an annual modulation, in which signal and background cannot be separated on an event-by-event basis. In order to determine how the constraints from the two different types of experiments might be combined an adequate incorporation of uncertainties due to galactic halo models must be made. This issue is particularly timely in light of recent direct detection limits from Edelweiss and CDMS, which we now demonstrate cannot be made consistent with the most recent claimed DAMA annual modulation observation by including halo uncertainties for spin independent interactions. On the other hand, we demonstrate that a combination of these two techniques, in the event of any positive direct detection signal, could ultimately allow significant constraints on anisotropic halo models even without directional sensitivity in these detectors

  9. Reduced cortical complexity in children with prader-willi syndrome and its association with cognitive impairment and developmental delay

    NARCIS (Netherlands)

    A. Lukoshe (Akvile); A.C.S. Hokken-Koelega (Anita); A. van der Lugt (Aad); T.J.H. White (Tonya)

    2014-01-01

    textabstractBackground: Prader-Willi Syndrome (PWS) is a complex neurogenetic disorder with symptoms involving not only hypothalamic, but also a global, central nervous system dysfunction. Previously, qualitative studies reported polymicrogyria in adults with PWS. However, there have been no

  10. 'A one-sided affair': unilateral pulmonary oedema and the role of cardiac MRI in diagnosing premature coronary artery disease in a patient with Prader-Willi syndrome.

    Science.gov (United States)

    Jabbar, Avais; Khan, Jamal N; Singh, Anvesha; McCann, Gerry P

    2013-05-22

    There is no formal association between premature coronary artery disease (CAD) and Prader-Willi syndrome despite its association with hyperlipidaemia, diabetes mellitus and hypertension. A 36-year-old man with Prader-Willi syndrome presented with acute breathlessness. Inflammatory markers were borderline elevated and chest radiography demonstrated unilateral diffuse alveolar shadowing. Bronchopneumonia was diagnosed and despite treatment with multiple courses of antimicrobial therapy, there was minimal symptomatic and radiographical improvement. A diagnosis of unilateral pulmonary oedema was suspected. Echocardiography was non-diagnostic due to body habitus and coronary angiography was deemed inappropriate due to uncertainty in diagnosis, invasiveness and pre-existing chronic kidney disease. Therefore, cardiac magnetic resonance was performed, confirming severe triple-vessel CAD. This case demonstrates a presentation of heart failure with unilateral chest radiograph changes in a young patient with Prader-Willi syndrome and severe premature CAD detected by multiparametric cardiac magnetic resonance imaging.

  11. O atleta olímpico brasileiro Willy Seewald: memórias do primeiro recordista nacional do lançamento de dardo

    Directory of Open Access Journals (Sweden)

    Janice Zarpellon Mazo

    2012-09-01

    Full Text Available O presente estudo registra a trajetória do atleta Willy Seewald, que se destacou no cenário esportivo sul-rio-grandense, nacional, e ainda teve uma participação nos Jogos Olímpicos de 1924, em Paris, na prova de lançamento de dardo. Para este estudo histórico foram consultados jornais, revistas, e documentos de acervo pessoal, além da produção de fontes orais por meio da gravação de entrevistas com familiares do atleta. A trajetória de Willy nos mostra que, para ser considerado um cavalheiro praticante do "bom esporte", no Brasil, os requisitos diferiam dos exigidos na Europa.

  12. IGF-1 levels, complex formation, and IGF bioactivity in growth hormone-treated children with Prader-Willi syndrome

    NARCIS (Netherlands)

    Bakker, N. E.; Van Doorn, J.; Renes, J. S.; Donker, G. H.; Hokken-Koelega, A. C S

    2015-01-01

    Context: Children with Prader-Willi syndrome (PWS) attain high-serum immunoreactive IGF-1 levels during a standard-dose GH treatment, which leads to concern, but lowering the dose deteriorates their body composition. Objective: The objective of the study was to evaluate serum IGF-1, IGF binding

  13. Clinical Management of a Child with Prader-Willi Syndrome from Maternal Uniparental Disomy (UPD) Genetic Inheritance

    Science.gov (United States)

    Bellon-Harn, Monica L.

    2005-01-01

    Prader-Willi Syndrome (PWS) is reported in 1 in 10,000-15,000 individuals. Unfortunately, many cases are missed due to clinicians' lack of familiarity with the syndrome as well as clinical and laboratory diagnostic criteria. Although common clinical characteristics are reported, variety exists in the nature and severity of dysfunction associated…

  14. READING WILLY WONKA IN THE ERA OF ANTI-THINKING.

    Science.gov (United States)

    Miller, Ian S

    2018-04-11

    Whether encountered as a movie or novel, Roald Dahl's Charlie and the Chocolate Factory is a childhood staple of postwar Anglophone culture. Originally published in 1964, Dahl's story of "Willie Wonka" is a morality tale for our times addressed by the present essay in relation to the precariousness, violence, intergenerational faith, and materialist fantasies reflective of contemporary life in the early twenty-first century. Compensating for the precarity of contemporary life's impoverishment as assumptions of societal stability are overthrown, this chronicle of the Bucket family details: envious desire validated by large group chosen trauma; authoritarian enslavement of inferior, colonized peoples with murderous, industrial-level human experimentation; toward gratification of the greedy fantasy of unlimited sweetness under the sway of lethal identification with the aggressor.

  15. Divergent structural brain abnormalities between different genetic subtypes of children with Prader–Willi syndrome

    OpenAIRE

    Lukoshe, Akvile; White, Tonya; Schmidt, Marcus N; van der Lugt, Aad; Hokken-Koelega, Anita C

    2013-01-01

    Background Prader–Willi syndrome (PWS) is a complex neurogenetic disorder with symptoms that indicate not only hypothalamic, but also a global, central nervous system (CNS) dysfunction. However, little is known about developmental differences in brain structure in children with PWS. Thus, our aim was to investigate global brain morphology in children with PWS, including the comparison between different genetic subtypes of PWS. In addition, we performed exploratory cortical and subcortical foc...

  16. Thoughts on the behavioural phenotypes in Prader-Willi syndrome and velo-cardio-facial syndrome: A novel approach

    NARCIS (Netherlands)

    Verhoeven, W.M.A.; Egger, J.I.M.; Tuinier, S.

    2007-01-01

    In both Prader-Willi syndrome (PWS) and 22q11 deletion syndrome [velo-cardio-facial syndrome (VCFS)], an increased risk for psychotic disorders is reported, which are as a rule not included in the behavioural phenotype of these two syndromes. For the description of a behavioural phenotype, the

  17. Collateral variations in circle of willis in atherosclerotic population assessed by means of transcranial color-coded duplex ultrasonography

    NARCIS (Netherlands)

    Hoksbergen, A. W.; Legemate, D. A.; Ubbink, D. T.; Jacobs, M. J.

    2000-01-01

    BACKGROUND AND PURPOSE: Transcranial color-coded duplex ultrasonography combined with common carotid artery (CCA) compression can be used to assess the collateral function of the circle of Willis. The aim of this study was to assess the unknown fraction of hemodynamic functional anterior and

  18. The use of medical care and the prevalence of serious illness in an adult Prader-Willi syndrome cohort

    NARCIS (Netherlands)

    Sinnema, M.; Maaskant, M.A.; Schrojenstein Lantman-de Valk, H.M. van; Boer, H. de; Curfs, L.M.G.; Schrander-Stumpel, C.T.R.M.

    2013-01-01

    INTRODUCTION: Adults with Prader-Willi syndrome (PWS) have an increased occurrence of several medical conditions. We report on the consequences of high morbidity rates such as prevalence rate of hospital admissions, medication use and surgery in a Dutch cohort of adults with PWS. Special attention

  19. Gastric Dilatation and Abdominal Compartment Syndrome in a Child with Prader-Willi Syndrome.

    Science.gov (United States)

    Blat, Clara; Busquets, Elisenda; Gili, Teresa; Caixàs, Assumpta; Gabau, Elisabeth; Corripio, Raquel

    2017-06-07

    BACKGROUND Prader-Willi syndrome (PWS) is a genetic disorder characterized by initial muscular hypotonia and feeding difficulties, and later an insatiable appetite, hyperphagia and obesity along with mild to moderate intellectual impairment. Affected individuals' food-seeking behavior and suspected delayed gastric emptying can lead to gastric dilatation with subsequent necrosis and perforation. CASE REPORT We present the case of a 5-year-old boy diagnosed with Prader-Willi syndrome at neonatal age due to muscular hypotonia, who started growth hormone therapy at 20 months. He presented with two episodes of a rapidly progressing gastric dilatation that led to abdominal hypertension and secondary shock at the age of 2 and 5. No large amount of food was eaten before any of the episodes, and he had abdominal pain and vomiting on both occasions. On arrival at the emergency room, a nasogastric tube was placed and aspiration of food material was performed. Abdominal X-ray and CT scan revealed massive gastric dilatation. He was admitted at the Pediatric Intensive Care Unit and after a variable period of fasting, tolerated oral intake and could be discharged. CONCLUSIONS Gastric dilatation due to gastroparesis in PWS is a rare complication. However, it is a life-threatening situation and physicians should therefore maintain a high level of suspicion for gastric dilatation when patients present with warning symptoms such as abdominal pain or discomfort and vomiting.

  20. Caracterización clínico genética del síndrome Prader Willi

    Directory of Open Access Journals (Sweden)

    Anitery Travieso Tellez

    2014-12-01

    Full Text Available Introducción: el síndrome Prader Willi es un desorden genético causado por la pérdida de genes contenidos en la región 15q11-q13 del cromosoma paterno. Objetivo: describir las características clínicas y genéticas de los pacientes con síndrome Prader Willi. Material y método: se realizó un estudio descriptivo, de corte transversal, con el universo de 15 pacientes con sospecha de síndrome Prader Willi remitidos a consulta provincial de Genética Clínica durante el año 2013. Se consideraron como variables clínicas los criterios diagnósticos según Holms, y como variables genéticas los resultados de los estudios cromosómicos y moleculares. Resultados: predominó el sexo femenino en un 66.7%. Las edades estuvieron entre los tres y los 41 años. Los criterios mayores más frecuentes resultaron la obesidad troncular y el retraso del neurodesarrollo en el 100% de los pacientes. Los criterios menores más identificados fueron los disturbios del sueño y las dificultades del lenguaje con un 66.7% cada uno. En ninguno de los casos se detectaron anomalías cromosómicas por cariotipificación. Tres pacientes (60% presentaron la deleción a nivel de la región 15q11-q13 identificada por la técnica de hibridación in sito con fluorescencia. Conclusiones: la definición del diagnóstico en la provincia resulta demorada. Se requiere de reevaluación según los criterios clínicos en las diferentes etapas de la vida para diagnóstico de certeza. La presencia de hipotonía neonatal y dificultades en la alimentación son elementos asociados al diagnóstico por deleción 15q11-q13.

  1. Clinical features and molecular genetic analysis of a boy with Prader-Willi syndrome caused by an imprinting defect

    DEFF Research Database (Denmark)

    Schulze, A; Hansen, Claus; Baekgaard, P

    1997-01-01

    Prader-Willi syndrome (PWS) is a neuroendocrine disorder caused by a non-functioning paternally derived gene(s) within the chromosome region 15q11-q13. Most cases result from microscopically visible deletions of paternal origin, or maternal uniparental disomy of chromosome 15. In both instances n...

  2. Influence of Gender and Age on Average Dimensions of Arteries Forming the Circle of Willis Study by Magnetic Resonance Angiography on Kosovo's Population.

    Science.gov (United States)

    Shatri, Jeton; Bexheti, Dorentina; Bexheti, Sadi; Kabashi, Serbeze; Krasniqi, Shaip; Ahmetgjekaj, Ilir; Zhjeqi, Valbona

    2017-10-15

    Circulus arteriosus cerebri is the main source of blood supply to the brain; it connects the left and right hemispheres with anterior and posterior parts. Located at the interpenducular fossa at the base of the brain the circle of Willis is the most important source of collateral circulation in the presence of the disease in the carotid or vertebral artery. The purpose of the research is to study the diameter and length of arteries and provide an important source of reference on Kosovo's population. This is an observative descriptive study performed at the University Clinical Center of Kosovo. A randomised sample of 133 angiographic examinations in adult patients of both sexes who were instructed to exploration is included. The diameters and lengths measured in our study were comparable with other brain-cadaver studies especially those performed by MRA. All dimensions of the arteries are larger in male than female, except the diameter of PCoA that is larger in female (p < 0.05) and length of the ACoA (p < 0.05). Significant differences were found in diameters of arteries between the younger and the older age groups. Knowing the dimensions of the arteries of the circle of Willis has a great importance in interventional radiology as well as during anatomy lessons.

  3. Food addiction and cues in prader-willi syndrome.

    Science.gov (United States)

    von Deneen, Karen M; Gold, Mark S; Liu, Yijun

    2009-03-01

    Obesity research has recognized that there are many factors contributing to this devastating disorder. Much debate has arisen among scientists to develop models that might be useful in understanding why obesity has become a major health problem and epidemic. However, much of the current debate has been fractious and causes of obesity have been attributed solely to behavior or fast food, personality issues, depression, addiction, or genetics. One of the neurohormonal and genetic causes has been found in Prader-Willi syndrome (PWS), which results in excessive, pathologic reinforcement of food. We have studied PWS to delineate the neurobiology so that environmental cue stimulation may be explained for PWS. Neuroimaging studies have shown that appetizing food and food cues are associated with appetite stimulation. Appetite control is poor in PWS, thus food cues play a major role in its regulation. Hence, PWS may be the genetic model of choice for obesity.

  4. 20 years of cosmic muons research performed in IFIN-HH

    Energy Technology Data Exchange (ETDEWEB)

    Mitrica, Bogdan [Horia Hulubei National Institute of Physics and Nuclear Engineering - IFIN HH, Bucharest, P.O.B.MG-6 (Romania)

    2012-11-20

    During the last two decades a modern direction in particle physics research has been developed in IFIN-HH Bucharest, Romania. The history started with the WILLI detector built in IFIN-HH Bucharest in collaboration with KIT Karlsruhe (formerly Forschungszentrum Karlsruhe). The detector was designed for measurements of the low energy muon charge ratio (< 1GeV) based on a delayed coincidence method, measuring the decay time of the muons stopped in the detector: the positive muons decay freely, but the negative muons are captured in the atom thus creating muonic atoms and decay depending on the nature of the host atom. In a first configuration, the WILLI detector was placed in a fixed position for measuring vertical muons. Further WILLI has been transformed in a rotatable device which allows directional measurements of muon charge ratio and muon flux. The results exhibit a pronounced azimuthal asymmetry (East-West effect) due to the different in fluence of the geomagnetic field on the trajectories of positive and negative muons in air. In parallel, flux measurement, taking into account muon events with nergies > 0.4GeV, show a diurnal modulation of the muon flux. The analysis of the muon events for energies < 0.6GeV reveals an aperiodic variation of the muon flux. A new detection system performing coincidence measurements between the WILLI calorimeter and a small array of 12 scintillators plates has been installed in IFIN-HH starting from the autumn of 2010. The aim of the system is to investigate muon charge ratio from individual EAS by using the mini-array as trigger for the WILLI calorimeter. Such experimental studies could provide detailed information on hadronic interaction models and primary cosmic ray composition at energies around 10{sup 15}eV. Simulation studies and preliminary experimental tests, regarding the performances of the mini-array, have been performed using H and Fe primaries, with energies in a range 10{sup 13}eV - 10{sup 15}eV. The results show

  5. Treatment of carotid-siphon aneurysms by using willis stent-graft: an angiographic and histopathologic study in dogs

    International Nuclear Information System (INIS)

    Zhu Yueqi; Li Minghua; Xie Jian; Tan Huaqiao; Cheng Yingsheng; Wang Jianbo

    2010-01-01

    Objective: To establish a carotid siphon aneurysm model in dogs in order to test the mechanical features of a newly-designed Willis covered stent-graft and to investigate the histological reaction of the stent-implanted vessel during a follow-up period of 12 months. Methods: Twenty-four saccular sidewall aneurysms were surgically created in twelve dogs (group A) and 12 carotid siphon aneurysms in another twelve dogs (group B). A Willis stent-graft was implanted in each aneurysm. Angiography was performed immediately after the procedure and 1, 3, 6 and 12 months after the implantation to investigate the aneurysm isolation, endoleak, stent angulation, and the patency or restenosis of the parent artery. Light and scanning electronic microscopy were used to identify aneurysmal sac thrombi, intima hyperplasia and endothelial progress of the stent-loaded arterial segment. Results: In group B, postoperative immediate angiography demonstrated that two aneurysms had mild endoleak and three stents became angulated. Follow-up exam 12 months after the procedure revealed that all previous endoleaks disappeared, one parent artery became occluded and three parent arteries developed mild stenosis (< 50%). In group A, occlusion of parent artery was seen in one and mild stenosis (< 50%) in 2 cases. Electronic microscopy revealed new intima formation in all stents, and all aneurysmal sacs were filled with thrombi. In group B, the endothelialization process was not completed until 12 months after the stent implantation, and a marked correlation existed between endothelial cell arrangement and the hemodynamic orientation. Conclusion: It is feasible to treat carotid-siphon aneurysm in dog with a Willis stent-graft. The complete endothelialization of the covered stent in tortuous vessel takes longer time than that in rather straight vessel. (authors)

  6. A Paternally Inherited Duplication in the Prader-Willi/Angelman Syndrome Critical Region: A Case and Family Study

    Science.gov (United States)

    Veltman, Marijcke W. M.; Thompson, Russell J.; Craig, Ellen E.; Dennis, Nicholas R.; Roberts, Sian E.; Moore, Vanessa; Brown, Josie A.; Bolton, Patrick F.

    2005-01-01

    The Prader-Willi/Angelman Critical Region (PWACR; Chromosome 15q11-13) is of interest as a potential locus for genes conferring susceptibility to autism spectrum disorders (ASD). This report describes a female proband referred for evaluation of a possible ASD. Genetic analyses indicated that the proband, her father and one of her sisters, carried…

  7. Prader–Willi syndrome: clinical problems in transition from pediatric to adult care

    Directory of Open Access Journals (Sweden)

    Crinò A

    2016-07-01

    Full Text Available Antonino Crinò,1 Danilo Fintini,1 Sarah Bocchini,1 Chiara Carducci,1 Graziano Grugni,2 1Autoimmune Endocrine Diseases Unit, Bambino Gesù Children’s Hospital, Research Institute, Palidoro, Rome, 2Division of Auxology, Italian Auxological Institute, Research Institute, Piancavallo, Verbania, Italy Abstract: Prader–Willi syndrome (PWS represents the most common form of genetic obesity. Thanks to the advances in medical care and technology, many persons with PWS live longer and survive to adulthood. Currently, because of the many physical and behavioral manifestations, transitional health care is not easy for these patients and is considered a very important issue. Moreover, very few studies have examined these transitional problems in young adults with PWS. In recent years, there has been great interest in improving transition planning and support for young people with PWS reaching adulthood. In this article, we underline the main clinical problems in transition and give some advice to make this period less difficult and easier for adolescents with PWS. Special attention should be paid to obesity, diabetes mellitus, hypertension, osteoporosis, and sleep apnea during the period of transition. In PWS, for an effective transition from childhood to adulthood, a multidisciplinary team is needed, and should maintain the same approach to food, environment, and psychiatric issues. For comprehensive care, it is necessary to involve adult endocrinologists and other medical specialists in conjunction with the pediatric team. Parental involvement is, however, a great help for supervising adolescents with PWS during this particular period. Keywords: Prader–Willi, transition period, intellectual disabilities

  8. De como La Llorona se tornou um Miserere de Willy Corrêa de Oliveira How La llorona became a Miserere by Willy Corrêa de Oliveira

    Directory of Open Access Journals (Sweden)

    Mauricio De Bonis

    2013-06-01

    Full Text Available Em nossa pesquisa sobre o ciclo de peças para piano Miserere, de Willy Corrêa de Oliveira (DE BONIS, 2010 discutimos uma série de procedimentos composicionais pertinentes a essa obra e à produção do compositor em geral, a saber: a metalinguagem, a relação com as artes plásticas, a condensação de ideias, a superposição de citações à maneira de um ideograma, o teatro musical, e a possibilidade de uma análise estrutural de cada peça ao lado de uma leitura semântica (incentivada pela própria partitura. Obra aberta, o Miserere tem recebido adições do compositor após a publicação da pesquisa. As mesmas ferramentas de análise aplicadas para o ciclo todo são aqui utilizadas para o estudo de uma das últimas peças a serem acrescentadas, em 2009.In our research on the cycle of piano pieces called Miserere, by Brazilian composer Willy Corrêa de Oliveira (DE BONIS, 2010 we discuss a series of compositional procedures used in this work and in the composer's production in general, such as borrowings and metalanguage, the relation to visual arts, the condensation of ideas, the superposition of quotations in the manner of an ideogram, musical theater, and the possibility of an structural analysis of each piece side by side with a semantic reading (favored by the score itself. As an open work, the Miserere has received additions by the composer after the publication of this research. The same analytical tools applied to the cycle are here used to study one of the last pieces to join the cycle in 2009.

  9. Randomized controlled trial to investigate the effects of growth hormone treatment on scoliosis in children with Prader-Willi syndrome.

    NARCIS (Netherlands)

    Lind van Wijngaarden, R.F. de; Klerk, L.W. de; Festen, D.A.M.; Duivenvoorden, H.J.; Otten, B.J.; Hokken-Koelega, A.C.S.

    2009-01-01

    CONTEXT: The prevalence of scoliosis in children with Prader-Willi syndrome (PWS) is 30-80%, depending on age. Although reports about effects of GH treatment on scoliosis in children with PWS are limited, scoliosis is generally considered a contraindication for GH treatment. OBJECTIVE: The aim was

  10. Comparative Sensitivities of Gravitational Wave Detectors Based on Atom Interferometers and Light Interferometers

    Science.gov (United States)

    Baker, John G.; Thorpe, J. I.

    2012-01-01

    We consider a class of proposed gravitational wave detectors based on multiple atomic interferometers separated by large baselines and referenced by common laser systems. We compute the sensitivity limits of these detectors due to intrinsic phase noise of the light sources, non-inertial motion of the light sources, and atomic shot noise and compare them to sensitivity limits for traditional light interferometers. We find that atom interferometers and light interferometers are limited in a nearly identical way by intrinsic phase noise and that both require similar mitigation strategies (e.g. multiple arm instruments) to reach interesting sensitivities. The sensitivity limit from motion of the light sources is slightly different and favors the atom interferometers in the low-frequency limit, although the limit in both cases is severe. Whether this potential advantage outweighs the additional complexity associated with including atom interferometers will require further study.

  11. Simulation study comparing the helmet-chin PET with a cylindrical PET of the same number of detectors

    Science.gov (United States)

    Ahmed, Abdella M.; Tashima, Hideaki; Yoshida, Eiji; Nishikido, Fumihiko; Yamaya, Taiga

    2017-06-01

    There is a growing interest in developing brain PET scanners with high sensitivity and high spatial resolution for early diagnosis of neurodegenerative diseases and studies of brain functions. Sensitivity of the PET scanner can be improved by increasing the solid angle. However, conventional PET scanners are designed based on a cylindrical geometry, which may not be the most efficient design for brain imaging in terms of the balance between sensitivity and cost. We proposed a dedicated brain PET scanner based on a hemispheric shape detector and a chin detector (referred to as the helmet-chin PET), which is designed to maximize the solid angle by increasing the number of lines-of-response in the hemisphere. The parallax error, which PET scanners with a large solid angle tend to have, can be suppressed by the use of depth-of-interaction detectors. In this study, we carry out a realistic evaluation of the helmet-chin PET using Monte Carlo simulation based on the 4-layer GSO detector which consists of a 16  ×  16  ×  4 array of crystals with dimensions of 2.8  ×  2.8  ×  7.5 mm3. The purpose of this simulation is to show the gain in imaging performance of the helmet-chin PET compared with the cylindrical PET using the same number of detectors in each configuration. The sensitivity of the helmet-chin PET evaluated with a cylindrical phantom has a significant increase, especially at the top of the (field-of-view) FOV. The peak-NECR of the helmet-chin PET is 1.4 times higher compared to the cylindrical PET. The helmet-chin PET provides relatively low noise images throughout the FOV compared to the cylindrical PET which exhibits enhanced noise at the peripheral regions. The results show the helmet-chin PET can significantly improve the sensitivity and reduce the noise in the reconstructed images.

  12. A Novel Pairwise Comparison-Based Method to Determine Radiation Dose Reduction Potentials of Iterative Reconstruction Algorithms, Exemplified Through Circle of Willis Computed Tomography Angiography.

    Science.gov (United States)

    Ellmann, Stephan; Kammerer, Ferdinand; Brand, Michael; Allmendinger, Thomas; May, Matthias S; Uder, Michael; Lell, Michael M; Kramer, Manuel

    2016-05-01

    The aim of this study was to determine the dose reduction potential of iterative reconstruction (IR) algorithms in computed tomography angiography (CTA) of the circle of Willis using a novel method of evaluating the quality of radiation dose-reduced images. This study relied on ReconCT, a proprietary reconstruction software that allows simulating CT scans acquired with reduced radiation dose based on the raw data of true scans. To evaluate the performance of ReconCT in this regard, a phantom study was performed to compare the image noise of true and simulated scans within simulated vessels of a head phantom. That followed, 10 patients scheduled for CTA of the circle of Willis were scanned according to our institute's standard protocol (100 kV, 145 reference mAs). Subsequently, CTA images of these patients were reconstructed as either a full-dose weighted filtered back projection or with radiation dose reductions down to 10% of the full-dose level and Sinogram-Affirmed Iterative Reconstruction (SAFIRE) with either strength 3 or 5. Images were marked with arrows pointing on vessels of different sizes, and image pairs were presented to observers. Five readers assessed image quality with 2-alternative forced choice comparisons. In the phantom study, no significant differences were observed between the noise levels of simulated and true scans in filtered back projection, SAFIRE 3, and SAFIRE 5 reconstructions.The dose reduction potential for patient scans showed a strong dependence on IR strength as well as on the size of the vessel of interest. Thus, the potential radiation dose reductions ranged from 84.4% for the evaluation of great vessels reconstructed with SAFIRE 5 to 40.9% for the evaluation of small vessels reconstructed with SAFIRE 3. This study provides a novel image quality evaluation method based on 2-alternative forced choice comparisons. In CTA of the circle of Willis, higher IR strengths and greater vessel sizes allowed higher degrees of radiation dose

  13. Evaluating How Circle of Willis Topology Affects Embolus Distribution in the Brain

    Science.gov (United States)

    Jani, Neel; Mukherjee, Debanjan; Shadden, Shawn

    2016-11-01

    Embolic stroke occurs when fragmented cellular or acellular material (emboli) travels to the brain to occlude an artery. Understanding the transport of emboli across unsteady, pulsatile flow in complex arterial geometries is challenging and influenced by a range of factors, including patient anatomy. The work herein develops the modeling and mechanistic understanding of how embolus transport is affected by the arterial connections at the base of the brain known as the Circle of Willis (CoW). A majority of the human population has an incomplete CoW anatomy, with connections either missing or ill-developed. We employ numerical simulations combining image-based modeling, computational fluid dynamics, discrete particle dynamics, and a sampling based analysis to compare collateral flow through the most prevalent CoW topologies, to determine embolus distribution fractions among vessels in the CoW, and to investigate the role of inertial effects in causing differences in flow and embolus distribution. The computational framework developed enables characterization of the complex interplay of anatomy, hemodynamics, and embolus properties in the context of embolic stroke as well as statistical analysis of embolism risks across common CoW variations.

  14. Comparative study between c-Si and CZT semiconducting detectors using the mathematical simulation of the radiation transport through matter

    International Nuclear Information System (INIS)

    Dona, O.; Leyva, A.; Pinera, I.; Abreu, Y.; Cruz, C.

    2007-01-01

    Using the code system MCNP-X, based on the Monte Carlo statistical method, a comparative study of some properties of the crystalline silicon and CZT semiconducting detectors was carried out. This program, conceived to simulate the transport of several types of particles through matter, allowed the study of spatial distribution of the radiation energy deposition in detectors and evaluate the devices quantum efficiency. A quantitative estimation of the number of charge carriers generated in active zone of the detector was also presented. The results of the displacement cross sections calculation and the devices resistance to the radiacional damage are discussed. (Author)

  15. Parental Ratings of Children and Adolescents with Prader-Willi Syndrome on the Behavior Rating Inventory of Executive Function (BRIEF)

    Science.gov (United States)

    Hutchison, Marnie; Pei, Jacqueline; Leung, Wing Sze Wence; Mackenzie, Michelle; Hicks, Melanie D.; Thurm, Audrey E.; Han, Joan C.; Haqq, Andrea M.

    2015-01-01

    We investigated executive functioning in 25 children and adolescents with Prader-Willi syndrome (PWS) on the Behavior Rating Inventory of Executive Function (BRIEF). Significant deficits emerged, with mean scores on all but two scales reaching levels of clinical significance (T score = 65). Older children tended to have higher scores than younger…

  16. Growth Hormone Therapy in Adults with Prader-Willi Syndrome

    Directory of Open Access Journals (Sweden)

    Karen S. Vogt

    2015-04-01

    Full Text Available Prader-Willi syndrome (PWS is characterized by hyperphagia, obesity if food intake is not strictly controlled, abnormal body composition with decreased lean body mass and increased fat mass, decreased basal metabolic rate, short stature, low muscle tone, cognitive disability, and hypogonadism. In addition to improvements in linear growth, the benefits of growth hormone therapy on body composition and motor function in children with PWS are well established. Evidence is now emerging on the benefits of growth hormone therapy in adults with PWS. This review summarizes the current literature on growth hormone status and the use of growth hormone therapy in adults with PWS. The benefits of growth hormone therapy on body composition, muscle strength, exercise capacity, certain measures of sleep-disordered breathing, metabolic parameters, quality of life, and cognition are covered in detail along with potential adverse effects and guidelines for initiating and monitoring therapy.

  17. Nutritient intake of young children with Prader–Willi syndrome

    Directory of Open Access Journals (Sweden)

    Marianne Lindmark

    2010-03-01

    Full Text Available Background: Prader–Willi syndrome (PWS is a rare genetic disorder resulting in obesity. The diets for young children with PWS must balance the importance of preventing development of obesity with the need to supply sufficient energy and essential nutrients. Objective: To investigate the nutritional intake for children with PWS 2, 3, and 4 years of age and compare it with Nordic Nutritional Recommendations (NNR and intake of healthy controls. Design: Assessments of food intake for six children 2–4 years of age were performed twice a year. At the age of 2 and 3 years data was obtained by using food recall interviews and at 4 year of age a pre-coded food-diary was used. Results: The energy intake for the 2-year-old children was 3.25 MJ/day (SD 0.85 and for the 3- and 4-year olds 3.62 MJ/day (SD 0.73 and 4.07 MJ/day (SD 0.39 MJ, respectively. These intakes are 61%, 68%, and 77% of the estimated energy requirements in NNR for healthy 2-, 3- and 4-year-old children, respectively, and 60% and 66% of the energy intakes of 2- and 4-year-old children in reference populations. The children's BMI-for-age score and length growth was within the normal range during the study period. The intake of fat was about 25 E% in all age groups and reduced when compared with reference populations. In 25% of the assessments the fat intake was 20 E% or below. The intake of iron was below recommendations in all age groups both with and without supplementation. The mean intake of vitamin D and tocopherol was below recommendations when intakes were determined excluding dietary supplementations. Conclusions: More large-scale investigations on nutritional intake are needed to further investigate dietary challenges for this patient group.

  18. Comparative evaluations of surface contamination detectors calibration with radioactive sources - used in the Goiania accident, and standard sources

    International Nuclear Information System (INIS)

    Becker, P.H.B.; Marecha, M.H.H.

    1997-01-01

    The construction of Cs-137 standard flat sources for calibration of surface contamination detectors, used in the Goiania accident in 1987, is described and the procedures adopted are reported. At that time, standard sources were not available. Nowadays the Instituto de Radioprotecao e Dosimetria has standard sources acquired from Amersham which are used as calibration standards for surface contamination detectors. Comparative evaluations between the standard flat sources constructed for the accident and the calibrated ones are presented

  19. Genetic syndromes in the family : child characteristics and parenting stress in Angelman, CHARGE, Cornelia de Lange, Prader-Willi, and Rett syndrome

    NARCIS (Netherlands)

    Wulffaert, Josette

    2010-01-01

    Aim of the dissertation: To expand the knowledge on the behavioural phenotypes, level of parenting stress and the relationship between child characteristics and parenting stress in five genetic syndromes. The included syndromes are Angelman, CHARGE, Cornelia de Lange, Prader-Willi, and Rett

  20. Short- versus long-term radon detectors: a comparative study in Galicia, NW Spain

    International Nuclear Information System (INIS)

    Ruano-Ravina, A.; Castro-Bernardez, M.; Sande-Meijide, M.; Vargas, A.; Barros-Dios, J.M.

    2008-01-01

    As reported in previous studies, Galicia (NW Spain) is an area of high radon concentrations. This study was sought to analyze the correlation between short-term (activated carbon) and long-term (alpha particle track) detectors in this geographic area, and ascertain whether there were differences in their readings that might be influenced by other variables. A comparison study, as part of a case-control study was designed in which two detectors, one of each type, were placed in the selected homes. A total of 391 homes yielded readings with both detectors. The results indicated that there was a relatively good correlation between both types of monitors (correlation coefficient 0.608; p < 0.001). The highest correlations between both detectors were observed for unventilated homes, coastal sites, and the oldest buildings. Short-term and long-term detectors do not show a similar performance in all settings or situations. It is advisable to use long-term detectors whenever possible

  1. Short- versus long-term radon detectors: a comparative study in Galicia, NW Spain

    Energy Technology Data Exchange (ETDEWEB)

    Ruano-Ravina, A. [Department of Preventive Medicine and Public Health, School of Medicine, University of Santiago de Compostela, C/San Francisco s/n, 15782 Santiago de Compostela (Spain); Galician Agency for Health Technology Assessment, Galician Health Service, Santiago de Compostela (Spain); CIBER de Epidemiologia y Salud Publica, CIBERESP (Spain)], E-mail: mralbert@usc.es; Castro-Bernardez, M. [Epidemiology Department, Directorate-General for Public Health, Galician Regional Authority (Spain); Sande-Meijide, M. [Preventive Medicine Unit, Ourense Hospital Complex, Galician Health Service (Spain); Vargas, A. [Energy Techniques Institute, Polytechnic University of Catalonia, Barcelona (Spain); Barros-Dios, J.M. [Department of Preventive Medicine and Public Health, School of Medicine, University of Santiago de Compostela, C/San Francisco s/n, 15782 Santiago de Compostela (Spain); CIBER de Epidemiologia y Salud Publica, CIBERESP (Spain); Preventive Medicine Unit, Santiago de Compostela University Hospital, Galician Health Service (Spain)

    2008-07-15

    As reported in previous studies, Galicia (NW Spain) is an area of high radon concentrations. This study was sought to analyze the correlation between short-term (activated carbon) and long-term (alpha particle track) detectors in this geographic area, and ascertain whether there were differences in their readings that might be influenced by other variables. A comparison study, as part of a case-control study was designed in which two detectors, one of each type, were placed in the selected homes. A total of 391 homes yielded readings with both detectors. The results indicated that there was a relatively good correlation between both types of monitors (correlation coefficient 0.608; p < 0.001). The highest correlations between both detectors were observed for unventilated homes, coastal sites, and the oldest buildings. Short-term and long-term detectors do not show a similar performance in all settings or situations. It is advisable to use long-term detectors whenever possible.

  2. Influence of Gender and Age on Average Dimensions of Arteries Forming the Circle of Willis Study by Magnetic Resonance Angiography on Kosovo’s Population

    Science.gov (United States)

    Shatri, Jeton; Bexheti, Dorentina; Bexheti, Sadi; Kabashi, Serbeze; Krasniqi, Shaip; Ahmetgjekaj, Ilir; Zhjeqi, Valbona

    2017-01-01

    BACKGROUND: Circulus arteriosus cerebri is the main source of blood supply to the brain; it connects the left and right hemispheres with anterior and posterior parts. Located at the interpenducular fossa at the base of the brain the circle of Willis is the most important source of collateral circulation in the presence of the disease in the carotid or vertebral artery. AIM: The purpose of the research is to study the diameter and length of arteries and provide an important source of reference on Kosovo’s population. METHODS: This is an observative descriptive study performed at the University Clinical Center of Kosovo. A randomised sample of 133 angiographic examinations in adult patients of both sexes who were instructed to exploration is included. RESULTS: The diameters and lengths measured in our study were comparable with other brain-cadaver studies especially those performed by MRA. All dimensions of the arteries are larger in male than female, except the diameter of PCoA that is larger in female (p < 0.05) and length of the ACoA (p < 0.05). Significant differences were found in diameters of arteries between the younger and the older age groups. CONCLUSION: Knowing the dimensions of the arteries of the circle of Willis has a great importance in interventional radiology as well as during anatomy lessons. PMID:29104678

  3. Willie Hobbs Moore (1934-1994): The First Female African American Physicist

    Science.gov (United States)

    Mickens, Ronald

    2011-03-01

    We discuss the life and career of Willie Hobbs Moore, the first African American woman to receive a doctorate degree in physics. This achievement occurred in June 1972 at the University of Michigan, Ann Arbor, MI. Her dissertation, directed by the renowned spectroscopist Samuel Krimm, was on the subject of ``A Vibrational Analysis of Secondary Chlorides," and focused on a theoretical analysis of the secondary chlorides for polyvinal-chlorine polymers. From 1972--1977, she, Krimm, and collaborators published more than thirty papers on this and related research issues. In addition to an overview of her family background, her careers as a research physicist and scientist working in various industrial laboratories, we discuss the obstacles and successes she encountered at various stages of her life.

  4. Cognitive and behavioural aspects of Prader-Willi syndrome.

    Science.gov (United States)

    Rice, Lauren J; Einfeld, Stewart L

    2015-03-01

    To provide a review of the recent advances in the diagnosis and treatment of psychiatric disorders in Prader-Willi syndrome (PWS). Research in the last 12 months has provided a descriptive prognosis of psychosis in PWS and highlighted the possible genes associated with the increased risk of psychosis for those with maternal uniparental disomy (mUPD). Several studies investigating social and communication skills have shown people with PWS to have difficulty with core, receptive and expressive language skills, interpreting emotional valence in faces, playing with children of their own age, understanding personal space and a developmental delay in the theory of mind. These social and communication deficits are often more pronounced in those with mUPD. Two recent clinical trials of oxytocin provide mixed results and highlight the need for an improved understanding of the neurobiological characteristics of the PWS brain. A recent pilot study suggests N-acetylcysteine may be a viable treatment for skin picking. Recent advances have contributed to our understanding of the emotional and behavioural problems associated with PWS, and provided directions for further research.

  5. Bone mineral density and effects of growth hormone treatment in prepubertal children with Prader-Willi syndrome: a randomized controlled trial.

    NARCIS (Netherlands)

    Lind van Wijngaarden, R.F. de; Festen, D.A.M.; Otten, B.J.; Mil, E.G. van; Rotteveel, J.J.; Odink, R.J.; Leeuwen, M. van; Haring, D.A.; Bocca, G.; Mieke Houdijk, E.C.; Hokken-Koelega, A.C.S.

    2009-01-01

    BACKGROUND: Bone mineral density (BMD) is unknown in children with Prader-Willi syndrome (PWS), but is decreased in adults with PWS. In patients with GH deficiency, BMD increases during GH treatment. OBJECTIVES: The aim of the study was to evaluate BMD in children with PWS and to study the effects

  6. Bone Mineral Density and Effects of Growth Hormone Treatment in Prepubertal Children with Prader-Willi Syndrome : A Randomized Controlled Trial

    NARCIS (Netherlands)

    van Wijngaarden, Roderick F. A. de Lind; Festen, Dederieke A. M.; Otten, Barto J.; van Mil, Edgar G. A. H.; Rotteveel, Joost; Odink, Roelof J.; van Leeuwen, Mariette; Haring, Danny A. J. P.; Bocca, Gianni; Houdijk, E. C. A. Mieke; Hokken-Koelega, Anita C. S.

    2009-01-01

    Background: Bone mineral density (BMD) is unknown in children with Prader-Willi syndrome (PWS), but is decreased in adults with PWS. In patients with GH deficiency, BMD increases during GH treatment. Objectives: The aim of the study was to evaluate BMD in children with PWS and to study the effects

  7. Relationship between the IQ of People with Prader-Willi Syndrome and that of Their Siblings: Evidence for Imprinted Gene Effects

    Science.gov (United States)

    Whittington, J.; Holland, A.; Webb, T.

    2009-01-01

    Background: Genetic disorders occasionally provide the means to uncover potential mechanisms linking gene expression and physical or cognitive characteristics or behaviour. Prader-Willi syndrome (PWS) is one such genetic disorder in which differences between the two main genetic subtypes have been documented (e.g. higher verbal IQ in one vs.…

  8. Detector to detector corrections: a comprehensive experimental study of detector specific correction factors for beam output measurements for small radiotherapy beams

    DEFF Research Database (Denmark)

    Azangwe, Godfrey; Grochowska, Paulina; Georg, Dietmar

    2014-01-01

    -doped aluminium oxide (Al2O3:C), organic plastic scintillators, diamond detectors, liquid filled ion chamber, and a range of small volume air filled ionization chambers (volumes ranging from 0.002 cm3 to 0.3 cm3). All detector measurements were corrected for volume averaging effect and compared with dose ratios...... measurements, the authors recommend the use of detectors that require relatively little correction, such as unshielded diodes, diamond detectors or microchambers, and solid state detectors such as alanine, TLD, Al2O3:C, or scintillators....

  9. Psychotropic treatments in Prader-Willi syndrome: a critical review of published literature.

    Science.gov (United States)

    Bonnot, O; Cohen, D; Thuilleaux, D; Consoli, A; Cabal, S; Tauber, M

    2016-01-01

    Prader-Willi syndrome (PWS) is a rare genetic syndrome. The phenotype includes moderate to intellectual disability, dysmorphia, obesity, and behavioral disturbances (e.g., hetero and self-injurious behaviors, hyperphagia, psychosis). Psychotropic medications are widely prescribed in PWS for symptomatic control. We conducted a systematic review of published literature to examine psychotropic medications used in PWS. MEDLINE was searched to identify articles published between January 1967 and December 2014 using key words related to pharmacological treatments and PWS. Articles with original data were included based on a standardized four-step selection process. The identification of studies led to 241 records. All selected articles were evaluated for case descriptions (PWS and behavioral signs) and treatment (type, titration, efficiency, and side effects). Overall, 102 patients were included in these studies. Treatment involved risperidone (three reports, n = 11 patients), fluoxetine (five/n = 6), naltrexone (two/n = 2), topiramate (two/n = 16), fluvoxamine (one/n = 1), mazindol (one/n = 2), N-acetyl cysteine (one/n = 35), rimonabant (one/n = 15), and fenfluramine (one/n = 15). We identified promising treatment effects with topiramate for self-injury and impulsive/aggressive behaviors, risperidone for psychotic symptoms associated with uniparental disomy (UPD), and N-acetyl cysteine for skin picking. The pharmacological approach of behavioral impairment in PWS has been poorly investigated to date. Further randomized controlled studies are warranted. Behavioral disturbances in Prader-Willi syndrome including aggressive reactions, skin picking, and hyperphagia might be very difficult to manage. Antipsychotic drugs are widely prescribed, but weight gain and increased appetite are their major side effects. Topiramate might be efficient for self-injury and impulsive/aggressive behaviors, N-acetyl cysteine is apromising treatment for

  10. Motor performance in Prader-Willi syndrome patients and its potential influence on caregiver’s quality of life

    OpenAIRE

    Valeria Jia-Yi Chiu; Li-Ping Tsai; Jang-Ting Wei; I-Shiang Tzeng; Hsin-Chi Wu

    2017-01-01

    Background Prader-Willi syndrome (PWS) is a complex, multisystem genetic disorder characterized by a variety of physical, cognitive, and behavioral impairments. PWS is a unique sarcopenia model characterized by an abnormal increase in body fat mass and a decrease in muscle mass that predisposes patients to reduced physical activity, functional limitations, and disability. These manifestations may require both symptomatic and supportive management, thus negatively influencing their lifelong fa...

  11. Beneficial effects of growth hormone treatment on cognition in children with prader-willi syndrome: A randomized controlled trial and longitudinal study

    NARCIS (Netherlands)

    E.P.C. Siemensma (Elbrich); R.F.A. Tummers-de Lind Van Wijngaarden (Roderick F.); D.A.M. Festen (Dederieke); Z.C.E. Troeman (Zyrhea C.); A.A.E.M. van der Alfen-van Der Velden; B.J. Otten (Barto); J. Rotteveel (Joost); R.J.H. Odink (Roelof); G.C.B. Bindels-de Heus (Karen); M. van Leeuwen (Mariëtte); D.A.J.P. Haring (Danny); W. Oostdijk (Wilma); G. Bocca (Gianni); E.C.A.M. Houdijk (Mieke); A.S.P. van Trotsenburg (Paul); J.J.G. Hoorweg-Nijman (Gera); H. van Wieringen (Hester); R.C.F.M. Vreuls (René); P.E. Jira (Petr); E.J. Schroor (Eelco); E. van Pinxteren-Nagler (Evelyn); J.W. Pilon; S. Lunshof (Simone); A.C.S. Hokken-Koelega (Anita)

    2012-01-01

    textabstractBackground: Knowledge about the effects of GH treatment on cognitive functioning in children with Prader-Willi syndrome (PWS) is limited. Methods: Fifty prepubertal children aged 3.5 to 14 yr were studied in a randomized controlled GH trial during 2 yr, followed by a longitudinal study

  12. Prader-Willi Syndrome: A Case Study and Parent Perspective.

    Science.gov (United States)

    Glaspy, Erin; Foge, Julie

    2015-08-01

    Having a newborn diagnosed with a rare disorder is fraught with many challenges and opportunities for families and healthcare providers alike. This article presents one mother's journey through the daily blessings and challenges of having a child with a rare disorder. Storytelling and reflection interwoven with a case presentation. Prader-Willi syndrome can be a diagnosis that is missed in the immediate postpartum period. Careful assessment and evaluation of the infant is needed. Attention to detail will support an accurate and timely diagnosis. Those involved in the care of infants in the neonatal intensive care unit with special needs owing to a rare disorder must guide families through the difficult process of establishing a diagnosis and coping with the short- and long-term implications of that diagnosis. Research about the needs of families with children with rare diseases is sorely needed. Finding strategies to best support these families is an area of great need.

  13. Cardiovascular and metabolic risk profile and acylation-stimulating protein levels in children with Prader-Willi syndrome and effects of growth hormone treatment

    NARCIS (Netherlands)

    R.F.A. de Lind van Wijngaarden (Roderick); K. Cianflone (Katherine); Y. Gao; R.W.J. Leunissen (Ralph); A.C.S. Hokken-Koelega (Anita)

    2010-01-01

    textabstractContext: Reports on the cardiovascular and metabolic risk profile in children with Prader-Willi syndrome (PWS) and the effects of GH treatment are scarce. Acylation-stimulating protein (ASP) stimulates glucose uptake and triglyceride storage in adipose tissue. Objectives: The aim was to

  14. The developmental trajectory of disruptive behavior in Down syndrome, fragile X syndrome, Prader-Willi syndrome and Williams syndrome.

    Science.gov (United States)

    Rice, Lauren J; Gray, Kylie M; Howlin, Patricia; Taffe, John; Tonge, Bruce J; Einfeld, Stewart L

    2015-06-01

    The aim of this study was to investigate the developmental trajectories of verbal aggression, physical aggression, and temper tantrums in four genetic syndrome groups. Participants were part of the Australian Child to Adult Development Study (ACAD), which collected information from a cohort of individuals with an intellectual disability at five time points over 18 years. Data were examined from a total of 248 people with one of the four following syndromes: Down syndrome, Fragile X syndrome, Prader-Willi syndrome, or Williams syndrome. Changes in behaviors were measured using validated items from the Developmental Behavior Checklist (DBC). The results indicate that, while verbal aggression shows no evidence of diminishing with age, physical aggression, and temper tantrums decline with age before 19 years for people with Down syndrome, Fragile X syndrome, and William syndrome; and after 19 years for people with Prader-Willi syndrome. These findings offer a somewhat more optimistic outlook for people with an intellectual disability than has previously been suggested. Research is needed to investigate the mechanisms predisposing people with PWS to persistence of temper tantrums and physical aggression into adulthood. © 2015 Wiley Periodicals, Inc.

  15. Diagnosis and treatments of Prader-Willi syndrome: a review of current consensuses

    Directory of Open Access Journals (Sweden)

    2014-05-01

    Full Text Available We analyzed international consensuses of experts and clinical recommendations on diagnosis and treatment of Prader-Willi syndrome (PWS: PWS consensus diagnostic criteria (1993; US PWS Association (PWSA-USA consensus statements on evaluating of breathing abnormalities (2007, osteoporosis (2008, growth hormone treatment in PWS (2000 and 2009; Endocrine society clinical practice guideline on Prevention and treatment of pediatric obesity (2008; the Second Expert Meeting of the Comprehensive Care of Patients with PWS Consensus published as Recommendations for the diagnosis and management of PWS (2008. Historical analysis and comparison of recommendations are presented in this review article. Absence of Russian clinical practice guidelines on PWS patients management makes necessary the detailed study of listed documents.

  16. Upconversion detector for methane atmospheric sensor

    DEFF Research Database (Denmark)

    Meng, Lichun; Fix, Andreas; Høgstedt, Lasse

    2017-01-01

    We demonstrate an efficient upconversion detector (UCD) for a methane (CH4) atmospheric sensor. The UCD shows comparable performance with a conventional detector when measuring the backscattered signal from the hard target located 2.3 km away.......We demonstrate an efficient upconversion detector (UCD) for a methane (CH4) atmospheric sensor. The UCD shows comparable performance with a conventional detector when measuring the backscattered signal from the hard target located 2.3 km away....

  17. Beneficial Effects of Growth Hormone Treatment on Cognition in Children with Prader-Willi Syndrome : A Randomized Controlled Trial and Longitudinal Study

    NARCIS (Netherlands)

    Siemensma, Elbrich P. C.; van Wijngaarden, Roderick F. A. Tummers-de Lind; Festen, Dederieke A. M.; Troeman, Zyrhea C. E.; van Alfen-van der Velden, A. A. E. M. (Janielle); Otten, Barto J.; Rotteveel, Joost; Odink, Roelof J. H.; Bindels-de Heus, G. C. B. (Karen); van Leeuwen, Mariette; Haring, Danny A. J. P.; Oostdijk, Wilma; Bocca, Gianni; Houdijk, E. C. A. Mieke; van Trotsenburg, A. S. Paul; Hoorweg-Nijman, J. J. Gera; van Wieringen, Hester; Vreuls, Rene C. F. M.; Jira, Petr E.; Schroor, Eelco J.; van Pinxteren-Nagler, Evelyn; Pilon, Jan Willem; Lunshof, L. (Bert); Hokken-Koelega, Anita C. S.

    Background: Knowledge about the effects of GH treatment on cognitive functioning in children with Prader-Willi syndrome (PWS) is limited. Methods: Fifty prepubertal children aged 3.5 to 14 yr were studied in a randomized controlled GH trial during 2 yr, followed by a longitudinal study during 4 yr

  18. Beneficial effects of growth hormone treatment on cognition in children with Prader-Willi syndrome: a randomized controlled trial and longitudinal study.

    NARCIS (Netherlands)

    Siemensma, E.P.C.; Tummers-de Lind van Wijngaarden, R.F.; Festen, D.A.M.; Troeman, Z.C.; Alfen-van der Velden, A.A.E.M. van; Otten, B.J.; Rotteveel, J.J.; Odink, R.J.; Bindels-de Heus, G.C.; Leeuwen, M. van; Haring, D.A.; Oostdijk, W.; Bocca, G.; Mieke Houdijk, E.C.; Trotsenburg, A.S. van; Hoorweg-Nijman, J.J.G.; Wieringen, H. van; Vreuls, R.C.; Jira, P.E.; Schroor, E.J.; Pinxteren-Nagler, E. van; Willem Pilon, J.; Lunshof, L.B.; Hokken-Koelega, A.C.S.

    2012-01-01

    BACKGROUND: Knowledge about the effects of GH treatment on cognitive functioning in children with Prader-Willi syndrome (PWS) is limited. METHODS: Fifty prepubertal children aged 3.5 to 14 yr were studied in a randomized controlled GH trial during 2 yr, followed by a longitudinal study during 4 yr

  19. Beneficial Effects of Growth Hormone Treatment on Cognition in Children with Prader-Willi Syndrome: A Randomized Controlled Trial and Longitudinal Study

    NARCIS (Netherlands)

    Siemensma, Elbrich P. C.; Tummers-de Lind van Wijngaarden, Roderick F. A.; Festen, Dederieke A. M.; Troeman, Zyrhea C. E.; van Alfen-van der Velden, A. A. E. M. Janielle; Otten, Barto J.; Rotteveel, Joost; Odink, Roelof J. H.; Bindels-de Heus, G. C. B. Karen; van Leeuwen, Mariette; Haring, Danny A. J. P.; Oostdijk, Wilma; Bocca, Gianni; Mieke Houdijk, E. C. A.; van Trotsenburg, A. S. Paul; Hoorweg-Nijman, J. J. Gera; van Wieringen, Hester; Vreuls, René C. F. M.; Jira, Petr E.; Schroor, Eelco J.; van Pinxteren-Nagler, Evelyn; Willem Pilon, Jan; Lunshof, L. Bert; Hokken-Koelega, Anita C. S.

    2012-01-01

    Background: Knowledge about the effects of GH treatment on cognitive functioning in children with Prader-Willi syndrome (PWS) is limited. Methods: Fifty prepubertal children aged 3.5 to 14 yr were studied in a randomized controlled GH trial during 2 yr, followed by a longitudinal study during 4 yr

  20. {sup 3}He Replacement for Nuclear Safeguards Applications- an integrated test program to compare alternative neutron detectors

    Energy Technology Data Exchange (ETDEWEB)

    Menlove, H. O.; Henzlova, D.; Evans, L. G.; Swinhoe, M. T.; Marlow, J. B. [Los Alamos National Laboratory, Safeguards Science and Technology Group, Los Alamos, (United States)

    2011-12-15

    During the past several years, the demand for {sup 3}He gas has far exceeded the gas supply. This shortage of {sup 3}He gas is projected to continue into the foreseeable future. There is a need for alternative neutron detectors that do not require {sup 3}He gas. For more than four decades, neutron detection has played a fundamental role in the safeguarding and control of nuclear materials at production facilities, fabrication plants and storage sites worldwide. Neutron measurements for safeguards applications have requirements that are unique to the quantitative assay of special nuclear materials. These neutron systems measure the neutron multiplicity distributions from each spontaneous fission and/or induced fission event. The neutron time correlation counting requires that two or more neutrons from a single fission event be detected. The doubles and triples neutron counting rate depends on the detector efficiency to the 2nd and 3rd power, respectively, so low efficiency systems will not work for the coincidence measurements, and any detector instabilities are greatly amplified. In the current test program, we will measure the alternative detector properties including efficiency, die-away time, multiplicity precision, gamma sensitivity, dead-time, and we will also consider the detector properties that would allow commercial production to safeguards scale assay systems. This last step needs to be accomplished before the proposed technologies can reduce the demand on {sup 3}He gas in the safeguards world. This paper will present the methodology that includes MCNPX simulations for comparing divergent detector types such as {sup 10}B lined proportional counters with {sup 3}He gas based systems where the performance metrics focus on safeguards applications.

  1. Treino parental para manejo comportamental de crianças com Síndrome de Prader-Willi: impacto sobre a saúde mental e práticas educativas do cuidador

    OpenAIRE

    Mesquita, Maria Luiza Guedes de; Suriano, Raquel; Carreiro, Luiz Renato Rodrigues; Teixeira, Maria Cristina Triguero Veloz

    2016-01-01

    RESUMO Objetivo: verificamos os indicadores de impacto na saúde mental de cuidadores de um programa de treinamento parental para manejo de crianças e adolescentes com Síndrome de Prader-Willi. Métodos: a amostra foi composta por 5 mães de crianças/adolescentes com Síndrome de Prader-Willi entre 6 a 18 anos. Os instrumentos de coleta de dados foram: a) Questionário para verificação de conhecimentos das mães sobre a síndrome, b) Inventário de Auto-avaliação para Adultos de 18 a 59 anos, c) In...

  2. Comparative analysis for the measured and the predicted relative sensitivity of rhodium In core detector

    International Nuclear Information System (INIS)

    Moon, Sang Rae; Cha, Kyoon Ho; Bae, Seong Man

    2012-01-01

    Self-powered neutron detector (SPND) is widely used as in-core flux monitoring in nuclear power plants. OPR1000 has applied a rhodium (Rh) as the emitter of the SPND. The SPND contains a neutron-sensitive metallic emitter surrounded by a ceramic insulator. When capturing a neutron, the Rh will be decayed by emitting some electrons which is crossing the sheath and produce current. This current can be measured externally using pico-ammeter. The sensitivity of detectors is closely related with the geometry and material of the detectors. The lifetime of in-core detector is determined by calculating the relative sensitivity of Rh detector. It is required that the Rh detector should be replaced before the burn-up of Rh detector has reached 66% of its original compositions. To predict Rh detector's relative sensitivity ANC code, advanced nodal code capable of two-dimensional and three-dimensional calculations, is used. It is determined that the Rh detectors should be replaced on the basis of the predicted sensitivity value calculated by ANC code. When evaluating the life of Rh detectors using ANC code, it is assumed that the uncertainty of the sensitivity calculation include the measurement error of 5%. As a result of the analysis of measured and predicted data for the Rh detector's relative sensitivity, it is possible to reduce the assumed uncertainty

  3. Comparative analysis for the measured and the predicted relative sensitivity of rhodium In core detector

    Energy Technology Data Exchange (ETDEWEB)

    Moon, Sang Rae; Cha, Kyoon Ho; Bae, Seong Man [Nuclear Reactor Safety Lab., KHNP Central Research Institute, Daejeon (Korea, Republic of)

    2012-10-15

    Self-powered neutron detector (SPND) is widely used as in-core flux monitoring in nuclear power plants. OPR1000 has applied a rhodium (Rh) as the emitter of the SPND. The SPND contains a neutron-sensitive metallic emitter surrounded by a ceramic insulator. When capturing a neutron, the Rh will be decayed by emitting some electrons which is crossing the sheath and produce current. This current can be measured externally using pico-ammeter. The sensitivity of detectors is closely related with the geometry and material of the detectors. The lifetime of in-core detector is determined by calculating the relative sensitivity of Rh detector. It is required that the Rh detector should be replaced before the burn-up of Rh detector has reached 66% of its original compositions. To predict Rh detector's relative sensitivity ANC code, advanced nodal code capable of two-dimensional and three-dimensional calculations, is used. It is determined that the Rh detectors should be replaced on the basis of the predicted sensitivity value calculated by ANC code. When evaluating the life of Rh detectors using ANC code, it is assumed that the uncertainty of the sensitivity calculation include the measurement error of 5%. As a result of the analysis of measured and predicted data for the Rh detector's relative sensitivity, it is possible to reduce the assumed uncertainty.

  4. Effect of cessation of GH treatment on cognition during transition phase in Prader-Willi syndrome: Results of a 2-year crossover GH trial

    NARCIS (Netherlands)

    R.J. Kuppens (Renske); Mahabier, E.F.; N.E. Bakker (Nienke); E.P.C. Siemensma (Elbrich); S.H. Donze (Stephanie); A.C.S. Hokken-Koelega (Anita)

    2016-01-01

    textabstractBackground: Patients with Prader-Willi syndrome (PWS) have a cognitive impairment. Growth hormone (GH) treatment during childhood improves cognitive functioning, while cognition deteriorates in GH-untreated children with PWS. Cessation of GH treatment at attainment of adult height (AH)

  5. Undepleted silicon detectors

    International Nuclear Information System (INIS)

    Rancoita, P.G.; Seidman, A.

    1985-01-01

    Large-size silicon detectors employing relatively low resistivity material can be used in electromagnetic calorimetry. They can operate in strong magnetic fields, under geometric constraints and with microstrip detectors a high resolution can be achieved. Low noise large capacitance oriented electronics was developed to enable good signal-to-noise ratio for single relativistic particles traversing large area detectors. In undepleted silicon detectors, the charge migration from the field-free region has been investigated by comparing the expected peak position (from the depleted layer only) of the energy-loss of relativistic electrons with the measured one. Furthermore, the undepleted detectors have been employed in a prototype of Si/W electromagnetic colorimeter. The sensitive layer was found to be systematically larger than the depleted one

  6. The European Prader-Willi Syndrome Clinical Research Database: An Aid in the Investigation of a Rare Genetically Determined Neurodevelopmental Disorder

    Science.gov (United States)

    Holland, A.; Whittington, J.; Cohen, O.; Curfs, L.; Delahaye, F.; Dudley, O.; Horsthemke, B.; Lindgren, A. -C.; Nourissier, C.; Sharma, N.; Vogels, A.

    2009-01-01

    Background: Prader-Willi Syndrome (PWS) is a rare genetically determined neurodevelopmental disorder with a complex phenotype that changes with age. The rarity of the syndrome and the need to control for different variables such as genetic sub-type, age and gender limits clinical studies of sufficient size in any one country. A clinical research…

  7. Mechanisms of obesity in Prader-Willi syndrome.

    Science.gov (United States)

    Khan, M J; Gerasimidis, K; Edwards, C A; Shaikh, M G

    2018-01-01

    Obesity is the most common cause of metabolic complications and poor quality of life in Prader-Willi syndrome (PWS). Hyperphagia and obesity develop after an initial phase of poor feeding and failure to thrive. Several mechanisms for the aetiology of obesity in PWS are proposed, which include disruption in hypothalamic pathways of satiety control resulting in hyperphagia, aberration in hormones regulating food intake, reduced energy expenditure because of hypotonia and altered behaviour with features of autism spectrum disorder. Profound muscular hypotonia prevents PWS patients from becoming physically active, causing reduced muscle movements and hence reduced energy expenditure. In a quest for the aetiology of obesity, recent evidence has focused on several appetite-regulating hormones, growth hormone, thyroid hormones and plasma adipocytokines. However, despite advancement in understanding of the genetic basis of PWS, there are contradictory data on the role of satiety hormones in hyperphagia and data regarding dietary intake are limited. Mechanistic studies on the aetiology of obesity and its relationship with disease pathogenesis in PWS are required. . In this review, we focused on the available evidence regarding mechanisms of obesity and potential new areas that could be explored to help unravel obesity pathogenesis in PWS. © 2016 World Obesity Federation.

  8. Stress, Locus of Control, and Family Cohesion and Adaptability in Parents of Children with Down, Williams, Fragile X, and Prader-Willi Syndromes

    Science.gov (United States)

    Lanfranchi, Silvia; Vianello, Renzo

    2012-01-01

    The present study analyzes differences in parental stress in families of children with Down, Williams, Fragile X, and Prader-Willi syndromes, exploring factors that influence parental stress, such as child's characteristics, parental locus of control, and family cohesion and adaptability. Differences between mothers and fathers are also…

  9. Scatter Plot Analysis of Excessive Daytime Sleepiness and Severe Disruptive Behavior in Adults with Prader-Willi Syndrome: A Pilot Study

    Science.gov (United States)

    Maas, Anneke P. H. M.; Didden, Robert; Bouts, Lex; Smits, Marcel G.; Curfs, Leopold M. G.

    2009-01-01

    Individuals with Prader-Willi syndrome (PWS) are at risk for excessive daytime sleepiness (EDS) and disruptive behavior. This pilot study explores temporal characteristics of EDS and severe disruptive behavior across time of day and day of week in seven individuals with PWS (aged between 33 and 49 years) of whom five were matched to controls.…

  10. Grey matter volume and cortical structure in Prader-Willi syndrome compared to typically developing young adults

    Directory of Open Access Journals (Sweden)

    Katherine E. Manning

    2018-01-01

    Full Text Available Prader-Willi syndrome (PWS is a neurodevelopmental disorder of genomic imprinting, presenting with a characteristic overeating disorder, mild to moderate intellectual disability, and a variable range of social and behavioral difficulties. Consequently, widespread alterations in neural structure and developmental and maturational trajectory would be expected. To date, there have been few quantitative and systematic studies of brain morphology in PWS, although alterations of volume and of cortical organisation have been reported. This study aimed to investigate, in detail, the structure of grey matter and cortex in the brain in a sample of young adults with PWS in a well-matched case-controlled analysis. 20 young adults with PWS, aged 19–27 years, underwent multiparameter mapping magnetic resonance imaging sequences, from which measures of grey matter volume, cortical thickness and magnetisation transfer saturation, as a proxy measure of myelination, were examined. These variables were investigated in comparison to a control group of 40 typically developing young adults, matched for age and sex. A voxel-based morphometry analysis identified large and widespread bilateral clusters of both increased and decreased grey matter volume in the brain in PWS. In particular, widespread areas of increased volume encompassed parts of the prefrontal cortex, especially medially, the majority of the cingulate cortices, from anterior to posterior aspects, insula cortices, and areas of the parietal and temporal cortices. Increased volume was also reported in the caudate, putamen and thalamus. The most ventromedial prefrontal areas, in contrast, showed reduced volume, as did the parts of the medial temporal lobe, bilateral temporal poles, and a small cluster in the right lateral prefrontal cortex. Analysis of cortical structure revealed that areas of increased volume in the PWS group were largely driven by greater cortical thickness. Conversely, analysis of

  11. Grey matter volume and cortical structure in Prader-Willi syndrome compared to typically developing young adults.

    Science.gov (United States)

    Manning, Katherine E; Tait, Roger; Suckling, John; Holland, Anthony J

    2018-01-01

    Prader-Willi syndrome (PWS) is a neurodevelopmental disorder of genomic imprinting, presenting with a characteristic overeating disorder, mild to moderate intellectual disability, and a variable range of social and behavioral difficulties. Consequently, widespread alterations in neural structure and developmental and maturational trajectory would be expected. To date, there have been few quantitative and systematic studies of brain morphology in PWS, although alterations of volume and of cortical organisation have been reported. This study aimed to investigate, in detail, the structure of grey matter and cortex in the brain in a sample of young adults with PWS in a well-matched case-controlled analysis. 20 young adults with PWS, aged 19-27 years, underwent multiparameter mapping magnetic resonance imaging sequences, from which measures of grey matter volume, cortical thickness and magnetisation transfer saturation, as a proxy measure of myelination, were examined. These variables were investigated in comparison to a control group of 40 typically developing young adults, matched for age and sex. A voxel-based morphometry analysis identified large and widespread bilateral clusters of both increased and decreased grey matter volume in the brain in PWS. In particular, widespread areas of increased volume encompassed parts of the prefrontal cortex, especially medially, the majority of the cingulate cortices, from anterior to posterior aspects, insula cortices, and areas of the parietal and temporal cortices. Increased volume was also reported in the caudate, putamen and thalamus. The most ventromedial prefrontal areas, in contrast, showed reduced volume, as did the parts of the medial temporal lobe, bilateral temporal poles, and a small cluster in the right lateral prefrontal cortex. Analysis of cortical structure revealed that areas of increased volume in the PWS group were largely driven by greater cortical thickness. Conversely, analysis of myelin content using

  12. Le sens de l’écart : la narration déconstruite dans les vidéos de Willie Doherty

    Directory of Open Access Journals (Sweden)

    Valérie Morisson

    2011-08-01

    Full Text Available Dans les œuvres vidéographiques de l’artiste nord-irlandais Willie Doherty, les éléments narratifs entretiennent une relation complexe avec les images filmiques. Témoin de la guerre civile, récepteur méfiant des images du conflit, Doherty n’a de cesse de rappeler que la mémoire individuelle du traumatisme est erratique et le statut de victime problématique. La déconstruction du récit, l’instabilité de la focalisation, ainsi que l’écart, voire l’incompatibilité, entre l’image et le texte qui l’accompagne aboutissent à une réflexion sur les dissensions historiques. La voix off devient alors un facteur d’incertitude.In his video works, all tightly focused on the Northern-Irish conflict, Willie Doherty probes the perpetrator-victim dyad and denounces the truncated visual representation of the conflict by deconstructing the relation between image and sound. The texts uttered by the voice-over raise political issues relevant to post-conflict Ireland, whether it be victimhood, national trauma or the construction of collective memory. Multiple open-ended interwoven narratives accompany images without closing their interpretation.

  13. Near demise of a child with Prader-Willi syndrome during elective orchidopexy.

    Science.gov (United States)

    Mantadakis, Elpis; Spanaki, Anna-Maria; Geromarkaki, Elsa; Vassilaki, Efrosini; Briassoulis, George

    2006-07-01

    The case of a morbidly obese 3.5-year-old boy, with Prader-Willi syndrome (PWS), who experienced a life-threatening episode of pulmonary edema soon after induction of general anesthesia with sevoflurane and intubation for orchidopexy is presented. The patient who had history of sleep apnea and who had an uneventful laparoscopy under general anesthesia 6 months previously was supported with mechanical ventilation with positive end expiratory pressure but developed hyperthermia, pneumonia, sepsis, and Acute Respiratory Distress Syndrome in the intensive care unit. He recovered fully 11 days after surgery. The possible contributing factors for the development of pulmonary edema are discussed. Arrangements for monitoring in an intensive care setting after surgery are highly recommended for patients with PWS.

  14. Smile detectors correlation

    Science.gov (United States)

    Yuksel, Kivanc; Chang, Xin; Skarbek, Władysław

    2017-08-01

    The novel smile recognition algorithm is presented based on extraction of 68 facial salient points (fp68) using the ensemble of regression trees. The smile detector exploits the Support Vector Machine linear model. It is trained with few hundreds exemplar images by SVM algorithm working in 136 dimensional space. It is shown by the strict statistical data analysis that such geometric detector strongly depends on the geometry of mouth opening area, measured by triangulation of outer lip contour. To this goal two Bayesian detectors were developed and compared with SVM detector. The first uses the mouth area in 2D image, while the second refers to the mouth area in 3D animated face model. The 3D modeling is based on Candide-3 model and it is performed in real time along with three smile detectors and statistics estimators. The mouth area/Bayesian detectors exhibit high correlation with fp68/SVM detector in a range [0:8; 1:0], depending mainly on light conditions and individual features with advantage of 3D technique, especially in hard light conditions.

  15. Calibration comparative results for X - and gamma ray spectrometry with HPGe and BEGe detectors for a radon reference chamber

    International Nuclear Information System (INIS)

    Zoran, Maria; Paul, Annette; Arnold, Dirk

    2002-01-01

    Inhaled decay products of 222 Rn are the dominant components of the natural radiation exposure being responsible for about 30% of the whole human radioactive exposure. Field instruments for 222 Rn and his progeny monitoring are calibrated in 'radon climate rooms', where it is possible to vary and monitor 222 Rn and the indoor air parameters ( temperature, humidity, ventilation rate, aerosol concentration). German radon reference chamber used was developed and installed at the Physikalisch-Technische Bundesanstalt in order to serve as a metrological standard for radon and his progeny calibration of active and passive, indoor and outdoor radon monitoring devices in air climate. The basic parts of experimental setup for this γ and X -ray spectrometry analysis consists of a γ-X ray source in a lead shield/collimator, the detectors, the electronics necessary for pulse-height analysis (PHA) to obtain energy spectra. For calibrating system with 226 Ra standard sources (multienergy X ray and gamma emitters), two germanium detectors HPGe (12.5 nominal efficiency) and BEGe (22.5 nominal efficiency) were used. Germanium detectors are semiconductor diodes having a P-I-N structure in which the Intrinsic (I) region is sensitive to ionizing radiation, particularly X-rays and gamma rays. The BEGe is designed with an electrode structure that enhances low energy resolution and is fabricated from selected germanium having an impurity profile that improves charge collection (thus resolution and peak shape) at high energies which is really important in analysis of the complex spectra for uranium and finally for 226 Ra. MAESTRO MCA software and GNUPLOT program were used for spectra acquisition and spectra analysis, respectively . The main aim of this paper was to do a comparatively analysis of the detector performances for this radon chamber spectrometric chain. The calibration data analysis includes energy calibrations for both detection systems as well as comparative X and gamma

  16. Hypothalamic growth hormone-releasing hormone (GHRH) cell number is increased in human illness, but is not reduced in Prader-Willi syndrome or obesity

    NARCIS (Netherlands)

    Goldstone, Anthony P.; Unmehopa, Unga A.; Swaab, Dick F.

    2003-01-01

    Acute illness leads to increased GH, but reduced IGF-I secretion, while both are reduced in chronic illness. Prader-Willi syndrome (PWS) is a genetic obesity syndrome, with GH deficiency a feature independent of obesity. Reduced GH secretion may result from decreased hypothalamic release of

  17. Gait patterns in Prader-Willi and Down syndrome patients

    Directory of Open Access Journals (Sweden)

    Albertini Giorgio

    2010-06-01

    Full Text Available Abstract Background Prader-Willi (PWS and Down Syndrome (DS are two genetic disorders characterised by some common clinical and functional features. A quantitative description and comparison of their patterns would contribute to a deeper understanding of the determinants of motor disability in these two syndromes. The aim of this study was to measure gait pattern in PWS and DS in order to provide data for developing evidence-based deficit-specific or common rehabilitation strategies. Methods 19 PWS patients (17.7-40 yr and 21 DS patients (18-39 yr were evaluated with an optoelectronic system and force platforms for measuring kinematic and kinetic parameters during walking. The results were compared with those obtained in a group of normal-weight controls (Control Group: CG; 33.4 + 9.6 yr. Results and Discussion The results show that PWS and DS are characterised by different gait strategies. Spatio-temporal parameters indicated a cautious, abnormal gait in both groups, but DS walked with a less stable strategy than PWS. As for kinematics, DS showed a significantly reduced hip and knee flexion, especially at initial contact and ankle range of motion than PWS. DS were characterised by lower ranges of motion (p Conclusions Our data show that DS walk with a less physiological gait pattern than PWS. Based on our results, PWS and DS patients need targeted rehabilitation and exercise prescription. Common to both groups is the aim to improve hypotonia, muscle strength and motor control during gait. In DS, improving pelvis and hip range of motion should represent a major specific goal to optimize gait pattern.

  18. Energy Expenditure and Physical Activity in Prader–Willi Syndrome

    Science.gov (United States)

    Butler, Merlin G.; Theodoro, Mariana F.; Bittel, Douglas C.; Donnelly, Joseph E.

    2017-01-01

    Prader–Willi syndrome (PWS) is a complex neurodevelopmental disorder characterized by hypotonia, suck and feeding difficulties, hypogonadism, small hands and feet, developmental delay, hyperphagia and early childhood obesity and a particular facial appearance. The obesity associated with PWS is the result of a chronic imbalance between energy intake and energy expenditure (EE) due to hyperphagia, decreased physical activity, reduced metabolic rate and an inability to vomit. EE is affected by body composition as well as exercise. Individuals with PWS have a lower lean body mass (LBM) compared with controls which may contribute to reduced basal level EE. To determine the relationship among body composition, activity levels and metabolic rates, dual energy X-ray absorptiometry (DEXA) and a whole-room respiration chamber were used to measure body composition, total EE (TEE), resting EE (REE), physical activity, and mechanical work (MW) during an 8 hr monitoring period. The chamber consisted of a live-in whole-room indirect calorimeter equipped with a force platform floor to allow simultaneous measurement of EE, physical activity, and work efficiency during spontaneous activities and standardized exercise. Participants with PWS (27 with 15q11–q13 deletion and 21 with maternal disomy 15 with an average age of 23 years) had significantly decreased TEE by 20% and reduced LBM compared to 24 obese subjects. Similarly, REE was significantly reduced by 16% in the individuals with PWS relative to the comparison subjects. Total MW performed during the 8 hr monitoring period was significantly reduced by 35% in the PWS group. The energy cost of physical activity is related to the duration, intensity and type of activity and the metabolic efficiency of the individual. After adjusting group differences in LBM by analysis of variance, TEE and REE were no longer different between the two groups. Our data indicate that there is a significant reduction of EE in individuals with PWS

  19. 6q16.3q23.3 duplication associated with Prader-Willi-like syndrome.

    Science.gov (United States)

    Desch, Laurent; Marle, Nathalie; Mosca-Boidron, Anne-Laure; Faivre, Laurence; Eliade, Marie; Payet, Muriel; Ragon, Clemence; Thevenon, Julien; Aral, Bernard; Ragot, Sylviane; Ardalan, Azarnouche; Dhouibi, Nabila; Bensignor, Candace; Thauvin-Robinet, Christel; El Chehadeh, Salima; Callier, Patrick

    2015-01-01

    Prader-Willi syndrome (PWS) is characterized by hypotonia, delayed neuropsychomotor development, overeating, obesity and mental deficiency. This phenotype is encountered in other conditions, defining Prader-Willi-like syndrome (PWLS). We report a 14-year-old boy with a complex small supernumerary marker chromosome (sSMC) associated with PWLS. The propositus presents clinical features commonly found in patients with PWLS, including growth hormone deficit. Banding karyotype analysis and fluorescence in situ hybridization (FISH) revealed a marker derived from chromosome 6 and a neocentromere as suspected, but array-CGH enabled us to characterize this marker as a der(10)t(6;10)(6qter → 6q23.3::10p11.1 → 10p11.21)dn. As far as we know, this is the first diagnosed case of PWLS associated with a complex sSMC, involving a 30.9 Mb gain in the 6q16.3q23.3 region and a 3.5 Mb gain in the 10p11.21p11.1 region. Several genes have been mapped to the 6q region including the TCBA1 gene, which is associated with developmental delay and recurrent infections, the ENPP1 gene, associated with insulin resistance and susceptibility to obesity and the BMIQ3 gene, associated with body mass index (BMI). No OMIM gene was found in the smallest 10p11.21p11.1 region. We suggest that the duplicated chromosome segment 6q16.3q23.3 may be responsible for the phenotype of our case and may also be a candidate locus of PWLS.

  20. State of the art in semiconductor detectors

    International Nuclear Information System (INIS)

    Rehak, P.; Gatti, E.

    1990-01-01

    The state of the art in semiconductor detectors for elementary particle physics and X-ray astronomy is briefly reviewed. Semiconductor detectors are divided into two groups; i) classical semiconductor diode detectors and ii) semiconductor memory detectors. Principles of signal formation for both groups of detectors are described and their performance is compared. New developments of silicon detectors are reported here. (orig.)

  1. State of the art in semiconductor detectors

    International Nuclear Information System (INIS)

    Rehak, P.; Gatti, E.

    1989-01-01

    The state of the art in semiconductor detectors for elementary particle physics and x-ray astronomy is briefly reviewed. Semiconductor detectors are divided into two groups; classical semiconductor diode detectors; and semiconductor memory detectors. Principles of signal formation for both groups of detectors are described and their performance is compared. New developments of silicon detectors are reported here. 13 refs., 8 figs

  2. First Case Report of Prader–Willi-Like Syndrome in Colombia

    Directory of Open Access Journals (Sweden)

    Estephania Candelo

    2018-03-01

    Full Text Available Background: Prader–Willi-like syndrome (PWLS is believed to be caused by a variety of disruptions in genetic pathways both inside and outside of the genetic region implicated in PWS. By definition, PWLS does not demonstrate mutations in the 15q11–q13 region itself. It is a rare disorder whose clinical hallmarks include hypotonia, obesity, short extremities, and delayed development. This syndrome has been described in patients with 1p, 2p, 3p, 6q, and 9q chromosome abnormalities and in cases with maternal uniparental disomy of chromosome 14 and fragile X syndrome.Case presentation: In the present report, we describe a 9-year-old Colombian patient who demonstrated features of PWS and was ultimately diagnosed with PWLS after genetic analysis revealed a 14.97 Mb deletion of 6q16.1–q21.Conclusions: This is the first reported case of PWLS in Colombia and represents one of the largest documented 6q21 deletions.

  3. First Case Report of Prader-Willi-Like Syndrome in Colombia.

    Science.gov (United States)

    Candelo, Estephania; Feinstein, Max M; Ramirez-Montaño, Diana; Gomez, Juan F; Pachajoa, Harry

    2018-01-01

    Background: Prader-Willi-like syndrome (PWLS) is believed to be caused by a variety of disruptions in genetic pathways both inside and outside of the genetic region implicated in PWS. By definition, PWLS does not demonstrate mutations in the 15q11-q13 region itself. It is a rare disorder whose clinical hallmarks include hypotonia, obesity, short extremities, and delayed development. This syndrome has been described in patients with 1p, 2p, 3p, 6q, and 9q chromosome abnormalities and in cases with maternal uniparental disomy of chromosome 14 and fragile X syndrome. Case presentation: In the present report, we describe a 9-year-old Colombian patient who demonstrated features of PWS and was ultimately diagnosed with PWLS after genetic analysis revealed a 14.97 Mb deletion of 6q16.1-q21. Conclusions: This is the first reported case of PWLS in Colombia and represents one of the largest documented 6q21 deletions.

  4. A new configuration of the Moxon-Rae detector based on Si detector

    International Nuclear Information System (INIS)

    Niu, H.; Hsu, J.Y.; Liang, J.H.; Yuan, L.G.

    2002-01-01

    A new Moxon-Rae detector configuration based on Si semiconductor detector was proposed in this paper. Three γ-ray sources, 137 Cs, 60 Co, and 24 Na, were employed to make actual measurements using the new Moxon-Rae detector. The measured pulse height spectra and detection efficiencies were compared with the EGS4 simulated values. The results revealed that the proposed new configuration is indeed a successful method and specially a useful technique for higher energy γ-ray measurement

  5. A comparative analysis of OTF, NPS, and DQE in energy integrating and photon counting digital x-ray detectors

    International Nuclear Information System (INIS)

    Acciavatti, Raymond J.; Maidment, Andrew D. A.

    2010-01-01

    is a binary function given as zero or unity everywhere. In analyzing the model detector with Gaussian blurring, the difference in NPS and DQE between the two detector types is found to increase with the blurring of the x-ray converter. Ultimately, the expression for the additive white noise of the photon counter is compared against the expression for electronic noise and secondary quantum noise in an energy integrator. Thus, a method is provided to determine the average secondary quanta that the energy integrator must produce for each x ray to have superior DQE to a photon counter with the same PSF. Conclusions: This article develops analytical models of OTF, NPS, and DQE for energy integrating and photon counting digital x-ray detectors. While many subtleties of real imaging systems have not been modeled, this work is illustrative in demonstrating an additive source of white noise in photon counting detectors which has not yet been described in the literature. One benefit of this analysis is a framework for determining the average secondary quanta that an energy integrating detector must produce for each x ray to have superior DQE to competing photon counting technology.

  6. Ruggedization of CdZnTe detectors and detector assemblies for radiation detection applications

    Energy Technology Data Exchange (ETDEWEB)

    Lu, P.H., E-mail: pinghe.lu@redlen.com; Gomolchuk, P.; Chen, H.; Beitz, D.; Grosser, A.W.

    2015-06-01

    This paper described improvements in the ruggedization of CdZnTe detectors and detector assemblies for use in radiation detection applications. Research included experimenting with various conductive and underfill adhesive material systems suitable for CZT substrates. A detector design with encapsulation patterning was developed to protect detector surfaces and to control spacing between CZT anode and PCB carrier. Robustness of bare detectors was evaluated through temperature cycling and metallization shear testing. Attachment processes using well-chosen adhesives and PCB carrier materials were optimized to improve reliability of detector assemblies, resulted in Improved Attachment Detector Assembly. These detector assemblies were subjected to aggressive temperature cycling, and varying levels of drop/shock and vibration, in accordance with modified JEDEC, ANSI and FedEx testing standards, to assess their ruggedness. Further enhanced detector assembly ruggedization methods were investigated involving adhesive conformal coating, potting and dam filling on detector assemblies, which resulted in the Enhanced Ruggedization Detector Assembly. Large numbers of CZT detectors and detector assemblies with 5 mm and 15 mm thick, over 200 in total, were tested. Their performance was evaluated by exposure to various radioactive sources using comprehensive predefined detector specifications and testing protocols. Detector assemblies from improved attachment and enhanced ruggedization showed stable performances during the harsh environmental condition tests. In conclusion, significant progress has been made in improving the reliability and enhancing the ruggedness of CZT detector assemblies for radiation detection applications deployed in operational environments. - Highlights: • We developed ruggedization methods to enhance reliability of CZT detector assemblies. • Attachment of CZT radiation detectors was improved through comparative studies. • Bare detector metallization

  7. Compound Semiconductor Radiation Detector

    International Nuclear Information System (INIS)

    Kim, Y. K.; Park, S. H.; Lee, W. G.; Ha, J. H.

    2005-01-01

    In 1945, Van Heerden measured α, β and γ radiations with the cooled AgCl crystal. It was the first radiation measurement using the compound semiconductor detector. Since then the compound semiconductor has been extensively studied as radiation detector. Generally the radiation detector can be divided into the gas detector, the scintillator and the semiconductor detector. The semiconductor detector has good points comparing to other radiation detectors. Since the density of the semiconductor detector is higher than that of the gas detector, the semiconductor detector can be made with the compact size to measure the high energy radiation. In the scintillator, the radiation is measured with the two-step process. That is, the radiation is converted into the photons, which are changed into electrons by a photo-detector, inside the scintillator. However in the semiconductor radiation detector, the radiation is measured only with the one-step process. The electron-hole pairs are generated from the radiation interaction inside the semiconductor detector, and these electrons and charged ions are directly collected to get the signal. The energy resolution of the semiconductor detector is generally better than that of the scintillator. At present, the commonly used semiconductors as the radiation detector are Si and Ge. However, these semiconductor detectors have weak points. That is, one needs thick material to measure the high energy radiation because of the relatively low atomic number of the composite material. In Ge case, the dark current of the detector is large at room temperature because of the small band-gap energy. Recently the compound semiconductor detectors have been extensively studied to overcome these problems. In this paper, we will briefly summarize the recent research topics about the compound semiconductor detector. We will introduce the research activities of our group, too

  8. Integrated double-sided silicon microstrip detectors

    Directory of Open Access Journals (Sweden)

    Perevertailo V. L.

    2011-11-01

    Full Text Available The problems of design, technology and manufacturing double-sided silicon microstrip detectors using standard equipment production line in mass production of silicon integrated circuits are considered. The design of prototype high-energy particles detector for experiment ALICE (CERN is presented. The parameters of fabricated detectors are comparable with those of similar foreign detectors, but they are distinguished by lesser cost.

  9. Identification of Prader-Willi Syndrome mosaicism by fluorescent in situ hybridization

    Energy Technology Data Exchange (ETDEWEB)

    Mowery-Rushton, P.A.; Surti, U. [Magee Womens Hospital, Pittsburgh, PA (United States); Hanchett, J.M. [Rehabilitation Institute, Pittsburgh, PA (United States)

    1994-09-01

    Prader-Willi Syndrome (PWS) is a microdeletion syndrome involving an interstitial deletion of region q11-q13 on the paternal chromosome 15. We report 2 cases of PWS that were analyzed using FISH and were found to be mosaic for a normal cell line and a deleted cell line. Case 1 was diagnosed as an atypical PWS who was cytogenetically normal. She is a 38 y.o. white female displaying some but not all of the features of PWS. Case 2 is a 23 y.o. white male with a classical deletion of chromosome 15q11-q13. He displays very typical features of PWS. He was also noted to be albino. FISH analysis was performed on PHA stimulated lymphocytes. We examined four loci: D15S11, SNRPN, D15S10, and GABRB3. The number of cells examined for each locus ranged from 46 to 75. Case 1 was deleted at 3 of the 4 loci (D15S11, SNRPN and GABRB3) in 30% of her cells. The D15S10 locus was not deleted. This may account for the atypical features displayed by this patient. It also suggests that this chromosome is rearranged resulting in the retention of the interstitial locus. The exact nature of the rearrangement needs to be determined. Case 2 was deleted at all four loci in 60% of the cells analyzed. This result was unexpected because his deletion was identified cytogenetically, but mosaicism was not detected. These are the first reported cases of mosaic PWS diagnosed using FISH. The use of cytogenetics alone requires high resolution banding to accurately identify the deletion. This makes the detection of small deletions in every cell difficult and the determination of mosaicism almost impossible. Our results suggest that mosaicism may be occurring more frequently than previously thought and may account for some of the atypical cases. Studies are in progress to determine the effect of mosaicism on methylation at genes located within this region which are imprinted and are thought to be involved in the etiology of Prader-Willi Syndroms.

  10. Monitor for reactor neutron detector

    International Nuclear Information System (INIS)

    Shirakami, Hisayuki; Shibata, Masatoshi

    1992-01-01

    The device of the present invention judges as to whether a neutron detector is normal or not while considering the change of indication value depending on the power change of a reactor core. That is, the device of the present invention comprises a standard value setting device for setting the standard value for calibrating the neutron detector and an abnormality judging device for comparing the standard value with a measured value of the neutron detector and judging the abnormality when the difference is greater than a predetermined value. The measured value upon initialization of each of the neutron detectors is determined as a quasi-standard value. An average value of the difference between the measured value and the quasi-standard value of a plurality of effective neutron detectors at a same level for the height of the reactor core is multiplied to a power rate based on the reactor core power at a position where the neutron detector is disposed upon calibration. The value obtained by adding the multiplied value and the quasi-standard value is determined as a standard value. The abnormality judging device compares the standard value with the measured value of the neutron detector and, if the difference is greater than a predetermined value, the neutron detector is determined as abnormal. As a result, judgement can be conducted more accurately than conventional cases. (I.S.)

  11. Síndrome de Prader Willi: Presentación clínica de dos pacientes y revisión de la literatura Prader-Willi syndrome: Clinical report of two patients and literature review

    Directory of Open Access Journals (Sweden)

    Nuris Rodríguez Vargas

    2006-03-01

    Full Text Available El síndrome de Prader Willi es una afección de niños y jóvenes caracterizada por obesidad, baja talla, oligofrenia, llanto débil o gemido, hipoplasia de los escrotos, testículos no descendidos, entre otros. En la pubertad se asocia a un desarrollo demorado e incompleto y a la aparición de diabetes mellitus y elevada excreción de gonadotropina. Presentamos en este trabajo a dos pacientes que cumplen estos criterios clínicos y que fueron estudiados en el Policlínico Docente «19 de Abril». Se realiza una breve revisión bibliográfica del síndrome.

  12. Low prevalence of collateral cerebral circulation in the circle of Willis in patients with severe carotid artery stenosis and recent ischemic stroke.

    Science.gov (United States)

    Badacz, Rafał; Przewłocki, Tadeusz; Karch, Izabela; Pieniążek, Piotr; Rosławiecka, Agnieszka; Mleczko, Szymon; Brzychczy, Andrzej; Trystuła, Mariusz; Żmudka, Krzysztof; Kabłak-Ziembicka, Anna

    2015-01-01

    The circle of Willis is thought to play a key role in development of collateral flow in patients with internal carotid artery stenosis (ICAS). To assess flow in the circle of Willis in patients with recent ischemic stroke (IS). The study included 371 patients, 102 symptomatic with severe ICAS and recent IS (within the last 3 months) (group I) and 269 asymptomatic with severe ICAS (group II). Flow in the middle (MCA), anterior (ACA) and posterior (PCA) cerebral arteries and pattern of the cross-flow through anterior (ACoA) and posterior (PCoA) communicating arteries were assessed with transcranial color-coded Doppler ultrasonography (TCCD). The ACoA or PCoA was less prevalent in group I than in group II (54% vs. 78%, p PCoA and higher PSV in the MCA and ACA were associated with significant risk reduction of IS (RR = 0.28 (95% CI = 0.16-0.49, p PCoA seem to play a key role in the evaluation of IS risk in subjects with severe ICAS.

  13. The AFP Detector Control System

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00514541; The ATLAS collaboration

    2017-01-01

    The ATLAS Forward Proton (AFP) detector is one of the forward detectors of the ATLAS experiment at CERN aiming at measuring momenta and angles of diffractively scattered protons. Silicon Tracking and Time-of-Flight detectors are located inside Roman Pot stations inserted into beam pipe aperture. The AFP detector is composed of two stations on each side of the ATLAS interaction point and is under commissioning. The detector is provided with high and low voltage distribution systems. Each station has vacuum and cooling systems, movement control and all the required electronics for signal processing. Monitoring of environmental parameters, like temperature and radiation, is also available. The Detector Control System (DCS) provides control and monitoring of the detector hardware and ensures the safe and reliable operation of the detector, assuring good data quality. Comparing with DCS systems of other detectors, the AFP DCS main challenge is to cope with the large variety of AFP equipment. This paper describes t...

  14. The AFP detector control system

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00514541; The ATLAS collaboration; Caforio, Davide; Czekierda, Sabina; Hajduk, Zbigniew; Olszowska, Jolanta; Sicho, Petr; Zabinski, Bartlomiej

    The ATLAS Forward Proton (AFP) detector is one of the forward detectors of the ATLAS experiment at CERN aiming at measuring momenta and angles of diffractively scattered protons. Silicon Tracking and Time-of-Flight detectors are located inside Roman Pot stations inserted into beam pipe aperture. The AFP detector is composed of two stations on each side of the ATLAS interaction point and is under commissioning. The detector is provided with high and low voltage distribution systems. Each station has vacuum and cooling systems, movement control and all the required electronics for signal processing. Monitoring of environmental parameters, like temperature and radiation, is also available. The Detector Control System (DCS) provides control and monitoring of the detector hardware and ensures the safe and reliable operation of the detector, assuring good data quality. Comparing with DCS systems of other detectors, the AFP DCS main challenge is to cope with the large variety of AFP equipment. This paper describes t...

  15. The importance of the time scale in radiation detection exemplified by comparing conventional and avalache semiconductor detectors

    Energy Technology Data Exchange (ETDEWEB)

    Tove, P A; Cho, Z H; Huth, G C [California Univ., Los Angeles (USA). Lab. of Nuclear Medicine and Radiation Biology

    1976-02-01

    The profound importance of the time scale of a radiation detection process is discussed in an analysis of limitations in energy resolution and timing, with emphasis on semiconductor detectors used for X-ray detection. The basic event detection time involves stopping of the particle and creating a distribution of free electrons and holes containing all desired information (energy, time position) about the particle or quantum, in a time approximately equal to 10/sup -12/s. The process of extracting this information usually involves a much longer time because the signal is generated in the relatively slow process of charge collection, and further prolongation may be caused by signal processing required to depress noise for improving energy resolution. This is a common situation for conventional semiconductor detectors with external amplifiers where time constants of 10/sup -5/-10/sup -4/s may be optimum, primarily because of amplifier noise. A different situation applies to the avalanche detector where internal amplification helps in suppressing noise without expanding the time scale of detections, resulting in an optimum time of 10/sup -9/-10/sup -8/s. These two cases are illustrated by plotting energy resolution vs. time constant, for different magnitudes of the parallel and series type noise sources. The effects of the inherent energy spread due to statistips and spatial inhomogeneities are also discussed to illustrate the potential of these two approaches for energy and time determination. Two constructional approaches for avalanche detectors are briefly compared.

  16. Neutron beam imaging with GEM detectors

    International Nuclear Information System (INIS)

    Albani, G.; Cazzaniga, C.; Rebai, M.; Gorini, G.; Croci, G.; Muraro, A.; Cippo, E. Perelli; Tardocchi, M.; Cavenago, M.; Murtas, F.; Claps, G.; Pasqualotto, R.

    2015-01-01

    Neutron GEM-based detectors represent a new frontier of devices in neutron physics applications where a very high neutron flux must be measured such as future fusion experiments (e.g. ITER Neutral beam Injector) and spallation sources (e.g. the European Spallation source). This kind of detectors can be properly adapted to be used both as beam monitors but also as neutron diffraction detectors that could represent a valid alternative for the 3 He detectors replacement. Fast neutron GEM detectors (nGEM) feature a cathode composed by one layer of polyethylene and one of aluminium (neutron scattering on hydrogen generates protons that are detected in the gas) while thermal neutron GEM detectors (bGEM) are equipped with a borated aluminium cathode (charged particles are generated through the 10 B(n,α) 7 Li reaction). GEM detectors can be realized in large area (1 m 2 ) and their readout can be pixelated. Three different prototypes of nGEM and one prototype of bGEM detectors of different areas and equipped with different types of readout have been built and tested. All the detectors have been used to measure the fast and thermal neutron 2D beam image at the ISIS-VESUVIO beamline. The different kinds of readout patterns (different areas of the pixels) have been compared in similar conditions. All the detectors measured a width of the beam profile consitent with the expected one. The imaging property of each detector was then tested by inserting samples of different material and shape in the beam. All the samples were correctly reconstructed and the definition of the reconstruction depends on the type of readout anode. The fast neutron beam profile reconstruction was then compared to the one obtained by diamond detectors positioned on the same beamline while the thermal neutron one was compared to the imaged obtained by cadmium-coupled x-rays films. Also efficiency and the gamma background rejection have been determined. These prototypes represent the first step towards

  17. Types of the cerebral arterial circle (circle of Willis in a Sri Lankan Population

    Directory of Open Access Journals (Sweden)

    Gunasekera WSL

    2011-01-01

    Full Text Available Abstract Background The variations of the circle of Willis (CW are clinically important as patients with effective collateral circulations have a lower risk of transient ischemic attack and stroke than those with ineffective collaterals. The aim of the present cadaveric study was to investigate the anatomical variations of the CW and to compare the frequency of prevalence of the different variations with previous autopsy studies as variations in the anatomy of the CW as a whole have not been studied in the Indian subcontinent. Methods The external diameter of all the arteries forming the CW in 225 normal Sri Lankan adult cadaver brains was measured using a calibrated grid to determine the prevalence in the variation in CW. Chisquared tests and a correspondence analysis were performed to compare the relative frequencies of prevalence of anatomical variations in the CW across 6 studies of diverse ethnic populations. Results We report 15 types of variations of CW out of 22 types previously described and one additional type: hypoplastic precommunicating part of the anterior cerebral arteries (A1 and contralateral posterior communicating arteries (PcoA 5(2%. Statistically significant differences (p Conclusion The present study reveals that there are significant variations in the CW among intra and inter ethnic groups (Caucasian, African and Asian: Iran and Sri Lanka dominant populations, and warrants further studies keeping the methods of measurements, data assessment, and the definitions of hypoplasia the same.

  18. Computed tomography apparatus with detector sensilivity correction

    International Nuclear Information System (INIS)

    Waltham, R. M.

    1984-01-01

    In a rotary fan beam computed tomography apparatus using recurrent relative displacement between the source and detectors (e.g. a deflected spot X-ray tube) for the recalibration of detectors in chain-like sequences across the detector array by successive pairwise common-path sensitivity comparisons starting from a terminal detector each sequence normally involves or more successive comparisons, and consistent but unpredictable errors are found to occur, leading to incorrect Houndsfield values in the computed image matrix. The improvement comprises locating at least one radiation transparent detector of high stability in front of the array at an intermediate point and using the output to further correct the chain-corrected detector sensitivity values. A detector comprising a plastics scintillator optically coupled to a photomultiplier is described, whose output pulses are counted during a rotational scan and compared with the mean corresponding measurement from detectors lying behind the detector, to form a sensitivity ratio. From a corresponding ratio and data derived during calibration, a measured sensitivity value for detectors is determined for each scan and is compared with the corresponding chain-corrected sensitivity value to generate a further sensitivity correction value which is then distributed among the detectors of the comparison sequence

  19. [Care continuity for patients with Prader-Willi syndrome during transition from childhood to adulthood].

    Science.gov (United States)

    Saitoh, Shinji

    2010-01-01

    Prader-Willi syndrome(PWS) is a complex multisystem genetic disorder, of which characteristic phenotypes include neonatal hypotonia, hyperphagia resulting in obesity, mental retardation, hypogonadism, and behavioral and psychiatric problems. The diagnosis can be obtained as early as during neonatal period thanks to development of genetic testing. Clinical features of PWS will change depending on age, although core phenotypes of hyperphagia, obesity and psychiatric issues stay for lifetime. Therefore, integrated multidisciplinary approach starting from neonatal period is mandatory to ensure optimal management to improve lifelong quality of life. For successful transition from childhood to adulthood, multidisciplinary team need to share clinical information, and should keep the same policy about food, environment and psychiatric issues.

  20. Semiconductor detectors in nuclear and particle physics

    International Nuclear Information System (INIS)

    Rehak, P.; Gatti, E.

    1992-01-01

    Semiconductor detectors for elementary particle physics and nuclear physics in the energy range above 1 GeV are briefly reviewed. In these two fields semiconductor detectors are used mainly for the precise position sensing. In a typical experiment, the position of a fast charged particle crossing a relatively thin semiconductor detector is measured. The position resolution achievable by semiconductor detectors is compared with the resolution achievable by gas filled position sensing detectors. Semiconductor detectors are divided into two groups: Classical semiconductor diode detectors and semiconductor memory detectors. Principles of the signal formation and the signal read-out for both groups of detectors are described. New developments of silicon detectors of both groups are reported

  1. The neurobiological drive for overeating implicated in Prader-Willi syndrome.

    Science.gov (United States)

    Zhang, Yi; Wang, Jing; Zhang, Guansheng; Zhu, Qiang; Cai, Weiwei; Tian, Jie; Zhang, Yi Edi; Miller, Jennifer L; Wen, Xiaotong; Ding, Mingzhou; Gold, Mark S; Liu, Yijun

    2015-09-16

    Prader-Willi syndrome (PWS) is a genetic imprinting disorder characterized mainly by hyperphagia and early childhood obesity. Previous fMRI studies examined the activation of eating-related neural circuits in PWS patients with or without exposures to food cues and found an excessive eating motivation and a reduced inhibitory control of cognitive processing of food. However, the effective connectivity between various brain areas or neural circuitry critically implicated in both the biological and behavioral control of overeating in PWS is largely unexplored. The current study combined resting-state fMRI and Granger causality analysis (GCA) techniques to investigate interactive causal influences among key neural pathways underlying overeating in PWS. We first defined the regions of interest (ROIs) that demonstrated significant alterations of the baseline brain activity levels in children with PWS (n = 21) as compared to that of their normal siblings controls (n = 18), and then carried out GCA to characterize the region-to-region interactions among these ROIs. Our data revealed significantly enhanced causal influences from the amygdala to the hypothalamus and from both the medial prefrontal cortex and anterior cingulate cortex to the amygdala in patients with PWS (P < 0.001). These alterations offer new explanations for hypothalamic regulation of homeostatic energy intake and impairment in inhibitory control circuit. The deficits in these dual aspects may jointly contribute to the extreme hyperphagia in PWS. This study provides both a new methodological and a neurobiological perspective to aid in a better understanding of neural mechanisms underlying obesity in the general public. This article is part of a Special Issue entitled 1618. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. Perfil comportamental e cognitivo de crianças com a síndrome de Prader Willi

    OpenAIRE

    Maria Luiza Guedes de Mesquita

    2008-01-01

    A Síndrome de Prader Willi (SPW) é uma doença genética de origem paterna causada pela perda de expressão de genes no cromossomo 15. Alguns sintomas patognomônicos da doença são a hiperfagia e a obesidade que, na maioria dos casos, ocorre antes dos seis anos e compromete severamente a qualidade vida desses pacientes. O presente estudo se concentrou na área comportamental e teve como objetivos: - identificar a freqüência diária de comportamentos alimentares e ingestão calórica de crianças com S...

  3. Characterization of HPGe detectors using Computed Tomography

    Energy Technology Data Exchange (ETDEWEB)

    Hedman, A., E-mail: Angelica.Hedman@foi.se [Swedish Defence Research Agency, Division of CBRN Defence and Security, SE-90182 Umeå (Sweden); Umeå University, Department of Radiation Sciences, Radiation Physics, SE-90187 Umeå (Sweden); Bahar Gogani, J.; Granström, M. [Swedish Defence Research Agency, Division of CBRN Defence and Security, SE-90182 Umeå (Sweden); Johansson, L.; Andersson, J.S. [Umeå University, Department of Radiation Sciences, Radiation Physics, SE-90187 Umeå (Sweden); Ramebäck, H. [Swedish Defence Research Agency, Division of CBRN Defence and Security, SE-90182 Umeå (Sweden); Chalmers University of Technology, Department of Chemical and Biological Engineering, Nuclear Chemistry, SE-41296 Göteborg (Sweden)

    2015-06-11

    Computed Tomography (CT) high-resolution imaging have been used to investigate if there is a significant change in the crystal-to-window distance, i.e. the air gap thickness, in a small n-type detector cooled to 77 K, and in a medium sized p-type HPGe detector when cooled to 100 K. The findings were compared to detector dimension data made available by the manufacturer. The air gap thickness increased by (0.38±0.07) mm for the n-type detector and by (0.40±0.15) mm for the p-type detector when the detectors were cooled to 77 resp. 100 K compared to at room temperature. Monte Carlo calculations indicate that these differences have a significant impact on the efficiency in close geometries (<5 cm). In the energy range of 40–700 keV with a source placed directly on endcap, the change in detector efficiency with temperature is 1.9–2.9% for the n-type detector and 0.3–2.1% for the p-type detector. The measured air gap thickness when cooling the detector was 1.1 mm thicker than manufacturer data for the n-type detector and 0.2 mm thicker for the p-type detector. In the energy range of 40–700 keV and with a source on endcap, this result in a change in detector efficiency of 5.2–7.1% for the n-type detector and 0.2–1.0% for the p-type detector, i.e. the detector efficiency is overestimated using data available by the manufacturer.

  4. Prader-Willi syndrome and Tay-Sachs disease in association with mixed maternal uniparental isodisomy and heterodisomy 15 in a girl who also had isochromosome Xq.

    Science.gov (United States)

    Zeesman, Susan; McCready, Elizabeth; Sadikovic, Bekim; Nowaczyk, Małgorzata Jm

    2015-01-01

    Malsegregation of chromosomes during reproduction can result in uniparental disomy when associated with trisomy rescue, monosomy rescue or gamete complementation. Pathogenicity stemming from uniparental disomy in liveborns results from imprinting disorders or autozygosity for autosomal recessive disorders. We report on a girl with Prader-Willi syndrome and Tay-Sachs disease resulting from maternal uniparental disomy of chromosome 15. The child also had an isochromosome Xq. To further characterize the etiology of the aberrant chromosome 15 and the isochromosome Xq, SNP loci from both chromosomes were assessed in the proband and parents, and genome-wide DNA methylation analysis was performed. SNP and DNA methylation analysis confirmed maternal uniparental heterodisomy around the Prader-Willi locus, while the region around the HEXA locus showed maternal uniparental isodisomy. This result is consistent with trisomy rescue of a maternal meiosis l error in a chromosome 15 with two meiotic recombinations. SNP analysis of the X chromosomes is consistent with a maternal origin for the isochromosome. © 2014 Wiley Periodicals, Inc.

  5. Semiconductor detectors in nuclear and particle physics

    International Nuclear Information System (INIS)

    Rehak, P.; Gatti, E.

    1995-01-01

    Semiconductor detectors for elementary particle physics and nuclear physics in the energy range above 1 GeV are briefly reviewed. In these two fields semiconductor detectors are used mainly for the precise position sensing. In a typical experiment, the position of a fast charged particle crossing a relatively thin semiconductor detector is measured. The position resolution achievable by semiconductor detectors is compared with the resolution achievable by gas filled position sensing detectors. Semiconductor detectors are divided into two groups; (i) classical semiconductor diode detectors and (ii) semiconductor memory detectors. Principles of the signal formation and the signal read-out for both groups of detectors are described. New developments of silicon detectors of both groups are reported. copyright 1995 American Institute of Physics

  6. Weight control and behavior rehabilitation in a patient suffering from Prader Willi syndrome.

    Science.gov (United States)

    Di Lorenzo, Rosaria; Sberveglieri, Sara; Marrama, Donatella; Landi, Giulia; Ferri, Paola

    2016-04-01

    This study reports a case of Prader Willi syndrome (PWS), a genomic imprinting disease related to chromosome regions 15q11.2-q13 15, which includes hypothalamic dysfunction leading to hyperphagia, obesity, shortness, sleep abnormalities. Our case is extremely severe, in comparison to other PWS cases described in literature, due to the association with severe emotional and psychiatric symptoms: oppositional behaviour, rigidity of thought, skin picking and pathological hoarding. We described the case of a Caucasian male patient suffering from PWS, treated in outpatient care by local Mental Health Centre and supported by Social Service, who was admitted to a residential rehabilitative facility. After a 2-year follow-up, the patient showed a global improvement in symptoms and functioning, as registered by the rating scales administered. At the end of observation period, we also reported an important improvement in weight control, reducing the risk of obesity and related diseases, therefore improving the prognosis of life. This case highlights the need for long-term, individualized and multi-professional treatment in patients suffering from a complex genetic syndrome with both organic and psychological alterations, for which medical care setting and pharmacological treatments are not sufficient. Clinical observation of this case leads us to compare PWS to drug addiction and indirectly endorse the neurophysiological hypothesis that food and drugs stimulate the same brain circuits in the limbic system.

  7. Development of leak detector by radiation. 2

    International Nuclear Information System (INIS)

    Suzuki, Takashi; Okano, Yasuhiro; Chisaka, Haruo

    1997-01-01

    Leak detector by radiation has been developed by cooperative research between Water Authority and us. In his fiscal year, the most suitable arrangement of detector system was simulated by Monte Carlo method. The first, the experimental values were compared with the results of simulation. The second, calculation was carried out by changing the quality of reflective materials and distance between radiation source and detector. The simulation results were agreed with the experimental results. On the basis of the rate of presence of leak, the most suitable arrangement of detector system was obtained under the conditions that both radiation source and detector covered with graphite or iron of 5 cm thickness and separated each other 3 cm apart. However, by comparing FOM (figure of merit), the suitable arrangement was that radiation source and detector adjoined each other and covered by graphite or iron of 20 cm thickness. (S.Y.)

  8. SoLid Detector Technology

    Science.gov (United States)

    Labare, Mathieu

    2017-09-01

    SoLid is a reactor anti-neutrino experiment where a novel detector is deployed at a minimum distance of 5.5 m from a nuclear reactor core. The purpose of the experiment is three-fold: to search for neutrino oscillations at a very short baseline; to measure the pure 235U neutrino energy spectrum; and to demonstrate the feasibility of neutrino detectors for reactor monitoring. This report presents the unique features of the SoLid detector technology. The technology has been optimised for a high background environment resulting from low overburden and the vicinity of a nuclear reactor. The versatility of the detector technology is demonstrated with a 288 kg detector prototype which was deployed at the BR2 nuclear reactor in 2015. The data presented includes both reactor on, reactor off and calibration measurements. The measurement results are compared with Monte Carlo simulations. The 1.6t SoLid detector is currently under construction, with an optimised design and upgraded material technology to enhance the detector capabilities. Its deployement on site is planned for the begin of 2017 and offers the prospect to resolve the reactor anomaly within about two years.

  9. An 18-year-old patient with Prader-Willi syndrome: a case report on dental management under sedation and general anesthesia

    OpenAIRE

    Song, Ki Un; Nam, Ok Hyung; Kim, Mi Sun; Choi, Sung Chul; Lee, Hyo-Seol

    2015-01-01

    Prader-Willi syndrome (PWS) is a rare genetic disorder reported rarely in dentistry. Dental practitioners should know the features of PWS because affected patients have a variety of dental symptoms. The current report describes a case of PWS. An 18-year-old male patient presented with traumatic injuries. Initial emergency treatments were performed under sedation, and further treatments were conducted under general anesthesia. After adequate healing, periodic follow-up and dietary management a...

  10. Serum adiponectin levels in adults with Prader-Willi syndrome are independent of anthropometrical parameters and do not change with GH treatment

    DEFF Research Database (Denmark)

    Hoybye, Charlotte; Bruun, Jens M; Richelsen, Bjorn

    2004-01-01

    it of interest to measure adiponectin levels in PWS. PATIENTS AND METHODS: 17 adults, nine men and eight women, 17 to 32 years of age, with a mean body mass index (BMI) of 35+/-3.2 kg/m2 participated. All had clinical PWS. They were randomized to treatment with placebo or GH (Genotropin) for six months......OBJECTIVE: Obesity and growth hormone (GH) deficiency are common in Prader-Willi syndrome (PWS) and these patients are at risk of metabolic diseases in adult life and of reduced life span. Low adiponectin values are associated with obesity and the metabolic syndrome. We therefore found......, and subsequently all received GH for 12 months. At baseline, serum total adiponectin levels in the PWS patients were compared with 25 lean and 34 obese controls. Body composition and various metabolic parameters, including adiponectin, were studied every six months in the PWS group. RESULTS: Serum adiponectin...

  11. Monte Carlo simulation of a CZT detector

    International Nuclear Information System (INIS)

    Chun, Sung Dae; Park, Se Hwan; Ha, Jang Ho; Kim, Han Soo; Cho, Yoon Ho; Kang, Sang Mook; Kim, Yong Kyun; Hong, Duk Geun

    2008-01-01

    CZT detector is one of the most promising radiation detectors for hard X-ray and γ-ray measurement. The energy spectrum of CZT detector has to be simulated to optimize the detector design. A CZT detector was fabricated with dimensions of 5x5x2 mm 3 . A Peltier cooler with a size of 40x40 mm 2 was installed below the fabricated CZT detector to reduce the operation temperature of the detector. Energy spectra of were measured with 59.5 keV γ-ray from 241 Am. A Monte Carlo code was developed to simulate the CZT energy spectrum, which was measured with a planar-type CZT detector, and the result was compared with the measured one. The simulation was extended to the CZT detector with strip electrodes. (author)

  12. Modeling of diamond radiation detectors

    International Nuclear Information System (INIS)

    Milazzo, L.; Mainwood, A.

    2004-01-01

    We have built up a computer simulation of the detection mechanism in the diamond radiation detectors. The diamond detectors can be fabricated from a chemical vapour deposition polycrystalline diamond film. In this case, the trapping-detrapping and recombination at the defects inside the grains and at the grain boundaries degrade the transport properties of the material and the charge induction processes. These effects may strongly influence the device's response. Previous simulations of this kind of phenomena in the diamond detectors have generally been restricted to the simple detector geometries and homogeneous distribution of the defects. In our model, the diamond film (diamond detector) is simulated by a grid. We apply a spatial and time discretization, regulated by the grid resolution, to the equations describing the charge transport and, by using the Shockley-Ramo theorem, we calculate the signal induced on the electrodes. In this way, we can simulate the effects of the nonhomogeneous distributions of the trapping, recombination, or scattering centers and can investigate the differences observed when different particles, energies, and electrode configurations are used. The simulation shows that the efficiency of the detector increases linearly with the average grain size, that the charge collection distance is small compared to the dimensions of a single grain, and that for small grains, the trapping at the intragrain defects is insignificant compared to the effect of the grain boundaries

  13. Special Care Dentistry in a Patient with Prader–Willi Syndrome through the Use of Atraumatic Restorative Treatment under General Anesthesia

    OpenAIRE

    Caio Vinícius Gonçalves Roman-Torres; Sérgio Takashi Kussaba; Yasmin Comoti Vita Bantim; Roberta de Barros Antunes Almeida de Oliveira

    2017-01-01

    Prader–Willi syndrome described in 1956 has a genetic origin, affecting both genders, varying in presence and intensity from individual to individual. A precocious diagnosis, before the manifestation of symptoms, has brought some improvement in the quality of life of the carriers in the last years. The objective of this case report was to describe the treatment realized in a 3-year-old boy who presented grade II obesity, difficulty of locomotion, hypotonia, and history of cardiopathy. A denta...

  14. Comparative study of afterpulsing behavior and models in single photon counting avalanche photo diode detectors.

    Science.gov (United States)

    Ziarkash, Abdul Waris; Joshi, Siddarth Koduru; Stipčević, Mario; Ursin, Rupert

    2018-03-22

    Single-photon avalanche diode (SPAD) detectors, have a great importance in fields like quantum key distribution, laser ranging, florescence microscopy, etc. Afterpulsing is a non-ideal behavior of SPADs that adversely affects any application that measures the number or timing of detection events. Several studies based on a few individual detectors, derived distinct mathematical models from semiconductor physics perspectives. With a consistent testing procedure and statistically large data sets, we show that different individual detectors - even if identical in type, make, brand, etc. - behave according to fundamentally different mathematical models. Thus, every detector must be characterized individually and it is wrong to draw universal conclusions about the physical meaning behind these models. We also report the presence of high-order afterpulses that are not accounted for in any of the standard models.

  15. Specific characteristics of radon passive/open model detectors compared to passive/close and charcoal devices

    International Nuclear Information System (INIS)

    Andru, J.

    1990-01-01

    All passive/open detectors, also called Unfiltered alpha Track Detectors (UTDs), are built around KODAK LR115 film, only material sensitive to all ambient alpha particles and capable to work in open mode. The principle of open detectors is not new. They are largely used worldwide, often by scientists (in France, Italy, Japan, Norway, Sweden etc.). However, their particular functioning needs some explanation and some reminders. This paper is more aimed to discuss generalities than details of calculation. The estimation of the Potential Alpha Energy (PAE) concentration is about 4 times better than that from other passive detectors and it includes thoron progeny. The film is more sensitive to ambient decay products than it is to Radon as track count is higher for alpha's of greater initial energy

  16. Prader Willi Syndrome: A Family's Experience

    Directory of Open Access Journals (Sweden)

    Emma Walker

    2006-01-01

    Full Text Available Genetic research has offered, and continues to offer, a medical explanation of chromosomal disorders such as Down Syndrome and Asberger Syndrome and more recently the rare chromosomal disorder Prader Willi Syndrome. This research gives a pathogenic explanation of disorders which includes historical background, genetic defects and clinical features. This study set out to offer an insight into the effects of PWS on the child and his/her family. It also aimed to highlight what support systems are in place in the Co. Louth area of Ireland for individuals with PWS. Unfortunately, PWS is not curable at this time. Between 1995-2003 there were 39 diagnosed cases of PWS in Ireland, an average of 4.3 per year. On average there are four infants or children diagnosed in Ireland with PWS per year (Turner, 2004, National Centre for Medical Genetics. This study is an exploratory and descriptive case study. This case study drew on multiple sources of evidence to construct a valid and unique illustration of PWS. The primary source of data was derived from in-depth interviews with the parents of a 3-year-old girl who has PWS. She was diagnosed during the third week of life. The evidence of this study suggests that non-specialist medical staff are not generally familiar with PWS. Training in relation to diagnostic criteria for chromosomal disorders would be extremely beneficial to them and to familes that are affected by the syndrome. This study highlights the need for parents to be their own child's advocate in obtaining desired support services for their area. Support services in the North East region have been greatly increased due to the setting up of the North Eastern Health Board (now known as Health Service Executive, North East Region Early Intervention Services (EIS in 2000.

  17. MR of the pituitary in patients with Prader-Willi syndrome: size determination and imaging findings

    Energy Technology Data Exchange (ETDEWEB)

    Miller, L. [Dept. of Radiology, Winthrop University Hospital, Mineola, NY (United States); Angulo, M. [Dept. of Pediatrics, Div. of Endocrinology and Genetics, Winthrop University Hospital, Mineola, NY (United States); Price, D. [Dept. of Radiology, Winthrop University Hospital, Mineola, NY (United States); Taneja, S. [Dept. of Radiology, Winthrop University Hospital, Mineola, NY (United States)

    1996-01-01

    Prader-Willi syndrome (PWS) is an unusual genetic disorder characterized by short stature, obesity, hypogonadism, hypotonia, cognitive impairment, and dysmorphic facies. There is an interstitial deletion of the proximal long arm of chromosome 15 in about 70% of patients. Some of these clinical features suggest a central hypothalamic/pituitary dysfunction, and recent investigations have demonstrated a marked impairment in spontaneous growth hormone (GH) secretion. We studied 15 GH-deficient PWS patients by magnetic resonance imaging (MRI) to determine whether there was a diminution in the gross morphological size of the anterior pituitary gland, the site of GH synthesis. We also set out to catalog the pertinent imaging findings in this patient population. Our results indicate that this is the first report documenting pituitary size by MRI in PWS patients. No statistically significant difference was found in the height of the anterior pituitary gland in PWS patients compared with either normal children or children with isolated GH deficiency. An interesting imaging finding is that three of 15 patients (20%) demonstrated complete absence of the posterior pituitary bright spot (PPBS), and a fourth patient demonstrated a small PPBS. These observations reflect an objective physiologic disturbance in the hypothalamus. The clinical and radiologic implications of these findings are discussed. (orig.)

  18. Silicon Pixel Detectors for Synchrotron Applications

    CERN Document Server

    Stewart, Graeme Douglas

    Recent advances in particle accelerators have increased the demands being placed on detectors. Novel detector designs are being implemented in many different areas including, for example, high luminosity experiments at the LHC or at next generation synchrotrons. The purpose of this thesis was to characterise some of these novel detectors. The first of the new detector types is called a 3D detector. This design was first proposed by Parker, Kenney and Segal (1997). In this design, doped electrodes are created that extend through the silicon substrate. When compared to a traditional photodiode with electrodes on the opposing surfaces, the 3D design can combine a reasonable detector thickness with a small electrode spacing resulting in fast charge collection and limited charge sharing. The small electrode spacing leads to the detectors having lower depletion voltages. This, combined with the fast collection time, makes 3D detectors a candidate for radiation hard applications. These applications include the upgra...

  19. Metal-semiconductor, composite radiation detectors

    International Nuclear Information System (INIS)

    Orvis, W.J.; Yee, J.H.; Fuess, D.A.

    1991-12-01

    In 1989, Naruse and Hatayama of Toshiba published a design for an increased efficiency x-ray detector. The design increased the efficiency of a semiconductor detector by interspersing layers of high-z metal within it. Semiconductors such as silicon make good, high-resolution radiation detectors, but they have low efficiency because they are low-z materials (z = 14). High-z metals, on the other hand, are good absorbers of high-energy photons. By interspersing high-z metal layers with semiconductor layers, Naruse and Hatayama combined the high absorption efficiency of the high-z metals with good detection capabilities of a semiconductor. This project is an attempt to use the same design to produce a high- efficiency gamma ray detector. By their nature, gamma rays require thicker metal layers to efficiently absorb them. These thicker layers change the behavior of the detector by reducing the resolution, compared to a solid state detector, and shifting the photopeak by a predictable amount. During the last year, we have modeled parts of the detector and have nearly completed a prototype device. 2 refs

  20. Bi-layer plate-type acoustic metamaterials with Willis coupling

    Science.gov (United States)

    Ma, Fuyin; Huang, Meng; Xu, Yicai; Wu, Jiu Hui

    2018-01-01

    Dynamic effective negative parameters are principal to the representation of the physical properties of metamaterials. In this paper, a bi-layer plate-type unit was proposed with both a negative mass density and a negative bulk modulus; moreover, through analysis of these bi-layer structures, some important problems about acoustic metamaterials were studied. First, dynamic effective mass densities and the bulk modulus of the bi-layer plate-type acoustic structure were clarified through both the direct and the retrieval methods, and, in addition, the intrinsic relationship between the sound transmission (absorption) characteristics and the effective parameters was analyzed. Furthermore, the properties of dynamic effective parameters for an asymmetric bi-layer acoustic structure were further considered through an analysis of experimental data, and the modified effective parameters were then obtained through consideration of the Willis coupling in the asymmetric passive system. In addition, by taking both the clamped and the periodic boundary conditions into consideration in the bi-layer plate-type acoustic system, new perspectives were presented for study on the effective parameters and sound insulation properties in the range below the cut-off frequency. The special acoustic properties established by these effective parameters could enrich our knowledge and provide guidance for the design and installation of acoustic metamaterial structures in future sound engineering practice.

  1. Performance of irradiated silicon microstrip detectors

    International Nuclear Information System (INIS)

    Catacchini, E.; Civinini, C.; D'Alessandro, R.; Focardi, E.; Lenzi, M.; Meschini, M.; Parrini, G.; Pieri, M.

    1999-01-01

    Silicon microstrip devices to be installed in Large Hadron Collider (LHC) tracking detectors will have to operate in a high radiation environment. We report on performance studies of silicon microstrip detectors irradiated with neutrons or protons, up to fluences comparable to the first ten years of running at LHC. Obtained results show that irradiated detectors can still be operated with satisfactory signal-to-noise ratio,and in the case of inhomogeneously type inverted detector a very good position resolution is achieved regardless of the zone crossed by the particle

  2. Transient response of self-powered neutron detectors

    International Nuclear Information System (INIS)

    Boeck, H.; Gebureck, P.; Stegemann, D.

    The behaviour of self-powered neutron detectors with Co, Er, Hf and Pt emitters was investigated during reactor square wave and pulse operation. The detector's response was compared with the current of an excore ionization chamber. Characteristical deviations from linearity were observed with all detectors at fast reactor periods. The exact cause of these deviations is not yet fully understood but several possibilities for the nonlinear behaviour of self-powered neutron detectors are outlined. (author)

  3. Birth seasonality in Korean Prader-Willi syndrome with chromosome 15 microdeletion

    Directory of Open Access Journals (Sweden)

    Aram Yang

    2015-03-01

    Full Text Available PurposePrader-Willi syndrome (PWS is a well-known genetic disorder, and microdeletion on chromosome 15 is the most common causal mechanism. Several previous studies have suggested that various environmental factors might be related to the pathogenesis of microdeletion in PWS. In this study, we investigated birth seasonality in Korean PWS.MethodsA total of 211 PWS patients born from 1980 to 2014 were diagnosed by methylation polymerase chain reaction at Samsung Medical Center. Of the 211 patients, 138 were born from 2000-2013. Among them, the 74 patients of a deletion group and the 22 patients of a maternal uniparental disomy (UPD group were compared with general populations born from 2000 using the Walter and Elwood method and cosinor analysis.ResultsThere was no statistical significance in seasonal variation in births of the total 211 patients with PWS (χ2=7.2522, P=0.2982. However, a significant difference was found in the monthly variation between PWS with the deletion group and the at-risk general population (P<0.05. In the cosinor model, the peak month of birth for PWS patients in the deletion group was January, while the nadir occurred in July, with statistical significance (amplitude=0.23, phase=1.2, low point=7.2. The UPD group showed the peak birth month in spring; however, this result was not statistically significant (χ2=3.39, P=0.1836.ConclusionCorrelation with birth seasonality was identified in a deletion group of Korean PWS patients. Further studies are required to identify the mechanism related to seasonal effects of environmental factors on microdeletion on chromosome 15.

  4. Rotating detectors and Mach's principle

    International Nuclear Information System (INIS)

    Paola, R.D.M. de; Svaiter, N.F.

    2000-08-01

    In this work we consider a quantum version of Newton s bucket experiment in a fl;at spacetime: we take an Unruh-DeWitt detector in interaction with a real massless scalar field. We calculate the detector's excitation rate when it is uniformly rotating around some fixed point and the field is prepared in the Minkowski vacuum and also when the detector is inertial and the field is in the Trocheries-Takeno vacuum state. These results are compared and the relations with Mach's principle are discussed. (author)

  5. A Figure-of-Merit for Beta Cell Detector Characterization

    Energy Technology Data Exchange (ETDEWEB)

    Foxe, Michael P. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Miller, Brian W. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Suarez, Rey [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hayes, James C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2015-09-02

    In order to decrease the minimum detectable activities (MDAs) of beta-gamma radioxenon detectors, it is important to increase the ability to resolve the individual isotopes. One proposed method for doing this is to increase the energy resolution of the beta cell through the use of silicon detectors. While silicon detectors can improve the energy resolution, it is accompanied with a decrease in detection efficiency compared to plastic scintillator beta cells. Due to the uncertainty on the impact of the competing variables, we have developed a figure-of-merit (FOM) capable of determining the impact of detector parameters on the MDAs. By utilizing the FOM to analyze different detectors, we are able to directly compare current and future detectors and estimate their impact on the radioxenon MDAs.

  6. PET scan perfusion imaging in the Prader-Willi syndrome: new insights into the psychiatric and social disturbances

    International Nuclear Information System (INIS)

    Mantoulan, C.; Payoux, P.; Mantoulan, C.; Diene, G.; Glattard, M.; Molinas, C.; Tauber, M.; Payoux, P.; Sevely, A.; Glattard, M.; Roge, B.; Molinas, C.; Tauber, M.; Zilbovicius, M.; Celsis, P.; Celsis, P.

    2011-01-01

    The Prader-Willi syndrome (PWS), a rare multisystem genetic disease, leads to severe disabilities, such as morbid obesity, endocrine dysfunctions, psychiatric disorders, and social disturbances. We explored the whole brain of patients with PWS to detect abnormalities that might explain the behavioral and social disturbances, as well as the psychiatric disorders of these patients. Nine patients with PWS (six males, three females; mean age 16.4 years) underwent a positron emission tomography (PET) scan with H(2)(15)O as a tracer to measure regional cerebral blood flow (rCBF). The images were compared with those acquired from nine controls (six males, three females; mean age 21.2 years). A morphologic magnetic resonance imaging (MRI) was also performed in PWS patients, and their cognitive and behavioral skills were assessed with Wechsler Intelligence Scale for Children III and the Child Behavior Check List (CBCL). The MRI images showed no evident anatomic abnormalities, whereas PET scans revealed hypo-perfused brain regions in PWS patients compared with controls, particularly in the anterior cingulum and superior temporal regions. We observed a significant relationship (P≤0.05) between rCBF in the hypo-perfused regions and CBCL scores. The functional consequences of these perfusion abnormalities in specific brain regions might explain the behavioral and social problems observed in these individuals. (authors)

  7. Medication Trials for Hyperphagia and Food-Related Behaviors in Prader–Willi Syndrome

    Directory of Open Access Journals (Sweden)

    Jennifer L. Miller

    2015-06-01

    Full Text Available Prader-Willi syndrome (PWS is a neurodevelopmental disorder caused by the absence of paternally expressed, imprinted genes on chromosome 15q11-13. Individuals with PWS characteristically have poor feeding and lack of appetite in infancy, followed by the development of weight gain and then uncontrolled appetite and lack of satiety, sometime after the age of two. The overwhelming drive to eat is coupled with reduced energy expenditure and decreased caloric requirements, thus, individuals with PWS will become severely obese unless their food intake is strictly controlled. The mechanisms underlying hyperphagia in PWS remain incompletely understood, and to date no drugs have proven effective in controlling appetite. However, clinical trials have started for several medications, which may provide therapeutic options for those with PWS. These medication trials may also provide insight into potential treatments for obesity in the general population. Ideally, these treatments will help alleviate the complex metabolic issues that are part of this syndrome.

  8. Puzzle Pieces: Neural Structure and Function in Prader-Willi Syndrome

    Science.gov (United States)

    Manning, Katherine E.; Holland, Anthony J.

    2015-01-01

    Prader-Willi syndrome (PWS) is a neurodevelopmental disorder of genomic imprinting, presenting with a behavioural phenotype encompassing hyperphagia, intellectual disability, social and behavioural difficulties, and propensity to psychiatric illness. Research has tended to focus on the cognitive and behavioural investigation of these features, and, with the exception of eating behaviour, the neural physiology is currently less well understood. A systematic review was undertaken to explore findings relating to neural structure and function in PWS, using search terms designed to encompass all published articles concerning both in vivo and post-mortem studies of neural structure and function in PWS. This supported the general paucity of research in this area, with many articles reporting case studies and qualitative descriptions or focusing solely on the overeating behaviour, although a number of systematic investigations were also identified. Research to date implicates a combination of subcortical and higher order structures in PWS, including those involved in processing reward, motivation, affect and higher order cognitive functions, with both anatomical and functional investigations indicating abnormalities. It appears likely that PWS involves aberrant activity across distributed neural networks. The characterisation of neural structure and function warrants both replication and further systematic study. PMID:28943631

  9. Puzzle Pieces: Neural Structure and Function in Prader-Willi Syndrome

    Directory of Open Access Journals (Sweden)

    Katherine E. Manning

    2015-12-01

    Full Text Available Prader-Willi syndrome (PWS is a neurodevelopmental disorder of genomic imprinting, presenting with a behavioural phenotype encompassing hyperphagia, intellectual disability, social and behavioural difficulties, and propensity to psychiatric illness. Research has tended to focus on the cognitive and behavioural investigation of these features, and, with the exception of eating behaviour, the neural physiology is currently less well understood. A systematic review was undertaken to explore findings relating to neural structure and function in PWS, using search terms designed to encompass all published articles concerning both in vivo and post-mortem studies of neural structure and function in PWS. This supported the general paucity of research in this area, with many articles reporting case studies and qualitative descriptions or focusing solely on the overeating behaviour, although a number of systematic investigations were also identified. Research to date implicates a combination of subcortical and higher order structures in PWS, including those involved in processing reward, motivation, affect and higher order cognitive functions, with both anatomical and functional investigations indicating abnormalities. It appears likely that PWS involves aberrant activity across distributed neural networks. The characterisation of neural structure and function warrants both replication and further systematic study.

  10. Comparison of natural and synthetic diamond X-ray detectors.

    Science.gov (United States)

    Lansley, S P; Betzel, G T; Metcalfe, P; Reinisch, L; Meyer, J

    2010-12-01

    Diamond detectors are particularly well suited for dosimetry applications in radiotherapy for reasons including near-tissue equivalence and high-spatial resolution resulting from small sensitive volumes. However, these detectors have not become commonplace due to high cost and poor availability arising from the need for high-quality diamond. We have fabricated relatively cheap detectors from commercially-available synthetic diamond fabricated using chemical vapour deposition. Here, we present a comparison of one of these detectors with the only commercially-available diamond-based detector (which uses a natural diamond crystal). Parameters such as the energy dependence and linearity of charge with dose were investigated at orthovoltage energies (50-250 kV), and dose-rate dependence of charge at linear accelerator energy (6 MV). The energy dependence of a synthetic diamond detector was similar to that of the natural diamond detector, albeit with slightly less variation across the energy range. Both detectors displayed a linear response with dose (at 100 kV) over the limited dose range used. The sensitivity of the synthetic diamond detector was 302 nC/Gy, compared to 294 nC/Gy measured for the natural diamond detector; however, this was obtained with a bias of 246.50 V compared to a bias of 61.75 V used for the natural diamond detector. The natural diamond detector exhibited a greater dependency on dose-rate than the synthetic diamond detector. Overall, the synthetic diamond detector performed well in comparison to the natural diamond detector.

  11. Relationship between white matter hyperintensities volume and the circle of Willis configurations in patients with carotid artery pathology.

    Science.gov (United States)

    Saba, Luca; Sanfilippo, Roberto; Porcu, Michele; Lucatelli, Pierleone; Montisci, Roberto; Zaccagna, Fulvio; Suri, Jasjit S; Anzidei, Michele; Wintermark, Max

    2017-04-01

    We aimed to assess if there is a difference of distribution and volume of white matter hyperintensities (WMH) in the brain according to the Circle of Willis (CoW) configuration in patients with carotid artery pathology. One-hundred consecutive patients (79 males, 21 females; mean age 70 years; age range 46-84 years) that underwent brain MRI before carotid endarterectomy (CEA) were included. FLAIR-WMH lesion volume was performed using a semi-automated segmentation technique and the status of the circle of Willis was assessed by two neuroradiologists in consensus. We found a prevalence of 55% of variants in the CoW configuration; 22 cases had one variants (40%); 25 cases had two variants (45.45%) and 8 cases showed 3 variants (14.55%). The configuration that was associated with the biggest WMH volume and number of lesions was the A1+PcoA+PcoA. The PcoA variants were the most prevalent and there was no statistically significant difference in number of lesions and WMH for each vascular territory assessed and the same results were found for AcoA and A1 variants. Results of our study suggest that the more common CoW variants are not associated with the presence of an increased WMH or number of lesions whereas uncommon configurations, in particular when 2 or more segment are missing increase the WMH volume and number of lesions. The WHM volume of the MCA territory seems to be more affected by the CoW configuration. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Relationship between white matter hyperintensities volume and the circle of Willis configurations in patients with carotid artery pathology

    International Nuclear Information System (INIS)

    Saba, Luca; Sanfilippo, Roberto; Porcu, Michele; Lucatelli, Pierleone; Montisci, Roberto; Zaccagna, Fulvio; Suri, Jasjit S.; Anzidei, Michele; Wintermark, Max

    2017-01-01

    Purpose: We aimed to assess if there is a difference of distribution and volume of white matter hyperintensities (WMH) in the brain according to the Circle of Willis (CoW) configuration in patients with carotid artery pathology. Material and methods: One-hundred consecutive patients (79 males, 21 females; mean age 70 years; age range 46–84 years) that underwent brain MRI before carotid endarterectomy (CEA) were included. FLAIR-WMH lesion volume was performed using a semi-automated segmentation technique and the status of the circle of Willis was assessed by two neuroradiologists in consensus. Results: We found a prevalence of 55% of variants in the CoW configuration; 22 cases had one variants (40%); 25 cases had two variants (45.45%) and 8 cases showed 3 variants (14.55%). The configuration that was associated with the biggest WMH volume and number of lesions was the A1 + PcoA + PcoA. The PcoA variants were the most prevalent and there was no statistically significant difference in number of lesions and WMH for each vascular territory assessed and the same results were found for AcoA and A1 variants. Conclusion: Results of our study suggest that the more common CoW variants are not associated with the presence of an increased WMH or number of lesions whereas uncommon configurations, in particular when 2 or more segment are missing increase the WMH volume and number of lesions. The WHM volume of the MCA territory seems to be more affected by the CoW configuration.

  13. Relationship between white matter hyperintensities volume and the circle of Willis configurations in patients with carotid artery pathology

    Energy Technology Data Exchange (ETDEWEB)

    Saba, Luca, E-mail: lucasaba@tiscali.it [Department of Radiology, Azienda Ospedaliero Universitaria (A.O.U.), di Cagliari – Polo di Monserrato, s.s. 554 Monserrato, Cagliari 09045 (Italy); Sanfilippo, Roberto [Department of Vascular Surgery, Azienda Ospedaliero Universitaria (A.O.U.), di Cagliari – Polo di Monserrato, s.s. 554 Monserrato, Cagliari 09045 (Italy); Porcu, Michele [Department of Radiology, Azienda Ospedaliero Universitaria (A.O.U.), di Cagliari – Polo di Monserrato, s.s. 554 Monserrato, Cagliari 09045 (Italy); Lucatelli, Pierleone [Department of Radiology, University la Sapienza, Rome (Italy); Montisci, Roberto [Department of Vascular Surgery, Azienda Ospedaliero Universitaria (A.O.U.), di Cagliari – Polo di Monserrato, s.s. 554 Monserrato, Cagliari 09045 (Italy); Zaccagna, Fulvio [Department of Radiology, University la Sapienza, Rome (Italy); Suri, Jasjit S. [Monitoring and Diagnostic Division, AtheroPoint, Roseville, CA (United States); Point-of-Care Devices, Global Biomedical Technologies, Inc., Roseville, CA (United States); Department of Electrical Engineering, University of Idaho (Affl.), ID (United States); Anzidei, Michele [Department of Radiology, University la Sapienza, Rome (Italy); Wintermark, Max [Department of Radiology, Stanford University (United States)

    2017-04-15

    Purpose: We aimed to assess if there is a difference of distribution and volume of white matter hyperintensities (WMH) in the brain according to the Circle of Willis (CoW) configuration in patients with carotid artery pathology. Material and methods: One-hundred consecutive patients (79 males, 21 females; mean age 70 years; age range 46–84 years) that underwent brain MRI before carotid endarterectomy (CEA) were included. FLAIR-WMH lesion volume was performed using a semi-automated segmentation technique and the status of the circle of Willis was assessed by two neuroradiologists in consensus. Results: We found a prevalence of 55% of variants in the CoW configuration; 22 cases had one variants (40%); 25 cases had two variants (45.45%) and 8 cases showed 3 variants (14.55%). The configuration that was associated with the biggest WMH volume and number of lesions was the A1 + PcoA + PcoA. The PcoA variants were the most prevalent and there was no statistically significant difference in number of lesions and WMH for each vascular territory assessed and the same results were found for AcoA and A1 variants. Conclusion: Results of our study suggest that the more common CoW variants are not associated with the presence of an increased WMH or number of lesions whereas uncommon configurations, in particular when 2 or more segment are missing increase the WMH volume and number of lesions. The WHM volume of the MCA territory seems to be more affected by the CoW configuration.

  14. Atmospheric fluxes and energy spectra of positive and negative muons from Monte-Carlo simulations

    International Nuclear Information System (INIS)

    Vulpescu, B.; Brancus, I.M.; Badea, A.F.; Duma, M.; Bozdog, H.; Petru, M.; Rebel, H.; Weintz, J.; Mathes, H.J.; Haungs, A.; Roth, M.

    1999-01-01

    Cosmic ray muons observed with detectors placed at the ground level originate from the decay of mesons produced by interactions of high energy cosmic ray primaries with air nuclei, mainly due to the decay of charged pions and kaons, processes which lead also to the production of atmospheric neutrinos. Prompted by recent accurate measurements of the charge ratio of atmospheric muons, the flux and energy spectra of positive and negative muons have been studied on the basis of Monte-Carlo simulations (CORSIKA) of the EAS development, using the GHEISHA and VENUS model as generators. The results have been analysed and compared with data under the aspect of their sensitivity to details of the hadronic interaction, in particular in the 3 GeV/n - 20 TeV/n region. The muon charge ratio proves to be a sensitive test quantity for the production model and propagation and it exhibits peculiar features at low energies (< 1 GeV). Results are shown, from magnetic spectrometer experiments in the difficult region of low momenta as well as the precise values obtained with the WILLI detector by observing the lifetime of negative muons stopped in material. The CORSIKA predictions on the charge ratio show a drop below 1 for very low muon momentum and needs further experimental investigations. The EAST-WEST effect is characteristic for low muon momenta and is well reproduced by simulations. The WILLI detector is planned to be developed in a new configuration, being able to investigate with high accuracy the muon charge ratio at different zenithal and azimuthal directions. (authors)

  15. The LiC detector toy program

    International Nuclear Information System (INIS)

    Regler, Meinhard; Valentan, Manfred; Fruehwirth, Rudolf

    2007-01-01

    This note describes the 'LiC Detector Toy' ('LiC' for Linear Collider) software tool which has been developed for detector design studies, aiming at investigating the resolution of reconstructed track parameters for the purpose of comparing and optimizing various detector setups. It consists of a simplified simulation of the detector measurements, taking into account multiple scattering, followed by full single track reconstruction using the Kalman filter. The tool is written in MATLAB and may be installed on a laptop. It can easily be used as a black-box tool by non-experts, but also adapted to individual needs

  16. Mosaicism for maternal uniparental disomy 15 in a boy with some clinical features of Prader-Willi syndrome.

    Science.gov (United States)

    Zilina, Olga; Kahre, Tiina; Talvik, Inga; Oiglane-Shlik, Eve; Tillmann, Vallo; Ounap, Katrin

    2014-01-01

    Prader-Willi syndrome (PWS) is caused by the lack of paternal expression of imprinted genes in the human chromosomal region 15q11.2-q13.2, which can be due to an interstitial deletion at 15q11.2-q13 of paternal origin (65-75%), maternal uniparental disomy (matUPD) of chromosome 15 (20-30%), or an imprinting defect (1-3%). The majority of PWS-associated matUPD15 cases represent a complete heterodisomy of chromosome 15 or a mixture of hetero- and isodisomic regions across the chromosome 15. Pure maternal isodisomy is observed in only a few matUPD15 patients. Here we report a case of an 18-year-old boy with some clinical features of Prader-Willi syndrome, such as overweight, muscular hypotonia, facial dysmorphism and psychiatric problems, but there was no reason to suspect PWS in the patient based solely on the phenotype estimation. However, chromosomal microarray analysis (CMA) revealed mosaic loss of heterozygosity of the entire chromosome 15. Methylation-specific multiplex ligation-dependant probe amplification (MS-MLPA) analysis showed hypermethylation of the SNRPN and NDN genes in the PWS/AS critical region of chromosome 15 in this patient. Taking into consideration the MS-MLPA results and the presence of PWS features in the patient, we concluded that it was matUPD15, although the patient's parents were not enrolled in the study. According to CMA and karyotyping, no trisomic or monosomic cells were present. To the best of our knowledge, only two PWS cases with mosaic maternal isodisomy 15 and without trisomic/monosomic cell lines have been reported so far. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  17. Scintillation detectors of Alborz-I experiment

    International Nuclear Information System (INIS)

    Pezeshkian, Yousef; Bahmanabadi, Mahmud; Abbasian Motlagh, Mehdi; Rezaie, Masume

    2015-01-01

    A new air shower experiment of the Alborz Observatory, Alborz-I, located at the Sharif University of Technology, Iran, will be constructed in near future. An area of about 30×40 m 2 will be covered by 20 plastic scintillation detectors (each with an area of 50×50 cm 2 ). A series of experiments have been performed to optimize the height of light enclosures of the detectors for this array and the results have been compared to an extended code simulation of these detectors. Operational parameters of the detector obtained by this code are cross checked by the Geant4 simulation. There is a good agreement between the extended-code and Geant4 simulations. We also present further discussions on the detector characteristics, which can be applicable for all scintillation detectors with a similar configuration

  18. Radiation detectors

    International Nuclear Information System (INIS)

    2013-01-01

    This sixth chapter presents the operational principles of the radiation detectors; detection using photographic emulsions; thermoluminescent detectors; gas detectors; scintillation detectors; liquid scintillation detectors; detectors using semiconductor materials; calibration of detectors; Bragg-Gray theory; measurement chain and uncertainties associated to measurements

  19. WE-G-204-05: Relative Object Detectability Evaluation of a New High Resolution A-Se Direct Detection System Compared to Indirect Micro-Angiographic Fluoroscopic (MAF) Detectors

    International Nuclear Information System (INIS)

    Russ, M; Nagesh, S Setlur; Ionita, C; Bednarek, D; Rudin, S; Scott, C; Karim, K

    2015-01-01

    Purpose: To evaluate the task specific imaging performance of a new 25µm pixel pitch, 1000µm thick amorphous selenium direct detection system with CMOS readout for typical angiographic exposure parameters using the relative object detectability (ROD) metric. Methods: The ROD metric uses a simulated object function weighted at each spatial frequency by the detectors’ detective quantum efficiency (DQE), which is an intrinsic performance metric. For this study, the simulated objects were aluminum spheres of varying diameter (0.05–0.6mm). The weighted object function is then integrated over the full range of detectable frequencies inherent to each detector, and a ratio is taken of the resulting value for two detectors. The DQE for the 25µm detector was obtained from a simulation of a proposed a-Se detector using an exposure of 200µR for a 50keV x-ray beam. This a-Se detector was compared to two microangiographic fluoroscope (MAF) detectors [the MAF-CCD with pixel size of 35µm and Nyquist frequency of 14.2 cycles/mm and the MAF-CMOS with pixel size of 75µm and Nyquist frequency of 6.6 cycles/mm] and a standard flat-panel detector (FPD with pixel size of 194µm and Nyquist frequency of 2.5cycles/mm). Results: ROD calculations indicated vastly superior performance by the a-Se detector in imaging small aluminum spheres. For the 50µm diameter sphere, the ROD values for the a-Se detector compared to the MAF-CCD, the MAF-CMOS, and the FPD were 7.3, 9.3 and 58, respectively. Detector performance in the low frequency regime was dictated by each detector’s DQE(0) value. Conclusion: The a-Se with CMOS readout is unique and appears to have distinctive advantages of incomparable high resolution, low noise, no readout lag, and expandable design. The a-Se direct detection system will be a powerful imaging tool in angiography, with potential break-through applications in diagnosis and treatment of neuro-vascular disease. Supported by NIH Grant: 2R01EB002873 and an

  20. WE-G-204-05: Relative Object Detectability Evaluation of a New High Resolution A-Se Direct Detection System Compared to Indirect Micro-Angiographic Fluoroscopic (MAF) Detectors

    Energy Technology Data Exchange (ETDEWEB)

    Russ, M; Nagesh, S Setlur; Ionita, C; Bednarek, D; Rudin, S [Toshiba Stroke and Vascular Research Center, University at Buffalo (SUNY), Buffalo, NY (United States); Scott, C; Karim, K [University of Waterloo, Waterloo, ON (Canada)

    2015-06-15

    Purpose: To evaluate the task specific imaging performance of a new 25µm pixel pitch, 1000µm thick amorphous selenium direct detection system with CMOS readout for typical angiographic exposure parameters using the relative object detectability (ROD) metric. Methods: The ROD metric uses a simulated object function weighted at each spatial frequency by the detectors’ detective quantum efficiency (DQE), which is an intrinsic performance metric. For this study, the simulated objects were aluminum spheres of varying diameter (0.05–0.6mm). The weighted object function is then integrated over the full range of detectable frequencies inherent to each detector, and a ratio is taken of the resulting value for two detectors. The DQE for the 25µm detector was obtained from a simulation of a proposed a-Se detector using an exposure of 200µR for a 50keV x-ray beam. This a-Se detector was compared to two microangiographic fluoroscope (MAF) detectors [the MAF-CCD with pixel size of 35µm and Nyquist frequency of 14.2 cycles/mm and the MAF-CMOS with pixel size of 75µm and Nyquist frequency of 6.6 cycles/mm] and a standard flat-panel detector (FPD with pixel size of 194µm and Nyquist frequency of 2.5cycles/mm). Results: ROD calculations indicated vastly superior performance by the a-Se detector in imaging small aluminum spheres. For the 50µm diameter sphere, the ROD values for the a-Se detector compared to the MAF-CCD, the MAF-CMOS, and the FPD were 7.3, 9.3 and 58, respectively. Detector performance in the low frequency regime was dictated by each detector’s DQE(0) value. Conclusion: The a-Se with CMOS readout is unique and appears to have distinctive advantages of incomparable high resolution, low noise, no readout lag, and expandable design. The a-Se direct detection system will be a powerful imaging tool in angiography, with potential break-through applications in diagnosis and treatment of neuro-vascular disease. Supported by NIH Grant: 2R01EB002873 and an

  1. Quantitative comparison using Generalized Relative Object Detectability (G-ROD) metrics of an amorphous selenium detector with high resolution Microangiographic Fluoroscopes (MAF) and standard flat panel detectors (FPD).

    Science.gov (United States)

    Russ, M; Shankar, A; Jain, A; Setlur Nagesh, S V; Ionita, C N; Scott, C; Karim, K S; Bednarek, D R; Rudin, S

    2016-02-27

    A novel amorphous selenium (a-Se) direct detector with CMOS readout has been designed, and relative detector performance investigated. The detector features include a 25 μ m pixel pitch, and 1000 μ m thick a-Se layer operating at 10V/ μ m bias field. A simulated detector DQE was determined, and used in comparative calculations of the Relative Object Detectability (ROD) family of prewhitening matched-filter (PWMF) observer and non-prewhitening matched filter (NPWMF) observer model metrics to gauge a-Se detector performance against existing high resolution micro-angiographic fluoroscopic (MAF) detectors and a standard flat panel detector (FPD). The PWMF-ROD or ROD metric compares two x-ray imaging detectors in their relative abilities in imaging a given object by taking the integral over spatial frequencies of the Fourier transform of the detector DQE weighted by an object function, divided by the comparable integral for a different detector. The generalized-ROD (G-ROD) metric incorporates clinically relevant parameters (focal-spot size, magnification, and scatter) to show the degradation in imaging performance for detectors that are part of an imaging chain. Preliminary ROD calculations using simulated spheres as the object predicted superior imaging performance by the a-Se detector as compared to existing detectors. New PWMF-G-ROD and NPWMF-G-ROD results still indicate better performance by the a-Se detector in an imaging chain over all sphere sizes for various focal spot sizes and magnifications, although a-Se performance advantages were degraded by focal spot blurring. Nevertheless, the a-Se technology has great potential to provide breakthrough abilities such as visualization of fine details including of neuro-vascular perforator vessels and of small vascular devices.

  2. Severe Short Stature in an Adolescent Male with Prader-Willi Syndrome and Congenital Adrenal Hyperplasia: A Therapeutic Conundrum

    Directory of Open Access Journals (Sweden)

    Meredith Wasserman

    2017-01-01

    Full Text Available Congenital adrenal hyperplasia (CAH due to 21-hydroxylase deficiency results in excess androgen production which can lead to early epiphyseal fusion and short stature. Prader-Willi syndrome (PWS is a genetic disorder resulting from a defect on chromosome 15 due to paternal deletion, maternal uniparental disomy, or imprinting defect. Ninety percent of patients with PWS have short stature. In this article we report a patient with simple-virilizing CAH and PWS who was overtreated with glucocorticoids for CAH and not supplemented with growth hormone for PWS, resulting in a significantly short adult height.

  3. Testing 144- and 256-crystal BGO block detectors

    International Nuclear Information System (INIS)

    Rogers, J.G.; Nutt, R.; Andreaco, M.; Williams, C.W.

    1994-01-01

    New block detectors have been fabricated incorporating large numbers of small crystals. The authors evaluate and compare the performance of the new detectors with a standard 64-crystal block detector from Siemens-CTI. The new detectors demonstrate greatly improved imaging capability for 511 keV gamma rays. Future PET tomographs incorporating such detectors should produce substantially better volume images with little increase in tomograph manufacturing costs. The detectors will require a new type of automatic calibration procedure. Various such procedures have been tested and are discussed. A technique using higher energy gamma rays has shown special promise

  4. Comparison of phoswich and ARSA-type detectors for radioxenon measurements

    International Nuclear Information System (INIS)

    Ward, R.M.; Biegalski, S.R.F.; Hennig, W.

    2009-01-01

    The monitoring of atmospheric radioxenon to ensure compliance with the Comprehensive Nuclear Test Ban Treaty (CTBT) has driven the development of improved detectors for measuring xenon, including the development of a phoswich detector. This detector uses only one PMT to detect β-γ coincidence, thus greatly reducing the bulk and electronics of the detector in comparison to the ARSA-type detector. In this experiment, 135 Xe was produced through neutron activation and a phoswich detector was used to attain spectra from the gas. These results were compared to similar results from an ARSA-type β-γ coincidence spectrum. The spectral characteristics and resolution were compared for the coincidence and beta spectra. Using these metrics, the overall performance of the phoswich detector for β-γ coincidence of radioxenon was evaluated. (author)

  5. Ionization detector

    International Nuclear Information System (INIS)

    Steele, D.S.

    1987-01-01

    An ionization detector having an array of detectors has, for example, grounding pads positioned in the spaces between some detectors (data detectors) and other detectors (reference detectors). The grounding pads are kept at zero electric potential, i.e. grounded. The grounding serves to drain away electrons and thereby prevent an unwanted accumulation of charge in the spaces, and cause the electric field lines to be more perpendicular to the detectors in regions near the grounding pads. Alternatively, no empty space is provided there being additional, grounded, detectors provided between the data and reference detectors. (author)

  6. Development of neutron detectors for neutron scattering experiments

    Energy Technology Data Exchange (ETDEWEB)

    Moon, Myungkook; Kim, Jongyul; Kim, Jeong ho; Lee, Suhyun [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Lee, Changhwy [Korea Research Institute of Ships and Ocean Engineering, Daejeon (Korea, Republic of)

    2015-10-15

    Various kinds of detectors are used in accordance with the experimental purpose, such as zero dimensional detector, 1-D or 2-D position-sensitive detectors. Most of neutron detectors use He-3 gas because of its high neutron sensitivity. Since the He-3 supply shortage took place in early 2010, various He-3 alternative detectors have been developed even for the other neutron application. We have developed a new type alternative detector on the basis of He-3 detector technology. Although B- 10 has less neutron detection efficiency compared with He-3, it can be covered by the use of multiple B-10 layers. In this presentation, we would like to introduce the neutron detectors under development and developed detectors. Various types of detector were successfully developed and result of the technical test performance is promising. Even though the detection efficiency of the B-10 detector lower than He-3 one, the continuous research and development is needed for currently not available He-3.

  7. High circulating ghrelin: a potential cause for hyperphagia and obesity in prader-willi syndrome

    DEFF Research Database (Denmark)

    DelParigi, Angelo; Tschöp, Matthias; Heiman, Mark L

    2002-01-01

    Prader-Willi syndrome (PWS) is a genetic disorder occurring in 1 of 10,000-16,000 live births and is characterized by excessive appetite with progressive massive obesity as well as short stature and mental retardation. Most patients have GH deficiency and hypogonadotropic hypogonadism. The causes...... of the hyperphagia and abnormal GH secretion are unknown. To determine whether ghrelin, a novel GH secretagogue with orexigenic properties, is elevated in PWS, we measured fasting plasma ghrelin concentration; body composition (dual-energy x-ray absorptiometry); and subjective ratings of hunger (visual analog scale......) in seven subjects (6 males and 1 female; age, 26 +/- 7 yr; body fat, 39 +/- 11%, mean +/- SD) with PWS (diagnosis confirmed by genetic test) and 30 healthy subjects (reference population, 15 males and 15 females; age, 32 +/- 7 yr; body fat, 36 +/- 11%) fasted overnight. All subjects were weight stable...

  8. Self-Powered Neutron and Gamma Detectors for In-Core Measurements

    International Nuclear Information System (INIS)

    Strindehag, O.

    1971-11-01

    The performance of various types of self-powered neutron and gamma detectors intended for control and power distribution measurements in water cooled reactors is discussed. The self-powered detectors are compared with other types of in-core detectors and attention is paid to such properties as neutron and gamma sensitivity, high-temperature performance, burn-up rate and time of response. Also treated are the advantages and disadvantages of using gamma detector data for power distribution calculations instead of data from neutron detectors. With regard to neutron-sensitive detectors, results from several long-term experiments with vanadium and cobalt detectors are presented. The results include reliability and stability data for these two detector types and the Co build-up in cobalt detectors. Experimental results which reveal the fast response of cobalt detectors are presented, and the use of cobalt detectors in reactor safety systems is discussed. Experience of the design and installation of complete flux probes, electronic units and data processing systems for power reactors is reported. The investigation of gamma-sensitive detectors includes detectors with emitters of lead, zirconium, magnesium and Inconel. Measured gamma sensitivities from calibrations both in a reactor and in a gamma cell are given, and the signal levels of self-powered neutron and gamma detectors when applied to power reactors are compared

  9. Self-Powered Neutron and Gamma Detectors for In-Core Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Strindehag, O

    1971-11-15

    The performance of various types of self-powered neutron and gamma detectors intended for control and power distribution measurements in water cooled reactors is discussed. The self-powered detectors are compared with other types of in-core detectors and attention is paid to such properties as neutron and gamma sensitivity, high-temperature performance, burn-up rate and time of response. Also treated are the advantages and disadvantages of using gamma detector data for power distribution calculations instead of data from neutron detectors. With regard to neutron-sensitive detectors, results from several long-term experiments with vanadium and cobalt detectors are presented. The results include reliability and stability data for these two detector types and the Co build-up in cobalt detectors. Experimental results which reveal the fast response of cobalt detectors are presented, and the use of cobalt detectors in reactor safety systems is discussed. Experience of the design and installation of complete flux probes, electronic units and data processing systems for power reactors is reported. The investigation of gamma-sensitive detectors includes detectors with emitters of lead, zirconium, magnesium and Inconel. Measured gamma sensitivities from calibrations both in a reactor and in a gamma cell are given, and the signal levels of self-powered neutron and gamma detectors when applied to power reactors are compared

  10. A detector for tomography by Compton scattering at 900 and tomography apparatus comprising such detector

    International Nuclear Information System (INIS)

    Ricodeau, Jean.

    1981-01-01

    The present invention concerns a detector for tomography by Compton scattering at 90 0 . The difference between this detector and those currently used previously lies in the fact that the collection aperture of the radiation at normal angle to the incident beam is large and can reach 180 0 and even more. This fact allows to collect an important part of the scattered radiation. A good image quality is obtained with low radiation doses delivered to the body as compared to previous techniques. This detector can be operated in analogical mode which presents the advantage to be faster and easier to realize [fr

  11. Obesity and Prader-Willi Syndrome Affect Heart Rate Recovery from Dynamic Resistance Exercise in Youth

    Directory of Open Access Journals (Sweden)

    Diobel M. Castner

    2016-01-01

    Full Text Available Following exercise, heart rate decline is initially driven by parasympathetic reactivation and later by sympathetic withdrawal. Obesity delays endurance exercise heart rate recovery (HRR in both children and adults. Young people with Prader-Willi Syndrome (PWS, a congenital cause for obesity, have shown a slower 60-s endurance exercise HRR compared to lean and obese children, suggesting compromised regulation. This study further evaluated effects of obesity and PWS on resistance exercise HRR at 30 and 60 s in children. PWS (8–18 years and lean and obese controls (8–11 years completed a weighted step-up protocol (six sets x 10 reps per leg, separated by one-minute rest, standardized using participant stature and lean body mass. HRR was evaluated by calculated HRR value (HRRV = difference between HR at test termination and 30 (HRRV30 and 60 (HRRV60 s post-exercise. PWS and obese had a smaller HRRV30 than lean (p < 0.01 for both. Additionally, PWS had a smaller HRRV60 than lean and obese (p = 0.01 for both. Obesity appears to delay early parasympathetic reactivation, which occurs within 30 s following resistance exercise. However, the continued HRR delay at 60 s in PWS may be explained by either blunted parasympathetic nervous system reactivation, delayed sympathetic withdrawal and/or poor cardiovascular fitness.

  12. Síndrome de Prader-Labhart-Willi y apnea durante el sueño: A propósito de 3 pacientes Prader-Labhart-Willi syndrome and apnea during sleep: Apropos of 3 patients

    Directory of Open Access Journals (Sweden)

    Pedro González Fernández

    2004-08-01

    Full Text Available El síndrome de Prader-Labhart-Willi (SPW es una entidad que se asocia a trastornos respiratorios durante el sueño, lo que puede tener consecuencias fatales para la vida. Se presentan 3 pacientes con diagnóstico de SPW: 2 del sexo masculino y 1 del femenino. El diagnóstico en todos ellos fue confirmado después de los 2 años de edad. Los hallazgos clínicos más relevantes fueron: talla y peso corporal normal al nacimiento así como hipotonía muscular. En 2 pacientes la obesidad se inició después de los 2 años de edad y en el otro a los 18 meses de nacidos. La acromicria y retraso mental moderado estuvo presente en los 3 pacientes. Los resultados de los cariotipos por técnica de bandas fueron 46XY para los del sexo masculino y 46XX para la del femenino. Los 2 pacientes del sexo masculino presentaron episodios de apnea durante el sueño (Sleep Apnea Syndrome, lo que ocasionó el fallecimiento de ambos por paro respiratorio antes de los 12 años de edad. Se recomienda la vigilancia estrecha de estos pacientes, principalmente durante las infecciones respiratorias y las crisis de asma bronquial.Prader-Labhart-Willi syndrome (PWS is an entity associated with sleep disordered breathing, which may have fatal consequences for life. Three patients with diagnosis of PWS are presented: 2 males and 1 female. The diagnosis in all of them was confirmed after 2 years of age. The most significant clinical findings were: normal height and body weight at birth and muscular hypotonia. In two patients, obesity began at 2 years of age, and in one at 18 months of age. Acromicria and moderate mental retardation were observed in the three patients. The results of the karyotypes by band technique were 46XY for males and 46XX for females. The two male patients had episodes of sleep apnea (Sleep Apnea Syndrome, which caused their death due to respiratory arrest before being 12 years old. It is recommended the close surveillance of these patients, mainly during

  13. Event timing in high purity germanium coaxial detectors

    International Nuclear Information System (INIS)

    El-Ibiary, M.Y.

    1979-08-01

    The timing of gamma ray radiation in systems using high purity coaxial germanium detectors is analyzed and compared to that of systems using Ge(Li) detectors. The analysis takes into account the effect of the residual impurities on the electric field distribution, and hence on the rate of rise of the electrical pulses delivered to the timing module. Conditions under which the electric field distribution could lead to an improvement in timing performance, are identified. The results of the analysis confirm the experimental results published elsewhere and when compared with those for Ge(Li) detectors, which usually operate under conditions of charge carrier velocity saturation, confirm that high purity germanium detectors need not have inferior timing characteristics. A chart is given to provide a quantitative basis on which the trade off between the radius of the detector and its time resolution may be made

  14. Study of detectors in beta radiation fields

    International Nuclear Information System (INIS)

    Albuquerque, M. da P.P.; Xavier, M.; Caldas, L.V.E.

    1987-01-01

    Several commercial detectors used with gamma or X radiation are studied. Their sensibility and energetic dependence are analysed in exposures of beta radiation fields. A comparative evaluation with the reference detector (the extrapolation chamber) is presented. (M.A.C.) [pt

  15. Assessment of new small-field detectors against standard-field detectors for practical stereotactic beam data acquisition

    International Nuclear Information System (INIS)

    McKerracher, C.; Thwaites, D.I.

    1999-01-01

    Two new detectors (0.015 cm 3 ion chamber from PTW, 0.6 mm diameter diode from Scanditronix AB) designed specifically for use in small stereotactic fields were compared against similar, more routine, detectors (0.125 cm 3 ion chamber, parallel plate chamber, shielded and unshielded diodes and film). Percentage depth doses, tissue maximum ratios, off-axis ratios and relative output factors were compared for circular fields in the 40-12.5 mm diameter range, with a view to identifying the optimum detector for stereotactic beam data acquisition. Practical suggestions for beam data collection and analysis are made, with an emphasis on what is achievable practically in radiotherapy departments where the primary demand is to provide a routine service. No single detector was found to be ideal, and neither of the two new measurement devices had any significant advantages over more routine devices, in the situations measured. Although the new 0.015 cm 3 ion chamber was an improvement on a 0.125 cm 3 ion chamber in the measurement of profiles, it was still too large when compared with a diode. The new small diode had a low signal to noise ratio which made reliable data difficult to extract and its only advantage is possibly improved resolution in fields smaller than the range tested. The use of a larger unshielded diode is recommended for all measurements, with the additional cross-checking of data against at least one small ion chamber and film. A simple method of obtaining reliable output data from the detectors used is explained. (author)

  16. Measurements on a prototype segmented Clover detector

    CERN Document Server

    Shepherd, S L; Cullen, D M; Appelbe, D E; Simpson, J; Gerl, J; Kaspar, M; Kleinböhl, A; Peter, I; Rejmund, M; Schaffner, H; Schlegel, C; France, G D

    1999-01-01

    The performance of a segmented Clover germanium detector has been measured. The segmented Clover detector is a composite germanium detector, consisting of four individual germanium crystals in the configuration of a four-leaf Clover, housed in a single cryostat. Each crystal is electrically segmented on its outer surface into four quadrants, with separate energy read-outs from nine crystal zones. Signals are also taken from the inner contact of each crystal. This effectively produces a detector with 16 active elements. One of the purposes of this segmentation is to improve the overall spectral resolution when detecting gamma radiation emitted following a nuclear reaction, by minimising Doppler broadening caused by the opening angle subtended by each detector element. Results of the tests with sources and in beam will be presented. The improved granularity of the detector also leads to an improved isolated hit probability compared with an unsegmented Clover detector. (author)

  17. Disorders of Sleep and Ventilatory Control in Prader-Willi Syndrome

    Directory of Open Access Journals (Sweden)

    Emily S. Gillett

    2016-07-01

    Full Text Available Prader-Willi syndrome (PWS is an imprinted genetic disorder conferred by loss of paternal gene expression from chromosome 15q11.2-q13. Individuals with PWS have impairments in ventilatory control and are predisposed toward sleep disordered breathing due to a combination of characteristic craniofacial features, obesity, hypotonia, and hypothalamic dysfunction. Children with PWS progress from failure to thrive during infancy to hyperphagia and morbid obesity during later childhood and onward. Similarly, the phenotype of sleep disordered breathing in PWS patients also evolves over time from predominantly central sleep apnea in infants to obstructive sleep apnea (OSA in older children. Behavioral difficulties are common and may make establishing effective therapy with continuous positive airway pressure (CPAP more challenging when OSA persists after adenotonsillectomy. Excessive daytime sleepiness (EDS is also common in patients with PWS and may continue after OSA is effectively treated. We describe here the characteristic ventilatory control deficits, sleep disordered breathing, and excessive daytime sleepiness seen in individuals with PWS. We review respiratory issues that may contribute to sudden death events in PWS patients during sleep and wakefulness. We also discuss therapeutic options for treating sleep disordered breathing including adenotonsillectomy, weight loss, and CPAP. Lastly, we discuss the benefits and safety considerations related to growth hormone therapy.

  18. Zebrafish Models of Prader-Willi Syndrome: Fast Track to Pharmacotherapeutics

    Directory of Open Access Journals (Sweden)

    Emma D. Spikol

    2016-03-01

    Full Text Available Prader-Willi syndrome (PWS is a rare genetic neurodevelopmental disorder characterized by an insatiable appetite, leading to chronic overeating and obesity. Additional features include short stature, intellectual disability, behavioral problems and incomplete sexual development. Although significant progress has been made in understanding the genetic basis of PWS, the mechanisms underlying the pathogenesis of the disorder remain poorly understood. Treatment for PWS consists mainly of palliative therapies; curative therapies are sorely needed. Zebrafish, Danio rerio, represent a promising way forward for elucidating physiological problems such as obesity and identifying new pharmacotherapeutic options for PWS. Over the last decade, an increased appreciation for the highly conserved biology among vertebrates and the ability to perform high-throughput drug screening has seen an explosion in the use of zebrafish for disease modeling and drug discovery. Here, we review recent advances in developing zebrafish models of human disease. Aspects of zebrafish genetics and physiology that are relevant to PWS will be discussed, and the advantages and disadvantages of zebrafish models will be contrasted with current animal models for this syndrome. Finally, we will present a paradigm for drug screening in zebrafish that is potentially the fastest route for identifying and delivering curative pharmacotherapies to PWS patients.

  19. Good cognitive performances in a child with Prader-Willi syndrome.

    Science.gov (United States)

    Nugnes, Rosa; Zito, Eugenio; Mozzillo, Enza; Camarca, Maria Erminia; Riccio, Maria Pia; Terrone, Gaetano; Melis, Daniela; Bravaccio, Carmela; Franzese, Adriana

    2013-11-15

    We report the case of a child affected by Prader-Willi syndrome (PWS) with good cognitive performances and without relevant behavioral abnormalities.The diagnosis of PWS, suspected on the basis of clinical features and past history, was confirmed by DNA methylation analysis. Additional genetic testing revealed a maternal uniparental disomy. Intellectual profile was analyzed by WISC-III and Raven's Progressive Matrices CPM, while the behavior was evaluated by K-SADS-PL and Child Behavior Checklist/4-18 to the parents.WISC-III test showed a Total Intelligence Quotient (T-IQ = 79) at the border level for age. The Verbal Intelligence Quotient (V-IQ) showed a lower score than the Performance Intelligence Quotient (P-IQ) (78 and 85, respectively). Raven's Matrices CPM showed an intelligence level at 75-90° percentile for age. Concerning behavioral evaluation, a difficulty in impulse control was observed, with persistent but controllable search for food, without a clear psychopathological meaning. Also according to K-SADS-PL no areas of psychopathological dimensions were detected. In conclusion, in presence of consisting clinical features of PWS and high diagnostic suspicion, the diagnosis of PWS should be considered even in presence of a borderline IQ and in absence of psychopathological abnormalities.

  20. Venovenous Extracorporeal Membrane Oxygenation in an Adult Patient With Prader-Willi Syndrome: A Nutrition Case Report.

    Science.gov (United States)

    Pelekhaty, Stacy; Menaker, Jay

    2018-03-12

    Prader-Willi Syndrome (PWS) is a genetic condition that results in a constellation of symptoms and typically results in hyperphagia and obesity in adulthood. Critically ill adults with PWS present a unique challenge to the nutrition professional, particularly when they require support modalities such as extracorporeal membrane oxygenation (ECMO). The purpose of this case study is to review the nutrition care of a critically ill adult patient with PWS who required venovenous ECMO. The patient was successfully managed with a hypocaloric, high-protein approach, which did not result in the diagnosis of malnutrition during his hospitalization. The patient was ultimately transitioned off extracorporeal life support and discharged to a rehabilitation facility. © 2018 American Society for Parenteral and Enteral Nutrition.

  1. Subclinical dysphagia in persons with Prader-Willi syndrome.

    Science.gov (United States)

    Gross, Roxann Diez; Gisser, Ronit; Cherpes, Gregory; Hartman, Katie; Maheshwary, Rishi

    2017-02-01

    Prader-Willi Syndrome (PWS) is caused by a genetic imprinting abnormality resulting from the lack of expression of the paternal genes at 15q11-q13. Intellectual disability, low muscle tone, and life-threatening hyperphagia are hallmarks of the phenotype. The need for the Heimlich maneuver, death from choking, and pulmonary infection occur in a disproportionally high number of persons with PWS. The widely held belief is that eating behaviors are responsible for choking and aspiration; yet, no investigation had sought to determine if swallowing impairments were present in persons with PWS. To address this research and clinical gap, simultaneous videofluoroscopy and nasal respiratory signals were used to record swallowing function and breathing/swallowing coordination in 30 participants with PWS. Subjects consumed thin liquid and barium cookies under two randomized conditions as follows: (i) controlled (cues to swallow and standardized bolus sizes); (ii) spontaneous (no cues or bolus size control). Under videofluoroscopy, the cohort showed disordered pharyngeal and esophageal swallowing in both conditions with disturbances in timing, clearance, and coordination of swallowing with the respiratory cycle. No participant showed a sensory response such as attempting to clear residue or coughing; thereby supporting the lack of overt symptoms. We conclude that the high death rate from choking and pulmonary infection in children and adults with PWS may be related, in part, to underlying, asymptomatic dysphagia. The combination of rapid eating and dysphagia would increase the risk of aspiration-related morbidity and mortality. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  2. Effects of Adiposity and Prader-Willi Syndrome on Postexercise Heart Rate Recovery

    Directory of Open Access Journals (Sweden)

    Diobel M. Castner

    2013-01-01

    Full Text Available Heart rate recovery (HRR is an indicator of all-cause mortality in children and adults. We aimed to determine the effect of adiposity and Prader-Willi Syndrome (PWS, a congenital form of obesity, on HRR. Sixteen children of normal weight (NW = body fat % ≤85th percentile, 9.4 ± 1.1 y, 18 children with obesity (OB = body fat % >95th percentile, 9.3 ± 1.1 y, and 11 PWS youth (regardless of body fat %; 11.4 ± 2.5 y completed peak and submaximal bike tests on separate visits. HRR was recorded one minute following peak and submaximal exercises. All groups displayed similar HRR from peak exercise, while NW (54 ± 16 beats and OB (50 ± 12 beats exhibited a significantly faster HRR from submaximal exercise than PWS (37 ± 14 beats. These data suggest that excess adiposity does not influence HRR in children, but other factors such as low cardiovascular fitness and/or autonomic dysfunction might be more influential.

  3. Prader-Willi Syndrome: The Disease that Opened up Epigenomic-Based Preemptive Medicine

    Directory of Open Access Journals (Sweden)

    Takeo Kubota

    2016-03-01

    Full Text Available Prader-Willi syndrome (PWS is a congenital neurodevelopmental disorder caused by loss of function of paternally expressed genes on chromosome 15 due to paternal deletion of 15q11–q13, maternal uniparental disomy for chromosome 15, or an imprinting mutation. We previously developed a DNA methylation-based PCR assay to identify each of these three genetic causes of PWS. The assay enables straightforward and rapid diagnosis during infancy and therefore allows early intervention such as nutritional management, physical therapy, or growth hormone treatment to prevent PWS patients from complications such as obesity and type 2 diabetes. It is known that various environmental factors induce epigenomic changes during the perinatal period, which increase the risk of adult diseases such as type 2 diabetes and intellectual disabilities. Therefore, a similar preemptive approach as used in PWS would also be applicable to acquired disorders and would make use of environmentally-introduced “epigenomic signatures” to aid development of early intervention strategies that take advantage of “epigenomic reversibility”.

  4. Gender Differences in the Behavioral Symptom Severity of Prader-Willi Syndrome

    Directory of Open Access Journals (Sweden)

    Masao Gito

    2015-01-01

    Full Text Available Objectives. This study measured gender differences in Prader-Willi syndrome (PWS in regard to the severity of behavioral symptoms. Methods. The Food Related Problem Questionnaire (FRPQ, the Aberrant Behavior Checklist Japanese Version, the Childhood Routines Inventory, the Pervasive Developmental Disorders Autism Society Japan Rating Scale, and Japanese ADHD-RS were administered to PWS patients (45 males aged 6 to 58 and 37 females aged 6 to 45. To examine the effects that gender and genotype have on the severity of each symptom, two-way ANOVAs were conducted. Results. Significant interactions were found only in regard to FRPQ scores, such as FRPQ total score (F(1, 78 = 8.43, p<0.01. The FRPQ of male deletion (DEL individuals was higher than that of female DEL and male mUPD. The FRPQ of male maternal uniparental disomy (mUPD was lower than that of female mUPD. Conclusions. In terms of problem behaviors, routines, autistic behaviors, and hyperactivity, no significant differences were found. Food-related behaviors in DEL were more severe in males, although those in mUPD were less severe in males.

  5. Optimal linear detectors for nonorthogonal amplify-and-forward protocol

    KAUST Repository

    Ahmed, Qasim Zeeshan; Park, Kihong; Alouini, Mohamed-Slim; Aissa, Sonia

    2013-01-01

    In this paper, we propose optimal linear detectors for non-orthogonal amplify-and-forward cooperative protocol when considering a single-relay scenario. Two types of detectors are proposed based on the principles of minimum mean square error (MMSE) and minimum bit error rate (MBER). The MMSE detector minimizes the mean square error, while the MBER minimizes the system bit error rate (BER). Both detectors exhibit excellent BER performance with relatively low complexity as compared to the maximal likelihood (ML) detector. The BER performance of both detectors is superior to the channel inversion, the maximal ratio combining, and the biased ML detectors. © 2013 IEEE.

  6. Optimal linear detectors for nonorthogonal amplify-and-forward protocol

    KAUST Repository

    Ahmed, Qasim Zeeshan

    2013-06-01

    In this paper, we propose optimal linear detectors for non-orthogonal amplify-and-forward cooperative protocol when considering a single-relay scenario. Two types of detectors are proposed based on the principles of minimum mean square error (MMSE) and minimum bit error rate (MBER). The MMSE detector minimizes the mean square error, while the MBER minimizes the system bit error rate (BER). Both detectors exhibit excellent BER performance with relatively low complexity as compared to the maximal likelihood (ML) detector. The BER performance of both detectors is superior to the channel inversion, the maximal ratio combining, and the biased ML detectors. © 2013 IEEE.

  7. A further case of a Prader-Willi syndrome phenotype in a patient with Angelman syndrome molecular defect

    Directory of Open Access Journals (Sweden)

    De Molfetta Greice Andreotti

    2002-01-01

    Full Text Available Angelman syndrome (AS and Prader-Willi syndrome (PWS are distinct human neurogenetic disorders; however, a clinical overlap between AS and PWS has been identified. We report on a further case of a patient showing the PWS phenotype with the AS molecular defect. Despite the PWS phenotype, the DNA methylation analysis of SNRPN revealed an AS pattern. Cytogenetic and FISH analysis showed normal chromosomes 15 and microsatellite analysis showed heterozygous loci inside and outside the 15q11-13 region. The presence of these atypical cases could be more frequent than previously expected and we reinforce that the DNA methylation analysis is important for the correct diagnosis of severe mental deficiency, congenital hypotonia and obesity.

  8. Detectors for proton counting. Si-APD and scintillation detectors

    International Nuclear Information System (INIS)

    Kishimoto, Shunji

    2008-01-01

    Increased intensity of synchrotron radiation requests users to prepare photon pulse detectors having higher counting rates. As detectors for photon counting, silicon-avalanche photodiode (Si-APD) and scintillation detectors were chosen for the fifth series of detectors. Principle of photon detection by pulse and need of amplification function of the detector were described. Structure and working principle, high counting rate measurement system, bunch of electrons vs. counting rate, application example of NMR time spectroscopy measurement and comments for users were described for the Si-APD detector. Structure of scintillator and photomultiplier tube, characteristics of scintillator and performance of detector were shown for the NaI detector. Future development of photon pulse detectors was discussed. (T. Tanaka)

  9. Position sensitive detector for X-ray photons

    International Nuclear Information System (INIS)

    Barbosa, A.F.

    1988-01-01

    This work reports the theoretical basis and the details of the construction process, characterization and application of gas X-ray position sensitive detectors. The unidimensional detector consists of a gas camera (argon and CH 4 ), a metallic anode, a cathode and a delay line. Details of the construction process are given in order to allow the reproduction of the detector. It has been characterized by measuring its spatial resolution, homogeneity and linerity. The built linear detector has been used to obtain diffraction diagrams from polycrystalline silicon, C 23 H 48 paraffin and glassy carbon. These diagrams have been compared with those obtained under equivalent conditions with a conventional proportional detector by the step scanning method. It has been shown that the detector provides diffraction diagrams of equivalent quality to those obtained by the step scanning method, in appreciably lower time intervals. (author) [pt

  10. Comparative measurements of soil gas radon concentration using thermoluminescent and track detectors

    Czech Academy of Sciences Publication Activity Database

    Turek, Karel; Gelev, M.; Dimov, I.

    2004-01-01

    Roč. 38, spec. iss. (2004), s. 843-846 ISSN 1350-4487 Institutional research plan: CEZ:AV0Z1048901 Keywords : soil gas * radon concentration * thermoluminescent detectors Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 0.664, year: 2004

  11. A New Virtual Point Detector Concept for a HPGe detector

    International Nuclear Information System (INIS)

    Byun, Jong In; Yun, Ju Yong

    2009-01-01

    For last several decades, the radiation measurement and radioactivity analysis techniques using gamma detectors have been well established. Especially , the study about the detection efficiency has been done as an important part of gamma spectrometry. The detection efficiency depends strongly on source-to-detector distance. The detection efficiency with source-to-detector distance can be expressed by a complex function of geometry and physical characteristics of gamma detectors. In order to simplify the relation, a virtual point detector concept was introduced by Notea. Recently, further studies concerning the virtual point detector have been performed. In previous other works the virtual point detector has been considered as a fictitious point existing behind the detector end cap. However the virtual point detector position for the front and side of voluminous detectors might be different due to different effective central axis of them. In order to more accurately define the relation, therefore, we should consider the virtual point detector for the front as well as side and off-center of the detector. The aim of this study is to accurately define the relation between the detection efficiency and source-to-detector distance with the virtual point detector. This paper demonstrates the method to situate the virtual point detectors for a HPGe detector. The new virtual point detector concept was introduced for three area of the detector and its characteristics also were demonstrated by using Monte Carlo Simulation method. We found that the detector has three virtual point detectors except for its rear area. This shows that we should consider the virtual point detectors for each area when applying the concept to radiation measurement. This concept can be applied to the accurate geometric simplification for the detector and radioactive sources.

  12. Transmutation detectors

    Energy Technology Data Exchange (ETDEWEB)

    Viererbl, L., E-mail: vie@ujv.c [Research Centre Rez Ltd. (Czech Republic); Nuclear Research Institute Rez plc (Czech Republic); Lahodova, Z. [Research Centre Rez Ltd. (Czech Republic); Nuclear Research Institute Rez plc (Czech Republic); Klupak, V. [Nuclear Research Institute Rez plc (Czech Republic); Sus, F. [Research Centre Rez Ltd. (Czech Republic); Nuclear Research Institute Rez plc (Czech Republic); Kucera, J. [Research Centre Rez Ltd. (Czech Republic); Nuclear Physics Institute, Academy of Sciences of the Czech Republic (Czech Republic); Kus, P.; Marek, M. [Research Centre Rez Ltd. (Czech Republic); Nuclear Research Institute Rez plc (Czech Republic)

    2011-03-11

    We have designed a new type of detectors, called transmutation detectors, which can be used primarily for neutron fluence measurement. The transmutation detector method differs from the commonly used activation detector method in evaluation of detector response after irradiation. Instead of radionuclide activity measurement using radiometric methods, the concentration of stable non-gaseous nuclides generated by transmutation in the detector is measured using analytical methods like mass spectrometry. Prospective elements and nuclear reactions for transmutation detectors are listed and initial experimental results are given. The transmutation detector method could be used primarily for long-term measurement of neutron fluence in fission nuclear reactors, but in principle it could be used for any type of radiation that can cause transmutation of nuclides in detectors. This method could also be used for measurement in accelerators or fusion reactors.

  13. Transmutation detectors

    International Nuclear Information System (INIS)

    Viererbl, L.; Lahodova, Z.; Klupak, V.; Sus, F.; Kucera, J.; Kus, P.; Marek, M.

    2011-01-01

    We have designed a new type of detectors, called transmutation detectors, which can be used primarily for neutron fluence measurement. The transmutation detector method differs from the commonly used activation detector method in evaluation of detector response after irradiation. Instead of radionuclide activity measurement using radiometric methods, the concentration of stable non-gaseous nuclides generated by transmutation in the detector is measured using analytical methods like mass spectrometry. Prospective elements and nuclear reactions for transmutation detectors are listed and initial experimental results are given. The transmutation detector method could be used primarily for long-term measurement of neutron fluence in fission nuclear reactors, but in principle it could be used for any type of radiation that can cause transmutation of nuclides in detectors. This method could also be used for measurement in accelerators or fusion reactors.

  14. Depth sensitivity of Lexan polycarbonate detector

    CERN Document Server

    Awad, E M

    1999-01-01

    The dependence of the registration sensitivity of Lexan polycarbonate with depth inside the detector was studied. Samples of Lexan from General Electric were irradiated to two long range ions. These were Ni and Au ions with a projectile energy of 0.3 and 1 GeV/n. Two independent techniques, the track-diameter technique (TDT) and the track profile technique (TPT), were used. The registration sensitivity was measured at depths of 7, 10, 15, 18, 20, 28, 35 and 40 mu m inside the detector. The results of the two techniques show that the detector sensitivity decreases gradually with the depth inside the detector. It reaches 20 % less compared to sensitivity at the surface after 40 mu m have been removed.

  15. Characterizing X-ray detectors for prototype digital breast tomosynthesis systems

    International Nuclear Information System (INIS)

    Kim, Y.-S.; Park, H.-S.; Park, S.-J.; Choi, S.; Lee, H.; Kim, H.-J.; Lee, D.; Choi, Y.-W.

    2016-01-01

    The digital breast tomosynthesis (DBT) system is a newly developed 3-D imaging technique that overcomes the tissue superposition problems of conventional mammography. Therefore, it produces fewer false positives. In DBT system, several parameters are involved in image acquisition, including geometric components. A series of projections should be acquired at low exposure. This makes the system strongly dependent on the detector's characteristic performance. This study compares two types of x-ray detectors developed by the Korea Electrotechnology Research Institute (KERI). The first prototype DBT system has a CsI (Tl) scintillator/CMOS based flat panel digital detector (2923 MAM, Dexela Ltd.), with a pixel size of 0.0748 mm. The second uses a-Se based direct conversion full field detector (AXS 2430, analogic) with a pixel size of 0.085 mm. The geometry of both systems is same, with a focal spot 665.8 mm from the detector, and a center of rotation 33 mm above the detector surface. The systems were compared with regard to modulation transfer function (MTF), normalized noise power spectrum (NNPS), detective quantum efficiency (DQE) and a new metric, the relative object detectability (ROD). The ROD quantifies the relative performance of each detector at detecting specified objects. The system response function demonstrated excellent linearity (R 2 >0.99). The CMOS-based detector had a high sensitivity, while the Anrad detector had a large dynamic range. The higher MTF and noise power spectrum (NPS) values were measured using an Anrad detector. The maximum DQE value of the Dexela detector was higher than that of the Anrad detector with a low exposure level, considering one projection exposure for tomosynthesis. Overall, the Dexela detector performed better than did the Anrad detector with regard to the simulated Al wires, spheres, test objects of ROD with low exposure level. In this study, we compared the newly developed prototype DBT system with two different types

  16. Detector Control System for the ATLAS Forward Proton detector

    CERN Document Server

    Czekierda, Sabina; The ATLAS collaboration

    2017-01-01

    The ATLAS Forward Proton (AFP) is a forward detector using a Roman Pot technique, recently installed in the LHC tunnel. It is aiming at registering protons that were diffractively or electromagnetically scattered in soft and hard processes. Infrastructure of the detector consists of hardware placed both in the tunnel and in the control room USA15 (about 330 meters from the Roman Pots). AFP detector, like the other detectors of the ATLAS experiment, uses the Detector Control System (DCS) to supervise the detector and to ensure its safe and coherent operation, since the incorrect detector performance may influence the physics results. The DCS continuously monitors the detector parameters, subset of which is stored in data bases. Crucial parameters are guarded by alarm system. A detector representation as a hierarchical tree-like structure of well-defined subsystems built with the use of the Finite State Machine (FSM) toolkit allows for overall detector operation and visualization. Every node in the hierarchy is...

  17. Neutrino induced events in the MINOS detectors

    International Nuclear Information System (INIS)

    Litchfield, Reuben Phillip

    2008-01-01

    The MINOS experiment is designed to study neutrino oscillations. It uses an accelerator generated beam of neutrinos and two detectors, the smaller at a distance of 1km and the larger at 735 km. By comparing the spectrum and flavour composition of the beam at the two detectors precise determinations of the oscillation parameters are possible. This thesis concentrates on the analysis of data from the larger Far Detector. By studying the spectrum of neutral current events it is possible to look for evidence of non-interacting 'sterile' neutrinos. The thesis describes how events are selected for this analysis, and a method for discriminating between charged current and neutral current events. The systematic uncertainties resulting from these cuts are evaluated. Several techniques for using Near Detector data to eliminate systematic uncertainties in the predicted Far Detector spectrum are compared. An oscillation analysis, based on the first year of MINOS data, uses the selected events to make a measurement of f s , the fraction of unseen neutrinos that are sterile. The measured value is f s = 0.07 +0.32 at 68%C.L., and is consistent with the standard three-neutrino picture, which has no sterile neutrino

  18. Spectral correction algorithm for multispectral CdTe x-ray detectors

    DEFF Research Database (Denmark)

    Christensen, Erik D.; Kehres, Jan; Gu, Yun

    2017-01-01

    Compared to the dual energy scintillator detectors widely used today, pixelated multispectral X-ray detectors show the potential to improve material identification in various radiography and tomography applications used for industrial and security purposes. However, detector effects, such as charge...

  19. Digital radiography with large-area flat-panel detectors

    International Nuclear Information System (INIS)

    Kotter, E.; Langer, M.

    2002-01-01

    Large-area flat-panel detectors with active readout mechanisms have been on the market for the past 2 years. This article describes different detector technologies. An important distinction is made between detectors with direct and those with indirect conversion of X-rays into electrical charges. Detectors with indirect conversion are built with unstructured or structured scintillators, the latter resulting in less lateral diffusion of emitted light. Some important qualities of flat-panel detectors are discussed. The first phantom and clinical studies published report an image quality at least comparable to that of screen-film systems and a potential for dose reduction. The available studies are summarised in this article. (orig.)

  20. Calibration of Nuclear Track Detectors

    International Nuclear Information System (INIS)

    Vukovic, J.B; Antanasijevic, R.; Novakovic, V.; Tasic, M.

    1998-01-01

    In this work we compare some of our preliminary results relating to the calibration Nuclear Track Detectors (NTD) with corresponding results obtained from other participants at the First International Intercomparison of Image Analyzers (III 97/98). Thirteen laboratories from Algeria, China, Czech Rep., France. Germany, Greece, Hungary, India, Italy, Mexico, Saudi Arabia, Slovenia and Yugoslavia participated in the III A 97/98. The NTD was 'Tustrack', Bristol. This type of CR-39 detector was etched by the organizer (J.Paltarey of al, Atomic Energy Research Institute, HPD, Budapest, Hungary). Etching condition was: 6N NaOH, 70 0C . Seven series detectors were exposed with the sources: B(n,a)Li, Am-241, Pu-Be(n,p), Radon and Am-Cm-Pu. Following parameters of exposed detectors were measured: track density of different sorts of tracks (circular, elliptical, track overlapping, their diameters, major and minor axis and other). (authors)

  1. The LDC detector concept

    Indian Academy of Sciences (India)

    foresees a TPC with around 200 points measured along a track, and read out by a system of micro-pattern gas detectors. These novel gas amplification devices promise to provide a stable, reliable readout system, which can be realized with comparatively little material in the endplate compared to a traditional wire readout.

  2. Detector for flow abnormalities in gaseous diffusion plant compressors

    Science.gov (United States)

    Smith, S.F.; Castleberry, K.N.

    1998-06-16

    A detector detects a flow abnormality in a plant compressor which outputs a motor current signal. The detector includes a demodulator/lowpass filter demodulating and filtering the motor current signal producing a demodulated signal, and first, second, third and fourth bandpass filters connected to the demodulator/lowpass filter, and filtering the demodulated signal in accordance with first, second, third and fourth bandpass frequencies generating first, second, third and fourth filtered signals having first, second, third and fourth amplitudes. The detector also includes first, second, third and fourth amplitude detectors connected to the first, second, third and fourth bandpass filters respectively, and detecting the first, second, third and fourth amplitudes, and first and second adders connected to the first and fourth amplitude detectors and the second and third amplitude detectors respectively, and adding the first and fourth amplitudes and the second and third amplitudes respectively generating first and second added signals. Finally, the detector includes a comparator, connected to the first and second adders, and comparing the first and second added signals and detecting the abnormal condition in the plant compressor when the second added signal exceeds the first added signal by a predetermined value. 6 figs.

  3. The pin detector - a simple, robust, cheap and effective nuclear radiation detector

    International Nuclear Information System (INIS)

    Bateman, J.E.

    1984-01-01

    The development of a series of radiation detectors bases on the point anode is reported. Using readily available preformed pins from a variety of electrical connectors as the anodes, a family of devices has been created with useful properties as X-ray detectors, radiation monitors and internal beta counters. A wide variety of gas fillings can be used, argon/CH 4 premix being the most convenient. The structures are robust and call for no precision alignments so keeping costs down. Performance of the devices in respect of sensitivity and pulse height resolution is comparable to that of conventional wire counters. (author)

  4. Generalized mean detector for collaborative spectrum sensing

    KAUST Repository

    Shakir, Muhammad Zeeshan

    2013-04-01

    In this paper, a unified generalized eigenvalue based spectrum sensing framework referred to as Generalized mean detector (GMD) has been introduced. The generalization of the detectors namely (i) the eigenvalue ratio detector (ERD) involving the ratio of the largest and the smallest eigenvalues; (ii) the Geometric mean detector (GEMD) involving the ratio of the largest eigenvalue and the geometric mean of the eigenvalues and (iii) the Arithmetic mean detector (ARMD) involving the ratio of the largest and the arithmetic mean of the eigenvalues is explored. The foundation of the proposed unified framework is based on the calculation of exact analytical moments of the random variables of test statistics of the respective detectors. In this context, we approximate the probability density function (PDF) of the test statistics of the respective detectors by Gaussian/Gamma PDF using the moment matching method. Finally, we derive closed-form expressions to calculate the decision threshold of the eigenvalue based detectors by exchanging the derived exact moments of the random variables of test statistics with the moments of the Gaussian/Gamma distribution function. The performance of the eigenvalue based detectors is compared with the traditional detectors such as energy detector (ED) and cyclostationary detector (CSD) and validate the importance of the eigenvalue based detectors particularly over realistic wireless cognitive environments. Analytical and simulation results show that the GEMD and the ARMD yields considerable performance advantage in realistic spectrum sensing scenarios. Moreover, our results based on proposed simple and tractable approximation approaches are in perfect agreement with the empirical results. © 1972-2012 IEEE.

  5. Respiratory Failure due to Severe Obesity and Kyphoscoliosis in a 24-Year-Old Male with Molecularly Confirmed Prader-Willi Syndrome in Tertiary Hospital in Northern Tanzania

    Directory of Open Access Journals (Sweden)

    Elichilia R. Shao

    2017-01-01

    Full Text Available Obesity, mild intellectual disability, hypotonia, poor sucking, cryptorchidism in males, hypogonadism, and kyphoscoliosis are common features of Prader-Willi syndrome (PWS. We report a case who had severe respiratory complications due to extreme obesity and kyphoscoliosis, which are important causes of morbidity and mortality, and discuss management. Furthermore, this is the first molecularly confirmed PWS case in Sub-Saharan Africa outside South Africa.

  6. Calibration of detector efficiency of neutron detector

    International Nuclear Information System (INIS)

    Guo Hongsheng; He Xijun; Xu Rongkun; Peng Taiping

    2001-01-01

    BF 3 neutron detector has been set up. Detector efficiency is calibrated by associated particle technique. It is about 3.17 x 10 -4 (1 +- 18%). Neutron yield of neutron generator per pulse (10 7 /pulse) is measured by using the detector

  7. Nutritional intervention with hypocaloric diet for weight control in children and adolescents with Prader-Willi Syndrome.

    Science.gov (United States)

    Lima, Vivian Penner de; Emerich, Deisy Ribas; Mesquita, Maria Luiza Guedes de; Paternez, Ana Carolina Almada Colucci; Carreiro, Luiz Renato Rodrigues; Pina Neto, João Monteiro de; Teixeira, Maria Cristina Triguero Veloz

    2016-04-01

    Prader-Willi Syndrome (PWS) is a genetic disorder caused by the lack of expression of paternal alleles in the proximal region of the long arm of chromosome 15. Low inhibitory control and hyperphagia are two of the most severe neurobehavioral symptoms of the syndrome. The aim of the present study was to assess the efficiency of nutritional training program with the use hypocaloric diet for weight control in a group of five children and adolescents with PWS. The intervention program consisted of 10 sessions for parents' orientation during 8months. Patients had their anthropometric measures assessed (weight, height and body mass index - BMI). The main results indicate weight maintenance, height increase, and BMI decrease after intervention. These results were considered indicators of the program's efficiency. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. An 18-year-old patient with Prader-Willi syndrome: a case report on dental management under sedation and general anesthesia.

    Science.gov (United States)

    Song, Ki Un; Nam, Ok Hyung; Kim, Mi Sun; Choi, Sung Chul; Lee, Hyo-Seol

    2015-12-01

    Prader-Willi syndrome (PWS) is a rare genetic disorder reported rarely in dentistry. Dental practitioners should know the features of PWS because affected patients have a variety of dental symptoms. The current report describes a case of PWS. An 18-year-old male patient presented with traumatic injuries. Initial emergency treatments were performed under sedation, and further treatments were conducted under general anesthesia. After adequate healing, periodic follow-up and dietary management according to the patient's age and nutritional phase were recommended. Dental management of PWS patients consists of active preventive measures in addition to dietary consultation according to age and nutritional phase.

  9. Scintillation neutron detector with dynamic threshold

    International Nuclear Information System (INIS)

    Kornilov, N.; Massey, T.; Grimes, S.

    2014-01-01

    Scintillation neutron detectors with hydrogen are a common tool for neutron spectroscopy. They provide good time resolution, neutron-gamma discrimination and high efficiency of neutron counting. The real open problems connected with application of these detectors are in the energy range >10 MeV. There are no standard neutron spectra known with high accuracy for this energy range. Therefore, traditional methods for experimental investigation of the efficiency function fail for these neutrons. The Monte Carlo simulation cannot provide reasonable accuracy due to unknown characteristics of the reactions for charged particle production (p, α and so on, light output, reaction cross-sections). The application of fission chamber with fissile material as a neutron detector did not help to solve the problem. We may avoid many problems if we use the traditional neutron detector with non-traditional data analysis. In this report we give main relations, and demonstrate the method for Cf-source. Experimental detector efficiency is compared with MC simulation. (authors)

  10. Initial results from 3D-DDTC detectors on p-type substrates

    Energy Technology Data Exchange (ETDEWEB)

    Zoboli, A., E-mail: zoboli@disi.unitn.i [Dipartimento di Ingegneria e Scienza dell' Informazione, Universita di Trento, and INFN, Sezione di Padova (Gruppo Collegato di Trento), Via Sommarive, 14, I-38100 Povo di Trento (Italy); Boscardin, M. [Fondazione Bruno Kessler, Centro per i Materiali e i Microsistemi, Via Sommarive, 18, I-38100 Povo di Trento (Italy); Bosisio, L. [Dipartimento di Fisica, Universita di Trieste, and INFN, Sezione di Trieste, Via A. Valerio, 2, I-34127 Trieste (Italy); Dalla Betta, G.-F. [Dipartimento di Ingegneria e Scienza dell' Informazione, Universita di Trento, and INFN, Sezione di Padova (Gruppo Collegato di Trento), Via Sommarive, 14, I-38100 Povo di Trento (Italy); Piemonte, C.; Ronchin, S.; Zorzi, N. [Fondazione Bruno Kessler, Centro per i Materiali e i Microsistemi, Via Sommarive, 18, I-38100 Povo di Trento (Italy)

    2010-01-11

    Owing to their superior radiation hardness compared to planar detectors, 3D detectors are one of the most promising technologies for the LHC upgrade foreseen in 2017. Fondazione Bruno Kessler has developed 3D Double-side Double-Type Column (3D-DDTC) detectors providing a technological simplifications with respect to a standard 3D process while aiming at comparable detector performance. We present selected results from the electrical characterization of 3D-DDTC structures from the second batch made on p-type substrates, supported also by TCAD simulations.

  11. Modeling the Efficiency of a Germanium Detector

    Science.gov (United States)

    Hayton, Keith; Prewitt, Michelle; Quarles, C. A.

    2006-10-01

    We are using the Monte Carlo Program PENELOPE and the cylindrical geometry program PENCYL to develop a model of the detector efficiency of a planar Ge detector. The detector is used for x-ray measurements in an ongoing experiment to measure electron bremsstrahlung. While we are mainly interested in the efficiency up to 60 keV, the model ranges from 10.1 keV (below the Ge absorption edge at 11.1 keV) to 800 keV. Measurements of the detector efficiency have been made in a well-defined geometry with calibrated radioactive sources: Co-57, Se-75, Ba-133, Am-241 and Bi-207. The model is compared with the experimental measurements and is expected to provide a better interpolation formula for the detector efficiency than simply using x-ray absorption coefficients for the major constituents of the detector. Using PENELOPE, we will discuss several factors, such as Ge dead layer, surface ice layer and angular divergence of the source, that influence the efficiency of the detector.

  12. Extrinsic Fabry-Perot ultrasonic detector

    Science.gov (United States)

    Kidwell, J. J.; Berthold, John W., III

    1996-10-01

    We characterized the performance of a commercial fiber optic extrinsic Fabry-Perot interferometer for use as an ultrasonic sensor, and compared the performance with a standard lead zirconate titanate (PZT) detector. The interferometer was unstabilized. The results showed that the fiber sensor was about 12 times less sensitive than the PZT detector. Ultrasonic frequency response near 100 kHz was demonstrated. We describe the design of the fiber sensor, the details of the tests performed, and potential applications.

  13. Radiation response issues for infrared detectors

    Science.gov (United States)

    Kalma, Arne H.

    1990-01-01

    Researchers describe the most important radiation response issues for infrared detectors. In general, the two key degradation mechanisms in infrared detectors are the noise produced by exposure to a flux of ionizing particles (e.g.; trapped electronics and protons, debris gammas and electrons, radioactive decay of neutron-activated materials) and permanent damage produced by exposure to total dose. Total-dose-induced damage is most often the result of charge trapping in insulators or at interfaces. Exposure to short pulses of ionization (e.g.; prompt x rays or gammas, delayed gammas) will cause detector upset. However, this upset is not important to a sensor unless the recovery time is too long. A few detector technologies are vulnerable to neutron-induced displacement damage, but fortunately most are not. Researchers compare the responses of the new technologies with those of the mainstream technologies of PV HgCdTe and IBC Si:As. One important reason for this comparison is to note where some of the newer technologies have the potential to provide significantly improved radiation hardness compared with that of the mainstream technologies, and thus to provide greater motivation for the pursuit of these technologies.

  14. The arterial circle of Willis of the mouse helps to decipher secrets of cerebral vascular accidents in the human.

    Science.gov (United States)

    Okuyama, Shinichi; Okuyama, Jun; Okuyama, Junko; Tamatsu, Yuichi; Shimada, Kazuyuki; Hoshi, Hajime; Iwai, Junichi

    2004-01-01

    The human brain represents an elaborate product of hominizing evolution. Likewise, its supporting vasculature may also embody evolutionary consequences. Thus, it is conceivable that the human tendency to develop cerebral vascular accidents (CVAs) might represent a disease of hominization. In a search for hominizing changes on the arterial circle of Willis (hWAC), we attempted an anatomical comparison of the hWAC with that of the mouse (mWAC) by injecting aliquots of resin into the vasculature of the mouse and then creating vascular endocasts of the mWAC. The internal carotid artery of the mouse (mICA) unites with the mWAC midway between the middle cerebral artery (mMCA) and posterior cerebral artery (mPCA). The mWAC does not complete a circle: the mWAC nourishes the anterior portion of the circle which branches out to the olfactory artery (OlfA) and mPCA, along with the mMCA, and the basilar artery (mBA) does not connect to the mPCA. The OlfA is thicker than the mMCA. The relative brain weight of the mouse was 74 g on average for a 60 kg male and 86 g for a 60 kg female, respectively, as compared with 1424 g for a 60 kg man. These findings are consistent with the mouse being a nocturnal carnivore that lives on olfactory information in contrast to the human that lives diurnally and depends on visual and auditory information. In man, the human ICA (hICA) unites with the hWAC at a point where the human middle cerebral artery (hMCA) branches out, and thus, blood from the hICA does not flow through the hWAC but drains into the hMCA directly. The hMCA is thicker than the anterior cerebral artery. The hPCA receives blood from the hBA rather than from the hICA, and thus, the entire hWAC forms a closed circuit. Since the hICA drains directly into the hMCA without flowing a distance through the hWAC, the capacitor and equalizer functions of the WAC will be mitigated so much that the resultant hemodynamic changes would render the hMCA more likely to contribute to CVAs. Thus

  15. The role of contacts in semiconductor gamma radiation detectors

    International Nuclear Information System (INIS)

    Lachish, U.

    1998-01-01

    It is proposed that the operation of semiconductor gamma radiation detectors, equipped with ohmic contacts, which allow free electron flow between the contacts and bulk material, will not be sensitive to low hole mobility, hole collection efficiency, or hole trapping. Such fast-operating detectors may be readily integrated into monolithic arrays. The detection mechanism and various material aspects are discussed and compared to those of blocking contact detectors. Some suggestions for detector realization are presented. (orig.)

  16. Paradise and Politics in the Music of Blind Willie Johnson

    Directory of Open Access Journals (Sweden)

    Owen Coggins

    2012-05-01

    Full Text Available I investigate the politics of paradises in the 1920s African-American gospel blues of Blind Willie Johnson. His recordings are apocalyptic vignettes which juxtapose and conflate paradises, using many different voices. I describe the theological and political paradises in Johnson’s songs: the Old Testament journey to Canaan; the post-death heaven in the New Testament; Christ’s kingdom on earth in Revelation; freedom in Northern cities or Canada; and a utopian dream of political emancipation of African-Americans and transformation of society in the South. I outline the various voices present in Johnson’s recordings: vocal styles; accompanying singers; the guitar; grammatical, textual and lexical voices; and the silent voices of technology and time. I suggest traces of a subtle political activism in these voices and paradises, and explore uses of these voices in linking paradises, arguing that the complex transitions enhance the force of signification and frustrate attempts to finalise meanings. Many interpretations of Johnson’s recordings, however, seek to determine final meaning, and I discuss the limitations of such attempts, limitations which not only underestimate the richness of the recordings but deny Johnson any political awareness or agency. In cautioning against this kind of project, I call for a hearing open to plural interpretations, and suggest political potential not only in coded messages, but in radical indeterminacy itself.

  17. Radiation detectors laboratory; Laboratorio de detectores de radiacion

    Energy Technology Data Exchange (ETDEWEB)

    Ramirez J, F.J. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    1997-07-01

    The Radiation detectors laboratory was established with the assistance of the International Atomic Energy Agency which gave this the responsibility to provide its services at National and regional level for Latin America and it is located at the ININ. The more expensive and delicate radiation detectors are those made of semiconductor, so it has been put emphasis in the use and repairing of these detectors type. The supplied services by this laboratory are: selection consultant, detectors installation and handling and associated systems. Installation training, preventive and corrective maintenance of detectors and detection systems calibration. (Author)

  18. Highly restricted deletion of the SNORD116 region is implicated in Prader-Willi Syndrome.

    Science.gov (United States)

    Bieth, Eric; Eddiry, Sanaa; Gaston, Véronique; Lorenzini, Françoise; Buffet, Alexandre; Conte Auriol, Françoise; Molinas, Catherine; Cailley, Dorothée; Rooryck, Caroline; Arveiler, Benoit; Cavaillé, Jérome; Salles, Jean Pierre; Tauber, Maïthé

    2015-02-01

    The SNORD116 locus lies in the 15q11-13 region of paternally expressed genes implicated in Prader-Willi Syndrome (PWS), a complex disease accompanied by obesity and severe neurobehavioural disturbances. Cases of PWS patients with a deletion encompassing the SNORD116 gene cluster, but preserving the expression of flanking genes, have been described. We report a 23-year-old woman who presented clinical criteria of PWS, including the behavioural and nutritional features, obesity, developmental delay and endocrine dysfunctions with hyperghrelinemia. We found a paternally transmitted highly restricted deletion of the SNORD116 gene cluster, the shortest described to date (118 kb). This deletion was also present in the father. This finding in a human case strongly supports the current hypothesis that lack of the paternal SNORD116 gene cluster has a determinant role in the pathogenesis of PWS. Moreover, targeted analysis of the SNORD116 gene cluster, complementary to SNRPN methylation analysis, should be carried out in subjects with a phenotype suggestive of PWS.

  19. DETECTORS USED IN PARTICLE PHYSICS RESEARCH

    Energy Technology Data Exchange (ETDEWEB)

    Melissines, A. C.

    1963-10-15

    Detectors used in particle physics are discussed, and their specific properties are compared. With the pictorial'' devices are included nuclear emulsions, cloud and bubble chambers, and spark chambers. Included in the digital'' devices are counters, e.g., the Geiger counter, scintillation counters, solid-state detectors, Cherenkov counters, and spark counters. Sensitivity, resolving power, time resolutions, saturation level, and energy detection are discussed. (R.E.U.)

  20. Spectral and spatial resolution properties of photon counting X-ray detectors like the Medipix-Detector

    International Nuclear Information System (INIS)

    Korn, A.

    2007-01-01

    The Medipix detector is a hybrid photon counting X-ray detector, consisting of an ASIC and a semiconducting layer as the sensor. This makes the Medipix a direct converting detector. A special feature of the Medipix is a signal processing circuit in every single pixel. This circuit amplifies the input signal triggered by a photon and then transforms the pulse into a digital signal. This early stage digitalisation is one of the main advantages of the detector, since no dark currents are integrated into the signal. Furthermore, the energy information of each single photon is partly preserved. The high number of pixels lends the detector a wide dynamic range, starting from single counts up to a rate of 1010 photons per cm2 and second. Apart from the many advantages, there are still some problems with the detector. Some effects lead to a deterioration of the energy resolution as well as the spatial resolution. The main reasons for this are two effects occuring in the detector, charge sharing and backscattering inside the detector. This study investigates the influence of those two effects on both the energy and spatial resolution. The physical causes of these effects are delineated and their impact on the detector output is examined. In contrast to high energy photon detectors, the repulsion of the charge carriers drifting inside the sensor must not be neglected in a detailed model of X-ray detectors with an energy range of 5 keV-200 keV. For the simulation of the Medipix using Monte Carlo simulations, the software ROSI was augmented. The added features allow a detailed simulation of the charge distribution, using the relevant physical effects that alter the distribution width during the drift towards the sensor electrodes as well further influences on the detector output, including electronical noise, threshold noise or the geometry of the detector. The measured energy and spatial resolution of several different models of Medipix is compared to the simulated

  1. Adaptive Multiuser Detectors for DS-CDMA Systems

    Directory of Open Access Journals (Sweden)

    Paul Jean Etienne Jeszensky

    2006-02-01

    Full Text Available This work makes a review of the main Adaptives Multi-user Detectors (MuD-Adpt for Direct Sequence - Code Division Multiple Access (DS-CDMA systems. The MuD-Adpt based on Minimum Mean Square Error (MMSE and Decorrelator (MuD-Dec are focused. Multi-user detectors show great resistance to the near-far effect and combat effectively the Multiple Access Interference (MAI. Comparative numeric results characterize the substantial performance improvement of those detectors in relation to the matched filter conventional receiver (Conv.

  2. Detector and System Developments for LHC Detector Upgrades

    CERN Document Server

    Mandelli, Beatrice; Guida, Roberto; Rohne, Ole; Stapnes, Steinar

    2015-05-12

    The future Large Hadron Collider (LHC) Physics program and the consequent improvement of the LHC accelerator performance set important challenges to all detector systems. This PhD thesis delineates the studies and strategies adopted to improve two different types of detectors: the replacement of precision trackers with ever increasingly performing silicon detectors, and the improvement of large gaseous detector systems by optimizing their gas mixtures and operation modes. Within the LHC tracker upgrade programs, the ATLAS Insertable B-layer (IBL) is the first major upgrade of a silicon-pixel detector. Indeed the overall ATLAS Pixel Detector performance is expected to degrade with the increase of luminosity and the IBL will recover the performance by adding a fourth innermost layer. The IBL Detector makes use of new pixel and front-end electronics technologies as well as a novel thermal management approach and light support and service structures. These innovations required complex developments and Quality Ass...

  3. A comparative and combined study of EMIS and GPR detectors by the use of Independent Component Analysis

    DEFF Research Database (Denmark)

    Morgenstjerne, Axel; Karlsen, Brian; Larsen, Jan

    2005-01-01

    Independent Component Analysis (ICA) is applied to classify unexploded ordnance (UXO) on laboratory UXO test-field data, acquired by stand-off detection. The data are acquired by an Electromagnetic Induction Spectroscopy (EMIS) metal detector and a ground penetrating radar (GPR) detector. The metal...

  4. Prader-Willi syndrome and atypical submicroscopic 15q11-q13 deletions with or without imprinting defects.

    Science.gov (United States)

    Hassan, Maaz; Butler, Merlin G

    2016-11-01

    We report a 20 year follow up on a Caucasian female, now 26 years of age, with Prader-Willi syndrome (PWS) harboring an atypical 15q11-q13 submicroscopic deletion of 100-200 kb in size first detected in 1996 involving the imprinting center, SNRPN gene and surrounding region. PWS is a rare complex disorder caused by the loss of paternally expressed genes in the 15q11-q13 region. With high resolution chromosomal microarray and methylation - specific MLPA analysis, we updated the genetic findings on our patient and found a 209,819bp deletion including the SNURF-SNRPN gene complex which includes the imprinting center and the SNORD116 region. We compared with four other similarly reported individuals in the literature with atypical submicroscopic deletions within this region but without imprinting center involvement to better characterize the specific genetic lesions causing PWS clinical findings. Clinically, our patient met the diagnostic criteria of PWS including infantile hypotonia, a poor suck with feeding difficulties, global developmental delays and later food foraging, childhood obesity, small hands and skin picking. Small atypical deletions of comparable sizes were seen in the 15q11-q13 region in all five cases and similar behavioral/physical characteristics were found despite an imprinting defect in our patient. These results further support an overlapping critical deletion region involving the non-coding snoRNA SNORD116 in common in the five individuals playing a key role in contributing to the PWS phenotype. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  5. Comparison of radiation dose estimates, image noise, and scan duration in pediatric body imaging for volumetric and helical modes on 320-detector CT and helical mode on 64-detector CT

    International Nuclear Information System (INIS)

    Johnston, Jennifer H.; Podberesky, Daniel J.; Larson, David B.; Alsip, Christopher; Yoshizumi, Terry T.; Angel, Erin; Barelli, Alessandra; Toncheva, Greta; Egelhoff, John C.; Anderson-Evans, Colin; Nguyen, Giao B.; Frush, Donald P.; Salisbury, Shelia R.

    2013-01-01

    Advanced multidetector CT systems facilitate volumetric image acquisition, which offers theoretic dose savings over helical acquisition with shorter scan times. Compare effective dose (ED), scan duration and image noise using 320- and 64-detector CT scanners in various acquisition modes for clinical chest, abdomen and pelvis protocols. ED and scan durations were determined for 64-detector helical, 160-detector helical and volume modes under chest, abdomen and pelvis protocols on 320-detector CT with adaptive collimation and 64-detector helical mode on 64-detector CT without adaptive collimation in a phantom representing a 5-year-old child. Noise was measured as standard deviation of Hounsfield units. Compared to 64-detector helical CT, all acquisition modes on 320-detector CT resulted in lower ED and scan durations. Dose savings were greater for chest (27-46%) than abdomen/pelvis (18-28%) and chest/abdomen/pelvis imaging (8-14%). Noise was similar across scanning modes, although some protocols on 320-detector CT produced slightly higher noise. Dose savings can be achieved for chest, abdomen/pelvis and chest/abdomen/pelvis examinations on 320-detector CT compared to helical acquisition on 64-detector CT, with shorter scan durations. Although noise differences between some modes reached statistical significance, this is of doubtful diagnostic significance and will be studied further in a clinical setting. (orig.)

  6. Detector Unit

    CERN Multimedia

    1960-01-01

    Original detector unit of the Instituut voor Kernfysisch Onderzoek (IKO) BOL project. This detector unit shows that silicon detectors for nuclear physics particle detection were already developed and in use in the 1960's in Amsterdam. Also the idea of putting 'strips' onto the silicon for high spatial resolution of a particle's impact on the detector were implemented in the BOL project which used 64 of these detector units. The IKO BOL project with its silicon particle detectors was designed, built and operated from 1965 to roughly 1977. Detector Unit of the BOL project: These detectors, notably the ‘checkerboard detector’, were developed during the years 1964-1968 in Amsterdam, The Netherlands, by the Natuurkundig Laboratorium of the N.V. Philips Gloeilampen Fabrieken. This was done in close collaboration with the Instituut voor Kernfysisch Onderzoek (IKO) where the read-out electronics for their use in the BOL Project was developed and produced.

  7. Neutrino induced events in the MINOS detectors

    Energy Technology Data Exchange (ETDEWEB)

    Litchfield, Reuben Phillip [Univ. of Oxford (United Kingdom). Keble College

    2008-01-01

    The MINOS experiment is designed to study neutrino oscillations. It uses an accelerator generated beam of neutrinos and two detectors, the smaller at a distance of 1km and the larger at 735 km. By comparing the spectrum and flavour composition of the beam at the two detectors precise determinations of the oscillation parameters are possible. This thesis concentrates on the analysis of data from the larger Far Detector. By studying the spectrum of neutral current events it is possible to look for evidence of non-interacting 'sterile' neutrinos. The thesis describes how events are selected for this analysis, and a method for discriminating between charged current and neutral current events. The systematic uncertainties resulting from these cuts are evaluated. Several techniques for using Near Detector data to eliminate systematic uncertainties in the predicted Far Detector spectrum are compared. An oscillation analysis, based on the first year of MINOS data, uses the selected events to make a measurement of f{sub s}, the fraction of unseen neutrinos that are sterile. The measured value is fs = 0.07+0.32 at 68%C.L., and is consistent with the standard three-neutrino picture, which has no sterile neutrino.

  8. Comparison of morphological and conventional edge detectors in medical imaging applications

    Science.gov (United States)

    Kaabi, Lotfi; Loloyan, Mansur; Huang, H. K.

    1991-06-01

    Recently, mathematical morphology has been used to develop efficient image analysis tools. This paper compares the performance of morphological and conventional edge detectors applied to radiological images. Two morphological edge detectors including the dilation residue found by subtracting the original signal from its dilation by a small structuring element, and the blur-minimization edge detector which is defined as the minimum of erosion and dilation residues of the blurred image version, are compared with the linear Laplacian and Sobel and the non-linear Robert edge detectors. Various structuring elements were used in this study: regular 2-dimensional, and 3-dimensional. We utilized two criterions for edge detector's performance classification: edge point connectivity and the sensitivity to the noise. CT/MR and chest radiograph images have been used as test data. Comparison results show that the blur-minimization edge detector, with a rolling ball-like structuring element outperforms other standard linear and nonlinear edge detectors. It is less noise sensitive, and performs the most closed contours.

  9. Gastro-oesophageal reflux - an important causative factor of severe tooth wear in Prader-Willi syndrome?

    Science.gov (United States)

    Saeves, Ronnaug; Strøm, Finn; Sandvik, Leiv; Nordgarden, Hilde

    2018-04-23

    Prader-Willi syndrome (PWS) is the most common genetic human obesity syndrome and is characterized by hypotonia, endocrine disturbances, hyperphagia, obesity and mild mental retardation. Oral abnormalities, such as decreased salivary flow rates and extreme tooth wear, have also been described. Studies have shown a significant increase in reflux symptoms in individuals with obstuctive sleep apnoea syndrome and increased BMI, both of which are typical findings in PWS. Gastro-oesophageal reflux disease (GORD) has been identified in some individuals with PWS and is a significant intrinsic factor in dental tooth wear. The aim of this study was therefore to estimate the prevalence of GORD in adults and children and to evaluate a possible correlation between GORD and tooth wear in adults with PWS. They were all registered at the TAKO-centre. Twenty-nine individuals, 17 adults with a mean age of 32.6 years (range 18-48) and 12 children with a mean age of 8.8 years (range 3-17), agreed to undergo 24-hour oesophageal pH monitoring, and 90% of those enrolled managed to complete the examination. Four children and eleven adults were diagnosed with pathological gastro-oesophageal reflux, which is defined as acid exposure (pH less than 4) more than 3.6 or 4.3 percent of the time, respectively. Manometry performed in the adult group showed a pathologically high lower oesophageal sphincter pressure in four of the five individuals who had normal oesophageal pH values (pH under 4 less than 4.3% of the time). The two groups (reflux and non-reflux) were well balanced according to BMI, genotype, tooth grinding and hyposalivation. However, twice as many individuals in the reflux group as in the non-reflux group reported high consumption of acidic foods and drinks. Increased tooth wear was significantly correlated with GORD in the two groups (reflux n=6 and non-reflux n=6). The prevalence of gastro-oesophageal reflux is high in individuals with PWS. Tooth wear was strongly associated with

  10. Comparison of experimental and theoretical efficiency of HPGe X-ray detector

    International Nuclear Information System (INIS)

    Mohanty, B.P.; Balouria, P.; Garg, M.L.; Nandi, T.K.; Mittal, V.K.; Govil, I.M.

    2008-01-01

    The low energy high purity germanium (HPGe) detectors are being increasingly used for the quantitative estimation of elements using X-ray spectrometric techniques. The softwares used for quantitative estimation normally evaluate model based efficiency of detector using manufacturer supplied detector physical parameters. The present work shows that the manufacturer supplied detector parameters for low energy HPGe detectors need to be verified by comparing model based efficiency with the experimental ones. This is particularly crucial for detectors with ion implanted P type contacts

  11. Superconducting nano-strip particle detectors

    International Nuclear Information System (INIS)

    Cristiano, R; Ejrnaes, M; Casaburi, A; Zen, N; Ohkubo, M

    2015-01-01

    We review progress in the development and applications of superconducting nano-strip particle detectors. Particle detectors based on superconducting nano-strips stem from the parent devices developed for single photon detection (SSPD) and share with them ultra-fast response times (sub-nanosecond) and the ability to operate at a relatively high temperature (2–5 K) compared with other cryogenic detectors. SSPDs have been used in the detection of electrons, neutral and charged ions, and biological macromolecules; nevertheless, the development of superconducting nano-strip particle detectors has mainly been driven by their use in time-of-flight mass spectrometers (TOF-MSs) where the goal of 100% efficiency at large mass values can be achieved. Special emphasis will be given to this case, reporting on the great progress which has been achieved and which permits us to overcome the limitations of existing mass spectrometers represented by low detection efficiency at large masses and charge/mass ambiguity. Furthermore, such progress could represent a breakthrough in the field. In this review article we will introduce the device concept and detection principle, stressing the peculiarities of the nano-strip particle detector as well as its similarities with photon detectors. The development of parallel strip configuration is introduced and extensively discussed, since it has contributed to the significant progress of TOF-MS applications. (paper)

  12. Determining dose rate with a semiconductor detector - Monte Carlo calculations of the detector response

    Energy Technology Data Exchange (ETDEWEB)

    Nordenfors, C

    1999-02-01

    To determine dose rate in a gamma radiation field, based on measurements with a semiconductor detector, it is necessary to know how the detector effects the field. This work aims to describe this effect with Monte Carlo simulations and calculations, that is to identify the detector response function. This is done for a germanium gamma detector. The detector is normally used in the in-situ measurements that is carried out regularly at the department. After the response function is determined it is used to reconstruct a spectrum from an in-situ measurement, a so called unfolding. This is done to be able to calculate fluence rate and dose rate directly from a measured (and unfolded) spectrum. The Monte Carlo code used in this work is EGS4 developed mainly at Stanford Linear Accelerator Center. It is a widely used code package to simulate particle transport. The results of this work indicates that the method could be used as-is since the accuracy of this method compares to other methods already in use to measure dose rate. Bearing in mind that this method provides the nuclide specific dose it is useful, in radiation protection, since knowing what the relations between different nuclides are and how they change is very important when estimating the risks

  13. An unusual case of adolescent type 2 diabetes mellitus: Prader-Willi syndrome

    Directory of Open Access Journals (Sweden)

    Riyas Basheer

    2016-01-01

    Full Text Available Prader-Willi syndrome (PWS is a complex genetic disorder, characterized by neonatal hypotonia, developmental delay, short stature, childhood obesity, hypogonadism, and characteristic facial features. Here we report a 21-year-old male who presented with uncontrolled glycemic status. He was diagnosed to have diabetes mellitus at the age of 15 with osmotic symptoms - polyuria, polydipsia, and polyphagia. In the early period, after diagnosis, his blood sugars were reasonably controlled with oral hypoglycemic agents. However, a year back, he was switched onto insulin therapy due to secondary OHA failure. On examination, his body mass index was 36 kg/m 2 . He had bilateral gynecomastia, decreased biparietal diameter, almond shaped eyes with esotropia. He had hypogonadism and also had mild cognitive impairment. He did not have any proximal myopathy or other focal neurological deficits. Hormonal evaluation showed low testosterone and inappropriately normal fluorescence in situ hybridization suggestive of central hypogonadism. With fetal and neonatal hypotonia, delayed developmental milestones, hypogonadism, and early onset diabetes, he fulfilled the clinical criteria for the diagnosis of PWS. Multidisciplinary approach of clinicians together with family and social support are essential to bring out the optimal outcome for such syndromic cases.

  14. An unusual case of adolescent type 2 diabetes mellitus: Prader–Willi syndrome

    Science.gov (United States)

    Basheer, Riyas; Jalal, Muhammed Jasim Abdul; Gomez, Ramesh

    2016-01-01

    Prader–Willi syndrome (PWS) is a complex genetic disorder, characterized by neonatal hypotonia, developmental delay, short stature, childhood obesity, hypogonadism, and characteristic facial features. Here we report a 21-year-old male who presented with uncontrolled glycemic status. He was diagnosed to have diabetes mellitus at the age of 15 with osmotic symptoms – polyuria, polydipsia, and polyphagia. In the early period, after diagnosis, his blood sugars were reasonably controlled with oral hypoglycemic agents. However, a year back, he was switched onto insulin therapy due to secondary OHA failure. On examination, his body mass index was 36 kg/m2. He had bilateral gynecomastia, decreased biparietal diameter, almond shaped eyes with esotropia. He had hypogonadism and also had mild cognitive impairment. He did not have any proximal myopathy or other focal neurological deficits. Hormonal evaluation showed low testosterone and inappropriately normal fluorescence in situ hybridization suggestive of central hypogonadism. With fetal and neonatal hypotonia, delayed developmental milestones, hypogonadism, and early onset diabetes, he fulfilled the clinical criteria for the diagnosis of PWS. Multidisciplinary approach of clinicians together with family and social support are essential to bring out the optimal outcome for such syndromic cases. PMID:27453871

  15. An unusual case of adolescent type 2 diabetes mellitus: Prader-Willi syndrome.

    Science.gov (United States)

    Basheer, Riyas; Jalal, Muhammed Jasim Abdul; Gomez, Ramesh

    2016-01-01

    Prader-Willi syndrome (PWS) is a complex genetic disorder, characterized by neonatal hypotonia, developmental delay, short stature, childhood obesity, hypogonadism, and characteristic facial features. Here we report a 21-year-old male who presented with uncontrolled glycemic status. He was diagnosed to have diabetes mellitus at the age of 15 with osmotic symptoms - polyuria, polydipsia, and polyphagia. In the early period, after diagnosis, his blood sugars were reasonably controlled with oral hypoglycemic agents. However, a year back, he was switched onto insulin therapy due to secondary OHA failure. On examination, his body mass index was 36 kg/m(2). He had bilateral gynecomastia, decreased biparietal diameter, almond shaped eyes with esotropia. He had hypogonadism and also had mild cognitive impairment. He did not have any proximal myopathy or other focal neurological deficits. Hormonal evaluation showed low testosterone and inappropriately normal fluorescence in situ hybridization suggestive of central hypogonadism. With fetal and neonatal hypotonia, delayed developmental milestones, hypogonadism, and early onset diabetes, he fulfilled the clinical criteria for the diagnosis of PWS. Multidisciplinary approach of clinicians together with family and social support are essential to bring out the optimal outcome for such syndromic cases.

  16. Toxicity of phosphor esters: Willy Lange (1900-1976) and Gerda von Krueger (1907-after 1970).

    Science.gov (United States)

    Petroianu, G A

    2010-10-01

    In 1851 Williamson serendipitously discovered a new and efficient way to produce ethers using ethyl iodide and potassium salts. Based on this new synthetic approach, the Frenchman Philippe de Clermont and the Muscovite Wladimir Moschnin, both élèves of Adolphe Wurtz in his Paris School of Chemistry, achieved the synthesis of the first ester of pyrophosphoric acid (TEPP). de Clermont "tasted" the new compound and although TEPP is a potent cholinesterase inhibitor he failed to recognize its toxicity. Almost a century later, in 1932, Willy Lange (1900-1976) and his graduate student Gerda v. Krueger (1907-after 1970) described the toxicity of organophosphonates. While the classic paper of the two "Uber Ester der Monofluorphosphorsäure." is cited by almost everybody working in the field, little is known about Lange and almost nothing about v. Krueger. This brief communication attempts to shed some light on the life of both.

  17. Computer-assisted 3D reconstruction of the terminal branches of the cerebral arteries. Pt. 3. Posterior cerebral artery and circle of Willis

    International Nuclear Information System (INIS)

    Gloger, S.; Gloger, A.; Vogt, H.; Kretschmann, H.J.

    1994-01-01

    We present a three-dimensional anatomical computer model of the terminal branches of the posterior cerebral artery and circle of Willis, acquired from equidistant serial anatomical slices of three brains. The reconstructions provide a clear picture from all angles of the complicated course of the terminal branches of the cerebral arteries. This can help to identify the arteries in conventional and magnetic resonance angiography. Our rendition of the cerebral arteries can be matched with CT, MR and PET images to indicate the areas of extension of the individual branches, allowing neuromorphological and functional correlations. (orig.)

  18. Computer-assisted 3D reconstruction of the terminal branches of the cerebral arteries. Pt. 3. Posterior cerebral artery and circle of Willis

    Energy Technology Data Exchange (ETDEWEB)

    Gloger, S. (Dept. of Neuroanatomy, Hannover Medical School (Germany)); Gloger, A. (Dept. of Neuroanatomy, Hannover Medical School (Germany)); Vogt, H. (Dept. of Neuroanatomy, Hannover Medical School (Germany)); Kretschmann, H.J. (Dept. of Neuroanatomy, Hannover Medical School (Germany))

    1994-05-01

    We present a three-dimensional anatomical computer model of the terminal branches of the posterior cerebral artery and circle of Willis, acquired from equidistant serial anatomical slices of three brains. The reconstructions provide a clear picture from all angles of the complicated course of the terminal branches of the cerebral arteries. This can help to identify the arteries in conventional and magnetic resonance angiography. Our rendition of the cerebral arteries can be matched with CT, MR and PET images to indicate the areas of extension of the individual branches, allowing neuromorphological and functional correlations. (orig.)

  19. Comparative study of new 130mm diameter fast photomultipliers for neutron detectors

    International Nuclear Information System (INIS)

    Moszynski, M.; Costa, G.J.; Guillaume, G.; Heusch, B.; Huck, A.; Mouatassim, S.

    1991-01-01

    The present paper is a summary of the test measurements carried out using new 130 mm diameter fast photomultiplier tubes manufactured by Philips (France), EMI (England) and Hamamatsu (Japan), along with a comparison to the results obtained with the well known XP 2041 Philips model. These tubes will be used in large size neutron detectors

  20. Rotating detectors and Mach's principle

    Energy Technology Data Exchange (ETDEWEB)

    Paola, R.D.M. de; Svaiter, N.F

    2000-08-01

    In this work we consider a quantum version of Newton{sup s} bucket experiment in a fl;at spacetime: we take an Unruh-DeWitt detector in interaction with a real massless scalar field. We calculate the detector's excitation rate when it is uniformly rotating around some fixed point and the field is prepared in the Minkowski vacuum and also when the detector is inertial and the field is in the Trocheries-Takeno vacuum state. These results are compared and the relations with Mach's principle are discussed. (author)

  1. Detector response theory and its applications

    International Nuclear Information System (INIS)

    Keijzer, J.

    1992-11-01

    Some methods to describe the dynamics of fission reactors are investigated. First the reactivity of a reactor is regarded. The values of an exact calculation of the reactivity are compared with values obtained by first-order perturbation theory. Then a description of the point reactor kinetic theory and the detector response theory is given. A comparison of the two methods is made, using models of some well defined perturbations. Two of the perturbations are such that a physical movement of some absorber is regarded. A new way of modelling these moving objects is proposed. The result of the point reactor kinetic theory and the detecor response theory did not differ too much for perturbations which were far from the detector position. Locally however point reactor kinetic theory was not, in contrast with detector response theory, able to produce reliable results. The results of these calculations are to be compared with experiments, which will be performed later. (orig.)

  2. A Weibull distribution accrual failure detector for cloud computing.

    Science.gov (United States)

    Liu, Jiaxi; Wu, Zhibo; Wu, Jin; Dong, Jian; Zhao, Yao; Wen, Dongxin

    2017-01-01

    Failure detectors are used to build high availability distributed systems as the fundamental component. To meet the requirement of a complicated large-scale distributed system, accrual failure detectors that can adapt to multiple applications have been studied extensively. However, several implementations of accrual failure detectors do not adapt well to the cloud service environment. To solve this problem, a new accrual failure detector based on Weibull Distribution, called the Weibull Distribution Failure Detector, has been proposed specifically for cloud computing. It can adapt to the dynamic and unexpected network conditions in cloud computing. The performance of the Weibull Distribution Failure Detector is evaluated and compared based on public classical experiment data and cloud computing experiment data. The results show that the Weibull Distribution Failure Detector has better performance in terms of speed and accuracy in unstable scenarios, especially in cloud computing.

  3. Beneficial effects of growth hormone treatment on cognition in children with Prader-Willi syndrome: a randomized controlled trial and longitudinal study.

    Science.gov (United States)

    Siemensma, Elbrich P C; Tummers-de Lind van Wijngaarden, Roderick F A; Festen, Dederieke A M; Troeman, Zyrhea C E; van Alfen-van der Velden, A A E M Janielle; Otten, Barto J; Rotteveel, Joost; Odink, Roelof J H; Bindels-de Heus, G C B Karen; van Leeuwen, Mariette; Haring, Danny A J P; Oostdijk, Wilma; Bocca, Gianni; Mieke Houdijk, E C A; van Trotsenburg, A S Paul; Hoorweg-Nijman, J J Gera; van Wieringen, Hester; Vreuls, René C F M; Jira, Petr E; Schroor, Eelco J; van Pinxteren-Nagler, Evelyn; Willem Pilon, Jan; Lunshof, L Bert; Hokken-Koelega, Anita C S

    2012-07-01

    Knowledge about the effects of GH treatment on cognitive functioning in children with Prader-Willi syndrome (PWS) is limited. Fifty prepubertal children aged 3.5 to 14 yr were studied in a randomized controlled GH trial during 2 yr, followed by a longitudinal study during 4 yr of GH treatment. Cognitive functioning was measured biennially by short forms of the WPPSI-R or WISC-R, depending on age. Total IQ (TIQ) score was estimated based on two subtest scores. During the randomized controlled trial, mean sd scores of all subtests and mean TIQ score remained similar compared to baseline in GH-treated children with PWS, whereas in untreated controls mean subtest sd scores and mean TIQ score decreased and became lower compared to baseline. This decline was significant for the Similarities (P = 0.04) and Vocabulary (P = 0.03) subtests. After 4 yr of GH treatment, mean sd scores on the Similarities and Block design subtests were significantly higher than at baseline (P = 0.01 and P = 0.03, respectively), and scores on Vocabulary and TIQ remained similar compared to baseline. At baseline, children with a maternal uniparental disomy had a significantly lower score on the Block design subtest (P = 0.01) but a larger increment on this subtest during 4 yr of GH treatment than children with a deletion. Lower baseline scores correlated significantly with higher increases in Similarities (P = 0.04) and Block design (P deficit had more benefit from GH treatment.

  4. New pixelized Micromegas detector for the COMPASS experiment

    International Nuclear Information System (INIS)

    Neyret, D; Anfreville, M; Bedfer, Y; Burtin, E; D'Hose, N; Giganon, A; Kunne, F; Magnon, A; Marchand, C; Paul, B; Platchkov, S; Vandenbroucke, M; Ketzer, B; Konorov, I

    2009-01-01

    New Micromegas (Micro-mesh gaseous detectors) are being developed in view of the future physics projects planned by the COMPASS collaboration at CERN. Several major upgrades compared to present detectors are being studied: detectors standing five times higher luminosity with hadron beams, detection of beam particles (flux up to a few hundred of kHz/mm 2 , 10 times larger than for the present detectors) with pixelized read-out in the central part, light and integrated electronics, and improved robustness. Studies were done with the present detectors moved in the beam, and two first pixelized prototypes are being tested with muon and hadron beams in real conditions at COMPASS. We present here this new project and report on two series of tests, with old detectors moved into the beam and with pixelized prototypes operated in real data taking condition with both muon and hadron beams.

  5. The Developmental Trajectory of Self-Injurious Behaviours in Individuals with Prader Willi Syndrome, Autism Spectrum Disorder and Intellectual Disability

    Directory of Open Access Journals (Sweden)

    Lauren J. Rice

    2016-02-01

    Full Text Available In the present study we examined the nature and developmental trajectory of self-injurious behaviour in Prader Willi syndrome (PWS and autism spectrum disorder (ASD. The development of interventions is greatly aided by understanding gene to behaviour pathways, and this requires an accurate description of the behaviour phenotype, that is, which types and natural history of self-injurious behaviour are more common in PWS and ASD and which are shared with other forms of developmental disability. Self-injury displayed by individuals with PWS and individuals with ASD was compared with that reported in a group of individuals with intellectual disability due to mixed aetiology (ID group. Three self-injurious behaviours (head banging, skin-picking and hitting and/or biting self were measured on five occasions over 18 years using the Developmental Behaviour Checklist (DBC a well-validated caregiver report measure. Rates of skin picking were higher in individuals with PWS and hitting and/or biting self was higher in individuals with ASD compared to the ID group. Rates of head banging were similar across the three groups. Over time, skin-picking and head banging increased with age for individuals with ASD and hitting and/or biting self increased for the PWS group. In the PWS and mixed ID groups head banging decreased with age. These findings suggest that the typology and developmental trajectories of self-injurious behaviours differ between those with PWS and ASD.

  6. Discrimination of binary coherent states using a homodyne detector and a photon number resolving detector

    DEFF Research Database (Denmark)

    Wittmann, Christoffer; Andersen, Ulrik Lund; Takeoka, Masahiro

    2010-01-01

    We investigate quantum measurement strategies capable of discriminating two coherent states probabilistically with significantly smaller error probabilities than can be obtained using nonprobabilistic state discrimination. We apply a postselection strategy to the measurement data of a homodyne...... detector as well as a photon number resolving detector in order to lower the error probability. We compare the two different receivers with an optimal intermediate measurement scheme where the error rate is minimized for a fixed rate of inconclusive results. The photon number resolving (PNR) receiver...

  7. Dosimetric characterization of a commercial two-dimensional array detector; Caracterizacao dosimetrica de um detector matricial bidimensional comercial

    Energy Technology Data Exchange (ETDEWEB)

    Gialluisi, Bruno L.; Santos, Gabriela R. dos; Sales, Camila P. de; Resende, Guilherme R.A.; Habitzreuter, Angela B.; Rodrigues, Laura N., E-mail: brunogialluisi@gmail.com [Universidade de Sao Paulo (HCFMRP/USP), Sao Paulo, SP (Brazil). Hospital das Clinicas. Servico de Radioterapia

    2013-04-15

    This paper investigates the dosimetric characteristics and performance of an array detector commercially available. The device is the I'mRT MatriXX® which is a two-dimensional detector array used in the verification of complex radiotherapy plans. It consists of 1,020 parallel plate ion chamber arranged in a 32x32 grid. Dose linearity was studied and its response was linear within the range of 5 to 1000 MU (R{sup 2} = 1). Dose rate dependence showed a maximum deviation of 0,62% comparatively with readings to 320 cGy/min. The detector stability was verified through repeated irradiations. Output factors matched well with measurements made with a Farmer chamber with an average deviation of 1,54%. The detector's effective point of measurement was determined and the inverse square law was also verified with a percentage deviation smaller than 3%. The results show that this detector can be used for quality control in IMRT thus reducing the time spent in the dosimetric verification of radiation fields. (author)

  8. Dosimetric characterization of a commercial two-dimensional array detector; Caracterizacao dosimetrica de um detector matricial bidimensional comercial

    Energy Technology Data Exchange (ETDEWEB)

    Gialluisi, Bruno L.; Santos, Gabriela R. dos; Sales, Camila P. de; Resende, Guilherme R.A.; Habitzreuter, Angela B.; Rodrigues, Laura N., E-mail: brunogialluisi@gmail.com [Universidade de Sao Paulo (HCFMRP/USP), Sao Paulo, SP (Brazil). Hospital das Clinicas. Servico de Radioterapia

    2013-04-15

    This paper investigates the dosimetric characteristics and performance of an array detector commercially available. The device is the I'mRT MatriXX® which is a two-dimensional detector array used in the verification of complex radiotherapy plans. It consists of 1,020 parallel plate ion chamber arranged in a 32x32 grid. Dose linearity was studied and its response was linear within the range of 5 to 1000 MU (R{sup 2} = 1). Dose rate dependence showed a maximum deviation of 0,62% comparatively with readings to 320 cGy/min. The detector stability was verified through repeated irradiations. Output factors matched well with measurements made with a Farmer chamber with an average deviation of 1,54%. The detector's effective point of measurement was determined and the inverse square law was also verified with a percentage deviation smaller than 3%. The results show that this detector can be used for quality control in IMRT thus reducing the time spent in the dosimetric verification of radiation fields. (author)

  9. Modelling of performance of the ATLAS SCT detector

    International Nuclear Information System (INIS)

    Kazi, S.

    2000-01-01

    Full text: The ATLAS detector being built at LHC will use the SCT (semiconductor tracking) module for particle tracking in the inner core of the detector. An analytical/numerical model of the discriminator threshold dependence and the temperature dependence of the SCT module was derived. Measurements were conducted on the performance of the SCT module versus temperature and these results were compared with the predictions made by the model. The affect of radiation damage of the SCT detector was also investigated. The detector will operate for approximately 10 years so a study was carried out on the effects of the 10 years of radiation exposure to the SCT

  10. Foam radiators for transition radiation detectors

    International Nuclear Information System (INIS)

    Chernyatin, V.; Dolgoshein, B.; Gavrilenko, I.; Potekhin, M.; Romaniouk, A.; Sosnovtsev, V.

    1993-01-01

    A wide variety of foam radiators, potentially useful in the design of a transition radiation detector, the possible particle identification tool in collider experiments, have been tested in the beam. Various characteristics of these radiators are compared, and the conclusion is reached that certain brands of polyethylene foam are best suited for use in the detector. Comparison is made with a 'traditional' radiator, which is a periodic structure of plastic foils. (orig.)

  11. Silicon detectors

    International Nuclear Information System (INIS)

    Klanner, R.

    1984-08-01

    The status and recent progress of silicon detectors for high energy physics is reviewed. Emphasis is put on detectors with high spatial resolution and the use of silicon detectors in calorimeters. (orig.)

  12. Performance of B-10 based detectors

    Energy Technology Data Exchange (ETDEWEB)

    Boucher, Mathieu; Anderson, Tom; Johnson, Nathan; Mckinny, Kevin; Mcpheeters, Matthew [GE Measurement and Control - Reuter-Stokes, Twinsburg, Ohio (United States)

    2015-07-01

    Helium-3 gas-filled detectors have been used in nuclear safeguards applications, in homeland security neutron detection modules and in research for over 30 years. With the current shortage of {sup 3}He gas, GE's Reuter-Stokes business developed a {sup 10}B lined proportional counter and a {sup 10}B hybrid detector, in which a small amount of {sup 3}He is added to a 10B detector to enhance the neutron sensitivity. In 2010, GE's Reuter-Stokes successfully developed a commercial alternative to 3He gas-filled detectors for homeland security neutron detection modules based on 10B lined proportional counters. We will present the concept behind the {sup 10}B neutron detection modules, as drop-in replacement to existing 3He neutron detection modules deployed, and the timeline and development needed to get a fully commercial application. To ensure the highest quality, each {sup 10}B neutron detection unit is put through a series of tests: temperature cycles from -40 deg. C to +55 deg. C, vibration testing at levels up to 2.5 g from 10 Hz to 50 Hz in every direction, neutron sensitivity reaching up to 4.5 cps/(ng {sup 252}CF at 2 m), and gamma insensitivity with field reaching 1 Sv/hr. In 2013, GE's Reuter-Stokes developed the B10Plus+{sup R} detector, in which a small amount of {sup 3}He is added to a {sup 10}B lined proportional counter. Depending on the amount of {sup 3}He added, the B10Plus+{sup R} can more than double the neutron sensitivity compared to a {sup 10}B lined proportional counter. {sup 10}B lined proportional counters and B10Plus+{sup R} have excellent gamma rejection and excellent performance even at very high neutron flux. The gamma rejection and high neutron flux performance of these detectors are comparable, if not better, than traditional {sup 3}He proportional counters. GE's Reuter-Stokes business modelled, designed, built and tested prototype coincidence counters using the {sup 10}B lined detectors and the {sup 10}B hybrid

  13. Metal-semiconductor, composite radiation detectors

    International Nuclear Information System (INIS)

    Orvis, W.J.; Yee, J.H.; Fuess, D.

    1992-12-01

    In 1989, Naruse and Hatayama of Toshiba published a design for an increased efficiency x-ray detector. The design increased the efficiency of a semiconductor detector by interspersing layers of high-z metal within it. Semiconductors such as silicon make good, high-resolution radiation detectors, but they have low efficiency because they are low-z materials (z = 14). High-z metals, on the other hand, are good absorbers of high-energy photons. By interspersing high-z metal layers with semiconductor layers, Naruse and Hatayama combined the high absorption efficiency of the high-z metals with the good detection capabilities of a semiconductor. This project is an attempt to use the same design to produce a high-efficiency, room temperature gamma ray detector. By their nature, gamma rays require thicker metal layers to efficiently absorb them. These thicker layers change the behavior of the detector by reducing the resolution, compared to a solid state detector, and shifting the photopeak by a predictable amount. During the last year, the authors have procured and tested a commercial device with operating characteristics similar to those of a single layer of the composite device. They have modeled the radiation transport in a multi-layered device, to verify the initial calculations of layer thickness and composition. They have modeled the electrostatic field in different device designs to locate and remove high-field regions that can cause device breakdown. They have fabricated 14 single layer prototypes

  14. Neutron energy response measurement of scintillation detectors

    International Nuclear Information System (INIS)

    Yang Hongqiong; Peng Taiping; Yang Jianlun; Tang Zhengyuan; Yang Gaozhao; Li Linbo; Hu Mengchun; Wang Zhentong; Zhang Jianhua; Li Zhongbao; Wang Lizong

    2004-01-01

    Neutron sensitivities of detectors composed of plastic scintillator ST401, ST1422, ST1423 and phyotomultiplier tube in primary energy range of fission neutron are calibrated by direct current. The energy response curve of the detectors is obtained in this experiment. The experimental result has been compared with the theoretical calculation and they are in agreement within measuring uncertainty. (authors)

  15. Assistência multiprofissional em unidade de terapia intensiva ao paciente portador de síndrome de Prader-Willi: um enfoque odontológico

    Directory of Open Access Journals (Sweden)

    Juliana Santiago Setti

    2012-03-01

    Full Text Available A síndrome de Prader-Willi (SPW é uma doença neurocomportamental genética que afeta o desenvolvimento da criança, resultando em obesidade, estatura reduzida, hipotonia, distúrbios endócrinos e déficit cognitivo que podem comprometer a integridade da cavidade oral. O presente estudo tem como finalidade apresentar um caso de paciente branco, masculino, 15 anos de idade portador da referida síndrome cujo exame clínico intra-oral evidenciou presença de placa bacteriana, gengivite, má-oclusão, salivação viscosa e múltiplas lesões ulceradas em lábio, mucosa jugal, gengiva inserida, dorso e ventre lingual e lesões papulares ulceradas em borda lateral da língua. Após realização de biópsia excisional, foi constatada a presença de lesão herpética em cavidade oral e lesões cutâneas típicas do herpes que foram associadas a possível causa de encefalite herpética. Assim, observou-se que grande parcela dos efeitos deletérios da SPW podem ser amenizados com o diagnóstico correto e intervenções terapêuticas e educacionais precoces, sendo importante a atuação de uma equipe multiprofissional integrada e o desenvolvimento de protocolos assistenciais para melhor manejo dos pacientes portadores da síndrome de Prader-Willi.

  16. A DBN based anomaly targets detector for HSI

    Science.gov (United States)

    Ma, Ning; Wang, Shaojun; Yu, Jinxiang; Peng, Yu

    2017-10-01

    Due to the assumption that Hyperspectral image (HSI) should conform to Gaussian distribution, traditional Mahalanobis distance-based anomaly targets detectors perform poor because the assumption may not always hold. In order to solve those problems, a deep learning based detector, Deep Belief Network(DBN) anomaly detector(DBN-AD), was proposed to fit the unknown distribution of HSI by energy modeling, the reconstruction errors of this encode-decode processing are used for discriminating the anomaly targets. Experiments are implemented on real and synthesized HSI dataset which collection by Airborne Visible Infra-Red Imaging Spectrometer (AVIRIS). Comparing to classic anomaly detector, the proposed method shows better performance, it performs about 0.17 higher in Area Under ROC Curve (AUC) than that of Reed-Xiaoli detector(RXD) and Kernel-RXD (K-RXD).

  17. Characterization of 3D-DDTC detectors on p-type substrates

    CERN Document Server

    Betta, G -F Dalla; Bosisio, Luciano; Darbo, Giovanni; Gabos, Paolo; Gemme, Claudia; Koehler, Michael; La Rosa, Alessandro; Parzefall, Ulrich; Pernegger, Heinz; Piemonte, Claudio; Povoli, Marco; Rachevskaia, Irina; Ronchin, Sabina; Wiik, Liv; Zoboli, Aanrea; Zorzi, Nicola

    2009-01-01

    We report on the electrical and functional characterization of 3D Double-side, Double-Type-Column (3D- DDTC) detectors fabricated on p-type substrates. Results relevant to detectors in the diode, strip and pixel configurations are presented, and demonstrate a clear improvement in the charge collection performance compared to the first prototypes of these detectors.

  18. Quality control measurements for digital x-ray detectors

    Energy Technology Data Exchange (ETDEWEB)

    Marshall, N W [Department of Radiology, University Hospitals Leuven, 49 Herenstraat, 3000 Leuven (Belgium); Mackenzie, A [National Co-ordinating Centre for the Physics of Mammography, Medical Physics, Level B, St Luke' s Wing, The Royal Surrey County Hospital NHS Trust, Egerton Road, Guildford, GU2 7XX (United Kingdom); Honey, I D, E-mail: nicholas.marshall@uz.kuleuven.ac.be [Department of Medical Physics, Floor 3, Henriette Raphael House, Guy' s and St Thomas' Hospital, London, SE1 9RT (United Kingdom)

    2011-02-21

    This paper describes a digital radiography (DR) quality control protocol for DR detectors from the forthcoming report from the Institute of Physics and Engineering in Medicine (IPEM). The protocol was applied to a group of six identical caesium iodide (CsI) digital x-ray detectors to assess reproducibility of methods, while four further detectors were assessed to examine the wider applicability. Twelve images with minimal spatial frequency processing are required, from which the detector response, lag, modulation transfer function (MTF), normalized noise power spectrum (NNPS) and threshold contrast-detail (c-d) detectability are calculated. The x-ray spectrum used was 70 kV and 1 mm added copper filtration, with a target detector air kerma of 2.5 {mu}Gy for the NNPS and c-d results. In order to compare detector performance with previous imaging technology, c-d data from four screen/film systems were also acquired, at a target optical density of 1.5 and an average detector air kerma of 2.56 {mu}Gy. The DR detector images were typically acquired in 20 min, with a further 45 min required for image transfer and analysis. The average spatial frequency for the 50% point of the MTF for six identical detectors was 1.29 mm{sup -1} {+-} 0.05 (3.9% coefficient of variation (cov)). The air kerma set for the six systems was 2.57 {mu}Gy {+-} 0.13 (5.0% cov) and the NNPS at this air kerma was 1.42 x 10{sup -5} mm{sup 2} (6.5% cov). The detective quantum efficiency (DQE) measured for the six identical detectors was 0.60 at 0.5 mm{sup -1}, with a maximum cov of 10% at 2.9 mm{sup -1}, while the average DQE was 0.56 at 0.5 mm{sup -1} for three CsI detectors from three different manufacturers. Comparable c-d performance was found for these detectors (5.9% cov) with an average threshold contrast of 0.46% for 11 mm circular discs. The average threshold contrast for the S/F systems was 0.70% at 11 mm, indicating superior imaging performance for the digital systems. The protocol was found

  19. Performance of a Small Anode Germanium Well detector

    International Nuclear Information System (INIS)

    Adekola, A.S.; Colaresi, J.; Douwen, J.; Mueller, W.F.; Yocum, K.M.

    2015-01-01

    The performance of Small Anode Germanium (SAGe) Well detector [1] has been evaluated for a range of sample sizes and geometries counted inside the well, on the end cap or in Marinelli beakers. The SAGe Well is a new type of low capacitance germanium well detector manufactured using small anode technology. The detector has similar energy resolution performance to semi-planar detectors, and offers significant improvement over the Coaxial and existing Well detectors. Resolution performance of 0.75 keV Full Width at Half Maxiumum (FWHM) at 122 keV γ-ray energy and resolution of 2.0–2.3 keV FWHM at 1332 keV γ-ray energy are guaranteed. Such outstanding resolution performance will benefit environmental applications in revealing the detailed radionuclide content of samples, particularly at low energy, and will enhance the detection sensitivity resulting in reduced counting time. This paper reports the counting performance of SAGe Well detector for range of sample sizes and geometries and how it compares to other detector types

  20. Performance of a Small Anode Germanium Well detector

    Energy Technology Data Exchange (ETDEWEB)

    Adekola, A.S., E-mail: aderemi.adekola@canberra.com; Colaresi, J.; Douwen, J.; Mueller, W.F.; Yocum, K.M.

    2015-06-01

    The performance of Small Anode Germanium (SAGe) Well detector [1] has been evaluated for a range of sample sizes and geometries counted inside the well, on the end cap or in Marinelli beakers. The SAGe Well is a new type of low capacitance germanium well detector manufactured using small anode technology. The detector has similar energy resolution performance to semi-planar detectors, and offers significant improvement over the Coaxial and existing Well detectors. Resolution performance of 0.75 keV Full Width at Half Maxiumum (FWHM) at 122 keV γ-ray energy and resolution of 2.0–2.3 keV FWHM at 1332 keV γ-ray energy are guaranteed. Such outstanding resolution performance will benefit environmental applications in revealing the detailed radionuclide content of samples, particularly at low energy, and will enhance the detection sensitivity resulting in reduced counting time. This paper reports the counting performance of SAGe Well detector for range of sample sizes and geometries and how it compares to other detector types.

  1. Mobility and powering of large detectors. Moving large detectors

    International Nuclear Information System (INIS)

    Thompson, J.

    1977-01-01

    The possibility is considered of moving large lepton detectors at ISABELLE for readying new experiments, detector modifications, and detector repair. A large annex (approximately 25 m x 25 m) would be built adjacent to the Lepton Hall separated from the Lepton Hall by a wall of concrete 11 m high x 12 m wide (for clearance of the detector) and approximately 3 m thick (for radiation shielding). A large pad would support the detector, the door, the cryogenic support system and the counting house. In removing the detector from the beam hall, one would push the pad into the annex, add a dummy beam pipe, bake out the beam pipe, and restack and position the wall on a small pad at the door. The beam could then operate again while experimenters could work on the large detector in the annex. A consideration and rough price estimate of various questions and proposed solutions are given

  2. A reduced-energy intake, well-balanced diet improves weight control in children with Prader-Willi syndrome

    Science.gov (United States)

    Miller, J. L.; Lynn, C. H.; Shuster, J.; Driscoll, D. J.

    2014-01-01

    Background Children with Prader-Willi syndrome (PWS) have a predictable pattern of weight gain, with obesity beginning in early childhood and worsening as they get older and hyperphagia increases. Data on the most effective dietary modifications are scant and primarily anecdotal. As part of a longitudinal study investigating the natural history of PWS, we evaluated the effect of a well-balanced, energy-restricted diet on body composition and weight in young children with PWS. Methods Sixty-three children, aged 2–10 years, with genetically proven PWS participated in the present study. These children had measurements of body composition by dual-energy X-ray absorptiometry and resting energy expenditure (REE), as well as a 3-day diet history analysis both before and after intervention. Energy calculations were based on the individual's REE, with the recommendation that the macronutrients of the diet consist of 30% fat, 45% carbohydrates and 25% protein, with at least 20 g of fibre per day. Results Thirty-three families adhered to our dietary recommendations for both energy intake and macronutrient distribution. Those 33 children had lower body fat (19.8% versus 41.9%; P diet. Those who followed our recommendations also had a lower respiratory quotient (0.84 versus 0.95; P = 0.002). Conclusions Our recommendation for an energy-restricted diet with a well-balanced macronutrient composition and fibre intake improves both weight and body composition in children with PWS compared to a simple energy-restricted diet. PMID:23078343

  3. Altered functional resting-state hypothalamic connectivity and abnormal pituitary morphology in children with Prader-Willi syndrome.

    Science.gov (United States)

    Lukoshe, Akvile; van Dijk, Suzanne E; van den Bosch, Gerbrich E; van der Lugt, Aad; White, Tonya; Hokken-Koelega, Anita C

    2017-01-01

    Prader-Willi syndrome (PWS) is a complex neurodevelopmental disorder, characterized by endocrine problems and hyperphagia, indicating hypothalamic-pituitary dysfunction. However, few studies have explored the underlying neurobiology of the hypothalamus and its functional connectivity with other brain regions. Thus, the aim of this study was to examine the anatomical differences of the hypothalamus, mammillary bodies, and pituitary gland as well as resting state functional connectivity of the hypothalamus in children with PWS. Twenty-seven children with PWS (13 DEL, 14 mUPD) and 28 typically developing children were included. Manual segmentations by a blinded investigator were performed to determine the volumes of the hypothalamus, mammillary bodies, and pituitary gland. In addition, brain-wide functional connectivity analysis was performed using the obtained masks of the hypothalamus. Children with PWS showed altered resting state functional connectivity between hypothalamus and right and left lateral occipital complex, compared to healthy controls. In addition, children with PWS had on average a 50% smaller pituitary volume, an irregular shape of the pituitary, and a longer pituitary stalk. Pituitary volume did not increase in volume during puberty in PWS. No volumetric differences in the hypothalamus and mammillary bodies were found. In all subjects, the posterior pituitary bright spot was observed. We report altered functional hypothalamic connectivity with lateral occipital complexes in both hemispheres, which are implicated in response to food and reward system, and absence of connectivity might therefore at least partially contribute to the preoccupation with food in PWS.

  4. Model calculations for electrochemically etched neutron detectors

    International Nuclear Information System (INIS)

    Pitt, E.; Scharmann, A.; Werner, B.

    1988-01-01

    Electrochemical etching has been established as a common method for visualisation of nuclear tracks in solid state nuclear track detectors. Usually the Mason equation, which describes the amplification of the electrical field strength at the track tip, is used to explain the treeing effect of electrochemical etching. The yield of neutron-induced tracks from electrochemically etched CR-39 track detectors was investigated with respect to the electrical parameters. A linear dependence on the response from the macroscopic field strength was measured which could not be explained by the Mason equation. It was found that the reality of a recoil proton track in the detector does not fit the boundary conditions which are necessary when the Mason equation is used. An alternative model was introduced to describe the track and detector geometry in the case of a neutron track detector. The field strength at the track tip was estimated with this model and compared with the experimental data, yielding good agreement. (author)

  5. Parametric Adaptive Radar Detector with Enhanced Mismatched Signals Rejection Capabilities

    Directory of Open Access Journals (Sweden)

    Liu Bin

    2010-01-01

    Full Text Available We consider the problem of adaptive signal detection in the presence of Gaussian noise with unknown covariance matrix. We propose a parametric radar detector by introducing a design parameter to trade off the target sensitivity with sidelobes energy rejection. The resulting detector merges the statistics of Kelly's GLRT and of the Rao test and so covers Kelly's GLRT and the Rao test as special cases. Both invariance properties and constant false alarm rate (CFAR behavior for this detector are studied. At the analysis stage, the performance of the new receiver is assessed and compared with several traditional adaptive detectors. The results highlight better rejection capabilities of this proposed detector for mismatched signals. Further, we develop two two-stage detectors, one of which consists of an adaptive matched filter (AMF followed by the aforementioned detector, and the other is obtained by cascading a GLRT-based Subspace Detector (SD and the proposed adaptive detector. We show that the former two-stage detector outperforms traditional two-stage detectors in terms of selectivity, and the latter yields more robustness.

  6. Mental and motor development before and during growth hormone treatment in infants and toddlers with Prader-Willi syndrome.

    Science.gov (United States)

    Festen, D A M; Wevers, M; Lindgren, A C; Böhm, B; Otten, B J; Wit, J M; Duivenvoorden, H J; Hokken-Koelega, A C S

    2008-06-01

    Prader-Willi syndrome (PWS) is a neurogenetic disorder characterized by muscular hypotonia, psychomotor delay, feeding difficulties and failure to thrive in infancy. GH treatment improves growth velocity and body composition. Research on the effects of GH on psychomotor development in infants with PWS is limited. To evaluate psychomotor development in PWS infants and toddlers during GH treatment compared to randomized controls. Forty-three PWS infants were evaluated at baseline. Twenty-nine of them were randomized into a GH group (n = 15) receiving 1 mg/m(2)/day GH or a non-GH-treated control group (n = 14). At baseline and after 12 months of follow-up, analysis with Bayley Scales of Infant Development II (BSID-II) was performed. Data were converted to percentage of expected development for age (%ed), and changes during follow-up were calculated. Infants in the GH group had a median age of 2.3 years [interquartile range (IQR) 1.7-3.0] and in the control group of 1.5 years (IQR 1.2-2.7) (P = 0.17). Both mental and motor development improved significantly during the first year of study in the GH group vs. the control group: median (IQR) change was +9.3% (-5.3 to 13.3) vs.-2.9% (-8.1 to 4.9) (P development and +11.2% (-4.9 to 22.5) vs.-18.5% (-27.9 to 1.8) (P development, respectively. One year of GH treatment significantly improved mental and motor development in PWS infants compared to randomized controls.

  7. Monitoring radiation damage in the ATLAS pixel detector

    CERN Document Server

    Schorlemmer, André Lukas; Quadt, Arnulf; Große-Knetter, Jörn; Rembser, Christoph; Di Girolamo, Beniamino

    2014-11-05

    Radiation hardness is one of the most important features of the ATLAS pixel detector in order to ensure a good performance and a long lifetime. Monitoring of radiation damage is crucial in order to assess and predict the expected performance of the detector. Key values for the assessment of radiation damage in silicon, such as the depletion voltage and depletion depth in the sensors, are measured on a regular basis during operations. This thesis summarises the monitoring program that is conducted in order to assess the impact of radiation damage and compares it to model predictions. In addition, the physics performance of the ATLAS detector highly depends on the amount of disabled modules in the ATLAS pixel detector. A worrying amount of module failures was observed during run I. Thus it was decided to recover repairable modules during the long shutdown (LS1) by extracting the pixel detector. The impact of the module repairs and module failures on the detector performance is analysed in this thesis.

  8. Prader-Willi Syndrome and Schaaf-Yang Syndrome: Neurodevelopmental Diseases Intersecting at the MAGEL2 Gene

    Directory of Open Access Journals (Sweden)

    Michael D. Fountain

    2016-01-01

    Full Text Available Prader-Willi syndrome (PWS is a neurodevelopmental disorder characterized by neonatal hypotonia, developmental delay/intellectual disability, and characteristic feeding behaviors with failure to thrive during infancy; followed by hyperphagia and excessive weight gain later in childhood. Individuals with PWS also manifest complex behavioral phenotypes. Approximately 25% meet criteria for autism spectrum disorder (ASD. PWS is caused by the absence of paternally expressed, maternally silenced genes at chromosome 15q11-q13. MAGEL2 is one of five protein-coding genes in the PWS-critical domain. Truncating point mutations of the paternal allele of MAGEL2 cause Schaaf-Yang syndrome, which has significant phenotypic overlap with PWS, but is also clinically distinct; based on the presence of joint contractures, and a particularly high prevalence of autism spectrum disorder (up to 75% of affected individuals. The clinical and molecular overlap between PWS and Schaaf-Yang syndrome, but also their distinguishing features provide insight into the pathogenetic mechanisms underlying both disorders.

  9. This detector can't be built (without lots of work)

    CERN Document Server

    Breidenbach, M

    2002-01-01

    Most of us believe that e sup + e sup - detectors are technically trivial compared to those for hadron colliders and that detectors for linear colliders are extraordinarily trivial. The cross sections are tiny; there are approximately no radiation issues (compared to real machines) and for linear colliders, the situation is even simpler. The crossing rate is miniscule, so that hardware triggers are not needed, the DAQ is very simple, and the data processing requirements are quite modest. The challenges arise from the emphasis on precision measurements within reasonable cost constraints. The Silicon Detector, SD, is a ''preconceptual'' design of a high performance detector for the NLC, with reasonably uncompromised performance in general and stressing superb energy flow performance with its electromagnetic calorimeter (ECal). However, it is assumed from the beginning that funding will be very tight and that the detector costs must be constrained and rational. It also remains to be demonstrated by detailed simu...

  10. Measurement of ionising radiation semiconductor detectors: a review

    International Nuclear Information System (INIS)

    Aussel, J.P.

    1986-06-01

    Manufacturing techniques for nuclear detectors using semiconductors are constantly advancing, and a large range of models with different specificities and characteristics are available. After a theoretical reminder, this report describes the main types of detectors, their working and their preferential use. A comparative table guides the neophyte reader in his choice [fr

  11. 2011 ATLAS Detector Performance - ID and Forward detectors

    CERN Document Server

    Davies‎, E; The ATLAS collaboration; Abdel Khalek, S

    2012-01-01

    This poster describes the performance of 2 parts of ATLAS: - The Inner Detector which consists of 3 subdetectors: the Pixel detector, the SemiConductor Tracker (or SCT) and the Transition Radiation Tracker (or TRT). Here, we report on Pixel detector and SCT performance over 2011. - ALFA detector which will determine the absolute luminosity of the CERN LHC at the ATLAS Interaction Point (IP), and the total proton-proton cross section, by tracking elastically scattered protons at very small angles in the limit of the Coulomb Nuclear interference region.

  12. Infrared detectors

    CERN Document Server

    Rogalski, Antonio

    2010-01-01

    This second edition is fully revised and reorganized, with new chapters concerning third generation and quantum dot detectors, THz detectors, cantilever and antenna coupled detectors, and information on radiometry and IR optics materials. Part IV concerning focal plane arrays is significantly expanded. This book, resembling an encyclopedia of IR detectors, is well illustrated and contains many original references … a really comprehensive book.-F. Sizov, Institute of Semiconductor Physics, National Academy of Sciences, Kiev, Ukraine

  13. High unacylated ghrelin levels support the concept of anorexia in infants with prader-willi syndrome.

    Science.gov (United States)

    Beauloye, Veronique; Diene, Gwenaelle; Kuppens, Renske; Zech, Francis; Winandy, Coralie; Molinas, Catherine; Faye, Sandy; Kieffer, Isabelle; Beckers, Dominique; Nergårdh, Ricard; Hauffa, Berthold; Derycke, Christine; Delhanty, Patrick; Hokken-Koelega, Anita; Tauber, Maithé

    2016-05-04

    Prader-Willi syndrome (PWS) is a rare genetic neurodevelopmental disorder with different nutritional phases from suckling deficit with failure to thrive to early onset of obesity. Hyperghrelinemia has been described in PWS long before the development of obesity. Ghrelin is found in both acylated (AG) and unacylated (UAG) forms in the circulation. In contrast to AG, UAG has been shown to inhibit food intake and to be elevated in anorexia nervosa. The present project is aiming to determine the underlying mechanisms driving the different nutritional phases in PWS. Measurement of at least 4 h-fasting plasma acylated and unacylated ghrelin in 37 infants with a genetic diagnosis of PWS aged from 1 month to 4 years and in 100 age-matched controls without endocrine disorder recruited prior to minor surgery. One blood sampling was analysed for each patient/control and clinical data were recorded. Eleven PWS infants underwent repetitive blood samples at 3 or 6-month intervals during routine visits. In infants with PWS, AG is not elevated (p = 0.45), UAG is significantly higher (p = 0.0044; confidence interval 1.06;1.33) resulting in a low AG/UAG ratio (p = 0.0056; confidence interval 0.76;0.95) compared to controls. Unlike children and adults with PWS that have high AG and AG/UAG ratio, infants with PWS have elevated UAG that supports the concept of anorexia in the early phases of the disease. The change in AG/UAG ratio possibly drives the switch from failure to thrive to obesity. NCT02529085 .

  14. Evaluation of the detector response function digital conventional radiology

    International Nuclear Information System (INIS)

    Arino Gil, A.; Hernandez Rodriguez, J.; Mateos Salvador, P.; Rodriguez Lopez, B.; Font Gelabert, J. C.

    2013-01-01

    The objective of this work is to obtain the response function that relates the air kerma at the entrance of the detector and pixel value, for a series of digital detectors of conventional Radiology model Optimus DigitalDiagnost Philips () and 6000 Definium General Electric. From the set of measurements is obtained a response function for each reference type of detector, and compared with those published in the literature for these teams. (Author)

  15. Study of semiconductor detectors applied to diagnostic X-ray

    International Nuclear Information System (INIS)

    Salgado, Cesar Marques

    2003-08-01

    This work aims an evaluation of procedures for photons spectrum determination, produced by a X ray tube, normally used for medical diagnoses which operation voltage ranges from 20 to 150 kVp, to allow more precise characterization of the photon beam. The use of spectrum analysis will contribute to reduce the uncertainty in the ionization camera calibrations. For this purpose, two kind of detectors were selected, a Cadmium Zinc Telluride (CZT) and a planar HPGe detector. The X ray interaction with the detector's crystal produces, by electronic processes, a pulse high distribution as an output, which is no the true photon spectrum, due to the presence of K shell escape peaks, Compton scattering and to the fact that the detectors efficiency diminish rapidly with the increase of the photon energy. A detailed analysis of the contributing factors to distortions in the spectrum is necessary and was performed by Monte Carlo calculation with the MCNP 4B computer code. In order to determine the actual photon spectrum for a X ray tube a spectra stripping procedure is described for the HPGe detector. The detector's response curves, determined by the Monte Carlo calculation, were compared to the experimental ones, for isotropic point sources. For the methodology validation, stripped spectra were compared to the theoretical ones, for the same X ray tube's settings, for a qualitative evaluation. The air kerma rate calculated with the photon spectra were compared to the direct measurement using an ionization chamber, for a quantitative evaluation. (author)

  16. Radiation damage study in CZT matrix detectors exposed to gamma rays

    International Nuclear Information System (INIS)

    Leyva Fabelo, Antonio; Pinnera Hernandez, Ibrahin; Cruz Inclan, Carlos Manuel; Abreu Alfonso, Yamiel; Dona Lemus, Olga; Diaz Garcia, Angelina; Montanno Zetina, Luis Manuel

    2009-01-01

    Radiation damage in terms of atomic displacements in a typical CZT detector used in medical imaging applications was studied using the Monte Carlo statistical method. All detector structural and geometric features as well as different energies of the photons usually used in the application were taken into account. Considering the Mott McKinley Feshbach classical approach, effective cross sections of the displacements were calculated, including the number of displacements per atom for each atomic species present in the material and each photon energy considered. These results are analyzed and compared. Finally, the radiation damage on CZT detector is compared to that calculated in a similar detector manufactured with other semiconducting materials. (author)

  17. Performance comparison of scintillators for alpha particle detectors

    Energy Technology Data Exchange (ETDEWEB)

    Morishita, Yuki [Graduate School of Medicine, Nagoya University, 1-1-20 Daiko-Minami, Higashi-ku, Nagoya, Aichi 461-8673 (Japan); Japan Atomic Energy Agency, Muramatsu 4-33, Tokai-mura, Ibaraki 319-1194 (Japan); Yamamoto, Seiichi [Graduate School of Medicine, Nagoya University, 1-1-20 Daiko-Minami, Higashi-ku, Nagoya, Aichi 461-8673 (Japan); Izaki, Kenji [Japan Atomic Energy Agency, Muramatsu 4-33, Tokai-mura, Ibaraki 319-1194 (Japan); Kaneko, Junichi H.; Toui, Kohei; Tsubota, Youichi; Higuchi, Mikio [Graduate School of Engineering, Hokkaido University, Kita 13, Nishi 8, Kita-ku, Sapporo, Hokkaido 060-8628 (Japan)

    2014-11-11

    Scintillation detectors for alpha particles are often used in nuclear fuel facilities. Alpha particle detectors have also become important in the research field of radionuclide therapy using alpha emitters. ZnS(Ag) is the most often used scintillator for alpha particle detectors because its light output is high. However, the energy resolution of ZnS(Ag)-based scintillation detectors is poor because they are not transparent. A new ceramic sample, namely the cerium doped Gd{sub 2}Si{sub 2}O{sub 7} (GPS) scintillator, has been tested as alpha particle detector and its performances have been compared to that one of three different scintillating materials: ZnS(Ag), GAGG and a standard plastic scintillator. The different scintillating materials have been coupled to two different photodetectors, namely a photomultiplier tube (PMT) and a Silicon Photo-multiplier (Si-PM): the performances of each detection system have been compared. Promising results as far as the energy resolution performances (10% with PMT and 14% with Si-PM) have been obtained in the case of GPS and GAGG samples. Considering the quantum efficiencies of the photodetectors under test and their relation to the emission wavelength of the different scintillators, the best results were achieved coupling the GPS with the PMT and the GAGG with the Si-PM.

  18. Fabrication of radiation detector using PbI2 crystals

    International Nuclear Information System (INIS)

    Shoji, T.; Ohba, K.; Suehiro, T.; Hiratate, Y.

    1995-01-01

    Radiation detectors have been fabricated from lead iodide (PbI 2 ) crystals grown by two methods: zone melting and Bridgman methods. In response characteristics of the detector fabricated from crystals grown by the zone melting method, a photopeak for γ-rays from an 241 Am source (59.5 KeV) has been clearly observed with applied detector bias of 500 V at room temperature. The hole drift mobility is estimated to be about 5.5 cm 2 /Vs from measurement of pulse rise time for 5.48 MeV α-rays from 241 Am. By comparing the detector bias versus saturated peak position of the PbI 2 detector with that of CdTe detector, the average energy for producing electron-hole pairs is estimated to be about 8.4 eV for the PbI 2 crystal. A radiation detector fabricated from PbI 2 crystals grown by the Bridgman method, however, exhibited no response for γ-rays

  19. Polymer fiber detectors for photoacoustic imaging

    Science.gov (United States)

    Grün, Hubert; Berer, Thomas; Pühringer, Karoline; Nuster, Robert; Paltauf, Günther; Burgholzer, Peter

    2010-02-01

    Photoacoustic imaging is a novel imaging method for medical and biological applications, combining the advantages of Diffuse Optical Imaging (high contrast) and Ultrasonic Imaging (high spatial resolution). A short laser pulse hits the sample. The absorbed energy causes a thermoelastic expansion and thereby launches a broadband ultrasonic wave (photoacoustic signal). The distribution of absorbed energy density is reconstructed from measurements of the photoacoustic signals around the sample. For collecting photoacoustic signals either point like or extended, integrating detectors can be used. The latter integrate the pressure at least in one dimension, e.g. along a line. Thereby, the three dimensional imaging problem is reduced to a two dimensional problem. For a tomography device consisting of a scanning line detector and a rotating sample, fiber-based detectors made of polymer have been recently introduced. Fiber-based detectors are easy to use and possess a constant, high spatial resolution over their entire active length. Polymer fibers provide a better impedance matching and a better handling compared with glass fibers which were our first approach. First measurement results using polymer fiber detectors and some approaches for improving the performance are presented.

  20. Silicon Drift Detectors - A Novel Technology for Vertex Detectors

    Science.gov (United States)

    Lynn, D.

    1996-10-01

    Silicon Drift Detectors (SDD) are novel position sensing silicon detectors which operate in a manner analogous to gas drift detectors. Single SDD's were shown in the CERN NA45 experiment to permit excellent spatial resolution (pseudo-rapidity. Over the last three years we undertook a concentrated R+D effort to optimize the performance of the detector by minimizing the inactive area, the operating voltage and the data volume. We will present test results from several wafer prototypes. The charge produced by the passage of ionizing particles through the bulk of the detectors is collected on segmented anodes, with a pitch of 250 μm, on the far edges of the detector. The anodes are wire-bonded to a thick film multi-chip module which contains preamplifier/shaper chips and CMOS based switched capacitor arrays used as an analog memory pipeline. The ADC is located off-detector. The complete readout chain from the wafer to the DAQ will be presented. Finally we will show physics performance simulations based on the resolution achieved by the SVT prototypes.

  1. Copy Protection in Jet Set Willy: developing methodology for retrogame archaeology

    Directory of Open Access Journals (Sweden)

    John Aycock

    2017-04-01

    Full Text Available Video games, and more generally computer games, are unquestionably technological artefacts that have cultural significance. Old computer games in particular had to function under technical constraints that would be alien to many modern programmers, while at the same time providing something novel and at first foreign to consumers. How did their creators accomplish their technical feats, and what impact did that have for the player-consumer? The study of 'retro' computer games' implementation is one topic within the nascent area of archaeogaming. Digital rights management (DRM continues to be a major issue in the protection and distribution of content in electronic form. In this article, we study an early example of the implementation of copy protection in the 1984 game Jet Set Willy, something that comprises both physical and digital artefacts. It acts as a vehicle to illustrate a number of methods that we used to understand game implementation, culminating in a full reconstruction of the technique. The methods we cover include: 'traditional' research, along with its limitations in this context; code and data analysis; hypothesis testing; reconstruction. Through this positivist experimental approach, our results are both independently verifiable and repeatable. We also approach the complex context of early DRM, its hacks and workarounds by the player community, and what precipitated the design choices made for this particular game.

  2. Highly restricted deletion of the SNORD116 region is implicated in Prader–Willi Syndrome

    Science.gov (United States)

    Bieth, Eric; Eddiry, Sanaa; Gaston, Véronique; Lorenzini, Françoise; Buffet, Alexandre; Conte Auriol, Françoise; Molinas, Catherine; Cailley, Dorothée; Rooryck, Caroline; Arveiler, Benoit; Cavaillé, Jérome; Salles, Jean Pierre; Tauber, Maïthé

    2015-01-01

    The SNORD116 locus lies in the 15q11-13 region of paternally expressed genes implicated in Prader–Willi Syndrome (PWS), a complex disease accompanied by obesity and severe neurobehavioural disturbances. Cases of PWS patients with a deletion encompassing the SNORD116 gene cluster, but preserving the expression of flanking genes, have been described. We report a 23-year-old woman who presented clinical criteria of PWS, including the behavioural and nutritional features, obesity, developmental delay and endocrine dysfunctions with hyperghrelinemia. We found a paternally transmitted highly restricted deletion of the SNORD116 gene cluster, the shortest described to date (118 kb). This deletion was also present in the father. This finding in a human case strongly supports the current hypothesis that lack of the paternal SNORD116 gene cluster has a determinant role in the pathogenesis of PWS. Moreover, targeted analysis of the SNORD116 gene cluster, complementary to SNRPN methylation analysis, should be carried out in subjects with a phenotype suggestive of PWS. PMID:24916642

  3. Management of disused smoke detectors

    International Nuclear Information System (INIS)

    Lacroix, J.P.

    2001-01-01

    Full text: Smoke detectors containing radioisotopes with long half-life (such as 241 Am and 239 Pu), are widely used all over the world. Very small activities are required for this application but in each country, the smoke detectors are present by thousands. The volume of the radioactive sources being so small compared to the overall volume of the device, the volume reduction is the only responsible option for their management and storage. These sources, collected as such, require deep geological repository that so far are not operational anywhere. The conditioning and the packaging should try to meet the requirement for future repository. The National Institute for Radioelements, in Belgium, (IRE) has acquired a wide experience in the field of handling, conditioning and storage of disused smoke detectors and lightning preventers mainly based on 241 Am sources. Up to now, more than forty different types of smoke detectors were dismantled in the IRE facilities representing a total amount of more than 30,000 items. This report presents a practical management option for disused smoke detectors sources and provides an example of specific technical procedure for 241 Am sources handling and conditioning for long term storage. This management option does not request heavy infrastructure. For this reason this practical approach can be implemented in every waste treatment facility including those in the developing countries. (author)

  4. An improved multicrystal 2-D BGO detector for PET

    International Nuclear Information System (INIS)

    Rogers, J.G.; Taylor, A.J.; Rahimi, M.F.; Nutt, R.; Andreaco, M.; Williams, C.W.

    1992-01-01

    In this paper, the authors evaluate and compare two new 2-D array detectors for PET. Both consist of an 8 x 8 array of small BGO crystals coupled to a 2 x 2 array of photomultiplier tubes. The depth of the crystals is 3 cm in one detector and 2 cm in the other. The 2 cm detector is obviously superior in terms of material costs, but is also superior in energy resolution per crystal, and in its ability to clearly identify the crystal containing the primary interaction. The authors present a flexible and robust algorithm for crystal identification in such array detectors. The prospect of obtaining still better spatial resolution from such block detectors, with increased numbers of crystals, is discussed

  5. The use of medical care and the prevalence of serious illness in an adult Prader-Willi syndrome cohort.

    Science.gov (United States)

    Sinnema, Margje; Maaskant, Marian A; van Schrojenstein Lantman-de Valk, Henny M J; Boer, Harm; Curfs, Leopold M G; Schrander-Stumpel, Constance T R M

    2013-08-01

    Adults with Prader-Willi syndrome (PWS) have an increased occurrence of several medical conditions. We report on the consequences of high morbidity rates such as prevalence rate of hospital admissions, medication use and surgery in a Dutch cohort of adults with PWS. Special attention is paid to causes and symptoms of serious illness. Participants were contacted via the Dutch Prader-Willi Parent Association and through physicians specializing in persons with ID. The persons with PWS and their main caregivers were visited at home. Information was collected through semi-structured interviews on 102 adults with PWS. The need for medical care in the neonatal period is associated with hypotonia and feeding problems. Hospital admissions for respiratory tract infections are frequent. During childhood most hospital admissions were due to PWS syndrome specific surgery. During adolescence hospital admissions occurred for scoliosis surgery and endocrine evaluations. At adult age, hospitalization was associated with inguinal hernia surgery, diabetes mellitus, psychosis, erysipelas, water and drug intoxications. In the older group, respiratory infections were again the main reason for hospital admissions. Frequently used medications at adult age included psychotropics, laxatives, anti-diabetics and dermatologic preparations. Abnormal drinking patterns, problems with anesthesia, decreased ability to vomit, abnormal pain awareness and unpredictable fever responses were frequent and often lead to delayed diagnoses of serious conditions. People with PWS are frequent users of medical-care. Reasons for hospitalization and medication use are age specific. Knowledge on the different presentation of symptoms in people with PWS is needed. In case of unexplained illness, disturbances of consciousness and behavioral changes in people with PWS, an infection should be ruled out in the first place. Information from this study may help in preventing conditions and recognizing conditions in an

  6. Study of a scintillation neutron detector of 1OB+ZnS(Ag) as alternative to the 3He detectors: model MCNPX and validation

    International Nuclear Information System (INIS)

    Guzman G, K. A.; Gallego D, E.; Lorente F, A.; Ibanez F, S.; Vega C, H. R.; Mendez V, R.; Gonzalez, J. A.

    2015-10-01

    Using Monte Carlo methods with the code MCNPX, was estimated the response of a scintillation neutron detector of Zn S(Ag) with a mixture of 10 B high enrichment. The detector consists of four plates of Poly (methyl methacrylate) (PMMA) and five layers of ∼0, 017 cm 10 B+ZnS(Ag) in contact with PMMA. The naked detector response was calculated and with different thicknesses of high density polyethylene moderator, for 29 monoenergetic sources and for sources of 241 AmBe and 252 Cf of neutrons. In these calculations the reactions 10 B(n,α) 7 Li and neutron fluence in the sensitive area of detector 10 B+ZnS(Ag) were estimated. Measurements were performed in the Laboratory of Neutron Measurement to quantify detections in counts per second to a neutron source of 252 Cf to 200 cm on the bench, modeling with MCNPX, these measures were compared to validate the model and the Zn S(Ag) efficiency of α detection was estimated. Calculations in the LPN-CIEMAT were realized. Starting from the validation new models were carried out with geometries that improve the detector response, trying reaching the detection of 2, 5 cps-ng of 252 Cf comparable requirement for responding to the installed equipment of 3 He in the radiation portal monitor. This type of detector can be considered an alternative to detectors of 3 He for detecting special nuclear material. (Author)

  7. Spiral silicon drift detectors

    International Nuclear Information System (INIS)

    Rehak, P.; Gatti, E.; Longoni, A.; Sampietro, M.; Holl, P.; Lutz, G.; Kemmer, J.; Prechtel, U.; Ziemann, T.

    1988-01-01

    An advanced large area silicon photodiode (and x-ray detector), called Spiral Drift Detector, was designed, produced and tested. The Spiral Detector belongs to the family of silicon drift detectors and is an improvement of the well known Cylindrical Drift Detector. In both detectors, signal electrons created in silicon by fast charged particles or photons are drifting toward a practically point-like collection anode. The capacitance of the anode is therefore kept at the minimum (0.1pF). The concentric rings of the cylindrical detector are replaced by a continuous spiral in the new detector. The spiral geometry detector design leads to a decrease of the detector leakage current. In the spiral detector all electrons generated at the silicon-silicon oxide interface are collected on a guard sink rather than contributing to the detector leakage current. The decrease of the leakage current reduces the parallel noise of the detector. This decrease of the leakage current and the very small capacities of the detector anode with a capacitively matched preamplifier may improve the energy resolution of Spiral Drift Detectors operating at room temperature down to about 50 electrons rms. This resolution is in the range attainable at present only by cooled semiconductor detectors. 5 refs., 10 figs

  8. Systematic review of the clinical and genetic aspects of Prader-Willi syndrome

    Directory of Open Access Journals (Sweden)

    Dong Kyu Jin

    2011-02-01

    Full Text Available Prader-Willi syndrome (PWS is a complex multisystem genetic disorder that is caused by the lack of expression of paternally inherited imprinted genes on chromosome 15q11&#8211;q13. This syndrome has a characteristic phenotype including severe neonatal hypotonia, early-onset hyperphagia, development of morbid obesity, short stature, hypogonadism, learning disabilities, behavioral problems, and psychiatric problems. PWS is an example of a genetic condition caused by genomic imprinting. It can occur via 3 main mechanisms that lead to the absence of expression of paternally inherited genes in the 15q11.2&#8211;q13 region: paternal microdeletion, maternal uniparental disomy, and an imprinting defect. Over 99% of PWS cases can be diagnosed using DNA methylation analysis. Early diagnosis of PWS is important for effective long-term management. Growth hormone (GH treatment improves the growth, physical phenotype, and body composition of patients with PWS. In recent years, GH treatment in infants has been shown to have beneficial effects on the growth and neurological development of patients diagnosed during infancy. There is a clear need for an integrated multidisciplinary approach to facilitate early diagnosis and optimize management to improve quality of life, prevent complications, and prolong life expectancy in patients with PWS.

  9. Reduced cortical complexity in children with Prader-Willi Syndrome and its association with cognitive impairment and developmental delay.

    Science.gov (United States)

    Lukoshe, Akvile; Hokken-Koelega, Anita C; van der Lugt, Aad; White, Tonya

    2014-01-01

    Prader-Willi Syndrome (PWS) is a complex neurogenetic disorder with symptoms involving not only hypothalamic, but also a global, central nervous system dysfunction. Previously, qualitative studies reported polymicrogyria in adults with PWS. However, there have been no quantitative neuroimaging studies of cortical morphology in PWS and no studies to date in children with PWS. Thus, our aim was to investigate and quantify cortical complexity in children with PWS compared to healthy controls. In addition, we investigated differences between genetic subtypes of PWS and the relationship between cortical complexity and intelligence within the PWS group. High-resolution structural magnetic resonance images were acquired in 24 children with genetically confirmed PWS (12 carrying a deletion (DEL), 12 with maternal uniparental disomy (mUPD)) and 11 age- and sex-matched typically developing siblings as healthy controls. Local gyrification index (lGI) was obtained using the FreeSurfer software suite. Four large clusters, two in each hemisphere, comprising frontal, parietal and temporal lobes, had lower lGI in children with PWS, compared to healthy controls. Clusters with lower lGI also had significantly lower cortical surface area in children with PWS. No differences in cortical thickness of the clusters were found between the PWS and healthy controls. lGI correlated significantly with cortical surface area, but not with cortical thickness. Within the PWS group, lGI in both hemispheres correlated with Total IQ and Verbal IQ, but not with Performance IQ. Children with mUPD, compared to children with DEL, had two small clusters with lower lGI in the right hemisphere. lGI of these clusters correlated with cortical surface area, but not with cortical thickness or IQ. These results suggest that lower cortical complexity in children with PWS partially underlies cognitive impairment and developmental delay, probably due to alterations in gene networks that play a prominent role in

  10. Radiation detectors laboratory

    International Nuclear Information System (INIS)

    Ramirez J, F.J.

    1996-01-01

    The National Institute for Nuclear Research has established a Radiation detector laboratory that has the possibility of providing to the consultants on the handling and applications of the nuclear radiation detectors. It has special equipment to repair the radiation detectors used in spectroscopy as the hyper pure Germanium for gamma radiation and the Lithium-silica for X-rays. There are different facilities in the laboratory that can become useful for other institutions that use radiation detectors. This laboratory was created to satisfy consultant services, training and repairing of the radiation detectors both in national and regional levels for Latin America. The laboratory has the following sections: Nuclear Electronic Instrumentation; where there are all kind of instruments for the measurement and characterization of detectors like multichannel analyzers of pulse height, personal computers, amplifiers and nuclear pulse preamplifiers, nuclear pulses generator, aleatories, computer programs for radiation spectra analysis, etc. High vacuum; there is a vacuum escape measurer, two high vacuum pumps to restore the vacuum of detectors, so the corresponding measurers and the necessary tools. Detectors cleaning; there is an anaerobic chamber for the detectors handling at inert atmosphere, a smoke extraction bell for cleaning with the detector solvents. Cryogenic; there are vessels and tools for handling liquid nitrogen which is used for cooling the detectors when they required it. (Author)

  11. Electronic noise of superconducting tunnel junction detectors

    International Nuclear Information System (INIS)

    Jochum, J.; Kraus, H.; Gutsche, M.; Kemmather, B.; Feilitzsch, F. v.; Moessbauer, R.L.

    1994-01-01

    The optimal signal to noise ratio for detectors based on superconducting tunnel junctions is calculated and compared for the cases of a detector consisting of one single tunnel junction, as well as of series and of parallel connections of such tunnel junctions. The influence of 1 / f noise and its dependence on the dynamical resistance of tunnel junctions is discussed quantitatively. A single tunnel junction yields the minimum equivalent noise charge. Such a tunnel junction exhibits the best signal to noise ratio if the signal charge is independent of detector size. In case, signal charge increases with detector size, a parallel or a series connection of tunnel junctions would provide the optimum signal to noise ratio. The equivalent noise charge and the respective signal to noise ratio are deduced as functions of tunnel junction parameters such as tunneling time, quasiparticle lifetime, etc. (orig.)

  12. Temperature distribution model for the semiconductor dew point detector

    Science.gov (United States)

    Weremczuk, Jerzy; Gniazdowski, Z.; Jachowicz, Ryszard; Lysko, Jan M.

    2001-08-01

    The simulation results of temperature distribution in the new type silicon dew point detector are presented in this paper. Calculations were done with use of the SMACEF simulation program. Fabricated structures, apart from the impedance detector used to the dew point detection, contained the resistive four terminal thermometer and two heaters. Two detector structures, the first one located on the silicon membrane and the second one placed on the bulk materials were compared in this paper.

  13. nGEM fast neutron detectors for beam diagnostics

    International Nuclear Information System (INIS)

    Croci, G.; Claps, G.; Cavenago, M.; Dalla Palma, M.; Grosso, G.; Murtas, F.; Pasqualotto, R.; Perelli Cippo, E.; Pietropaolo, A.; Rebai, M.; Tardocchi, M.; Tollin, M.; Gorini, G.

    2013-01-01

    Fast neutron detectors with a sub-millimetric space resolution are required in order to qualify neutron beams in applications related to magnetically-controlled nuclear fusion plasmas and to spallation sources. A nGEM detector has been developed for the CNESM diagnostic system of the SPIDER NBI prototype for ITER and as beam monitor for fast neutrons lines at spallation sources. The nGEM is a triple GEM gaseous detector equipped with polypropylene and polyethylene layers used to convert fast neutrons into recoil protons through the elastic scattering process. This paper describes the results obtained by testing a nGEM detector at the ISIS spallation source on the VESUVIO beam line. Beam profiles (σ x =14.35 mm, σ y =15.75 mm), nGEM counting efficiency (around 10 -4 for 3 MeV n <15 MeV), detector stability (≈4.5%) and the effect of filtering the beam with different type of materials were successfully measured. The x beam profile was compared to the one measured by a single crystal diamond detector. Finally, the efficiency of the detector was simulated exploiting the GEANT4 tool

  14. Application of energy dispersive X-ray spectrometers with semiconductor detectors in radiometric analyses

    International Nuclear Information System (INIS)

    Jugelt, P.; Schieckel, M.

    1983-01-01

    Problems and possibilities of applying semiconductor detector spectrometers in radiometric analyses are described. A summary of the state of the art and tendencies of device engineering and spectra evaluation is given. Liquid-nitrogen cooled Li-drifted Si-detectors and high-purity Ge-detectors are compared. Semiconductor detectors working at room temperature are under development. In this connection CdTe and HgI 2 semiconductor detectors are compared. The use of small efficient computers in the spectrometer systems stimulates the development of algorithms for spectra analyses and for determining the concentration. Fields of application of energy dispersive X-ray spectrometers are X-ray diffraction and X-ray macroanalysis in investigating the structure of extensive surface regions

  15. On the suitability of P Si-PIN detectors in transmission experiments

    International Nuclear Information System (INIS)

    Murty, V.R.K.; Devan, K.R.S.

    2000-01-01

    There has been considerable interest, in the recent past, in the development of detector technology. In this context, new detectors, especially room temperature operated detectors and inexpensive cooling systems have recently entered the market. These new systems replace the old systems where there are inadequate facilities to operate them to achieve superior performance. Such performance capabilities of different systems, on a comparative basis have not been widely published in the recent past. In this direction, the Peltier cooled detectors have entered the market and are replacing the conventional Si(Li) detectors. In between the conventional Si(Li) detectors and Peltier cooled Si-PIN detectors, the freolectric cooled Si(Li) detectors were also used in Radiation Physics applications. In this paper, the performance of the Peltier cooled Si-PIN detector in comparison with a Freolectric cooled Si(Li) detector has been studied in Transmission experiments to evaluate the total cross sections at low energies and the results are discussed. (author)

  16. A systematic study of BNL's 3D-Trench Electrode detectors

    International Nuclear Information System (INIS)

    Montalbano, A.; Bassignana, D.; Li, Z.; Liu, S.; Lynn, D.; Pellegrini, G.; Tsybychev, D.

    2014-01-01

    New types of silicon pixel detectors have been proposed because of the need for more radiation hard semiconductor devices for the high luminosity tracking detector upgrades at the Large Hadron Collider. A novel type of 3D Si pixel detectors is proposed, with each cell of the 3D-Trench Electrode pixel detector featuring a concentric trench electrode surrounding the central collecting column electrode. The pixel sensor is an array of those individual cells. Systematic 3D simulations using Silvacos TCAD programs have been carried out to study the characteristics of this novel 3D pixel design and to compare to the traditional 3D column electrode pixel design. The 3D simulations show a much lower depletion voltage and a more uniform electric field in the new 3D-Trench Electrode pixel detectors as compared to the traditional 3D column Electrode detectors. The first prototype 3D-Trench Electrode pixel detectors have been manufactured at the Centro Nacional De Microelectronica. Preliminary electrical measurements are discussed and charge collection efficiency measurements are presented

  17. Radiometric and dosimetric characteristics of HgI2 detectors

    International Nuclear Information System (INIS)

    Zaletin, V.M.; Krivozubov, O.V.; Torlin, M.A.; Fomin, V.I.

    1988-01-01

    The characteristics of HgI 2 detectors in x-ray and gamma detection in applications to radiometric and dosimetric monitoring and as portable instruments for such purposes was considered. Blocks with mosaic and sandwich structures were prepared and tested against each other and, for comparative purposes, against CdTe detectors for relative sensitivities at various gamma-quanta energies. Sensitivity dependencies on gamma radiation energy were plotted for the detector materials and structures as were current dependencies on the dose rate of x rays. Results indicated that the mercury iodide detectors could be used in radiometric and dosimetric measurements at gamma quantum energies up to and in excess of 1000 KeV

  18. Mercuric iodide semiconductor detectors encapsulated in polymeric resin

    Energy Technology Data Exchange (ETDEWEB)

    Martins, Joao F. Trencher; Santos, Robinson A. dos; Ferraz, Caue de M.; Oliveira, Adriano S.; Velo, Alexandre F.; Mesquita, Carlos H. de; Hamada, Margarida M., E-mail: mmhamada@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Disch, Christian; Fiederle, Michael [Albert-Ludwigs Universität Freiburg - UniFreibrug, Freiburg Materials Research Center - FMF, Freiburg (Germany)

    2015-07-01

    The development of new semiconductor radiation detectors always finds many setback factors, such as: high concentration of impurities in the start materials, poor long term stability, the surface oxidation and other difficulties discussed extensively in the literature, that limit their use. In this work was studied, the application of a coating resin on HgI2 detectors, in order to protect the semiconductor crystal reactions from atmospheric gases and to isolate electrically the surface of the crystals. Four polymeric resins were analyzed: Resin 1: 50% - 100%Heptane, 10% - 25% methylcyclohexane, <1% cyclohexane; Resin 2: 25% - 50% ethanol, 25% - 50% acetone, <2,5% ethylacetate; Resin 3: 50% - 100% methylacetate, 5% - 10% n-butylacetate; Resin 4: 50% - 100% ethyl-2-cyanacrylat. The influence of the polymeric resin type used on the spectroscopic performance of the HgI{sub 2} semiconductor detector is, clearly, demonstrated. The better result was found for the detector encapsulated with Resin 3. An increase of up to 26 times at the stability time was observed for the detectors encapsulated compared to that non-encapsulated detector. (author)

  19. 20 years of cosmic muons research performed in IFIN-HH

    International Nuclear Information System (INIS)

    Mitrica, Bogdan

    2012-01-01

    During the last two decades a modern direction in particle physics research has been developed in IFIN-HH Bucharest, Romania. The history started with the WILLI detector built in IFIN-HH Bucharest in collaboration with KIT Karlsruhe (formerly Forschungszentrum Karlsruhe). The detector was designed for measurements of the low energy muon charge ratio ( 0.4GeV, show a diurnal modulation of the muon flux. The analysis of the muon events for energies 15 eV. Simulation studies and preliminary experimental tests, regarding the performances of the mini-array, have been performed using H and Fe primaries, with energies in a range 10 13 eV - 10 15 eV. The results show detailed effects of the direction of EAS incidence relative to the geomagnetic field, depending, in particular, of the primary mass. Based on the results, we can say that WILLI-EAS experiment could be used for testing the hadronic interaction models. Measurements of the high energy muon flux in underground of the salt mine from Slanic Prahova, Romania was performed using a new mobile detector developed in IFIN-HH, Bucharest. Consisting of 2 scintillator plates measuring in coincidence, the detector is installed on a van which facilitates measurements on different positions at surface or in underground. The detector was used to measure muon fluxes in different locations at surface or in underground. The detector was used to measure muon fluxes at different sites of Romania and in the underground of the salt mines from Slanic Prahova, Romania where IFIN-HH has a modern underground laboratory. New methods for the detection of cosmic ray muons are investigated in our institute based on scintillator techniques using optical fiber and MPPC photodyodes.

  20. Neutrino mass hierarchy determination via atmospheric neutrinos with future detectors

    International Nuclear Information System (INIS)

    Gandhi, Raj; Ghoshal, Pomita; Goswami, Srubabati; Mehta, Poonam; Sankar, S Uma; Shalgar, Shashank

    2008-01-01

    The issue of determining the neutrino mass hierarchy is one of the outstanding questions in neutrino physics. We consider the potential of hierarchy determination using atmospheric neutrinos as the source in three different proposed future detectors: A large Iron Calorimeter detector, a megaton Water Cerenkov detector and a large-mass Liquid Argon detector. If the mixing angle θ 13 is about 10 deg. (close to CHOOZ upper bound), the hierarchy sensitivity is essentially determined by resonant matter effects. To maximize the potential of these effects in atmospheric neutrinos, charge discrimination capability in the detector is desirable. Hence, detectors with this capability have an advantage in hierarchy determination. We compare and contrast the performance of the above three detectors in this respect. We perform a realistic analysis of the above future detectors for atmospheric neutrinos and show that it is possible to achieve a significant hierarchy sensitivity if the detector characteristics are favourable. Note: The abstract has been modified from its original form to incorporate suggestions received during the conference. The poster is being submitted in its original form.

  1. Noninvasive xenon-133 measurements of cerebral blood flow using stationary detectors compared with dynamic emission tomography

    DEFF Research Database (Denmark)

    Schroeder, T; Vorstrup, S; Lassen, N A

    1986-01-01

    the stationary detectors yielded somewhat lower CBF values than did emission tomography. Considering the side-to-side asymmetry, an excellent correlation was obtained. Using the initial slope index, the stationary detectors revealed quantitatively 83% of the interhemispheric asymmetry and 63% of the asymmetry...... in the middle cerebral artery territory shown with the tomograph. As illustrated by a case history, the nontomographic CBF unit used in this study may provide reliable and useful information in patients with occlusive cerebrovascular disease by performing repeated CBF studies and challenging the cerebral...

  2. Position sensitivity of the proposed segmented germanium detectors for the DESPEC project

    International Nuclear Information System (INIS)

    Khaplanov, A.; Tashenov, S.; Cederwall, B.

    2009-01-01

    The DESPEC HPGe array is a part of the NuSTAR project at FAIR, Germany. It is aimed at the spectroscopy of the stopped decaying exotic nuclei. Segmented γ-ray tracking detectors are proposed for this array in order to maximize detection efficiency and background suppression when searching for very rare events. Two types of detector modules-stacks of three 16-fold segmented planar crystals and 12- and 16-fold segmented clover detectors-have been investigated and compared from the point of view of the achievable position resolution using pulse shape analysis (PSA). To this end, detector signals from realistic γ-ray interactions have been calculated. These signals were treated by PSA in order to reconstruct the photon interaction locations. Comparing the initial interaction locations to the reconstructed ones, it was found that the double-sided strip planar detector yielded position reconstruction errors at least a factor 2 lower than the other detectors considered.

  3. Micro-channel cooling for silicon detectors

    Energy Technology Data Exchange (ETDEWEB)

    Flaschel, Nils

    2017-12-15

    Silicon tracking detectors employed in high-energy physics are located very close to the interaction points of the colliding particle beams. The high energetic radiation emerging from the interaction induces defects into the silicon, downgrading the efficiency to collect the charges created by passing particles and increasing the noise while data taking. Cooling the sensors to low temperatures can help to prevent defects and maintain a high efficiency and lower noise level. In order to maximize the LHC's discovery potential, the collider and its detectors will be upgraded to a higher luminosity around 2024. The conditions inside the detector will become harsher demanding that the technology must adapt to the new situation. Radiation damage is already an issue in the current ATLAS detector and therefore a huge number of parameters are constantly monitored and evaluated to ensure optimal operation. To provide the best possible settings the behavior of the sensors inside the ATLAS Inner Detector is predicted using simulations. In this work several parameters in the simulation including the depletion voltage and the crosstalk between sensor strips of the SCT detector are analyzed and compared with data. The main part of this work concerns the investigation of a novel cooling system based on microchannels etched into silicon in a generic research and development project at DESY and IMB-CNM. A channel layout is designed providing a homogeneous flow distribution across a large surface area and tested in a computational fluid simulation before its production. Two different fabrication techniques, anodic and eutectic bonding, are used to test prototypes with differing mechanical and thermal properties. Hydromechanical and thermal measurements are performed to fully characterize the flow inside the device and the thermal properties of the prototype in air and in a vacuum. The thermal behavior is analyzed by means of local measurements with thermal resistors and infrared

  4. Micro-channel cooling for silicon detectors

    International Nuclear Information System (INIS)

    Flaschel, Nils

    2017-12-01

    Silicon tracking detectors employed in high-energy physics are located very close to the interaction points of the colliding particle beams. The high energetic radiation emerging from the interaction induces defects into the silicon, downgrading the efficiency to collect the charges created by passing particles and increasing the noise while data taking. Cooling the sensors to low temperatures can help to prevent defects and maintain a high efficiency and lower noise level. In order to maximize the LHC's discovery potential, the collider and its detectors will be upgraded to a higher luminosity around 2024. The conditions inside the detector will become harsher demanding that the technology must adapt to the new situation. Radiation damage is already an issue in the current ATLAS detector and therefore a huge number of parameters are constantly monitored and evaluated to ensure optimal operation. To provide the best possible settings the behavior of the sensors inside the ATLAS Inner Detector is predicted using simulations. In this work several parameters in the simulation including the depletion voltage and the crosstalk between sensor strips of the SCT detector are analyzed and compared with data. The main part of this work concerns the investigation of a novel cooling system based on microchannels etched into silicon in a generic research and development project at DESY and IMB-CNM. A channel layout is designed providing a homogeneous flow distribution across a large surface area and tested in a computational fluid simulation before its production. Two different fabrication techniques, anodic and eutectic bonding, are used to test prototypes with differing mechanical and thermal properties. Hydromechanical and thermal measurements are performed to fully characterize the flow inside the device and the thermal properties of the prototype in air and in a vacuum. The thermal behavior is analyzed by means of local measurements with thermal resistors and infrared

  5. The GRANDE detector

    International Nuclear Information System (INIS)

    Adams, A.; Bond, R.; Coleman, L.; Rollefson, A.; Wold, D.; Bratton, C.B.; Gurr, H.; Kropp, W.; Nelson, M.; Price, L.R.; Reines, F.; Schultz, J.; Sobel, H.; Svoboda, R.; Yodh, G.; Burnett, T.; Chaloupka, V.; Wilkes, R.J.; Cherry, M.; Ellison, S.B.; Guzik, T.G.; Wefel, J.; Gaidos, J.; Loeffler, F.; Sembroski, G.; Wilson, C.; Goodman, J.; Haines, T.J.; Kielczewska, D.; Lane, C.; Steinberg, R.; Lieber, M.; Nagle, D.; Potter, M.; Tripp, R.

    1990-01-01

    In this paper we present a detector facility which meets the requirements outlined above for a next-generation instrument. GRANDE (Gamma Ray and Neutrino DEtector) is an imaging, water Cerenkov detector, which combines in one facility an extensive air shower array and a high-energy neutrino detector. (orig.)

  6. CVD polycrystalline diamond. A novel neutron detector and applications

    International Nuclear Information System (INIS)

    Mongkolnavin, R.

    1998-01-01

    Chemical Vapour Deposition (CVD) Polycrystalline Diamond film has been investigated as a low noise sensor for beta particles, gammas and neutrons using High Energy Physics technologies. Its advantages and disadvantages have been explored in comparison with other particle detectors such as silicon detector and other plastic scintillators. The performance and characteristic of the diamond detector have been fully studied and discussed. These studies will lead to a better understanding of how CVD diamonds perform as a detector and how to improve their performance under various conditions. A CVD diamond detector model has been proposed which is an attempt to explain the behaviour of such an extreme detector material. A novel neutron detector is introduced as a result of these studies. A good thermal and fast neutron detector can be fabricated with CVD diamond with new topologies. This detector will perform well without degradation in a high neutron radiation environment, as diamond is known to be radiation hard. It also offers better neutrons and gammas discrimination for high gamma background applications compared to other semiconductor detectors. A full simulation of the detector has also been done using GEANT, a Monte-Carlo simulation program for particle detectors. Simulation results show that CVD diamond detectors with this novel topology can detect neutrons with great directionality. Experimental work has been done on this detector in a nuclear reactor environment and accelerator source. A novel neutron source which offers a fast pulse high-energy neutrons has also been studied. With this detector, applications in neutron spectrometer for low-Z material have been pursued with various neutron detection techniques. One of these is a low-Z material identification system. The system has been designed and simulated for contraband luggage interrogation using the detector and the novel neutron source. Also other neutron related applications have been suggested. (author)

  7. CVD polycrystalline diamond. A novel neutron detector and applications

    International Nuclear Information System (INIS)

    Mongkolnavin, R.

    1998-07-01

    Chemical Vapour Deposition (CVD) Polycrystalline Diamond film has been investigated as a low noise sensor for beta particles, gammas and neutrons using High Energy Physics technologies. Its advantages and disadvantages have been explored in comparison with other particle detectors such as silicon detector and other plastic scintillators. The performance and characteristic of the diamond detector have been fully studied and discussed. These studies will lead to a better understanding of how CVD diamonds perform as a detector and how to improve their performance under various conditions. A CVD diamond detector model has been proposed which is an attempt to explain the behaviour of such an extreme detector material. A novel neutron detector is introduced as a result of these studies. A good thermal and fast neutron detector can be fabricated with CVD diamond with new topologies. This detector will perform well without degradation in a high neutron radiation environment, as diamond is known to be radiation-hard. It also offers better neutrons and gammas discrimination for high gamma background applications compared to other semiconductor detectors. A full simulation of the detector has also been done using GEANT, a Monte Carlo simulation program for particle detectors. Simulation results show that CVD diamond detectors with this novel topology can detect neutrons with great directionality. Experimental work has been done on this detector in a nuclear reactor environment and accelerator source. A novel neutron source which offers a fast pulse high-energy neutrons has also been studied. With this detector, applications in neutron spectrometry for low-Z material have been pursued with various neutron detection techniques. One of these is a low-Z material identification system. The system has been designed and simulated for contraband luggage interrogation using the detector and the novel neutron source. (author)

  8. Collateral Circles in Carotid Artery Occlusion. A Comparative Study between CW Doppler and contrast angiography

    Energy Technology Data Exchange (ETDEWEB)

    Giraldi, C; Marconi, F; Parenti, G; Lenzi, B; Canapicchi, R; Padolecchia, R

    1986-01-01

    In order to evaluate the presence and efficacy of the different collateral circles, 98 patients with occlusion of the internal carotid artery between its origin and the origin of the ophtalmic artery, has been examined. Before contrast angiography, each patients was submitted to a Doppler examination with test of compression on the exsternal and common carotid arteries. The information on the collateral circles (Willis and pre-Willis) deriving from the Doppler examination seems to be interesting and more accurate. On the contrary, angiography allows a better visualisation of the extention of intercranial circles. These data show that the Doppler and angiographic techniques are complementary one to the other in the study of the collateral circles.

  9. Detectors - Electronics

    International Nuclear Information System (INIS)

    Bregeault, J.; Gabriel, J.L.; Hierle, G.; Lebotlan, P.; Leconte, A.; Lelandais, J.; Mosrin, P.; Munsch, P.; Saur, H.; Tillier, J.

    1998-01-01

    The reports presents the main results obtained in the fields of radiation detectors and associated electronics. In the domain of X-ray gas detectors for the keV range efforts were undertaken to rise the detector efficiency. Multiple gap parallel plate chambers of different types as well as different types of X → e - converters were tested to improve the efficiency (values of 2.4% at 60 KeV were reached). In the field of scintillators a study of new crystals has been carried out (among which Lutetium orthosilicate). CdTe diode strips for obtaining X-ray imaging were studied. The complete study of a linear array of 8 CdTe pixels has been performed and certified. The results are encouraging and point to this method as a satisfying solution. Also, a large dimension programmable chamber was used to study the influence of temperature on the inorganic scintillators in an interval from -40 deg. C to +150 deg. C. Temperature effects on other detectors and electronic circuits were also investigated. In the report mentioned is also the work carried out for the realization of the DEMON neutron multidetector. For neutron halo experiments different large area Si detectors associated with solid and gas position detectors were realized. In the frame of a contract with COGEMA a systematic study of Li doped glasses was undertaken aiming at replacing with a neutron probe the 3 He counters presently utilized in pollution monitoring. An industrial prototype has been realised. Other studies were related to integrated analog chains, materials for Cherenkov detectors, scintillation probes for experiments on fundamental processes, gas position sensitive detectors, etc. In the field of associated electronics there are mentioned the works related to the multidetector INDRA, data acquisition, software gamma spectrometry, automatic gas pressure regulation in detectors, etc

  10. Development of a detector control system for the serially powered ATLAS pixel detector at the HL-LHC

    Energy Technology Data Exchange (ETDEWEB)

    Puellen, Lukas

    2015-02-10

    In the years around 2020 the LHC will be upgraded to the HL-LHC. In terms of this upgrade, the ATLAS detector will also be upgraded. This also includes the pixel detector, the innermost of the sub-detectors in ATLAS. Thereby the powering concept of the pixel detector will be changed to reduce the material budget of the detector. From individual powering of each detector module, the concept changes to serial powering, where all modules of a powering group are connected in series. This change makes the development of a new detector control system (DCS) mandatory. Therefore, a new concept for the ATLAS pixel DCS is being developed at the University of Wuppertal. This concept is split into three paths: a safety path, a control path, and a diagnostics path. The safety path is a hard wired interlock system. The concept of this system will not differ significantly, compared to the interlock system of the current detector. The diagnostics path is embedded into the optical data read-out of the detector and will be used for detector tuning with high precision and granularity. The control path supervises the detector and provides a user interface to the hardware components. A concept for this path, including a prototype and proof-of-principle studies, has been developed in terms of this thesis. The control path consists of the DCS network, a read-out and controlling topology created by two types of ASICs: the DCS controller and the DCS chip. These ASICs measure and control all values, necessary for a safe detector operation in situ. This reduces the number of required cables and hence the material budget of the system. For the communication between these ASICs, two very fault tolerant bus protocols have been chosen: CAN bus carries data from the DCS computers, outside of the detector, to the DCS controllers at the edge of the pixel detector. For the communication between the DCS controller and the DCS chip, which is located close to each detector module, an enhanced I2C

  11. Development of a detector control system for the serially powered ATLAS pixel detector at the HL-LHC

    International Nuclear Information System (INIS)

    Puellen, Lukas

    2015-01-01

    In the years around 2020 the LHC will be upgraded to the HL-LHC. In terms of this upgrade, the ATLAS detector will also be upgraded. This also includes the pixel detector, the innermost of the sub-detectors in ATLAS. Thereby the powering concept of the pixel detector will be changed to reduce the material budget of the detector. From individual powering of each detector module, the concept changes to serial powering, where all modules of a powering group are connected in series. This change makes the development of a new detector control system (DCS) mandatory. Therefore, a new concept for the ATLAS pixel DCS is being developed at the University of Wuppertal. This concept is split into three paths: a safety path, a control path, and a diagnostics path. The safety path is a hard wired interlock system. The concept of this system will not differ significantly, compared to the interlock system of the current detector. The diagnostics path is embedded into the optical data read-out of the detector and will be used for detector tuning with high precision and granularity. The control path supervises the detector and provides a user interface to the hardware components. A concept for this path, including a prototype and proof-of-principle studies, has been developed in terms of this thesis. The control path consists of the DCS network, a read-out and controlling topology created by two types of ASICs: the DCS controller and the DCS chip. These ASICs measure and control all values, necessary for a safe detector operation in situ. This reduces the number of required cables and hence the material budget of the system. For the communication between these ASICs, two very fault tolerant bus protocols have been chosen: CAN bus carries data from the DCS computers, outside of the detector, to the DCS controllers at the edge of the pixel detector. For the communication between the DCS controller and the DCS chip, which is located close to each detector module, an enhanced I2C

  12. Scoliosis in patients with Prader Willi Syndrome – comparisons of conservative and surgical treatment

    Directory of Open Access Journals (Sweden)

    Goodall Deborah

    2009-05-01

    Full Text Available Abstract In children with Prader Willi syndrome (PWS, besides growth hormone (GH therapy, control of the food environment and regular exercise, surgical treatment of scoliosis deformities seems the treatment of choice, even though the risks of spinal surgery in this specific population is very high. Therefore the question arises as to whether the risks of spinal surgery outweigh the benefits in a condition, which bears significant risks per se. The purpose of this systematic review of the Pub Med literature was to find mid or long-term results of spinal fusion surgery in patients with PWS, and to present the conservative treatment in a case study of nine patients with this condition. Methods Types of studies included; all kinds of studies; retrospective and prospective ones, which reported upon the outcome of scoliosis surgery in patients with PWS. Types of participants included: patients with scoliosis and PWS. Type of intervention: surgery. Search strategy for identification of the studies; Pub Med; limited to English language and bibliographies of all reviewed articles. Nine patients with PWS from our data-base treated conservatively have been found, being 19 years or over at the time this study has been performed. The results of conservative management are described and related to the natural history and treatment results found in the Pub Med review. Results From 2210 titles displayed in the Pub Med database with the key word being "Prader Willi syndrome", 5 different papers were displayed at the date of the search containing some information on the outcome of surgery and none appeared to contain a mid or long-term follow-up. The PWS patients treated conservatively from our series all stayed below 70° and some of which improved. Discussion If the curve of scoliosis patients with PWS can be kept within certain limits (usually below 70 degrees conservatively, this treatment seems to have fewer complications than surgical treatments. The

  13. Muon-track studies in a water Cherenkov detector

    Energy Technology Data Exchange (ETDEWEB)

    Etchegoyen, A. [Departamento de Fisica, Comision Nacional de Energia Atomica, Avenida del Libertador 8250 (1429) Buenos Aires (Argentina)]. E-mail: etchegoy@tandar.cnea.gov.ar; Bauleo, P. [Departamento de Fisica, Comision Nacional de Energia Atomica, Avenida del Libertador 8250 (1429) Buenos Aires (Argentina); Bertou, X. [Enrico Fermfi Institute, University of Chicago, 5640 S. Ellis, Chicago, IL 60637 (United States); Bonifazi, C.B. [Departamento de Fisica, Comision Nacional de Energia Atomica, Avenida del Libertador 8250 (1429) Buenos Aires (Argentina); Filevich, A. [Departamento de Fisica, Comision Nacional de Energia Atomica, Avenida del Libertador 8250 (1429) Buenos Aires (Argentina); Medina, M.C. [Departamento de Fisica, Comision Nacional de Energia Atomica, Avenida del Libertador 8250 (1429) Buenos Aires (Argentina); Melo, D.G. [Departamento de Fisica, Comision Nacional de Energia Atomica, Avenida del Libertador 8250 (1429) Buenos Aires (Argentina); Rovero, A.C. [Instituto de Astronomia y Fisica del Espacio, CC 67, Suc. 28 (1428) Buenos Aires (Argentina); Supanitsky, A.D. [Departamento de Fisica, Comision Nacional de Energia Atomica, Avenida del Libertador 8250 (1429) Buenos Aires (Argentina); Tamashiro, A. [Departamento de Fisica, Comision Nacional de Energia Atomica, Avenida del Libertador 8250 (1429) Buenos Aires (Argentina)

    2005-06-21

    Background muons may be used in cosmic ray experiments to understand the response of a given detector system and to lay the basis for the further theoretical and simulation work needed in the analysis of air showers. Experiments were performed using a water Cherenkov detector at the Tandar Laboratory. Monte Carlo and semi-analytical calculations were compared to the data.

  14. Peltier battery thermostat for semiconductor detectors

    International Nuclear Information System (INIS)

    Caini, V.

    1980-01-01

    The description is given of a Peltier battery cooling thermostat for semiconductor detectors, whose sensing element is the detector itself. A signal proportional to the leakage current is amplified and compared with a chosen reference voltage. The difference, amplified and sensed, regulates the cooling current to the Peltier battery. Special mechanical devices speed up measurement-taking. The leakage current proved to be reducible to as little as 1/1000 of that at ambient temperature and the stabilization obtained is between +-5 nA (although between +-1 nA is also feasible). Hence it is possible to use very high load resistance preamplifiers to reduce noise and to improve stability and pulse height resolution in α spectroscopy, even with a detector unsuitable for work at very low temperatures. Other applications can be foreseen. (orig.)

  15. Comparison of natural and synthetic diamond X-ray detectors

    International Nuclear Information System (INIS)

    Lansley, S. P.; Betzel, G.T.; Meyer, J.; Metcalf, P.; Reinisch, L.

    2010-01-01

    Full text: Diamond detectors are particularly well suited for dosimetry applications in radiotherapy for reasons including near-tissue equivalence and high-spatial resolu tion resulting from small sensitive volumes. However, these detectors have not become commonplace due to high cost and poor availability arising from the need for high quality diamond. We have fabricated relatively cheap detectors from commercially-available synthetic diamond fabricated using chemical vapour deposition. Here, we present a comparison of one of these detectors with the only commercially-available diamond-based detector (which uses a natural diamond crystal). Parameters such as the energy dependence and linearity of charge with dose were investigated at orthovoltage energies (50-250 kY), and dose-rate dependence of charge at linear accelerator energy (6 MY). The energy dependence of a synthetic diamond detector was similar to that of the natural diamond detector, albeit with slightly less variation across the energy range. Both detectors displayed a linear response S. P. Lansley () . G. T. Betzel . J. Meyer Department of Physics and Astronomy, University of Canterbury, Christchurch, New Zealand e-mail: stuart.lansley canterbury.ac.nz S. P. Lansley The Macdiarmid Institute for Advanced Materials and Nanotechnology, University of Canterbury, Christchurch, New Zealand P. Metcalfe Centre for Medical Radiation Physics, University of Wollongong, Wollongong, Australia L. Reinisch Department of Physical and Earth Sciences, Jacksonville State University, Jacksonville, AL, USA with dose (at 100 kY) over the limited dose range used. The sensitivity of the synthetic diamond detector was 302 nC/Gy, compared to 294 nC/Gy measured for the natural diamond detector; however, this was obtained with a bias of 246.50 Y compared to a bias of 61.75 Y used for the natural diamond detector. The natural diamond detector exhibited a greater dependency on dose-rate than the syn thetic diamond detector. Overall

  16. Amorphous silicon/crystalline silicon heterojunctions for nuclear radiation detector applications

    International Nuclear Information System (INIS)

    Walton, J.T.; Hong, W.S.; Luke, P.N.; Wang, N.W.; Ziemba, F.P.

    1996-10-01

    Results on characterization of electrical properties of amorphous Si films for the 3 different growth methods (RF sputtering, PECVD [plasma enhanced], LPCVD [low pressure]) are reported. Performance of these a-Si films as heterojunctions on high resistivity p-type and n- type crystalline Si is examined by measuring the noise, leakage current, and the alpha particle response of 5mm dia detector structures. It is demonstrated that heterojunction detectors formed by RF sputtered films and PECVD films are comparable in performance with conventional surface barrier detectors. Results indicate that the a-Si/c-Si heterojunctions have the potential to greatly simplify detector fabrication. Directions for future avenues of nuclear particle detector development are indicated

  17. Amorphous silicon/crystalline silicon heterojunctions for nuclear radiation detector applications

    International Nuclear Information System (INIS)

    Walton, J.T.; Hong, W.S.; Luke, P.N.; Wang, N.W.; Ziemba, F.P.

    1996-01-01

    Results on the characterization of the electrical properties of amorphous silicon films for the three different growth methods, RF sputtering, PECVD, and LPCVD are reported. The performance of these a-Si films as heterojunctions on high resistivity p-type and n-type crystalline silicon is examined by measuring the noise, leakage current and the alpha particle response of 5 mm diameter detector structures. It is demonstrated that heterojunction detectors formed by RF sputtered films and PECVD films are comparable in performance with conventional surface barrier detectors. The results indicate that the a-Si/c-Si heterojunctions have the potential to greatly simplify detector fabrication. Directions for future avenues of nuclear particle detector development are indicated

  18. Ultrafast secondary emission x-ray imaging detectors

    International Nuclear Information System (INIS)

    Akkerman, A.; Gibrekhterman, A.; Majewski, S.

    1991-07-01

    Fast high accuracy, x-ray imaging at high photon flux can be achieved when coupling thin solid convertors to gaseous electron multipliers, operating at low gas pressures. Secondary electron emitted from the convertor foil are multiplied in several successive amplification elements. The obvious advantage of solid x-ray detectors, as compared to gaseous conversion, are the production of parallax-free images and the fast (subnanoseconds) response. These x-ray detectors have many potential applications in basic and applied research. Of particular interest is the possibility of an efficient and ultrafast high resolution imaging of transition radiation,with a reduced dE/dx background. We present experimental results on the operation of the secondary emission x-ray (SEX) detectors, their detection efficiency, localization and time resolution. The experimental work is accompanied by mathematical modelling and computer simulation of transition radiation detectors based on CsI transition radiation convertors. (author)

  19. Detector with internal gain for short-wave infrared ranging applications

    Science.gov (United States)

    Fathipour, Vala; Mohseni, Hooman

    2017-09-01

    Abstarct.Highly sensitive photon detectors are regarded as the key enabling elements in many applications. Due to the low photon energy at the short-wave infrared (SWIR), photon detection and imaging at this band are very challenging. As such, many efforts in photon detector research are directed toward improving the performance of the photon detectors operating in this wavelength range. To solve these problems, we have developed an electron-injection (EI) technique. The significance of this detection mechanism is that it can provide both high efficiency and high sensitivity at room temperature, a condition that is very difficult to achieve in conventional SWIR detectors. An EI detector offers an overall system-level sensitivity enhancement due to a feedback stabilized internal avalanche-free gain. Devices exhibit an excess noise of unity, operate in linear mode, require bias voltage of a few volts, and have a cutoff wavelength of 1700 nm. We review the material system, operating principle, and development of EI detectors. The shortcomings of the first-generation devices were addressed in the second-generation detectors. Measurement on second-generation devices showed a high-speed response of ˜6 ns rise time, low jitter of less than 20 ps, high amplification of more than 2000 (at optical power levels larger than a few nW), unity excess noise factor, and low leakage current (amplified dark current ˜10 nA at a bias voltage of -3 V and at room temperature. These characteristics make EI detectors a good candidate for high-resolution flash light detection and ranging (LiDAR) applications with millimeter scale depth resolution at longer ranges compared with conventional p-i-n diodes. Based on our experimentally measured device characteristics, we compare the performance of the EI detector with commercially available linear mode InGaAs avalanche photodiode (APD) as well as a p-i-n diode using a theoretical model. Flash LiDAR images obtained by our model show that the EI

  20. Digital signal processors for cryogenic high-resolution x-ray detector readout

    International Nuclear Information System (INIS)

    Friedrich, Stephan; Drury, Owen B.; Bechstein, Sylke; Hennig, Wolfgang; Momayezi, Michael

    2003-01-01

    We are developing fast digital signal processors (DSPs) to read out superconducting high-resolution X-ray detectors with on-line pulse processing. For superconducting tunnel junction (STJ) detector read-out, the DSPs offer online filtering, rise time discrimination and pile-up rejection. Compared to analog pulse processing, DSP readout somewhat degrades the detector resolution, but improves the spectral purity of the detector response. We discuss DSP performance with our 9-channel STJ array for synchrotron-based high-resolution X-ray spectroscopy. (author)

  1. ADC common noise correction and zero suppression in the PIBETA detector

    International Nuclear Information System (INIS)

    Frlez, E.; Pocanic, D.; Ritt, S.

    2001-01-01

    We describe a simple procedure for reducing Analog-to-Digital Converter (ADC) common noise in modular detectors that does not require additional hardware. A method using detector noise groups should work well for modular particle detectors such as segmented electromagnetic calorimeters, plastic scintillator hodoscopes, cathode strip wire chambers, segmented active targets, and the like. We demonstrate a 'second pedestal noise correction' method by comparing representative ADC pedestal spectra for various elements of the PIBETA detector before and after the applied correction

  2. ''In situ'' electronic testing method of a neutron detector performance

    International Nuclear Information System (INIS)

    Gonzalez, J.M.; Levai, F.

    1987-01-01

    The method allows detection of any important change in the electrical characteristics of a neutron sensor channel. It checks the response signal produced by an electronic detector circuit when a pulse generator is connected as input signal in the high voltage supply. The electronic circuit compares the detector capacitance value, previously measured, against a reference value, which is adjusted in a window type comparator electronic circuit to detect any important degrading condition of the capacitance value in a detector-cable system. The ''in-situ'' electronic testing method of neutron detector performance has been verified in a laboratory atmosphere to be a potential method to detect any significant change in the capacitance value of a nuclear sensor and its connecting cable, also checking: detector disconnections, cable disconnections, length changes of the connecting cable, electric short-opened circuits in the sensor channel, and any electrical trouble in the detector-connector-cable system. The experimental practices were carried out by simulation of several electric changes in a nuclear sensor-cable system from a linear D.C. channel which measures reactor power during nuclear reactor operation. It was made at the Training Reactor Electronic Laboratory. The results and conclusions obtained at the Laboratory were proved, satisfactorily, in the Electronic Instrumentation of Budapest Technical University Training Reactor, Hungary

  3. Novel Front-end Electronics for Time Projection Chamber Detectors

    CERN Document Server

    García García, Eduardo José

    This work has been carried out in the European Organization for Nuclear Research (CERN) and it was supported by the European Union as part of the research and development towards the European detector the (EUDET) project, specifically for the International Linear Collider (ILC). In particle physics there are several different categories of particle detectors. The presented design is focused on a particular kind of tracking detector called Time Projection Chamber (TPC). The TPC provides a three dimensional image of electrically charged particles crossing a gaseous volume. The thesis includes a study of the requirements for future TPC detectors summarizing the parameters that the front-end readout electronics must fulfill. In addition, these requirements are compared with respect to the readouts used in existing TPC detectors. It is concluded that none of the existing front-end readout designs fulfill the stringent requirements. The main requirements for future TPC detectors are high integration, an increased n...

  4. GaAs strip detectors: the Australian production program

    International Nuclear Information System (INIS)

    Butcher, K.S.A.; Alexiev, D.

    1995-01-01

    The Australian High Energy Physics consortium (composed of the University of Melbourne, the University of Sydney and ANSTO) has been investigating the possibility of producing a large area wheel of SI GaAs detectors for the ATLAS detector array. To help assess the extent of Australia's role in this venture a few SI GaAs microstrip detectors are to be manufactured under contract by the CSIRO division of Radiophysics GaAs IC Prototyping Facility. The planned production of the devices is discussed. First, the reasons for producing the detectors here in Australia are examined, then some basic characteristics of the material are considered, and finally details are provided of the design used for the manufacture of the devices. Two sets of detectors will be produced using the standard Glasgow production recipe; SIGaAs and GaN. The Glasgow mask set is being used as a benchmark against which to compare the Australian devices

  5. Thermally stimulated investigations on diamond X-Ray detectors

    International Nuclear Information System (INIS)

    Tromson, D.; Bergonzo, P.; Brambilla, A.; Mer, C.; Foulon, F.; Amosov, V.N.

    1999-01-01

    Intrinsic diamond material is increasingly used for the fabrication of radiation detectors. However, the presence of inherent defects has a strong impact on the detector characteristics such as the time dependent stability of the detection signal. In order to draw better insights into this effect, comparative investigations of the X-ray responses with thermally stimulated current (TSC) measurements were carried out on natural diamond detectors. TSC revealed the presence of four peaks or shoulders on natural samples in the 200 to 500 K domain. Three energy levels were identified at about 0.7, 0.71 and 0.95 eV. Time dependent X-ray detector sensitivity was investigated for various initial conditions. The results give evidence of the improvement of the detection properties after having filled traps in the material by X-ray irradiation. The comparison between the X-ray response and the TSC spectra indicate that trapping levels emptied at room temperature appear to significantly affect the performance of radiation detectors. (authors)

  6. The Effect of Early Political Opinion and the Political Positions on Willy Brandt's Policy towards America

    Directory of Open Access Journals (Sweden)

    Judith Michel

    2011-05-01

    Full Text Available Based on two case studies and using the hermeneutic interpretation of sources, this paper analyzes how Willy BRANDT's early political and cultural orientation and his respective political offices influenced his policy towards the United States of America. The example of the Vietnam war illustrates that his early biographical conditioning, as well as his government office, caused him to restrain from public criticism of American involvement in Southeast Asia. As an elder statesman, after leaving the office of Federal Chancellor, some of the orientations which he had developed during the early phase of the Cold War faded into the background while other early conditionings gained new strength in a modified form. He now took a much more critical line on the American policy towards Latin America which was consistent with his aims as Chairman of the "North-South-Commission" and President of the Socialist International. URN: http://nbn-resolving.de/urn:nbn:de:0114-fqs1102122

  7. Detector Control System for the AFP detector in ATLAS experiment at CERN

    Science.gov (United States)

    Banaś, E.; Caforio, D.; Czekierda, S.; Hajduk, Z.; Olszowska, J.; Seabra, L.; Šícho, P.

    2017-10-01

    The ATLAS Forward Proton (AFP) detector consists of two forward detectors located at 205 m and 217 m on either side of the ATLAS experiment. The aim is to measure the momenta and angles of diffractively scattered protons. In 2016, two detector stations on one side of the ATLAS interaction point were installed and commissioned. The detector infrastructure and necessary services were installed and are supervised by the Detector Control System (DCS), which is responsible for the coherent and safe operation of the detector. A large variety of used equipment represents a considerable challenge for the AFP DCS design. Industrial Supervisory Control and Data Acquisition (SCADA) product Siemens WinCCOA, together with the CERN Joint Control Project (JCOP) framework and standard industrial and custom developed server applications and protocols are used for reading, processing, monitoring and archiving of the detector parameters. Graphical user interfaces allow for overall detector operation and visualization of the detector status. Parameters, important for the detector safety, are used for alert generation and interlock mechanisms.

  8. Silicon Telescope Detectors

    CERN Document Server

    Gurov, Yu B; Sandukovsky, V G; Yurkovski, J

    2005-01-01

    The results of research and development of special silicon detectors with a large active area ($> 8 cm^{2}$) for multilayer telescope spectrometers (fulfilled in the Laboratory of Nuclear Problems, JINR) are reviewed. The detector parameters are listed. The production of totally depleted surface barrier detectors (identifiers) operating under bias voltage two to three times higher than depletion voltage is described. The possibility of fabrication of lithium drifted counters with a very thin entrance window on the diffusion side of the detector (about 10--20 $\\mu$m) is shown. The detector fabrication technique has allowed minimizing detector dead regions without degradation of their spectroscopic characteristics and reliability during long time operation in charge particle beams.

  9. The 150 ns detector project: progress with small detectors

    International Nuclear Information System (INIS)

    Warburton, W.K.; Russell, S.R.; Kleinfelder, Stuart A.; Segal, Julie

    1994-01-01

    This project's long term goal is to develop a pixel area detector capable of 6 MHz frame rates (150 ns/frame). Our milestones toward this goal are: a single pixel, 1x256 1D and 8x8 2D detectors, 256x256 2D detectors and, finally, 1024x1024 2D detectors. The design strategy is to supply a complete electronics chain (resetting preamp, selectable gain amplifier, analog-to-digital converter (ADC), and memory) for each pixel. In the final detectors these will all be custom integrated circuits. The front end preamplifiers are being integrated first, since their design and performance are both the most unusual and also critical to the project's success. Similarly, our early work is also concentrating on devising and perfecting detector structures which are thick enough (1 mm) to absorb over 99% of the incident X-rays in the energy range of interest. In this paper we discuss our progress toward the 1x256 1D and 8x8 2D detectors. We have fabricated sample detectors at Stanford's Center for Integrated Systems and are preparing both to test them individually and to wirebond them to the preamplifier samples to produce our first working small 1D and 2D detectors. We will describe our solutions to the design problems associated with collecting charge in less than 30 ns from 1 mm thick pixels in high resistivity silicon. We have constructed and tested the front end of our preamplifier design using a commercial 1.2 μm CMOS technology and are moving on to produce a few channels of the complete preamplifier, including a switchable gain stage and output stage. We will discuss both the preamplifier design and our initial test results. ((orig.))

  10. The 150 ns detector project: progress with small detectors

    Energy Technology Data Exchange (ETDEWEB)

    Warburton, W.K. (X-ray Instrumentation Associates, 2513 Charleston Rd, Ste 207, Mountain View, CA 94043 (United States)); Russell, S.R. (X-ray Instrumentation Associates, 2513 Charleston Rd, Ste 207, Mountain View, CA 94043 (United States)); Kleinfelder, Stuart A. (VLSI Physics, 19 Drury Lane, Berkeley, CA 94705 (United States)); Segal, Julie (Integrated Ckts Lab., Dept. of Electrical Engineering, Stanford University, Stanford, CA 94305 (United States))

    1994-09-01

    This project's long term goal is to develop a pixel area detector capable of 6 MHz frame rates (150 ns/frame). Our milestones toward this goal are: a single pixel, 1x256 1D and 8x8 2D detectors, 256x256 2D detectors and, finally, 1024x1024 2D detectors. The design strategy is to supply a complete electronics chain (resetting preamp, selectable gain amplifier, analog-to-digital converter (ADC), and memory) for each pixel. In the final detectors these will all be custom integrated circuits. The front end preamplifiers are being integrated first, since their design and performance are both the most unusual and also critical to the project's success. Similarly, our early work is also concentrating on devising and perfecting detector structures which are thick enough (1 mm) to absorb over 99% of the incident X-rays in the energy range of interest. In this paper we discuss our progress toward the 1x256 1D and 8x8 2D detectors. We have fabricated sample detectors at Stanford's Center for Integrated Systems and are preparing both to test them individually and to wirebond them to the preamplifier samples to produce our first working small 1D and 2D detectors. We will describe our solutions to the design problems associated with collecting charge in less than 30 ns from 1 mm thick pixels in high resistivity silicon. We have constructed and tested the front end of our preamplifier design using a commercial 1.2 [mu]m CMOS technology and are moving on to produce a few channels of the complete preamplifier, including a switchable gain stage and output stage. We will discuss both the preamplifier design and our initial test results. ((orig.))

  11. (99m)Tc-MDP bone scintigraphy of the hand: comparing the use of novel cadmium zinc telluride (CZT) and routine NaI(Tl) detectors.

    Science.gov (United States)

    Koulikov, Victoria; Lerman, Hedva; Kesler, Mikhail; Even-Sapir, Einat

    2015-12-01

    Cadmium zinc telluride (CZT) solid-state detectors have been recently introduced in the field of nuclear medicine in cardiology and breast imaging. The aim of the current study was to evaluate the performance of the novel detectors (CZT) compared to that of the routine NaI(Tl) in bone scintigraphy. A dual-headed CZT-based camera dedicated originally to breast imaging has been used, and in view of the limited size of the detectors, the hands were chosen as the organ for assessment. This is a clinical study. Fifty-eight consecutive patients (total 116 hands) referred for bone scan for suspected hand pathology gave their informed consent to have two acquisitions, using the routine camera and the CZT-based camera. The latter was divided into full-dose full-acquisition time (FD CZT) and reduced-dose short-acquisition time (RD CZT) on CZT technology, so three image sets were available for analysis. Data analysis included comparing the detection of hot lesions and identification of the metacarpophalangeal, proximal interphalangeal, and distal interphalangeal joints. A total of 69 hot lesions were detected on the CZT image sets; of these, 61 were identified as focal sites of uptake on NaI(Tl) data. On FD CZT data, 385 joints were identified compared to 168 on NaI(Tl) data (p < 0.001). There was no statistically significant difference in delineation of joints between FD and RD CZT data as the latter identified 383 joints. Bone scintigraphy using a CZT-based gamma camera is associated with improved lesion detection and anatomic definition. The superior physical characteristics of this technique raised a potential reduction in administered dose and/or acquisition time without compromising image quality.

  12. Assessment of MicroDiamond PTW 60019 detector and its comparison with other detectors for relative dosimetry in small radiosurgery fields of the Leksell gamma knife perfexion

    International Nuclear Information System (INIS)

    Novotny, J. Jr.; Kozubikova, P.; Pastykova, V.; Pipek, J.; Bhatnagar, J. P.; Huq, M. S.; Veselsky, T.

    2014-01-01

    Measurement of relative output factors (ROF) for the Leksell Gamma Knife (LGK) is not a trivial task due to strict demands of an accurate set up and small size of measured radiosurgery fields. The purpose of this study was to perform an assessment of a new synthetic single crystal MicroDiamond PTW 60019 detector (volume 0.004 mm 3 ) for measurement of ROFs for 4 mm and 8 mm collimators for the LGK Perfexion. Small sensitive volume of this detector, near water equivalence and low energy dependence make it an attractive candidate for small field dosimetry. Results obtained in this study were compared with results measured by broad variety of different detectors and also Monte Carlo (MC) simulation. MicroDiamond detector connected to PTW UNIDOS electrometer was positioned in ELEKTA spherical phantom and pre-irradiated to dose of 5 Gy. Measurements were performed in two different detector positions: 1) parallel with table axis, 2) orthogonal to table axis. Electrometer timer of 1 min was used to measure subsequently signal from 16 mm, 8 mm and 4 mm beams. Altogether ten measurements were performed for each of three collimator sizes. Results from MicroDiamond were compared with those obtained from various types of detectors used in the past by authors for measurement of LGK ROFs. New synthetic single crystal MicroDiamond PTW 60019 detector appears to be a very promising detector for relative output factor measurements in very small radiosurgery fields. (authors)

  13. SU-E-T-485: Investigation of a Synthetic Diamond Detector for Tomotherapy Dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Knill, C; Nalichowski, A; Halford, R [Karmanos Cancer Institute, Detroit, MI (United States); Zakjevskii, V; Zhuang, L [Wayne State University School of Medicine, Detroit, MI (United States); Snyder, M; Burmeister, J [Karmanos Cancer Institute, Detroit, MI (United States); Wayne State University School of Medicine, Detroit, MI (United States)

    2014-06-01

    Purpose: Tomotherapy treatments are characterized by rotational deliveries of flattening-filter free fields resulting in high-gradient dose distributions. Small volume, rotationally independent detectors are needed for accurate dosimetry. PTWs microDiamond detector, with its small sensitive volume (0.004mm{sup 3}), could potentially be an ideal detector for Tomotherapy. The microDiamond detector was tested against a small volume Exradin A1SL ion chamber for Tomotherapy open-field and IMRT commissioning measurements. Methods: Custom detector holders were fabricated to allow A1SL and microDiamond measurements in the Tomotherapy Cheese phantom and a square solid water phantom. The microDiamond rotational dependence within the Tomotherapy phantom was tested by incrementally rotating the detector in between static-gantry angle Tomotherapy irradiations. Longitudinal Tomotherapy profiles, for all field sizes, were measured with the microDiamond and A1SL detectors at 1.5cm depth in the square phantom, and compared to film. Detector axes were aligned parallel to table motion. Per TG-119 recommendations, both detectors were calibrated to known doses in phantoms and used to measure high-dose points in TG-119 H and N and Prostate plans. The measurements were compared to the treatment planning system and subsequently compared to published TG-119 confidence limits. Results: The microDiamond angular dependence was less than 0.5%. The average difference between the detectors and film-measured longitudinal profile 80–20% penumbras were 0.03+/-0.04mm and 1.36+/-0.22mm for the microDiamond and A1SL, respectively. The average difference between the detector and filmmeasured field sizes were 0.07+/-0.01mm and 0.09+/-0.02mm for the microDiamond and A1SL, respectively. The measured confidence limits were 0.023 and 0.015 for microDiamond and A1SL, respectively. TG-119 reported a confidence limit of 0.034. Conclusion: The microDiamond measured open-field longitudinal Tomotherapy profiles

  14. Characterization of DECam focal plane detectors

    Energy Technology Data Exchange (ETDEWEB)

    Diehl, H.Thomas; Angstadt, Robert; Campa, Julia; Cease, Herman; Derylo, Greg; Emes, John H.; Estrada, Juan; Kibik, Donna; Flaugher, Brenna L.; Holland, Steve E.; Jonas, Michelle; /Fermilab /Madrid, CIEMAT /LBL, Berkeley /Argonne /Pennsylvania U.

    2008-06-01

    DECam is a 520 Mpix, 3 square-deg FOV imager being built for the Blanco 4m Telescope at CTIO. This facility instrument will be used for the 'Dark Energy Survey' of the southern galactic cap. DECam has chosen 250 ?m thick CCDs, developed at LBNL, with good QE in the near IR for the focal plane. In this work we present the characterization of these detectors done by the DES team, and compare it to the DECam technical requirements. The results demonstrate that the detectors satisfy the needs for instrument.

  15. Solid-state, flat-panel, digital radiography detectors and their physical imaging characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Cowen, A.R. [LXi Research, Academic Unit of Medical Physics, University of Leeds, West Yorkshire (United Kingdom)], E-mail: a.r.cowen@leeds.ac.uk; Kengyelics, S.M.; Davies, A.G. [LXi Research, Academic Unit of Medical Physics, University of Leeds, West Yorkshire (United Kingdom)

    2008-05-15

    Solid-state, digital radiography (DR) detectors, designed specifically for standard projection radiography, emerged just before the turn of the millennium. This new generation of digital image detector comprises a thin layer of x-ray absorptive material combined with an electronic active matrix array fabricated in a thin film of hydrogenated amorphous silicon (a-Si:H). DR detectors can offer both efficient (low-dose) x-ray image acquisition plus on-line readout of the latent image as electronic data. To date, solid-state, flat-panel, DR detectors have come in two principal designs, the indirect-conversion (x-ray scintillator-based) and the direct-conversion (x-ray photoconductor-based) types. This review describes the underlying principles and enabling technologies exploited by these designs of detector, and evaluates their physical imaging characteristics, comparing performance both against each other and computed radiography (CR). In standard projection radiography indirect conversion DR detectors currently offer superior physical image quality and dose efficiency compared with direct conversion DR and modern point-scan CR. These conclusions have been confirmed in the findings of clinical evaluations of DR detectors. Future trends in solid-state DR detector technologies are also briefly considered. Salient innovations include WiFi-enabled, portable DR detectors, improvements in x-ray absorber layers and developments in alternative electronic media to a-Si:H.

  16. Impaired theory of mind and symptoms of Autism Spectrum Disorder in children with Prader-Willi syndrome.

    Science.gov (United States)

    Lo, Sin Ting; Siemensma, Elbrich; Collin, Philippe; Hokken-Koelega, Anita

    2013-09-01

    In order to evaluate the social cognitive functioning in children with Prader-Willi syndrome (PWS), Theory of Mind (ToM) and symptoms of Autism Spectrum Disorder were evaluated. Sixty-six children with PWS aged 7-17 years were tested using the Theory of Mind test-R and the Diagnostic Interview for Social Communication disorders. We tested the correlation between Total ToM Standard Deviation Score (Total ToM SDS) and genetic subtype of paternal deletion or maternal uniparental disomy, and total IQ, verbal IQ and performal IQ. Prevalence and symptoms of Autism Spectrum Disorder were assessed. Median (interquartile range) of total ToM SDS of those aged 7-17 years was -3.84 (-5.73, -1.57). Their Total ToM SDS correlated with total IQ (β=0.662, p0.05, adj.R(2)=0.259). No difference in Total ToM SDS was found between children with deletion and maternal uniparental disomy (β=-0.143, p>0.05, adj.R(2)=-0.016). Compared to the reference group of healthy children aged 7-12 years, children with PWS in the same age group had a median ToM developmental delay of 4 (3-5) years. One third of children with PWS scored positive for Autism Spectrum Disorder. Most prominent aberrations in Autism Spectrum Disorder were focused on maladaptive behavior. Our findings demonstrate a markedly reduced level of social cognitive functioning, which has consequences for the approach of children with PWS, i.e. adjustment to the child's level of social cognitive functioning. Copyright © 2013 Elsevier Ltd. All rights reserved.

  17. A reduced-energy intake, well-balanced diet improves weight control in children with Prader-Willi syndrome.

    Science.gov (United States)

    Miller, J L; Lynn, C H; Shuster, J; Driscoll, D J

    2013-02-01

    Children with Prader-Willi syndrome (PWS) have a predictable pattern of weight gain, with obesity beginning in early childhood and worsening as they get older and hyperphagia increases. Data on the most effective dietary modifications are scant and primarily anecdotal. As part of a longitudinal study investigating the natural history of PWS, we evaluated the effect of a well-balanced, energy-restricted diet on body composition and weight in young children with PWS. Sixty-three children, aged 2-10 years, with genetically proven PWS participated in the present study. These children had measurements of body composition by dual-energy X-ray absorptiometry and resting energy expenditure (REE), as well as a 3-day diet history analysis both before and after intervention. Energy calculations were based on the individual's REE, with the recommendation that the macronutrients of the diet consist of 30% fat, 45% carbohydrates and 25% protein, with at least 20 g of fibre per day. Thirty-three families adhered to our dietary recommendations for both energy intake and macronutrient distribution. Those 33 children had lower body fat (19.8% versus 41.9%; P diet. Those who followed our recommendations also had a lower respiratory quotient (0.84 versus 0.95; P = 0.002). Our recommendation for an energy-restricted diet with a well-balanced macronutrient composition and fibre intake improves both weight and body composition in children with PWS compared to a simple energy-restricted diet. © 2012 The Authors. Journal of Human Nutrition and Dietetics © 2012 The British Dietetic Association Ltd.

  18. High-energy detector

    Science.gov (United States)

    Bolotnikov, Aleksey E [South Setauket, NY; Camarda, Giuseppe [Farmingville, NY; Cui, Yonggang [Upton, NY; James, Ralph B [Ridge, NY

    2011-11-22

    The preferred embodiments are directed to a high-energy detector that is electrically shielded using an anode, a cathode, and a conducting shield to substantially reduce or eliminate electrically unshielded area. The anode and the cathode are disposed at opposite ends of the detector and the conducting shield substantially surrounds at least a portion of the longitudinal surface of the detector. The conducting shield extends longitudinally to the anode end of the detector and substantially surrounds at least a portion of the detector. Signals read from one or more of the anode, cathode, and conducting shield can be used to determine the number of electrons that are liberated as a result of high-energy particles impinge on the detector. A correction technique can be implemented to correct for liberated electron that become trapped to improve the energy resolution of the high-energy detectors disclosed herein.

  19. Nuclear radiation detectors

    International Nuclear Information System (INIS)

    Kapoor, S.S.; Ramamurthy, V.S.

    1986-01-01

    The present monograph is intended to treat the commonly used detectors in the field of nuclear physics covering important developments of the recent years. After a general introduction, a brief account of interaction of radiation with matter relevant to the processes in radiation detection is given in Chapter II. In addition to the ionization chamber, proportional counters and Geiger Mueller counters, several gas-filled detectors of advanced design such as those recently developed for heavy ion physics and other types of studies have been covered in Chapter III. Semiconductor detectors are dealt with in Chapter IV. The scintillation detectors which function by sensing the photons emitted by the luminescence process during the interaction of the impinging radiation with the scintillation detector medium are described in Chapter V. The topic of neutron detectors is covered in Chapter VI, as in this case the emphasis is more on the method of neutron detection rather than on detector type. Electronic instrumentation related to signal pulse processing dealt with in Chapter VII. The track etch detectors based on the visualization of the track of the impinging charge particle have also been briefly covered in the last chapter. The scope of this monograph is confined to detectors commonly used in low and medium energy nuclear physics research and applications of nuclear techniques. The monograph is intended for post-graduate students and those beginning to work with the radiation detectors. (author)

  20. Neutron detection at jet using artificial diamond detectors

    International Nuclear Information System (INIS)

    Pillon, M.; Angelone, M.; Lattanzi, D.; Marinelli, M.; Milani, E.; Tucciarone, A.; Verona-Rinati, G.; Popovichev, S.; Montereali, R.M.; Vincenti, M.A.; Murari, A.

    2007-01-01

    Artificial diamond neutron detectors recently proved to be promising devices to measure the neutron production on large experimental fusion machines. Diamond detectors are very promising detectors to be used in fusion environment due to their radiation hardness, low sensitivity to gamma rays, fast response and high energy resolution. High quality 'electronic grade' diamond films are produced through microwave chemical vapour deposition (CVD) technique. Two CVD diamond detectors have been installed and operated at joint European torus (JET), Culham Science Centre, UK. One of these detectors was a polycrystalline CVD diamond film; about 12 mm 2 area and 30 μm thickness while the second was a monocrystalline film of about 5 mm 2 area and 20 μm thick. Both diamonds were covered with 2 μm of lithium fluoride (LiF) 95% enriched in 6 Li. The LiF layer works as a neutron-to-charged particle converter so these detectors can measure thermalized neutrons. Their output signals were compared to JET total neutron yield monitors (KN1 diagnostic) realized with a set of uranium fission chambers. Despite their small active volumes the diamond detectors were able to measure total neutron yields with good reliability and stability during the recent JET experimental campaign of 2006

  1. Measurement of indoor radon concentration by CR-39 track detector

    International Nuclear Information System (INIS)

    Yamamoto, Masayoshi; Yoneda, Shigeru; Nakanishi, Takashi.

    1990-01-01

    A convenient and cheap method for measuring indoor radon ( 222 Rn) concentration with a CR-39 track detector is described. The detector consisted of two sheets of CR-39 enclosed separately in two plastic pots : one covered by a filter (cup method) and another no covering (bare method). The bare method was used here to supplement the cup method. To compare with the result of the CR-39 detector, alpha-ray spectrometry was carried out with a Si(Au) detector in a controlled radon exposure chamber. Indoor radon concentration measured in 133 houses in several districts of Ishikawa Prefecture have been found to range from 6 Bq/m 3 to as high as 113 Bq/m 3 with a median value of 24 Bq/m 3 . The problems to measure indoor radon concentration using the CR-39 detector are also discussed with emphasis on the position of setting the detector in the room and the possible thoron contribution to the detector. (author)

  2. Radiation detectors laboratory

    International Nuclear Information System (INIS)

    Ramirez J, F.J.

    1997-01-01

    The Radiation detectors laboratory was established with the assistance of the International Atomic Energy Agency which gave this the responsibility to provide its services at National and regional level for Latin America and it is located at the ININ. The more expensive and delicate radiation detectors are those made of semiconductor, so it has been put emphasis in the use and repairing of these detectors type. The supplied services by this laboratory are: selection consultant, detectors installation and handling and associated systems. Installation training, preventive and corrective maintenance of detectors and detection systems calibration. (Author)

  3. MUON DETECTORS: ALIGNMENT

    CERN Multimedia

    G.Gomez

    Since September, the muon alignment system shifted from a mode of hardware installation and commissioning to operation and data taking. All three optical subsystems (Barrel, Endcap and Link alignment) have recorded data before, during and after CRAFT, at different magnetic fields and during ramps of the magnet. This first data taking experience has several interesting goals: •    study detector deformations and movements under the influence of the huge magnetic forces; •    study the stability of detector structures and of the alignment system over long periods, •    study geometry reproducibility at equal fields (specially at 0T and 3.8T); •    reconstruct B=0T geometry and compare to nominal/survey geometries; •    reconstruct B=3.8T geometry and provide DT and CSC alignment records for CMSSW. However, the main goal is to recons...

  4. Divergent structural brain abnormalities between different genetic subtypes of children with Prader-Willi syndrome.

    Science.gov (United States)

    Lukoshe, Akvile; White, Tonya; Schmidt, Marcus N; van der Lugt, Aad; Hokken-Koelega, Anita C

    2013-10-22

    Prader-Willi syndrome (PWS) is a complex neurogenetic disorder with symptoms that indicate not only hypothalamic, but also a global, central nervous system (CNS) dysfunction. However, little is known about developmental differences in brain structure in children with PWS. Thus, our aim was to investigate global brain morphology in children with PWS, including the comparison between different genetic subtypes of PWS. In addition, we performed exploratory cortical and subcortical focal analyses. High resolution structural magnetic resonance images were acquired in 20 children with genetically confirmed PWS (11 children carrying a deletion (DEL), 9 children with maternal uniparental disomy (mUPD)), and compared with 11 age- and gender-matched typically developing siblings as controls. Brain morphology measures were obtained using the FreeSurfer software suite. Both children with DEL and mUPD showed smaller brainstem volume, and a trend towards smaller cortical surface area and white matter volume. Children with mUPD had enlarged lateral ventricles and larger cortical cerebrospinal fluid (CSF) volume. Further, a trend towards increased cortical thickness was found in children with mUPD. Children with DEL had a smaller cerebellum, and smaller cortical and subcortical grey matter volumes. Focal analyses revealed smaller white matter volumes in left superior and bilateral inferior frontal gyri, right cingulate cortex, and bilateral precuneus areas associated with the default mode network (DMN) in children with mUPD. Children with PWS show signs of impaired brain growth. Those with mUPD show signs of early brain atrophy. In contrast, children with DEL show signs of fundamentally arrested, although not deviant brain development and presented few signs of cortical atrophy. Our results of global brain measurements suggest divergent neurodevelopmental patterns in children with DEL and mUPD.

  5. The Silicon Ministrip Detector of the DELPHI Very Forward Tracker

    CERN Document Server

    AUTHOR|(CDS)2067985

    1996-01-01

    The subject of this work is the design, test and construction of a new silicon tracking detector for the extreme forward region of the DELPHI experiment at LEP. I joined the Very Forward Tracker (VFT) Ministrip group in 1993, at a time when the upgrade of the DELPHI tracking system was proposed. My first task was to participate in the design of the ministrip detector for the VFT. This included the optimisation of the detector layout in simulations and the study of prototype detectors in the testbeam. In 1994 I became responsible for the tests and assembly' of the VFT ministrip detector at CERN. The main focus of my work was the study of the performance of a large variety of detectors in beam tests. This included the preparation of the test setup, the tests of different detectors and the analysis of the measurements. With these measurements it is possible to compare the advantages and disadvantages of various new layouts for large pitch silicon strip detectors. In particular the signal response and spatial res...

  6. Lack of Postprandial Peak in Brain-Derived Neurotrophic Factor in Adults with Prader-Willi Syndrome.

    Directory of Open Access Journals (Sweden)

    Marta Bueno

    Full Text Available Prader-Willi syndrome (PWS is characterized by severe hyperphagia. Brain-derived neurotrophic factor (BDNF and leptin are reciprocally involved in energy homeostasis.To analyze the role of BDNF and leptin in satiety in genetic subtypes of PWS.Experimental study.University hospital.90 adults: 30 PWS patients; 30 age-sex-BMI-matched obese controls; and 30 age-sex-matched lean controls.Subjects ingested a liquid meal after fasting ≥10 hours.Leptin and BDNF levels in plasma extracted before ingestion and 30', 60', and 120' after ingestion. Hunger, measured on a 100-point visual analogue scale before ingestion and 60' and 120' after ingestion.Fasting BDNF levels were lower in PWS than in controls (p = 0.05. Postprandially, PWS patients showed only a truncated early peak in BDNF, and their BDNF levels at 60' and 120' were lower compared with lean controls (p<0.05. Leptin was higher in PWS patients than in controls at all time points (p<0.001. PWS patients were hungrier than controls before and after eating. The probability of being hungry was associated with baseline BDNF levels: every 50-unit increment in BDNF decreased the odds of being hungry by 22% (OR: 0.78, 95%CI: 0.65-0.94. In uniparental disomy, the odds of being hungry decreased by 66% (OR: 0.34, 90%CI: 0.13-0.9. Postprandial leptin patterns did no differ among genetic subtypes.Low baseline BDNF levels and lack of postprandial peak may contribute to persistent hunger after meals. Uniparental disomy is the genetic subtype of PWS least affected by these factors.

  7. The High Direct Medical Costs of Prader-Willi Syndrome.

    Science.gov (United States)

    Shoffstall, Andrew J; Gaebler, Julia A; Kreher, Nerissa C; Niecko, Timothy; Douglas, Diah; Strong, Theresa V; Miller, Jennifer L; Stafford, Diane E; Butler, Merlin G

    2016-08-01

    To assess medical resource utilization associated with Prader-Willi syndrome (PWS) in the US, hypothesized to be greater relative to a matched control group without PWS. We used a retrospective case-matched control design and longitudinal US administrative claims data (MarketScan) during a 5-year enrollment period (2009-2014). Patients with PWS were identified by Classification of Diseases, Ninth Revision, Clinical Modification diagnosis code 759.81. Controls were matched on age, sex, and payer type. Outcomes included total, outpatient, inpatient and prescription costs. After matching and application of inclusion/exclusion criteria, we identified 2030 patients with PWS (1161 commercial, 38 Medicare supplemental, and 831 Medicaid). Commercially insured patients with PWS (median age 10 years) had 8.8-times greater total annual direct medical costs than their counterparts without PWS (median age 10 years: median costs $14 907 vs $819; P < .0001; mean costs: $28 712 vs $3246). Outpatient care comprised the largest portion of medical resource utilization for enrollees with and without PWS (median $5605 vs $675; P < .0001; mean $11 032 vs $1804), followed by mean annual inpatient and medication costs, which were $10 879 vs $1015 (P < .001) and $6801 vs $428 (P < .001), respectively. Total annual direct medical costs were ∼42% greater for Medicaid-insured patients with PWS than their commercially insured counterparts, an increase partly explained by claims for Medicaid Waiver day and residential habilitation. Direct medical resource utilization was considerably greater among patients with PWS than members without the condition. This study provides a first step toward quantifying the financial burden of PWS posed to individuals, families, and society. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  8. Irisin and the Metabolic Phenotype of Adults with Prader-Willi Syndrome.

    Directory of Open Access Journals (Sweden)

    Harry J Hirsch

    Full Text Available Hyperphagia, low resting energy expenditure, and abnormal body composition contribute to severe obesity in Prader Willi syndrome (PWS. Irisin, a circulating myokine, stimulates "browning" of white adipose tissue resulting in increased energy expenditure and improved insulin sensitivity. Irisin has not been previously studied in PWS.Compare plasma and salivary irisin in PWS adults and normal controls. Examine the relationship of irisin to insulin sensitivity and plasma lipids.A fasting blood sample for glucose, lipids, insulin, leptin, adinopectin, and irisin was obtained from 22 PWS adults and 54 healthy BMI-matched volunteers. Saliva was collected for irisin assay in PWS and controls.Fasting glucose (77 ± 9 vs 83 ± 7 mg/dl, p = 0.004, insulin (4.1 ± 2.0 vs 7.9 ± 4.7 μU/ml, p<0.001, and triglycerides (74 ± 34 vs 109 ± 71 mg/dl, p = 0.007 were lower in PWS than in controls. Insulin resistance (HOMA-IR was lower (0.79 ± 0.041 vs 1.63 ± 1.02, p<0.001 and insulin sensitivity (QUICKI was higher (0.41 ± 0.04 vs 0.36 ± 0.03, p<0.001 in PWS. Plasma irisin was similar in both groups, but salivary irisin (64.5 ± 52.0 vs 33.0 ± 12.1ng/ml, plasma leptin (33.5 ± 24.2 vs 19.7 ± 19.3 ng/ml and plasma adinopectin (13.0 ± 10.8 vs 7.6 ± 4.5μg/ml were significantly greater in PWS (p<0.001. In PWS, plasma irisin showed positive Pearson correlations with total cholesterol (r = 0.58, p = 0.005, LDL-cholesterol (r = 0.59, p = 0.004, and leptin (r = 0.43, p = 0.045. Salivary irisin correlated negatively with HDL-cholesterol (r = -0.50, p = 0.043 and positively with LDL-cholesterol (r = 0.51, p = 0.037 and triglycerides (r = 0.50, p = 0.041.Salivary irisin was markedly elevated in PWS although plasma irisin was similar to levels in controls. Significant associations with plasma lipids suggest that irisin may contribute to the metabolic phenotype of PWS.

  9. He-4 fast neutron detectors in nuclear security applications

    International Nuclear Information System (INIS)

    Murer, D. E.

    2014-01-01

    This work presents studies of "4He fast neutron detectors for nuclear security applications. Such devices are high pressure gas scintillation detectors, sensitive to neutrons in the energy range of fission sources. First, an introduction to the scope of the intended application is given. This is followed by a description of all components relevant to the operation of the detector. The next chapter presents studies of various characteristics of the neutron detector, among them properties of its scintillation response, differences between neutron and gamma interactions and effects of the light collection process. The results of the detector characterization are used to develop neutron gamma discrimination methods. These methods are put to the test using measurements with a high gamma flux, and the results are compared to performance requirements of Radiation Portal Monitors. Background neutron measurements are presented next. Measured neutron rates are compared to values published in scientific literature. The fluctuation of the background count rate was studied, and the contribution of muons evaluated. Two applications of the detectors in the field of nuclear security are discussed in the last two chapters. The first one is a novel method to measure the plutonium mass in a container filled with Mixed Oxide Fuel. The last chapter presents the development of a Radiation Portal Monitor which, in addition to neutron and gamma counting, exploits time correlation to detect threats such as plutonium and "6"0Co. (author)

  10. He-4 fast neutron detectors in nuclear security applications

    Energy Technology Data Exchange (ETDEWEB)

    Murer, D. E.

    2014-07-01

    This work presents studies of {sup 4}He fast neutron detectors for nuclear security applications. Such devices are high pressure gas scintillation detectors, sensitive to neutrons in the energy range of fission sources. First, an introduction to the scope of the intended application is given. This is followed by a description of all components relevant to the operation of the detector. The next chapter presents studies of various characteristics of the neutron detector, among them properties of its scintillation response, differences between neutron and gamma interactions and effects of the light collection process. The results of the detector characterization are used to develop neutron gamma discrimination methods. These methods are put to the test using measurements with a high gamma flux, and the results are compared to performance requirements of Radiation Portal Monitors. Background neutron measurements are presented next. Measured neutron rates are compared to values published in scientific literature. The fluctuation of the background count rate was studied, and the contribution of muons evaluated. Two applications of the detectors in the field of nuclear security are discussed in the last two chapters. The first one is a novel method to measure the plutonium mass in a container filled with Mixed Oxide Fuel. The last chapter presents the development of a Radiation Portal Monitor which, in addition to neutron and gamma counting, exploits time correlation to detect threats such as plutonium and {sup 60}Co. (author)

  11. A minimum bit error-rate detector for amplify and forward relaying systems

    KAUST Repository

    Ahmed, Qasim Zeeshan; Alouini, Mohamed-Slim; Aissa, Sonia

    2012-01-01

    In this paper, a new detector is being proposed for amplify-and-forward (AF) relaying system when communicating with the assistance of L number of relays. The major goal of this detector is to improve the bit error rate (BER) performance of the system. The complexity of the system is further reduced by implementing this detector adaptively. The proposed detector is free from channel estimation. Our results demonstrate that the proposed detector is capable of achieving a gain of more than 1-dB at a BER of 10 -5 as compared to the conventional minimum mean square error detector when communicating over a correlated Rayleigh fading channel. © 2012 IEEE.

  12. A minimum bit error-rate detector for amplify and forward relaying systems

    KAUST Repository

    Ahmed, Qasim Zeeshan

    2012-05-01

    In this paper, a new detector is being proposed for amplify-and-forward (AF) relaying system when communicating with the assistance of L number of relays. The major goal of this detector is to improve the bit error rate (BER) performance of the system. The complexity of the system is further reduced by implementing this detector adaptively. The proposed detector is free from channel estimation. Our results demonstrate that the proposed detector is capable of achieving a gain of more than 1-dB at a BER of 10 -5 as compared to the conventional minimum mean square error detector when communicating over a correlated Rayleigh fading channel. © 2012 IEEE.

  13. Drift Chambers detectors; Detectores de deriva

    Energy Technology Data Exchange (ETDEWEB)

    Duran, I; Martinez laso, L

    1989-07-01

    We present here a review of High Energy Physics detectors based on drift chambers. The ionization, drift diffusion, multiplication and detection principles are described. Most common drift media are analysed, and a classification of the detectors according to its geometry is done. Finally the standard read-out methods are displayed and the limits of the spatial resolution are discussed. (Author) 115 refs.

  14. Performance of a prototype water Cherenkov detector for LHAASO project

    International Nuclear Information System (INIS)

    An, Q.; Bai, Y.X.; Bi, X.J.; Cao, Z.; Cao, Zhe; Chang, J.F.; Chen, G.; Chen, L.H.; Chen, M.J.; Chen, T.L.; Chen, Y.T.; Cui, S.W.; Dai, B.Z.; Danzengluobu; Feng, C.F.; Gao, B.; Gu, M.H.; Hao, X.J.; He, H.H.; Hu, H.B.

    2011-01-01

    A large high-altitude air shower observatory is to be built at Yang-Ba-Jing, Tibet, China. One of its main purposes is to survey the northern sky for very-high-energy (above 100 GeV) gamma ray sources via its ground-based water Cherenkov detector array. To gain full knowledge of water Cherenkov technique in detecting air showers, a prototype water Cherenkov detector is built at the Institute of High Energy Physics, Beijing. The performance of the prototype water Cherenkov detector is studied by measuring its response to cosmic muons. The results are compared with those from a full Monte Carlo simulation to provide a series of information regarding the prototype detector in guiding electronics design and detector optimization.

  15. CVD diamond based soft X-ray detector with fast response

    International Nuclear Information System (INIS)

    Li Fang; Hou Lifei; Su Chunxiao; Yang Guohong; Liu Shenye

    2010-01-01

    A soft X-ray detector has been made with high quality chemical vapor deposited (CVD) diamond and the electrical structure of micro-strip. Through the measurement of response time on a laser with the pulse width of 10 ps, the full width at half maximum of the data got in the oscilloscope was 115 ps. The rise time of the CVD diamond detector was calculated to be 49 ps. In the experiment on the laser prototype facility, the signal got by the CVD diamond detector was compared with that got by a soft X-ray spectrometer. Both signals coincided well. The detector is proved to be a kind of reliable soft X-ray detector with fast response and high signal-to-noise ratio. (authors)

  16. The International Large Detector: Letter of Intent

    CERN Document Server

    Abe, Toshinori; Abramowicz, Halina; Adamus, Marek; Adeva, Bernardo; Afanaciev, Konstantin; Aguilar-Saavedra, Juan Antonio; Alabau Pons, Carmen; Albrecht, Hartwig; Andricek, Ladislav; Anduze, Marc; Aplin, Steve J.; Arai, Yasuo; Asano, Masaki; Attie, David; Attree, Derek J.; Burger, Jochen; Bailey, David; Balbuena, Juan Pablo; Ball, Markus; Ballin, James; Barbi, Mauricio; Barlow, Roger; Bartels, Christoph; Bartsch, Valeria; Bassignana, Daniela; Bates, Richard; Baudot, Jerome; Bechtle, Philip; Beck, Jeannine; Beckmann, Moritz; Bedjidian, Marc; Behnke, Ties; Belkadhi, Khaled; Bellerive, Alain; Bentvelsen, Stan; Bergauer, Thomas; Berggren, C.Mikael U.; Bergholz, Matthias; Bernreuther, Werner; Besancon, Marc; Besson, Auguste; Bhattacharya, Sudeb; Bhuyan, Bipul; Biebel, Otmar; Bilki, Burak; Blair, Grahame; Blumlein, Johannes; Bo, Li; Boisvert, Veronique; Bondar, A.; Bonvicini, Giovanni; Boos, Eduard; Boudry, Vincent; Bouquet, Bernard; Bouvier, Joel; Bozovic-Jelisavcic, Ivanka; Brient, Jean-Claude; Brock, Ian; Brogna, Andrea; Buchholz, Peter; Buesser, Karsten; Bulgheroni, Antonio; Butler, John; Buttar, Craig; Buzulutskov, A.F.; Caccia, Massimo; Caiazza, Stefano; Calcaterra, Alessandro; Caldwell, Allen; Callier, Stephane L.C.; Calvo Alamillo, Enrique; Campbell, Michael; Campbell, Alan J.; Cappellini, Chiara; Carloganu, Cristina; Castro, Nuno; Castro Carballo, Maria Elena; Chadeeva, Marina; Chakraborty, Dhiman; Chang, Paoti; Charpy, Alexandre; Chen, Xun; Chen, Shaomin; Chen, Hongfang; Cheon, Byunggu; Choi, Suyong; Choudhary, B.C.; Christen, Sandra; Ciborowski, Jacek; Ciobanu, Catalin; Claus, Gilles; Clerc, Catherine; Coca, Cornelia; Colas, Paul; Colijn, Auke; Colledani, Claude; Combaret, Christophe; Cornat, Remi; Cornebise, Patrick; Corriveau, Francois; Cvach, Jaroslav; Czakon, Michal; D'Ascenzo, Nicola; Da Silva, Wilfrid; Dadoun, Olivier; Dam, Mogens; Damerell, Chris; Danilov, Mikhail; Daniluk, Witold; Daubard, Guillaume; David, Dorte; David, Jacques; De Boer, Wim; De Groot, Nicolo; De Jong, Sijbrand; De Jong, Paul; De La Taille, Christophe; De Masi, Rita; De Roeck, Albert; Decotigny, David; Dehmelt, Klaus; Delagnes, Eric; Deng, Zhi; Desch, Klaus; Dieguez, Angel; Diener, Ralf; Dima, Mihai-Octavian; Dissertori, Gunther; Dixit, Madhu S.; Dolezal, Zdenek; Dolgoshein, Boris A.; Dollan, Ralph; Dorokhov, Andrei; Doublet, Philippe; Doyle, Tony; Doziere, Guy; Dragicevic, Marko; Drasal, Zbynek; Drugakov, Vladimir; Duarte Campderros, Jordi; Dulucq, Frederic; Dumitru, Laurentiu Alexandru; Dzahini, Daniel; Eberl, Helmut; Eckerlin, Guenter; Ehrenfeld, Wolfgang; Eigen, Gerald; Eklund, Lars; Elsen, Eckhard; Elsener, Konrad; Emeliantchik, Igor; Engels, Jan; Evrard, Christophe; Fabbri, Riccardo; Faber, Gerard; Faucci Giannelli, Michele; Faus-Golfe, Angeles; Feege, Nils; Feng, Cunfeng; Ferencei, Jozef; Fernandez Garcia, Marcos; Filthaut, Frank; Fleck, Ivor; Fleischer, Manfred; Fleta, Celeste; Fleury, Julien L.; Fontaine, Jean-Charles; Foster, Brian; Fourches, Nicolas; Fouz, Mary-Cruz; Frank, Sebastian; Frey, Ariane; Frotin, Mickael; Fujii, Hirofumi; Fujii, Keisuke; Fujimoto, Junpei; Fujita, Yowichi; Fusayasu, Takahiro; Fuster, Juan; Gaddi, Andrea; Gaede, Frank; Galkin, Alexei; Galkin, Valery; Gallas, Abraham; Gallin-Martel, Laurent; Gamba, Diego; Gao, Yuanning; Garrido Beltran, Lluis; Garutti, Erika; Gastaldi, Franck; Gaur, Bakul; Gay, Pascal; Gellrich, Andreas; Genat, Jean-Francois; Gentile, Simonetta; Gerwig, Hubert; Gibbons, Lawrence; Ginina, Elena; Giraud, Julien; Giraudo, Giuseppe; Gladilin, Leonid; Goldstein, Joel; Gonzalez Sanchez, Francisco Javier; Gournaris, Filimon; Greenshaw, Tim; Greenwood, Z.D.; Grefe, Christian; Gregor, Ingrid-Maria; Grenier, Gerald Jean; Gris, Philippe; Grondin, Denis; Grunewald, Martin; Grzelak, Grzegorz; Gurtu, Atul; Haas, Tobias; Haensel, Stephan; Hajdu, Csaba; Hallermann, Lea; Han, Liang; Hansen, Peter H.; Hara, Takanori; Harder, Kristian; Hartin, Anthony; Haruyama, Tomiyoshi; Harz, Martin; Hasegawa, Yoji; Hauschild, Michael; He, Qing; Hedberg, Vincent; Hedin, David; Heinze, Isa; Helebrant, Christian; Henschel, Hans; Hensel, Carsten; Hertenberger, Ralf; Herve, Alain; Higuchi, Takeo; Himmi, Abdelkader; Hironori, Kazurayama; Hlucha, Hana; Hommels, Bart; Horii, Yasuyuki; Horvath, Dezso; Hostachy, Jean-Yves; Hou, Wei-Shu; Hu-Guo, Christine; Huang, Xingtao; Huppert, Jean Francois; Ide, Yasuhiro; Idzik, Marek; Iglesias Escudero, Carmen; Ignatenko, Alexandr; Igonkina, Olga; Ikeda, Hirokazu; Ikematsu, Katsumasa; Ikemoto, Yukiko; Ikuno, Toshinori; Imbault, Didier; Imhof, Andreas; Imhoff, Marc; Ingbir, Ronen; Inoue, Eiji; Ioannis, Giomataris; Ishikawa, Akimasa; Itagaki, Kennosuke; Ito, Kazutoshi; Itoh, Hideo; Iwabuchi, Masaya; Iwai, Go; Iwamoto, Toshiyuki; Jacosalem, Editha P.; Jaramillo Echeverria, Richard; Jeans, Daniel T D.; Jing, Fanfan; Jing, Ge; Jokic, Stevan; Jonsson, Leif; Jore, Matthieu; Jovin, Tatjana; Kafer, Daniela; Kajino, Fumiyoshi; Kamai, Yusuke; Kaminski, Jochen; Kamiya, Yoshio; Kaplan, Alexander; Kapusta, Frederic; Kar, Deepak; Karlen, Dean; Katayama, Nobu; Kato, Eriko; Kato, Yukihiro; Kaukher, Alexander; Kawagoe, Kiyotomo; Kawahara, Hiroki; Kawai, Masanori; Kawasaki, Takeo; Khan, Sameen Ahmed; Kieffer, Robert; Kielar, Eryk; Kiesenhofer, Wolfgang; Kiesling, Christian M.; Killenberg, Martin; Kim, Donghee; Kim, Choong Sun; Kim, Guinyun; Kim, Hong Joo; Kim, Eun-Joo; Kim, Hyunok; Kim, Shinhong; Kircher, Francois; Kisielewska, Danuta; Kleinwort, Claus; Klimkovich, Tatsiana; Kluge, Hanna; Kluit, Peter Martin; Kobayashi, Makoto; Kobel, Michael; Kodama, Hideyo; Kodys, Peter; Koetz, U.; Koffeman, Els; Kohriki, Takashi; Komamiya, Sachio; Kondou, Yoshinari; Korbel, Volker; Kotera, Katsushige; Krucker, Dirk; Kraml, Sabine; Krammer, Manfred; Krastev, Kaloyan; Krause, Bernward; Krautscheid, Thorsten; Kschioneck, Kirsten; Kuang, Yu-Ping; Kuhlmann, Jan; Kuroiwa, Hirotoshi; Kusano, Tomonori; Kvasnicka, Peter; Lacasta Llacer, Carlos; Lagorio, Eric; Laktineh, Imad; Lange, Wolfgang; Lebrun, Patrice; Lee, Jik; Lehner, Frank; Lesiak, Tadeusz; Levy, Aharon; Li, Bo; Li, Ting; Li, Yulan; Li, Hengne; Liang, Zuotang; Lima, Guilherme; Linde, Frank; Linssen, Lucie; Linzmaier, Diana; List, Benno; List, Jenny; Liu, Bo; Llopart Cudie, Xavier; Lohmann, Wolfgang; Lopez Virto, Amparo; Lozano, Manuel; Lu, Shaojun; Lucaci-Timoce, Angela Isabela; Lumb, Nick; Lundberg, Bjorn; Lutz, Pierre; Lutz, Benjamin; Lux, Thorsten; Luzniak, Pawel; Lyapin, Alexey; Ma, Wengan; Maczewski, Lukasz; Mader, Wolfgang F.; Maity, Manas; Majumdar, Nayana; Majumder, Gobinda; Maki, Akihiro; Makida, Yasuhiro; Mamuzic, Judita; Marc, Dhellot; Marchesini, Ivan; Marcisovsky, Michal; Marias, Carlos; Marshall, John; Martens, Cornelius; Martin, Victoria J.; Martin, Jean-Pierre; Martin-Chassard, Gisele; Martinez Rivero, Celso; Martyn, Hans-Ulrich; Mathez, Herve; Mathieu, Antoine; Matsuda, Takeshi; Matsunaga, Hiroyuki; Matsushita, Takashi; Mavromanolakis, Georgios; Mcdonald, Kirk T.; Mereu, Paolo; Merk, Marcel; Merkin, Mikhail M.; Meyer, Niels; Meyners, Norbert; Mihara, Satoshi; Miller, David J.; Miller, Owen; Mitaroff, Winfried A.; Miyamoto, Akiya; Miyata, Hitoshi; Mjornmark, Ulf; Mnich, Joachim; Monig, Klaus; Moll, Andreas; Moortgat-Pick, Gudrid A.; Mora De Freitas, Paulo; Morel, Frederic; Moretti, Stefano; Morgunov, Vasily; Mori, Toshinori; Mori, Takashi; Morin, Laurent; Morozov, Sergey; Moser, Hans-Gunther; Moser, Fabian; Moya, David; Mudrinic, Mihajlo; Mukhopadhyay, Supratik; Murakami, Takeshi; Musa, Luciano; Musat, Gabriel; Nagamine, Tadashi; Nakamura, Isamu; Nakano, Eiichi; Nakashima, Kenichi; Nakayoshi, Kazuo; Nakazawa, Hideyuki; Nam, Shinwoo; Nam, Jiwoo; Nemecek, Stanislav; Niebuhr, Carsten; Niechciol, Marcus; Niezurawski, Piotr; Nishida, Shohei; Nishiyama, Miho; Nitoh, Osamu; Norbeck, Ed; Nozaki, Mitsuaki; O'Shea, Val; Ohlerich, Martin; Okada, Nobuchika; Olchevski, Alexander; Olivier, Bob; Oliwa, Krzysztof; Omori, Tsunehiko; Onel, Yasar; Ono, Hiroaki; Ono, Yoshimasa; Onuki, Yoshiyuki; Ootani, Wataru; Orava, Risto; Orlandea, Marius Ciprian; 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Sudo, Yuji; Suehara, Taikan; Suekane, Fumihiko; Suetsugu, Yusuke; Sugimoto, Yasuhiro; Sugiyama, Akira; Sumisawa, Kazutaka; Suzuki, Shiro; Swientek, Krzysztof; Tabassam, Hajrah; Takahashi, Tohru; Takeda, Hiroshi; Takeshita, Tohru; Takubo, Yosuke; Tanabe, Tomohiko; Tanaka, Shuji; Tanaka, Ken-Ichi; Tanaka, Manobu; Tapprogge, Stefan; Tarkovsky, Evgueny I.; Tauchi, Toshiaki; Tauchi, Kazuya; Telnov, Valery I.; Teodorescu, Eliza; Thomson, Mark; Tian, Junping; Timmermans, Jan; Titov, Maxim P.; Tokushuku, Katsuo; Tozuka, Shunsuke; Tsuboyama, Toru; Ueno, Koji; Ullan, Miguel; Uozumi, Satoru; Urakawa, Junji; Ushakov, Andriy; Ushiroda, Yutaka; Valentan, Manfred; Valin, Isabelle; Van Der Graaf, Harry; Van Doren, Brian; Van Kooten, Rick J.; Vander Donckt, Muriel; Vanel, Jean-Charles; Vazquez Regueiro, Pablo; Verzocchi, Marco; Vescovi, Christophe; Videau, Henri L.; Vila, Ivan; Vilasis-Cardona, Xavier; Vogel, Adrian; Volkenborn, Robert; Vos, Marcel; Voutsinas, Yorgos; Vrba, Vaclav; Vreeswijk, Marcel; Walsh, Roberval; Waltenberger, Wolfgang; Wang, Min-Zu; Wang, Yi; Wang, Xiaoliang; Wang, Qun; Wang, Meng; Ward, David R.; Warren, Matthew; Watanabe, Minori; Watanabe, Takashi; Watson, Nigel K.; Wattimena, Nanda; Wendt, Oliver; Wermes, Norbert; Weuste, Lars; Wichmann, Katarzyna; Wienemann, Peter; Wierba, Wojciech; Wilson, Graham W.; Wilson, John A.; Wing, Matthew; Winter, Marc; Wobisch, Markus; Worek, Malgorzata; Xella, Stefania; Xu, Zizong; Yamaguchi, Akira; Yamaguchi, Hiroshi; Yamamoto, Hitoshi; Yamaoka, Hiroshi; Yamashita, Satoru; Yamauchi, M.; Yamazaki, Yuji; Yamouni, Mahfoud; Yan, Wenbiao; Yanagida, Koji; Yang, Haijun; Yang, Jongmann; Yang, Jin Min; Yang, Zhenwei; Yasu, Yoshiji; Yonamine, Ryo; Yoshida, Kohei; Yoshida, Takuo; Yoshioka, Tamaki; Yu, Chunxu; Yu, Intae; Yue, Qian; Zacek, Josef; Zalesak, Jaroslav; Zarnecki, Aleksander Filip; Zawiejski, Leszek; Zeitnitz, Christian; Zerwas, Dirk; Zeuner, Wolfram; Zhang, Yanxi; Zhang, Ziping; Zhang, Renyou; Zhang, Xueyao; Zhang, Zhiqing; Zhao, Jiawei; Zhao, Zhengguo; Zheng, Baojun; Zhong, Liang; Zhou, Yongzhao; Zhu, Xianglei; Zhu, Chengguang; Zomer, Fabian; Zutshi, Vishnu

    2010-01-01

    The International Large Detector (ILD) is a concept for a detector at the International Linear Collider, ILC. The ILC will collide electrons and positrons at energies of initially 500 GeV, upgradeable to 1 TeV. The ILC has an ambitious physics program, which will extend and complement that of the Large Hadron Collider (LHC). A hallmark of physics at the ILC is precision. The clean initial state and the comparatively benign environment of a lepton collider are ideally suited to high precision measurements. To take full advantage of the physics potential of ILC places great demands on the detector performance. The design of ILD is driven by these requirements. Excellent calorimetry and tracking are combined to obtain the best possible overall event reconstruction, including the capability to reconstruct individual particles within jets for particle ow calorimetry. This requires excellent spatial resolution for all detector systems. A highly granular calorimeter system is combined with a central tracker which st...

  17. Sample Selection for Training Cascade Detectors.

    Science.gov (United States)

    Vállez, Noelia; Deniz, Oscar; Bueno, Gloria

    2015-01-01

    Automatic detection systems usually require large and representative training datasets in order to obtain good detection and false positive rates. Training datasets are such that the positive set has few samples and/or the negative set should represent anything except the object of interest. In this respect, the negative set typically contains orders of magnitude more images than the positive set. However, imbalanced training databases lead to biased classifiers. In this paper, we focus our attention on a negative sample selection method to properly balance the training data for cascade detectors. The method is based on the selection of the most informative false positive samples generated in one stage to feed the next stage. The results show that the proposed cascade detector with sample selection obtains on average better partial AUC and smaller standard deviation than the other compared cascade detectors.

  18. Comparison of gamma densitometer detectors used in loss of coolant studies

    International Nuclear Information System (INIS)

    Shipp, R.L.

    1979-01-01

    Ionization chamber type gamma detectors are used in water-steam density measurements in loss of coolant studies at Oak Ridge National Laboratory. Ionization chambers have replaced current-mode scintillation detectors to obtain stability and freedom from magnetic field interference. However, this change results in some loss of fast transient response. Results of studies comparing the transient response of ionization chamber detectors, plastic scintillation detectors, and sodium iodide (NaI) detectors to rapid changes in gamma intensity demonstrate that plastic scintillation detectors have the fastest response and most closely reproduce the transient; ionization chambers have an initial fast response followed by a slower response, which may produce errors in fast transient measurements; and NaI scintillation detectors have a moderately fast initial response followed by an extremely slow response, which produces errors in even slow transient measurements

  19. A twin sibling with Prader-Willi syndrome caused by type 2 microdeletion following assisted reproductive technology: A case report.

    Science.gov (United States)

    Han, Ji Yoon; Park, Joonhong; Jang, Woori; Chae, Hyojin; Kim, Myungshin; Kim, Yonggoo

    2016-07-01

    Prader-Willi syndrome (PWS) is a neurobehavioral imprinting disorder, which arises due to an absence of paternally expressed genes within the 15q11.2-q13 region. This occurs via one of the three main genetic mechanisms, as follows: Deletion of the paternally inherited 15q11.2-q13 region, maternal uniparental disomy and imprinting defect. Recent studies have reported an association between imprinting disorders and assisted reproductive technologies (ART). The current study presents a 6-year-old female patient who is a dizygotic twin, in which one was born with de novo microdeletion at 15q11.2-q13.1 following in vitro fertilization. The patient had characteristic facial features including narrow bifrontal diameter, strabismus, downturned mouth, feeding problems and generalized hypotonia during infancy, developmental delay, mental retardation and rapid weight gain. Based upon phenotypic resemblance and the medical records, methylation-specific multiplex ligation-dependent probe amplification and array-based comparative genome hybridization analyses demonstrate type 2 microdeletion between breaking point 2 (BP2) and BP3, which occur from MKRN3 through HERC2 at 15q11.2-q13.1. To the best of our knowledge, the present study is the first to report a PWS case born following ART reported in South Korea. In addition to previous studies, the present study contributes to the consensus regarding genotype-phenotype comparisons in this respect.

  20. Antioxidant Effects of Potassium Ascorbate with Ribose Therapy in a Case with Prader Willi Syndrome

    Directory of Open Access Journals (Sweden)

    C. Anichini

    2012-01-01

    Full Text Available Oxidative stress (OS is involved in several human diseases, including obesity, diabetes, atherosclerosis, carcinogenesis, as well as genetic diseases. We previously found that OS occurs in Down Syndrome as well as in Beckwith-Wiedemann Syndrome (BWS. Here we describe the clinical case of a female patient with Prader Willi Syndrome (PWS, a genomic imprinting disorder, characterized by obesity, atherosclerosis and diabetes mellitus type 2, pathologies in which a continuous and important production of free radicals takes place. We verified the presence of OS by measuring a redox biomarkers profile including total hydroperoxides (TH, non protein-bound iron (NPBI, thiols (SH, advanced oxidation protein products (AOPP and isoprostanes (IPs. Thus we introduced in therapy an antioxidant agent, namely potassium ascorbate with ribose (PAR, in addition to GH therapy and we monitored the redox biomarkers profile for four years. A progressive decrease in OS biomarkers occurred until their normalization. In the meantime a weight loss was observed together with a steady growth in standards for age and sex.