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  1. Hutchinson-Gilford Progeria Syndrome

    National Research Council Canada - National Science Library

    Gopal G; Belavadi GB

    2014-01-01

    Hutchinson-Gilford Progeria syndrome (HGPS) is a rare pediatric genetic syndrome associated with a characteristic aged appearance very early in life, generally leading to death in the second decade of life...

  2. Genetics Home Reference: Hutchinson-Gilford progeria syndrome

    Science.gov (United States)

    ... Health Conditions Hutchinson-Gilford progeria syndrome Hutchinson-Gilford progeria syndrome Enable Javascript to view the expand/collapse ... PDF Open All Close All Description Hutchinson-Gilford progeria syndrome is a genetic condition characterized by the ...

  3. Hutchinson-Gilford progeria syndrome

    OpenAIRE

    Amar Singh Bhukya; Bellum Siva Nagi Reddy

    2015-01-01

    Hutchinson-Gilford Progeria syndrome (HGPS) is a rare pediatric genetic syndrome associated with a characteristic aged appearance very early in life, generally leading to death in the second decade of life. Apart from premature aging, the other notable characteristics of children with HGPS include extreme short stature, prominent superficial veins, poor weight gain, alopecia, as well as various skeletal and cardiovascular pathologies associated with advanced age. The pattern of inheritance of...

  4. Hutchinson-Gilford progeria syndrome

    Directory of Open Access Journals (Sweden)

    Zahoor Hussain Daraz

    2017-06-01

    Full Text Available Hutchinson-Gilford progeria syndrome (HGPS is a rare genetic disease in which symptoms of aging are manifested at an early age. In the present report, we describe a 9 months old female child presented with a history of progressive coarsening of skin, failure to thrive and irregular bumps over thighs, buttocks and lower limbs for the last 7½ months. In the course of time, she developed alopecia, hyperpigmented spots over the abdomen with thickening and a typical facial profile of HGPS including micrognathia, absent ear lobules, prominent eyes, loss of eyelashes, eyebrows and a bluish hue over the nose.

  5. Hutchinson-Gilford Progeria Syndrome

    Directory of Open Access Journals (Sweden)

    Gopal G

    2014-08-01

    Full Text Available Hutchinson-Gilford Progeria syndrome (HGPS is a rare pediatric genetic syndrome associated with a characteristic aged appearance very early in life, generally leading to death in the second decade of life. Apart from premature aging, the other notable characteristics of children with HGPS include extreme short stature, prominent superficial veins, poor weight gain, alopecia, as well as various skeletal and cardiovascular pathologies associated with advanced age. The pattern of inheritance of HGPS is uncertain, though both autosomal dominant and autosomal recessive modes have been described. Recent genetic studies have demonstrated mutations in the LMNA gene in children with HGPS. In this article, we report a 16 years old girl who had the phenotypic features of HGPS and was later confirmed to have LMNA mutation by genetic analysis.

  6. Virginia Tech's Cook Counseling Center receives international counseling accreditation

    OpenAIRE

    DeLauder, Rachel

    2010-01-01

    The Virginia Tech Thomas E. Cook Counseling Center has been accredited by the International Association of Counseling Services, Inc., an organization of United States, Canadian, and Australian counseling agencies based in Alexandria, Va.

  7. Hutchinson-Gilford progeria syndrome.

    Science.gov (United States)

    Ullrich, Nicole J; Gordon, Leslie B

    2015-01-01

    Hutchinson-Gilford progeria syndrome (HGPS) is an extremely rare, uniformly fatal, segmental "premature aging" disease in which children exhibit phenotypes that may give us insights into the aging process at both the cellular and organismal levels. Initial presentation in early childhood is primarily based on growth and dermatologic findings. Primary morbidity and mortality for children with HGPS is from atherosclerotic cardiovascular disease and strokes with death occurring at an average age of 14.6 years. There is increasing data to support a unique phenotype of the craniofacial and cerebrovascular anatomy that accompanies the premature aging process. Strokes in HGPS can occur downstream of carotid artery and/or vertebral artery occlusion, stenosis, and calcification, with prominent collateral vessel formation. Both large and small vessel disease are present, and strokes are often clinically silent. Despite the presence of multisystem premature aging, children with HGPS do not appear to have cognitive deterioration, suggesting that some aspects of brain function may be protected from the deleterious effects of progerin, the disease-causing protein. Based on limited autopsy material, there is no pathologic evidence of dementia or Alzheimer-type changes. In a transgenic mouse model of progeria with expression of the most common HGPS mutation in brain, skin, bone, and heart, there are distortions of neuronal nuclei at the ultrastructural level with irregular shape and severe invaginations, but no evidence of inclusions or aberrant tau in brain sections. Importantly, the nuclear distortions did not result in significant changes in gene expression in hippocampal neurons. This chapter will discuss both preclinical and clinical aspects of the genetics, pathobiology, clinical phenotype, clinical care, and treatment of HGPS, with special attention toward neurologic and cutaneous findings.

  8. 34 CFR 656.4 - What types of Centers receive grants?

    Science.gov (United States)

    2010-07-01

    ... the country or area; or (2) International studies or the international aspects of contemporary issues or topics (such as international business or energy) while providing instruction in modern foreign... STUDIES OR FOREIGN LANGUAGE AND INTERNATIONAL STUDIES General § 656.4 What types of Centers receive...

  9. Geodetic Control Points, Hutchinson, KS Benchmarks created by city surveyor at that time, Published in 1980, City of Hutchinson.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Geodetic Control Points dataset, was produced all or in part from Field Survey/GPS information as of 1980. It is described as 'Hutchinson, KS Benchmarks created...

  10. Initial cutaneous manifestations of Hutchinson-Gilford progeria syndrome.

    Science.gov (United States)

    Rork, Jillian F; Huang, Jennifer T; Gordon, Leslie B; Kleinman, Monica; Kieran, Mark W; Liang, Marilyn G

    2014-01-01

    Hutchinson-Gilford progeria syndrome (HGPS) is a rare, uniformly fatal, premature aging disease with distinct dermatologic features. We sought to identify and describe the initial skin and hair findings as potential diagnostic signs of the disease. We performed a chart review of the structured initial intake histories of 39 individuals with HGPS enrolled in clinical trials from 2007 to 2010 at Boston Children's Hospital, limited to cutaneous history from birth to 24 months. Medical photographs were provided through the clinical trials and the Progeria Research Foundation Medical and Research Database at Brown University Center for Gerontology and Healthcare Research. All 39 patients reported skin and hair abnormalities within the first 24 months of life. Pathologies included sclerodermoid change, prominent superficial veins, dyspigmentation, and alopecia. The mean age of presentation for each finding was <12 months. The most frequently reported skin feature was sclerodermoid change, which commonly involved the abdomen and bilateral lower extremities. Prominent superficial vasculature manifested as circumoral cyanosis and pronounced veins on the scalp and body. Hypo- and hyperpigmentation were observed over areas of sclerodermoid change. Scalp alopecia progressed in a distinct pattern, with preservation of the hair over the midscalp and vertex areas for the longest period of time. HGPS has distinct cutaneous manifestations during the first 2 years of life that may be the first signs of disease. Awareness of these findings could expedite diagnosis.

  11. Diamond Radio Receiver: Nitrogen-Vacancy Centers as Fluorescent Transducers of Microwave Signals

    Science.gov (United States)

    Shao, Linbo; Zhang, Mian; Markham, Matthew; Edmonds, Andrew M.; Lončar, Marko

    2016-12-01

    We demonstrate a robust frequency-modulated radio receiver using electron-spin-dependent photoluminescence of nitrogen-vacancy centers in diamond. The carrier frequency of the frequency-modulated signal is in the 2.8-GHz range, determined by the zero-field splitting in the nitrogen-vacancy electronic ground state. The radio can be tuned over 300 MHz by applying an external dc magnetic field. We show the transmission of high-fidelity audio signals over a bandwidth of 91 kHz using the diamond radio. We demonstrate operating temperature of the radio as high as 350 ° C .

  12. Spaceborne GPS receiver antenna phase center offset and variation estimation for the Shiyan 3 satellite

    Directory of Open Access Journals (Sweden)

    Gu Defeng

    2016-10-01

    Full Text Available In determining the orbits of low Earth orbit (LEO satellites using spaceborne GPS, the errors caused by receiver antenna phase center offset (PCO and phase center variations (PCVs are gradually becoming a major limiting factor for continued improvements to accuracy. Shiyan 3, a small satellite mission for space technology experimentation and climate exploration, was developed by China and launched on November 5, 2008. The dual-frequency GPS receiver payload delivers 1 Hz data and provides the basis for precise orbit determination within the range of a few centimeters. The antenna PCO and PCV error characteristics and the principles influencing orbit determination are analyzed. The feasibility of PCO and PCV estimation and compensation in different directions is demonstrated through simulation and in-flight tests. The values of receiver antenna PCO and PCVs for Gravity Recovery and Climate Experiment (GRACE and Shiyan 3 satellites are estimated from one month of data. A large and stable antenna PCO error, reaching up to 10.34 cm in the z-direction, is found with the Shiyan 3 satellite. The PCVs on the Shiyan 3 satellite are estimated and reach up to 3.0 cm, which is slightly larger than that of GRACE satellites. Orbit validation clearly improved with independent k-band ranging (KBR and satellite laser ranging (SLR measurements. For GRACE satellites, the average root mean square (RMS of KBR residuals improved from 1.01 cm to 0.88 cm. For the Shiyan 3 satellite, the average RMS of SLR residuals improved from 4.95 cm to 4.06 cm.

  13. Spaceborne GPS receiver antenna phase center offset and variation estimation for the Shiyan 3 satellite

    Institute of Scientific and Technical Information of China (English)

    Gu Defeng; Lai Yuwang; Liu Junhong; Ju Bing; Tu Jia

    2016-01-01

    In determining the orbits of low Earth orbit (LEO) satellites using spaceborne GPS, the errors caused by receiver antenna phase center offset (PCO) and phase center variations (PCVs) are gradually becoming a major limiting factor for continued improvements to accuracy. Shiyan 3, a small satellite mission for space technology experimentation and climate exploration, was developed by China and launched on November 5, 2008. The dual-frequency GPS receiver payload delivers 1 Hz data and provides the basis for precise orbit determination within the range of a few centime-ters. The antenna PCO and PCV error characteristics and the principles influencing orbit determi-nation are analyzed. The feasibility of PCO and PCV estimation and compensation in different directions is demonstrated through simulation and in-flight tests. The values of receiver antenna PCO and PCVs for Gravity Recovery and Climate Experiment (GRACE) and Shiyan 3 satellites are estimated from one month of data. A large and stable antenna PCO error, reaching up to 10.34 cm in the z-direction, is found with the Shiyan 3 satellite. The PCVs on the Shiyan 3 satellite are estimated and reach up to 3.0 cm, which is slightly larger than that of GRACE satellites. Orbit validation clearly improved with independent k-band ranging (KBR) and satellite laser ranging (SLR) measurements. For GRACE satellites, the average root mean square (RMS) of KBR resid-uals improved from 1.01 cm to 0.88 cm. For the Shiyan 3 satellite, the average RMS of SLR resid-uals improved from 4.95 cm to 4.06 cm.

  14. Otologic and Audiologic Manifestations of Hutchinson-Gilford Progeria Syndrome

    Science.gov (United States)

    Guardiani, Elizabeth; Zalewski, Christopher; Brewer, Carmen; Merideth, Melissa; Introne, Wendy; Smith, Ann C.M; Gordon, Leslie; Gahl, William; Kim, H. Jeffrey

    2013-01-01

    Objectives To define the audiologic and otologic phenotype of Hutchinson-Gilford Progeria syndrome (HGPS). Study Design Prospective case series. Methods Fifteen patients with HGPS were enrolled in a prospective natural history study; fourteen were evaluated in the neurotology clinic and eleven received audiologic evaluations. The physical exam and audiologic findings of these patients were reviewed to define an otologic and audiologic phenotype for HGPS in the largest series of subjects in the literature. Results All patients were noted to have stiff auricular cartilages, small or absent lobules and hypoplasia of the lateral soft tissue portion of the external ear canal leading to a shortened canal. Ten of 14 patients (71%) had dry cerumen impaction and four of 14 patients (29%) reported a history of recurrent otitis media. Nineteen of 22 ears (86.4%) demonstrated low frequency conductive hearing loss in the 250 Hz to 500 Hz range. Sixteen of 22 ears (73%) had type A tympanograms; three of 22 ears (14%) displayed bimodal or "W" peaked tympanograms; two of 22 ears (9%) had type B tympanograms; one of 22 ears (4%) had a type C tympanogram. Nine of 10 patients had distortion product otoacoustic emissions consistent with normal peripheral hearing sensitivity. Conclusions HGPS is caused by a mutation in the LMNA gene resulting in the production of an abnormal nuclear protein; this in turn affects nuclear structure and function. Patients with HGPS have characteristic otologic features due to cartilaginous and subcutaneous tissue abnormalities and typically demonstrate low frequency conductive hearing loss despite largely normal tympanometry. It is important to be aware of these conditions in managing these patients. PMID:21898437

  15. Hutchinson-Gilford progeria syndrome: a rare case report

    Directory of Open Access Journals (Sweden)

    Kalegowda Deepadarshan

    2016-04-01

    Full Text Available Progeroid syndromes are characterised by clinical features of physiological aging at an early age. Hutchinson-Gilford progeria syndrome is a type of progeroid syndrome, characterised by abnormal facies, bone abnormalities, sclerodermatous skin changes and retarded physical development. Average life expectancy of progeria patients is 13 years. Herein we are reporting a case of progeria who is 21 years old.

  16. Impact of varied center volume categories on volume-outcome relationship in children receiving ECMO for heart operations.

    Science.gov (United States)

    Rettiganti, Mallikarjuna; Seib, Paul M; Robertson, Michael J; Wilcox, Andrew; Gupta, Punkaj

    2016-09-01

    To study the volume-outcome relationship among children receiving extracorporeal membrane oxygenation (ECMO), different studies from different databases use different volume categories. The objective of this study was to evaluate if different center volume categories impact the volume-outcome relationship among children receiving ECMO for heart operations. We performed a post hoc analysis of data from an existing national database, the Pediatric Health Information System. Centers were classified into five different volume categories using different cut-offs and different variables. Mortality rates were compared between the varied volume categories using a mixed effects logistic regression model after adjusting for patient- and center-level risk factors. Data collection included demographic information, baseline characteristics, pre-ECMO risk factors, operation details, patient diagnoses, and center data. In unadjusted analysis, there was a significant relationship between center volume and mortality, with low-and medium-volume centers associated with higher mortality rates compared to high-volume centers in all volume categories, except the hierarchical clustering volume category. In contrast, there was no significant association between center-volume and mortality among all volume categories in adjusted analysis. We concluded that high-volume centers were not associated with improved outcomes for the majority of the categorization schemes despite using different cut-offs and different variables for volume categorization.

  17. Hutchinson-Gilford progeria syndrome%Hutchinson-Gilford早老综合征

    Institute of Scientific and Technical Information of China (English)

    张韡; 苏忠兰; 吴侃; 宋昊; 温斯健; 杨莹; 刘白; 林志淼; 孙建方

    2016-01-01

    To report a case of Hutchinson-Gilford progeria syndrome (HGPS).Peripheral blood samples were collected from a 5-year-old boy with HGPS and his parents.DNA was extracted from these samples,and PCR was performed to amplify exon 11 of the LMNA gene and its flanking sequences followed by DNA sequencing.The patient presented with scleroderma-like skin changes all over the body,growth retardation,distinctive facial features and hypotrichosis.His hip and knee joints could not be straightened completely,giving a horse-riding stance.A heterozygous mutation C.1824C > T was identified in exon 11 of the LMNA gene in the patient but not in either of his parents.A retrospective analysis was carried out on 18 Chinese patients with genetically diagnosed HPGS.Of them,9 classical cases were all sporadic with a heterozygous mutation of C.1824C>T.None of the patients with classical HPGS showed abnormality at birth,but all of them developed symptoms within 1 year after birth.Boys were more frequent to be affected by classical HPGS than girls,with the male/female ratio being 2:1.There was a familial tendency for the occurrence of atypical HPGS,and boys and girls appeared to be affected by HPGS at a similar probability.Three families with atypical HPGS all showed a homozygous LMNA mutation c.1579C>T.%报告1例Hutchinson-Gilford早老综合征(HGPS).对1例患儿及其父母外周血LMNA基因11号外显子和侧翼序列进行测序.患者男,5岁,全身皮肤呈硬皮病样改变,生长迟滞,特殊面容,毛发稀少.髋、膝关节均不能完全伸直,呈“骑马样站姿”.患儿LMNA基因11号外显子c.1824C>T杂合点突变,父母均未检测到该位点突变.文中还通过回顾性分析,探讨中国人群中通过基因学诊断的18例病例的疾病特点.我国基因学诊断的18例HGPS中,9例经典型HGPS均为散发病例,基因表型均上出现c.1824C>T杂合突变.患儿均在1岁以内发病,出生时基本未表现出“异常”.

  18. Advanced postbuckling and imperfection sensitivity of the elastic-plastic Shanley-Hutchinson model column

    DEFF Research Database (Denmark)

    Christensen, Claus Dencker; Byskov, Esben

    2008-01-01

    The postbuckling behavior and imperfection sensitivity of the Shanley-Hutchinson plastic model column introduced by Hutchinson in 1973 are examined. The study covers the initial, buckled state and the advanced postbuckling regime of the geometrically perfect realization as well as its sensitivity...

  19. Hutchinson-Gilford Progeria Syndrome: A Rare Genetic Disorder

    Science.gov (United States)

    Panigrahi, Rajat G.; Panigrahi, Antarmayee; Vijayakumar, Poornima; Choudhury, Priyadarshini; Bhuyan, Sanat K.; Bhuyan, Ruchi; Maragathavalli, G.; Pati, Abhishek Ranjan

    2013-01-01

    Hutchinson-Gilford progeria syndrome (HGPS) is a rare pediatric genetic syndrome with incidence of one per eight million live births. The disorder is characterised by premature aging, generally leading to death at approximately 13.4 years of age. This is a follow-up study of a 9-year-old male with clinical and radiographic features highly suggestive of HGPS and presented here with description of differential diagnosis and dental consideration. This is the first case report of HGPS which showed pectus carinatum structure of chest. PMID:24288630

  20. Hutchinson - Gilford progeria syndrome: A rare case report.

    Science.gov (United States)

    Kashyap, Subhash; Shanker, Vinay; Sharma, Neeraj

    2014-10-01

    Hutchinson - Gilford Progeria Syndrome is a rare genetic disorder characterized by premature aging involving the skin, bones, heart, and blood vessels. We report a three-year-old boy with clinical manifestations characteristic of this syndrome. He had a characteristic "plucked-bird" appearance, prominent eyes and scalp veins, senile look, loss of scalp hair, eyebrows, and eyelashes, stunted growth, and mottled pigmentation with sclerodermatous changes over the trunk and lower limbs. Radiological changes and decreased high-density lipoprotein (HDL) levels were also characteristic of the syndrome. This interesting case is reported for its rarity.

  1. Hutchinson – Gilford progeria syndrome: A rare case report

    Science.gov (United States)

    Kashyap, Subhash; Shanker, Vinay; Sharma, Neeraj

    2014-01-01

    Hutchinson – Gilford Progeria Syndrome is a rare genetic disorder characterized by premature aging involving the skin, bones, heart, and blood vessels. We report a three-year-old boy with clinical manifestations characteristic of this syndrome. He had a characteristic “plucked-bird” appearance, prominent eyes and scalp veins, senile look, loss of scalp hair, eyebrows, and eyelashes, stunted growth, and mottled pigmentation with sclerodermatous changes over the trunk and lower limbs. Radiological changes and decreased high-density lipoprotein (HDL) levels were also characteristic of the syndrome. This interesting case is reported for its rarity. PMID:25396134

  2. Hutchinson - Gilford progeria syndrome: A rare case report

    Directory of Open Access Journals (Sweden)

    Subhash Kashyap

    2014-01-01

    Full Text Available Hutchinson - Gilford Progeria Syndrome is a rare genetic disorder characterized by premature aging involving the skin, bones, heart, and blood vessels. We report a three-year-old boy with clinical manifestations characteristic of this syndrome. He had a characteristic "plucked-bird" appearance, prominent eyes and scalp veins, senile look, loss of scalp hair, eyebrows, and eyelashes, stunted growth, and mottled pigmentation with sclerodermatous changes over the trunk and lower limbs. Radiological changes and decreased high-density lipoprotein (HDL levels were also characteristic of the syndrome. This interesting case is reported for its rarity.

  3. Hutchinson-Gilford Progeria Syndrome: A Rare Genetic Disorder

    Directory of Open Access Journals (Sweden)

    Rajat G. Panigrahi

    2013-01-01

    Full Text Available Hutchinson-Gilford progeria syndrome (HGPS is a rare pediatric genetic syndrome with incidence of one per eight million live births. The disorder is characterised by premature aging, generally leading to death at approximately 13.4 years of age. This is a follow-up study of a 9-year-old male with clinical and radiographic features highly suggestive of HGPS and presented here with description of differential diagnosis and dental consideration. This is the first case report of HGPS which showed pectus carinatum structure of chest.

  4. Ocular manifestations in the Hutchinson-Gilford progeria syndrome.

    Science.gov (United States)

    Chandravanshi, Shivcharan L; Rawat, Ashok Kumar; Dwivedi, Prem Chand; Choudhary, Pankaj

    2011-01-01

    The Hutchinson-Gilford progeria (HGP) syndrome is an extremely rare genetic condition characterized by an appearance of accelerated aging in children. The word progeria is derived from the Greek word progeros meaning 'prematurely old'. It is caused by de novo dominant mutation in the LMNA gene (gene map locus 1q21.2) and characterized by growth retardation and accelerated degenerative changes of the skin, musculoskeletal and cardiovascular systems. The most common ocular manifestations are prominent eyes, loss of eyebrows and eyelashes, and lagophthalmos. In the present case some additional ocular features such as horizontal narrowing of palpebral fissure, superior sulcus deformity, upper lid retraction, upper lid lag in down gaze, poor pupillary dilatation, were noted. In this case report, a 15-year-old Indian boy with some additional ocular manifestations of the HGP syndrome is described.

  5. Stem cell depletion in Hutchinson-Gilford progeria syndrome.

    Science.gov (United States)

    Rosengardten, Ylva; McKenna, Tomás; Grochová, Diana; Eriksson, Maria

    2011-12-01

    Hutchinson-Gilford progeria syndrome (HGPS or progeria) is a very rare genetic disorder with clinical features suggestive of premature aging. Here, we show that induced expression of the most common HGPS mutation (LMNA c.1824C>T, p.G608G) results in a decreased epidermal population of adult stem cells and impaired wound healing in mice. Isolation and growth of primary keratinocytes from these mice demonstrated a reduced proliferative potential and ability to form colonies. Downregulation of the epidermal stem cell maintenance protein p63 with accompanying activation of DNA repair and premature senescence was the probable cause of this loss of adult stem cells. Additionally, upregulation of multiple genes in major inflammatory pathways indicated an activated inflammatory response. This response has also been associated with normal aging, emphasizing the importance of studying progeria to increase the understanding of the normal aging process.

  6. Ocular manifestations in the Hutchinson-Gilford progeria syndrome

    Science.gov (United States)

    Chandravanshi, Shivcharan L; Rawat, Ashok Kumar; Dwivedi, Prem Chand; Choudhary, Pankaj

    2011-01-01

    The Hutchinson-Gilford progeria (HGP) syndrome is an extremely rare genetic condition characterized by an appearance of accelerated aging in children. The word progeria is derived from the Greek word progeros meaning ‘prematurely old’. It is caused by de novo dominant mutation in the LMNA gene (gene map locus 1q21.2) and characterized by growth retardation and accelerated degenerative changes of the skin, musculoskeletal and cardiovascular systems. The most common ocular manifestations are prominent eyes, loss of eyebrows and eyelashes, and lagophthalmos. In the present case some additional ocular features such as horizontal narrowing of palpebral fissure, superior sulcus deformity, upper lid retraction, upper lid lag in down gaze, poor pupillary dilatation, were noted. In this case report, a 15-year-old Indian boy with some additional ocular manifestations of the HGP syndrome is described. PMID:22011502

  7. Ocular manifestations in the Hutchinson-Gilford progeria syndrome

    Directory of Open Access Journals (Sweden)

    Shivcharan L Chandravanshi

    2011-01-01

    Full Text Available The Hutchinson-Gilford progeria (HGP syndrome is an extremely rare genetic condition characterized by an appearance of accelerated aging in children. The word progeria is derived from the Greek word progeros meaning ′prematurely old′. It is caused by de novo dominant mutation in the LMNA gene (gene map locus 1q21.2 and characterized by growth retardation and accelerated degenerative changes of the skin, musculoskeletal and cardiovascular systems. The most common ocular manifestations are prominent eyes, loss of eyebrows and eyelashes, and lagophthalmos. In the present case some additional ocular features such as horizontal narrowing of palpebral fissure, superior sulcus deformity, upper lid retraction, upper lid lag in down gaze, poor pupillary dilatation, were noted. In this case report, a 15-year-old Indian boy with some additional ocular manifestations of the HGP syndrome is described.

  8. [Three cases of Hutchinson-Gilford progeria syndrome].

    Science.gov (United States)

    Doubaj, Y; Lamzouri, A; Elalaoui, S-C; Laarabi, F-Z; Sefiani, A

    2011-02-01

    Progeria, or Hutchinson-Gilford syndrome, is a rare genetic disease, characterized by several clinical features that develop in childhood, in particular, an accelerated aging aspect. Its incidence is 1-4 per 8 million newborns. Children with progeria syndrome usually appear normal at birth and in early infancy. Profound failure to thrive occurs during the 1st year. Characteristic facies, partial alopecia progressing to total alopecia, loss of subcutaneous fat, stiffness of joints, bone changes, and abnormal tightness of the skin over the abdomen and upper thighs usually become apparent during the 2nd to 3rd years. Motor and mental development is normal. Patients develop severe atherosclerosis. Death occurs as a result of complications of cardiac or cerebrovascular disease (heart attack or stroke) generally between ages 6 and 20 years. The diagnosis of Hutchinson-Gilford progeria syndrome (HGPS) is based on recognition of common clinical features and the detection of the recurrent p.Gly608Gly mutation in exon 11 of the LMNA gene, which is present in almost all individuals with HGPS. We present here 3 patients aged 5, 11, and 12 years referred to genetic consultation for dysmorphic facies and failure to thrive. After careful clinical examination and paraclinical assessment, the diagnosis of progeria syndrome was raised. We performed molecular analysis for the 3 patients by searching for the recurrent mutation c.1824C>T (p.Gly608Gly) of the LMNA gene, which was found only in 1 patient. We discuss the geneticist's role in the diagnosis of rare dysmorphic syndromes and their genetic counseling. We also analyze the clinical spectrum of HGPS by comparing the 3 patients.

  9. Clinical trial of a farnesyltransferase inhibitor in children with Hutchinson-Gilford progeria syndrome.

    Science.gov (United States)

    Gordon, Leslie B; Kleinman, Monica E; Miller, David T; Neuberg, Donna S; Giobbie-Hurder, Anita; Gerhard-Herman, Marie; Smoot, Leslie B; Gordon, Catherine M; Cleveland, Robert; Snyder, Brian D; Fligor, Brian; Bishop, W Robert; Statkevich, Paul; Regen, Amy; Sonis, Andrew; Riley, Susan; Ploski, Christine; Correia, Annette; Quinn, Nicolle; Ullrich, Nicole J; Nazarian, Ara; Liang, Marilyn G; Huh, Susanna Y; Schwartzman, Armin; Kieran, Mark W

    2012-10-09

    Hutchinson-Gilford progeria syndrome (HGPS) is an extremely rare, fatal, segmental premature aging syndrome caused by a mutation in LMNA that produces the farnesylated aberrant lamin A protein, progerin. This multisystem disorder causes failure to thrive and accelerated atherosclerosis leading to early death. Farnesyltransferase inhibitors have ameliorated disease phenotypes in preclinical studies. Twenty-five patients with HGPS received the farnesyltransferase inhibitor lonafarnib for a minimum of 2 y. Primary outcome success was predefined as a 50% increase over pretherapy in estimated annual rate of weight gain, or change from pretherapy weight loss to statistically significant on-study weight gain. Nine patients experienced a ≥50% increase, six experienced a ≥50% decrease, and 10 remained stable with respect to rate of weight gain. Secondary outcomes included decreases in arterial pulse wave velocity and carotid artery echodensity and increases in skeletal rigidity and sensorineural hearing within patient subgroups. All patients improved in one or more of these outcomes. Results from this clinical treatment trial for children with HGPS provide preliminary evidence that lonafarnib may improve vascular stiffness, bone structure, and audiological status.

  10. Profiles of temperature, salinity, and other measurements from CTD, XBT, and bottle samplers received from the Japan Oceanographic Data Center (NODC Accession 0054093)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Profiles of temperature, salinity, and other measurements received from the Japan Oceanographic Data Center, Hydrographic and Oceanographic Department as a...

  11. Rapamycin activates autophagy in Hutchinson-Gilford progeria syndrome

    Science.gov (United States)

    Graziotto, John J; Cao, Kan; Collins, Francis S

    2012-01-01

    While rapamycin has been in use for years in transplant patients as an antirejection drug, more recently it has shown promise in treating diseases of aging, such as neurodegenerative disorders and atherosclerosis. We recently reported that rapamycin reverses the cellular phenotype of fibroblasts from children with the premature aging disease Hutchinson-Gilford progeria syndrome (HGPS). We found that the causative aberrant protein, progerin, was cleared through autophagic mechanisms when the cells were treated with rapamycin, suggesting a new potential treatment for HGPS. Recent evidence shows that progerin is also present in aged tissues of healthy individuals, suggesting that progerin may contribute to physiological aging. While it is intriguing to speculate that rapamycin may affect normal aging in humans, as it does in lower organisms, it will be important to identify safer analogs of rapamycin for chronic treatments in humans in order to minimize toxicity. In addition to its role in HGPS and normal aging, we discuss the potential of rapamycin for the treatment of age-dependent neurodegenerative diseases. PMID:22170152

  12. Sulforaphane enhances progerin clearance in Hutchinson-Gilford progeria fibroblasts.

    Science.gov (United States)

    Gabriel, Diana; Roedl, Daniela; Gordon, Leslie B; Djabali, Karima

    2015-02-01

    Hutchinson-Gilford progeria syndrome (HGPS, OMIM 176670) is a rare multisystem childhood premature aging disorder linked to mutations in the LMNA gene. The most common HGPS mutation is found at position G608G within exon 11 of the LMNA gene. This mutation results in the deletion of 50 amino acids at the carboxyl-terminal tail of prelamin A, and the truncated protein is called progerin. Progerin only undergoes a subset of the normal post-translational modifications and remains permanently farnesylated. Several attempts to rescue the normal cellular phenotype with farnesyltransferase inhibitors (FTIs) and other compounds have resulted in partial cellular recovery. Using proteomics, we report here that progerin induces changes in the composition of the HGPS nuclear proteome, including alterations to several components of the protein degradation pathways. Consequently, proteasome activity and autophagy are impaired in HGPS cells. To restore protein clearance in HGPS cells, we treated HGPS cultures with sulforaphane (SFN), an antioxidant derived from cruciferous vegetables. We determined that SFN stimulates proteasome activity and autophagy in normal and HGPS fibroblast cultures. Specifically, SFN enhances progerin clearance by autophagy and reverses the phenotypic changes that are the hallmarks of HGPS. Therefore, SFN is a promising therapeutic avenue for children with HGPS.

  13. Temsirolimus Partially Rescues the Hutchinson-Gilford Progeria Cellular Phenotype

    Science.gov (United States)

    Gabriel, Diana; Gordon, Leslie B.

    2016-01-01

    Hutchinson-Gilford syndrome (HGPS, OMIM 176670, a rare premature aging disorder that leads to death at an average age of 14.7 years due to myocardial infarction or stroke, is caused by mutations in the LMNA gene. Lamins help maintain the shape and stability of the nuclear envelope in addition to regulating DNA replication, DNA transcription, proliferation and differentiation. The LMNA mutation results in the deletion of 50 amino acids from the carboxy-terminal region of prelamin A, producing the truncated, farnesylated protein progerin. The accumulation of progerin in HGPS nuclei causes numerous morphological and functional changes that lead to premature cellular senescence. Attempts to reverse this HGPS phenotype have identified rapamycin, an inhibitor of mammalian target of rapamycin (mTOR), as a drug that is able to rescue the HGPS cellular phenotype by promoting autophagy and reducing progerin accumulation. Rapamycin is an obvious candidate for the treatment of HGPS disease but is difficult to utilize clinically. To further assess rapamycin’s efficacy with regard to proteostasis, mitochondrial function and the degree of DNA damage, we tested temsirolimus, a rapamycin analog with a more favorable pharmacokinetic profile than rapamycin. We report that temsirolimus decreases progerin levels, increases proliferation, reduces misshapen nuclei, and partially ameliorates DNA damage, but does not improve proteasome activity or mitochondrial dysfunction. Our findings suggest that future therapeutic strategies should identify new drug combinations and treatment regimens that target all the dysfunctional hallmarks that characterize HGPS cells. PMID:28033363

  14. Hutchinson-Gilford progeria syndrome through the lens of transcription.

    Science.gov (United States)

    Prokocimer, Miron; Barkan, Rachel; Gruenbaum, Yosef

    2013-08-01

    Lamins are nuclear intermediate filaments. In addition to their structural roles, they are implicated in basic nuclear functions such as chromatin organization, DNA replication, transcription, DNA repair, and cell-cycle progression. Mutations in human LMNA gene cause several diseases termed laminopathies. One of the laminopathic diseases is Hutchinson-Gilford progeria syndrome (HGPS), which is caused by a spontaneous mutation and characterized by premature aging. HGPS phenotypes share certain similarities with several apparently comparable medical conditions, such as aging and atherosclerosis, with the conspicuous absence of neuronal degeneration and cancer rarity during the short lifespan of the patients. Cell lines from HGPS patients are characterized by multiple nuclear defects, which include abnormal morphology, altered histone modification patterns, and increased DNA damage. These cell lines provide insight into the molecular pathways including senescence that require lamins A and B1. Here, we review recent data on HGPS phenotypes through the lens of transcriptional deregulation caused by lack of functional lamin A, progerin accumulation, and lamin B1 silencing.

  15. Hutchinson-Gilford progeria syndrome, cardiovascular disease and oxidative stress.

    Science.gov (United States)

    Trigueros-Motos, Laia; Gonzalez, Jose M; Rivera, Jose; Andres, Vicente

    2011-06-01

    Hutchinson-Gilford Progeria Syndrome (HGPS), a rare human disease characterized by premature aging, is mainly caused by the abnormal accumulation of progerin, a mutant form of the mammalian nuclear envelope component lamin A. HGPS patients exhibit vascular alterations and die at an average age of 13 years, predominantly from myocardial infarction or stroke. Animal models of HGPS have been a valuable tool in the study of the pathological processes implicated in the origin of this disease and its associated cardiovascular alterations. Some of the molecular mechanisms of HGPS might be relevant to the process of normal aging, since progerin is detected in cells from normal elderly humans. Conversely, processes linked to normal aging, such as the increase in oxidative stress, might be relevant to the pathogenic mechanisms of HGPS. In this review, we discuss recent advances in the understanding of the molecular mechanisms underlying the cardiovascular alterations associated with HGPS, the potential role of oxidative stress, and therapeutic approaches for the treatment of this devastating disease.

  16. Telomere length in Hutchinson-Gilford progeria syndrome.

    Science.gov (United States)

    Decker, Michelle L; Chavez, Elizabeth; Vulto, Irma; Lansdorp, Peter M

    2009-06-01

    Hutchinson-Gilford Progeria Syndrome (HGPS) is a rare premature aging disorder caused by mutations in the gene LMNA, which encodes the nuclear matrix protein lamin A. Previous research has shown that the average telomere length in fibroblasts from HGPS patients is shorter than in age-matched controls. How mutations in lamin A lead to shortened telomere lengths is not known nor is the contribution of individual chromosome ends to the low average length understood. To measure the telomere length of individual chromosomes, we used quantitative fluorescence in situ hybridization (Q-FISH). In agreement with previous studies, we found that the average telomere length in HPGS fibroblasts is greatly reduced; however, the telomere length at chromosome ends was variable. In contrast, the telomere length in hematopoietic cells which typically do not express lamin A, was within the normal range for three out of four HGPS patient samples. Our results suggest that mutant lamin A decreases telomere length via a direct effect and that expression of mutant LMNA is necessary for telomere loss in HGPS.

  17. Hardy-Petrovitch-Hutchinson's problem and partial theta function

    CERN Document Server

    Kostov, Vladimir Petrov

    2011-01-01

    In 1907 M.Petrovitch initiated the study of a class of entire functions all whose finite sections are real-rooted polynomials. An explicit description of this class in terms of the coefficients of a series is impossible since it is determined by an infinite number of discriminantal inequalities one for each degree. However, interesting necessary or sufficient conditions can be formulated. In particular, J.I.Hutchinson has shown that an entire function p(x)=a_0+a_1x+...+a_nx^n+... with strictly positive coefficients has the property that any its finite segment a_ix^i+...+a_jx^j has all real roots if and only if for all i=1,2,... one has a_i^2/a_{i-1}a_{i+1} is greater than or equal to 4. In the present paper we give sharp lower bounds on the ratios a_i^2/a_{i-1}a_{i+1} for the class considered by M.Petrovitch. In particular, we show that the limit of these minima when i tends to infinity equals the inverse of the maximal positive value of the parameter for which the classical partial theta function belongs to ...

  18. Advances in the study of Hutchinson-Gilford progeria syndrome%Hutchinson-Gilford早老症的研究进展

    Institute of Scientific and Technical Information of China (English)

    李燕辉; 吴白燕

    2006-01-01

    Hutchinson-Gilford早老症(HGPS)为一种极为罕见的遗传性疾病,发生率1/8000000,特征性表现为患儿以极快速度衰老,多数死于冠脉病变引起的心肌梗死或广泛动脉粥样硬化导致的卒中,平均寿命13岁.绝大多数HGPS病例病因为LMNA基因第11个外显子发生点突变(G608G),生成的突变lamin A由显性负效应造成细胞核结构和功能受损.目前该病已有几种动物模型,实验性治疗可以在体外将出泡的细胞核恢复正常.HGPS是研究衰老和心血管疾病机制的一个极好的模型.

  19. Changes in Enterococcal and E coli populations and related antibiotic resistance from medical center to receiving environment

    Science.gov (United States)

    Petit, F.; Berthe, T.; Oberle, K.; Denamur, E.; Clermont, O.; Leclercq, R.; Cattoir, V.; Budzinski, H.

    2013-12-01

    The spread of antibiotic-resistant faecal bacteria and their corresponding genes in water environment, as a result of the overuse of antibiotics, have become an ecological and a public problem. The aim of this multidisciplinary research program (FLASH) -associating chemists, hydrologists, clinical and environmental microbiologists- was to determine to what extent the hospital effluent have an ecological impact on the downstream aquatic environment. For this purpose, fate of Escherichia coli (distribution of phylogenetic groups, antibiotic resistance, integrons- 342 strains) and Enterococci (diversity, antibiotic resistance, genes ermB, mefA, clonal complex 17- 235 strains ) was analyzed in water and sediments along a medical center - WWTP - river - estuary continuum, during a high epidemiologic period in the North west of France. A multi-residue chemical methodology was developed in order to detect low levels of 34 antibiotics in water. To link occurrence of antibiotic-resistant bacteria in water and antibiotic prescription, we use the data collection from the hospital and the antibiotics sales information. In the medical center, the main prescribed antibiotic (amoxicillin) was weakly found in effluents. Along the continuum, contamination of water by antibiotics decreased from 160μg.L-1 (cefotaxim) in hospital effluents to 1ng.L-1 (ofloxacin) in the river. These concentrations were too low to exert a selective pressure (mg.L-1) on antibiotic-resistant bacteria. In same samples, occurrences of antibiotic-resistant E. coli and those harboring a class 1 integrons decreased significantly (p-value Enterococcus populations, E. faecium was mainly isolated (from 89% to 98%). All E. faecium isolates from medical center effluents were multiply antibiotic-resistant, contained erm(B) and mef(A) genes, and belonged to the hospital adapted CC17. The relative proportion of CC17 decreased in favor of other subpopulations, less resistant to antibiotics along the continuum. In the

  20. Hutchinson-Gilford Progeria Syndrome with G608G LMNA Mutation

    Science.gov (United States)

    Kim, Hui Kwon; Lee, Jong Yoon; Bae, Eun Ju; Oh, Phil Soo; Park, Won Il; Lee, Dong Sung; Kim, Jong-Il

    2011-01-01

    Hutchinson-Gilford progeria syndrome (HGPS) is a rare condition originally described by Hutchinson in 1886. Death result from cardiac complications in the majority of cases and usually occurs at average age of thirteen years. A 4-yr old boy had typical clinical findings such as short stature, craniofacial disproportion, alopecia, prominent scalp veins and sclerodermatous skin. This abnormal appearance began at age of 1 yr. On serological and hormonal evaluation, all values are within normal range. He was neurologically intact with motor and mental development. An echocardiogram showed calcification of aortic and mitral valves. Hypertrophy of internal layer at internal carotid artery suggesting atherosclerosis was found by carotid doppler sonography. He is on low dose aspirin to prevent thromboembolic episodes and on regular follow up. Gene study showed typical G608G (GGC- > GGT) point mutation at exon 11 in LMNA gene. This is a rare case of Hutchinson-Gilford progeria syndrome confirmed by genetic analysis in Korea. PMID:22148005

  1. Hutchinson-Gilford progeria syndrome with G608G LMNA mutation.

    Science.gov (United States)

    Kim, Hui Kwon; Lee, Jong Yoon; Bae, Eun Ju; Oh, Phil Soo; Park, Won Il; Lee, Dong Sung; Kim, Jong-Il; Lee, Hong Jin

    2011-12-01

    Hutchinson-Gilford progeria syndrome (HGPS) is a rare condition originally described by Hutchinson in 1886. Death result from cardiac complications in the majority of cases and usually occurs at average age of thirteen years. A 4-yr old boy had typical clinical findings such as short stature, craniofacial disproportion, alopecia, prominent scalp veins and sclerodermatous skin. This abnormal appearance began at age of 1 yr. On serological and hormonal evaluation, all values are within normal range. He was neurologically intact with motor and mental development. An echocardiogram showed calcification of aortic and mitral valves. Hypertrophy of internal layer at internal carotid artery suggesting atherosclerosis was found by carotid doppler sonography. He is on low dose aspirin to prevent thromboembolic episodes and on regular follow up. Gene study showed typical G608G (GGC- > GGT) point mutation at exon 11 in LMNA gene. This is a rare case of Hutchinson-Gilford progeria syndrome confirmed by genetic analysis in Korea.

  2. Advanced postbuckling and imperfection sensitivity of the elastic-plastic Shanley-Hutchinson model column

    DEFF Research Database (Denmark)

    Christensen, Claus Dencker; Byskov, Esben

    2008-01-01

    The postbuckling behavior and imperfection sensitivity of the Shanley-Hutchinson plastic model column introduced by Hutchinson in 1973 are examined. The study covers the initial, buckled state and the advanced postbuckling regime of the geometrically perfect realization as well as its sensitivity...... and the solution to an actual problem is determined by an asymptotic expansion involving hyperbolic trial functions (instead of polynomials) which fulfill general boundary conditions at bifurcation and infinity. The method provides an accurate estimate of the maximum load even if it occurs in an advanced...

  3. 10 Gbit/s mode-multiplexed QPSK transmission using MDM-to-MFDM based single coherent receiver for intra- and inter data center networking

    Science.gov (United States)

    Asif, Rameez; Haithem, Mustafa

    2017-05-01

    Generalized few-mode-fiber (FMF) transmission uses N coherent receivers for mode detection, where N scales with the number of fiber modes. Multiple coherent receivers increase the cost of optical network units (ONUs) in access networks, specifically for intra- and inter data center applications. We have experimentally evaluated a cost effective low-complexity receiver architecture based on mode-division multiplexing (MDM) to mode frequency-division multiplexing (MFDM) conversion for data center connectivity. A single coherent receiver is used to efficiently detect 10 Gbit/s QPSK Nyquist signals over 2.8 km 4-LP mode graded index fiber reducing the ONUs complexity to N / 4 . All the transmitted modes are successfully detected below the forward-error-correction (FEC) limit, i.e. 1×10-3 BER.

  4. The Contributions of Kenelm Hutchinson Digby to Orthopaedics in Hong Kong Part 2

    Directory of Open Access Journals (Sweden)

    Kuo-tai Louis Fu

    2016-06-01

    Full Text Available As the first professor of surgery in Hong Kong, Kenelm Hutchinson Digby had the tremendous task of building a new clinical department in the infant University of Hong Kong from scratch. Despite his heavy commitments in clinical, administrative, and teaching responsibilities, he pioneered novel orthopaedic treatment principles and techniques, in addition to that of general surgery.

  5. Mechanisms of premature vascular aging in children with Hutchinson-Gilford progeria syndrome.

    Science.gov (United States)

    Gerhard-Herman, Marie; Smoot, Leslie B; Wake, Nicole; Kieran, Mark W; Kleinman, Monica E; Miller, David T; Schwartzman, Armin; Giobbie-Hurder, Anita; Neuberg, Donna; Gordon, Leslie B

    2012-01-01

    Hutchinson-Gilford progeria syndrome is a rare, segmental premature aging syndrome of accelerated atherosclerosis and early death from myocardial infarction or stroke. This study sought to establish comprehensive characterization of the fatal vasculopathy in Hutchinson-Gilford progeria syndrome and its relevance to normal aging. We performed cardiovascular assessments at a single clinical site on the largest prospectively studied cohort to date. Carotid-femoral pulse wave velocity was dramatically elevated (mean: 13.00±3.83 m/s). Carotid duplex ultrasound echobrightness, assessed in predefined tissue sites as a measure of arterial wall density, was significantly greater than age- and sex-matched controls in the intima-media (Pnormalizing trends of these noninvasive cardiovascular measures. The data demonstrate that, along with peripheral vascular occlusive disease, accelerated vascular stiffening is an early and pervasive mechanism of vascular disease in Hutchinson-Gilford progeria syndrome. There is considerable overlap with cardiovascular changes of normal aging, which reinforces the view that defining mechanisms of cardiovascular disease in Hutchinson-Gilford progeria syndrome provides a unique opportunity to isolate a subset of factors influencing cardiovascular disease in the general aging population.

  6. Accumulation of Mutant Lamin A Causes Progressive Changes in Nuclear Architecture in Hutchinson-Gilford Progeria Syndrome

    National Research Council Canada - National Science Library

    Robert D. Goldman; Dale K. Shumaker; Michael R. Erdos; Maria Eriksson; Anne E. Goldman; Leslie B. Gordon; Yosef Gruenbaum; Satya Khuon; Melissa Mendez; Renée Varga; Francis S. Collins

    2004-01-01

    Hutchinson-Gilford progeria syndrome (HGPS) is a premature aging disorder, commonly caused by a point mutation in the lamin A gene that results in a protein lacking 50 aa near the C terminus, denoted LAΔ50...

  7. Mutation analysis of the LMNA gene in a child with Hutchinson-Gifford progeria syndrome%Hutchinson-Gilford早老综合征LMNA基因突变研究

    Institute of Scientific and Technical Information of China (English)

    阳芳; 李乾; 郑利雄; 冯思航; 房思宁; 姚勇丰

    2014-01-01

    目的 报告1例Hutchinson-Gilford早老综合征,并进行分子遗传学诊断.方法 提取1例Hutchinson-Gilford早老综合征患儿及其父母外周血DNA,对LMNA基因1 1号外显子和侧翼序列进行测序,并以150例无关系健康人作为对照.结果 患者男,12月龄.出现躯干部紧张如硬皮病样改变、脱发,头皮静脉明显9个月.身高和体重低于同龄儿童平均值2个标准差.头部皮肤菲薄,头皮静脉清晰可见.躯干皮肤紧张变硬有光泽,干燥,少许细小脱屑,皮肤有斑点状色素加深和色素减退夹杂,鹅卵石样的皮肤硬化肥厚,下肢有皮下脂肪凹陷.X线片示指骨末端吸收.患儿LMNA基因11号外显子c.1824C>T杂合点突变(dbSNP:m58596362),父母及健康人对照均未检测到该位点突变.结论 LMNA基因1 1号外显子的c.1824C>T突变为该例Hutchinson-Gilford早老综合征的发病原因.%Objective To report a case of Hutchinson-Gilford progeria syndrome,and to make a molecular genetic diagnosis.Methods Peripheral blood samples were collected from a 12-month-old child with HutchinsonGilford progeria syndrome,his parents,and 150 unrelated healthy controls.DNA was extracted from these samples,and PCR was performed to amplify exon 11 of the LMNA gene and its flanking sequence followed by sequencing.Results The patient presented with scleroderma-like tight skin on the trunk,hair loss and prominent scalp veins for 9 months,whose body height and weight were two standard deviations below the mean.Physical examination showed thin skin and prominent superficial veins over the scalp.The skin over the trunk was tight,hard,shiny and dry with a small number of tiny scales,mottled pigmentation and hypopigmentation,induration and hypertrophy giving a cobblestone-like appearance.The subcutaneous fat was diminished on the lower limbs.Skeletal X-ray examination of the left hand revealed phalangeal acroosteolysis.A known heterozygous mutation c.1824C > T (dbSNP:rs58596362

  8. La presa di parola di Anne Hutchinson. Insubordinazione e conflitto nella giovane America puritana

    Directory of Open Access Journals (Sweden)

    Itala Vivan

    2016-04-01

    Full Text Available Anne Hutchinson lasciò l’Inghilterra nel 1634 per emigrare nel Massachusetts puritano, dove nel 1637 e 1638 fu processata, condannata, scomunicata ed espulsa come donna insubordinata, deviante e pericolosa. Il suo ruolo intellettuale e politico nell’alba incandescente della prima America viene qui analizzato e discusso ascoltando da presso il racconto che promana dalla voce della stessa Anne Hutchinson attraverso i verbali dei due processi, trascritti dai contemporanei con la fedeltà letterale che era tipica del puritanesimo americano. La drammatica controversia che ebbe al centro la presa di parola di questa donna segnò la prima grande crisi della neonata società coloniale – la cosiddetta crisi antinomiana -- e ne determinò gli sviluppi futuri, indirizzandoli verso un sistema di potere politico su basi teocratiche.

  9. Molecular ageing in progeroid syndromes: Hutchinson-Gilford progeria syndrome as a model

    Directory of Open Access Journals (Sweden)

    da Nóbrega Raphael

    2009-04-01

    Full Text Available Abstract Hutchinson-Gilford progeria syndrome (HGPS is a rare premature aging disorder that belongs to a group of conditions called laminopathies which affect nuclear lamins. Mutations in two genes, LMNA and ZMPSTE24, have been found in patients with HGPS. The p.G608G LMNA mutation is the most commonly reported mutation. The aim of this work was to compile a comprehensive literature review of the clinical features and genetic mutations and mechanisms of this syndrome as a contribution to health care workers. This review shows the necessity of a more detailed clinical identification of Hutchinson-Gilford progeria syndrome and the need for more studies on the pharmacologic and pharmacogenomic approach to this syndrome.

  10. Aging of Hutchinson-Gilford progeria syndrome fibroblasts is characterised by hyperproliferation and increased apoptosis.

    Science.gov (United States)

    Bridger, Joanna M; Kill, Ian R

    2004-05-01

    Hutchinson-Gilford progeria syndrome is a rare genetic disorder that mimics certain aspects of aging prematurely. Recent work has revealed that mutations in the lamin A gene are a cause of the disease. We show here that cellular aging of Hutchinson-Gilford progeria syndrome fibroblasts is characterised by a period of hyperproliferation and terminates with a large increase in the rate of apoptosis. The occurrence of cells with abnormal nuclear morphology reported by others is shown to be a result of cell division since the fraction of these abnormalities increases with cellular age. Similarly, the proportion of cells with an abnormal or absent A-type lamina increases with age. These data provide clues as to the cellular basis for premature aging in HGPS and support the view that cellular senescence and tissue homeostasis are important factors in the normal aging process.

  11. Werner and Hutchinson-Gilford progeria syndromes: mechanistic basis of human progeroid diseases.

    Science.gov (United States)

    Kudlow, Brian A; Kennedy, Brian K; Monnat, Raymond J

    2007-05-01

    Progeroid syndromes have been the focus of intense research in part because they might provide a window into the pathology of normal ageing. Werner syndrome and Hutchinson-Gilford progeria syndrome are two of the best characterized human progeroid diseases. Mutated genes that are associated with these syndromes have been identified, mouse models of disease have been developed, and molecular studies have implicated decreased cell proliferation and altered DNA-damage responses as common causal mechanisms in the pathogenesis of both diseases.

  12. Single-Center Retrospective Evaluation of Inhaled Corticosteroid Use for Chronic Obstructive Pulmonary Disease Exacerbation Patients Receiving Systemic Corticosteroids.

    Science.gov (United States)

    Steuber, Taylor; Shiltz, Dane

    2016-11-01

    Purpose: To determine the frequency of inappropriate inhaled corticosteroid (ICS) therapy when it is prescribed concurrently with systemic corticosteroids; to identify cost-savings potential in the setting of chronic obstructive pulmonary disease (COPD) exacerbations. Methods: Patients admitted to 1 of 8 hospital locations utilizing an integrated electronic health record within the health system for COPD exacerbations treated with systemic corticosteroids (equivalent to at least 30 mg of oral prednisone) between July 1, 2013 and June 30, 2014 were included in a retrospective chart review. Endpoints assessed included number of ICS, with or without long-acting beta-2 agonists (LABA), respiratory medications potentially wasted due to overlap therapy with systemic corticosteroids, as well as overall cost attributed to drug product, administration products, and respiratory therapy labor cost from potentially inappropriate overlap therapy. Results were extrapolated based on the number of admissions within the specified time period. Length of stay data were also compared between the 2 groups (overlap therapy vs no overlap therapy) to determine whether overlap therapy results in a reduction of hospital stay. Results: A total of 10,710 admissions were identified and 74 charts were randomly identified for review. Forty-six (62%) patients received at least one dose of overlapping ICS or ICS/LABA. One hundred forty-two nebulized budesonide vials were wasted along with 43 ICS or ICS/LABA inhalers. A total cost of $8,152.75 was attributed to drug product, administration products, and labor cost. Extrapolating to the 10,710 admissions identified, there would potentially be 20,551 wasted budesonide vials and 6,223 wasted ICS or ICS/LABA inhalers, resulting in an estimated annual cost savings of $1,180,090.03 for the health system. Additionally, length of stay was shorter in the group not receiving overlap therapy compared to the group receiving overlap therapy, but it was not

  13. Profile of patients receiving medical care at a reference, support, and treatment center for psoriasis patients at a university hospital*

    Science.gov (United States)

    Cordeiro Júnior, Túlio Germano Machado; Andrade, Bruno D' Paula; Palitot, Esther Bastos; Piuvezam, Márcia Regina; Mascarenhas, Sandra Rodrigues

    2016-01-01

    Psoriasis is a chronic, inflammatory, immune-mediated disease affecting 1-3% of the population worldwide. This work seeks to draw a profile of patients with psoriasis, analyzing socioeconomic, anthropometric, and clinical aspects. For this, medical records from 81 individuals who received medical care in a university hospital in 2014 were consulted. It was observed that the patients were mostly dark-skinned black adult men, with a low education level and a low income, who were sedentary, former smokers, obese, with an increase in waist circumference, and who did not consume alcohol. Psoriasis vulgaris predominated, beginning mainly on the scalp, hands, and feet. In addition, many presented some type of associated comorbidity and had relatives with psoriasis. PMID:27828656

  14. Pattern of palliative care, pain management and referral trends in patients receiving radiotherapy at a tertiary cancer center

    Directory of Open Access Journals (Sweden)

    Kuldeep Sharma

    2009-01-01

    Full Text Available Background: Pain is a common primary symptom of advanced cancer and metastatic disease, occurring in 50-75% of all patients. Although palliative care and pain management are essential components in oncology practice, studies show that these areas are often inadequately addressed. Materials and Methods: We randomly selected 152 patients receiving palliative radiotherapy (PRT from October 2006 to August 2008, excluding metastatic bone lesions. Patients′ records were studied retrospectively. Results: A median follow-up of 21 weeks was available for 119 males and 33 females with a median age of 55 years. Maximum (60% patients were of head and neck cancers followed by esophagus (14%, lung (10% and others. Dysphagia, growth/ulcer and pain were the chief indications for PRT. Pain was present in 93 (61% cases out of which, 56 (60% were referred to pain clinic. All except one consulted pain clinic with a median pain score of 8 (0-10 point scale. Fifty-three of these 56 patients (96% received opioid-based treatment with adequate pain relief in 33% cases and loss of follow-up in 40% cases. Only five (3% cases were referred to a hospice. Twenty-two (14% cases were considered for radical treatment following excellent response to PRT. Conclusion: In this selective sample, the standard of analgesic treatment was found to be satisfactory. However, there is a lot of scope for improvement regarding referral to pain clinic and later to the hospice. Patients′ follow-up needs to be improved along with future studies evaluating those patients who were considered for further RT till radical dose. Programs to change the patients′ attitude towards palliative care, physicians′ (residents′ training to improve communication skills, and institutional policies may be promising strategies.

  15. Radiological Diagnosis of a Rare Premature Aging Genetic Disorder: Progeria (Hutchinson-Gilford Syndrome

    Directory of Open Access Journals (Sweden)

    Haji Mohammed Nazir

    2017-01-01

    Full Text Available Hutchinson-Gilford Progeria Syndrome (HGPS is a rare disease with a combination of short stature, bone abnormalities, premature ageing, and skin changes. Though the physical appearance of these patients is characteristic, there is little emphasis on the characteristic radiological features. In this paper, we report a 16-year-old boy with clinical and radiological features of this rare genetic disorder. He had a characteristic facial appearance with a large head, large eyes, thin nose with beaked tip, small chin, protruding ears, prominent scalp veins, and absence of hair.

  16. Dental and craniofacial characteristics in a patient with Hutchinson-Gilford progeria syndrome.

    Science.gov (United States)

    Reichert, Christoph; Gölz, Lina; Götz, Werner; Wolf, Michael; Deschner, James; Jäger, Andreas

    2014-07-01

    The Hutchinson-Gilford progeria syndrome (HGPS) is an exceptionally rare medical disorder caused by mutations in the lamin A/C gene. Affected patients display typical features of premature aging. Beside general medical disorders, these patients have several specific features related to the craniofacial phenotype and the oral cavity. In this article, the dental and craniofacial characteristics of a 9-year-old girl with HGPS are presented. It is the first report addressing orthodontic tooth movement and microbiological features in a HGPS patient. We describe and discuss pathologic findings and provide a detailed histology of the teeth which had to be extracted during initial treatment.

  17. Model of human aging: Recent findings on Werner’s and Hutchinson-Gilford progeria syndromes

    Directory of Open Access Journals (Sweden)

    Shian-ling Ding

    2008-09-01

    Full Text Available Shian-ling Ding1, Chen-Yang Shen2,3,41Department of Nursing, Kang-Ning Junior College of Medical Care and Management, Taipei, Taiwan; 2Institute of Biomedical Sciences, and 3Life Science Library, Academia Sinica, Taipei, Taiwan; 4Graduate Institute of Environmental Science, China Medical University, Taichong, TaiwanAbstract: The molecular mechanisms involved in human aging are complicated. Two progeria syndromes, Werner’s syndrome (WS and Hutchinson-Gilford progeria syndrome (HGPS, characterized by clinical features mimicking physiological aging at an early age, provide insights into the mechanisms of natural aging. Based on recent findings on WS and HGPS, we suggest a model of human aging. Human aging can be triggered by two main mechanisms, telomere shortening and DNA damage. In telomere-dependent aging, telomere shortening and dysfunction may lead to DNA damage responses which induce cellular senescence. In DNA damage-initiated aging, DNA damage accumulates, along with DNA repair deficiencies, resulting in genomic instability and accelerated cellular senescence. In addition, aging due to both mechanisms (DNA damage and telomere shortening is strongly dependent on p53 status. These two mechanisms can also act cooperatively to increase the overall level of genomic instability, triggering the onset of human aging phenotypes.Keywords: human aging, Hutchinson-Gilford Progeria syndrome, Werner syndrome

  18. All-trans retinoic acid and rapamycin normalize Hutchinson Gilford progeria fibroblast phenotype.

    Science.gov (United States)

    Pellegrini, Camilla; Columbaro, Marta; Capanni, Cristina; D'Apice, Maria Rosaria; Cavallo, Carola; Murdocca, Michela; Lattanzi, Giovanna; Squarzoni, Stefano

    2015-10-06

    Hutchinson Gilford progeria syndrome is a fatal disorder characterized by accelerated aging, bone resorption and atherosclerosis, caused by a LMNA mutation which produces progerin, a mutant lamin A precursor. Progeria cells display progerin and prelamin A nuclear accumulation, altered histone methylation pattern, heterochromatin loss, increased DNA damage and cell cycle alterations. Since the LMNA promoter contains a retinoic acid responsive element, we investigated if all-trans retinoic acid administration could lower progerin levels in cultured fibroblasts. We also evaluated the effect of associating rapamycin, which induces autophagic degradation of progerin and prelamin A. We demonstrate that all-trans retinoic acid acts synergistically with low-dosage rapamycin reducing progerin and prelamin A, via transcriptional downregulation associated with protein degradation, and increasing the lamin A to progerin ratio. These effects rescue cell dynamics and cellular proliferation through recovery of DNA damage response factor PARP1 and chromatin-associated nuclear envelope proteins LAP2α and BAF. The combined all-trans retinoic acid-rapamycin treatment is dramatically efficient, highly reproducible, represents a promising new approach in Hutchinson-Gilford Progeria therapy and deserves investigation in ageing-associated disorders.

  19. Treatment considerations in hutchinson-gilford progeria syndrome: a case report.

    Science.gov (United States)

    Hazan-Molina, H; Aizenbud, D; Dror, Aizenbud D

    2015-01-01

    Hutchinson-Guilford progeria syndrome is an extremely rare condition classified as one of the premature ageing syndromes. This case presents a 16-year-old Israeli female patient, suffering from a variant of Hutchinson-Guilford progeria with a history of treatment with oral biphosphnates. The patient presented with typical cranial and facial features of the syndrome including delayed teeth eruption and root development probably due to insufficient jaw growth and severs retrognatic position of the maxilla and mandible. Orthodontic treatment considerations are described along with those required in light of the previous treatment by oral biphosphonates.All primary teeth were extracted in three appointments while creating as minimal trauma as possible to the surrounding tissue and alveolar bone. For now, the patient refuses to begin the orthodontic treatment course. There are no limitations to conduct any dental procedures in progeria patients, however, extreme caution must be exercised during oral surgery due to the inelasticity of tissues and dermal atrophy. Orthodontic procedure commencement should be early enough to manage the delayed development and eruption of teeth. Patients taking oral biphosphonates should be advised of this potential complication. If orthodontic treatment is considered appropriate, plans should be assessed and modified to include compromises.

  20. Study of the Rate and Causes of Islamshahr Urban Residents’ Voiding to Refer to the Health Centers for Receiving Health Services (2003

    Directory of Open Access Journals (Sweden)

    P Ghazy Sharei

    2005-05-01

    Full Text Available Background: It was believed that Inhabitant of Islamshahr avoid referring to their health centers and health posts to receive bargain medical services. In search for the rate and causes of such neglect, this study was formed. Materials and Methods: In a cross-sectional study from all urban centers and health posts under the supervision of Islamshahr health network, 712 files were selected randomly. Results: Investigating the selected files it revealed that 25% were complete, 51% were defective and 24% were blank. In other words, only 25% of the files were complete and 75% of the files showed lack of full participation in primary care services. In the process of evaluation of each separate service unit, more defective files were found in family planning and oral health programs. But in the prenatal care and growth observation units, the number of complete files was a little higher than the number of defective ones. This is probably justifiable de to free vaccination of children and pregnant women, which causes the customer to refer to the mentioned units. In search for the causes of this lack of participation, 533 defective files were selected and those families were interviewed through some questionnaires. Conclusion: In family planning and growth observation and prenatal care, the interviewees believed that there was no need for them to seek such services. This in turn shows their lack of knowledge about the necessity of these cares. In case of oral health, lack of such unite in the health center was mentioned as the reason. More details are discussed in the article.

  1. Ann Hutchinson (as subject), Dr. Joan Vernikos (R), Dee O'Hara (L), J. Evans and E. Lowe pose for

    Science.gov (United States)

    1993-01-01

    Ann Hutchinson (as subject), Dr. Joan Vernikos (R), Dee O'Hara (L), J. Evans and E. Lowe pose for pictures in the NASA Magazine aritcle 'How it Feels to be a Human Test Subject' as they prepare for a bed rest study to simulate the efects of microgravity on the human body.

  2. Aging Study, Hints from Hutchinson-Gilford Progeria Syndrome%Hutchinson-Gilford早老症在衰老研究中的意义

    Institute of Scientific and Technical Information of China (English)

    宋昱; 郭翯; 郑璐; 陈琳; 黄昱

    2009-01-01

    Hutchinson-Gilford早老症是一种散发的常染体显性遗传病,是研究人类正常衰老理想的疾病模型.其发病机制在于核纤层蛋白A的基因发生突变,使其翻译产物缺少了50个氨基酸而变成早老蛋白,该蛋白质在细胞内积累,导致细胞增殖异常、端粒缩短、基因表达调控异常、基因组不稳定等,这些表现与正常衰老有诸多相似之处.正常衰老细胞中同样发现早老蛋白的存在,且随年龄增长而积累.本文比较了HGPS与正常衰老在表型上的异同,综述了HGPS加速衰老的分子机制研究进展,并着重介绍了HGPS研究成果对衰老研究的借鉴意义.%time. By comparing and contrasting the phenotype of HGPS with that of normal aging, we summarize the research progress in the molec-ular mechanism of HGPS, and focus on the results from HGPS which can be used on aging research.

  3. Aberrant DNA methylation profiles in the premature aging disorders Hutchinson-Gilford Progeria and Werner syndrome

    Science.gov (United States)

    Heyn, Holger; Moran, Sebastian; Esteller, Manel

    2013-01-01

    DNA methylation gradiently changes with age and is likely to be involved in aging-related processes with subsequent phenotype changes and increased susceptibility to certain diseases. The Hutchinson-Gilford Progeria (HGP) and Werner Syndrome (WS) are two premature aging diseases showing features of common natural aging early in life. Mutations in the LMNA and WRN genes were associated to disease onset; however, for a subset of patients the underlying causative mechanisms remain elusive. We aimed to evaluate the role of epigenetic alteration on premature aging diseases by performing comprehensive DNA methylation profiling of HGP and WS patients. We observed profound changes in the DNA methylation landscapes of WRN and LMNA mutant patients, which were narrowed down to a set of aging related genes and processes. Although of low overall variance, non-mutant patients revealed differential DNA methylation at distinct loci. Hence, we propose DNA methylation to have an impact on premature aging diseases. PMID:23257959

  4. Extradural hematoma surgery in a child with Hutchinson-Gilford progeria syndrome: Perioperative concerns.

    Science.gov (United States)

    Hansda, Upendra; Agarwal, Jyotsna; Patra, Chitralekha; Ganjoo, Pragati

    2013-05-01

    Hutchinson-Gilford progeria syndrome (HGPS) is a very rare genetic disorder characterized by premature ageing, severe growth failure, and very early onset atherosclerosis. Psychologically and emotionally child-like, these patients suffer from physiological changes of old age. Early and progressive atherosclerosis of intra-cranial vessels in HGPS patients, along with a thin skin and fragile vessels, make these patients susceptible to intra-cranial hematomas following relatively trivial injuries and to severe intra-cranial disease. Anesthetizing HGPS patients for surgery can be challenging due to the presence of a possible difficult airway, multi-system derangements, and associated skin, bone and joint disease. We report here one such child with HGPS who underwent craniotomy and evacuation of an extradural hematoma that developed after minor head trauma. Securing his airway during surgery was difficult.

  5. Vascular disease modeling using induced pluripotent stem cells: Focus in Hutchinson-Gilford Progeria Syndrome.

    Science.gov (United States)

    Pitrez, P R; Rosa, S C; Praça, C; Ferreira, L

    2016-05-06

    Induced pluripotent stem cells (iPSCs) represent today an invaluable tool to create disease cell models for modeling and drug screening. Several lines of iPSCs have been generated in the last 7 years that changed the paradigm for studying diseases and the discovery of new drugs to treat them. In this article we focus our attention to vascular diseases in particular Hutchinson-Gilford Progeria Syndrome (HGPS), a devastating premature aging disease caused by a mutation in the lamin A gene. In general, patients die because of myocardial infarction or stroke. Because the patients are fragile the isolation of a particular type of cells is very difficult. Therefore in the last 5 years, researchers have used cells derived from iPSCs to model aspects of the HGPS and to screen libraries of chemicals to retard or treat the disease.

  6. Aberrant DNA methylation profiles in the premature aging disorders Hutchinson-Gilford Progeria and Werner syndrome.

    Science.gov (United States)

    Heyn, Holger; Moran, Sebastian; Esteller, Manel

    2013-01-01

    DNA methylation gradiently changes with age and is likely to be involved in aging-related processes with subsequent phenotype changes and increased susceptibility to certain diseases. The Hutchinson-Gilford Progeria (HGP) and Werner Syndrome (WS) are two premature aging diseases showing features of common natural aging early in life. Mutations in the LMNA and WRN genes were associated to disease onset; however, for a subset of patients the underlying causative mechanisms remain elusive. We aimed to evaluate the role of epigenetic alteration on premature aging diseases by performing comprehensive DNA methylation profiling of HGP and WS patients. We observed profound changes in the DNA methylation landscapes of WRN and LMNA mutant patients, which were narrowed down to a set of aging related genes and processes. Although of low overall variance, non-mutant patients revealed differential DNA methylation at distinct loci. Hence, we propose DNA methylation to have an impact on premature aging diseases.

  7. Extradural hematoma surgery in a child with Hutchinson-Gilford progeria syndrome: Perioperative concerns

    Directory of Open Access Journals (Sweden)

    Upendra Hansda

    2013-01-01

    Full Text Available Hutchinson-Gilford progeria syndrome (HGPS is a very rare genetic disorder characterized by premature ageing, severe growth failure, and very early onset atherosclerosis. Psychologically and emotionally child-like, these patients suffer from physiological changes of old age. Early and progressive atherosclerosis of intra-cranial vessels in HGPS patients, along with a thin skin and fragile vessels, make these patients susceptible to intra-cranial hematomas following relatively trivial injuries and to severe intra-cranial disease. Anesthetizing HGPS patients for surgery can be challenging due to the presence of a possible difficult airway, multi-system derangements, and associated skin, bone and joint disease. We report here one such child with HGPS who underwent craniotomy and evacuation of an extradural hematoma that developed after minor head trauma. Securing his airway during surgery was difficult.

  8. Hutchinson-Gilford progeria syndrome caused by an LMNA mutation: a case report.

    Science.gov (United States)

    Chu, Yan; Xu, Zi-Gang; Xu, Zhe; Ma, Lin

    2015-01-01

    Hutchinson-Gilford progeria syndrome is a rare genetic disorder characterized by premature aging of the skin, bones, heart, and blood vessels. We report a 6-year-old boy who was born at full term but presented with scleroderma-like appearance at 1 month of age and gradually developed clinical manifestations of progeria. He had characteristic facial features of prominent eyes, scalp, and leg veins; loss of scalp hair, eyebrows, and eyelashes; stunted growth; scleroderma-like changes of the skin; and a premature aged appearance. Metabolic investigations showed transient methylmalonic aciduria, and genetic testing of the peripheral blood identified the c.1824C>T heterozygous LMNA mutation. The present case is reported because of its rarity.

  9. Hutchinson-Gilford progeria syndrome with severe calcific aortic valve stenosis

    Directory of Open Access Journals (Sweden)

    Natesh B Hanumanthappa

    2011-01-01

    Full Text Available Hutchinson-Gilford progeria syndrome (HGPS is a rare premature aging syndrome that results from mutation in the Laminin A gene. This case report of a 12-year-old girl with HGPS is presented for the rarity of the syndrome and the classical clinical features that were observed in the patient. All patients with this condition should undergo early and periodic evaluation for cardiovascular diseases. However, the prognosis is poor and management is mainly conservative. There is no proven therapy available. Mortality in this uniformly fatal condition is primarily due to myocardial infarction, strokes or congestive cardiac failure between ages 7 and 21 years due to the rapidly progressive arteriosclerosis involving the large vessels.

  10. A 36 years old woman with Hutchinson-Gilford Progeria Syndrome: a case report

    Directory of Open Access Journals (Sweden)

    Akrami S M

    2007-10-01

    Full Text Available Background: Hutchinson-Gilford Progeria Syndrome (HGPS is a very rare genetic disorder with a frequency of 1 in 8 million live births. It is characterised by premature aging phenotype. The median age at death is 13.4 years. It is an autosomal dominat disease due to a de novo point mutation in the Lamin A gene exon 11 in the majority of cases. More than 100 cases have been reported world wide."nCase report: We describe here an exceptionally long-lived patient with HGPS, who is alive at age 36. She was referred by a cardiologist to our endocrinology clinic to be worked up for presence of a metabolic or genetic disorder before a heart surgery."nResults: Having more attention of clinicians about very rare diseases and referring the patients to geneticist are the main goals of this case report as well as describing the disease.

  11. DNA repair defects and genome instability in Hutchinson-Gilford Progeria Syndrome.

    Science.gov (United States)

    Gonzalo, Susana; Kreienkamp, Ray

    2015-06-01

    The integrity of the nuclear lamina has emerged as an important factor in the maintenance of genome stability. In particular, mutations in the LMNA gene, encoding A-type lamins (lamin A/C), alter nuclear morphology and function, and cause genomic instability. LMNA gene mutations are associated with a variety of degenerative diseases and devastating premature aging syndromes such as Hutchinson-Gilford Progeria Syndrome (HGPS) and Restrictive Dermopathy (RD). HGPS is a severe laminopathy, with patients dying in their teens from myocardial infarction or stroke. HGPS patient-derived cells exhibit nuclear shape abnormalities, changes in epigenetic regulation and gene expression, telomere shortening, genome instability, and premature senescence. This review highlights recent advances in identifying molecular mechanisms that contribute to the pathophysiology of HGPS, with a special emphasis on DNA repair defects and genome instability.

  12. Hip pathology in Hutchinson-Gilford progeria syndrome: a report of two children.

    Science.gov (United States)

    Akhbari, Pouya; Jha, Shilpa; James, Kyle D; Hinves, Barry L; Buchanan, Jamie A F

    2012-11-01

    Hutchinson-Gilford progeria syndrome (HGPS) is a rare genetic disorder. The estimated incidence is one in 4 million births. Orthopaedic manifestations include abnormality of the hips occurring early in the disease process. Severe coxa valga can be apparent by the age of 2 years. We report two cases of HGPS, one in a 7-year-old girl with avascular necrosis of the left hip and the second in a 13-year-old girl with recurrent traumatic hip dislocations. We demonstrate the pathoanatomical changes in the hip with HGPS using a combination of imaging modalities including radiographic, computed tomographic and MRI scans. These include coxa magna, coxa valga and acetabular dysplasia. We also comment on how these would affect the surgical management of this high-risk group of patients.

  13. Oral and maxillofacial surgical considerations for a case of Hutchinson-Gilford progeria.

    Science.gov (United States)

    Batstone, M D; Macleod, A W G

    2002-11-01

    Hutchinson-Guilford progeria is a rare genetic condition showing the stigmata of accelerated ageing combined with severe growth retardation. Patients with this condition show a classical facies and clinical features with an average age of death of 13, usually due to atherosclerotic changes. Craniofacial and dental manifestations include mandibular and maxillary hypoplasia, both vertically and horizontally. Delayed and abnormal tooth eruption and morphology are commonly present. The long-term medical prognosis and eruption potential of individual teeth is important when considering treatment. In addition to this, surgical planning and surgical technique must be modified by the abnormal facial morphology, dermal inelasticity, potential anaesthetic difficulties, and ongoing deterioration in the medical condition. These factors mandate early and definitive intervention for oral surgical conditions. We report the case of a 13-year-old male treated for pericoronitis and oral pain relating to delayed eruption of first permanent molars.

  14. Improvement in Depressive Symptoms Among Hispanic/Latinos Receiving a Culturally Tailored IMPACT and Problem-Solving Intervention in a Community Health Center.

    Science.gov (United States)

    Camacho, Álvaro; González, Patricia; Castañeda, Sheila F; Simmons, Alan; Buelna, Christina; Lemus, Hector; Talavera, Gregory A

    2015-05-01

    The present study investigated whether a culturally-tailored problem-solving intervention delivered by a trained depression care specialist (DCS) would improve depressive symptoms over a 6 month period among Hispanic/Latino patients in a federally-qualified community health center by the California-Mexico border. Participants included 189 low income Hispanic/Latino patients of Mexican heritage. Based on the improving mood-promoting access to collaborative treatment (IMPACT) evidence-based treatment, patients received evidence-based problem-solving therapy. The Patient Health Questionnaire-9 (PHQ-9) was administered to assess changes in self-reported depressive symptoms between baseline and monthly for a 6-month follow up period. The majority of participants were female (72.5%) with a mean age of 52.5 (SD = 11.7). The mean PHQ-9 at baseline was 16.9 (SD = 4.0) and at the 6-month follow-up, the average PHQ-9 decreased to 9.9 (SD = 5.7). A linear mixed model analysis showed significant improvement in PHQ-9 scores over a 6 month period (F = 124.1; p Hispanic/Latino low-income patients.

  15. Hypoparathyroidism in an Egyptian child with Hutchinson-Gilford progeria syndrome: a case report

    Science.gov (United States)

    2012-01-01

    Introduction Hutchinson-Gilford progeria syndrome is a rare genetic disorder. It is reported to be present in one in eight million and is characterized by severe growth failure, early loss of hair, lipodystrophy, scleroderma, decreased joint mobility, osteolysis, early atherosclerosis and facial features that resemble those of an aged person. Apart from diabetes mellitus, there are no reported abnormalities of thyroid, parathyroid, pituitary or adrenal function. Here, we report the case of a 10-year-old Egyptian child with Hutchinson-Gilford progeria syndrome and hypoparathyroidism. Case presentation A 10-year-old Egyptian boy was referred to our institution for an evaluation of recurrent attacks of muscle cramps, paresthesia of his fingertips and perioral numbness of two months duration. On examination, we found dilated veins present over his scalp with alopecia and frontal bossing, a beaked nose, thin lips, protruding ears, a high pitched voice with sparse hair over his eyebrows and eyelashes and micrognathia but normal dentition. His eyes appeared prominent and our patient appeared to have poor sexual development. A provisional diagnosis of progeria was made, which was confirmed by molecular genetics study. Chvostek's and Trousseau's signs were positive. He had low total calcium (5.4 mg/dL), low ionized calcium (2.3 mg/dL), raised serum phosphate (7.2 mg/dL), raised alkaline phosphatase (118 U/L) and low intact parathyroid hormone (1.2 pg/mL) levels. He was started on oral calcium salt and vitamin D; his symptoms improved with the treatment and his serum calcium, urinary calcium and alkaline phosphates level were monitored every three months to ensure adequacy of therapy and to avoid hypercalcemia. Conclusion Routine checking of serum calcium, phosphorus and parathyroid hormone will help in the early detection of hypoparathyrodism among children with progeria. PMID:22251708

  16. A ceRNA analysis on LMNA gene focusing on the Hutchinson-Gilford progeria syndrome

    Science.gov (United States)

    2013-01-01

    Background Hutchinson-Gilford progeria syndrome is a rare dominant human disease of genetic origin. The average life expectancy is about 20 years, patients’ life quality is still very poor and no efficient therapy has yet been developed. It is caused by mutation of the LMNA gene, which results in accumulation in the nuclear membrane of a particular splicing form of Lamin-A called progerin. The mechanism by which progerin perturbs cellular homeostasis and leads to the symptoms is still under debate. Micro-RNAs are able to negatively regulate transcription by coupling with the 3’ UnTranslated Region of messenger RNAs. Several Micro-RNAs recognize the same 3’ UnTranslated Region and each Micro-RNA can recognize multiple 3’ UnTranslated Regions of different messenger RNAs. When different messenger RNAs are co-regulated via a similar panel of micro-RNAs, these messengers are called Competing Endogenous RNAs, or ceRNAs. The 3’ UnTranslated Region of the longest LMNA transcript was analysed looking for its ceRNAs. The aim of this study was to search for candidate genes and gene ontology functions possibly influenced by LMNA mutations that may exert a role in progeria development. Results 11 miRNAs were isolated as potential LMNA regulators. By computational analysis, the miRNAs pointed to 17 putative LMNA ceRNAs. Gene ontology analysis of isolated ceRNAs showed an enrichment in RNA interference and control of cell cycle functions. Conclusion This study isolated novel genes and functions potentially involved in LMNA network of regulation that could be involved in laminopathies such as the Hutchinson-Gilford progeria syndrome. PMID:23317481

  17. Hypoparathyroidism in an Egyptian child with Hutchinson-Gilford progeria syndrome: a case report

    Directory of Open Access Journals (Sweden)

    Kalil Kotb

    2012-01-01

    Full Text Available Abstract Introduction Hutchinson-Gilford progeria syndrome is a rare genetic disorder. It is reported to be present in one in eight million and is characterized by severe growth failure, early loss of hair, lipodystrophy, scleroderma, decreased joint mobility, osteolysis, early atherosclerosis and facial features that resemble those of an aged person. Apart from diabetes mellitus, there are no reported abnormalities of thyroid, parathyroid, pituitary or adrenal function. Here, we report the case of a 10-year-old Egyptian child with Hutchinson-Gilford progeria syndrome and hypoparathyroidism. Case presentation A 10-year-old Egyptian boy was referred to our institution for an evaluation of recurrent attacks of muscle cramps, paresthesia of his fingertips and perioral numbness of two months duration. On examination, we found dilated veins present over his scalp with alopecia and frontal bossing, a beaked nose, thin lips, protruding ears, a high pitched voice with sparse hair over his eyebrows and eyelashes and micrognathia but normal dentition. His eyes appeared prominent and our patient appeared to have poor sexual development. A provisional diagnosis of progeria was made, which was confirmed by molecular genetics study. Chvostek's and Trousseau's signs were positive. He had low total calcium (5.4 mg/dL, low ionized calcium (2.3 mg/dL, raised serum phosphate (7.2 mg/dL, raised alkaline phosphatase (118 U/L and low intact parathyroid hormone (1.2 pg/mL levels. He was started on oral calcium salt and vitamin D; his symptoms improved with the treatment and his serum calcium, urinary calcium and alkaline phosphates level were monitored every three months to ensure adequacy of therapy and to avoid hypercalcemia. Conclusion Routine checking of serum calcium, phosphorus and parathyroid hormone will help in the early detection of hypoparathyrodism among children with progeria.

  18. Prematurely aged children: molecular alterations leading to Hutchinson-Gilford progeria and Werner syndromes.

    Science.gov (United States)

    Domínguez-Gerpe, Lourdes; Araújo-Vilar, David

    2008-12-01

    Ageing is thought to be a polygenic and stochastic process in which multiple mechanisms operate at the same time. At the level of the individual organism ageing is associated with a progressive deterioration of health and quality of life, sharing common features such as: alopecia and grey hair, loss of audition, macular degeneration, neurodegeneration, cardiovascular diseases, osteoporosis, cataract formation, type-2 diabetes, lipodystrophies; a generally increased susceptibility to infection, autoimmune disorders and diseases such as cancer; and an impaired ability to cope with stress. Recent studies of mechanisms involved in the ageing process are contributing to the identification of genes involved in longevity. Monogenic heritable disorders causing premature ageing, and animal models have contributed to the understanding of some of the characteristic organism-level features associated with human ageing. Werner syndrome and Hutchinson-Gilford progeria syndrome are the best characterized human disorders. Werner syndrome patients have a median life expectancy of 47 years with clinical conditions from the second decade of life. Hutchinson-Gilford progeria syndrome patients die at a median age of 11-13 years with clinical conditions appearing soon after birth. In both syndromes, alterations in specific genes have been identified, with mutations in the WRN and LMNA genes respectively being the most closely associated with each syndrome. Results from molecular studies strongly suggest an increase in DNA damage and cell senescence as the underlying mechanism of pathological premature ageing in these two human syndromes. The same general mechanism has also been observed in human cells undergoing the normal ageing process. In the present article the molecular mechanisms currently proposed for explaining these two syndromes, which may also partly explain the normal ageing process, are reviewed.

  19. Impact of Farnesylation Inhibitors on Survival in Hutchinson-Gilford Progeria Syndrome

    Science.gov (United States)

    Gordon, Leslie B.; Massaro, Joe; D'Agostino, Ralph B.; Campbell, Susan E.; Brazier, Joan; Brown, W. Ted; Kleinman, Monica E; Kieran, Mark W.

    2014-01-01

    Background Hutchinson-Gilford progeria syndrome is an ultra-rare segmental premature aging disease resulting in early death from heart attack or stroke. There is no approved treatment, but starting in 2007, several recent single arm clinical trials have administered inhibitors of protein farnesylation aimed at reducing toxicity of the disease-producing protein progerin. No study has assessed whether treatments influence patient survival. The key elements necessary for this analysis are a robust natural history of survival and comparison with a sufficiently large patient population that has been treated for a sufficient time period with disease-targeting medications. Methods and Results We generated survival Kaplan-Meier survival analyses for the largest untreated Hutchinson-Gilford progeria syndrome cohort to date. Mean survival was 14.6 years. Comparing survival for treated versus age-and-gender-matched untreated cohorts, hazard ratio was 0.13 (95% CI 0.04-0.37; P<0.001) with median follow-up of 5.3 years from time of treatment initiation. There were 21/43 deaths in untreated versus 5/43 deaths among treated subjects. Treatment increased mean survival by 1.6 years. Conclusions This study provides a robust untreated disease survival profile, which can be utilized for comparisons now and in the future to assess changes in survival with treatments for HGPS. The current comparisons estimating increased survival with protein farnesylation inhibitors provide the first evidence of treatments influencing survival for this fatal disease. Clinical Trial Registration Information www.clinicaltrials.gov. Indentifiers: NCT00425607, NCT00879034 and NCT00916747. PMID:24795390

  20. Temsirolimus for patients with metastatic renal cell carcinoma: outcomes in patients receiving temsirolimus within a compassionate use program in a tertiary referral center

    Directory of Open Access Journals (Sweden)

    Afshar M

    2014-12-01

    Full Text Available Mehran Afshar,1,* Jennifer Pascoe,1,2,* Sue Whitmarsh,1 Nicholas James,1,3 Emilio Porfiri1,2 1Queen Elizabeth Hospital Birmingham NHS Foundation Trust, 2Cancer Research UK Clinical Trials Unit, School of Cancer Sciences, University of Birmingham, Birmingham, UK; 3Cancer Research Unit, Clinical Trials Unit, University of Warwick, Coventry, UK *These authors have contribute equally to this work Aim: Temsirolimus has shown efficacy as first-line treatment of patients with metastatic renal cell carcinoma and poor prognostic features. The efficacy of temsirolimus in other clinical settings, such as second-line therapy, is unclear. The aim of this study was to investigate the outcomes of an unselected group of patients with renal cancer treated with temsirolimus in a compassionate use program. Patients and methods: This retrospective analysis included all patients receiving temsirolimus at a tertiary referral center between November 2007 and October 2008. Information was obtained through review of patient notes, electronic records, and pharmacy records. Baseline characteristics, prognostic features, and previous treatments were recorded for all patients. Outcome measures were response rate, progression-free survival (PFS, overall survival (OS, and toxicities. Results: Thirty-eight patients were included in the analysis, with median age of 62 years, among whom 37% were untreated and 63% had received one or more previous treatments. Thirty-four percent of the patients had three or more poor prognostic factors. Four patients (11% achieved a partial response (PR; in all four of these patients, the PR was confirmed by two subsequent computed tomography (CT scans, and in one patient, the PR lasted for more than 18 months. A total of 34% achieved stable disease, and 50% had disease progression. Median OS was 7.6 months (95% confidence interval [CI] 4.8–10.5, and median PFS was 3.2 months (95% CI 1.0–5.5. Patients with two or fewer poor prognostic factors

  1. Prognostic and Predictive Factors in Patients with Advanced Penile Cancer Receiving Salvage (2nd or Later Line) Systemic Treatment: A Retrospective, Multi-Center Study

    Science.gov (United States)

    Buonerba, Carlo; Di Lorenzo, Giuseppe; Pond, Gregory; Cartenì, Giacomo; Scagliarini, Sarah; Rozzi, Antonio; Quevedo, Fernando J.; Dorff, Tanya; Nappi, Lucia; Lanzetta, Gaetano; Pagliaro, Lance; Eigl, Bernhard J.; Naik, Gurudatta; Ferro, Matteo; Galdiero, Mariano; De Placido, Sabino; Sonpavde, Guru

    2016-01-01

    Introduction and objectives: Metastatic penile squamous cell carcinoma (PSCC) is associated with dismal outcomes with median overall survival (OS) of 6–12 months in the first-line and <6 months in the salvage setting. Given the rarity of this disease, randomized trials are difficult. Prognostic risk models may assist in rational drug development by comparing observed outcomes in nonrandomized phase II studies and retrospective data vs. predicted outcomes based on baseline prognostic factors in the context of historically used agents. In this retrospective study, we constructed a prognostic model in the salvage setting of PSCC patients receiving second or later line systemic treatment, and also explored differences in outcomes based on type of treatment. Materials and methods: We performed a chart review to identify patients with locally advanced unresectable or metastatic PSCC who received second or later line systemic treatment in centers from North America and Europe. The primary outcome was OS from initiation of treatment, with secondary outcomes being progression-free survival (PFS) and response rate (RR). OS was estimated using the Kaplan-Meier method. Cox proportional hazards regression was used to identify prognostic factors for outcomes using univariable and multivariable models. Results: Sixty-five patients were eligible. Seventeen of 63 evaluable patients had a response (27.0%, 95% confidence interval [CI] = 16.6–39.7%) and median OS and PFS were 20 (95% CI = 20–21) and 12 (95% CI = 12, 16) weeks, respectively. Visceral metastasis (VM) and hemoglobin (Hb) ≤ 10 gm/dl were consistently significant poor prognostic factors for both OS and PFS, and Hb was also prognostic for response. The 28 patients with neither risk factor had a median OS (95% CI) of 24 (20–40) weeks and 1-year (95% CI) OS of 13.7% (4.4–42.7%), while the 37 patients with 1 or 2 risk factors had median OS (95% CI) of 20 (16–20) weeks and 1-year (95% CI) OS of 6.7% (1.8–24

  2. 早老症的分子机制%Molecular mechanism of Hutchinson-Gilford Progeria Syndrome

    Institute of Scientific and Technical Information of China (English)

    刘新光; 赵炜; 周中军

    2010-01-01

    @@ 儿童早老症(Hutchinson Giford Progeria Syn-drome,HGPS)是由于基因突变导致的疾病,它的发病率很低,大概是八百万分之一,患者出生的早期就开始出现衰老的容貌"[1]. 这种疾病最早由Hutchins于1886年报道"[2],1904年Gilford报道了第二例,他在文章中使用了progeria(早老)这个词[3].1962年,DeBusk总结了60例病例,其中包括4例他本人报道的病人,他将这种疾病命名为Hutchinson-Giford Progefia Syndrome,HGPS.

  3. Investigation into the human premature ageing disease, Hutchinson Gilford Progeria syndrome, using hTERT immortalised fibroblasts

    OpenAIRE

    Worthington, Gemma Louise

    2016-01-01

    This thesis was submitted for the award of Doctor of Philosophy and was awarded by Brunel University London Hutchinson Gilford Progeria syndrome (HGPS) is a rare premature ageing disease affecting children. 80% of “classic” HGPS patients share the same mutation in the LMNA gene that gives rise to characteristics similar to normal human ageing and they usually die in their teens from heart attacks or strokes. Cells taken from progeria patients have a short replicative lifespan in culture an...

  4. Clinical and radiographic features of Hutchinson-Gilford progeria syndrome: A case report.

    Science.gov (United States)

    Alves, Daniel Berretta; Silva, Juliana Melo; Menezes, Tatiany Oliveira; Cavaleiro, Rosely Santos; Tuji, Fabrício Mesquita; Lopes, Marcio Ajudarte; Zaia, Alexandre Augusto; Coletta, Ricardo Della

    2014-03-16

    Hutchinson-Gilford progeria syndrome (HGPS) is a rare dysmorphic syndrome characterized by several features of premature aging with clinical involvement of the skin, bones, and cardiovascular system. HGPS has an estimated incidence of one in four million to one in eight million births. The main clinical features of HGPS include short stature, craniofacial dimorphism, alopecia, bone fragility, and cardiovascular disorders. The most frequent cause of death is myocardial infarction at a mean age of 13 years old. Dental manifestations include delayed development and eruption of teeth, discoloration, crowding and rotation of teeth, and displaced teeth. Cone beam computed tomography images revealed the absence of the sphenoid, frontal, and maxillary sinus, flattening of the condyles and glenoid fossa, and bilateral hypoplasia of the mandibular condyles. The disease is caused by mutations in lamin A/C (LMNA). Here, we present a case report of an 11-year-old boy with classical features of HGPS, which was caused by a de novo germ-line mutation (C1824T, G608G) in exon 11 of the LMNA gene. Some uncommon HGPS-associated features in our patient, such as alterations in the facial sinuses and hypoplasia of the condyles, contributed to the expansion of the phenotypic spectrum of this syndrome from a dentomaxillofacial perspective.

  5. Abberent expression analysis of LMNA gene in hutchinson-gilford progeria syndrome

    Science.gov (United States)

    Navid, Afifa; Khan, Mohammad Haroon; Rashid, Hamid

    2012-01-01

    Hutchinson-Gilford progeria syndrome (HGPS) is caused by de novo dominant point mutations of the genes encoding nuclear lamina proteins, leading towards premature aging. A protein sequence is subjected to mutations in nature which can affect the function and folding pattern of the protein by different ways. Mutations involved in HGPS were identified and were substituted in the seed sequence retrieved from the UniProt database to get the mutated versions. Tertiary structure of the Lamin A protein was previously unpredicted so was performed for all the mutated as well as for the seed protein to analyze the effects of mutations on the protein structure, folding and interactions. All the predicted models were refined and validated through multiple servers for multiple parameters. The validated 3D structure of seed protein was then successfully submitted to the Protein Model Database and was assigned with the PMDB ID PM0077829. All the predicted structures were superimposed with a root mean square deviation value of 7.0 Å and a high Dali Z-score of 1.9. It was observed that mutations affected physiochemical properties as well as instability index and thus is affecting the domains in specific and the whole structure in general. It was further analyzed that HGPS is the result of affected Lamin a protein interactions with other integral and binding proteins in the inner nuclear membrane affecting the link in between the nuclear membrane and the network of the lamina. PMID:22493523

  6. Vitamin D receptor signaling improves Hutchinson-Gilford progeria syndrome cellular phenotypes.

    Science.gov (United States)

    Kreienkamp, Ray; Croke, Monica; Neumann, Martin A; Bedia-Diaz, Gonzalo; Graziano, Simona; Dusso, Adriana; Dorsett, Dale; Carlberg, Carsten; Gonzalo, Susana

    2016-05-24

    Hutchinson-Gilford Progeria Syndrome (HGPS) is a devastating incurable premature aging disease caused by accumulation of progerin, a toxic lamin A mutant protein. HGPS patient-derived cells exhibit nuclear morphological abnormalities, altered signaling pathways, genomic instability, and premature senescence. Here we uncover new molecular mechanisms contributing to cellular decline in progeria. We demonstrate that HGPS cells reduce expression of vitamin D receptor (VDR) and DNA repair factors BRCA1 and 53BP1 with progerin accumulation, and that reconstituting VDR signaling via 1α,25-dihydroxyvitamin D3 (1,25D) treatment improves HGPS phenotypes, including nuclear morphological abnormalities, DNA repair defects, and premature senescence. Importantly, we discovered that the 1,25D/VDR axis regulates LMNA gene expression, as well as expression of DNA repair factors. 1,25D dramatically reduces progerin production in HGPS cells, while stabilizing BRCA1 and 53BP1, two key factors for genome integrity. Vitamin D/VDR axis emerges as a new target for treatment of HGPS and potentially other lamin-related diseases exhibiting VDR deficiency and genomic instability. Because progerin expression increases with age, maintaining vitamin D/VDR signaling could keep the levels of progerin in check during physiological aging.

  7. MECHANISMS OF PREMATURE VASCULAR AGING IN CHILDREN WITH HUTCHINSON-GILFORD PROGERIA SYNDROME

    Science.gov (United States)

    Gerhard-Herman, Marie; Smoot, Leslie B.; Wake, Nicole; Kieran, Mark W.; Kleinman, Monica E.; Miller, David T.; Schwartzman, Armin; Giobbie-Hurder, Anita; Neuberg, Donna; Gordon, Leslie B.

    2011-01-01

    Hutchinson-Gilford progeria syndrome (HGPS) is a rare, segmental premature aging syndrome of accelerated atherosclerosis and early death from myocardial infarction or stroke. This study sought to establish comprehensive characterization of the fatal vasculopathy in HGPS and its relevance to normal aging. We performed cardiovascular assessments at a single clinical site on the largest prospectively studied cohort to date. Carotid-femoral pulse wave velocity was dramatically elevated (mean 13.00±3.83 m/s). Carotid duplex ultrasound echobrightness, assessed in predefined tissue sites as a measure of arterial wall density, was significantly greater than age- and gender-matched controls in the intima-media (P<0.02), near adventitia (P<0.003) and deep adventitia (P<0.01), as was internal carotid artery mean flow velocity (p<0.0001). Ankle-brachial indices were abnormal in 78% of patients. Effective disease treatments may be heralded by normalizing trends of these noninvasive cardiovascular measures. The data demonstrates that, along with peripheral vascular occlusive disease, accelerated vascular stiffening is an early and pervasive mechanism of vascular disease in HGPS. There is considerable overlap with cardiovascular changes of normal aging, which reinforces the view that defining mechanisms of cardiovascular disease in HGPS provides a unique opportunity to isolate a subset of factors influencing cardiovascular disease in the general aging population. PMID:22083160

  8. Hutchinson-Gilford progeria syndrome as a model for vascular aging.

    Science.gov (United States)

    Brassard, Jonathan A; Fekete, Natalie; Garnier, Alain; Hoesli, Corinne A

    2016-02-01

    Hutchinson-Gilford progeria syndrome (HGPS) is a premature aging disorder caused by a de novo genetic mutation that leads to the accumulation of a splicing isoform of lamin A termed progerin. Progerin expression alters the organization of the nuclear lamina and chromatin. The life expectancy of HGPS patients is severely reduced due to critical cardiovascular defects. Progerin also accumulates in an age-dependent manner in the vascular cells of adults that do not carry genetic mutations associated with HGPS. The molecular mechanisms that lead to vascular dysfunction in HGPS may therefore also play a role in vascular aging. The vascular phenotypic and molecular changes observed in HGPS are strikingly similar to those seen with age, including increased senescence, altered mechanotransduction and stem cell exhaustion. This article discusses the similarities and differences between age-dependent and HGPS-related vascular aging to highlight the relevance of HGPS as a model for vascular aging. Induced pluripotent stem cells derived from HGPS patients are suggested as an attractive model to study vascular aging in order to develop novel approaches to treat cardiovascular disease.

  9. DNA-damage accumulation and replicative arrest in Hutchinson-Gilford progeria syndrome.

    Science.gov (United States)

    Musich, Phillip R; Zou, Yue

    2011-12-01

    A common feature of progeria syndromes is a premature aging phenotype and an enhanced accumulation of DNA damage arising from a compromised repair system. HGPS (Hutchinson-Gilford progeria syndrome) is a severe form of progeria in which patients accumulate progerin, a mutant lamin A protein derived from a splicing variant of the lamin A/C gene (LMNA). Progerin causes chromatin perturbations which result in the formation of DSBs (double-strand breaks) and abnormal DDR (DNA-damage response). In the present article, we review recent findings which resolve some mechanistic details of how progerin may disrupt DDR pathways in HGPS cells. We propose that progerin accumulation results in disruption of functions of some replication and repair factors, causing the mislocalization of XPA (xeroderma pigmentosum group A) protein to the replication forks, replication fork stalling and, subsequently, DNA DSBs. The binding of XPA to the stalled forks excludes normal binding by repair proteins, leading to DSB accumulation, which activates ATM (ataxia telangiectasia mutated) and ATR (ATM- and Rad3-related) checkpoints, and arresting cell-cycle progression.

  10. Rapamycin reverses cellular phenotypes and enhances mutant protein clearance in Hutchinson-Gilford progeria syndrome cells.

    Science.gov (United States)

    Cao, Kan; Graziotto, John J; Blair, Cecilia D; Mazzulli, Joseph R; Erdos, Michael R; Krainc, Dimitri; Collins, Francis S

    2011-06-29

    Hutchinson-Gilford progeria syndrome (HGPS) is a lethal genetic disorder characterized by premature aging. HGPS is most commonly caused by a de novo single-nucleotide substitution in the lamin A/C gene (LMNA) that partially activates a cryptic splice donor site in exon 11, producing an abnormal lamin A protein termed progerin. Accumulation of progerin in dividing cells adversely affects the integrity of the nuclear scaffold and leads to nuclear blebbing in cultured cells. Progerin is also produced in normal cells, increasing in abundance as senescence approaches. Here, we report the effect of rapamycin, a macrolide antibiotic that has been implicated in slowing cellular and organismal aging, on the cellular phenotypes of HGPS fibroblasts. Treatment with rapamycin abolished nuclear blebbing, delayed the onset of cellular senescence, and enhanced the degradation of progerin in HGPS cells. Rapamycin also decreased the formation of insoluble progerin aggregates and induced clearance through autophagic mechanisms in normal fibroblasts. Our findings suggest an additional mechanism for the beneficial effects of rapamycin on longevity and encourage the hypothesis that rapamycin treatment could provide clinical benefit for children with HGPS.

  11. Progerin reduces LAP2α-telomere association in Hutchinson-Gilford progeria.

    Science.gov (United States)

    Chojnowski, Alexandre; Ong, Peh Fern; Wong, Esther S M; Lim, John S Y; Mutalif, Rafidah A; Navasankari, Raju; Dutta, Bamaprasad; Yang, Henry; Liow, Yi Y; Sze, Siu K; Boudier, Thomas; Wright, Graham D; Colman, Alan; Burke, Brian; Stewart, Colin L; Dreesen, Oliver

    2015-08-27

    Hutchinson-Gilford progeria (HGPS) is a premature ageing syndrome caused by a mutation in LMNA, resulting in a truncated form of lamin A called progerin. Progerin triggers loss of the heterochromatic marker H3K27me3, and premature senescence, which is prevented by telomerase. However, the mechanism how progerin causes disease remains unclear. Here, we describe an inducible cellular system to model HGPS and find that LAP2α (lamina-associated polypeptide-α) interacts with lamin A, while its interaction with progerin is significantly reduced. Super-resolution microscopy revealed that over 50% of telomeres localize to the lamina and that LAP2α association with telomeres is impaired in HGPS. This impaired interaction is central to HGPS since increasing LAP2α levels rescues progerin-induced proliferation defects and loss of H3K27me3, whereas lowering LAP2 levels exacerbates progerin-induced defects. These findings provide novel insights into the pathophysiology underlying HGPS, and how the nuclear lamina regulates proliferation and chromatin organization.

  12. Bilateral stenosis of carotid siphon in Hutchinson-Gilford progeria syndrome.

    Science.gov (United States)

    Narazaki, Ryo; Makimura, Mika; Sanefuji, Masafumi; Fukamachi, Shigeru; Akiyoshi, Hidetaka; So, Hidenori; Yamamura, Kenichiro; Doisaki, Sayoko; Kojima, Seiji; Ihara, Kenji; Hara, Toshiro; Ohga, Shouichi

    2013-08-01

    Hutchinson-Gilford progeria syndrome (HGPS) is a rare premature aging disease, caused by a de novo mutation of lamin-A gene, LMNA G608G. Accumulation of abnormal lamin-A (progerin) compromises nuclear membrane integrity and results in the accelerated senescence. Affected patients show a typical feature of birdlike face, alopecia, sclerotic skin, loss of subcutaneous fat, and short stature with advancing years. Neonatal scleroderma is the first presentation, although early diagnosis is challenging. The leading cause of death is cardio-/cerebro-vascular accidents associated with atherosclerosis. However, not all findings may recapitulate the aging process. We herein report a 9-year-old Japanese male with HGPS who developed cerebral infarction. The genetic study of peripheral blood-derived DNA determined a heterozygous c.1824C>T mutation, p.G608G. Telomere length of lymphocytes was normal. Bilateral stenosis of carotid siphons was prominent, while systemic arteriosclerosis was unremarkable assessed by the ankle-brachial index, carotid ultrasound imaging and funduscopic study. HGPS patients have marked loss and functional defects in vascular smooth muscle cells, leading to the vulnerability to circulatory stress. Symmetrical stenosis of siphons might occur as a distinctive cerebral vasculopathy of HGPS, rather than simple vascular senescence. Peripheral blood study on LMNA G608G and telomere length could screen progerias in infancy for early therapeutic intervention.

  13. Drug screening on Hutchinson Gilford progeria pluripotent stem cells reveals aminopyrimidines as new modulators of farnesylation.

    Science.gov (United States)

    Blondel, S; Egesipe, A-L; Picardi, P; Jaskowiak, A-L; Notarnicola, M; Ragot, J; Tournois, J; Le Corf, A; Brinon, B; Poydenot, P; Georges, P; Navarro, C; Pitrez, P R; Ferreira, L; Bollot, G; Bauvais, C; Laustriat, D; Mejat, A; De Sandre-Giovannoli, A; Levy, N; Bifulco, M; Peschanski, M; Nissan, X

    2016-02-18

    Hutchinson-Gilford progeria syndrome (HGPS) is a rare genetic disorder characterized by a dramatic appearance of premature aging. HGPS is due to a single-base substitution in exon 11 of the LMNA gene (c.1824C>T) leading to the production of a toxic form of the prelamin A protein called progerin. Because farnesylation process had been shown to control progerin toxicity, in this study we have developed a screening method permitting to identify new pharmacological inhibitors of farnesylation. For this, we have used the unique potential of pluripotent stem cells to have access to an unlimited and relevant biological resource and test 21,608 small molecules. This study identified several compounds, called monoaminopyrimidines, which target two key enzymes of the farnesylation process, farnesyl pyrophosphate synthase and farnesyl transferase, and rescue in vitro phenotypes associated with HGPS. Our results opens up new therapeutic possibilities for the treatment of HGPS by identifying a new family of protein farnesylation inhibitors, and which may also be applicable to cancers and diseases associated with mutations that involve farnesylated proteins.

  14. Effect of progerin on the accumulation of oxidized proteins in fibroblasts from Hutchinson Gilford progeria patients.

    Science.gov (United States)

    Viteri, Gabriela; Chung, Youn Wook; Stadtman, Earl R

    2010-01-01

    The mutation responsible for Hutchinson Gilford Progeria Syndrome (HGPS) causes abnormal nuclear morphology. Previous studies show that free radicals and reactive oxygen species play major roles in the etiology and/or progression of neurodegenerative diseases and aging. This study compares oxidative stress responses between progeric and normal fibroblasts. Our data revealed higher ROS levels in HGPS cells compared to age-matched controls. In response to oxidative challenge, progeric cells showed increased mRNA levels for mitochondrial superoxide dismutase (SOD) and SOD protein content. However, this did not prevent a drop in the ATP content of progeria fibroblasts. Previous studies have shown that declines in human fibroblast ATP levels interfere with programmed cell death and promote necrotic inflammation. Notably, in our investigations the ATP content of progeria fibroblasts was only approximately 50% of that found in healthy controls. Furthermore, HGPS fibroblast analysis revealed a decrease in total caspase-like proteasome activity and in the levels of two active proteolytic complex subunits (beta(5) and beta(7)). A number of studies indicate that the molecular mechanisms causing accelerated aging in progeric patients also occur in healthy cells of older individuals. Thus, the results of this study may also help explain some of the cellular changes that accompany normal aging.

  15. Metformin Alleviates Aging Cellular Phenotypes in Hutchinson-Gilford Progeria Syndrome Dermal Fibroblasts.

    Science.gov (United States)

    Park, Seul-Ki; Shin, Ok Sarah

    2017-02-13

    Metformin is a popular antidiabetic biguanide, which has been considered as a candidate drug for cancer treatment and aging prevention. Hutchinson-Gilford progeria syndrome (HGPS) is a devastating disease characterized by premature aging and severe age-associated complications leading to death. The effects of metformin on HGPS dermal fibroblasts remain largely undefined. In this study, we investigated whether metformin could exert a beneficial effect on nuclear abnormalities and delay senescence in fibroblasts derived from HGPS patients. Metformin treatment partially restored normal nuclear phenotypes, delayed senescence, activated the phosphorylation of AMP-activated protein kinase, and decreased reactive oxygen species formation in HGPS dermal fibroblasts. Interestingly, metformin reduced the number of phosphorylated histone variant H2AX-positive DNA damage foci and suppressed progerin protein expression, compared to the control. Furthermore, metformin-supplemented aged mice showed higher splenocyte proliferation and mRNA expression of the antioxidant enzyme, superoxide dismutase 2 than the control mice. Collectively, our results show that metformin treatment alleviates the nuclear defects and premature aging phenotypes in HGPS fibroblasts. Thus, metformin can be considered a promising therapeutic approach for life extension in HGPS. This article is protected by copyright. All rights reserved.

  16. A-type lamins and Hutchinson-Gilford progeria syndrome: pathogenesis and therapy.

    Science.gov (United States)

    Gonzalez, Jose M; Pla, Davinia; Perez-Sala, Dolores; Andres, Vicente

    2011-06-01

    Lamin A and lamin C (A-type lamins, both encoded by the LMNA gene) are major components of the mammalian nuclear lamina, a complex proteinaceous structure that acts as a scaffold for protein complexes that regulate nuclear structure and function. Abnormal accumulation of farnesylated-progerin, a mutant form of prelamin A, plays a key role in the pathogenesis of the Hutchinson-Gilford progeria syndrome (HGPS), a devastating disorder that causes the death of affected children at an average age of 13.5 years, predominantly from premature atherosclerosis and myocardial infarction or stroke. Remarkably, progerin is also present in normal cells and appears to progressively accumulate during aging of non-HGPS cells. Therefore, understanding how this mutant form of lamin A provokes HGPS may shed significant insight into physiological aging. In this review, we discuss recent advances into the pathogenic mechanisms underlying HGPS, the main murine models of the disease, and the therapeutic strategies developed in cellular and animal models with the aim of reducing the accumulation of farnesylated-progerin, as well as their use in clinical trials of HGPS.

  17. Interruption of progerin–lamin A/C binding ameliorates Hutchinson-Gilford progeria syndrome phenotype

    Science.gov (United States)

    Lee, Su-Jin; Jung, Youn-Sang; Yoon, Min-Ho; Kang, So-mi; Oh, Ah-Young; Lee, Jee-Hyun; Jun, So-Young; Woo, Tae-Gyun; Chun, Ho-Young; Kim, Sang Kyum; Chung, Kyu Jin; Lee, Ho-Young; Lee, Kyeong; Jin, Guanghai; Na, Min-Kyun; Ha, Nam Chul; Bárcena, Clea; Freije, José M.P.; López-Otín, Carlos; Song, Gyu Yong

    2016-01-01

    Hutchinson-Gilford progeria syndrome (HGPS) is a rare autosomal dominant genetic disease that is caused by a silent mutation of the LMNA gene encoding lamins A and C (lamin A/C). The G608G mutation generates a more accessible splicing donor site than does WT and produces an alternatively spliced product of LMNA called progerin, which is also expressed in normal aged cells. In this study, we determined that progerin binds directly to lamin A/C and induces profound nuclear aberrations. Given this observation, we performed a random screening of a chemical library and identified 3 compounds (JH1, JH4, and JH13) that efficiently block progerin–lamin A/C binding. These 3 chemicals, particularly JH4, alleviated nuclear deformation and reversed senescence markers characteristic of HGPS cells, including growth arrest and senescence-associated β-gal (SA–β-gal) activity. We then used microarray-based analysis to demonstrate that JH4 is able to rescue defects of cell-cycle progression in both HGPS and aged cells. Furthermore, administration of JH4 to LmnaG609G/G609G-mutant mice, which phenocopy human HGPS, resulted in a marked improvement of several progeria phenotypes and an extended lifespan. Together, these findings indicate that specific inhibitors with the ability to block pathological progerin–lamin A/C binding may represent a promising strategy for improving lifespan and health in both HGPS and normal aging. PMID:27617860

  18. Aggrecan expression is substantially and abnormally upregulated in Hutchinson-Gilford Progeria Syndrome dermal fibroblasts.

    Science.gov (United States)

    Lemire, Joan M; Patis, Carrie; Gordon, Leslie B; Sandy, John D; Toole, Bryan P; Weiss, Anthony S

    2006-08-01

    Hutchinson-Gilford Progeria syndrome (HGPS) is a rare genetic disorder that displays features of segmental aging. It is manifested predominantly in connective tissue, with most prominent histological changes occurring in the skin, cartilage, bone and cardiovascular tissues. Detailed quantitative real time reverse-transcription polymerase chain reaction studies confirmed the previous observation that platelet-derived growth factor A-chain transcripts are consistently elevated 11+/-2- to 13+/-2-fold in two HGPS dermal fibroblast lines compared with age-matched controls. Furthermore, we identified two additional genes with substantially altered transcript levels. Nucleotide pyrophosphatase transcription was virtually shut down with decreased expression of 13+/-3- to 59+/-3-fold in HGPS, whereas aggrecan mRNA was elevated to 24+/-5 times to 41+/-4 times that of chronologically age-matched controls. Aggrecan, normally a component of cartilage and not always detectable in normal fibroblasts cultures, was secreted by HGPS fibroblast lines and was produced as a proteoglycan. This demonstrates that elevated aggrecan expression and its secretion are aberrant features of HGPS. We conclude that HGPS cells can display massively altered transcript levels leading to the secretion of inappropriate protein species.

  19. Interruption of progerin-lamin A/C binding ameliorates Hutchinson-Gilford progeria syndrome phenotype.

    Science.gov (United States)

    Lee, Su-Jin; Jung, Youn-Sang; Yoon, Min-Ho; Kang, So-Mi; Oh, Ah-Young; Lee, Jee-Hyun; Jun, So-Young; Woo, Tae-Gyun; Chun, Ho-Young; Kim, Sang Kyum; Chung, Kyu Jin; Lee, Ho-Young; Lee, Kyeong; Jin, Guanghai; Na, Min-Kyun; Ha, Nam Chul; Bárcena, Clea; Freije, José M P; López-Otín, Carlos; Song, Gyu Yong; Park, Bum-Joon

    2016-10-03

    Hutchinson-Gilford progeria syndrome (HGPS) is a rare autosomal dominant genetic disease that is caused by a silent mutation of the LMNA gene encoding lamins A and C (lamin A/C). The G608G mutation generates a more accessible splicing donor site than does WT and produces an alternatively spliced product of LMNA called progerin, which is also expressed in normal aged cells. In this study, we determined that progerin binds directly to lamin A/C and induces profound nuclear aberrations. Given this observation, we performed a random screening of a chemical library and identified 3 compounds (JH1, JH4, and JH13) that efficiently block progerin-lamin A/C binding. These 3 chemicals, particularly JH4, alleviated nuclear deformation and reversed senescence markers characteristic of HGPS cells, including growth arrest and senescence-associated β-gal (SA-β-gal) activity. We then used microarray-based analysis to demonstrate that JH4 is able to rescue defects of cell-cycle progression in both HGPS and aged cells. Furthermore, administration of JH4 to LmnaG609G/G609G-mutant mice, which phenocopy human HGPS, resulted in a marked improvement of several progeria phenotypes and an extended lifespan. Together, these findings indicate that specific inhibitors with the ability to block pathological progerin-lamin A/C binding may represent a promising strategy for improving lifespan and health in both HGPS and normal aging.

  20. Increased expression of the Hutchinson-Gilford progeria syndrome truncated lamin A transcript during cell aging.

    Science.gov (United States)

    Rodriguez, Sofia; Coppedè, Fabio; Sagelius, Hanna; Eriksson, Maria

    2009-07-01

    Most cases of the segmental progeroid syndrome, Hutchinson-Gilford progeria syndrome (HGPS), are caused by a de novo dominant mutation within a single codon of the LMNA gene. This mutation leads to the increased usage of an internal splice site that generates an alternative lamin A transcript with an internal deletion of 150 nucleotides, called lamin A Delta 150. The LMNA gene encodes two major proteins of the inner nuclear lamina, lamins A and C, but not much is known about their expression levels. Determination of the overall expression levels of the LMNA gene transcripts is an important step to further the understanding of the HGPS. In this study, we have performed absolute quantification of the lamins A, C and A Delta 150 transcripts in primary dermal fibroblasts from HGPS patients and unaffected age-matched and parent controls. We show that the lamin A Delta 150 transcript is present in unaffected controls but its expression is >160-fold lower than that in samples from HGPS patients. Analysis of transcript expression during in vitro aging shows that although the levels of lamin A and lamin C transcripts remain unchanged, the lamin A Delta 150 transcript increases in late passage cells from HGPS patients and parental controls. This study provides a new method for LMNA transcript analysis and insights into the expression of the LMNA gene in HGPS and normal cells.

  1. Progeria of stem cells: stem cell exhaustion in Hutchinson-Gilford progeria syndrome.

    Science.gov (United States)

    Halaschek-Wiener, Julius; Brooks-Wilson, Angela

    2007-01-01

    Hutchinson-Gilford progeria syndrome (HGPS) is a rare, fatal genetic disorder that is characterized by segmental accelerated aging. The major causal mutation associated with HGPS triggers abnormal messenger RNA splicing of the lamin A gene leading to changes in the nuclear architecture. To date, two models have been proposed to explain how mutations in the lamin A gene could lead to HGPS, structural fragility and altered gene expression. We favor a compatible model that links HGPS to stem cell-driven tissue regeneration. In this model, nuclear fragility of lamin A-deficient cells increases apoptotic cell death to levels that exhaust tissues' ability for stem cell-driven regeneration. Tissue-specific differences in cell death or regenerative potential, or both, result in the tissue-specific segmental aging pattern seen in HGPS. We propose that the pattern of aging-related conditions present or absent in HGPS can provide insight into the genetic and environmental factors that contribute to normal aging.

  2. School Accommodation and Modification Ideas for Students Who Receive Special Education Services. PACER Center ACTion Information Sheets: PHP-c49

    Science.gov (United States)

    PACER Center, 2013

    2013-01-01

    Some students with disabilities who receive special education services need accommodations or modifications to their educational program in order to participate in the general curriculum and to be successful in school. While the Individuals with Disabilities Education Act (IDEA) and its regulations do not define accommodations or modifications,…

  3. School Accommodation and Modification Ideas for Students Who Receive Special Education Services. PACER Center ACTion Information Sheets: PHP-c49

    Science.gov (United States)

    PACER Center, 2013

    2013-01-01

    Some students with disabilities who receive special education services need accommodations or modifications to their educational program in order to participate in the general curriculum and to be successful in school. While the Individuals with Disabilities Education Act (IDEA) and its regulations do not define accommodations or modifications,…

  4. Interfacial binding and aggregation of lamin A tail domains associated with Hutchinson-Gilford progeria syndrome.

    Science.gov (United States)

    Kalinowski, Agnieszka; Yaron, Peter N; Qin, Zhao; Shenoy, Siddharth; Buehler, Markus J; Lösche, Mathias; Dahl, Kris Noel

    2014-12-01

    Hutchinson-Gilford progeria syndrome is a premature aging disorder associated with the expression of ∆50 lamin A (∆50LA), a mutant form of the nuclear structural protein lamin A (LA). ∆50LA is missing 50 amino acids from the tail domain and retains a C-terminal farnesyl group that is cleaved from the wild-type LA. Many of the cellular pathologies of HGPS are thought to be a consequence of protein-membrane association mediated by the retained farnesyl group. To better characterize the protein-membrane interface, we quantified binding of purified recombinant ∆50LA tail domain (∆50LA-TD) to tethered bilayer membranes composed of phosphatidylserine and phosphocholine using surface plasmon resonance. Farnesylated ∆50LA-TD binds to the membrane interface only in the presence of Ca(2+) or Mg(2+) at physiological ionic strength. At extremely low ionic strength, both the farnesylated and non-farnesylated forms of ∆50LA-TD bind to the membrane surface in amounts that exceed those expected for a densely packed protein monolayer. Interestingly, the wild-type LA-TD with no farnesylation also associates with membranes at low ionic strength but forms only a single layer. We suggest that electrostatic interactions are mediated by charge clusters with a net positive charge that we calculate on the surface of the LA-TDs. These studies suggest that the accumulation of ∆50LA at the inner nuclear membrane observed in cells is due to a combination of aggregation and membrane association rather than simple membrane binding; electrostatics plays an important role in mediating this association.

  5. Epigenetic involvement in Hutchinson-Gilford progeria syndrome: a mini-review.

    Science.gov (United States)

    Arancio, Walter; Pizzolanti, Giuseppe; Genovese, Swonild I; Pitrone, Maria; Giordano, Carla

    2014-01-01

    Hutchinson-Gilford progeria syndrome (HGPS) is a rare human genetic disease that leads to a severe premature ageing phenotype, caused by mutations in the LMNA gene. The LMNA gene codes for lamin-A and lamin-C proteins, which are structural components of the nuclear lamina. HGPS is usually caused by a de novo C1824T mutation that leads to the accumulation of a dominant negative form of lamin-A called progerin. Progerin also accumulates physiologically in normal ageing cells as a rare splicing form of lamin-A transcripts. From this perspective, HGPS cells seem to be good candidates for the study of the physiological mechanisms of ageing. Progerin accumulation leads to faster cellular senescence, stem cell depletion and the progeroid phenotype. Tissues of mesodermic origin are especially affected by HGPS. HGPS patients usually have a bad quality of life and, with current treatments, their life expectancy does not exceed their second decade at best. Though progerin can be expressed in almost any tissue, when death occurs, it is usually due to cardiovascular complications. In HGPS, severe epigenetic alterations have been reported. Histone-covalent modifications are radically different from control specimens, with the tendency to lose the bipartition into euchromatin and heterochromatin. This is reflected in an altered spatial compartmentalization and conformation of chromatin within the nucleus. Moreover, it seems that microRNAs and microRNA biosynthesis might play a role in HGPS. Exemplary in this connection is the suggested protective effect of miR-9 on the central nervous system of affected individuals. This mini-review will report on the state of the art of HGPS epigenetics, and there will be a discussion of how epigenetic alterations in HGPS cells can alter the cellular metabolism and lead to the systemic syndrome.

  6. Pluripotent stem cells to model Hutchinson-Gilford progeria syndrome (HGPS): Current trends and future perspectives for drug discovery.

    Science.gov (United States)

    Lo Cicero, Alessandra; Nissan, Xavier

    2015-11-01

    Progeria, or Hutchinson-Gilford progeria syndrome (HGPS), is a rare, fatal genetic disease characterized by an appearance of accelerated aging in children. This syndrome is typically caused by mutations in codon 608 (p.G608G) of the LMNA, leading to the production of a mutated form of lamin A precursor called progerin. In HGPS, progerin accumulates in cells causing progressive molecular defects, including nuclear shape abnormalities, chromatin disorganization, damage to DNA and delays in cell proliferation. Here we report how, over the past five years, pluripotent stem cells have provided new insights into the study of HGPS and opened new original therapeutic perspectives to treat the disease.

  7. Simultaneous Shoulder and Hip Dislocation in a 12-Year-Old Girl with Hutchinson-Gilford Progeria Syndrome

    Directory of Open Access Journals (Sweden)

    Shirin Mardookhpour

    2012-06-01

    Full Text Available Hutchinson-Gilford progeria syndrome (HGPS is a rare premature ageing disorder that is characterized by accelerated degenerative changes of the cutaneous, musculoskeletal and cardiovascular systems. Mean age at diagnosis is 2.9 years and generally leading to death at approximately 13 years of age due to myocardial infarction or stroke. Orthopedic manifestations of HGPS are multiple and shoulder dislocation is a rare skeletal trauma in progeria syndrome. Our patient had simultaneous shoulder and hip dislocation associated with a low energy trauma. This subject has not been reported. Treatment accomplished as close reduction under general anesthesia and immobilization.

  8. 3M: Hutchinson Plant Focuses on Heat Recovery and Cogeneration during Plan-Wide Energy-Efficiency Assessment

    Energy Technology Data Exchange (ETDEWEB)

    None

    2003-06-01

    3M performed a plant-wide energy efficiency assessment at its Hutchinson, Minnesota, plant to identify energy- and cost-saving opportunities. Assessment staff developed four separate implementation packages that represented various combinations of energy-efficiency projects involving chiller consolidation, air compressor cooling improvements, a steam turbine used for cogeneration, and a heat recovery boiler for two of the plant's thermal oxidizers. Staff estimated that the plant could save 6 million kWh/yr in electricity and more than 200,000 MMBtu/yr in natural gas and fuel oil, and avoid energy costs of more than $1 million during the first year.

  9. [Geriatric trauma centers - requirements catalog. An initiative to promote and guarantee the quality of care of elderly trauma patients receiving inpatient care].

    Science.gov (United States)

    Gogol, M; van den Heuvel, D; Lüttje, D; Püllen, R; Reingräber, A C; Schulz, R-J; Veer, A; Wittrich, A

    2014-06-01

    For the care of the elderly, specific geriatric care facilities in hospitals and specialized rehabilitation centers have been established in the last 20 years throughout Germany. In addition, trauma surgery departments in hospitals and clinics also provide comprehensive care for trauma patients. The present requirements catalog was developed with the aim to ensure the standardization and quality assurance of these care facilities. Thus, the structural basics and, in particular, the structured cooperation between geriatrics and trauma surgery are described and defined in terms of structure, process, and outcome quality. The Bundesverband Geriatrie, the Deutsche Gesellschaft für Geriatrie, and the Deutsche Gesellschaft für Gerontologie und Geriatrie offer documentation for external and internal use and evaluation of the structures and processes for certification of geriatric trauma centers. Prerequisite for certification is to meet the technical requirements defined in the requirements catalogue or documents derived from it, and proof of a quality management system according to ISO 9001.

  10. A CMOS Gm—C complex filter with a reconfigurable center and cutoff frequencies in low-IF WiMAX receivers

    Science.gov (United States)

    Xin, Cheng; Haigang, Yang; Tongqiang, Gao; Tao, Yin

    2013-07-01

    This paper presents a reconfigurable fifth-order complex Gm—C filter for different data rates in low-IF WiMAX applications. The design procedure and linearized measures to realize the complex filter are described. In order to achieve the reconfigurability of bandwidth window, the center frequency and the cutoff frequency filter are adjusted simultaneously by changing capacitor values while keeping transconductors unchanged. Also, the filter integrates an on-chip automatic frequency tuning circuit based on a PLL. Experimental results show that it has an IRR of 32 dB, a THD of -43 dB, and an input-referred noise of 21 μVrms. The chip is fabricated in 0.13 μm CMOS process, occupies 0.7 × 1 mm2, and consumes 4.8 mA current from a 1.2 V power supply.

  11. Factors associated with HIV/AIDS diagnostic disclosure to HIV infected children receiving HAART: a multi-center study in Addis Ababa, Ethiopia.

    Directory of Open Access Journals (Sweden)

    Sibhatu Biadgilign

    Full Text Available BACKGROUND: Diagnostic disclosure of HIV/AIDS to a child is becoming an increasingly common issue in clinical practice. Nevertheless, some parents and health care professionals are reluctant to inform children about their HIV infection status. The objective of this study was to identify the proportion of children who have knowledge of their serostatus and factors associated with disclosure in HIV-infected children receiving HAART in Addis Ababa, Ethiopia. METHODS: A cross-sectional study was conducted in five hospitals in Addis Ababa from February 18, 2008-April 28, 2008. The study populations were parents/caretakers and children living with HIV/AIDS who were receiving Highly Active Antiretroviral Therapy (HAART in selected hospitals in Addis Ababa. Univariate and multivariate logistic regression analysis were carried out using SPSS 12.0.1 statistical software. RESULTS: A total of 390 children/caretaker pairs were included in the study. Two hundred forty three children (62.3% were between 6-9 years of age. HIV/AIDS status was known by 68 (17.4% children, 93 (29% caretakers reported knowing the child's serostatus two years prior to our survey, 180 (46.2% respondents said that the child should be told about his/her HIV/AIDS status when he/she is older than 14 years of age. Children less than 9 years of age and those living with educated caregivers are less likely to know their results than their counterparts. Children referred from hospital's in-patient ward before attending the HIV clinic and private clinic were more likely to know their results than those from community clinic. CONCLUSION: The proportion of disclosure of HIV/AIDS diagnosis to HIV-infected children is low. Strengthening referral linkage and health education tailored to educated caregivers are recommended to increase the rate of disclosure.

  12. Implementing a Death with Dignity program at a comprehensive cancer center.

    Science.gov (United States)

    Loggers, Elizabeth Trice; Starks, Helene; Shannon-Dudley, Moreen; Back, Anthony L; Appelbaum, Frederick R; Stewart, F Marc

    2013-04-11

    The majority of Death with Dignity participants in Washington State and Oregon have received a diagnosis of terminal cancer. As more states consider legislation regarding physician-assisted death, the experience of a comprehensive cancer center may be informative. We describe the implementation of a Death with Dignity program at Seattle Cancer Care Alliance, the site of care for the Fred Hutchinson-University of Washington Cancer Consortium, a comprehensive cancer center in Seattle that serves the Pacific Northwest. Institution-level data were compared with publicly available statewide data from Oregon and Washington. A total of 114 patients inquired about our Death with Dignity program between March 5, 2009, and December 31, 2011. Of these, 44 (38.6%) did not pursue the program, and 30 (26.3%) initiated the process but either elected not to continue or died before completion. Of the 40 participants who, after counseling and upon request, received a prescription for a lethal dose of secobarbital (35.1% of the 114 patients who inquired about the program), all died, 24 after medication ingestion (60% of those obtaining prescriptions). The participants at our center accounted for 15.7% of all participants in the Death with Dignity program in Washington (255 persons) and were typically white, male, and well educated. The most common reasons for participation were loss of autonomy (97.2%), inability to engage in enjoyable activities (88.9%), and loss of dignity (75.0%). Eleven participants lived for more than 6 months after prescription receipt. Qualitatively, patients and families were grateful to receive the lethal prescription, whether it was used or not. Overall, our Death with Dignity program has been well accepted by patients and clinicians.

  13. High rates of viral suppression in a cohort of HIV-positive adults receiving ART in Ethiopian health centers irrespective of concomitant tuberculosis

    Directory of Open Access Journals (Sweden)

    Anton Reepalu

    2014-11-01

    Full Text Available Introduction: Antiretroviral therapy (ART initiation during treatment for tuberculosis (TB improves survival in HIV/TB co-infected patients. Data on ART outcome for HIV/TB co-infected patients managed in primary health care in low-income regions is limited. We compared virological suppression rates, mortality and retention in care in HIV-positive adults receiving care in five Ethiopian health centres with regard to TB co-infection. Materials and Methods: HIV-positive ART-naïve adults eligible for ART initiation were prospectively recruited from October 2011 until March 2013. At inclusion, all patients submitted sputum for microbiological TB testing (smear microscopy, liquid culture and PCR. Virological suppression rates after six months of ART (VS; viral load <40 and <400 copies/mL with regard to TB status was the primary outcome. The impact of HIV/TB co-infection on VS rates was determined by multivariate regression analysis. Mortality and retention in care were analyzed by proportional hazard models. Results: Among 812 participants (TB 158; non-TB 654, 678 started ART during the follow-up period (TB 135; non-TB 543. Median CD4 cell counts at ART initiation were 161 cells/µL (interquartile range [IQR], 98–243 and 184 (IQR, 118–256 for TB and non-TB patients, respectively (p=0.05. No difference in retention in care between TB and non-TB patients was observed during follow-up; 25 (3.7% patients died and 17 (2.5% were lost to follow-up (p=0.30 and p=0.83, respectively. Overall rates of VS at six months were 72.1% (<40 copies/mL and 88.7% (<400 copies/mL, with similar results for subjects with and without TB co-infection (<40 copies/mL: 65/92 (70.7% vs. 304/420 (72.4%, p=0.74; <400 copies/mL: 77/92 (83.7% vs. 377/420 (89.8%, p=0.10, respectively. CD4 cell count increase during treatment was 87 (IQR, 26–178 and 103 cells/µL (IQR, 38–173 for TB and non-TB patients, respectively, with no significant difference between the two groups (p=0

  14. Importance of molecular cell biology investigations in human medicine in the story of the Hutchinson-Gilford progeria syndrome.

    Science.gov (United States)

    Raška, Ivan

    2010-09-01

    Ranged among laminopathies, Hutchinson-Gilford progeria syndrome is a syndrome that involves premature aging, leading usually to death at the age between 10 to 14 years predominatly due to a myocardial infarction or a stroke. In the lecture I shall overview the importance of molecular cell biology investigations that led to the discovery of the basic mechanism standing behind this rare syndrome. The genetic basis in most cases is a mutation at the nucleotide position 1824 of the lamin A gene. At this position, cytosine is substituted for thymine so that a cryptic splice site within the precursor mRNA for lamin A is generated. This results in a production of abnormal lamin A, termed progerin, its presence in cells having a deleterious dominant effect. Depending on the cell type and tissue, progerin induces a pleiotropy of defects that vary in different tissues. The present endeavour how to challenge this terrible disease will be also mentioned.

  15. Accumulation of mutant lamin A causes progressive changes in nuclear architecture in Hutchinson-Gilford progeria syndrome.

    Science.gov (United States)

    Goldman, Robert D; Shumaker, Dale K; Erdos, Michael R; Eriksson, Maria; Goldman, Anne E; Gordon, Leslie B; Gruenbaum, Yosef; Khuon, Satya; Mendez, Melissa; Varga, Renée; Collins, Francis S

    2004-06-15

    Hutchinson-Gilford progeria syndrome (HGPS) is a premature aging disorder, commonly caused by a point mutation in the lamin A gene that results in a protein lacking 50 aa near the C terminus, denoted LADelta50. Here we show by light and electron microscopy that HGPS is associated with significant changes in nuclear shape, including lobulation of the nuclear envelope, thickening of the nuclear lamina, loss of peripheral heterochromatin, and clustering of nuclear pores. These structural defects worsen as HGPS cells age in culture, and their severity correlates with an apparent increase in LADelta50. Introduction of LADelta50 into normal cells by transfection or protein injection induces the same changes. We hypothesize that these alterations in nuclear structure are due to a concentration-dependent dominant-negative effect of LADelta50, leading to the disruption of lamin-related functions ranging from the maintenance of nuclear shape to regulation of gene expression and DNA replication.

  16. Induced pluripotent stem cells reveal functional differences between drugs currently investigated in patients with hutchinson-gilford progeria syndrome.

    Science.gov (United States)

    Blondel, Sophie; Jaskowiak, Anne-Laure; Egesipe, Anne-Laure; Le Corf, Amelie; Navarro, Claire; Cordette, Véronique; Martinat, Cécile; Laabi, Yacine; Djabali, Karima; de Sandre-Giovannoli, Annachiara; Levy, Nicolas; Peschanski, Marc; Nissan, Xavier

    2014-04-01

    Hutchinson-Gilford progeria syndrome is a rare congenital disease characterized by premature aging in children. Identification of the mutation and related molecular mechanisms has rapidly led to independent clinical trials testing different marketed drugs with a preclinically documented impact on those mechanisms. However, the extensive functional effects of those drugs remain essentially unexplored. We have undertaken a systematic comparative study of the three main treatments currently administered or proposed to progeria-affected children, namely, a farnesyltransferase inhibitor, the combination of an aminobisphosphonate and a statin (zoledronate and pravastatin), and the macrolide antibiotic rapamycin. This work was based on the assumption that mesodermal stem cells, which are derived from Hutchinson-Gilford progeria syndrome-induced pluripotent stem cells expressing major defects associated with the disease, may be instrumental to revealing such effects. Whereas all three treatments significantly improved misshapen cell nuclei typically associated with progeria, differences were observed in terms of functional improvement in prelamin A farnesylation, progerin expression, defective cell proliferation, premature osteogenic differentiation, and ATP production. Finally, we have evaluated the effect of the different drug combinations on this cellular model. This study revealed no additional benefit compared with single-drug treatments, whereas a cytostatic effect equivalent to that of a farnesyltransferase inhibitor alone was systematically observed. Altogether, these results reveal the complexity of the modes of action of different drugs, even when they have been selected on the basis of a similar mechanistic hypothesis, and underscore the use of induced pluripotent stem cell derivatives as a critical and powerful tool for standardized, comparative pharmacological studies.

  17. Reductions in Hard Drug Use Among Homeless Youth Receiving a Strength-Based Outreach Intervention: Comparing the Long-Term Effects of Shelter Linkage Versus Drop-in Center Linkage.

    Science.gov (United States)

    Guo, Xiamei; Slesnick, Natasha

    2017-06-07

    The current study sought to test hard drug use outcomes for youth receiving a strengths-based outreach and advocacy intervention that linked youth to either a shelter or a drop-in center. Homeless youth (14-24 years old) were engaged by research assistants (RAs) at soup kitchens, parks, libraries, and other locations that homeless youth were known to frequent. Youth were randomly assigned to receive six months of advocacy that focused on linking youth to a drop-in center (n = 40) or to a crisis shelter (n = 39). Follow-up assessments were conducted at 3, 6, and 9 months post-baseline. Hard drug use over time was the main outcome. Intervention condition and service connection were used as predictors for the baseline level and the slope of change in hard drug use over time. Data analysis was conducted with Bernoulli Hierarchical Generalized Linear Modeling in HLM7. The current study found that those who were in the drop-in linkage condition exhibited a greater reduction in their odds of using hard drugs during the follow-up points than their counterparts in the shelter linkage condition. And finally, those who utilized services more often during the follow-ups were those who exhibited less hard drug use at baseline and less reduction in their odds of using hard drugs. This study suggests that drop-in centers, which are often characterized by low-demand programming and few behavioral restrictions, are effective for addressing hard drug use among homeless youth.

  18. Distribution center

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    Distribution center is a logistics link fulfill physical distribution as its main functionGenerally speaking, it's a large and hiahly automated center destined to receive goods from various plants and suppliers,take orders,fill them efficiently,and deliver goods to customers as quickly as possible.

  19. A single-center evaluation of the risk for colonization or bacteremia with piperacillin-tazobactam- and cefepime-resistant bacteria in patients with acute leukemia receiving fluoroquinolone prophylaxis.

    Science.gov (United States)

    Nguyen, A D; Heil, E L; Patel, N K; Duffy, A; Gilmore, S

    2016-04-01

    Fluoroquinolone prophylaxis is indicated to prevent neutropenic fever in patients with acute leukemia. However, fluoroquinolone use has been associated with development of multi-drug-resistant Pseudomonas aeruginosa and extended spectrum β-lactamase producing gram-negative bacilli. Due to a presumed risk of multi-drug resistance associated with fluoroquinolone prophylaxis, patients admitted to our hospital with neutropenic fever receive empiric carbapenem therapy until cultures are negative for 72 h or identification of an organism. Our study seeks to identify the incidence of multi-drug-resistant organism colonization and bacteremia among patients who receive fluoroquinolone prophylaxis and to evaluate duration of empiric carbapenem therapy. A retrospective review of adult patients with acute leukemia receiving a fluoroquinolone as outpatient infection prophylaxis, admitted to our tertiary cancer center for treatment of neutropenic fever was completed. Surveillance and blood cultures were reviewed for antibiotic resistance. Duration of empiric carbapenem therapy was reviewed. One hundred patients and 177 admissions for neutropenic fever were included. Six patients harbored a piperacillin-tazobactam-resistant organism found during routine surveillance. Among these patients, two bacteremias were identified, one of which was a piperacillin-tazobactam-resistant organism. Five bacteremias were identified among 83 patients with negative surveillance cultures. Among the bloodstream infections, five organisms isolated were fluoroquinolone resistant. No cefepime-resistant organism was isolated on surveillance or bloodstream cultures. Adherence to the institution guideline of narrowing antibiotics after 72 h of negative cultures occurred in only 13% of neutropenic fever cases. The average duration of carbapenem therapy in 177 neutropenic fever episodes was 4.4 days. Our findings show that among our patient population, there is a low risk of bacteremia with a

  20. Chemical screening identifies ROCK as a target for recovering mitochondrial function in Hutchinson-Gilford progeria syndrome.

    Science.gov (United States)

    Kang, Hyun Tae; Park, Joon Tae; Choi, Kobong; Choi, Hyo Jei Claudia; Jung, Chul Won; Kim, Gyu Ree; Lee, Young-Sam; Park, Sang Chul

    2017-03-19

    Hutchinson-Gilford progeria syndrome (HGPS) constitutes a genetic disease wherein an aging phenotype manifests in childhood. Recent studies indicate that reactive oxygen species (ROS) play important roles in HGPS phenotype progression. Thus, pharmacological reduction in ROS levels has been proposed as a potentially effective treatment for patient with this disorder. In this study, we performed high-throughput screening to find compounds that could reduce ROS levels in HGPS fibroblasts and identified rho-associated protein kinase (ROCK) inhibitor (Y-27632) as an effective agent. To elucidate the underlying mechanism of ROCK in regulating ROS levels, we performed a yeast two-hybrid screen and discovered that ROCK1 interacts with Rac1b. ROCK activation phosphorylated Rac1b at Ser71 and increased ROS levels by facilitating the interaction between Rac1b and cytochrome c. Conversely, ROCK inactivation with Y-27632 abolished their interaction, concomitant with ROS reduction. Additionally, ROCK activation resulted in mitochondrial dysfunction, whereas ROCK inactivation with Y-27632 induced the recovery of mitochondrial function. Furthermore, a reduction in the frequency of abnormal nuclear morphology and DNA double-strand breaks was observed along with decreased ROS levels. Thus, our study reveals a novel mechanism through which alleviation of the HGPS phenotype is mediated by the recovery of mitochondrial function upon ROCK inactivation.

  1. Replication Factor C1, the Large Subunit of Replication Factor C, Is Proteolytically Truncated in Hutchinson-Gilford Progeria Syndrome

    Science.gov (United States)

    Tang, Hui; Hilton, Benjamin; Musich, Phillip R.; Fang, Ding Zhi; Zou, Yue

    2011-01-01

    Hutchinson-Gilford progeria syndrome (HGPS) is a rare genetic disorder due to a LMNA gene mutation which produces a mutant lamin A protein (progerin). Progerin also has been correlated to physiological aging and related diseases. However, how progerin causes the progeria remains unknown. Here we report that the large subunit (RFC1) of replication factor C is cleaved in HGPS cells, leading to the production of a truncated RFC1 of ~75 kDa which appears to be defective in loading PCNA and pol δ onto DNA for replication. Interestingly, the cleavage can be inhibited by a serine protease inhibitor, suggesting that RFC1 is cleaved by a serine protease. Due to the crucial role of RFC in DNA replication our findings provide a mechanistic interpretation for the observed replicative arrest and premature aging phenotypes of HPGS, and may lead to novel strategies in HGPS treatment. Furthermore, this unique truncated form of RFC1 may serve as a potential marker for HGPS. PMID:22168243

  2. Progerin impairs chromosome maintenance by depleting CENP-F from metaphase kinetochores in Hutchinson-Gilford progeria fibroblasts.

    Science.gov (United States)

    Eisch, Veronika; Lu, Xiang; Gabriel, Diana; Djabali, Karima

    2016-04-26

    Hutchinson-Gilford progeria syndrome (HGPS, OMIM 176670) is a rare premature aging disorder that leads to death at an average age of 14.7 years due to myocardial infarction or stroke. The most common mutation in HGPS is at position G608G (GGC>GGT) within exon 11 of the LMNA gene. This mutation results in the deletion of 50 amino acids at the carboxyl-terminal tail of prelamin A, producing a truncated farnesylated protein called progerin. Lamins play important roles in the organization and structure of the nucleus. The nuclear build-up of progerin causes severe morphological and functional changes in interphase HGPS cells. In this study, we investigated whether progerin elicits spatiotemporal deviations in mitotic processes in HGPS fibroblasts. We analyzed the nuclear distribution of endogenous progerin during mitosis in relation to components of the nuclear lamina, nuclear envelope (NE) and nuclear pores. We found that progerin caused defects in chromosome segregation as early as metaphase, delayed NE reformation and trapped lamina components and inner NE proteins in the endoplasmic reticulum at the end of mitosis. Progerin displaced the centromere protein F (CENP-F) from metaphase chromosome kinetochores, which caused increased chromatin lagging, binucleated cells and genomic instability. This accumulation of progerin-dependent defects with each round of mitosis predisposes cells to premature senescence.

  3. Defective lamin A-Rb signaling in Hutchinson-Gilford Progeria Syndrome and reversal by farnesyltransferase inhibition.

    Directory of Open Access Journals (Sweden)

    Jackleen Marji

    Full Text Available Hutchinson-Gilford Progeria Syndrome (HGPS is a rare premature aging disorder caused by a de novo heterozygous point mutation G608G (GGC>GGT within exon 11 of LMNA gene encoding A-type nuclear lamins. This mutation elicits an internal deletion of 50 amino acids in the carboxyl-terminus of prelamin A. The truncated protein, progerin, retains a farnesylated cysteine at its carboxyl terminus, a modification involved in HGPS pathogenesis. Inhibition of protein farnesylation has been shown to improve abnormal nuclear morphology and phenotype in cellular and animal models of HGPS. We analyzed global gene expression changes in fibroblasts from human subjects with HGPS and found that a lamin A-Rb signaling network is a major defective regulatory axis. Treatment of fibroblasts with a protein farnesyltransferase inhibitor reversed the gene expression defects. Our study identifies Rb as a key factor in HGPS pathogenesis and suggests that its modulation could ameliorate premature aging and possibly complications of physiological aging.

  4. Hutchinson-Gilford progeria syndrome alters nuclear shape and reduces cell motility in three dimensional model substrates.

    Science.gov (United States)

    Booth-Gauthier, Elizabeth A; Du, Vicard; Ghibaudo, Marion; Rape, Andrew D; Dahl, Kris Noel; Ladoux, Benoit

    2013-03-01

    Cell migration through tight interstitial spaces in three dimensional (3D) environments impacts development, wound healing and cancer metastasis and is altered by the aging process. The stiffness of the extracellular matrix (ECM) increases with aging and affects the cells and cytoskeletal processes involved in cell migration. However, the nucleus, which is the largest and densest organelle, has not been widely studied during cell migration through the ECM. Additionally, the nucleus is stiffened during the aging process through the accumulation of a mutant nucleoskeleton protein lamin A, progerin. By using microfabricated substrates to mimic the confined environment of surrounding tissues, we characterized nuclear movements and deformation during cell migration into micropillars where interspacing can be tuned to vary nuclear confinement. Cell motility decreased with decreased micropillar (μP) spacing and correlated with increased dysmorphic shapes of nuclei. We examined the effects of increased nuclear stiffness which correlates with cellular aging by studying Hutchinson-Gilford progeria syndrome cells which are known to accumulate progerin. With the expression of progerin, cells showed a threshold response to decreased μP spacing. Cells became trapped in the close spacing, possibly from visible micro-defects in the nucleoskeleton induced by cell crawling through the μP and from reduced force generation, measured independently. We suggest that ECM changes during aging could be compounded by the increasing stiffness of the nucleus and thus changes in cell migration through 3D tissues.

  5. Rapamycin activates autophagy in Hutchinson-Gilford progeria syndrome: implications for normal aging and age-dependent neurodegenerative disorders.

    Science.gov (United States)

    Graziotto, John J; Cao, Kan; Collins, Francis S; Krainc, Dimitri

    2012-01-01

    While rapamycin has been in use for years in transplant patients as an antirejection drug, more recently it has shown promise in treating diseases of aging, such as neurodegenerative disorders and atherosclerosis. We recently reported that rapamycin reverses the cellular phenotype of fibroblasts from children with the premature aging disease Hutchinson-Gilford progeria syndrome (HGPS). We found that the causative aberrant protein, progerin, was cleared through autophagic mechanisms when the cells were treated with rapamycin, suggesting a new potential treatment for HGPS. Recent evidence shows that progerin is also present in aged tissues of healthy individuals, suggesting that progerin may contribute to physiological aging. While it is intriguing to speculate that rapamycin may affect normal aging in humans, as it does in lower organisms, it will be important to identify safer analogues of rapamycin for chronic treatments in humans in order to minimize toxicity. In addition to its role in HGPS and normal aging, we discuss the potential of rapamycin for the treatment of age-dependent neurodegenerative diseases.

  6. Farnesyltransferase inhibitor treatment restores chromosome territory positions and active chromosome dynamics in Hutchinson-Gilford progeria syndrome cells

    Science.gov (United States)

    2011-01-01

    Background Hutchinson-Gilford progeria syndrome (HGPS) is a premature ageing syndrome that affects children leading to premature death, usually from heart infarction or strokes, making this syndrome similar to normative ageing. HGPS is commonly caused by a mutation in the A-type lamin gene, LMNA (G608G). This leads to the expression of an aberrant truncated lamin A protein, progerin. Progerin cannot be processed as wild-type pre-lamin A and remains farnesylated, leading to its aberrant behavior during interphase and mitosis. Farnesyltransferase inhibitors prevent the accumulation of farnesylated progerin, producing a less toxic protein. Results We have found that in proliferating fibroblasts derived from HGPS patients the nuclear location of interphase chromosomes differs from control proliferating cells and mimics that of control quiescent fibroblasts, with smaller chromosomes toward the nuclear interior and larger chromosomes toward the nuclear periphery. For this study we have treated HGPS fibroblasts with farnesyltransferase inhibitors and analyzed the nuclear location of individual chromosome territories. We have found that after exposure to farnesyltransferase inhibitors mis-localized chromosome territories were restored to a nuclear position akin to chromosomes in proliferating control cells. Furthermore, not only has this treatment afforded chromosomes to be repositioned but has also restored the machinery that controls their rapid movement upon serum removal. This machinery contains nuclear myosin 1β, whose distribution is also restored after farnesyltransferase inhibitor treatment of HGPS cells. Conclusions This study not only progresses the understanding of genome behavior in HGPS cells but demonstrates that interphase chromosome movement requires processed lamin A. PMID:21838864

  7. New Lmna knock-in mice provide a molecular mechanism for the 'segmental aging' in Hutchinson-Gilford progeria syndrome.

    Science.gov (United States)

    Jung, Hea-Jin; Tu, Yiping; Yang, Shao H; Tatar, Angelica; Nobumori, Chika; Wu, Daniel; Young, Stephen G; Fong, Loren G

    2014-03-15

    Lamins A and C (products of the LMNA gene) are found in roughly equal amounts in peripheral tissues, but the brain produces mainly lamin C and little lamin A. In HeLa cells and fibroblasts, the expression of prelamin A (the precursor to lamin A) can be reduced by miR-9, but the relevance of those cell culture studies to lamin A regulation in the brain was unclear. To address this issue, we created two new Lmna knock-in alleles, one (Lmna(PLAO-5NT)) with a 5-bp mutation in a predicted miR-9 binding site in prelamin A's 3' UTR, and a second (Lmna(PLAO-UTR)) in which prelamin A's 3' UTR was replaced with lamin C's 3' UTR. Neither allele had significant effects on lamin A levels in peripheral tissues; however, both substantially increased prelamin A transcript levels and lamin A protein levels in the cerebral cortex and the cerebellum. The increase in lamin A expression in the brain was more pronounced with the Lmna(PLAO-UTR) allele than with the Lmna(PLAO-5NT) allele. With both alleles, the increased expression of prelamin A transcripts and lamin A protein was greater in the cerebral cortex than in the cerebellum. Our studies demonstrate the in vivo importance of prelamin A's 3' UTR and its miR-9 binding site in regulating lamin A expression in the brain. The reduced expression of prelamin A in the brain likely explains why children with Hutchinson-Gilford progeria syndrome (a progeroid syndrome caused by a mutant form of prelamin A) are spared from neurodegenerative disease.

  8. Electronic warfare receivers and receiving systems

    CERN Document Server

    Poisel, Richard A

    2014-01-01

    Receivers systems are considered the core of electronic warfare (EW) intercept systems. Without them, the fundamental purpose of such systems is null and void. This book considers the major elements that make up receiver systems and the receivers that go in them.This resource provides system design engineers with techniques for design and development of EW receivers for modern modulations (spread spectrum) in addition to receivers for older, common modulation formats. Each major module in these receivers is considered in detail. Design information is included as well as performance tradeoffs o

  9. The Defective Nuclear Lamina in Hutchinson-Gilford Progeria Syndrome Disrupts the Nucleocytoplasmic Ran Gradient and Inhibits Nuclear Localization of Ubc9▿

    Science.gov (United States)

    Kelley, Joshua B.; Datta, Sutirtha; Snow, Chelsi J.; Chatterjee, Mandovi; Ni, Li; Spencer, Adam; Yang, Chun-Song; Cubeñas-Potts, Caelin; Matunis, Michael J.; Paschal, Bryce M.

    2011-01-01

    The mutant form of lamin A responsible for the premature aging disease Hutchinson-Gilford progeria syndrome (termed progerin) acts as a dominant negative protein that changes the structure of the nuclear lamina. How the perturbation of the nuclear lamina in progeria is transduced into cellular changes is undefined. Using patient fibroblasts and a variety of cell-based assays, we determined that progerin expression in Hutchinson-Gilford progeria syndrome inhibits the nucleocytoplasmic transport of several factors with key roles in nuclear function. We found that progerin reduces the nuclear/cytoplasmic concentration of the Ran GTPase and inhibits the nuclear localization of Ubc9, the sole E2 for SUMOylation, and of TPR, the nucleoporin that forms the basket on the nuclear side of the nuclear pore complex. Forcing the nuclear localization of Ubc9 in progerin-expressing cells rescues the Ran gradient and TPR import, indicating that these pathways are linked. Reducing nuclear SUMOylation decreases the nuclear mobility of the Ran nucleotide exchange factor RCC1 in vivo, and the addition of SUMO E1 and E2 promotes the dissociation of RCC1 and Ran from chromatin in vitro. Our data suggest that the cellular effects of progerin are transduced, at least in part, through reduced function of the Ran GTPase and SUMOylation pathways. PMID:21670151

  10. Blocking farnesylation of the prelamin A variant in Hutchinson-Gilford progeria syndrome alters the distribution of A-type lamins

    Science.gov (United States)

    Wang, Yuexia; Ӧstlund, Cecilia; Choi, Jason C.; Swayne, Theresa C.; Gundersen, Gregg G.; Worman, Howard J.

    2012-01-01

    Mutations in the lamin A/C gene that cause Hutchinson-Gilford progeria syndrome lead to expression of a truncated, permanently farnesylated prelamin A variant called progerin. Blocking farnesylation leads to an improvement in the abnormal nuclear morphology observed in cells expressing progerin, which is associated with a re-localization of the variant protein from the nuclear envelope to the nuclear interior. We now show that a progerin construct that cannot be farnesylated is localized primarily in intranuclear foci and that its diffusional mobility is significantly greater than that of farnesylated progerin localized predominantly at the nuclear envelope. Expression of non-farnesylated progerin in transfected cells leads to a redistribution of lamin A and lamin C away from the nuclear envelope into intranuclear foci but does not significantly affect the localization of endogenous lamin B1 at nuclear envelope. There is a similar redistribution of lamin A and lamin C into intranuclear foci in transfected cells expressing progerin in which protein farnesylation is blocked by treatment with a protein farnesyltransferase inhibitor. Blocking farnesylation of progerin can lead to a redistribution of normal A-type lamins away from the inner nuclear envelope. This may have implications for using drugs that block protein prenylation to treat children with Hutchinson-Gilford progeria syndrome. These findings also provide additional evidence that A-type and B-type lamins can form separate microdomains within the nucleus. PMID:22895092

  11. The defective nuclear lamina in Hutchinson-gilford progeria syndrome disrupts the nucleocytoplasmic Ran gradient and inhibits nuclear localization of Ubc9.

    Science.gov (United States)

    Kelley, Joshua B; Datta, Sutirtha; Snow, Chelsi J; Chatterjee, Mandovi; Ni, Li; Spencer, Adam; Yang, Chun-Song; Cubeñas-Potts, Caelin; Matunis, Michael J; Paschal, Bryce M

    2011-08-01

    The mutant form of lamin A responsible for the premature aging disease Hutchinson-Gilford progeria syndrome (termed progerin) acts as a dominant negative protein that changes the structure of the nuclear lamina. How the perturbation of the nuclear lamina in progeria is transduced into cellular changes is undefined. Using patient fibroblasts and a variety of cell-based assays, we determined that progerin expression in Hutchinson-Gilford progeria syndrome inhibits the nucleocytoplasmic transport of several factors with key roles in nuclear function. We found that progerin reduces the nuclear/cytoplasmic concentration of the Ran GTPase and inhibits the nuclear localization of Ubc9, the sole E2 for SUMOylation, and of TPR, the nucleoporin that forms the basket on the nuclear side of the nuclear pore complex. Forcing the nuclear localization of Ubc9 in progerin-expressing cells rescues the Ran gradient and TPR import, indicating that these pathways are linked. Reducing nuclear SUMOylation decreases the nuclear mobility of the Ran nucleotide exchange factor RCC1 in vivo, and the addition of SUMO E1 and E2 promotes the dissociation of RCC1 and Ran from chromatin in vitro. Our data suggest that the cellular effects of progerin are transduced, at least in part, through reduced function of the Ran GTPase and SUMOylation pathways.

  12. Transgene silencing of the Hutchinson-Gilford progeria syndrome mutation results in a reversible bone phenotype, whereas resveratrol treatment does not show overall beneficial effects

    DEFF Research Database (Denmark)

    Strandgren, Charlotte; Nasser, Hasina Abdul; McKenna, Tomás

    2015-01-01

    Hutchinson-Gilford progeria syndrome (HGPS) is a rare premature aging disorder that is most commonly caused by a de novo point mutation in exon 11 of the LMNA gene, c.1824C>T, which results in an increased production of a truncated form of lamin A known as progerin. In this study, we used a mouse...... model to study the possibility of recovering from HGPS bone disease upon silencing of the HGPS mutation, and the potential benefits from treatment with resveratrol. We show that complete silencing of the transgenic expression of progerin normalized bone morphology and mineralization already after 7...... weeks. The improvements included lower frequencies of rib fractures and callus formation, an increased number of osteocytes in remodeled bone, and normalized dentinogenesis. The beneficial effects from resveratrol treatment were less significant and to a large extent similar to mice treated with sucrose...

  13. Exposing the Data Center

    OpenAIRE

    Sergejev, Ivan

    2014-01-01

    Given the rapid growth in the importance of the Internet, data centers - the buildings that store information on the web - are quickly becoming the most critical infrastructural objects in the world. However, so far they have received very little, if any, architectural attention. This thesis proclaims data centers to be the 'churches' of the digital society and proposes a new type of a publicly accessible data center. The thesis starts with a brief overview of the history of data centers ...

  14. Highly Sensitive Optical Receivers

    CERN Document Server

    Schneider, Kerstin

    2006-01-01

    Highly Sensitive Optical Receivers primarily treats the circuit design of optical receivers with external photodiodes. Continuous-mode and burst-mode receivers are compared. The monograph first summarizes the basics of III/V photodetectors, transistor and noise models, bit-error rate, sensitivity and analog circuit design, thus enabling readers to understand the circuits described in the main part of the book. In order to cover the topic comprehensively, detailed descriptions of receivers for optical data communication in general and, in particular, optical burst-mode receivers in deep-sub-µm CMOS are presented. Numerous detailed and elaborate illustrations facilitate better understanding.

  15. Low complexity MIMO receivers

    CERN Document Server

    Bai, Lin; Yu, Quan

    2014-01-01

    Multiple-input multiple-output (MIMO) systems can increase the spectral efficiency in wireless communications. However, the interference becomes the major drawback that leads to high computational complexity at both transmitter and receiver. In particular, the complexity of MIMO receivers can be prohibitively high. As an efficient mathematical tool to devise low complexity approaches that mitigate the interference in MIMO systems, lattice reduction (LR) has been widely studied and employed over the last decade. The co-authors of this book are world's leading experts on MIMO receivers, and here they share the key findings of their research over years. They detail a range of key techniques for receiver design as multiple transmitted and received signals are available. The authors first introduce the principle of signal detection and the LR in mathematical aspects. They then move on to discuss the use of LR in low complexity MIMO receiver design with respect to different aspects, including uncoded MIMO detection...

  16. Delphi Accounts Receivable Module -

    Data.gov (United States)

    Department of Transportation — Delphi accounts receivable module contains the following data elements, but are not limited to customer information, cash receipts, line of accounting details, bill...

  17. On Cultivation of Metaphoric Competence and Critical Thinking in ESP Course--- Thoughts on Course Design Model of Hutchinson & Waters%ESP 教学中隐喻能力与批判思维的培养--基于Hutchinson & Waters课程设计模型的思考

    Institute of Scientific and Technical Information of China (English)

    刘佳丽

    2015-01-01

    T he metaphoric competence and critical thinking are closely related to the comprehensive devel‐opment of learners .However ,little attention has been paid to postgraduate students of English major in ESP course .Based on the course design model by Hutchinson and Waters ,this paper attempts to ana‐lyze four segments ,identifying learners ,analyzing learning situations and target situations ,w riting syl‐labus and materials ,evaluation ,for bringing up some suggestions to develop learners’ metaphoric com‐petence and critical thinking ,thus offering reference to ESP course reform of high education English ma‐jor postgraduates .%隐喻能力与批判思维关系到学习者的全面发展,而长期以来英语专业研究生ES P教学对该能力培养重视不够。根据Hutchinson&Waters课程设计模式,分别从学习者鉴定、学习情景与目标情景、教学大纲设计与教材选择、课程评估四个环节对英语专业研究生ES P教学展开分析,为培养学习者隐喻能力与批判性思维提出可行性建议,对高校英语专业硕士研究生ES P教学课程改革具有参考价值。

  18. Defective DSB repair correlates with abnormal nuclear morphology and is improved with FTI treatment in Hutchinson-Gilford progeria syndrome fibroblasts

    Energy Technology Data Exchange (ETDEWEB)

    Constantinescu, Dan [Department of Cell Biology-Physiology, University of Pittsburgh, Pittsburgh, PA 15260 (United States); Pittsburgh Development Center, Magee-Women' s Research Institute, University of Pittsburgh, Pittsburgh, PA 15260 (United States); Csoka, Antonei B. [Division of Geriatrics, Department of Medicine, University of Pittsburgh Medical Center, Pittsburgh, PA 15260 (United States); Navara, Christopher S. [Division of Developmental and Regenerative Medicine, Department of Obstetrics, Gynecology, and Reproductive Sciences, University of Pittsburgh, Pittsburgh, PA 15260 (United States); Pittsburgh Development Center, Magee-Women' s Research Institute, University of Pittsburgh, Pittsburgh, PA 15260 (United States); Schatten, Gerald P., E-mail: schattengp@upmc.edu [Division of Developmental and Regenerative Medicine, Department of Obstetrics, Gynecology, and Reproductive Sciences, University of Pittsburgh, Pittsburgh, PA 15260 (United States); Department of Cell Biology-Physiology, University of Pittsburgh, Pittsburgh, PA 15260 (United States); Pittsburgh Development Center, Magee-Women' s Research Institute, University of Pittsburgh, Pittsburgh, PA 15260 (United States)

    2010-10-15

    Impaired DSB repair has been implicated as a molecular mechanism contributing to the accelerating aging phenotype in Hutchinson-Gilford progeria syndrome (HGPS), but neither the extent nor the cause of the repair deficiency has been fully elucidated. Here we perform a quantitative analysis of the steady-state number of DSBs and the repair kinetics of ionizing radiation (IR)-induced DSBs in HGPS cells. We report an elevated steady-state number of DSBs and impaired repair of IR-induced DSBs, both of which correlated strongly with abnormal nuclear morphology. We recreated the HGPS cellular phenotype in human coronary artery endothelial cells for the first time by lentiviral transduction of GFP-progerin, which also resulted in impaired repair of IR-induced DSBs, and which correlated with abnormal nuclear morphology. Farnesyl transferase inhibitor (FTI) treatment improved the repair of IR-induced DSBs, but only in HGPS cells whose nuclear morphology was also normalized. Interestingly, FTI treatment did not result in a statistically significant reduction in the higher steady-state number of DSBs. We also report a delay in localization of phospho-NBS1 and MRE11, MRN complex repair factors necessary for homologous recombination (HR) repair, to DSBs in HGPS cells. Our results demonstrate a correlation between nuclear structural abnormalities and the DSB repair defect, suggesting a mechanistic link that may involve delayed repair factor localization to DNA damage. Further, our results show that similar to other HGPS phenotypes, FTI treatment has a beneficial effect on DSB repair.

  19. Naïve adult stem cells from patients with Hutchinson-Gilford progeria syndrome express low levels of progerin in vivo

    Science.gov (United States)

    Wenzel, Vera; Roedl, Daniela; Gabriel, Diana; Gordon, Leslie B.; Herlyn, Meenhard; Schneider, Reinhard; Ring, Johannes; Djabali, Karima

    2012-01-01

    Summary Hutchinson-Gilford progeria syndrome (HGPS, OMIM 176670) is a rare disorder characterized by segmental accelerated aging and early death from coronary artery disease or stroke. Nearly 90% of HGPS sufferers carry a G608G mutation within exon 11 of LMNA, producing a truncated form of prelamin A, referred to as “progerin”. Here, we report the isolation of naïve multipotent skin-derived precursor (SKP) cells from dermal fibroblast cultures from HGPS donors. These cells form spheres and express the neural crest marker, nestin, in addition to the multipotent markers, OCT4, Sox2, Nanog and TG30; these cells can self-renew and differentiate into smooth muscle cells (SMCs) and fibroblasts. The SMCs derived from the HGPS-SKPs accumulate nuclear progerin with increasing passages. A subset of the HGPS-naïve SKPs express progerin in vitro and in situ in HGPS skin sections. This is the first in vivo evidence that progerin is produced in adult stem cells, and implies that this protein could induce stem cells exhaustion as a mechanism contributing to aging. Our study provides a basis on which to explore therapeutic applications for HGPS stem cells and opens avenues for investigating the pathogenesis of other genetic diseases. PMID:23213444

  20. Correlated alterations in genome organization, histone methylation, and DNA–lamin A/C interactions in Hutchinson-Gilford progeria syndrome

    Science.gov (United States)

    McCord, Rachel Patton; Nazario-Toole, Ashley; Zhang, Haoyue; Chines, Peter S.; Zhan, Ye; Erdos, Michael R.; Collins, Francis S.; Dekker, Job; Cao, Kan

    2013-01-01

    Hutchinson-Gilford progeria syndrome (HGPS) is a premature aging disease that is frequently caused by a de novo point mutation at position 1824 in LMNA. This mutation activates a cryptic splice donor site in exon 11, and leads to an in-frame deletion within the prelamin A mRNA and the production of a dominant-negative lamin A protein, known as progerin. Here we show that primary HGPS skin fibroblasts experience genome-wide correlated alterations in patterns of H3K27me3 deposition, DNA-lamin A/C associations, and, at late passages, genome-wide loss of spatial compartmentalization of active and inactive chromatin domains. We further demonstrate that the H3K27me3 changes associate with gene expression alterations in HGPS cells. Our results support a model that the accumulation of progerin in the nuclear lamina leads to altered H3K27me3 marks in heterochromatin, possibly through the down-regulation of EZH2, and disrupts heterochromatin–lamina interactions. These changes may result in transcriptional misregulation and eventually trigger the global loss of spatial chromatin compartmentalization in late passage HGPS fibroblasts. PMID:23152449

  1. Expression of the Hutchinson-Gilford Progeria Mutation during Osteoblast Development Results in Loss of Osteocytes, Irregular Mineralization, and Poor Biomechanical Properties*

    Science.gov (United States)

    Schmidt, Eva; Nilsson, Ola; Koskela, Antti; Tuukkanen, Juha; Ohlsson, Claes; Rozell, Björn; Eriksson, Maria

    2012-01-01

    Hutchinson-Gilford progeria syndrome (HGPS) is a very rare genetic disorder that is characterized by multiple features of premature aging and largely affects tissues of mesenchymal origin. In this study, we describe the development of a tissue-specific mouse model that overexpresses the most common HGPS mutation (LMNA, c.1824C>T, p.G608G) in osteoblasts. Already at the age of 5 weeks, HGPS mutant mice show growth retardation, imbalanced gait and spontaneous fractures. Histopathological examination revealed an irregular bone structure, characterized by widespread loss of osteocytes, defects in mineralization, and a hypocellular red bone marrow. Computerized tomography analysis demonstrated impaired skeletal geometry and altered bone structure. The skeletal defects, which resemble the clinical features reported for bone disease in HGPS patients, was associated with an abnormal osteoblast differentiation. The osteoblast-specific expression of the HGPS mutation increased DNA damage and affected Wnt signaling. In the teeth, irregular dentin formation, as was previously demonstrated in human progeria cases, caused severe dental abnormalities affecting the incisors. The observed phenotype also shows similarities to reported bone abnormalities in aging mice and may therefore help to uncover general principles of the aging process. PMID:22893709

  2. Expression of the Hutchinson-Gilford progeria mutation during osteoblast development results in loss of osteocytes, irregular mineralization, and poor biomechanical properties.

    Science.gov (United States)

    Schmidt, Eva; Nilsson, Ola; Koskela, Antti; Tuukkanen, Juha; Ohlsson, Claes; Rozell, Björn; Eriksson, Maria

    2012-09-28

    Hutchinson-Gilford progeria syndrome (HGPS) is a very rare genetic disorder that is characterized by multiple features of premature aging and largely affects tissues of mesenchymal origin. In this study, we describe the development of a tissue-specific mouse model that overexpresses the most common HGPS mutation (LMNA, c.1824C>T, p.G608G) in osteoblasts. Already at the age of 5 weeks, HGPS mutant mice show growth retardation, imbalanced gait and spontaneous fractures. Histopathological examination revealed an irregular bone structure, characterized by widespread loss of osteocytes, defects in mineralization, and a hypocellular red bone marrow. Computerized tomography analysis demonstrated impaired skeletal geometry and altered bone structure. The skeletal defects, which resemble the clinical features reported for bone disease in HGPS patients, was associated with an abnormal osteoblast differentiation. The osteoblast-specific expression of the HGPS mutation increased DNA damage and affected Wnt signaling. In the teeth, irregular dentin formation, as was previously demonstrated in human progeria cases, caused severe dental abnormalities affecting the incisors. The observed phenotype also shows similarities to reported bone abnormalities in aging mice and may therefore help to uncover general principles of the aging process.

  3. Transgene silencing of the Hutchinson-Gilford progeria syndrome mutation results in a reversible bone phenotype, whereas resveratrol treatment does not show overall beneficial effects.

    Science.gov (United States)

    Strandgren, Charlotte; Nasser, Hasina Abdul; McKenna, Tomás; Koskela, Antti; Tuukkanen, Juha; Ohlsson, Claes; Rozell, Björn; Eriksson, Maria

    2015-08-01

    Hutchinson-Gilford progeria syndrome (HGPS) is a rare premature aging disorder that is most commonly caused by a de novo point mutation in exon 11 of the LMNA gene, c.1824C>T, which results in an increased production of a truncated form of lamin A known as progerin. In this study, we used a mouse model to study the possibility of recovering from HGPS bone disease upon silencing of the HGPS mutation, and the potential benefits from treatment with resveratrol. We show that complete silencing of the transgenic expression of progerin normalized bone morphology and mineralization already after 7 weeks. The improvements included lower frequencies of rib fractures and callus formation, an increased number of osteocytes in remodeled bone, and normalized dentinogenesis. The beneficial effects from resveratrol treatment were less significant and to a large extent similar to mice treated with sucrose alone. However, the reversal of the dental phenotype of overgrown and laterally displaced lower incisors in HGPS mice could be attributed to resveratrol. Our results indicate that the HGPS bone defects were reversible upon suppressed transgenic expression and suggest that treatments targeting aberrant progerin splicing give hope to patients who are affected by HGPS.

  4. Blocking protein farnesylation improves nuclear shape abnormalities in keratinocytes of mice expressing the prelamin A variant in Hutchinson-Gilford progeria syndrome.

    Science.gov (United States)

    Wang, Yuexia; Ostlund, Cecilia; Worman, Howard J

    2010-01-01

    Hutchinson-Gilford progeria syndrome (HGPS) is an accelerated aging disorder caused by mutations in LMNA leading to expression of a truncated prelamin A variant termed progerin. Whereas a farnesylated polypeptide is normally removed from the carboxyl-terminus of prelamin A during endoproteolytic processing to lamin A, progerin lacks the cleavage site and remains farnesylated. Cultured cells from human subjects with HGPS and genetically modified mice expressing progerin have nuclear morphological abnormalities, which are reversed by inhibitors of protein farnesylation. In addition, treatment with protein farnesyltransferase inhibitors improves whole animal phenotypes in mouse models of HGPS. However, improvement in nuclear morphology in tissues after treatment of animals has not been demonstrated. We therefore treated transgenic mice that express progerin in epidermis with the protein farnesyltransferase inhibitor FTI-276 or a combination of pravastatin and zoledronate to determine if they reversed nuclear morphological abnormalities in tissue. Immunofluorescence microscopy and "blinded" electron microscopic analysis demonstrated that systemic administration of FTI-276 or pravastatin plus zoledronate significantly improved nuclear morphological abnormalities in keratinocytes of transgenic mice. These results show that pharmacological blockade of protein prenylation reverses nuclear morphological abnormalities that occur in HGPS in vivo. They further suggest that skin biopsy may be useful to determine if protein farnesylation inhibitors are exerting effects in subjects with HGPS in clinical trials.

  5. Correlated alterations in genome organization, histone methylation, and DNA-lamin A/C interactions in Hutchinson-Gilford progeria syndrome.

    Science.gov (United States)

    McCord, Rachel Patton; Nazario-Toole, Ashley; Zhang, Haoyue; Chines, Peter S; Zhan, Ye; Erdos, Michael R; Collins, Francis S; Dekker, Job; Cao, Kan

    2013-02-01

    Hutchinson-Gilford progeria syndrome (HGPS) is a premature aging disease that is frequently caused by a de novo point mutation at position 1824 in LMNA. This mutation activates a cryptic splice donor site in exon 11, and leads to an in-frame deletion within the prelamin A mRNA and the production of a dominant-negative lamin A protein, known as progerin. Here we show that primary HGPS skin fibroblasts experience genome-wide correlated alterations in patterns of H3K27me3 deposition, DNA-lamin A/C associations, and, at late passages, genome-wide loss of spatial compartmentalization of active and inactive chromatin domains. We further demonstrate that the H3K27me3 changes associate with gene expression alterations in HGPS cells. Our results support a model that the accumulation of progerin in the nuclear lamina leads to altered H3K27me3 marks in heterochromatin, possibly through the down-regulation of EZH2, and disrupts heterochromatin-lamina interactions. These changes may result in transcriptional misregulation and eventually trigger the global loss of spatial chromatin compartmentalization in late passage HGPS fibroblasts.

  6. Naïve adult stem cells from patients with Hutchinson-Gilford progeria syndrome express low levels of progerin in vivo

    Directory of Open Access Journals (Sweden)

    Vera Wenzel

    2012-04-01

    Hutchinson-Gilford progeria syndrome (HGPS, OMIM 176670 is a rare disorder characterized by segmental accelerated aging and early death from coronary artery disease or stroke. Nearly 90% of HGPS sufferers carry a G608G mutation within exon 11 of LMNA, producing a truncated form of prelamin A, referred to as “progerin”. Here, we report the isolation of naïve multipotent skin-derived precursor (SKP cells from dermal fibroblast cultures from HGPS donors. These cells form spheres and express the neural crest marker, nestin, in addition to the multipotent markers, OCT4, Sox2, Nanog and TG30; these cells can self-renew and differentiate into smooth muscle cells (SMCs and fibroblasts. The SMCs derived from the HGPS-SKPs accumulate nuclear progerin with increasing passages. A subset of the HGPS-naïve SKPs express progerin in vitro and in situ in HGPS skin sections. This is the first in vivo evidence that progerin is produced in adult stem cells, and implies that this protein could induce stem cells exhaustion as a mechanism contributing to aging. Our study provides a basis on which to explore therapeutic applications for HGPS stem cells and opens avenues for investigating the pathogenesis of other genetic diseases.

  7. Unique Preservation of Neural Cells in Hutchinson- Gilford Progeria Syndrome Is Due to the Expression of the Neural-Specific miR-9 MicroRNA

    Directory of Open Access Journals (Sweden)

    Xavier Nissan

    2012-07-01

    Full Text Available One puzzling observation in patients affected with Hutchinson-Gilford progeria syndrome (HGPS, who overall exhibit systemic and dramatic premature aging, is the absence of any conspicuous cognitive impairment. Recent studies based on induced pluripotent stem cells derived from HGPS patient cells have revealed a lack of expression in neural derivatives of lamin A, a major isoform of LMNA that is initially produced as a precursor called prelamin A. In HGPS, defective maturation of a mutated prelamin A induces the accumulation of toxic progerin in patient cells. Here, we show that a microRNA, miR-9, negatively controls lamin A and progerin expression in neural cells. This may bear major functional correlates, as alleviation of nuclear blebbing is observed in nonneural cells after miR-9 overexpression. Our results support the hypothesis, recently proposed from analyses in mice, that protection of neural cells from progerin accumulation in HGPS is due to the physiologically restricted expression of miR-9 to that cell lineage.

  8. The mutant form of lamin A that causes Hutchinson-Gilford progeria is a biomarker of cellular aging in human skin.

    Directory of Open Access Journals (Sweden)

    Dayle McClintock

    Full Text Available Hutchinson-Gilford progeria syndrome (HGPS, OMIM 176670 is a rare disorder characterized by accelerated aging and early death, frequently from stroke or coronary artery disease. 90% of HGPS cases carry the LMNA G608G (GGC>GGT mutation within exon 11 of LMNA, activating a splice donor site that results in production of a dominant negative form of lamin A protein, denoted progerin. Screening 150 skin biopsies from unaffected individuals (newborn to 97 years showed that a similar splicing event occurs in vivo at a low level in the skin at all ages. While progerin mRNA remains low, the protein accumulates in the skin with age in a subset of dermal fibroblasts and in a few terminally differentiated keratinocytes. Progerin-positive fibroblasts localize near the basement membrane and in the papillary dermis of young adult skin; however, their numbers increase and their distribution reaches the deep reticular dermis in elderly skin. Our findings demonstrate that progerin expression is a biomarker of normal cellular aging and may potentially be linked to terminal differentiation and senescence in elderly individuals.

  9. Unique preservation of neural cells in Hutchinson- Gilford progeria syndrome is due to the expression of the neural-specific miR-9 microRNA.

    Science.gov (United States)

    Nissan, Xavier; Blondel, Sophie; Navarro, Claire; Maury, Yves; Denis, Cécile; Girard, Mathilde; Martinat, Cécile; De Sandre-Giovannoli, Annachiara; Levy, Nicolas; Peschanski, Marc

    2012-07-26

    One puzzling observation in patients affected with Hutchinson-Gilford progeria syndrome (HGPS), who overall exhibit systemic and dramatic premature aging, is the absence of any conspicuous cognitive impairment. Recent studies based on induced pluripotent stem cells derived from HGPS patient cells have revealed a lack of expression in neural derivatives of lamin A, a major isoform of LMNA that is initially produced as a precursor called prelamin A. In HGPS, defective maturation of a mutated prelamin A induces the accumulation of toxic progerin in patient cells. Here, we show that a microRNA, miR-9, negatively controls lamin A and progerin expression in neural cells. This may bear major functional correlates, as alleviation of nuclear blebbing is observed in nonneural cells after miR-9 overexpression. Our results support the hypothesis, recently proposed from analyses in mice, that protection of neural cells from progerin accumulation in HGPS is due to the physiologically restricted expression of miR-9 to that cell lineage.

  10. Genome-scale expression profiling of Hutchinson-Gilford progeria syndrome reveals widespread transcriptional misregulation leading to mesodermal/mesenchymal defects and accelerated atherosclerosis.

    Science.gov (United States)

    Csoka, Antonei B; English, Sangeeta B; Simkevich, Carl P; Ginzinger, David G; Butte, Atul J; Schatten, Gerald P; Rothman, Frank G; Sedivy, John M

    2004-08-01

    Hutchinson-Gilford progeria syndrome (HGPS) is a rare genetic disease with widespread phenotypic features resembling premature aging. HGPS was recently shown to be caused by dominant mutations in the LMNA gene, resulting in the in-frame deletion of 50 amino acids near the carboxyl terminus of the encoded lamin A protein. Children with this disease typically succumb to myocardial infarction or stroke caused by severe atherosclerosis at an average age of 13 years. To elucidate further the molecular pathogenesis of this disease, we compared the gene expression patterns of three HGPS fibroblast cell strains heterozygous for the LMNA mutation with three normal, age-matched cell strains. We defined a set of 361 genes (1.1% of the approximately 33,000 genes analysed) that showed at least a 2-fold, statistically significant change. The most prominent categories encode transcription factors and extracellular matrix proteins, many of which are known to function in the tissues severely affected in HGPS. The most affected gene, MEOX2/GAX, is a homeobox transcription factor implicated as a negative regulator of mesodermal tissue proliferation. Thus, at the gene expression level, HGPS shows the hallmarks of a developmental disorder affecting mesodermal and mesenchymal cell lineages. The identification of a large number of genes implicated in atherosclerosis is especially valuable, because it provides clues to pathological processes that can now be investigated in HGPS patients or animal models.

  11. The mutant form of lamin A that causes Hutchinson-Gilford progeria is a biomarker of cellular aging in human skin.

    Science.gov (United States)

    McClintock, Dayle; Ratner, Desiree; Lokuge, Meepa; Owens, David M; Gordon, Leslie B; Collins, Francis S; Djabali, Karima

    2007-12-05

    Hutchinson-Gilford progeria syndrome (HGPS, OMIM 176670) is a rare disorder characterized by accelerated aging and early death, frequently from stroke or coronary artery disease. 90% of HGPS cases carry the LMNA G608G (GGC>GGT) mutation within exon 11 of LMNA, activating a splice donor site that results in production of a dominant negative form of lamin A protein, denoted progerin. Screening 150 skin biopsies from unaffected individuals (newborn to 97 years) showed that a similar splicing event occurs in vivo at a low level in the skin at all ages. While progerin mRNA remains low, the protein accumulates in the skin with age in a subset of dermal fibroblasts and in a few terminally differentiated keratinocytes. Progerin-positive fibroblasts localize near the basement membrane and in the papillary dermis of young adult skin; however, their numbers increase and their distribution reaches the deep reticular dermis in elderly skin. Our findings demonstrate that progerin expression is a biomarker of normal cellular aging and may potentially be linked to terminal differentiation and senescence in elderly individuals.

  12. Signaling pathway activation drift during aging: Hutchinson-Gilford Progeria Syndrome fibroblasts are comparable to normal middle-age and old-age cells.

    Science.gov (United States)

    Aliper, Alexander M; Csoka, Antonei Benjamin; Buzdin, Anton; Jetka, Tomasz; Roumiantsev, Sergey; Moskalev, Alexy; Zhavoronkov, Alex

    2015-01-01

    For the past several decades, research in understanding the molecular basis of human aging has progressed significantly with the analysis of premature aging syndromes. Progerin, an altered form of lamin A, has been identified as the cause of premature aging in Hutchinson-Gilford Progeria Syndrome (HGPS), and may be a contributing causative factor in normal aging. However, the question of whether HGPS actually recapitulates the normal aging process at the cellular and organismal level, or simply mimics the aging phenotype is widely debated. In the present study we analyzed publicly available microarray datasets for fibroblasts undergoing cellular aging in culture, as well as fibroblasts derived from young, middle-age, and old-age individuals, and patients with HGPS. Using GeroScope pathway analysis and drug discovery platform we analyzed the activation states of 65 major cellular signaling pathways. Our analysis reveals that signaling pathway activation states in cells derived from chronologically young patients with HGPS strongly resemble cells taken from normal middle-aged and old individuals. This clearly indicates that HGPS may truly represent accelerated aging, rather than being just a simulacrum. Our data also points to potential pathways that could be targeted to develop drugs and drug combinations for both HGPS and normal aging.

  13. Defective DSB repair correlates with abnormal nuclear morphology and is improved with FTI treatment in Hutchinson-Gilford progeria syndrome fibroblasts.

    Science.gov (United States)

    Constantinescu, Dan; Csoka, Antonei B; Navara, Christopher S; Schatten, Gerald P

    2010-10-15

    Impaired DSB repair has been implicated as a molecular mechanism contributing to the accelerating aging phenotype in Hutchinson-Gilford progeria syndrome (HGPS), but neither the extent nor the cause of the repair deficiency has been fully elucidated. Here we perform a quantitative analysis of the steady-state number of DSBs and the repair kinetics of ionizing radiation (IR)-induced DSBs in HGPS cells. We report an elevated steady-state number of DSBs and impaired repair of IR-induced DSBs, both of which correlated strongly with abnormal nuclear morphology. We recreated the HGPS cellular phenotype in human coronary artery endothelial cells for the first time by lentiviral transduction of GFP-progerin, which also resulted in impaired repair of IR-induced DSBs, and which correlated with abnormal nuclear morphology. Farnesyl transferase inhibitor (FTI) treatment improved the repair of IR-induced DSBs, but only in HGPS cells whose nuclear morphology was also normalized. Interestingly, FTI treatment did not result in a statistically significant reduction in the higher steady-state number of DSBs. We also report a delay in localization of phospho-NBS1 and MRE11, MRN complex repair factors necessary for homologous recombination (HR) repair, to DSBs in HGPS cells. Our results demonstrate a correlation between nuclear structural abnormalities and the DSB repair defect, suggesting a mechanistic link that may involve delayed repair factor localization to DNA damage. Further, our results show that similar to other HGPS phenotypes, FTI treatment has a beneficial effect on DSB repair.

  14. Wideband CMOS receivers

    CERN Document Server

    Oliveira, Luis

    2015-01-01

    This book demonstrates how to design a wideband receiver operating in current mode, in which the noise and non-linearity are reduced, implemented in a low cost single chip, using standard CMOS technology.  The authors present a solution to remove the transimpedance amplifier (TIA) block and connect directly the mixer’s output to a passive second-order continuous-time Σ∆ analog to digital converter (ADC), which operates in current-mode. These techniques enable the reduction of area, power consumption, and cost in modern CMOS receivers.

  15. Zero-power receiver

    Energy Technology Data Exchange (ETDEWEB)

    Brocato, Robert W.

    2016-10-04

    An unpowered signal receiver and a method for signal reception detects and responds to very weak signals using pyroelectric devices as impedance transformers and/or demodulators. In some embodiments, surface acoustic wave devices (SAW) are also used. Illustrative embodiments include satellite and long distance terrestrial communications applications.

  16. Sender-Receiver Games

    NARCIS (Netherlands)

    Peeters, R.J.A.P.; Potters, J.A.M.

    1999-01-01

    Standard game-theoretic solution concepts do not guarantee meaningful commu- nication in cheap-talk games. In this paper, we define a solution concept which guarantees communication for a large class of games by designing a behavior pro- tocol which the receiver uses to judge messages sent by the

  17. Discordant gene expression signatures and related phenotypic differences in lamin A- and A/C-related Hutchinson-Gilford progeria syndrome (HGPS.

    Directory of Open Access Journals (Sweden)

    Martina Plasilova

    Full Text Available Hutchinson-Gilford progeria syndrome (HGPS is a genetic disorder displaying features reminiscent of premature senescence caused by germline mutations in the LMNA gene encoding lamin A and C, essential components of the nuclear lamina. By studying a family with homozygous LMNA mutation (K542N, we showed that HGPS can also be caused by mutations affecting both isoforms, lamin A and C. Here, we aimed to elucidate the molecular mechanisms underlying the pathogenesis in both, lamin A- (sporadic and lamin A and C-related (hereditary HGPS. For this, we performed detailed molecular studies on primary fibroblasts of hetero- and homozygous LMNA K542N mutation carriers, accompanied with clinical examinations related to the molecular findings. By assessing global gene expression we found substantial overlap in altered transcription profiles (13.7%; 90/657 in sporadic and hereditary HGPS, with 83.3% (75/90 concordant and 16.7% (15/90 discordant transcriptional changes. Among the concordant ones we observed down-regulation of TWIST2, whose inactivation in mice and humans leads to loss of subcutaneous fat and dermal appendages, and loss of expression in dermal fibroblasts and periadnexial cells from a LMNA(K542N/K542N patient further confirming its pivotal role in skin development. Among the discordant transcriptional profiles we identified two key mediators of vascular calcification and bone metabolism, ENPP1 and OPG, which offer a molecular explanation for the major phenotypic differences in vascular and bone disease in sporadic and hereditary HGPS. Finally, this study correlates reduced TWIST2 and OPG expression with increased osteocalcin levels, thereby linking altered bone remodeling to energy homeostasis in hereditary HGPS.

  18. Discordant Gene Expression Signatures and Related Phenotypic Differences in Lamin A- and A/C-Related Hutchinson-Gilford Progeria Syndrome (HGPS)

    Science.gov (United States)

    Plasilova, Martina; Chattopadhyay, Chandon; Ghosh, Apurba; Wenzel, Friedel; Demougin, Philippe; Noppen, Christoph; Schaub, Nathalie; Szinnai, Gabor; Terracciano, Luigi; Heinimann, Karl

    2011-01-01

    Hutchinson-Gilford progeria syndrome (HGPS) is a genetic disorder displaying features reminiscent of premature senescence caused by germline mutations in the LMNA gene encoding lamin A and C, essential components of the nuclear lamina. By studying a family with homozygous LMNA mutation (K542N), we showed that HGPS can also be caused by mutations affecting both isoforms, lamin A and C. Here, we aimed to elucidate the molecular mechanisms underlying the pathogenesis in both, lamin A- (sporadic) and lamin A and C-related (hereditary) HGPS. For this, we performed detailed molecular studies on primary fibroblasts of hetero- and homozygous LMNA K542N mutation carriers, accompanied with clinical examinations related to the molecular findings. By assessing global gene expression we found substantial overlap in altered transcription profiles (13.7%; 90/657) in sporadic and hereditary HGPS, with 83.3% (75/90) concordant and 16.7% (15/90) discordant transcriptional changes. Among the concordant ones we observed down-regulation of TWIST2, whose inactivation in mice and humans leads to loss of subcutaneous fat and dermal appendages, and loss of expression in dermal fibroblasts and periadnexial cells from a LMNAK542N/K542N patient further confirming its pivotal role in skin development. Among the discordant transcriptional profiles we identified two key mediators of vascular calcification and bone metabolism, ENPP1 and OPG, which offer a molecular explanation for the major phenotypic differences in vascular and bone disease in sporadic and hereditary HGPS. Finally, this study correlates reduced TWIST2 and OPG expression with increased osteocalcin levels, thereby linking altered bone remodeling to energy homeostasis in hereditary HGPS. PMID:21738662

  19. Loss of H3K9me3 Correlates with ATM Activation and Histone H2AX Phosphorylation Deficiencies in Hutchinson-Gilford Progeria Syndrome

    Science.gov (United States)

    Zhang, Haoyue; Sun, Linlin; Wang, Kun; Wu, Di; Trappio, Mason; Witting, Celeste; Cao, Kan

    2016-01-01

    Compelling evidence suggests that defective DNA damage response (DDR) plays a key role in the premature aging phenotypes in Hutchinson-Gilford progeria syndrome (HGPS). Studies document widespread alterations in histone modifications in HGPS cells, especially, the global loss of histone H3 trimethylated on lysine 9 (H3K9me3). In this study, we explore the potential connection(s) between H3K9me3 loss and the impaired DDR in HGPS. When cells are exposed to a DNA-damaging agent Doxorubicin (Dox), double strand breaks (DSBs) are generated that result in the phosphorylation of histone H2A variant H2AX (gammaH2AX) within an hour. We find that the intensities of gammaH2AX foci appear significantly weaker in the G0/G1 phase HGPS cells compared to control cells. This reduction is associated with a delay in the recruitment of essential DDR factors. We further demonstrate that ataxia-telangiectasia mutated (ATM) is responsible for the amplification of gammaH2AX signals at DSBs during G0/G1 phase, and its activation is inhibited in the HGPS cells that display significant loss of H3K9me3. Moreover, methylene (MB) blue treatment, which is known to save heterochromatin loss in HGPS, restores H3K9me3, stimulates ATM activity, increases gammaH2AX signals and rescues deficient DDR. In summary, this study demonstrates an early DDR defect of attenuated gammaH2AX signals in G0/G1 phase HGPS cells and provides a plausible connection between H3K9me3 loss and DDR deficiency. PMID:27907109

  20. Dermal fibroblasts in Hutchinson-Gilford progeria syndrome with the lamin A G608G mutation have dysmorphic nuclei and are hypersensitive to heat stress

    Directory of Open Access Journals (Sweden)

    Worman Howard J

    2005-06-01

    Full Text Available Abstract Background Hutchinson-Gilford progeria syndrome (HGPS, OMIM 176670 is a rare sporadic disorder with an incidence of approximately 1 per 8 million live births. The phenotypic appearance consists of short stature, sculptured nose, alopecia, prominent scalp veins, small face, loss of subcutaneous fat, faint mid-facial cyanosis, and dystrophic nails. HGPS is caused by mutations in LMNA, the gene that encodes nuclear lamins A and C. The most common mutation in subjects with HGPS is a de novo single-base pair substitution, G608G (GGC>GGT, within exon 11 of LMNA. This creates an abnormal splice donor site, leading to expression of a truncated protein. Results We studied a new case of a 5 year-old girl with HGPS and found a heterozygous point mutation, G608G, in LMNA. Complementary DNA sequencing of RNA showed that this mutation resulted in the deletion of 50 amino acids in the carboxyl-terminal tail domain of prelamin A. We characterized a primary dermal fibroblast cell line derived from the subject's skin. These cells expressed the mutant protein and exhibited a normal growth rate at early passage in primary culture but showed alterations in nuclear morphology. Expression levels and overall distributions of nuclear lamins and emerin, an integral protein of the inner nuclear membrane, were not dramatically altered. Ultrastructural analysis of the nuclear envelope using electron microscopy showed that chromatin is in close association to the nuclear lamina, even in areas with abnormal nuclear envelope morphology. The fibroblasts were hypersensitive to heat shock, and demonstrated a delayed response to heat stress. Conclusion Dermal fibroblasts from a subject with HGPS expressing a mutant truncated lamin A have dysmorphic nuclei, hypersensitivity to heat shock, and delayed response to heat stress. This suggests that the mutant protein, even when expressed at low levels, causes defective cell stability, which may be responsible for phenotypic

  1. Digital Receiver Phase Meter

    Science.gov (United States)

    Marcin, Martin; Abramovici, Alexander

    2008-01-01

    The software of a commercially available digital radio receiver has been modified to make the receiver function as a two-channel low-noise phase meter. This phase meter is a prototype in the continuing development of a phase meter for a system in which radiofrequency (RF) signals in the two channels would be outputs of a spaceborne heterodyne laser interferometer for detecting gravitational waves. The frequencies of the signals could include a common Doppler-shift component of as much as 15 MHz. The phase meter is required to measure the relative phases of the signals in the two channels at a sampling rate of 10 Hz at a root power spectral density digital receiver. The input RF signal is first fed to the input terminal of an analog-to-digital converter (ADC). To prevent aliasing errors in the ADC, the sampling rate must be at least twice the input signal frequency. The sampling rate of the ADC is governed by a sampling clock, which also drives a digital local oscillator (DLO), which is a direct digital frequency synthesizer. The DLO produces samples of sine and cosine signals at a programmed tuning frequency. The sine and cosine samples are mixed with (that is, multiplied by) the samples from the ADC, then low-pass filtered to obtain in-phase (I) and quadrature (Q) signal components. A digital signal processor (DSP) computes the ratio between the Q and I components, computes the phase of the RF signal (relative to that of the DLO signal) as the arctangent of this ratio, and then averages successive such phase values over a time interval specified by the user.

  2. Pressure difference receiving ears

    DEFF Research Database (Denmark)

    Michelsen, Axel; Larsen, Ole Næsbye

    2007-01-01

    of such pressure difference receiving ears have been hampered by lack of suitable experimental methods. In this review, we review the methods for collecting reliable data on the binaural directional cues at the eardrums, on how the eardrum vibrations depend on the direction of sound incidence, and on how sound...... waves behave in the air spaces leading to the interior surfaces of eardrums. A linear mathematical model with well-defined inputs is used for exploring how the directionality varies with the binaural directional cues and the amplitude and phase gain of the sound pathway to the inner surface...

  3. The Pathogenic Mechanisms and Therapeutic Strategies of Hutchinson-Gilford Progeria Syndrome%早老症(HGPS)的发病机制与治疗策略

    Institute of Scientific and Technical Information of China (English)

    曾涛; 刘新光; 周中军

    2007-01-01

    早老症(Hutchinson-Gilford Progeria Syndrome,HGPS)是一种早发而严重的过早老化性疾病.它是由于编码A/C型核纤层蛋白的LMNA基因发生点突变而引起.这个突变激活了基因11号外显子上一个隐蔽的剪接位点,产生了一种被截短了50个氨基酸的A型核纤层蛋白.然而,一个广泛分布于核膜上结构蛋白的突变,如何引起HGPS患者的早老表现,目前还不太清楚.最近研究发现,HGPS患者的细胞核结构与功能发生了各种异常,主要表现在:progerin蓄积与核变形、细胞核机械性质的改变、组蛋白修饰方式与外遗传控制的改变、基因表达调控异常、p53信号传导通路激活和基因组不稳定等方面.目前存在机械应激假说和基因表达失控假说两种假说解释HGPS的发病机制.对于HGPS患者,尚无有效的临床干预措施,但有学者提出了一些治疗策略,如应用法尼基化的抑制剂、反义寡核苷酸和RNA干扰方法.HGPS被认为是研究正常衰老机制的一个模型.对HGPS深入研究将有助于阐明A型核纤层蛋白和核膜的正常生理功能,及其在生理衰老和疾病中的作用.

  4. CERN apprentice receives award

    CERN Multimedia

    2008-01-01

    Another CERN apprentice has received an award for the quality of his work. Stéphane Küng (centre), at the UIG ceremony last November, presided over by Geneva State Councillor Pierre-François Unger, Head of the Department of Economics and Health. Electronics technician Stéphane Küng was honoured in November by the Social Foundation of the Union Industrielle Genevoise (UIG) as one of Geneva’s eight best apprentices in the field of mechatronics. The 20-year-old Genevan obtained his Federal apprentice’s certificate (Certificat fédéral de capacité - CFC) in June 2007, achieving excellent marks in his written tests at the Centre d’Enseignement Professionnel Technique et Artisanal (CEPTA). Like more than 200 youngsters before him, Stéphane Küng spent part of his four-year sandwich course working at CERN, where he followed many practical training courses and gained valuable hands-on experience in various technical groups and labs. "It’ always very gr...

  5. Excel Center

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Citigroup,one of the World top 500 companies,has now settled in Excel Center,Financial Street. The opening ceremony of Excel Center and the entry ceremony of Citigroup in the center were held on March 31.Government leaders of Xicheng District,the Excel CEO and the heads of Asia-Pacific Region leaders of Citibank all participated in the ceremony.

  6. Center for Creative Studies, Detroit

    Science.gov (United States)

    AIA Journal, 1976

    1976-01-01

    One of the ten buildings chosen to receive 1976 AIA honor awards, the arts center houses the departments of sculpture, painting, graphics, advertising art, photography, and industrial design. (Author/MLF)

  7. Center for Creative Studies, Detroit

    Science.gov (United States)

    AIA Journal, 1976

    1976-01-01

    One of the ten buildings chosen to receive 1976 AIA honor awards, the arts center houses the departments of sculpture, painting, graphics, advertising art, photography, and industrial design. (Author/MLF)

  8. GNSS Software Receiver for UAVs

    DEFF Research Database (Denmark)

    Olesen, Daniel Madelung; Jakobsen, Jakob; von Benzon, Hans-Henrik

    2016-01-01

    This paper describes the current activities of GPS/GNSS Software receiver development at DTU Space. GNSS Software receivers have received a great deal of attention in the last two decades and numerous implementations have already been presented. DTU Space has just recently started development of ...... of our own GNSS software-receiver targeted for mini UAV applications, and we will in in this paper present our current progress and briefly discuss the benefits of Software Receivers in relation to our research interests....

  9. Hutchinson-Gilford progeria syndrome

    OpenAIRE

    Agarwal Uma; Sitaraman S; Mehta Sharad; Panse Gauri

    2010-01-01

    Progeria is a rare genetic disorder characterized by premature aging, involving the skin, bones, heart, and blood vessels. We report a 4-year-old boy who presented with clinical manifestations of progeria. He had characteristic facies, prominent eyes, scalp and leg veins, senile look, loss of scalp hair, eyebrows and eyelashes, stunted growth, and sclerodermatous changes. The present case is reported due to its rarity.

  10. Hutchinson-Gilford progeria syndrome

    Directory of Open Access Journals (Sweden)

    Agarwal Uma

    2010-01-01

    Full Text Available Progeria is a rare genetic disorder characterized by premature aging, involving the skin, bones, heart, and blood vessels. We report a 4-year-old boy who presented with clinical manifestations of progeria. He had characteristic facies, prominent eyes, scalp and leg veins, senile look, loss of scalp hair, eyebrows and eyelashes, stunted growth, and sclerodermatous changes. The present case is reported due to its rarity.

  11. Application effect of active and effective care in center venous catheter in patients receiving hemodialysis%积极有效护理在血液透析患者中心静脉置管中的应用效果

    Institute of Scientific and Technical Information of China (English)

    潘光易

    2015-01-01

    Objective To explore application effect of active and effective care in center venous catheter in patients re-ceiving hemodialysis. Methods 60 patients received hemodialysis with central venous catheter from January 2011 to January 2013 in our hospital were randomly selected as the experimental group,and were given the central venous catheter care,effective care after treatment.While,60 patients underwent hemodialasis with central venous catheter from January 2008 to December 2009 in our hospital were randomly selected as the control group,and were given routine nursing care.The incidence rate of infection in two group was compared. Results The incidence rate of infection in the experimental group was 5.0%,which was significantly lower than 26.7% in the control group,with significant difference (P<0.05). Conclusion Effective nursing measures can reduce the incidence of hemodialysis patients with central venous catheter infection.%目的:探讨积极有效护理在血液透析患者中心静脉置管中的应用效果。方法随机选取2011年1月~2013年1月在本院接受血液透析中心静脉置管的60例患者作为实验组,给予中心静脉置管护理、置管后处理等有效护理,同时随机选取2008年1月~2009年12月在本院行血液透析中心静脉置管的60例患者作为对照组,给予常规护理措施。比较两组的感染发生率。结果实验组的感染发生率为5.0%,显著低于对照组的26.7%,差异有统计学意义(P<0.05)。结论采取有效的护理措施能够控制血液透析患者中心静脉导管感染发生率。

  12. Communications receivers principles and design

    CERN Document Server

    Rohde, Ulrich L; Zahnd, Hans

    2017-01-01

    This thoroughly updated guide offers comprehensive explanations of the science behind today’s radio receivers along with practical guidance on designing, constructing, and maintaining real-world communications systems. You will explore system planning, antennas and antenna coupling, amplifiers and gain control, filters, mixers, demodulation, digital communication, and the latest software defined radio (SDR) technology. Written by a team of telecommunication experts, Communications Receivers: Principles and Design, Fourth Edition, features technical illustrations, schematic diagrams, and detailed examples. Coverage includes: • Basic radio considerations • Radio receiver characteristics • Receiver system planning • Receiver implementation considerations • RF and baseband techniques for Software-Defined Radios • Transceiver SDR considerations • Antennas and antenna coupling • Mixers • Frequency sources and control • Ancillary receiver circuits • Performance measurement

  13. Analysis of a case with typical Hutchinson-Gilford progeria syndrome with scleroderma-like skin changes and review of literature%伴硬皮病样改变的典型Hutchinson-Gilford早老综合征一例并文献复习

    Institute of Scientific and Technical Information of China (English)

    黄姗; 梁雁; 吴薇; 付溪; 廖立红; 罗小平

    2014-01-01

    目的 探讨典型Hutchinson-Gilford早老综合征(HGPS)的临床特点及诊断.方法 回顾性分析华中科技大学同济医学院附属同济医院儿科诊断的1例典型HGPS患儿,并复习相关文献,分析本病的临床表现、影像学特点、基因突变特点及诊疗方法.结果 患儿男,8月龄,身高65.6 cm,体重6.2 kg,前额突出,枕部秃发,头皮静脉显露,小颌畸形伴下颌纵向沟,胸部以下皮肤呈硬皮病样改变,双膝关节挛缩呈“骑马样站姿”,踝关节活动亦受限.血常规示血小板(416~490)×109/L;双下肢MRI发现皮下脂肪组织减少.家系外周血LMNA基因分析示患儿携带经典杂合突变:c.1824C>T,(p.G608G),其父母均正常.13月龄随访时X线检查示双手指骨及锁骨远端有骨质溶解改变.随访15个月后,患儿早老样外貌更明显.总结相关文献发现国内结合临床特征和基因分析明确诊断的典型HGPS有2例,其中1例有硬皮病样皮肤改变.结论 患儿呈典型HGPS表型;婴儿期皮肤出现硬皮病样改变,应考虑典型HGPS的可能,且LMNA基因分析有助于典型HGPS的早期确诊,避免其他不必要的检查.应对患儿长期进行随访,观察病情持续进展.%Objective To explore clinical,radiographical and genetic characteristics of classical Hutchinson-Gilford progeria syndrome (HGPS).Method Data of a case of HGPS diagnosed at Tongji Hospital Affiliated to Tongji Medical College of Huazhong University of Science and Technology was analyzed and related literature was reviewed.Result At the age of 8 months,the affected-infant presented with characteristic manifestation such as short stature,low weight,frontal bossing,alopecia,prominent scalp veins,micrognathia with a vertical midline groove in the chin,sclerodermatous skin,knee joints contracture with a horse-riding stance,and limited range of movement of ankle joints.Blood test showed blood platelet count (416-490) × 109/L.Lower extremities MRI showed reduced

  14. The Hospital-Based Drug Information Center.

    Science.gov (United States)

    Hopkins, Leigh

    1982-01-01

    Discusses the rise of drug information centers in hospitals and medical centers, highlighting staffing, functions, typical categories of questions received by centers, and sources used. An appendix of drug information sources included in texts, updated services, journals, and computer databases is provided. Thirteen references are listed. (EJS)

  15. A GPS Receiver for Lunar Missions

    Science.gov (United States)

    Bamford, William A.; Heckler, Gregory W.; Holt, Greg N.; Moreau, Michael C.

    2008-01-01

    Beginning with the launch of the Lunar Reconnaissance Orbiter (LRO) in October of 2008, NASA will once again begin its quest to land humans on the Moon. This effort will require the development of new spacecraft which will safely transport people from the Earth to the Moon and back again, as well as robotic probes tagged with science, re-supply, and communication duties. In addition to the next-generation spacecraft currently under construction, including the Orion capsule, NASA is also investigating and developing cutting edge navigation sensors which will allow for autonomous state estimation in low Earth orbit (LEO) and cislunar space. Such instruments could provide an extra layer of redundancy in avionics systems and reduce the reliance on support and on the Deep Space Network (DSN). One such sensor is the weak-signal Global Positioning System (GPS) receiver "Navigator" being developed at NASA's Goddard Space Flight Center (GSFC). At the heart of the Navigator is a Field Programmable Gate Array (FPGA) based acquisition engine. This engine allows for the rapid acquisition/reacquisition of strong GPS signals, enabling the receiver to quickly recover from outages due to blocked satellites or atmospheric entry. Additionally, the acquisition algorithm provides significantly lower sensitivities than a conventional space-based GPS receiver, permitting it to acquire satellites well above the GPS constellation. This paper assesses the performance of the Navigator receiver based upon three of the major flight regimes of a manned lunar mission: Earth ascent, cislunar navigation, and entry. Representative trajectories for each of these segments were provided by NASA. The Navigator receiver was connected to a Spirent GPS signal generator, to allow for the collection of real-time, hardware-in-the-loop results for each phase of the flight. For each of the flight segments, the Navigator was tested on its ability to acquire and track GPS satellites under the dynamical

  16. HIGH-EFFICIENCY INFRARED RECEIVER

    Directory of Open Access Journals (Sweden)

    A. K. Esman

    2016-01-01

    Full Text Available Recent research and development show promising use of high-performance solid-state receivers of the electromagnetic radiation. These receivers are based on the low-barrier Schottky diodes. The approach to the design of the receivers on the basis of delta-doped low-barrier Schottky diodes with beam leads without bias is especially actively developing because for uncooled receivers of the microwave radiation these diodes have virtually no competition. The purpose of this work is to improve the main parameters and characteristics that determine the practical relevance of the receivers of mid-infrared electromagnetic radiation at the operating room temperature by modifying the electrodes configuration of the diode and optimizing the distance between them. Proposed original design solution of the integrated receiver of mid-infrared radiation on the basis of the low-barrier Schottky diodes with beam leads allows to effectively adjust its main parameters and characteristics. Simulation of the electromagnetic characteristics of the proposed receiver by using the software package HFSS with the basic algorithm of a finite element method which implemented to calculate the behavior of electromagnetic fields on an arbitrary geometry with a predetermined material properties have shown that when the inner parts of the electrodes of the low-barrier Schottky diode is performed in the concentric elliptical convex-concave shape, it can be reduce the reflection losses to -57.75 dB and the standing wave ratio to 1.003 while increasing the directivity up to 23 at a wavelength of 6.09 μm. At this time, the rounded radii of the inner parts of the anode and cathode electrodes are equal 212 nm and 318 nm respectively and the gap setting between them is 106 nm. These parameters will improve the efficiency of the developed infrared optical-promising and electronic equipment for various purposes intended for work in the mid-infrared wavelength range. 

  17. UWB communication receiver feedback loop

    Science.gov (United States)

    Spiridon, Alex; Benzel, Dave; Dowla, Farid U.; Nekoogar, Faranak; Rosenbury, Erwin T.

    2007-12-04

    A novel technique and structure that maximizes the extraction of information from reference pulses for UWB-TR receivers is introduced. The scheme efficiently processes an incoming signal to suppress different types of UWB as well as non-UWB interference prior to signal detection. Such a method and system adds a feedback loop mechanism to enhance the signal-to-noise ratio of reference pulses in a conventional TR receiver. Moreover, sampling the second order statistical function such as, for example, the autocorrelation function (ACF) of the received signal and matching it to the ACF samples of the original pulses for each transmitted bit provides a more robust UWB communications method and system in the presence of channel distortions.

  18. Receiver-exciter controller design

    Science.gov (United States)

    Jansma, P. A.

    1982-01-01

    A description of the general design of both the block 3 and block 4 receiver-exciter controllers for the Deep Space Network (DSN) Mark IV-A System is presented along with the design approach. The controllers are designed to enable the receiver-exciter subsystem (RCV) to be configured, calibrated, initialized and operated from a central location via high level instructions. The RECs are designed to be operated under the control of the DMC subsystem. The instructions are in the form of standard subsystem blocks (SSBs) received via the local area network (LAN). The centralized control provided by RECs and other DSCC controllers in Mark IV-A is intended to reduce DSN operations costs from the Mark III era.

  19. RFID receiver apparatus and method

    Science.gov (United States)

    Scott, Jeffrey Wayne

    2006-12-26

    An RFID backscatter interrogator for transmitting data to an RFID tag, generating a carrier for the tag, and receiving data from the tag modulated onto the carrier, the interrogator including a single grounded-coplanar wave-guide circuit board and at least one surface mount integrated circuit supported by the circuit board.

  20. LU Peizhang receives Golay Award

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ Prof. LU Peizhang, an analytical chemist with the CAS Dalian Institute of Chemical Physics, received the prestigious Golay Award at the 30th International Symposium on Capillary Chromatography opened on 5 June in Dalian, a port city in northeast China's Liaoning Province.

  1. Absorption Efficiency of Receiving Antennas

    DEFF Research Database (Denmark)

    Andersen, Jørgen Bach; Frandsen, Aksel

    2005-01-01

    A receiving antenna with a matched load will always scatter some power. This paper sets an upper and a lower bound on the absorption efficiency (absorbed power over sum of absorbed and scattered powers), which lies between 0 and 100% depending on the directivities of the antenna and scatter...

  2. Centering research

    DEFF Research Database (Denmark)

    Katan, Lina Hauge; Baarts, Charlotte

    and collected 24 portfolios in which students reflect auto-ethnographically on their educational practices. Analyzing this qualitative material, we explore how researchers and students respectively read and write to develop and advance their thinking in those learning processes that the two groups fundamentally...... share as the common aim of both research and education. Despite some similarities, we find that how the two groups engage in and benefit from reading and writing diverges significantly. Thus we have even more reason to believe that centering practice-based teaching on these aspects of research is a good...

  3. Scintillation-Hardened GPS Receiver

    Science.gov (United States)

    Stephens, Donald R.

    2015-01-01

    CommLargo, Inc., has developed a scintillation-hardened Global Positioning System (GPS) receiver that improves reliability for low-orbit missions and complies with NASA's Space Telecommunications Radio System (STRS) architecture standards. A software-defined radio (SDR) implementation allows a single hardware element to function as either a conventional radio or as a GPS receiver, providing backup and redundancy for platforms such as the International Space Station (ISS) and high-value remote sensing platforms. The innovation's flexible SDR implementation reduces cost, weight, and power requirements. Scintillation hardening improves mission reliability and variability. In Phase I, CommLargo refactored an open-source GPS software package with Kalman filter-based tracking loops to improve performance during scintillation and also demonstrated improved navigation during a geomagnetic storm. In Phase II, the company generated a new field-programmable gate array (FPGA)-based GPS waveform to demonstrate on NASA's Space Communication and Navigation (SCaN) test bed.

  4. Japanese Oceanographic Data Center Japan Land Gravity

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The gravity station data (4,381 records) were compiled by the Japanese Oceanographic Data Center. This data base was received in July 1988. The data are in the...

  5. Managing Medicare receivables after PIP.

    Science.gov (United States)

    Loria, L S

    1987-04-01

    The luxury of PIP is gone and managing cash flow will become more important than ever before. The hospital industry has come a long way in the development of automated billing systems and related recordkeeping since PIP was first introduced. The performance of an operations review of the accounts receivable management system should improve the effectiveness and efficiency of operations and significantly improve cash flow.

  6. Diversity of MMSE MIMO Receivers

    CERN Document Server

    Mehana, Ahmed Hesham

    2011-01-01

    In most MIMO systems, the family of waterfall error curves, calculated at different spectral efficiencies, are asymptotically parallel at high SNR. In other words, most MIMO systems exhibit a single diversity value for all {\\em fixed} rates. The MIMO MMSE receiver does not follow this pattern and exhibits a varying diversity in its family of error curves. This effect cannot be captured by DMT analysis, due to the fact that all fixed rates correspond to the same multiplexing gain, thus they cannot be differentiated within DMT analysis. This work analyzes this interesting behavior of the MMSE MIMO receiver and produces the MMSE MIMO diversity at each rate. The diversity of the quasi-static flat-fading MIMO channel consisting of any arbitrary number of transmit and receive antennas is fully characterized, showing that full spatial diversity is possible for all antenna configurations if and only if the rate is within a certain bound which is a function of the number of antennas. For other rate brackets, the avail...

  7. A multi-center study on the long-term mortality and related risk factors in patients with chronic heart failure receiving resynchronization therapy%心力衰竭双心室再同步化治疗的长期死亡率及特点的多中心研究

    Institute of Scientific and Technical Information of China (English)

    齐书英; 王冬梅; 于海波; 丁超; 田福利; 汝磊生; 李洁; 张宾; 韩雅玲

    2016-01-01

    Objective To analyze long-term mortality and patients characteristics of cardiac resynchronization therapy (CRT) for patients with chronic heart failure.Methods In-patients with chronic heart failure who received CRT in the three medical centers (Bethune International Peace Hospital,General Hospital of Shenyang Military Command of Chinese People's Liberation Army,and 251 Hospital of People's Liberation Army)from March 2001 to June 2013 were included.Mortality and related causes,echocardiographic parameters were analyzed.Results A total of 200 patients were treated with CRT therapy (154 males,mean age (60.57 ± 11.75) years),59 cases suffered from ischemic cardiomyopathy (ICM),patients were followed up from 0.5 to 12 years.The all-cause mortality rate was 25.50% (51/200),20 out of 59 (33.90%) ICM patients died,as compared with 31 deaths out of 141 (21.98%) in non-ischemic cardiomyopath (NICM) patients.Thirty-six patients died due to cardiac death (70.59%),in which sudden death occurred in 21 patients (41.18%).Non-cardiac death occurred in 13 patients (25.49%),two patients died due to unknown reasons (3.92%).Incidence of cardiac death was significantly higher than non-cardiac death (P <0.01).The main cause for cardiac death was NICM (28/36,77.78%),while the main cause of non-cardiac death was ICM (11/13,84.62%,P <0.01).Patients died due to cardiac death were younger (P < 0.01) and had larger left atrial end-diastolic diameter (LAEDD) and left ventricular end-diastolic diameter (LVEDD) (P < 0.01),lower left ventricular ejection fraction (LVEF) (P < 0.05),higher pulmonary artery pressure (P < 0.05) compared to patients with non-cardiac death.One hundred and fifty-two cases received CRT-P and 48 cases received CRT-D,there were no significant differences in gender,the course of heart failure,serum creatinine levels,pre-operative and post-operative QRS duration and so on between the CRT-P and CRT-D groups (all P > 0.05).Eleven out of the 48

  8. Chip Advancer For GPS Receiver

    Science.gov (United States)

    Meehan, Thomas K.; Srinivasan, Jeffrey M.; Thomas, J. Brooks

    1989-01-01

    Instrument errors made negligible. For each integration interval, both delay and rate of change of delay initialized to small fraction of chip - for example, to order of 10 to the negative 7th power - thereby making feedback control and extraction of delay highly accurate and flexible. With appropriate selection of sampling rate relative to chip rate, commensurability errors reduced to extremely small levels. In Global Positioning System (GPS) receiver, pseudorandom code sequence generated by simple digital logic incorporating effects of time, delay, and rate of change of delay. Flexibility in starting time and sum interval very useful in aligning correlation interval with beginnings and endings of data bits.

  9. Broadband direct RF digitization receivers

    CERN Document Server

    Jamin, Olivier

    2014-01-01

    This book discusses the trade-offs involved in designing direct RF digitization receivers for the radio frequency and digital signal processing domains.  A system-level framework is developed, quantifying the relevant impairments of the signal processing chain, through a comprehensive system-level analysis.  Special focus is given to noise analysis (thermal noise, quantization noise, saturation noise, signal-dependent noise), broadband non-linear distortion analysis, including the impact of the sampling strategy (low-pass, band-pass), analysis of time-interleaved ADC channel mismatches, sampling clock purity and digital channel selection. The system-level framework described is applied to the design of a cable multi-channel RF direct digitization receiver. An optimum RF signal conditioning, and some algorithms (automatic gain control loop, RF front-end amplitude equalization control loop) are used to relax the requirements of a 2.7GHz 11-bit ADC. A two-chip implementation is presented, using BiCMOS and 65nm...

  10. 一个儿童早老症家系临床特征分析和致病基因研究%Analysis of clinical characteristics and causative genes of Hutchinson-Gilford progeria syndrome in a family

    Institute of Scientific and Technical Information of China (English)

    覃霞; 罗彦彦; 袁广之; 畅荣妮; 赖青鸟; 杨益金; 华荣; 李福记; 方玲

    2015-01-01

    Objective To assess clinicopathological features of and genetic factors in Hutchinson-Gilford progeria syndrome (HGPS) in a family.Methods General information was collected from 3 patients with HutchinsonGilford progeria syndrome in a family,which included 5 members over 2 generations with all the 3 children affected by HGPS.All the 3 patients underwent clinical investigation,image analysis of hands,lungs and mandibles,as well as karyotype analysis of chromosomes.LMNA gene mutations were analyzed in these family members.Results All the 3 patients developed skin sclerosis with severe growth retardation and appearance of extreme aging at about 6 months of age.Image analysis showed osteoporosis and mandibular hypoplasia in the elder patient.Karyotype analysis showed no abnormality in the patients or their parents.Mutation analysis revealed a homozygous mutation 1579 C > T (R527C) in exon 9 of the LMNA gene in all the patients,but a heterozygous mutation R527C in the LMNA gene in their parents.Conclusions The patients in this family present characteristic manifestations of HGPS,which may be caused by the homozygous LMNA mutation R527C.%目的 通过对一个罕见早老症家系的分析,探讨早老症患者的临床病理学特征和遗传学因素.方法 收集1个早老症家系(2代共5名家庭成员,子女3人均为患者)3例患者的基本资料,对其进行临床检查,并对患者手部、肺脏和下颌骨进行影像学分析;同时对3例患者进行染色体核型分析,对该家系进行LMNA基因突变分析.结果 家系中的3例患者半岁左右即可见皮肤硬化症,并表现出生长严重迟缓,极度衰老面容.年长患者影像学检查显示骨质疏松,下颌骨发育不全.染色体核型分析显示,3例患者及其父母核型正常.基因突变分析显示,3例患者均为LMNA基因第9号外显子的纯合突变1579C>T(R527C),父母均为LMNAR527C杂合突变.结论 该早老症家系患者符合儿童

  11. A cryogenic receiver for EPR.

    Science.gov (United States)

    Narkowicz, R; Ogata, H; Reijerse, E; Suter, D

    2013-12-01

    Cryogenic probes have significantly increased the sensitivity of NMR. Here, we present a compact EPR receiver design capable of cryogenic operation. Compared to room temperature operation, it reduces the noise by a factor of ≈2.5. We discuss in detail the design and analyze the resulting noise performance. At low microwave power, the input noise density closely follows the emission of a cooled 50Ω resistor over the whole measurement range from 20K up to room temperature. To minimize the influence of the microwave source noise, we use high microwave efficiency (≈1.1-1.7mTW(-1/2)) planar microresonators. Their efficient conversion of microwave power to magnetic field permits EPR measurements with very low power levels, typically ranging from a few μW down to fractions of nW. Copyright © 2013 Elsevier Inc. All rights reserved.

  12. CERN physicist receives Einstein Medal

    CERN Multimedia

    2006-01-01

    On 29 June the CERN theorist Gabriele Veneziano was awarded the prestigious Albert Einstein Medal for significant contributions to the understanding of string theory. This award is given by the Albert Einstein Society in Bern to individuals whose scientific contributions relate to the work of Einstein. Former recipients include exceptional physicists such as Murray Gell-Mann last year, but also Stephen Hawking and Victor Weisskopf. Gabriele Veneziano, a member of the integrated CERN Theory Team since 1977, led the Theory Division from 1994 to 1997 and has already received many prestigious prizes for his outstanding work, including the Enrico Fermi Prize (see CERN Courier, November 2005), the Dannie Heineman Prize for mathematical physics of the American Physical Society in 2004 (see Bulletin No. 47/2003), and the I. Ya. Pomeranchuk Prize of the Institute of Theoretical and Experimental Physics (Moscow) in 1999.

  13. Mississippi Technology Transfer Center

    Science.gov (United States)

    1987-01-01

    The Mississippi Technology Transfer Center at the John C. Stennis Space Center in Hancock County, Miss., was officially dedicated in 1987. The center is home to several state agencies as well as the Center For Higher Learning.

  14. Vertebrate pressure-gradient receivers.

    Science.gov (United States)

    Christensen-Dalsgaard, Jakob

    2011-03-01

    The eardrums of all terrestrial vertebrates (tetrapods) are connected through Eustachian tubes or interaural canals. In some of the animals, these connections create pressure-gradient directionality, an enhanced directionality by interaction of sound arriving at both sides of the eardrum and strongly dependent on interaural transmission attenuation. Even though the tympanic middle ear has originated independently in the major tetrapod groups, in each group the ancestral condition probably was that the two middle ears were exposed in the mouth cavity with relatively high interaural transmission. Recent vertebrates form a continuum from perfect interaural transmission (0 dB in a certain frequency band) and pronounced eardrum directionality (30-40 dB) in the lizards, over somewhat attenuated transmission and limited directionality in birds and frogs, to the strongly attenuated interaural transmission and functionally isolated pressure receiver ears in the mammals. Since some of the binaural interaction already takes place at the eardrum in animals with strongly coupled ears, producing enhanced interaural time and level differences, the subsequent neural processing may be simpler. In robotic simulations of lizards, simple binaural subtraction (EI cells, found in brainstem nuclei of both frogs and lizards) produces strongly lateralized responses that are sufficient for steering the animal robustly to sound sources.

  15. Recent developments in superconducting receivers

    Science.gov (United States)

    Richards, Paul L.

    1990-09-01

    A description is given of recent work at Berkeley on superconducting mixers and detectors for infrared and millimeter wavelengths. The first report is a review article which summarizes the status of development of superconducting components for infrared and millimeter wave receivers. The next report describes accurate measurements and also theoretical modeling of an SIS quasiparticle waveguide mixer for W-band which uses very high quality Ta junctions. The best mixer noise is only 1.3 times the quantum limit. Both the mixer gain and the noise are in quantitative agreement with the quantum theory. Next, a report is given on measurements and theoretical modeling of the absorptivity (surface resistance) of high quality epitaxial films of the high Tc superconductor YBCO from 750 GHz to 21 THz. Finally, there are reports on the design and experimental performance of two different types of high Tc bolometric detectors. One is a conventional bolometer with a gold-black absorber. The other is an antenna coupled microbolometer.

  16. The Mechanism of Company Accounts Receivable Management

    Directory of Open Access Journals (Sweden)

    Halyna Yamnenko

    2017-02-01

    Full Text Available The relevance of the accounts receivable management is caused by its ability to influence on the filling of the company working capital. Therefore it is necessary to create a specific mechanism for management of accounts receivable in the company. The article analyses the components of the mechanism and the influence of factors that significantly affect the operation. The result of the functioning of the accounts receivable management is to receive funds and to minimize accounts receivable.

  17. Comparing electronic news media reports of potential bioterrorism-related incidents involving unknown white powder to reports received by the United States Centers for Disease Control and Prevention and the Federal Bureau of Investigation: U.S.A., 2009-2011.

    Science.gov (United States)

    Fajardo, Geroncio C; Posid, Joseph; Papagiotas, Stephen; Lowe, Luis

    2015-01-01

    There have been periodic electronic news media reports of potential bioterrorism-related incidents involving unknown substances (often referred to as "white powder") since the 2001 intentional dissemination of Bacillus anthracis through the U.S. Postal System. This study reviewed the number of unknown "white powder" incidents reported online by the electronic news media and compared them with unknown "white powder" incidents reported to the U.S. Centers for Disease Control and Prevention (CDC) and the U.S. Federal Bureau of Investigation (FBI) during a 2-year period from June 1, 2009 and May 31, 2011. Results identified 297 electronic news media reports, 538 CDC reports, and 384 FBI reports of unknown "white powder." This study showed different unknown "white powder" incidents captured by each of the three sources. However, the authors could not determine the public health implications of this discordance.

  18. 50th Anniversary of the World's First Extraterrestrial Sample Receiving Laboratory: The Apollo Program's Lunar Receiving Laboratory

    Science.gov (United States)

    Calaway, M. J.; Allton, J. H.; Zeigler, R. A.; McCubbin, F. M.

    2017-01-01

    The Apollo program's Lunar Receiving Laboratory (LRL), building 37 at NASA's Manned Spaceflight Center (MSC), now Johnson Space Center (JSC), in Houston, TX, was the world's first astronaut and extraterrestrial sample quarantine facility (Fig. 1). It was constructed by Warrior Construction Co. and Warrior-Natkin-National at a cost of $8.1M be-tween August 10, 1966 and June 26, 1967. In 1969, the LRL received and curated the first collection of extra-terrestrial samples returned to Earth; the rock and soil samples of the Apollo 11 mission. This year, the JSC Astromaterials Acquisition and Curation Office (here-after JSC curation) celebrates 50 years since the opening of the LRL and its legacy of laying the foundation for modern curation of extraterrestrial samples.

  19. Thermal resistance model for CSP central receivers

    Science.gov (United States)

    de Meyer, O. A. J.; Dinter, F.; Govender, S.

    2016-05-01

    The receiver design and heliostat field aiming strategy play a vital role in the heat transfer efficiency of the receiver. In molten salt external receivers, the common operating temperature of the heat transfer fluid or molten salt ranges between 285°C to 565°C. The optimum output temperature of 565°C is achieved by adjusting the mass flow rate of the molten salt through the receiver. The reflected solar radiation onto the receiver contributes to the temperature rise in the molten salt by means of heat transfer. By investigating published work on molten salt external receiver operating temperatures, corresponding receiver tube surface temperatures and heat losses, a model has been developed to obtain a detailed thermographic representation of the receiver. The steady state model uses a receiver flux map as input to determine: i) heat transfer fluid mass flow rate through the receiver to obtain the desired molten salt output temperature of 565°C, ii) receiver surface temperatures iii) receiver tube temperatures iv) receiver efficiency v) pressure drop across the receiver and vi) corresponding tube strain per panel.

  20. Microwave receivers with electronic warfare applications

    CERN Document Server

    Tsui, James

    2005-01-01

    This book by the author of Digital Techniques for Wideband Receivers willbe like no other one on your book shelf as the definitive word on electronicwarfare (EW) receiver design and performance. Whether you are an EWscientist involved in the test and evaluation of EW receivers or a designerof RWR's and other EW-related receivers, Microwave Receivers withElectronic Warfare Applications is a handy reference through which you canperfect your technical art. Lucidly written, this book is a treatise on EWreceivers that is relevant to you if you are just looking for a top-levelinsight into EW receive

  1. An Upregulation in the Expression of Vanilloid Transient Potential Channels 2 Enhances Hypotonicity-Induced Cytosolic Ca2+ Rise in Human Induced Pluripotent Stem Cell Model of Hutchinson Gillford Progeria

    Science.gov (United States)

    Ho, Jenny Chung-Yee; Siu, Chung-Wah; Cheung, Sin-Ying; Tang, Nelson L.; Yu, Shan; Tse, Hung-Fat; Yao, Xiaoqiang

    2014-01-01

    Hutchinson-Gillford Progeria Syndrome (HGPS) is a fatal genetic disorder characterized by premature aging in multiple organs including the skin, musculoskeletal and cardiovascular systems. It is believed that an increased mechanosensitivity of HGPS cells is a causative factor for vascular cell death and vascular diseases in HGPS patients. However, the exact mechanism is unknown. Transient receptor potential (TRP) channels are cationic channels that can act as cellular sensors for mechanical stimuli. The aim of this present study was to examine the expression and functional role of TRP channels in human induced pluripotent stem cell-derived endothelial cells (iPSC-ECs) from the patients with HGPS. The mRNA and protein expression of TRP channels in HGPS and control (IMR90) iPSC-ECs were examined by semi-quantitative RT-PCRs and immunoblots, respectively. Hypotonicity-induced cytosolic Ca2+ ([Ca2+]i) rise in iPSC-ECs was measured by confocal microscopy. RT-PCRs and immunoblots showed higher expressional levels of TRPV2 in iPSC-ECs from HGPS patients than those from normal individuals. In functional studies, hypotonicity induced a transient [Ca2+]i rise in iPSC-ECs from normal individuals but a sustained [Ca2+]i elevation in iPSC-ECs from HGPS patients. A nonselective TRPV inhibitor, ruthenium red (RuR, 20 µM), and a specific TRPV2 channel inhibitor, tranilast (100 µM), abolished the sustained phase of hypotonicity-induced [Ca2+]i rise in iPSC-ECs from HGPS patients, and also markedly attenuated the transient phase of the [Ca2+]i rise in these cells. Importantly, a short 10 min hypotonicity treatment caused a substantial increase in caspase 8 activity in iPSC-ECs from HGPS patients but not in cells from normal individuals. Tranilast could also inhibit the hypotonicity-induced increase in caspase 8 activity. Taken together, our data suggest that an up-regulation in TRPV2 expression causes a sustained [Ca2+]i elevation in HGPS-iPSC-ECs under hypotonicity, consequently

  2. An upregulation in the expression of vanilloid transient potential channels 2 enhances hypotonicity-induced cytosolic Ca²⁺ rise in human induced pluripotent stem cell model of Hutchinson-Gillford Progeria.

    Directory of Open Access Journals (Sweden)

    Chun-Yin Lo

    Full Text Available Hutchinson-Gillford Progeria Syndrome (HGPS is a fatal genetic disorder characterized by premature aging in multiple organs including the skin, musculoskeletal and cardiovascular systems. It is believed that an increased mechanosensitivity of HGPS cells is a causative factor for vascular cell death and vascular diseases in HGPS patients. However, the exact mechanism is unknown. Transient receptor potential (TRP channels are cationic channels that can act as cellular sensors for mechanical stimuli. The aim of this present study was to examine the expression and functional role of TRP channels in human induced pluripotent stem cell-derived endothelial cells (iPSC-ECs from the patients with HGPS. The mRNA and protein expression of TRP channels in HGPS and control (IMR90 iPSC-ECs were examined by semi-quantitative RT-PCRs and immunoblots, respectively. Hypotonicity-induced cytosolic Ca²⁺ ([Ca²⁺](i rise in iPSC-ECs was measured by confocal microscopy. RT-PCRs and immunoblots showed higher expressional levels of TRPV2 in iPSC-ECs from HGPS patients than those from normal individuals. In functional studies, hypotonicity induced a transient [Ca²⁺](i rise in iPSC-ECs from normal individuals but a sustained [Ca²⁺](i elevation in iPSC-ECs from HGPS patients. A nonselective TRPV inhibitor, ruthenium red (RuR, 20 µM, and a specific TRPV2 channel inhibitor, tranilast (100 µM, abolished the sustained phase of hypotonicity-induced [Ca²⁺](i rise in iPSC-ECs from HGPS patients, and also markedly attenuated the transient phase of the [Ca²⁺](i rise in these cells. Importantly, a short 10 min hypotonicity treatment caused a substantial increase in caspase 8 activity in iPSC-ECs from HGPS patients but not in cells from normal individuals. Tranilast could also inhibit the hypotonicity-induced increase in caspase 8 activity. Taken together, our data suggest that an up-regulation in TRPV2 expression causes a sustained [Ca²⁺](i elevation in HGPS

  3. An upregulation in the expression of vanilloid transient potential channels 2 enhances hypotonicity-induced cytosolic Ca²⁺ rise in human induced pluripotent stem cell model of Hutchinson-Gillford Progeria.

    Science.gov (United States)

    Lo, Chun-Yin; Tjong, Yung-Wui; Ho, Jenny Chung-Yee; Siu, Chung-Wah; Cheung, Sin-Ying; Tang, Nelson L; Yu, Shan; Tse, Hung-Fat; Yao, Xiaoqiang

    2014-01-01

    Hutchinson-Gillford Progeria Syndrome (HGPS) is a fatal genetic disorder characterized by premature aging in multiple organs including the skin, musculoskeletal and cardiovascular systems. It is believed that an increased mechanosensitivity of HGPS cells is a causative factor for vascular cell death and vascular diseases in HGPS patients. However, the exact mechanism is unknown. Transient receptor potential (TRP) channels are cationic channels that can act as cellular sensors for mechanical stimuli. The aim of this present study was to examine the expression and functional role of TRP channels in human induced pluripotent stem cell-derived endothelial cells (iPSC-ECs) from the patients with HGPS. The mRNA and protein expression of TRP channels in HGPS and control (IMR90) iPSC-ECs were examined by semi-quantitative RT-PCRs and immunoblots, respectively. Hypotonicity-induced cytosolic Ca²⁺ ([Ca²⁺](i)) rise in iPSC-ECs was measured by confocal microscopy. RT-PCRs and immunoblots showed higher expressional levels of TRPV2 in iPSC-ECs from HGPS patients than those from normal individuals. In functional studies, hypotonicity induced a transient [Ca²⁺](i) rise in iPSC-ECs from normal individuals but a sustained [Ca²⁺](i) elevation in iPSC-ECs from HGPS patients. A nonselective TRPV inhibitor, ruthenium red (RuR, 20 µM), and a specific TRPV2 channel inhibitor, tranilast (100 µM), abolished the sustained phase of hypotonicity-induced [Ca²⁺](i) rise in iPSC-ECs from HGPS patients, and also markedly attenuated the transient phase of the [Ca²⁺](i) rise in these cells. Importantly, a short 10 min hypotonicity treatment caused a substantial increase in caspase 8 activity in iPSC-ECs from HGPS patients but not in cells from normal individuals. Tranilast could also inhibit the hypotonicity-induced increase in caspase 8 activity. Taken together, our data suggest that an up-regulation in TRPV2 expression causes a sustained [Ca²⁺](i) elevation in HGPS

  4. 42 CFR 424.84 - Final determination on revocation of right to receive assigned benefits.

    Science.gov (United States)

    2010-10-01

    ... receive assigned benefits. (a) Basis of final determination—(1) Final determination without a hearing. If... 42 Public Health 3 2010-10-01 2010-10-01 false Final determination on revocation of right to receive assigned benefits. 424.84 Section 424.84 Public Health CENTERS FOR MEDICARE & MEDICAID...

  5. The First Six ALMA Band 10 Receivers

    Science.gov (United States)

    Fujii, Y.; Gonzalez, A.; Kroug, M.; Kaneko, K.; Miyachi, A.; Yokoshima, T.; Kuroiwa, K.; Ogawa, H.; Makise, K.; Wang, Z.; Uzawa, Y.

    2013-01-01

    The first six Atacama Large Millimeter/submillimeter Array (ALMA) Band 10 (787-950 GHz) receivers have been developed and characterized during the receiver preproduction phase. State-of-the-art measurement systems at THz frequencies have been implemented and successfully used to measure the performance of the first six receivers. Extensive tests ranging from receiver sensitivity and stability to optical aperture efficiency on the secondary antenna have been performed. Performance of all six receivers is well within the stringent ALMA requirements. Moreover, our extensive tests have shown that there are no big performance differences between receivers. These results indicate that the ALMA Band 10 receiver is ready for the production phase, during which an additional 67 receivers will be produced and characterized.

  6. Trough Receiver Heat Loss Testing (Presentation)

    Energy Technology Data Exchange (ETDEWEB)

    Lewandowski, A.; Feik, C.; Hansen, R.; Phillips, S.; Bingham, C.; Netter, J.; Forristal, R.; Burkholder, F.; Meglan, B.; Wolfrum, E.

    2006-02-01

    This presentation describes the design, fabrication, and qualification of an experimental capability for thermal loss testing of full-size trough receiver elements; and the testing on a variety of receivers.

  7. Children's cancer centers

    Science.gov (United States)

    Pediatric cancer center; Pediatric oncology center; Comprehensive cancer center ... Treating childhood cancer is not the same as treating adult cancer. The cancers are different. So are the treatments and the ...

  8. Transplant Center Search Form

    Science.gov (United States)

    ... Share Your Story Give Us Feedback - A + A Transplant Center Search Form Welcome to the Blood & Marrow ... transplant centers for patients with a particular disease. Transplant Center login Username: * Password: * Request new password Join ...

  9. The Watergate Learning Center

    Science.gov (United States)

    Training in Business and Industry, 1971

    1971-01-01

    The Watergate Learning Center, recently opened by Sterling Learning Center in Washington, D. C., blueprints the plan established by Sterling and Marriott Hotels for a national chain of learning centers with much the same facilities. (EB)

  10. 49 CFR 236.730 - Coil, receiver.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Coil, receiver. 236.730 Section 236.730 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Coil, receiver. Concentric layers of insulated wire wound around the core of a receiver of an...

  11. 49 CFR 393.88 - Television receivers.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 5 2010-10-01 2010-10-01 false Television receivers. 393.88 Section 393.88... NECESSARY FOR SAFE OPERATION Miscellaneous Parts and Accessories § 393.88 Television receivers. Any motor vehicle equipped with a television viewer, screen or other means of visually receiving a...

  12. Southern California Particle Center

    Data.gov (United States)

    Federal Laboratory Consortium — At the Southern California Particle Center, center researchers will investigate the underlying mechanisms that produce the health effects associated with exposure to...

  13. Womens Business Center

    Data.gov (United States)

    Small Business Administration — Women's Business Centers (WBCs) represent a national network of nearly 100 educational centers throughout the United States and its territories, which are designed...

  14. A zero-power radio receiver.

    Energy Technology Data Exchange (ETDEWEB)

    Brocato, Robert Wesley

    2004-09-01

    This report describes both a general methodology and some specific examples of passive radio receivers. A passive radio receiver uses no direct electrical power but makes sole use of the power available in the radio spectrum. These radio receivers are suitable as low data-rate receivers or passive alerting devices for standard, high power radio receivers. Some zero-power radio architectures exhibit significant improvements in range with the addition of very low power amplifiers or signal processing electronics. These ultra-low power radios are also discussed and compared to the purely zero-power approaches.

  15. An SDR based AIS receiver for satellites

    DEFF Research Database (Denmark)

    Larsen, Jesper Abildgaard; Mortensen, Hans Peter; Nielsen, Jens Frederik Dalsgaard

    2011-01-01

    For a few years now, there has been a high interest in monitoring the global ship traffic from space. A few satellite, capable of listening for ship borne AIS transponders have already been launched, and soon the AAUSAT3, carrying two different types of AIS receivers will also be launched. One...... of the AIS receivers onboard AAUSAT3 is an SDR based AIS receiver. This paper serves to describe the background of the AIS system, and how the SDR based receiver has been integrated into the AAUSAT3 satellite. Amongst some of the benefits of using an SDR based receiver is, that due to its versatility, new...

  16. 42 CFR 435.322 - Medically needy coverage of the blind in States that cover individuals receiving SSI.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 4 2010-10-01 2010-10-01 false Medically needy coverage of the blind in States that cover individuals receiving SSI. 435.322 Section 435.322 Public Health CENTERS FOR MEDICARE... individuals receiving SSI. If the agency provides Medicaid to individuals receiving SSI and elects to cover...

  17. 42 CFR 435.320 - Medically needy coverage of the aged in States that cover individuals receiving SSI.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 4 2010-10-01 2010-10-01 false Medically needy coverage of the aged in States that cover individuals receiving SSI. 435.320 Section 435.320 Public Health CENTERS FOR MEDICARE & MEDICAID... individuals receiving SSI. If the agency provides Medicaid to individuals receiving SSI and elects to cover...

  18. 42 CFR 435.324 - Medically needy coverage of the disabled in States that cover individuals receiving SSI.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 4 2010-10-01 2010-10-01 false Medically needy coverage of the disabled in States that cover individuals receiving SSI. 435.324 Section 435.324 Public Health CENTERS FOR MEDICARE... individuals receiving SSI. If the agency provides Medicaid to individuals receiving SSI and elects to cover...

  19. Astronomical Receiver Modelling Using Scattering Matrices

    CERN Document Server

    King, O G; Copley, C; Davis, R J; Leahy, J P; Leech, J; Muchovej, S J C; Pearson, T J; Taylor, Angela C

    2014-01-01

    Proper modelling of astronomical receivers is vital: it describes the systematic errors in the raw data, guides the receiver design process, and assists data calibration. In this paper we describe a method of analytically modelling the full signal and noise behaviour of arbitrarily complex radio receivers. We use electrical scattering matrices to describe the signal behaviour of individual components in the receiver, and noise correlation matrices to describe their noise behaviour. These are combined to produce the full receiver model. We apply this approach to a specified receiver architecture: a hybrid of a continous comparison radiometer and correlation polarimeter designed for the C-Band All-Sky Survey. We produce analytic descriptions of the receiver Mueller matrix and noise temperature, and discuss how imperfections in crucial components affect the raw data. Many of the conclusions drawn are generally applicable to correlation polarimeters and continuous comparison radiometers.

  20. Taiyuan Satellite Launch Center

    Institute of Scientific and Technical Information of China (English)

    LiuJie

    2004-01-01

    There are three major space launch bases in China, the Jiuquan Satellite Launch Center,the Taiyuan Satellite Launch Center and the Xichang Satellite Launch Center. All the three launch centers are located in sparsely populated areas where the terrain is even and the field of vision is broad. Security, transport conditions and the influence of the axial rotation

  1. Student Success Center Toolkit

    Science.gov (United States)

    Jobs For the Future, 2014

    2014-01-01

    "Student Success Center Toolkit" is a compilation of materials organized to assist Student Success Center directors as they staff, launch, operate, and sustain Centers. The toolkit features materials created and used by existing Centers, such as staffing and budgeting templates, launch materials, sample meeting agendas, and fundraising…

  2. High stable remote photoelectric receiver for interferometry

    Science.gov (United States)

    Yang, Hongxing; Zhu, Pengfei; Tan, Jiubin; Hu, Pengcheng; Fan, Zhigang

    2017-03-01

    A high sensitive and high stable remote photoelectric receiver has been developed to reduce noise and phase delay drift caused by thermal pollution and environmental interference. The phase delay drift model is analyzed and built based on a traditional photoelectric receiver. According to the model, a new mechanical isolation structure and a temperature control system are designed to keep the photoelectric receiver in a low constant temperature. Comparison experiments with traditional bias voltage compensation method and temperature control method are carried out between photoelectric receivers. The results verify that the output voltage fluctuation of photoelectric receiver used is reduced by 65% while the phase drift between measurement and reference photoelectric receivers decreases from 1.05° to 0.02°.

  3. Analysis of the omnium-g receiver

    Energy Technology Data Exchange (ETDEWEB)

    Bohn, M.

    1980-03-01

    A thermal analysis of the Omnium-G receiver is presented and the technique is shown to be generally applicable to solar thermal receivers utilizing a directly heated thermal mass. The thermal loss coefficient, including reradiation losses, is calculated and shown to agree quite well with the experimentally measured thermal loss coefficient. The rate of heat transfer to the working fluid is also analyzed and the analysis is used to show that the Omnium-G receiver is well matched to the water/steam working fluid because the steam outlet temperature is almost the same as the receiver temperature. A general procedure for calculating receiver performance is presented. With this procedure, the energy delivery to any working fluid, the delivered temperature of the working fluid, and the pressure drop through the receiver can be determined. An example of the calculation is also presented.

  4. 150 Years of Blowing: Since John Hutchinson

    Directory of Open Access Journals (Sweden)

    Joseph Milic-Emili

    1997-01-01

    Full Text Available Three recent advances in assessment of routine lung function are reviewed. In both normal subjects and patients with obstructive lung disease, the flows during the forced vital capacity (FVC manoeuvre depend significantly on the pattern of the preceding inspiratory manoeuvre. Accordingly, the latter should be standardized in clinical and epidemiological studies. Although the nature of this phenomenon is not fully understood, stress relaxation of lung tissues probably plays the primary role. The negative expiratory pressure technique provides a simple and reliable tool for detecting expiratory flow limitation both at rest and during exercise. The method does not require body plethysmography or the patient’s cooperation and coordination, and can be applied in any desired body posture. A simple method for monitoring FVC performance has been developed. It allows detection of flow limitation during the FVC manoeuvre.

  5. Concentrated solar power generation using solar receivers

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, Bruce N.; Treece, William Dean; Brown, Dan; Bennhold, Florian; Hilgert, Christoph

    2017-08-08

    Inventive concentrated solar power systems using solar receivers, and related devices and methods, are generally described. Low pressure solar receivers are provided that function to convert solar radiation energy to thermal energy of a working fluid, e.g., a working fluid of a power generation or thermal storage system. In some embodiments, low pressure solar receivers are provided herein that are useful in conjunction with gas turbine based power generation systems.

  6. Determinants of survival in patients receiving dialysis in Libya.

    Science.gov (United States)

    Alashek, Wiam A; McIntyre, Christopher W; Taal, Maarten W

    2013-04-01

    Maintenance dialysis is associated with reduced survival when compared with the general population. In Libya, information about outcomes on dialysis is scarce. This study, therefore, aimed to provide the first comprehensive analysis of survival in Libyan dialysis patients. This prospective multicenter study included all patients in Libya who had been receiving dialysis for >90 days in June 2009. Sociodemographic and clinical data were collected upon enrollment and survival status after 1 year was determined. Two thousand two hundred seventy-three patients in 38 dialysis centers were followed up for 1 year. The majority were receiving hemodialysis (98.8%). Sixty-seven patients were censored due to renal transplantation, and 46 patients were lost to follow-up. Thus, 2159 patients were followed up for 1 year. Four hundred fifty-eight deaths occurred, (crude annual mortality rate of 21.2%). Of these, 31% were due to ischemic heart disease, 16% cerebrovascular accidents, and 16% due to infection. Annual mortality rate was 0% to 70% in different dialysis centers. Best survival was in age group 25 to 34 years. Binary logistic regression analysis identified age at onset of dialysis, physical dependency, diabetes, and predialysis urea as independent determinants of increased mortality. Patients receiving dialysis in Libya have a crude 1-year mortality rate similar to most developed countries, but the mean age of the dialysis population is much lower, and this outcome is thus relatively poor. As in most countries, cardiovascular disease and infection were the most common causes of death. Variation in mortality rates between different centers suggests that survival could be improved by promoting standardization of best practice.

  7. Shipping/Receiving and Quality Control

    Data.gov (United States)

    Federal Laboratory Consortium — Shipping receiving, quality control, large and precise inspection and CMM machines. Coordinate Measuring Machines, including "scanning" probes, optical comparators,...

  8. Efficient structures for wideband digital receiver

    Institute of Scientific and Technical Information of China (English)

    Wang Hong; Lu Youxin; Wang Xuegang; Wan Yonglun

    2006-01-01

    Digital receivers have become more and more popular in radar, communication, and electric warfare for the advantages compared with their analog counterparts. But conventional digital receivers have been generally considered impractical for bandwidth greater than several hundreds MHz. To extend receiver bandwidth, decrease data rate and save hardware resources, three novel structures are proposed. They decimate the data stream prior to mixing and filtering, then process the multiple decimated streams in parallel at a lower rate. Consequently it is feasible to realize wideband receivers on the current ASIC devices. A design example and corresponding simulation results are demonstrated to evaluate the proposed structures.

  9. Receiver function estimated by maximum entropy deconvolution

    Institute of Scientific and Technical Information of China (English)

    吴庆举; 田小波; 张乃铃; 李卫平; 曾融生

    2003-01-01

    Maximum entropy deconvolution is presented to estimate receiver function, with the maximum entropy as the rule to determine auto-correlation and cross-correlation functions. The Toeplitz equation and Levinson algorithm are used to calculate the iterative formula of error-predicting filter, and receiver function is then estimated. During extrapolation, reflective coefficient is always less than 1, which keeps maximum entropy deconvolution stable. The maximum entropy of the data outside window increases the resolution of receiver function. Both synthetic and real seismograms show that maximum entropy deconvolution is an effective method to measure receiver function in time-domain.

  10. Nursing process approach improves receivables management.

    Science.gov (United States)

    Dias, K; Stockamp, D

    1992-09-01

    The "nursing process" is a systematic decision-making approach to problem solving based on open-system theory. This theory assumes that there is an on-going interchange between all system components. Components cannot be viewed in isolation, because decisions regarding one component will affect other components. Receivables management is similar to the nursing process, in that it involves constant diagnosis, assessment, and intervention in the work in process during all phases of the receivables cycle. In experiments that applied the nursing process concept to the management of accounts receivable in several hospitals, gross days in accounts receivable were reduced and cash flow was increased.

  11. Special design topics in digital wideband receivers

    CERN Document Server

    Tsui, James B Y

    2009-01-01

    Offering engineers a thorough examination of special, more advanced aspects of digital wideband receiver design, this practical book builds on fundamental resources on the topic, helping you gain a more comprehensive understanding of the subject. This in-depth volume presents a detailed look at a complete receiver design, including the encoder. Moreover, it discusses the detection of exotic signals and provides authoritative guidance on designing receivers used in electronic warfare. From frequency modulation and biphase shifting keys, to parameter encoders in electronic warfare receivers and

  12. Adaptive beamforming and phase bias compensation for GNSS receiver

    Institute of Scientific and Technical Information of China (English)

    Hongwei Zhao; Baowang Lian; Juan Feng

    2015-01-01

    Adaptive antenna arrays have been used to mitigate the interference on global navigation satel ite system (GNSS) re-ceivers. The performance of interference mitigation depends on the beamforming algorithms adopted by the antenna array. However, the adaptive beamforming wil change the array pattern in real-time, which has the potential to introduce phase center biases into the antenna array. For precise applications, these phase biases must be mitigated or compensated because they wil bring errors in code phase and carrier phase measurements. A novel adaptive beamforming algorithm is proposed firstly, then the phase bias induced by the proposed algorithm is estimated, and final y a com-pensation strategy is addressed. Simulations demonstrate that the proposed beamforming algorithm suppresses effectively the strong interference and improves significantly the capturing performance of GNSS signals. Simultaneously, the bias compensation method avoids the loss of the carrier phase lock and reduces the phase measurement errors for GNSS receivers.

  13. Reactivation of latently infected HIV-1 viral reservoirs and correction of aberrant alternative splicing in the LMNA gene via AMPK activation: Common mechanism of action linking HIV-1 latency and Hutchinson-Gilford progeria syndrome.

    Science.gov (United States)

    Finley, Jahahreeh

    2015-09-01

    Although the use of antiretroviral therapy (ART) has proven highly effective in controlling and suppressing HIV-1 replication, the persistence of latent but replication-competent proviruses in a small subset of CD4(+) memory T cells presents significant challenges to viral eradication from infected individuals. Attempts to eliminate latent reservoirs are epitomized by the 'shock and kill' approach, a strategy involving the combinatorial usage of compounds that influence epigenetic modulation and initiation of proviral transcription. However, efficient regulation of viral pre-mRNA splicing through manipulation of host cell splicing machinery is also indispensible for HIV-1 replication. Interestingly, aberrant alternative splicing of the LMNA gene via the usage of a cryptic splice site has been shown to be the cause of most cases of Hutchinson-Gilford progeria syndrome (HGPS), a rare genetic condition characterized by an accelerated aging phenotype due to the accumulation of a truncated form of lamin A known as progerin. Recent evidence has shown that inhibition of the splicing factors ASF/SF2 (or SRSF1) and SRp55 (or SRSF6) leads to a reduction or an increase in progerin at both the mRNA and protein levels, respectively, thus altering the LMNA pre-mRNA splicing ratio. It is also well-established that during the latter stages of HIV-1 infection, an increase in the production and nuclear export of unspliced viral mRNA is indispensible for efficient HIV-1 replication and that the presence of ASF/SF2 leads to excessive viral pre-mRNA splicing and a reduction of unspliced mRNA, while the presence of SRp55 inhibits viral pre-mRNA splicing and aids in the generation and translation of unspliced HIV-1 mRNAs. The splicing-factor associated protein and putative mitochondrial chaperone p32 has also been shown to inhibit ASF/SF2, increase unspliced HIV-1 viral mRNA, and enhance mitochondrial DNA replication and oxidative phosphorylation. It is our hypothesis that activation of

  14. Variable velocity in solar external receivers

    Science.gov (United States)

    Rodríguez-Sánchez, M. R.; Sánchez-González, A.; Acosta-Iborra, A.; Santana, D.

    2017-06-01

    One of the major problems in solar external receivers is tube overheating, which accelerates the risk of receiver failure. It can be solved implementing receivers with high number of panels. However, it exponentially increases the pressure drop in the receiver and the parasitic power consumption of the Solar Power Tower (SPT), reducing the global efficiency of the SPT. A new concept of solar external receiver, named variable velocity receiver, is able to adapt their configuration to the different flux density distributions. A set of valves allows splitting in several independent panels those panels in which the wall temperature is over the limit. It increases the velocity of the heat transfer fluid (HTF) and its cooling capacity. This receiver does not only reduce the wall temperature of the tubes, but also simplifies the control of the heliostat field and allows to employ more efficient aiming strategies. In this study, it has been shown that variable velocity receiver presents high advantages with respect to traditional receiver. Nevertheless, more than two divisions per panels are not recommendable, due to the increment of the pressure drop over 70 bars. In the design point (12 h of the Spring Equinox), the use of a variable number of panels between 18 and 36 (two divisions per panel), in a SPT similar to Gemasolar, improves the power capacity of the SPT in 5.7%, with a pressure drop increment of 10 bars. Off-design, when the flux distribution is high and not symmetric (e.g. 10-11 h), the power generated by the variable velocity receiver is 18% higher than the generated by the traditional receiver, at these hours the pressure drop increases almost 20 bars.

  15. Design and implementation of the CAPS receiver

    Science.gov (United States)

    Hu, Yonghui; Hua, Yu; Hou, Lei; Wei, Jingfa; Wu, Jianfeng

    2009-03-01

    In this paper, based on analyses of the Chinese Area Positioning System (CAPS) satellite (GEO satellite) resources and signal properties, the signal power at the port of the receiver antenna is estimated, and the implementation projects are presented for a switching band C to band L CAPS C/A code receiver integrated with GPS receiver suite and for a CAPS dual frequency P code receiver. A microstrip receiving antenna is designed with high sensitivity and wide beam orientation, the RF front end of the C/A code and P code receivers, and a processor is designed for the navigation baseband. A single frequency CAPS C/A code receiver and a CAPS dual frequency P code receiver are built at the same time. A software process flow is provided, and research on relatively key techniques is also conducted, such as signal searching, code loop and carrier loop algorithms, a height assistant algorithm, a dual frequency difference speed measurement technique, a speed measurement technique using a single frequency source with frequency assistance, and a CAPS time correcting algorithm, according to the design frame of the receiver hardware. Research results show that the static plane positioning accuracy of the CAPS C/A code receiver is 20.5-24.6 m, height accuracy is 1.2-12.8 m, speed measurement accuracy is 0.13-0.3 m/s, dynamic plane positioning accuracy is 24.4 m, height accuracy is 3.0 m, and speed measurement accuracy is 0.24 m/s. In the case of C/A code, the timing accuracy is 200 ns, and it is also shown that the positioning accuracy of the CAPS precise code receiver (1 σ) is 5 m from south to north, and 0.8 m from east to west. Finally, research on positioning accuracy is also conducted.

  16. Design and implementation of the CAPS receiver

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    In this paper, based on analyses of the Chinese Area Positioning System (CAPS) satellite (GEO satellite) resources and signal properties, the signal power at the port of the receiver antenna is estimated, and the implementation projects are presented for a switching band C to band L CAPS C/A code receiver integrated with GPS receiver suite and for a CAPS dual frequency P code receiver. A microstrip receiving antenna is designed with high sensitivity and wide beam orientation, the RF front end of the C/A code and P code receivers, and a processor is designed for the navigation baseband. A single frequency CAPS C/A code receiver and a CAPS dual frequency P code receiver are built at the same time. A software process flow is provided, and research on relatively key techniques is also conducted, such as signal searching, code loop and carrier loop algorithms, a height assistant algorithm, a dual frequency difference speed measurement technique, a speed measurement technique using a single frequency source with frequency assistance, and a CAPS time correcting algorithm, according to the design frame of the receiver hardware. Research results show that the static plane positioning accuracy of the CAPS C/A code receiver is 20.5-24.6 m, height accuracy is 1.2-12.8 m, speed measurement accuracy is 0.13-0.3 m/s, dynamic plane positioning accuracy is 24.4 m, height accuracy is 3.0 m, and speed measurement accuracy is 0.24 m/s. In the case of C/A code, the timing accuracy is 200 ns, and it is also shown that the positioning accuracy of the CAPS precise code receiver (1σ ) is 5 m from south to north, and 0.8 m from east to west. Finally, research on positioning accuracy is also conducted.

  17. Superconducting integrated submillimeter receiver for TELIS

    NARCIS (Netherlands)

    Koshelets, Valery P.; Ermakov, Andrey B.; Filippenko, Lyudmila V.; Khudchenko, Andrey V.; Kiselev, Oleg S.; Sobolev, Alexander S.; Torgashin, Mikhail Yu.; Yagoubov, Pavel A.; Hoogeveen, Ruud W. M.; Wild, Wolfgang

    2007-01-01

    In this report an overview of the results on the development of a single-chip superconducting integrated receiver for the Terahertz Limb Sounder (TELIS) balloon project intended to measure a variety of stratosphere trace gases is presented. The Superconducting Integrated Receiver (SIR) comprises in

  18. 47 CFR 32.1170 - Receivables.

    Science.gov (United States)

    2010-10-01

    ... FOR TELECOMMUNICATIONS COMPANIES Instructions for Balance Sheet Accounts § 32.1170 Receivables. (a... enable the company to make the following analysis: (1) Amounts due from customers who are receiving... process of collection. (b) Collections in excess of amounts charged to this account may be credited to...

  19. Superconducting chip receivers for imaging application

    NARCIS (Netherlands)

    Shitov, SV; Koshelets, VP; Ermakov, AB; Filippenko, LV; Baryshev, AM; Luinge, W; Gao, [No Value

    1999-01-01

    Experimental details of a unique superconducting imaging array receiver are discussed. Each pixel contains an internally pumped receiver chip mounted on the back of the elliptical microwave lens. Each chip comprises a quasi-optical SIS mixer integrated with a superconducting flux-flow oscillator (FF

  20. Social networks and receiving informal care.

    NARCIS (Netherlands)

    Boer, A. de; Klerk, M. de; Cardol, M.; Westert, G.

    2006-01-01

    In 2001, roughly half a million people (4% of the Dutch population) received informal care from family members living outside their home, and a quarter of a million (2% of the Dutch population) received this care from acquaintances, such as friend, neighbours and work colleagues. The potential suppl

  1. 21 CFR 1020.10 - Television receivers.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Television receivers. 1020.10 Section 1020.10 Food...) RADIOLOGICAL HEALTH PERFORMANCE STANDARDS FOR IONIZING RADIATION EMITTING PRODUCTS § 1020.10 Television receivers. (a) Applicability. The provisions of this section are applicable to television...

  2. RF performance of T-DAB receivers

    NARCIS (Netherlands)

    Schiphorst, R.; Potman, J.; Hofstra, K.L.; Cronie, H.S.; Slump, C.H.

    2008-01-01

    In every wireless system, the weakest link determines the performance of the network. In this paper the Radio Frequency (RF) performance of both band III and L-band Terrestrial Digital Audio Broadcasting (T-DAB) consumer receivers are discussed. The receivers have been tested based on the EN 50248 s

  3. Compressive Sensing for Spread Spectrum Receivers

    DEFF Research Database (Denmark)

    Fyhn, Karsten; Jensen, Tobias Lindstrøm; Larsen, Torben

    2013-01-01

    With the advent of ubiquitous computing there are two design parameters of wireless communication devices that become very important: power efficiency and production cost. Compressive sensing enables the receiver in such devices to sample below the Shannon-Nyquist sampling rate, which may lead...... to a decrease in the two design parameters. This paper investigates the use of Compressive Sensing (CS) in a general Code Division Multiple Access (CDMA) receiver. We show that when using spread spectrum codes in the signal domain, the CS measurement matrix may be simplified. This measurement scheme, named...... Compressive Spread Spectrum (CSS), allows for a simple, effective receiver design. Furthermore, we numerically evaluate the proposed receiver in terms of bit error rate under different signal to noise ratio conditions and compare it with other receiver structures. These numerical experiments show that though...

  4. High dynamic, low volume GPS receiver

    Science.gov (United States)

    Hurd, W. J.

    1983-01-01

    A new GPS receiver concept and design are presented to meet the high dynamic and low volume requirements for range applications in missiles and drones. The receiver has the potential to satisfy all range requirements with one basic receiver, which has significant potential economic benefit over the alternate approach of using a family of receivers, each tailored for specific applications. The main new concept is to use approximate maximum likelihood estimates of pseudo range and range-rate, rather than tracking with carrier phase locked loops and code delay locked loops. Preliminary analysis indicates that receivers accelerating at 50 g or more can track with position errors due to acceleration of approximately 0.2 m/g, or 10 m at 50 g. Implementation is almost entirely digital to meet the low volume requirements.

  5. An SDR based AIS receiver for satellites

    DEFF Research Database (Denmark)

    Larsen, Jesper Abildgaard; Mortensen, Hans Peter; Nielsen, Jens Frederik Dalsgaard

    2011-01-01

    For a few years now, there has been a high interest in monitoring the global ship traffic from space. A few satellite, capable of listening for ship borne AIS transponders have already been launched, and soon the AAUSAT3, carrying two different types of AIS receivers will also be launched. One...... of the AIS receivers onboard AAUSAT3 is an SDR based AIS receiver. This paper serves to describe the background of the AIS system, and how the SDR based receiver has been integrated into the AAUSAT3 satellite. Amongst some of the benefits of using an SDR based receiver is, that due to its versatility, new...... detection algorithms are easily deployed, and it is easily adapted the new proposed AIS transmission channels....

  6. Poison Control Centers

    Science.gov (United States)

    ... 1222 immediately. Name State American Association of Poison Control Centers Address AAPCC Central Office NOT A POISON ... not for emergency use. Arkansas ASPCA Animal Poison Control Center Address 1717 S. Philo Road, Suite 36 Urbana, ...

  7. RSW Cell Centered Grids

    Data.gov (United States)

    National Aeronautics and Space Administration — New cell centered grids are generated to complement the node-centered ones uploaded. Six tarballs containing the coarse, medium, and fine mixed-element and pure tet....

  8. MARYLAND ROBOTICS CENTER

    Data.gov (United States)

    Federal Laboratory Consortium — The Maryland Robotics Center is an interdisciplinary research center housed in the Institute for Systems Research (link is external) within the A. James Clark School...

  9. NIH Clinical Centers

    Data.gov (United States)

    Federal Laboratory Consortium — The NIH Clinical Center consists of two main facilities: The Mark O. Hatfield Clinical Research Center, which opened in 2005, houses inpatient units, day hospitals,...

  10. Automating the Media Center.

    Science.gov (United States)

    Holloway, Mary A.

    1988-01-01

    Discusses the need to develop more efficient information retrieval skills by the use of new technology. Lists four stages used in automating the media center. Describes North Carolina's pilot programs. Proposes benefits and looks at the media center's future. (MVL)

  11. National Rehabilitation Information Center

    Science.gov (United States)

    ... including News and Notes) Welcome to the National Rehabilitation Information Center! We are conducting improvements to the ... experience. We apologize for any inconvenience The National Rehabilitation Information Center ( NARIC ) is the library of the ...

  12. Day Care Centers

    Data.gov (United States)

    Department of Homeland Security — This database contains locations of day care centers for 50 states and Washington D.C. and Puerto Rico. The dataset only includes center based day care locations...

  13. Center for Functional Nanomaterials

    Data.gov (United States)

    Federal Laboratory Consortium — The Center for Functional Nanomaterials (CFN) explores the unique properties of materials and processes at the nanoscale. The CFN is a user-oriented research center...

  14. Hydrologic Engineering Center

    Data.gov (United States)

    Federal Laboratory Consortium — The Hydrologic Engineering Center (HEC), an organization within the Institute for Water Resources, is the designated Center of Expertise for the U.S. Army Corps of...

  15. Hydrologic Engineering Center

    Data.gov (United States)

    Federal Laboratory Consortium — The Hydrologic Engineering Center (HEC), an organization within the Institute for Water Resources, is the designated Center of Expertise for the U.S. Army Corps of...

  16. BKG Data Center

    Science.gov (United States)

    Thorandt, Volkmar; Wojdziak, Reiner

    2013-01-01

    This report summarizes the activities and background information of the IVS Data Center for the year 2012. Included is information about functions, structure, technical equipment, and staff members of the BKG Data Center.

  17. Find a Health Center

    Data.gov (United States)

    U.S. Department of Health & Human Services — HRSA Health Centers care for you, even if you have no health insurance – you pay what you can afford based on your income. Health centers provide services that...

  18. Center of Attention.

    Science.gov (United States)

    Coffey, J. Steven; Wood-Steed, Ruth

    2001-01-01

    Illustrates how college and university student centers are becoming the institution's marketing tools. Explores how the Millennium Center at the University of Missouri in St. Louis exemplifies this new trend. (GR)

  19. The Comprehensive Learning Center

    Science.gov (United States)

    Peterson, Gary T.

    1975-01-01

    This paper describes the results of a study of community college learning resource centers as they exist today and examines some emerging functions which point toward the role of the center in the future. (DC)

  20. Center for Women Veterans

    Science.gov (United States)

    ... Aid & Attendance & Housebound Caregivers Community Living Centers (CLC) Community Nursing Homes Domiciliaries (Please contact your local VA Medical Center) Homemaker & Home Health Aid Care Hospice and Palliative Care State Veterans ...

  1. Center for Functional Nanomaterials

    Data.gov (United States)

    Federal Laboratory Consortium — The Center for Functional Nanomaterials (CFN) explores the unique properties of materials and processes at the nanoscale. The CFN is a user-oriented research center...

  2. MARYLAND ROBOTICS CENTER

    Data.gov (United States)

    Federal Laboratory Consortium — The Maryland Robotics Center is an interdisciplinary research center housed in the Institute for Systems Research (link is external)within the A. James Clark School...

  3. Comparison of baseline results for the TI-4100 and Trimble 4000SDT geodetic GPS receivers

    Science.gov (United States)

    Freymueller, Jeffrey T.

    1992-10-01

    Many GPS networks which were initially surveyed with Texas Instruments TI-4100 receivers have now been resurveyed with mixtures of TI-4100 and Trimble 4000 receivers or exclusively with Trimble receivers. In order to make confident tectonic interpretation of displacements observed between such surveys, it is necessary to understand any biases which may be introduced by using different receiver types or by mixing receivers within a network. Therefore, one of the primary objectives of the Ecuador 1990 GPS campaign (February 1990) was to provide a direct long baseline comparison between the TI-4100 and Trimble 4000SDT GPS receivers. p ]During this campaign, TI and Trimble receivers were co-located at each end of a 1323 kilometer baseline (Jerusalen to Baltra). Solutions for this baseline show no variation with receiver type. Zero-length baseline solutions showed no evidence for any intrinsic bias caused by mixing the two receiver types. Short baseline solutions indicate a bias of -34±10 mm in the baseline vertical component; the sign of the bias indicates that either the assumed phase center location for the TI is too low or the assumed location for the Trimble is too high. The bias is explainable if the phase centers of the Trimble SDT and SST antennas are similarly located. p ]Solutions for baselines measured with codeless receivers (such as the Trimble) should be as precise as those for baselines measured with P-code receivers (such as the TI) as long as it is possible to resolve ambiguities. Resolution of the widelane ambiguity is the limiting factor in ambiguity resolution with any codeless receiver, and in the February 1990 campaigns it was not successful fore baselines longer than 100 km. Without explicit modeling of the ionospheric effect on the widelane, ambiguity resolution with codeless receivers will not be successful for baselines longer than about 100 km, depending on the local ionospheric conditions.

  4. Enhanced AIS receiver design for satellite reception

    Science.gov (United States)

    Clazzer, Federico; Lázaro, Francisco; Plass, Simon

    2016-12-01

    The possibility to detect Automatic Identification System (AIS) messages from low earth orbit (LEO) satellites paves the road for a plurality of new and unexplored services. Besides worldwide tracking of vessels, maritime traffic monitoring, analysis of vessel routes employing big data, and oceans monitoring are just few of the fields, where satellite-aided AIS is beneficial. Designed for ship-to-ship communication and collision avoidance, AIS satellite reception performs poorly in regions with a high density of vessels. This calls for the development of advanced satellite AIS receivers able to improve the decoding capabilities. In this context, our contribution focuses on the introduction of a new enhanced AIS receiver design and its performance evaluation. The enhanced receiver makes use of a coherent receiver for the low signal-to-noise ratio (SNR) region, while for medium to high SNRs, a differential Viterbi receiver is used. Additional novelty of our work is in the exploitation of previously decoded packets from one vessel that is still under the LEO reception range, to improve the vessel detection probability. The assessment of the performance against a common receiver is done making the use of a simple and tight model of the medium access (MAC) layer and the multi-packet reception (MPR) matrix for physical layer (PHY) representation. Performance results show the benefits of such enhanced receiver, especially when it is bundled with successive interference cancellation (SIC).

  5. Terahertz Array Receivers with Integrated Antennas

    Science.gov (United States)

    Chattopadhyay, Goutam; Llombart, Nuria; Lee, Choonsup; Jung, Cecile; Lin, Robert; Cooper, Ken B.; Reck, Theodore; Siles, Jose; Schlecht, Erich; Peralta, Alessandro; Thomas, Bertrand; Mehdi, Imran

    2011-01-01

    Highly sensitive terahertz heterodyne receivers have been mostly single-pixel. However, now there is a real need of multi-pixel array receivers at these frequencies driven by the science and instrument requirements. In this paper we explore various receiver font-end and antenna architectures for use in multi-pixel integrated arrays at terahertz frequencies. Development of wafer-level integrated terahertz receiver front-end by using advanced semiconductor fabrication technologies has progressed very well over the past few years. Novel stacking of micro-machined silicon wafers which allows for the 3-dimensional integration of various terahertz receiver components in extremely small packages has made it possible to design multi-pixel heterodyne arrays. One of the critical technologies to achieve fully integrated system is the antenna arrays compatible with the receiver array architecture. In this paper we explore different receiver and antenna architectures for multi-pixel heterodyne and direct detector arrays for various applications such as multi-pixel high resolution spectrometer and imaging radar at terahertz frequencies.

  6. Fundamentals of GPS Receivers A Hardware Approach

    CERN Document Server

    Doberstein, Dan

    2012-01-01

    While much of the current literature on GPS receivers is aimed at those intimately familiar with their workings, this volume summarizes the basic principles using as little mathematics as possible, and details the necessary specifications and circuits for constructing a GPS receiver that is accurate to within 300 meters. Dedicated sections deal with the features of the GPS signal and its data stream, the details of the receiver (using a hybrid design as exemplar), and more advanced receivers and topics including time and frequency measurements. Later segments discuss the Zarlink GPS receiver chip set, as well as providing a thorough examination of the TurboRogue receiver, one of the most accurate yet made. Guiding the reader through the concepts and circuitry, from the antenna to the solution of user position, the book’s deployment of a hybrid receiver as a basis for discussion allows for extrapolation of the core ideas to more complex, and more accurate designs. Digital methods are used, but any analogue c...

  7. Temperature influences in receiver clock modelling

    Science.gov (United States)

    Wang, Kan; Meindl, Michael; Rothacher, Markus; Schoenemann, Erik; Enderle, Werner

    2016-04-01

    In Precise Point Positioning (PPP), hardware delays at the receiver site (receiver, cables, antenna, …) are always difficult to be separated from the estimated receiver clock parameters. As a result, they are partially or fully contained in the estimated "apparent" clocks and will influence the deterministic and stochastic modelling of the receiver clock behaviour. In this contribution, using three years of data, the receiver clock corrections of a set of high-precision Hydrogen Masers (H-Masers) connected to stations of the ESA/ESOC network and the International GNSS Service (IGS) are firstly characterized concerning clock offsets, drifts, modified Allan deviations and stochastic parameters. In a second step, the apparent behaviour of the clocks is modelled with the help of a low-order polynomial and a known temperature coefficient (Weinbach, 2013). The correlations between the temperature and the hardware delays generated by different types of antennae are then analysed looking at daily, 3-day and weekly time intervals. The outcome of these analyses is crucial, if we intend to model the receiver clocks in the ground station network to improve the estimation of station-related parameters like coordinates, troposphere zenith delays and ambiguities. References: Weinbach, U. (2013) Feasibility and impact of receiver clock modeling in precise GPS data analysis. Dissertation, Leibniz Universität Hannover, Germany.

  8. Data center cooling method

    Energy Technology Data Exchange (ETDEWEB)

    Chainer, Timothy J.; Dang, Hien P.; Parida, Pritish R.; Schultz, Mark D.; Sharma, Arun

    2015-08-11

    A method aspect for removing heat from a data center may use liquid coolant cooled without vapor compression refrigeration on a liquid cooled information technology equipment rack. The method may also include regulating liquid coolant flow to the data center through a range of liquid coolant flow values with a controller-apparatus based upon information technology equipment temperature threshold of the data center.

  9. Should This Patient Receive an Antidepressant?: Grand Rounds Discussion From Beth Israel Deaconess Medical Center.

    Science.gov (United States)

    Burns, Risa B; Smetana, Gerald W; Brady, Roscoe

    2017-08-01

    Depression is a major public health problem and a common cause of disability. To help physicians choose among available treatment options, the American College of Physicians recently issued a guideline titled "Nonpharmacologic Versus Pharmacologic Treatment of Adult Patients with Major Depressive Disorder." The evidence review done for the guideline found no statistically significant difference in the efficacy of second-generation antidepressants (SGAs) versus most other treatments for this disorder. However, rates of adverse events and discontinuation were generally higher in patients treated with SGAs. This Beyond the Guidelines reviews the guideline and includes a discussion between 2 experts on how they would apply it to a 64-year-old man with depression who is reluctant to begin medication. They review the data on which the guideline is based, discuss the limitations of applying the data to real-world settings, review how they would incorporate patient preferences when making treatment decisions, and outline options for patients in whom first-line therapy has failed.

  10. New partnership between Virginia Tech Transportation Institute and Center for Injury Biomechanics receives first research grant

    OpenAIRE

    Box, Sherri

    2009-01-01

    A team of three Virginia Tech faculty members -- Stefan Duma, Warren Hardy, and H. Clay Gabler -- was recently awarded $2.6 million from U.S. Army Research Acquisition Activity to study the biomechanics of head, neck, and chest injury prevention for soldiers.

  11. Findings from Survey Administered to Weatherization Training Centers

    Energy Technology Data Exchange (ETDEWEB)

    Conlon, Brian [Univ. of Tennessee, Knoxville, TN (United States); Tonn, Bruce Edward [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-03-01

    This report summarizes results of a survey administered to directors of weatherization training centers that receive funding from the U.S. Department of Energy. The survey presents results related to questions on training offered and future plans.

  12. Advanced Receiver/Converter Experiments for Laser Wireless Power Transmission

    Science.gov (United States)

    Howell, Joe T.; ONeill, Mark; Fork, Richard

    2004-01-01

    For several years NASA Marshall Space Flight Center, UAH and ENTECH have been working on various aspects of space solar power systems. The current activity was just begun in January 2004 to further develop this new photovoltaic concentrator laser receiver/converter technology. During the next few months, an improved prototype will be designed, fabricated, and thoroughly tested under laser illumination. The final paper will describe the new concept, present its advantages over other laser receiver/converter approaches (including planar photovoltaic arrays), and provide the latest experiment results on prototype hardware (including the effects of laser irradiance level and cell temperature). With NASA's new human exploration plans to first return to the Moon, and then to proceed to Mars, the new photovoltaic concentrator laser receiver/converter technology could prove to be extremely useful in providing power to the landing sites and other phases of the missions. For example, to explore the scientifically interesting and likely resource-rich poles of the Moon (which may contain water) or the poles of Mars (which definitely contain water and carbon dioxide), laser power beaming could represent the simplest means of providing power to these regions, which receive little or no sunlight, making solar arrays useless there. In summary, the authors propose a paper on definition and experimental results of a novel photovoltaic concentrator approach for collecting and converting laser radiation to electrical power. The new advanced photovoltaic concentrator laser receiver/converter offers higher performance, lighter weight, and lower cost than competing concepts, and early experimental results are confirming the expected excellent Performance levels. After the small prototypes are successfully demonstrated, a larger array with even better performance is planned for the next phase experiments and demonstrations. Thereafter, a near-term flight experiment of the new technology

  13. Many southwest hosptials will receive decreased CMS reimbursement

    Directory of Open Access Journals (Sweden)

    Robbins RA

    2013-11-01

    Full Text Available No abstract available. Article truncated at 150 words. More hospitals are receiving penalties than bonuses in the second year of the Centers for Medicare and Medicaid Services’ (CMS quality incentive program, and the average penalty is steeper than last year according to a report from Jordan Rau in Kaiser Health News (1. Southwest hospitals reflect that trend with New Mexico and Arizona exceeding the US average both in percentage of hospitals receiving penalties and the average size of the penalty (Table 1. Colorado approximated the national averages (Table 1. Most hospitals are gaining or losing <0.2% but in some instances the penalties are substantial. Gallup Indian Medical Center in New Mexico, a federal government hospital on the border of the Navajo Reservation, will be paid 1.14 percent less for each patient and New Mexico’s average of a -0.31% decline in reimbursement are the largest changes nationally. “This program is driving what we want in health care,” said Dr. …

  14. Global Positioning System receiver evaluation results

    Energy Technology Data Exchange (ETDEWEB)

    Byrne, R.H.

    1993-09-01

    A Sandia project currently uses an outdated Magnavox 6400 Global Positioning System (GPS) receiver as the core of its navigation system. The goal of this study was to analyze the performance of the current GPS receiver compared to newer, less expensive models and to make recommendations on how to improve the performance of the overall navigation system. This paper discusses the test methodology used to experimentally analyze the performance of different GPS receivers, the test results, and recommendations on how an upgrade should proceed. Appendices contain detailed information regarding the raw data, test hardware, and test software.

  15. A call center primer.

    Science.gov (United States)

    Durr, W

    1998-01-01

    Call centers are strategically and tactically important to many industries, including the healthcare industry. Call centers play a key role in acquiring and retaining customers. The ability to deliver high-quality and timely customer service without much expense is the basis for the proliferation and expansion of call centers. Call centers are unique blends of people and technology, where performance indicates combining appropriate technology tools with sound management practices built on key operational data. While the technology is fascinating, the people working in call centers and the skill of the management team ultimately make a difference to their companies.

  16. List of Nuclear Materials Licensing Actions Received

    Data.gov (United States)

    Nuclear Regulatory Commission — A catalog of all Materials Licensing Actions received for review. The catalog lists the name of the entity submitting the license application, their city and state,...

  17. Metal Mesh Filters for Terahertz Receivers Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The best low-noise receiver solutions for frequencies above about 800 GHz rely on either a low-noise bolometric direct detector or a hot electron bolometric mixer....

  18. Metal Mesh Filters for Terahertz Receivers Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The technical objective of this SBIR program is to develop and demonstrate metal mesh filters for use in NASA's low noise receivers for terahertz astronomy and...

  19. 49 CFR 236.788 - Receiver.

    Science.gov (United States)

    2010-10-01

    ... OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Definitions § 236.788 Receiver. A device on a locomotive, so placed that it is in position to be influenced inductively or actuated by...

  20. Collector/Receiver Characterization (Fact Sheet)

    Energy Technology Data Exchange (ETDEWEB)

    2010-08-01

    Fact sheet describing NREL CSP Program capabilities for collector/receiver characterization: determining optical efficiency, measuring heat loss, developing and testing concentrators, concentrating the sun's power, and optically characterizing CSP plants.

  1. Digital Receiver for Laser Imaging Radar

    Institute of Scientific and Technical Information of China (English)

    WANG Wei Ran; SUN Bing

    2004-01-01

    With the extension of the application domains for laser imaging radar,it is necessary to find a new technical way to obtain high technical performance and adaptive ability.In this paper,A new concept of digital receiver of laser imaging radar system is presented.This digital receiver is defined as a time varying parameter receiver which possesses large dynamics region and time domain filter.The receiver's mode,component structure as well as every function of its processing are described.The results and laboratorial data show the feasibility of digital reception.Also,it can exploit the inherent nature of laser imaging radar to obtain high probability of detection.

  2. Optical Coherent Receiver Enables THz Wireless Bridge

    DEFF Research Database (Denmark)

    Yu, Xianbin; Liu, Kexin; Zhang, Hangkai

    2016-01-01

    We experimentally demonstrated a 45 Gbit/s 400 GHz photonic wireless communication system enabled by an optical coherent receiver, which has a high potential in fast recovery of high data rate connections, for example, in disaster....

  3. High dynamic GPS receiver validation demonstration

    Science.gov (United States)

    Hurd, W. J.; Statman, J. I.; Vilnrotter, V. A.

    1985-01-01

    The Validation Demonstration establishes that the high dynamic Global Positioning System (GPS) receiver concept developed at JPL meets the dynamic tracking requirements for range instrumentation of missiles and drones. It was demonstrated that the receiver can track the pseudorange and pseudorange rate of vehicles with acceleration in excess of 100 g and jerk in excess of 100 g/s, dynamics ten times more severe than specified for conventional High Dynamic GPS receivers. These results and analytic extensions to a complete system configuration establish that all range instrumentation requirements can be met. The receiver can be implemented in the 100 cu in volume required by all missiles and drones, and is ideally suited for transdigitizer or translator applications.

  4. High-Rate Receiver Design Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose an initial architectural and preliminary hardware design study for a high-rate receiver capable of decoding modulation suites specified by CCSDS 413.0-G-1...

  5. 29 CFR 1926.306 - Air receivers.

    Science.gov (United States)

    2010-07-01

    ... transportation vehicles such as steam railroad cars, electric railway cars, and automotive equipment. (2) New and... manholes therein are easily accessible. Under no circumstances shall an air receiver be buried underground...

  6. 29 CFR 1910.169 - Air receivers.

    Science.gov (United States)

    2010-07-01

    ... and equipment used on transportation vehicles such as steam railroad cars, electric railway cars, and... therein are easily accessible. Under no circumstances shall an air receiver be buried underground or...

  7. Design and implementation of the CAPS receiver

    Institute of Scientific and Technical Information of China (English)

    HU YongHui; HUA Yu; HOU Lei; WEI JingFa; WU JianFeng

    2009-01-01

    In this paper,baaed on analyses of the Chinese Area Positioning System (CAPS) satellite (GEO satellite) resources and signal properties,the signal power at the port of the receiver antenna is estimated,and the implementation projects are presented for a switching band C to band L CAPS C/A code receiver integrated with GPS receiver suite and for a CAPS dual frequency P code receiver.A microstrip receiving antenna is designed with high sensitivity and wide beam orientation,the RF front end of the C/A code and P code receivers,and a processor is designed for the navigation baseband.A single frequency CAPS C/A code receiver and a CAPS dual frequency P code receiver are built at the same time.A software process flow is provided,and research on relatively key techniques is also conducted,such as signal searching,code loop and carrier loop algorithms,a height assistant algorithm,a dual frequency difference speed measurement technique,a speed measurement technique using a single frequency source with frequency assistance,and a CAPS time correcting algorithm,according to the design frame of the receiver hardware.Research results show that the static plane positioning accuracy of the CAPS C/A code receiver is 20.5-24.6 m,height accuracy is 1.2-12.8 m,speed measurement accuracy is 0.13-0.3 m/s,dynamic plane positioning accuracy is 24.4 m,height accuracy is 3.0 m,and speed measurement accuracy is 0.24 m/s.In the case of C/A code,the timing accuracy is 200 ha,and it is also shown that the positioning accuracy of the CAPS precise code receiver (1σ) is 5 m from south to north,and 0.8 m from east to west.Finally,research on positioning accuracy is also conducted.

  8. A handbook for solar central receiver design

    Energy Technology Data Exchange (ETDEWEB)

    Falcone, P.K.

    1986-12-01

    This Handbook describes central receiver technology for solar thermal power plants. It contains a description and assessment of the major components in a central receiver system configured for utility scale production of electricity using Rankine-cycle steam turbines. It also describes procedures to size and optimize a plant and discussed examples from recent system analyses. Information concerning site selection criteria, cost estimation, construction, and operation and maintenance is also included, which should enable readers to perform design analyses for specific applications.

  9. Flexible receiver adapter formal design review

    Energy Technology Data Exchange (ETDEWEB)

    Krieg, S.A.

    1995-06-13

    This memo summarizes the results of the Formal (90%) Design Review process and meetings held to evaluate the design of the Flexible Receiver Adapters, support platforms, and associated equipment. The equipment is part of the Flexible Receiver System used to remove, transport, and store long length contaminated equipment and components from both the double and single-shell underground storage tanks at the 200 area tank farms.

  10. Anatomy of a digital coherent receiver

    DEFF Research Database (Denmark)

    Borkowski, Robert; Zibar, Darko; Tafur Monroy, Idelfonso

    2014-01-01

    Digital coherent receivers have gained significant attention in the last decade. The reason for this is that coherent detection, along with digital signal processing (DSP) allows for substantial increase of the channel capacity by employing advanced detection techniques. In this paper, we first......, orthonormaliation, chromatic dispersion compensation/nonlinear compensation, resampling a nd timing recovery, polarization demultiplexing and equalization, frequency and phase recovery, digital demodulation. We also describe novel subsystems of a digital coherent receiver: modulation format recognition...

  11. Evaluation of an Intervention to Reduce Playground Hazards in Atlanta Child-Care Centers.

    Science.gov (United States)

    Sacks, Jeffrey J.; And Others

    1992-01-01

    Revisits 58 child care centers in Atlanta (Georgia) that had received interventions alerting directors to playground safety hazards. Comparison with 71 control centers randomly selected found averages of 9.4 hazards at intervention center playgrounds and 8.0 hazards at control centers. These results indicate the ineffectiveness of the…

  12. Inversion of receiver function by wavelet transformation

    Institute of Scientific and Technical Information of China (English)

    吴庆举; 田小波; 张乃铃; 李桂银; 曾融生

    2003-01-01

    A new method for receiver function inversion by wavelet transformation is presented in this paper. Receiver func-tion is expanded to different scales with different resolution by wavelet transformation. After an initial model be-ing taken, a generalized least-squares inversion procedure is gradually carried out for receiver function from low tohigh scale, with the inversion result for low order receiver function as the initial model for high order. Aneighborhood containing the global minimum is firstly searched from low scale receiver function, and will gradu-ally focus at the global minimum by introducing high scale information of receiver function. With the gradual ad-dition of high wave-number to smooth background velocity structure, wavelet transformation can keep the inver-sion result converge to the global minimum, reduce to certain extent the dependence of inversion result on theinitial model, overcome the nonuniqueness of generalized least-squares inversion, and obtain reliable crustal andupper mantle velocity with high resolution.

  13. GPS Receiver Performance Inspection by Wavelet Transform

    Institute of Scientific and Technical Information of China (English)

    Xia Lin-yuan; Liu Jing-nan; Lu Liang-xi

    2003-01-01

    As a powerful analysis tool and the result of contemporary mathematics development, wavelet transform has shown its promising application potentials through the research in the paper. Three aspects regarding GPS receiver performance is tackled: cycle slip detection, receiver noise analysis and receiver channel bias inspection. Wavelet decomposition for double differential observation has demonstrated that this multi-level transform can reveal cycle slips as small as 0.5 cycles without any pre-adjustment processes or satellite orbit information, it can therefore be regarded as a 'geometry free' method. Based on property assumption of receiver noise, signal of noise serial is obtained at the high frequency scale in wavelet decomposition layers. This kind of noise influence on GPSb aseline result can be effectively eliminated by reconstruction process during wavelet reconstruction. Through observed data analysis, the transform has detected a kind of receiver channel bias that has not been completely removed by processing unit of GPS receiver during clock offset resetting operation. Thus the wavelet approach can be employed as a kind of system diagnosis in a generalized point of view.

  14. Efficient receiver tuning using differential evolution strategies

    Science.gov (United States)

    Wheeler, Caleb H.; Toland, Trevor G.

    2016-08-01

    Differential evolution (DE) is a powerful and computationally inexpensive optimization strategy that can be used to search an entire parameter space or to converge quickly on a solution. The Kilopixel Array Pathfinder Project (KAPPa) is a heterodyne receiver system delivering 5 GHz of instantaneous bandwidth in the tuning range of 645-695 GHz. The fully automated KAPPa receiver test system finds optimal receiver tuning using performance feedback and DE. We present an adaptation of DE for use in rapid receiver characterization. The KAPPa DE algorithm is written in Python 2.7 and is fully integrated with the KAPPa instrument control, data processing, and visualization code. KAPPa develops the technologies needed to realize heterodyne focal plane arrays containing 1000 pixels. Finding optimal receiver tuning by investigating large parameter spaces is one of many challenges facing the characterization phase of KAPPa. This is a difficult task via by-hand techniques. Characterizing or tuning in an automated fashion without need for human intervention is desirable for future large scale arrays. While many optimization strategies exist, DE is ideal for time and performance constraints because it can be set to converge to a solution rapidly with minimal computational overhead. We discuss how DE is utilized in the KAPPa system and discuss its performance and look toward the future of 1000 pixel array receivers and consider how the KAPPa DE system might be applied.

  15. Verification of ICESat-2/ATLAS Science Receiver Algorithm Onboard Databases

    Science.gov (United States)

    Carabajal, C. C.; Saba, J. L.; Leigh, H. W.; Magruder, L. A.; Urban, T. J.; Mcgarry, J.; Schutz, B. E.

    2013-12-01

    NASA's ICESat-2 mission will fly the Advanced Topographic Laser Altimetry System (ATLAS) instrument on a 3-year mission scheduled to launch in 2016. ATLAS is a single-photon detection system transmitting at 532nm with a laser repetition rate of 10 kHz, and a 6 spot pattern on the Earth's surface. A set of onboard Receiver Algorithms will perform signal processing to reduce the data rate and data volume to acceptable levels. These Algorithms distinguish surface echoes from the background noise, limit the daily data volume, and allow the instrument to telemeter only a small vertical region about the signal. For this purpose, three onboard databases are used: a Surface Reference Map (SRM), a Digital Elevation Model (DEM), and a Digital Relief Maps (DRMs). The DEM provides minimum and maximum heights that limit the signal search region of the onboard algorithms, including a margin for errors in the source databases, and onboard geolocation. Since the surface echoes will be correlated while noise will be randomly distributed, the signal location is found by histogramming the received event times and identifying the histogram bins with statistically significant counts. Once the signal location has been established, the onboard Digital Relief Maps (DRMs) will be used to determine the vertical width of the telemetry band about the signal. University of Texas-Center for Space Research (UT-CSR) is developing the ICESat-2 onboard databases, which are currently being tested using preliminary versions and equivalent representations of elevation ranges and relief more recently developed at Goddard Space Flight Center (GSFC). Global and regional elevation models have been assessed in terms of their accuracy using ICESat geodetic control, and have been used to develop equivalent representations of the onboard databases for testing against the UT-CSR databases, with special emphasis on the ice sheet regions. A series of verification checks have been implemented, including

  16. 47 CFR 15.121 - Scanning receivers and frequency converters used with scanning receivers.

    Science.gov (United States)

    2010-10-01

    ... receivers and frequency converters designed or marketed for use with scanning receivers, shall: (1) Be...; replacing a plug-in semiconductor chip; or programming a semiconductor chip using special access codes or an external device, such as a personal computer. Scanning receivers, and frequency converters designed for...

  17. Comparing Drug Use between Welfare-Receiving Arrestees and Non-Welfare-Receiving Arrestees.

    Science.gov (United States)

    Yacoubian, George S., Jr.; Peters, Ronald J., Jr.; Urbach, Blake J.; Johnson, Regina J.

    2002-01-01

    Compares drug-positive rates between welfare-receiving arrestees, non-welfare receiving arrestees living below the poverty level, and non-welfare arrestees living above the poverty level. Welfare-receiving arrestees were more likely to be female, older, less educated, and to test positive for opiates and benzodiazepines than the other subgroups.…

  18. Factors affecting willingness to receive a kidney transplant among hemodialysis patients in West China

    OpenAIRE

    Tan, Qiling; Song, Turun; Jiang, Yamei; Qiu, Yang; Liu, Jingpeng; Huang, Zhongli; Wang, Xianding; Lin, Tao

    2017-01-01

    Abstract Many factors are associated with the willingness of ESRD patients to receive a kidney transplant. No data are available for patients in China. The study aim was to describe the attitudes toward transplantation in a cohort of patients at a single dialysis center in China. A study questionnaire derived from previously published literature was completed by 239 hemodialysis outpatients. Factors associated with willingness to receive a transplant were identified by univariate and multivar...

  19. Research on Optimal Path of Data Migration among Multisupercomputer Centers

    Directory of Open Access Journals (Sweden)

    Gang Li

    2016-01-01

    Full Text Available Data collaboration between supercomputer centers requires a lot of data migration. In order to increase the efficiency of data migration, it is necessary to design optimal path of data transmission among multisupercomputer centers. Based on the situation that the target center which finished receiving data can be regarded as the new source center to migrate data to others, we present a parallel scheme for the data migration among multisupercomputer centers with different interconnection topologies using graph theory analysis and calculations. Finally, we verify that this method is effective via numeric simulation.

  20. Millimeter-wave receivers for wireless communications

    Science.gov (United States)

    Overmiller, Brock Morgan

    The modern communications environment is becoming an increasingly crowded place, resulting in rapidly increasing demands on current technology. Military and civilian operations require the ability to locate and decode all communication signals in the environment. However, developments in RADAR (RAdio Detection And Ranging) and communications technology are making it harder to effectively identify and maintain bandwidth usage for everyone. Millimeter waves--waves measured between one millimeter to one centimeter in wavelength--have only recently been explored as a new technology to replace the augment receiver architectures. These small wavelengths introduce many engineering challenges, such as: large atmospheric losses, poor sensitivity, and expensive electronic equipment. With growing developments in Microwave Photonics, low-noise RF amplifiers and high-speed modulators have demonstrated the ability to design RF communication links in the millimeter wave regime to counter such problems. However, despite these developments, toward a cost-effective, spatial division multiplexing (SDM) receiver concept has not proved capable of being implemented as part of the next generation 5G wireless network infrastructure. To this end, we present a novel receiver architecture utilizing an optically addressed phased-array millimeter wave receiver based on optical-upconversion and signal recovery. This receiver is capable of geolocation and spatial multiplexing of multiple Tunable Optically Paired Source (TOPS) communication signals in its scene. Operating at 35 GHz, the receiver up-converts the received RF onto an optical sideband, which, to our advantage, contains all of the frequency, amplitude, and phase information of the received signals. Subsequent optical processing allows routing of the sideband to a free space detector port. Photomixing a coherent optical local oscillator (LO) with the optical sideband performs heterodyne down-conversion to an Intermediate Frequency (IF

  1. Performance outlook of the SCRAP receiver

    Science.gov (United States)

    Lubkoll, Matti; von Backström, Theodor W.; Harms, Thomas M.

    2016-05-01

    A combined cycle (CC) concentrating solar power (CSP) plant provides significant potential to achieve an efficiency increase and an electricity cost reduction compared to current single-cycle plants. A CC CSP system requires a receiver technology capable of effectively transferring heat from concentrated solar irradiation to a pressurized air stream of a gas turbine. The small number of pressurized air receivers demonstrated to date have practical limitations, when operating at high temperatures and pressures. As yet, a robust, scalable and efficient system has to be developed and commercialized. A novel receiver system, the Spiky Central Receiver Air Pre-heater (SCRAP) concept has been proposed to comply with these requirements. The SCRAP system is conceived as a solution for an efficient and robust pressurized air receiver that could be implemented in CC CSP concepts or standalone solar Brayton cycles without a bottoming Rankine cycle. The presented work expands on previous publications on the thermal modeling of the receiver system. Based on the analysis of a single heat transfer element (spike), predictions for its thermal performance can be made. To this end the existing thermal model was improved by heat transfer characteristics for the jet impingement region of the spike tip as well as heat transfer models simulating the interaction with ambient. While the jet impingement cooling effect was simulated employing a commercial CFD code, the ambient heat transfer model was based on simplifying assumptions in order to employ empirical and analytical equations. The thermal efficiency of a spike under design conditions (flux 1.0 MW/m2, air outlet temperature just below 800 °C) was calculated at approximately 80 %, where convective heat losses account for 16.2 % of the absorbed radiation and radiative heat losses for a lower 2.9 %. This effect is due to peak surface temperatures occurring at the root of the spikes. It can thus be concluded that the geometric

  2. Intersatellite communications optoelectronics research at the Goddard Space Flight Center

    Science.gov (United States)

    Krainak, Michael A.

    1992-01-01

    A review is presented of current optoelectronics research and development at the NASA Goddard Space Flight Center for high-power, high-bandwidth laser transmitters; high-bandwidth, high-sensitivity optical receivers; pointing, acquisition, and tracking components; and experimental and theoretical system modeling at the NASA Goddard Space Flight Center. Program hardware and space flight opportunities are presented.

  3. Sexual function in women receiving maintenance dialysis.

    Science.gov (United States)

    Seethala, Srikanth; Hess, Rachel; Bossola, Maurizio; Unruh, Mark L; Weisbord, Steven D

    2010-01-01

    While substantial attention has been paid to the issue of sexual dysfunction in men on chronic dialysis, less is known about this problem in women with end-stage renal disease. We sought to assess sexual dysfunction in women on chronic dialysis and determine whether patients discuss this problem with their providers and receive treatment. We prospectively enrolled women receiving chronic hemodialysis or peritoneal dialysis in Pittsburgh, PA. We asked patients to complete the 19-item Female Sexual Function Index (FSFI) to assess sexual function and a 5-item survey that assessed whether patients had discussed sexual dysfunction with their providers and/or received treatment for this problem in the past. We enrolled 66 patients; 59 (89%) on hemodialysis and 7 (11%) on peritoneal dialysis. All patients completed the FSFI, of whom 53 (80%) had FSFI scores <26.55, consistent with the presence of sexual dysfunction. Of 37 patients who were married or residing with a significant other, 27 (73%) had sexual dysfunction. Among 24 participants who reported having been sexually active over the previous 4 weeks, 11 (46%) had sexual dysfunction. Only 21% of patients with sexual dysfunction had discussed this problem with their gynecologist, renal or primary provider, and 3 (6%) reported having received treatment. Sexual dysfunction is common in women on dialysis, even among patients who are married or residing with a significant other and those who are sexually active. However, few women discuss this issue with their providers or receive treatment.

  4. Receiver-Controlled Multi-Node Cooperation

    Institute of Scientific and Technical Information of China (English)

    Liang Ye; Yue Li; XueJun Sha; Esko Alasaarela

    2014-01-01

    Since wireless links in Ad hoc networks are more fragile than those in traditional wireless networks due to route flapping, multi-node cooperation plays an important role in ensuring the quality of service ( QoS) . Based on the authors’ previous work, this paper proposes a receiver-controlled multi-node cooperation routing protocol, known as AODV-RCC. In this protocol, nodes form a cooperation group based on signal power. In a cooperation group, signal power between a partner and a transmitter, as well as signal power between the partner and the receiver, must be larger than the signal power between the transmitter and the receiver. Otherwise, the transmission will not benefit from cooperation. To avoid collision or congestion, each cooperation group only contains one partner. This partner offers both data and ACK cooperative retransmission. Its retransmission time should be shorter than the internal retry time of the transmitter’ s MAC layer, because it is better for the partner to retransmit firstly, as it offers a more reliable cooperative link. In AODV-RCC, it is the receiver that chooses the partner, because the link between the partner and the receiver is the most important. According to our simulation results, AODV-RCC shortens the end-to-end delay and increases the packet delivery ratio.

  5. Schottky Heterodyne Receivers With Full Waveguide Bandwidth

    Science.gov (United States)

    Hesler, Jeffrey; Crowe, Thomas

    2011-01-01

    Compact THz receivers with broad bandwidth and low noise have been developed for the frequency range from 100 GHz to 1 THz. These receivers meet the requirements for high-resolution spectroscopic studies of planetary atmospheres (including the Earth s) from spacecraft, as well as airborne and balloon platforms. The ongoing research is significant not only for the development of Schottky mixers, but also for the creation of a receiver system, including the LO chain. The new receivers meet the goals of high sensitivity, compact size, low total power requirement, and operation across complete waveguide bands. The exceptional performance makes these receivers ideal for the broader range of scientific and commercial applications. These include the extension of sophisticated test and measurement equipment to 1 THz and the development of low-cost imaging systems for security applications and industrial process monitoring. As a particular example, a WR-1.9SHM (400-600 GHz) has been developed (see Figure 1), with state-of-the-art noise temperature ranging from 1,000-1,800 K (DSB) over the full waveguide band. Also, a Vector Network Analyzer extender has been developed (see Figure 2) for the WR1.5 waveguide band (500 750 GHz) with 100-dB dynamic range.

  6. Direct broadcast satellite-radio, receiver development

    Science.gov (United States)

    Vaisnys, A.; Bell, D.; Gevargiz, J.; Golshan, Nasser

    1993-01-01

    The status of the ongoing Direct Broadcast Satellite-Radio (DBS-R) Receiver Development Task being performed at the Jet Propulsion Laboratory, California Institute of Technology (JPL) is reported. This work is sponsored by the Voice of America/U.S. Information Agency through an agreement with NASA. The objective of this task is to develop, build, test, and demonstrate a prototype receiver that is compatible with reception of digital audio programs broadcast via satellites. The receiver is being designed to operate under a range of reception conditions, including fixed, portable, and mobile, as well as over a sufficiently wide range of bit rates to accommodate broadcasting systems with different cost/audio quality objectives. While the requirements on the receiver are complex, the eventual goal of the design effort is to make the design compatible with low cost production as a consumer product. One solution may be a basic low cost core design suitable for a majority of reception conditions, with optional enhancements for reception in especially difficult environments. Some of the receiver design parameters were established through analysis, laboratory tests, and a prototype satellite experiment accomplished in late 1991. Many of the necessary design trades will be made during the current simulation effort, while a few of the key design options will be incorporated into the prototype for evaluation during the planned satellite field trials.

  7. Dish/stirling hybrid-receiver

    Science.gov (United States)

    Mehos, Mark S.; Anselmo, Kenneth M.; Moreno, James B.; Andraka, Charles E.; Rawlinson, K. Scott; Corey, John; Bohn, Mark S.

    2002-01-01

    A hybrid high-temperature solar receiver is provided which comprises a solar heat-pipe-receiver including a front dome having a solar absorber surface for receiving concentrated solar energy, a heat pipe wick, a rear dome, a sidewall joining the front and the rear dome, and a vapor and a return liquid tube connecting to an engine, and a fossil fuel fired combustion system in radial integration with the sidewall for simultaneous operation with the solar heat pipe receiver, the combustion system comprising an air and fuel pre-mixer, an outer cooling jacket for tangentially introducing and cooling the mixture, a recuperator for preheating the mixture, a burner plenum having an inner and an outer wall, a porous cylindrical metal matrix burner firing radially inward facing a sodium vapor sink, the mixture ignited downstream of the matrix forming combustion products, an exhaust plenum, a fossil-fuel heat-input surface having an outer surface covered with a pin-fin array, the combustion products flowing through the array to give up additional heat to the receiver, and an inner surface covered with an extension of the heat-pipe wick, a pin-fin shroud sealed to the burner and exhaust plenums, an end seal, a flue-gas diversion tube and a flue-gas valve for use at off-design conditions to limit the temperature of the pre-heated air and fuel mixture, preventing pre-ignition.

  8. Direct broadcast satellite-radio, receiver development

    Science.gov (United States)

    Vaisnys, A.; Bell, D.; Gevargiz, J.; Golshan, Nasser

    The status of the ongoing Direct Broadcast Satellite-Radio (DBS-R) Receiver Development Task being performed at the Jet Propulsion Laboratory, California Institute of Technology (JPL) is reported. This work is sponsored by the Voice of America/U.S. Information Agency through an agreement with NASA. The objective of this task is to develop, build, test, and demonstrate a prototype receiver that is compatible with reception of digital audio programs broadcast via satellites. The receiver is being designed to operate under a range of reception conditions, including fixed, portable, and mobile, as well as over a sufficiently wide range of bit rates to accommodate broadcasting systems with different cost/audio quality objectives. While the requirements on the receiver are complex, the eventual goal of the design effort is to make the design compatible with low cost production as a consumer product. One solution may be a basic low cost core design suitable for a majority of reception conditions, with optional enhancements for reception in especially difficult environments. Some of the receiver design parameters were established through analysis, laboratory tests, and a prototype satellite experiment accomplished in late 1991. Many of the necessary design trades will be made during the current simulation effort, while a few of the key design options will be incorporated into the prototype for evaluation during the planned satellite field trials.

  9. Ten tips for receiving feedback effectively in clinical practice.

    Science.gov (United States)

    Algiraigri, Ali H

    2014-01-01

    Despite being recognized as a fundamental part of the educational process and emphasized for several decades in medical education, the influence of the feedback process is still suboptimal. This may not be surprising, because the focus is primarily centered on only one half of the process - the teachers. The learners are the targets of the feedback process and improvement needs to be shifted. Learners need to be empowered with the skills needed to receive and utilize feedback and compensate for less than ideal feedback delivery due to the busy clinical environment. Based on the available feedback literature and clinical experience regarding feedback, the author developed 10 tips to empower learners with the necessary skills to seek, receive, and handle feedback effectively, regardless of how it is delivered. Although, most of the tips are directed at the individual clinical trainee, this model can be utilized by clinical educators involved in learner development and serve as a framework for educational workshops or curriculum. Ten practical tips are identified that specifically address the learner's role in the feedback process. These tips not only help the learner to ask, receive, and handle the feedback, but will also ease the process for the teachers. Collectively, these tips help to overcome most, if not all, of the barriers to feedback and bridge the gaps in busy clinical practices. Feedback is a crucial element in the educational process and it is shown that we are still behind in the optimal use of it; thus, learners need to be taught how to better receive and utilize feedback. The focus in medical education needs to balance the two sides of the feedback process. It is time now to invest on the learner's development of skills that can be utilized in a busy day-to-day clinical practice.

  10. Relativistic Guiding Center Equations

    Energy Technology Data Exchange (ETDEWEB)

    White, R. B. [PPPL; Gobbin, M. [Euratom-ENEA Association

    2014-10-01

    In toroidal fusion devices it is relatively easy that electrons achieve relativistic velocities, so to simulate runaway electrons and other high energy phenomena a nonrelativistic guiding center formalism is not sufficient. Relativistic guiding center equations including flute mode time dependent field perturbations are derived. The same variables as used in a previous nonrelativistic guiding center code are adopted, so that a straightforward modifications of those equations can produce a relativistic version.

  11. Test Control Center exhibit

    Science.gov (United States)

    2000-01-01

    Have you ever wondered how the engineers at John C. Stennis Space Center in Hancock County, Miss., test fire a Space Shuttle Main Engine? The Test Control Center exhibit at StenniSphere can answer your questions by simulating the test firing of a Space Shuttle Main Engine. A recreation of one of NASA's test control centers, the exhibit explains and portrays the 'shake, rattle and roar' that happens during a real test firing.

  12. The Communication Between Designer and Design Receiver

    DEFF Research Database (Denmark)

    Dai, Zheng; Dai, Yan

    2009-01-01

    When people think about a product,the first impression always mainly influences the result.Product is the medium of communication between designer and designer receiver.Because both of them have varied different experience and background,the information would be biased during the transferring...... process.The common symbols which can be recognized by both of designer and receiver are the key tools for communication.In some case,the same symbol in one product would be leads to different receiver impression.Generally,impression includes 3 aspects:aesthetics,function, and emotion.Designer needs...... to create an attractive and accurate impression in product from these 3 aspects.For facing the dilemma of communication,some experimental approaches can help designer deal with unique and diversity situations.Solving the detail problem in each step could keep the original meaning of designer....

  13. Randomized transmit and receive ultrasound tomography

    CERN Document Server

    Clement, Gregory T

    2015-01-01

    A tomographic method is considered that forms images from sets of spatially randomized source signals and receiver sensitivities. The method is designed to allow image reconstruction for an extended number of transmitters and receivers in the presence noise and without plane wave approximation or otherwise approximation on the size or regularity of source and receiver functions. An overdetermined set of functions are formed from the Hadamard product between a Gaussian function and a uniformly distributed random number set. It is shown that this particular type of randomization tends to produce well-conditioned matrices whose pseudoinverses may be determined without implementing relaxation methods. When the inverted sets are applied to simulated first-order scattering from a Shepp-Logan phantom, successful image reconstructions are achieved for signal-to-noise ratios (SNR) as low as 1. Evaluation of the randomization approach is conducted by comparing condition numbers with other forms of signal randomization....

  14. Precision Continuum Receivers for Astrophysical Applications

    Science.gov (United States)

    Wollack, Edward J.

    2011-01-01

    Cryogenically cooled HEMT (High Electron Mobility Transistor) amplifiers find widespread use in radioastronomy receivers. In recent years, these devices have also been commonly employed in broadband receivers for precision measurements of the Cosmic Microwave Background (CMB) radiation. In this setting, the combination of ultra-low-noise and low-spectral-resolution observations reinforce the importance achieving suitable control over the device environment to achieve fundamentally limited receiver performance. The influence of the intrinsic amplifier stability at low frequencies on data quality (e.g., achievable noise and residual temporal correlations), observational and calibration strategies, as well as architectural mitigation approaches in this setting will be discussed. The implications of device level 1/f fluctuations reported in the literature on system performance will be reviewed.

  15. Performance Evaluation of an Integrated Optoelectronic Receiver

    Directory of Open Access Journals (Sweden)

    A. Vera-Marquina

    2014-02-01

    Full Text Available This work describes the optical and electrical characterization of an integrated optoelectronic receiver. The receiver is composed of a photodiode and a transimpedance amplifier, both fabricated in silicon technology using a 0.8 μm BiCMOS process. The total area occupied by the photodiode is of 10,000 μm2. In a first step, the generated photocurrent of the photodiode is measured for the wavelengths of 780 nm and 830 nm at different levels of optical power. In a second step, the responsivity and quantum efficiency parameters of the photodiode are computed. Finally, an electrical measurement including the transimpedance amplifier is achieved. A potential application for this optoelectronic receiver is on the first optical communications window.

  16. Implementation of Universal Asynchronous Receiver and Transmitter

    Directory of Open Access Journals (Sweden)

    Payata Srikanth Yadav

    2015-03-01

    Full Text Available Universal Asynchronous Receiver Transmitter (UART is the serial communication protocol that is used for data exchange between computer & peripherals. UART is a low velocity, short-distance, low-cost protocol. UART includes three modules which are received, the baud rate generator and transmitter. The UART design with Very High Description Language can be integrated into the Field Programmable Gate Array to achieve stable data transmission and to make system reliable and compact. In the result and simulation part, this project will focus on check the receive data with error free & baud rate generation at different frequencies. Before synthesizing of UART a baud rate generator is incorporated into the system. We use the frequency divider which sets itself to required frequency for the functionality at lower frequency. All modules are designed using VERILOG and implemented on Xilinx Suite development board.

  17. Multiple Antenna Cognitive Receivers and Signal Detection

    CERN Document Server

    Couillet, Romain

    2008-01-01

    A Bayesian inference learning process for cognitive receivers is provided in this paper. We focus on the particular case of signal detectionas an explanatory example to the learning framework. Under any prior state of knowledge on the communication channel, an information theoretic criterion is presented to decide on the presence of informative data in a noisy wireless MIMO communication. We detail the particular cases of knowledge, or absence of knowledge at the receiver, of the number of transmit antennas and noise power. The provided method is instrumental to provide intelligence to the receiver and gives birth to a novel Bayesian signal detector. The detector is compared to the classical power detector and provides detection performance upper bounds. Simulations corroborate the theoretical results and quantify the gain achieved using the proposed Bayesian framework.

  18. Antennas and Receivers in Radio Interferometry

    CERN Document Server

    Hunter, Todd R

    2016-01-01

    The primary antenna elements and receivers are two of the most important components in a synthesis telescope. Together they are responsible for locking onto an astronomical source in both direction and frequency, capturing its radiation, and converting it into signals suitable for digitization and correlation. The properties and performance of antennas and receivers can affect the quality of the synthesized images in a number of fundamental ways. In this lecture, their most relevant design and performance parameters are reviewed, with emphasis on the current ALMA and VLA systems. We discuss in detail the shape of the primary beam and the components of aperture efficiency, and we present the basics of holography, pointing, and servo control. On receivers, we outline the use of amplifiers and mixers both in the cryogenic front-end and in the room temperature back-end signal path. The essential properties of precision local oscillators (LOs), phase lock loops (PLLs), and LO modulation techniques are also describ...

  19. Olympus receiver evaluation and phase noise measurements

    Science.gov (United States)

    Campbell, Richard L.; Wang, Huailiang; Sweeney, Dennis

    1990-01-01

    A set of measurements performed by the Michigan Tech Sensing and Signal Processing Group on the analog receiver built by the Virginia Polytechnic Institute (VPI) and the Jet Propulsion Laboratory (JPL) for propagation measurements using the Olympus Satellite is described. Measurements of local oscillator (LO) phase noise were performed for all of the LOs supplied by JPL. In order to obtain the most useful set of measurements, LO phase noise measurements were made using the complete VPI receiver front end. This set of measurements demonstrates the performance of the receiver from the Radio Frequency (RF) input through the high Intermediate Frequency (IF) output. Three different measurements were made: LO phase noise with DC on the voltage controlled crystal oscillator (VCXO) port; LO phase noise with the 11.381 GHz LO locked to the reference signal generator; and a reference measurement with the JPL LOs out of the system.

  20. Great Lakes Science Center

    Data.gov (United States)

    Federal Laboratory Consortium — Since 1927, Great Lakes Science Center (GLSC) research has provided critical information for the sound management of Great Lakes fish populations and other important...

  1. Electron Microscopy Center (EMC)

    Data.gov (United States)

    Federal Laboratory Consortium — The Electron Microscopy Center (EMC) at Argonne National Laboratory develops and maintains unique capabilities for electron beam characterization and applies those...

  2. Center for Deployment Psychology

    Data.gov (United States)

    Federal Laboratory Consortium — The Center for Deployment Psychology was developed to promote the education of psychologists and other behavioral health specialists about issues pertaining to the...

  3. Test Control Center (TCC)

    Data.gov (United States)

    Federal Laboratory Consortium — The Test Control Center (TCC) provides a consolidated facility for planning, coordinating, controlling, monitoring, and analyzing distributed test events. ,The TCC...

  4. Environmental Modeling Center

    Data.gov (United States)

    Federal Laboratory Consortium — The Environmental Modeling Center provides the computational tools to perform geostatistical analysis, to model ground water and atmospheric releases for comparison...

  5. Audio Visual Center

    Data.gov (United States)

    Federal Laboratory Consortium — The Audiovisual Services Center provides still photographic documentation with laboratory support, video documentation, video editing, video duplication, photo/video...

  6. Small Business Development Center

    Data.gov (United States)

    Small Business Administration — Small Business Development Centers (SBDCs) provide assistance to small businesses and aspiring entrepreneurs throughout the United States and its territories. SBDCs...

  7. Data Center at NICT

    Science.gov (United States)

    Ichikawa, Ryuichi; Sekido, Mamoru

    2013-01-01

    The Data Center at the National Institute of Information and Communications Technology (NICT) archives and releases the databases and analysis results processed at the Correlator and the Analysis Center at NICT. Regular VLBI sessions of the Key Stone Project VLBI Network were the primary objective of the Data Center. These regular sessions continued until the end of November 2001. In addition to the Key Stone Project VLBI sessions, NICT has been conducting geodetic VLBI sessions for various purposes, and these data are also archived and released by the Data Center.

  8. Advanced Simulation Center

    Data.gov (United States)

    Federal Laboratory Consortium — The Advanced Simulation Center consists of 10 individual facilities which provide missile and submunition hardware-in-the-loop simulation capabilities. The following...

  9. Surgery center joint ventures.

    Science.gov (United States)

    Zasa, R J

    1999-01-01

    Surgery centers have been accepted as a cost effective, patient friendly vehicle for delivery of quality ambulatory care. Hospitals and physician groups also have made them the vehicles for coming together. Surgery centers allow hospitals and physicians to align incentives and share benefits. It is one of the few types of health care businesses physicians can own without anti-fraud and abuse violation. As a result, many surgery center ventures are now jointly owned by hospitals and physician groups. This article outlines common structures that have been used successfully to allow both to own and govern surgery centers.

  10. Chemical Security Analysis Center

    Data.gov (United States)

    Federal Laboratory Consortium — In 2006, by Presidential Directive, DHS established the Chemical Security Analysis Center (CSAC) to identify and assess chemical threats and vulnerabilities in the...

  11. Airline Operation Center Workstation

    Data.gov (United States)

    Department of Transportation — The Airline Operation Center Workstation (AOC Workstation) represents equipment available to users of the National Airspace system, outside of the FAA, that enables...

  12. The new indicators of accounts receivable excellence.

    Science.gov (United States)

    Lampi, G L

    1996-01-01

    Calculation of AR days will continue to be a valuable internal measurement tool of accounts receivable excellence. As healthcare organizations move toward managed care through a mix of reimbursement systems--many with conflicting incentives--the director of patient accounting must approach each system separately and ensure that the hospital receives all of the reimbursement to which it is entitled. The director of patient accounting must understand the industry and recognize that healthcare reimbursement will almost certainly continue to become more complex rather than simpler. Creativity will be a necessity, and good luck will be an advantage.

  13. On Satellite Multicast to Heterogeneous Receivers

    Science.gov (United States)

    2001-01-01

    combined into one bulk file. Let the multicast source use Reed-Solomon erasure ( RSE ) coding (e.g. [Mac97]) and let the bulk file be encoded into W ≥ 1... RSE -based FEC blocks. Each FEC block consists of h data packets and c parity packets – all of the same length. We assume a multicast tree that has a... RSE -based FEC block, a receiver must receive at least h distinct packets, either data or parity, from the same FEC block. To allow a systematic way

  14. Building and Testing a Portable VLF Receiver

    Science.gov (United States)

    McLaughlin, Robert; Krause, L.

    2014-01-01

    Unwanted emissions or signal noise is a major problem for VLF radio receivers. These can occur from man made sources such as power line hum, which can be prevalent for many harmonics after the fundamental 50 or 60 Hz AC source or from VLF radio transmissions such as LORAN, used for navigation and communications. Natural emissions can also be detrimental to the quality of recordings as some of the more interesting natural emissions such as whistlers or auroral chorus may be drowned out by the more common sferic emissions. VLF receivers must selectively filter out unwanted emissions and amplify the filtered signal to a record-able level without degrading the quality.

  15. Avalanche Photodiode Arrays for Optical Communications Receivers

    Science.gov (United States)

    Srinivasan, M.; Vilnrotter, V.

    2001-01-01

    An avalanche photodiode (APD) array for ground-based optical communications receivers is investigated for the reception of optical signals through the turbulent atmosphere. Kolmogorov phase screen simulations are used to generate realistic spatial distributions of the received optical field. It is shown that use of an APD array for pulse-position modulation detection can improve performance by up to 4 dB over single APD detection in the presence of turbulence, but that photon-counting detector arrays yield even greater gains.

  16. Financing with Receivables: Factoring, Securitization and Collateral

    Directory of Open Access Journals (Sweden)

    Ioana Benea

    2013-11-01

    Full Text Available Short term financing is vital for the financial survival of any company, because very often they are facing deficits of cash during their activity. Therefore a company has to identify the optimal solutions in order to cover those (temporary deficits. A good solution to this problem is the financing with receivables using factoring, securitization and collateral. In this paper we try to analyze how this types of financing works and which are their advantages and costs. Also, we developed a reasoning pattern in order to evaluate the best receivables financing alternative for the Romanian companies.

  17. Superconducting Submm Integrated Receiver for TELIS

    NARCIS (Netherlands)

    Koshelets, V. P.; Ermakov, A. B.; Filippenko, L. V.; Koryukin, O. V.; Khudchenko, A. V.; Sobolev, A. S.; Torgashin, M. Yu; Yagoubov, P. A.; Hoogeveen, R. W. M.; Vreeling, W. J.; Wild, W.; Pylypenko, O. M.

    2006-01-01

    In this report we present design and first experimental results for development of the submm superconducting integrated receiver spectrometer for Terahertz Limb Sounder (TELIS). TELIS is a collaborative European project to build up a three-channel heterodyne balloon-based spectrometer for measuring

  18. A 24GHz Radar Receiver in CMOS

    NARCIS (Netherlands)

    Kwok, K.C.

    2015-01-01

    This thesis investigates the system design and circuit implementation of a 24GHz-band short-range radar receiver in CMOS technology. The propagation and penetration properties of EM wave offer the possibility of non-contact based remote sensing and through-the-wall imaging of distance stationary or

  19. Reasons Parents Exempt Children from Receiving Immunizations

    Science.gov (United States)

    Luthy, Karlen E.; Beckstrand, Renea L.; Callister, Lynn C.; Cahoon, Spencer

    2012-01-01

    School nurses are on the front lines of educational efforts to promote childhood vaccinations. However, some parents still choose to exempt their children from receiving vaccinations for personal reasons. Studying the beliefs of parents who exempt vaccinations allows health care workers, including school nurses, to better understand parental…

  20. CAS expert receives Tribology Gold Medal

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    Prof. XUE Qunji, a senior expert in tribology from the CAS Lanzhou Institute of Chemical Physics (L1CP) and member of the Chinese Academy of Engineering, received the Tribology Gold Medalfor 2011 on February 27, 2012 in Beijing. As one of the world's most outstanding and influential tribologists in the last forty years, Prof.

  1. Receiving Assistance and Local Food System Participation

    Directory of Open Access Journals (Sweden)

    Rebecca L. Som Castellano

    2017-02-01

    Full Text Available A body of literature has noted that local food systems (LFSs may not involve active participation by individuals with lower incomes. This is, in part, a function of racial and class hegemony, as well as physical and financial accessibility of LFSs. LFS institutions, such as farmers’ markets, have been working to facilitate receipt of food assistance programs, such as the Supplemental Nutrition Assistance Program (SNAP. Charitable assistance programs, such as food banks, have also been actively working to engage in LFSs, for example, by making local foods available. However, little research has explored the role that receiving public or charitable assistance can play in influencing LFS participation. In this article, I utilize quantitative and qualitative data collected from across the state of Ohio to examine the relationship between receiving assistance and LFS participation for women, who remain predominately responsible for food provisioning in the U.S., including among those who participate in LFSs. Quantitative results suggest that receiving assistance can increase participation in LFSs. Qualitative data provides more nuanced information about the importance of food assistance for women who want to participate in LFSs, and suggest that it is essential that food cooperatives and farmers’ markets are equipped to receive food assistance programs, such as SNAP, in order for women with lower incomes to participate in LFSs.

  2. Why Receiving Feedback Collides with Self Determination

    Science.gov (United States)

    ten Cate, Olle Th. J.

    2013-01-01

    Providing feedback to trainees in clinical settings is considered important for development and acquisition of skill. Despite recommendations how to provide feedback that have appeared in the literature, research shows that its effectiveness is often disappointing. To understand why receiving feedback is more difficult than it appears, this paper…

  3. A 24GHz Radar Receiver in CMOS

    NARCIS (Netherlands)

    Kwok, K.C.

    2015-01-01

    This thesis investigates the system design and circuit implementation of a 24GHz-band short-range radar receiver in CMOS technology. The propagation and penetration properties of EM wave offer the possibility of non-contact based remote sensing and through-the-wall imaging of distance stationary or

  4. Howard Feiertag receives hospitality industry award

    OpenAIRE

    Ho, Sookhan

    2004-01-01

    Howard Feiertag, of Blacksburg, an instructor in hospitality and tourism management at Virginia Tech's Pamplin College of Business, received the inaugural Excellence in Sales and Marketing Strategy Award at the Hospitality Sales and Marketing Association/New York University Strategy Conference in New York recently.

  5. Compressed Sensing-Based Direct Conversion Receiver

    DEFF Research Database (Denmark)

    Pierzchlewski, Jacek; Arildsen, Thomas; Larsen, Torben

    2012-01-01

    Due to the continuously increasing computational power of modern data receivers it is possible to move more and more processing from the analog to the digital domain. This paper presents a compressed sensing approach to relaxing the analog filtering requirements prior to the ADCs in a direct...

  6. Richard W. Ziolkowski Receives Honorary Doctorate

    DEFF Research Database (Denmark)

    Breinbjerg, Olav

    2012-01-01

    At the annual Commemoration of the Technical University of Denmark (DTU) on April 27, 2012, Prof. Richard W. Ziolkowski, University of Arizona (UoA), received DTU's highest academic degree, the Honorary Doctor degree: Doctor Technices Honoris Causa (Figure 1). Prof. Ziolkowski has been a close...

  7. Reasons Parents Exempt Children from Receiving Immunizations

    Science.gov (United States)

    Luthy, Karlen E.; Beckstrand, Renea L.; Callister, Lynn C.; Cahoon, Spencer

    2012-01-01

    School nurses are on the front lines of educational efforts to promote childhood vaccinations. However, some parents still choose to exempt their children from receiving vaccinations for personal reasons. Studying the beliefs of parents who exempt vaccinations allows health care workers, including school nurses, to better understand parental…

  8. Radiometric Receiver for Passive Microwave Imaging System

    Directory of Open Access Journals (Sweden)

    Ubaichin Anton

    2016-01-01

    Full Text Available The paper describes a new method to develop a zero-type W-band radiometric receiver. The block diagram and operating algorithm of the digital control system are presented. The main advantages of the zero method in passive radio physical investigations in comparison with classical engineering solutions are shown.

  9. 7 CFR 29.42 - Receiving station.

    Science.gov (United States)

    2010-01-01

    ... Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... INSPECTION Regulations Definitions § 29.42 Receiving station. Points at which producer tobacco is offered for marketing (other than sale at auction on a designated market), including tobacco auction warehouses,...

  10. Howard Feiertag receives hospitality industry award

    OpenAIRE

    Ho, Sookhan

    2004-01-01

    Howard Feiertag, of Blacksburg, an instructor in hospitality and tourism management at Virginia Tech's Pamplin College of Business, received the inaugural Excellence in Sales and Marketing Strategy Award at the Hospitality Sales and Marketing Association/New York University Strategy Conference in New York recently.

  11. Carbon Monoxide Information Center

    Medline Plus

    Full Text Available ... main content Languages 简体中文 English Bahasa Indonesia 한국어 Español ภาษาไทย Tiếng Việt Text Size: Decrease Font Increase ... Monoxide Information Center Carbon Monoxide Information Center En Español The Invisible Killer Carbon monoxide, also known as ...

  12. Assessing the Assessment Center.

    Science.gov (United States)

    LaRue, James

    1989-01-01

    Describes the historical use of assessment centers as staff development and promotional tools and their current use in personnel selection. The elements that constitute a true assessment center are outlined, and a discussion of the advantages and disadvantages for employers and applicants focuses on positions in library administration. (10…

  13. Dimensioning large call centers

    NARCIS (Netherlands)

    S.C. Borst (Sem); A. Mandelbaum; M.I. Reiman

    2000-01-01

    textabstractWe develop a framework for asymptotic optimization of a queueing system. The motivation is the staffing problem of call centers with 100's of agents (or more). Such a call center is modeled as an M/M/N queue, where the number of agents~$N$ is large. Within our framework, we determine the

  14. Information Centers at NAL.

    Science.gov (United States)

    Frank, Robyn C.

    1989-01-01

    Descriptions of the 12 specialized information centers of the National Agricultural Library (NAL) include subject coverage, information services provided, information technologies used, and staffing. The development of the Rural Information Center, a joint venture between the Extension Service and NAL to provide information services to local…

  15. Handbook for Learning Centers.

    Science.gov (United States)

    Norwalk Board of Education, CT.

    The handbook for learning centers contains guidelines, forms, and supplementary information to be used with all children identified as having a learning disability, mild retardation, or sensory deprivation in the Norwalk, Connecticut public schools. It is stressed that the learning center should provide supportive services for at least 35 minutes…

  16. Funding Opportunity: Genomic Data Centers

    Science.gov (United States)

    Funding Opportunity CCG, Funding Opportunity Center for Cancer Genomics, CCG, Center for Cancer Genomics, CCG RFA, Center for cancer genomics rfa, genomic data analysis network, genomic data analysis network centers,

  17. PTSD: National Center for PTSD

    Medline Plus

    Full Text Available ... Locator Hospitals and Clinics Vet Centers Regional Benefits Offices Regional Loan Centers Cemetery Locations Search Enter your ... Clinic Locations Hospitals & Clinics Vet Centers Regional Benefits Offices Regional Loan Centers Cemetery Locations Contact Us FAQs ...

  18. Relative Lyapunov Center Bifurcations

    DEFF Research Database (Denmark)

    Wulff, Claudia; Schilder, Frank

    2014-01-01

    Relative equilibria (REs) and relative periodic orbits (RPOs) are ubiquitous in symmetric Hamiltonian systems and occur, for example, in celestial mechanics, molecular dynamics, and rigid body motion. REs are equilibria, and RPOs are periodic orbits of the symmetry reduced system. Relative Lyapunov...... center bifurcations are bifurcations of RPOs from REs corresponding to Lyapunov center bifurcations of the symmetry reduced dynamics. In this paper we first prove a relative Lyapunov center theorem by combining recent results on the persistence of RPOs in Hamiltonian systems with a symmetric Lyapunov...... center theorem of Montaldi, Roberts, and Stewart. We then develop numerical methods for the detection of relative Lyapunov center bifurcations along branches of RPOs and for their computation. We apply our methods to Lagrangian REs of the N-body problem....

  19. Carbon Characterization Laboratory Readiness to Receive Irradiated Graphite Samples

    Energy Technology Data Exchange (ETDEWEB)

    Karen A. Moore

    2011-05-01

    The Carbon Characterization Laboratory (CCL) is located in Labs C19 and C20 of the Idaho National Laboratory Research Center. The CCL was established under the Next Generation Nuclear Plant Project to support graphite and ceramic composite research and development activities. The research conducted in this laboratory will support the Advanced Graphite Creep experiments—a major series of material irradiation experiments within the Next Generation Nuclear Plant Graphite program. The CCL is designed to characterize and test low activated irradiated materials such as high purity graphite, carbon-carbon composites, silicon-carbide composite, and ceramic materials. The laboratory is fully capable of characterizing material properties for both irradiated and nonirradiated materials. Major infrastructural modifications were undertaken to support this new radiological facility at Idaho National Laboratory. Facility modifications are complete, equipment has been installed, radiological controls and operating procedures have been established and work management documents have been created to place the CCL in readiness to receive irradiated graphite samples.

  20. Vulcan: A deep-towed CSEM receiver

    Science.gov (United States)

    Constable, Steven; Kannberg, Peter K.; Weitemeyer, Karen

    2016-03-01

    We have developed a three-axis electric field receiver designed to be towed behind a marine electromagnetic transmitter for the purpose of mapping the electrical resistivity in the upper 1000 m of seafloor geology. By careful adjustment of buoyancy and the use of real-time monitoring of depth and altitude, we are able to deep-tow multiple receivers on arrays up to 1200 m long within 50 m of the seafloor, thereby obtaining good coupling to geology. The rigid body of the receiver is designed to reduce noise associated with lateral motion of flexible antennas during towing, and allows the measurement of the vertical electric field component, which modeling shows to be particularly sensitive to near-seafloor resistivity variations. The positions and orientations of the receivers are continuously measured, and realistic estimates of positioning errors can be used to build an error model for the data. During a test in the San Diego Trough, offshore California, inversions of the data were able to fit amplitude and phase of horizontal electric fields at three frequencies on three receivers to about 1% in amplitude and 1° in phase and vertical fields to about 5% in amplitude and 5° in phase. The geological target of the tests was a known cold seep and methane vent in 1000 m water depth, which inversions show to be associated with a 1 km wide resistor at a depth between 50 and 150 m below seafloor. Given the high resistivity (30 Ωm) and position within the gas hydrate stability field, we interpret this to be massive methane hydrate.

  1. Social effects of migration in receiving countries.

    Science.gov (United States)

    Ohndorf, W

    1989-06-01

    This paper examines the impact of post-1945 migration into Western, Middle, and Northern Europe from Southern Europe, Turkey, and Northern Africa, and migration to the traditional immigration countries by Asian and Latin American immigrants, on the social structures of receiving countries. Between 1955 and 1974, 1) traditional migration to the US and Australia became less important for European countries while traditional receiving countries accepted many immigrants from developing countries; and 2) rapid economic revival in Western and Northern Europe caused a considerable labor shortage which was filled by migrant workers especially from Southern Europe, Turkey, and Northern Africa, who stayed only until they reached their economic goals. Since 1974, job vacancies have declined and unemployment has soared. This employment crisis caused some migrants 1) to return to their countries of origin, 2) to bring the rest of their families to the receiving country, or 3) to lengthen their stay considerably. The number of refugees has also significantly increased since the mid-970s, as has the number of illegal migrants. After the mid-1970s, Europe began to experience integration problems. The different aspects of the impact of migration on social structures include 1) improvement of the housing situation for foreigners, 2) teaching migrants the language of the receiving country, 3) solving the unemployment problem of unskilled migrants, 4) improvement of educational and vocational qualifications of 2nd generation migrants, 5) development of programs to help unemployed wives of migrants to learn the language and meet indigenous women, 6) encouraging migrants to maintain their cultural identity and assisting them with reintegration if they return to their original country, 7) coping with the problems of refugees, and 8) solving the problems of illegal migration. Almost all receiving countries now severely restrict further immigration. [Those policies should result in

  2. Early Intervention for Children with Hearing Loss: Information Parents Receive about Supporting Children's Language

    Science.gov (United States)

    Decker, Kalli B.; Vallotton, Claire D.

    2016-01-01

    Family-centered early intervention for children with hearing loss is intended to strengthen families' interactions with their children to support children's language development, and should include providing parents with information they can use as part of their everyday routines. However, little is known about the information received by families…

  3. Early Intervention for Children with Hearing Loss: Information Parents Receive about Supporting Children's Language

    Science.gov (United States)

    Decker, Kalli B.; Vallotton, Claire D.

    2016-01-01

    Family-centered early intervention for children with hearing loss is intended to strengthen families' interactions with their children to support children's language development, and should include providing parents with information they can use as part of their everyday routines. However, little is known about the information received by families…

  4. Spillage and flux density on a receiver aperture lip. [of solar thermal collector

    Science.gov (United States)

    Jaffe, L. D.

    1985-01-01

    In a dish-type point-focusing solar thermal collector, the spillage and the flux density on the receiver aperture lip are related in a very simple way, if the aperture is circular and centered on the optical axis. Specifically, the flux density on the lip is equal to the spillage times the peak flux density in the plane of the lip.

  5. Energy efficient data centers

    Energy Technology Data Exchange (ETDEWEB)

    Tschudi, William; Xu, Tengfang; Sartor, Dale; Koomey, Jon; Nordman, Bruce; Sezgen, Osman

    2004-03-30

    Data Center facilities, prevalent in many industries and institutions are essential to California's economy. Energy intensive data centers are crucial to California's industries, and many other institutions (such as universities) in the state, and they play an important role in the constantly evolving communications industry. To better understand the impact of the energy requirements and energy efficiency improvement potential in these facilities, the California Energy Commission's PIER Industrial Program initiated this project with two primary focus areas: First, to characterize current data center electricity use; and secondly, to develop a research ''roadmap'' defining and prioritizing possible future public interest research and deployment efforts that would improve energy efficiency. Although there are many opinions concerning the energy intensity of data centers and the aggregate effect on California's electrical power systems, there is very little publicly available information. Through this project, actual energy consumption at its end use was measured in a number of data centers. This benchmark data was documented in case study reports, along with site-specific energy efficiency recommendations. Additionally, other data center energy benchmarks were obtained through synergistic projects, prior PG&E studies, and industry contacts. In total, energy benchmarks for sixteen data centers were obtained. For this project, a broad definition of ''data center'' was adopted which included internet hosting, corporate, institutional, governmental, educational and other miscellaneous data centers. Typically these facilities require specialized infrastructure to provide high quality power and cooling for IT equipment. All of these data center types were considered in the development of an estimate of the total power consumption in California. Finally, a research ''roadmap'' was developed

  6. Stennis Space Center observes Disability Awareness Day

    Science.gov (United States)

    2009-01-01

    Members of STARC, a non-profit organization in Slidell, La., that seeks to help people with disabilities lead meaningful, productive lives, pose with their appreciation awards during Disability Awareness Day at Stennis Space Center on Oct. 15. The group members received appreciation awards for their dedicated service to the rocket engine testing facility. Disability Awareness Day was hosted by the Stennis Diversity Council and included guest speakers from several area agencies.

  7. Stennis Space Center observes Disability Awareness Day

    Science.gov (United States)

    2009-01-01

    Members of STARC, a non-profit organization in Slidell, La., that seeks to help people with disabilities lead meaningful, productive lives, pose with their appreciation awards during Disability Awareness Day at Stennis Space Center on Oct. 15. The group members received appreciation awards for their dedicated service to the rocket engine testing facility. Disability Awareness Day was hosted by the Stennis Diversity Council and included guest speakers from several area agencies.

  8. Automatic tuning of flexible interventional RF receiver coils.

    Science.gov (United States)

    Venook, Ross D; Hargreaves, Brian A; Gold, Garry E; Conolly, Steven M; Scott, Greig C

    2005-10-01

    Microcontroller-based circuitry was built and tested for automatically tuning flexible RF receiver coils at the touch of a button. This circuitry is robust to 10% changes in probe center frequency, is in line with the scanner, and requires less than 1 s to tune a simple probe. Images were acquired using this circuitry with a varactor-tunable 1-inch flexible probe in a phantom and in an in vitro porcine knee model. The phantom experiments support the use of automatic tuning by demonstrating 30% signal-to-noise ratio (SNR) losses for 5% changes in coil center frequency, in agreement with theoretical calculations. Comparisons between patellofemoral cartilage images obtained using a 3-inch surface coil and the surgically-implanted 1-inch flexible coil reveal a worst-case local SNR advantage of a factor of 4 for the smaller coil. This work confirms that surgically implanted coils can greatly improve resolution in small-field-of-view (FOV) applications, and demonstrates the importance and feasibility of automatically tuning such probes.

  9. The performance analysis of linux networking - packet receiving

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Wenji; Crawford, Matt; Bowden, Mark; /Fermilab

    2006-11-01

    The computing models for High-Energy Physics experiments are becoming ever more globally distributed and grid-based, both for technical reasons (e.g., to place computational and data resources near each other and the demand) and for strategic reasons (e.g., to leverage equipment investments). To support such computing models, the network and end systems, computing and storage, face unprecedented challenges. One of the biggest challenges is to transfer scientific data sets--now in the multi-petabyte (10{sup 15} bytes) range and expected to grow to exabytes within a decade--reliably and efficiently among facilities and computation centers scattered around the world. Both the network and end systems should be able to provide the capabilities to support high bandwidth, sustained, end-to-end data transmission. Recent trends in technology are showing that although the raw transmission speeds used in networks are increasing rapidly, the rate of advancement of microprocessor technology has slowed down. Therefore, network protocol-processing overheads have risen sharply in comparison with the time spent in packet transmission, resulting in degraded throughput for networked applications. More and more, it is the network end system, instead of the network, that is responsible for degraded performance of network applications. In this paper, the Linux system's packet receive process is studied from NIC to application. We develop a mathematical model to characterize the Linux packet receiving process. Key factors that affect Linux systems network performance are analyzed.

  10. A receiver function study across the Dead Sea Basin (DSB)

    Science.gov (United States)

    Mohsen, A.; Asch, G.; Hofstetter, R.; Kind, R.; Weber, M.

    2008-12-01

    Beginning in September 2006, a temporary network of 30 broadband and 45 short-period seismic stations has been set up on both sides of the Dead Sea Basin (DSB). During one and a half year of successful operation, data were continuously recorded in the field at 100 Hz and 200 Hz sample frequency for the broadband and short-period seismic stations, respectively. The raw data were converted to miniseed format and archived as full seed volume in the GEOFON data center of the GFZ. In the present work, the Receiver Function Method has been applied to the three component passive source data to investigate seismic discontinuities from the crust down to the upper mantle. Unusual negative phases at about 1s delay time have been observed at several stations in the Dead Sea region on the top of the assumed salt diapir. First preliminary receiver function analysis reveals a crustal thickness of about 30 -35 km in the investigated area and possibly low-velocity layer beneath the Moho. It also shows a basin which is possibly filled with salt about 10 km thick beneath the Lisan peninsula (Dead Sea).

  11. Cold Start Strategy of the CubeSat GPS Receiver

    Directory of Open Access Journals (Sweden)

    KOVAR, P.

    2014-05-01

    Full Text Available The cold start of the LEO satellite GPS receiver is complicated due to a large Doppler frequency shift, Doppler frequency rate of the navigation signals and a rapid change of the satellite visibility. The cold start time can be shortened by a proper strategy of a selection of the satellites to be searched for. The cold start simulator was developed and used for optimization of the sequence of the satellites search, for development and testing of an advanced satellite selection algorithm that utilizes information on the satellites already detected and for optimization of a frequency search range. The best performance was achieved by using an advanced selection strategy. The strategy is based on the selection of the satellites nearest to the detected satellite, using the average angle between the Earth center (apex and the satellites. Furthermore, the simulation shows that it is not practical to investigate all frequencies within the range of the maximum possible Doppler frequency shift of the carrier wave of the navigation signal, but investigate approximately +/- 35 kHz range and, if not successful, switch to the next satellite. The simulations proved that a simple GPS receiver with the sequential search algorithms can operate in the LEO orbit.

  12. CERN Press Office receives award from Euroscience

    CERN Multimedia

    2009-01-01

    The CERN Communication group has received an award for its efforts in communicating the LHC first beam to the media and the public. James Gillies, head of the Communication group was presented the AlphaGalileo Research Public Relations Award on Wednesday, 14 October during the Euroscience Media Award Ceremony in Hannover. "It’s great to receive this recognition," said Gillies. "Of course, we had great material to work with: the LHC is a fantastic story and one that is going to get even better. Angels, Demons and black holes also had their roles to play, but behind the media interest there’s been a lot of hard work by my team. This is for them." The CERN Communication group also works with communication professionals in all the CERN Member States and major physics labs around the world through the European Particle Physics Communication Network, and the InterAction collaboration. "Without them," says Gillies, &am...

  13. Grooms receives 2011 Donald L. Turcotte Award

    Science.gov (United States)

    2012-02-01

    Ian Grooms has been awarded the AGU Donald L. Turcotte Award, given annually to recent Ph.D. recipients for outstanding dissertation research that contributes directly to the field of nonlinear geophysics. Grooms's thesis is entitled “Asymptotic and numerical methods for rapidly rotating buoyant flow.” He presented an invited talk and was formally presented with the award at the 2011 AGU Fall Meeting, held 5-9 December in San Francisco, Calif. Grooms received his B.S. in mathematics from the College of William and Mary, Williamsburg, Va., in 2005. He received a Ph.D. in applied mathematics in 2011 under the supervision of Keith Julien at the University of Colorado at Boulder. His research interests include asymptotic and numerical methods for multiscale problems in geophysical fluid dynamics.

  14. Screen-printed flexible MRI receive coils.

    Science.gov (United States)

    Corea, Joseph R; Flynn, Anita M; Lechêne, Balthazar; Scott, Greig; Reed, Galen D; Shin, Peter J; Lustig, Michael; Arias, Ana C

    2016-03-10

    Magnetic resonance imaging is an inherently signal-to-noise-starved technique that limits the spatial resolution, diagnostic image quality and results in typically long acquisition times that are prone to motion artefacts. This limitation is exacerbated when receive coils have poor fit due to lack of flexibility or need for padding for patient comfort. Here, we report a new approach that uses printing for fabricating receive coils. Our approach enables highly flexible, extremely lightweight conforming devices. We show that these devices exhibit similar to higher signal-to-noise ratio than conventional ones, in clinical scenarios when coils could be displaced more than 18 mm away from the body. In addition, we provide detailed material properties and components performance analysis. Prototype arrays are incorporated within infant blankets for in vivo studies. This work presents the first fully functional, printed coils for 1.5- and 3-T clinical scanners.

  15. Fused silica windows for solar receiver applications

    Science.gov (United States)

    Hertel, Johannes; Uhlig, Ralf; Söhn, Matthias; Schenk, Christian; Helsch, Gundula; Bornhöft, Hansjörg

    2016-05-01

    A comprehensive study of optical and mechanical properties of quartz glass (fused silica) with regard to application in high temperature solar receivers is presented. The dependence of rupture strength on different surface conditions as well as high temperature is analyzed, focussing particularly on damage by devitrification and sandblasting. The influence of typical types of contamination in combination with thermal cycling on the optical properties of fused silica is determined. Cleaning methods are compared regarding effectiveness on contamination-induced degradation for samples with and without antireflective coating. The FEM-aided design of different types of receiver windows and their support structure is presented. A large-scale production process has been developed for producing fused silica dome shaped windows (pressurized window) up to a diameter of 816 mm. Prototypes were successfully pressure-tested in a test bench and certified according to the European Pressure Vessel Directive.

  16. Perception of older adults receiving palliative care

    Directory of Open Access Journals (Sweden)

    Fernanda Laporti Seredynskyj

    2014-06-01

    Full Text Available The present study aimed at understanding the perception of older adults who are receiving palliative oncological care on self care in relation to different stages of the disease and how such perception affected their lives. This is a qualitative study using oral history conducted with 15 older adults receiving palliative chemotherapy treatment in a health institution. The following categories emerged: social network, perspectives for confronting life, changes and spirituality. It is necessary for nursing staff to understand this process so that the measures implemented take into account all of the implications of the disease and aim at improving quality of life.   doi: 10.5216/ree.v16i2.22795.

  17. Graphene radio frequency receiver integrated circuit.

    Science.gov (United States)

    Han, Shu-Jen; Garcia, Alberto Valdes; Oida, Satoshi; Jenkins, Keith A; Haensch, Wilfried

    2014-01-01

    Graphene has attracted much interest as a future channel material in radio frequency electronics because of its superior electrical properties. Fabrication of a graphene integrated circuit without significantly degrading transistor performance has proven to be challenging, posing one of the major bottlenecks to compete with existing technologies. Here we present a fabrication method fully preserving graphene transistor quality, demonstrated with the implementation of a high-performance three-stage graphene integrated circuit. The circuit operates as a radio frequency receiver performing signal amplification, filtering and downconversion mixing. All circuit components are integrated into 0.6 mm(2) area and fabricated on 200 mm silicon wafers, showing the unprecedented graphene circuit complexity and silicon complementary metal-oxide-semiconductor process compatibility. The demonstrated circuit performance allow us to use graphene integrated circuit to perform practical wireless communication functions, receiving and restoring digital text transmitted on a 4.3-GHz carrier signal.

  18. VLBI2010 Receiver Back End Comparison

    Science.gov (United States)

    Petrachenko, Bill

    2013-01-01

    VLBI2010 requires a receiver back-end to convert analog RF signals from the receiver front end into channelized digital data streams to be recorded or transmitted electronically. The back end functions are typically performed in two steps: conversion of analog RF inputs into IF bands (see Table 2), and conversion of IF bands into channelized digital data streams (see Tables 1a, 1b and 1c). The latter IF systems are now completely digital and generically referred to as digital back ends (DBEs). In Table 2 two RF conversion systems are compared, and in Tables 1a, 1b, and 1c nine DBE systems are compared. Since DBE designs are advancing rapidly, the data in these tables are only guaranteed to be current near the update date of this document.

  19. Reducing the convective losses of cavity receivers

    Science.gov (United States)

    Flesch, Robert; Grobbel, Johannes; Stadler, Hannes; Uhlig, Ralf; Hoffschmidt, Bernhard

    2016-05-01

    Convective losses reduce the efficiency of cavity receivers used in solar power towers especially under windy conditions. Therefore, measures should be taken to reduce these losses. In this paper two different measures are analyzed: an air curtain and a partial window which covers one third of the aperture opening. The cavity without modifications and the usage of a partial window were analyzed in a cryogenic wind tunnel at -173°C. The cryogenic environment allows transforming the results from the small model cavity to a large scale receiver with Gr≈3.9.1010. The cavity with the two modifications in the wind tunnel environment was analyzed with a CFD model as well. By comparing the numerical and experimental results the model was validated. Both modifications are capable of reducing the convection losses. In the best case a reduction of about 50 % was achieved.

  20. Next Generation Radio Astronomy Receiver Systems

    CERN Document Server

    Morgan, Matthew A

    2009-01-01

    Radio astronomy observations in the coming decade will require new levels of sensitivity while mapping large regions of space with much greater efficiency than is achieved with current telescopes. This requires new instrumentation with the greatest achievable sensitivity, dynamic range, and field of view. Receiver noise is quickly approaching fundamental limits at most radio wavelengths, so significant gains in sensitivity can only be made by increasing collecting area. Jointly, these requirements suggest using large arrays of smaller antennas, or many moderate-size antennas equipped with multi-beam arrays. The challenge is to develop receivers and wide bandwidth data transport systems which are lower cost, more compact, more reliable, lower weight, and more reproducible than the best current systems, with no compromise to performance. This can be achieved with a greater degree of component integration, extensive use of digital signal processing and transport, and replacement of functions currently performed ...

  1. Digital Signal Processor For GPS Receivers

    Science.gov (United States)

    Thomas, J. B.; Meehan, T. K.; Srinivasan, J. M.

    1989-01-01

    Three innovative components combined to produce all-digital signal processor with superior characteristics: outstanding accuracy, high-dynamics tracking, versatile integration times, lower loss-of-lock signal strengths, and infrequent cycle slips. Three components are digital chip advancer, digital carrier downconverter and code correlator, and digital tracking processor. All-digital signal processor intended for use in receivers of Global Positioning System (GPS) for geodesy, geodynamics, high-dynamics tracking, and ionospheric calibration.

  2. Armstrong Receives Space Medal of Honor

    Science.gov (United States)

    1978-01-01

    Astronaut Neil A. Armstrong receives the first Congressional Space Medal of Honor from President Jimmy Carter, assisted by Captain Robert Peterson. Armstrong, one of six astronauts to be presented the medal during ceremonies held in the Vehicle Assembly Building (VAB), was awarded for his performance during the Gemini 8 mission and the Apollo 11 mission when he became the first human to set foot upon the Moon.

  3. Optical antenna gain. II - Receiving antennas

    Science.gov (United States)

    Degnan, J. J.; Klein, B. J.

    1974-01-01

    Expressions are developed for the gain of a centrally obscured, circular optical antenna used as the collecting and focusing optics in a laser receiver, involving losses due to (1) incoming light blockage by central obscuration, (2) energy spillover at the detector, and (3) the effect of local oscillator distribution in the case of heterodyne or homodyne detection. Numerical results are presented for direct detection and for three types of local oscillator distribution (uniform, Gaussian, and matched).

  4. Counterrotator And Correlator For GPS Receivers

    Science.gov (United States)

    Thomas, J. Brooks; Srinivasan, Jeffrey M.; Meehan, Thomas K.

    1989-01-01

    Accurate, all-digital, high-speed processor comprising correlator and down-converter developed for receivers in Global Positioning System (GPS). Processor reduces roundoff and commensurability errors to extremely small values. Use of digital chip and phase advancers provides outstanding control and accuracy in phase and feedback. Great flexibility imparted by provision for arbitrary starting time and integration length. Minimum-bit design requires minimum number of logical elements, thereby reducing size, power, and cost.

  5. Receiver Function Analysis of the Eastern Tennessee Seismic Zone

    Science.gov (United States)

    Graw, J. H.; Powell, C. A.; Langston, C. A.

    2011-12-01

    We present receiver/transfer functions determined for a seismic network associated with an active, intraplate seismic zone. Basement studies within eastern Tennessee are sparse despite the fact that these rocks host the eastern Tennessee seismic zone (ETSZ) and are associated with an extensive aeromagnetic lineament called the New York-Alabama (NY-AL) lineament. The NY-AL lineament is prominent in eastern Tennessee, with a SW-NE trend, and is characterized by a lateral change in magnetic and gravity anomalies in a NW to SE direction; high magnetic and low gravity anomalies lie west of the lineament, while low magnetic and high gravity anomalies are located east of the lineament. The NY-AL lineament is thought to be an ancient strike-slip fault that is reactivating in the present day stress field. A better understanding of the basement structure within the ETSZ will aid in the assessment of its seismic hazard potential. A network maintained by the Center for Earthquake Research and Information (CERI) at the University of Memphis is located within the study area and consists of 23 short-period and three broadband seismometers. An additional station (TZTN) is maintained by IRIS and is included in our dataset. Receiver functions are computed using teleseismic earthquakes within a 30°-90° epicentral distance, at hypocentral depths greater than 30 km, and with magnitudes greater than Mw 6.0. A vertical component stack is used to obtain the best source function. A spectral waterlevel deconvolution is then used to calculate the receiver functions. Results indicate a thickening of the crust west of the NY-AL lineament and show vertical variation within the crust and upper mantle with abrupt polarity changes and strong positive and negative amplitude values. Crustal structure west of the NY-AL lineament appears to be much more complex than that east of the NY-AL lineament.

  6. Optical antenna gain. 2: receiving antennas.

    Science.gov (United States)

    Degnan, J J; Klein, B J

    1974-10-01

    Expressions are derived for the gain of a centrally obscured, circular optical antenna when used as the collecting and focusing optics in a laser receiver which include losses due to (1) blockage of the incoming light by the central obscuration, (2) the spillover of energy at the detector, and (3) the effect of local oscillator distribution in the case of heterodyne or homodyne detection. Numerical results are presented for direct detection and for three types of local oscillator distributions (uniform, Gaussian, and matched) in the case of heterodyne or homodyne detection. The results are presented in several graphs that allow the rapid evaluation of receiver gain for an arbitrary set of telescope and detector parameters. It is found that, for uniform illumination by the LO, the optimum SNR is obtained when the detector radius is approximately 0.74 times the Airy disk radius. The use of an optimized Gaussian (spot size = 0.46 times the Airy disk radius) improves the receiver gain by less than 1 dB. Theuse results are insensitive to the size of the central obscuration.

  7. Transient simulation of molten salt central receiver

    Science.gov (United States)

    Doupis, Dimitri; Wang, Chuan; Carcorze-Soto, Jorge; Chen, Yen-Ming; Maggi, Andrea; Losito, Matteo; Clark, Michael

    2016-05-01

    Alstom is developing concentrated solar power (CSP) utilizing 60/40wt% NaNO3-KNO3 molten salt as the working fluid in a tower receiver for the global renewable energy market. In the CSP power generation cycle, receivers undergo a daily cyclic operation due to the transient nature of solar energy. Development of robust and efficient start-up and shut-down procedures is critical to avoiding component failures due to mechanical fatigue resulting from thermal transients, thus maintaining the performance and availability of the CSP plant. The Molten Salt Central Receiver (MSCR) is subject to thermal transients during normal daily operation, a cycle that includes warmup, filling, operation, draining, and shutdown. This paper describes a study to leverage dynamic simulation and finite element analysis (FEA) in development of start-up, shutdown, and transient operation concepts for the MSCR. The results of the FEA also verify the robustness of the MSCR design to the thermal transients anticipated during the operation of the plant.

  8. Development of Receiver Stimulator for Auditory Prosthesis

    Directory of Open Access Journals (Sweden)

    K. Raja Kumar

    2010-05-01

    Full Text Available The Auditory Prosthesis (AP is an electronic device that can provide hearing sensations to people who are profoundly deaf by stimulating the auditory nerve via an array of electrodes with an electric current allowing them to understand the speech. The AP system consists of two hardware functional units such as Body Worn Speech Processor (BWSP and Receiver Stimulator. The prototype model of Receiver Stimulator for Auditory Prosthesis (RSAP consists of Speech Data Decoder, DAC, ADC, constant current generator, electrode selection logic, switch matrix and simulated electrode resistance array. The laboratory model of speech processor is designed to implement the Continuous Interleaved Sampling (CIS speech processing algorithm which generates the information required for electrode stimulation based on the speech / audio data. Speech Data Decoder receives the encoded speech data via an inductive RF transcutaneous link from speech processor. Twelve channels of auditory Prosthesis with selectable eight electrodes for stimulation of simulated electrode resistance array are used for testing. The RSAP is validated by using the test data generated by the laboratory prototype of speech processor. The experimental results are obtained from specific speech/sound tests using a high-speed data acquisition system and found satisfactory.

  9. Russian institute receives CMS Gold Award

    CERN Multimedia

    Patrice Loïez

    2003-01-01

    The Snezhinsk All-Russian Institute of Scientific Research for Technical Physics (VNIITF) of the Russian Federal Nuclear Centre (RFNC) is one of twelve CMS suppliers to receive awards for outstanding performance this year. The CMS Collaboration took the opportunity of the visit to CERN of the Director of VNIITF and his deputy to present the CMS Gold Award, which the institute has received for its exceptional performance in the assembly of steel plates for the CMS forward hadronic calorimeter. This calorimeter consists of two sets of 18 wedge-shaped modules arranged concentrically around the beam-pipe at each end of the CMS detector. Each module consists of steel absorber plates with quartz fibres inserted into them. The institute developed a special welding technique to assemble the absorber plates, enabling a high-quality detector to be produced at relatively low cost.RFNC-VNIITF Director Professor Georgy Rykovanov (right), is seen here receiving the Gold Award from Felicitas Pauss, Vice-Chairman of the CMS ...

  10. Redotex ingestions reported to Texas poison centers.

    Science.gov (United States)

    Forrester, Mathias B

    2010-09-01

    Although the multi-component weight loss supplement Redotex is banned in the United States, the supplement can be obtained in Mexico. The intent of this report was to describe the pattern of Redotex calls received by a statewide poison center system. Cases were all Redotex calls received by Texas poison centers during 2000-2008. The distribution of total calls and those involving ingestion of the supplement were determined for selected demographic and clinical factors. Of 34 total Redotex calls received, 55.9% came from the 14 Texas counties that border Mexico. Of the 22 reported Redotex ingestions, 77.3% of the patients were female and 45.5% 20 years or more. Of the 17 ingestions involving no co-ingestants, 52.9% were already at or en route to a health care facility, 41.2% were managed on site, and 5.9% was referred to a health care facility. The final medical outcome was no effect in 23.5% cases, minor effect in 5.9%, moderate effect in 11.8%, not followed but minimal clinical effects possible in 47.1%, and unable to follow but judged to be potentially toxic in 11.8%. Most Redotex calls to the Texas poison center system originated from counties bordering Mexico.

  11. National Farm Medicine Center

    Science.gov (United States)

    Research Areas Applied Sciences Biomedical Informatics Clinical Research Epidemiology Farm Medicine Human Genetics Oral-Systemic Health Clinical ... Consulting Agritourism Farm MAPPER Lyme Disease ROPS Rebate Zika Virus National Farm Medicine Center The National Farm ...

  12. Mental Health Screening Center

    Science.gov (United States)

    ... Releases & Announcements Public Service Announcements Partnering with DBSA Mental Health Screening Center These online screening tools are not ... you have any concerns, see your doctor or mental health professional. Depression This screening form was developed from ...

  13. Carbon Monoxide Information Center

    Medline Plus

    Full Text Available ... CONSUMER PRODUCT SAFETY COMMISSION Search CPSC Search Menu Home Recalls Recall List CPSC Recall API Recall Lawsuits ... and Bans Report an Unsafe Product Consumers Businesses Home Safety Education Safety Education Centers Carbon Monoxide Information ...

  14. USU Patient Simulation Center

    Data.gov (United States)

    Federal Laboratory Consortium — he National Capital Area (NCA) Medical Simulation Center is a state-of-the-art training facility located near the main USU campus. It uses simulated patients (i.e.,...

  15. Global Hydrology Research Center

    Data.gov (United States)

    National Aeronautics and Space Administration — The GHRC is the data management and user services arm of the Global Hydrology and Climate Center. It encompasses the data and information management, supporting...

  16. National Automotive Center - NAC

    Data.gov (United States)

    Federal Laboratory Consortium — Encouraged by the advantages of collaboration, the U.S. Army Tank Automotive Research, Development and Engineering Center (TARDEC) worked with the Secretary of the...

  17. Reliability Centered Maintenance - Methodologies

    Science.gov (United States)

    Kammerer, Catherine C.

    2009-01-01

    Journal article about Reliability Centered Maintenance (RCM) methodologies used by United Space Alliance, LLC (USA) in support of the Space Shuttle Program at Kennedy Space Center. The USA Reliability Centered Maintenance program differs from traditional RCM programs because various methodologies are utilized to take advantage of their respective strengths for each application. Based on operational experience, USA has customized the traditional RCM methodology into a streamlined lean logic path and has implemented the use of statistical tools to drive the process. USA RCM has integrated many of the L6S tools into both RCM methodologies. The tools utilized in the Measure, Analyze, and Improve phases of a Lean Six Sigma project lend themselves to application in the RCM process. All USA RCM methodologies meet the requirements defined in SAE JA 1011, Evaluation Criteria for Reliability-Centered Maintenance (RCM) Processes. The proposed article explores these methodologies.

  18. HUD Homeownership Centers

    Data.gov (United States)

    Department of Housing and Urban Development — HUD Homeownership Centers (HOCs) insure single family Federal Housing Administration (FHA) mortgages and oversee the selling of HUD homes. FHA has four Homeownership...

  19. Hazardous Waste Research Center

    Data.gov (United States)

    Federal Laboratory Consortium — A full-service research and evaluation center equipped with safety equipment, a high-bay pilot studies area, and a large-scale pilot studies facility The U.S. Army...

  20. World Trade Center

    Index Scriptorium Estoniae

    2006-01-01

    Esilinastus katastroofifilm "World Trade Center" : stsenarist Andrea Berloff : režissöör Oliver Stone : kunstnik Jan Roelfs : osades Nicholas Cage, Michael Pena, Stephen Dorff jpt : Ameerika Ühendriigid 2006. Ka filmi prototüüpidest

  1. Health Center Controlled Network

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Health Center Controlled Network (HCCN) tool is a locator tool designed to make data and information concerning HCCN resources more easily available to our...

  2. The ORFEUS Data Center

    Directory of Open Access Journals (Sweden)

    B. Dost

    1994-06-01

    Full Text Available 1993 the ORFEUS Data Center (ODC; Dost, 1991 changed hosting organisation. It moved within the Netherlands from the University of Utrecht to the Royal Netherlands Meteorological Institute (KNM1 in de Bilt. This change in hosting organisation was necessary to ensure a longer term stability in the operation of the ODC. Key issues for the ODC are the rapid on-line data access and quality controlled, complete and efficient off-line data access. During 1992 the ODC became the European node in the international SPYDER system which provides near real-time access to digital broadband data from selected high quality stations. Electronic messages trigger soveral centers well distributed over the globe. These centers then collect the data by modem from selected stations in their region. Finally, data are distributed between data centers over internet.

  3. Advanced data center economy

    OpenAIRE

    Sukhov, R.; Amzarakov, M.; E. Isaev

    2013-01-01

    The article addresses basic Data Centers (DC) drivers of price and engineering, which specify rules and price evaluation for creation and further operation. DC energy efficiency concept, its influence on DC initial price, operation costs and Total Cost of Ownership.

  4. World Trade Center

    Index Scriptorium Estoniae

    2006-01-01

    Esilinastus katastroofifilm "World Trade Center" : stsenarist Andrea Berloff : režissöör Oliver Stone : kunstnik Jan Roelfs : osades Nicholas Cage, Michael Pena, Stephen Dorff jpt : Ameerika Ühendriigid 2006. Ka filmi prototüüpidest

  5. Carbon Monoxide Information Center

    Medline Plus

    Full Text Available ... Community Outreach Resource Center Toy Recall Statistics CO Poster Contest Pool Safely Business & Manufacturing Business & Manufacturing Business ... Featured Resources CPSC announces winners of carbon monoxide poster contest Video View the blog Clues You Can ...

  6. Cooperative Tagging Center (CTC)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Cooperative Tagging Center (CTC) began as the Cooperative Game Fish Tagging Program (GTP) at Woods Hole Oceanographic Institute (WHOI) in 1954. The GTP was...

  7. NMA Analysis Center

    Science.gov (United States)

    Kierulf, Halfdan Pascal; Andersen, Per Helge

    2013-01-01

    The Norwegian Mapping Authority (NMA) has during the last few years had a close cooperation with Norwegian Defence Research Establishment (FFI) in the analysis of space geodetic data using the GEOSAT software. In 2012 NMA has taken over the full responsibility for the GEOSAT software. This implies that FFI stopped being an IVS Associate Analysis Center in 2012. NMA has been an IVS Associate Analysis Center since 28 October 2010. NMA's contributions to the IVS as an Analysis Centers focus primarily on routine production of session-by-session unconstrained and consistent normal equations by GEOSAT as input to the IVS combined solution. After the recent improvements, we expect that VLBI results produced with GEOSAT will be consistent with results from the other VLBI Analysis Centers to a satisfactory level.

  8. Center for Women Veterans

    Science.gov (United States)

    ... 2014-2020 VA Plans, Budget, & Performance VA Claims Representation RESOURCES Careers at VA Employment Center Returning Service Members Vocational Rehabilitation & Employment Homeless Veterans Women Veterans Minority Veterans Plain Language Surviving Spouses & Dependents ...

  9. Centering in Japanese Discourse

    CERN Document Server

    Walker, M; Côté, S; Walker, Marilyn; Iida, Masayo; Cote, Sharon

    1996-01-01

    In this paper we propose a computational treatment of the resolution of zero pronouns in Japanese discourse, using an adaptation of the centering algorithm. We are able to factor language-specific dependencies into one parameter of the centering algorithm. Previous analyses have stipulated that a zero pronoun and its cospecifier must share a grammatical function property such as {\\sc Subject} or {\\sc NonSubject}. We show that this property-sharing stipulation is unneeded. In addition we propose the notion of {\\sc topic ambiguity} within the centering framework, which predicts some ambiguities that occur in Japanese discourse. This analysis has implications for the design of language-independent discourse modules for Natural Language systems. The centering algorithm has been implemented in an HPSG Natural Language system with both English and Japanese grammars.

  10. Accredited Birth Centers

    Science.gov (United States)

    ... 9743 Accredited since January 2016 98 Bright Eyes Midwifery and Wild Rivers Women's Health Accredited 29135 Ellensburg ... Accredited since November 2015 96 Footprints in Time Midwifery Services and Birth Center Accredited 351 N. Water ...

  11. FEMA Disaster Recovery Centers

    Data.gov (United States)

    Department of Homeland Security — This is a search site for FEMA's Disaster Recovery Centers (DRC). A DRC is a readily accessible facility or mobile office set up by FEMA where applicants may go for...

  12. Center for Contaminated Sediments

    Data.gov (United States)

    Federal Laboratory Consortium — The U.S. Army Corps of Engineers Center for Contaminated Sediments serves as a clearinghouse for technology and expertise concerned with contaminated sediments. The...

  13. Center Innovation Fund Program

    Data.gov (United States)

    National Aeronautics and Space Administration — To stimulate and encourage creativity and innovation within the NASA Centers. The activities are envisioned to fall within the scope of NASA Space Technology or...

  14. Advanced Missile Signature Center

    Data.gov (United States)

    Federal Laboratory Consortium — The Advanced Missile Signature Center (AMSC) is a national facility supporting the Missile Defense Agency (MDA) and other DoD programs and customers with analysis,...

  15. Test Control Center

    Science.gov (United States)

    2000-01-01

    At the test observation periscope in the Test Control Center exhibit in StenniSphere at the John C. Stennis Space Center in Hancock County, Miss., visitors can observe a test of a Space Shuttle Main Engine exactly as test engineers might see it during a real engine test. The Test Control Center exhibit exactly simulates not only the test control environment, but also the procedure of testing a rocket engine. Designed to entertain while educating, StenniSphere includes informative dispays and exhibits from NASA's lead center for rocket propulsion and remote sensing applications. StenniSphere is open free of charge from 9 a.m. to 5 p.m. daily.

  16. Oil Reserve Center Established

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Like other countries,China has started to grow its strategic oil reserve in case oil supplies are cut On December 18,2007,the National Development and Reform Commission(NDRC),China’s top economic planner,announced that the national oil reserve center has been officially launched.The supervisory system over the oil reserves has three levels: the energy department of the NDRC,the oil reserve center,and the reserve bases.

  17. National Biocontainment Training Center

    Science.gov (United States)

    2015-08-01

    than ever before as scientists push to understand the pathology and develop diagnostics, vaccines and therapeutics for deadly diseases like Ebola...Hardcastle, Vickie Jones, Sheri Leavitt, and Belinda Rivera. Gulf Coast Consortium Postdoctoral Veterinary Training Program - A clinical veterinarian from...the Center for Comparative Medicine at Baylor College of Medicine in Houston and a veterinarian from the University of Texas Health Science Center

  18. Data center cooling system

    Energy Technology Data Exchange (ETDEWEB)

    Chainer, Timothy J; Dang, Hien P; Parida, Pritish R; Schultz, Mark D; Sharma, Arun

    2015-03-17

    A data center cooling system may include heat transfer equipment to cool a liquid coolant without vapor compression refrigeration, and the liquid coolant is used on a liquid cooled information technology equipment rack housed in the data center. The system may also include a controller-apparatus to regulate the liquid coolant flow to the liquid cooled information technology equipment rack through a range of liquid coolant flow values based upon information technology equipment temperature thresholds.

  19. Activity report of Mechanical Engineering Center

    Energy Technology Data Exchange (ETDEWEB)

    1997-07-01

    On April 1997, National Laboratory for High Energy Physics (KEK), Institute of Nuclear Study, University of Tokyo (INS), and Meson Science Laboratory; Faculty of Science, University of Tokyo began to work newly as High Energy Accelerator Research Organization after reconstructing and converting their systems, under aiming at further development of a wide field of accelerator science using a high energy accelerator. Hitherto, the large scale research plans of accelerator at the KEK have been not only received their relation communities on learning importance, meanings and social factors from their stages, but also promoted carefully under opinions and evaluation of outer objective ones and received outer serious evaluations for established research results either. Mechanical Engineering Center belonging to Applied Research Laboratory in the new Organization, started under jointing some sections relating to KEK and INS. As separately operating at the old organization engineering center in Tsukuba area and at engineering room in Tanashi Laboratory for some years, the Center was intended to integrate after 2000 to use this evaluation results for future development. This report was prepared separately on actions at the old engineering center of KEK as its first section and the engineering room of INS as its second section. (G.K.)

  20. Presentation of the Western Danish Sexual Assault Center

    DEFF Research Database (Denmark)

    Hansen, Ole Ingemann

    a psychologist will contact the victim. At the moment the victims are offered follow-up by the psychologist, at the department of gynaecology or by their own general practitioner. The Center covers an area of 890.000 people. From 1999 to 2004 the Center received 523 victims. 330 (63%) were seen by the physician...... - the others were taken care of by the nurses and/or the psychologist. 256 victims examined by the physicians were reported to the police (78%). The Aarhus Center is now well established, and there is an excellent cooperation in the region between the Center and the affiliated partners: the police...

  1. Solar receiver performance of point focusing collector system

    Science.gov (United States)

    Wu, Y. C.; Wen, L. C.

    1978-01-01

    The solar receiver performance of cavity receivers and external receivers used in dispersed solar power systems was evaluated for the temperature range 300-1300 C. Several parameters of receiver and concentrator are examined. It was found that cavity receivers are generally more efficient than external receivers, especially at high temperatures which require a large heat transfer area. The effects of variation in the ratio of receiver area to aperture area are considered.

  2. Thatcher Receives 2004 Charles A. Whitten Medal

    Science.gov (United States)

    Stein, Ross

    2005-02-01

    Wayne Thatcher received the Whitten Medal at the 2004 Fall Meeting Honors Ceremony on 15 December, in San Francisco, California. The medal is given for outstanding achievement in research on the form and dynamics of the Earth and planets. Citation. Armed with geodesy, Wayne Thatcher has probed the behavior of great earthquakes, concentrating on the two sites where large events are frequent and the geodetic record is lush: the western United States and Japan. From this, he has garnered deep insights into the earthquake cycle-the pattern of strain accumulation and release of which an earthquake is only the most visible part.

  3. Multi-antenna synchronized global navigation satellite system receiver and its advantages in high-precision positioning applications

    Science.gov (United States)

    Dong, Danan; Chen, Wen; Cai, Miaomiao; Zhou, Feng; Wang, Minghua; Yu, Chao; Zheng, Zhengqi; Wang, Yuanfei

    2016-12-01

    The multi-antenna synchronized global navigation satellite system receiver is a high precision, low cost, and widely used emerging receiver. Using this type of receiver, the satellite and receiver clock errors can be eliminated simultaneously by forming between antenna single-differences, which is equivalent to the conventional double-difference model. However, current multi-antenna synchronized global navigation satellite system receiver products have not fully realized their potential to achieve better accuracy, efficiency, and broader applications. This paper introduces the conceptual design and derivable products of multi-antenna synchronized global navigation satellite system receivers involving the aspects of attitude determination, multipath effect mitigation, phase center variation correction, and ground-based carrier phase windup calibration. Through case studies, the advantages of multi-antenna synchronized global navigation satellite system receivers in high-precision positioning applications are demonstrated.

  4. Perspectives from older adults receiving cancer treatment about the cancer-related information they receive

    OpenAIRE

    2015-01-01

    Objective: Cancer patients have reported that information plays a significant role in their capacity to cope with cancer and manage the consequences of treatment. This study was undertaken to identify the importance older adults receiving cancer treatment assign to selected types of cancer-related information, their satisfaction with the cancer-related information they received, and the barriers to effective information provision for this age group. Methods: This study was conducted in two ph...

  5. Omnidirectional free-space optical receiver architecture

    Science.gov (United States)

    Murshid, Syed H.; Lovell, Gregory L.; Finch, Michael F.

    2013-05-01

    Free Space Optical (FSO) communication is the fusion of wireless technology and optical fiber communications systems. It has the potential of providing fiber optic data rates without the physical restraints of optical fiber cables. This endeavor presents a novel receiver structure with potential for omnidirectional free space optical communications. Interesting approaches for accomplishing omnidirectional free space lasercomm such as direct detection and solar blind non-line of sight UV scattering have been reported over the last few years. However, these technologies have resulted in limited distances of the order of 10 to 100 meters and data rates often limited to less than 1 Mb/s. This endeavor reports the architecture of an omnidirectional receiver setup by integrating an off the shelf detector and a fiber bundle, where the fiber bundle couples omnidirectional photons within its field of view and delivers these photons to the detector. The coupling of light from all directions into a detector is regulated by the cone of the acceptance angle of the fiber. Multiple fibers with overlapping acceptance angles provide the necessary coverage that may be needed to extract the optical signal from the free space optical channel. Simulated results showing the normalized power pattern of the system is presented to demonstrate omnidirectional potential of the structure. Theoretical power level versus distance plot for an FSO System employing On-O Keying (OOK) is also presented.

  6. Woese on the received view of evolution.

    Science.gov (United States)

    Sarkar, Sahotra

    2014-01-01

    As part of his attempt to reconstruct the earliest phase of the evolution of life on Earth, Woese produced a compelling critique of the received view of evolution from the 20th century. This paper explicitly articulates two related features of that critique that are fundamental but the first of which has not been sufficiently clearly recognized in the context of evolutionary theorizing: (1) according to Woese's scenario of communal evolution during life's earliest phase (roughly, the first billion years of life on Earth), well-defined biological individuals (and, thus, individual lineages) did not exist; and (2) during that phase, evolutionary change took place through ubiquitous horizontal gene transfer (HGT) rather than through vertical transmission of features (including genes) and the combinatorics of HGT was the dominant mechanism of evolutionary change. Both factors present serious challenges to the received view of evolution and that framework would have to be radically altered to incorporate these factors. The extent to which this will be necessary will depend on whether Woese's scenario of collective early evolution is correct.

  7. Parabolic Trough Receiver Heat Loss Testing (Poster)

    Energy Technology Data Exchange (ETDEWEB)

    Price, H.; Netter, J.; Bingham, C.; Kutscher, C.; Burkholder, F.; Brandemuehl, M.

    2007-03-01

    Parabolic trough receivers, or heat collection elements (HCEs), absorb sunlight focused by the mirrors and transfer that thermal energy to a fluid flowing within them. Thje absorbing tube of these receivers typically operates around 400 C (752 F). HCE manufacturers prevent thermal loss from the absorbing tube to the environment by using sputtered selective Cermet coatings on the absorber and by surrounding the absorber with a glass-enclosed evacuated annulus. This work quantifies the heat loss of the Solel UVAC2 and Schott PTR70 HCEs. At 400 C, the HCEs perform similarly, losing about 400 W/m of HCE length. To put this in perspective, the incident beam radiation on a 5 m mirror aperture is about 4500 W/m, with about 75% of that energy ({approx} 3400 W/m) reaching the absorber surface. Of the 3400 W/m on the absorber, about 3000 W/m is absorbed into the working fluid while 400 W/m is lost to the environment.

  8. Solar central receiver heliostat reflector assembly

    Science.gov (United States)

    Horton, Richard H.; Zdeb, John J.

    1980-01-01

    A heliostat reflector assembly for a solar central receiver system comprises a light-weight, readily assemblable frame which supports a sheet of stretchable reflective material and includes mechanism for selectively applying tension to and positioning the sheet to stretch it to optical flatness. The frame is mounted on and supported by a pipe pedestal assembly that, in turn, is installed in the ground. The frame is controllably driven in a predetermined way by a light-weight drive system so as to be angularly adjustable in both elevation and azimuth to track the sun and efficiently continuously reflect the sun's rays to a focal zone, i.e. central receiver, which forms part of a solar energy utilization system, such as a solar energy fueled electrical power generation system. The frame may include a built-in system for testing for optical flatness of the reflector. The preferable geometric configuration of the reflector is octagonal; however, it may be other shapes, such as hexagonal, pentagonal or square. Several different embodiments of means for tensioning and positioning the reflector to achieve optical flatness are disclosed. The reflector assembly is based on the stretch frame concept which provides an extremely light-weight, simple, low-cost reflector assembly that may be driven for positioning and tracking by a light-weight, inexpensive drive system.

  9. Transactions Security Tools in Account Receivables Management

    Directory of Open Access Journals (Sweden)

    Anna Wodyńska

    2008-03-01

    Full Text Available Large competition among goods and services suppliers caused that granting clients deferred term of payment became a standard, so in other word granting clients commercial credit is a standard. Companies try to limit credit risk by securing their trade transactions in accordance with their credit policy that determines in some way the choice of trade transaction security tools.This article presents a full range of trade transaction security tools according to the general division into personal and property securities. The author pays attention to the fact that while conducting a proper credit policy in relation to clients, a company has chances to monitor efficiently the receivables and insist on their payment as well as use, as needed, the earlier prepared trade transaction security tools.The author convinces that regardless of the choice of trade transaction security tools, or reasons leading the receivables managing person, the basic criterion of security evaluation shall be its real, checked and verified value. The pledge on an object that does not exist is not worth much. The same applies to security granted by an insolvent person.

  10. The Submillimeter Array Antennas and Receivers

    CERN Document Server

    Blundell, R

    2005-01-01

    The Submillimeter Array (SMA) was conceived at the Smithsonian Astrophysical Observatory in 1984 as a six element interferometer to operate in the major atmospheric windows from about 200 to 900 GHz. In 1996, the Academica Sinica Institute of Astronomy and Astrophysics of Taiwan joined the project and agreed to provide additional hardware to expand the interferometer to eight elements. All eight antennas are now operating at the observatory site on Mauna Kea, and astronomical observations have been made in the 230, 345, and 650 GHz bands. The SMA antennas have a diameter of 6 m, a surface accuracy of better than 25 micron rms, and can be reconfigured to provide spatial resolutions down to about 0.5" at 200 GHz and, eventually, 0.1" at 850 GHz. Coupling to the receiver package within each antenna is achieved via a beam waveguide, in a bent Nasmyth configuration, comprised of a flat tertiary mirror and two ellipsoidal mirrors that form a secondary pupil used for receiver calibration. An additional fixed mirror ...

  11. "Infotonics Technology Center"

    Energy Technology Data Exchange (ETDEWEB)

    Fritzemeier, L. [Infotonics Technology Center Inc., Canandaigua, NY (United States); Boysel, M. B. [Infotonics Technology Center Inc., Canandaigua, NY (United States); Smith, D. R. [Infotonics Technology Center Inc., Canandaigua, NY (United States)

    2004-09-30

    During this grant period July 15, 2002 thru September 30, 2004, the Infotonics Technology Center developed the critical infrastructure and technical expertise necessary to accelerate the development of sensors, alternative lighting and power sources, and other specific subtopics of interest to Department of Energy. Infotonics fosters collaboration among industry, universities and government and operates as a national center of excellence to drive photonics and microsystems development and commercialization. A main goal of the Center is to establish a unique, world-class research and development facility. A state-of-the-art microsystems prototype and pilot fabrication facility was established to enable rapid commercialization of new products of particular interest to DOE. The Center has three primary areas of photonics and microsystems competency: device research and engineering, packaging and assembly, and prototype and pilot-scale fabrication. Center activities focused on next generation optical communication networks, advanced imaging and information sensors and systems, micro-fluidic systems, assembly and packaging technologies, and biochemical sensors. With targeted research programs guided by the wealth of expertise of Infotonics business and scientific staff, the fabrication and packaging facility supports and accelerates innovative technology development of special interest to DOE in support of its mission and strategic defense, energy, and science goals.

  12. Engineer Research and Development Center's Materials Testing Center (MTC)

    Data.gov (United States)

    Federal Laboratory Consortium — The Engineer Research and Development Center's Materials Testing Center (MTC) is committed to quality testing and inspection services that are delivered on time and...

  13. The delivery dispatching problem with time windows for urban consolidation centers

    NARCIS (Netherlands)

    van Heeswijk, W.J.A.; Mes, Martijn R.K.; Schutten, Johannes M.J.

    2015-01-01

    This paper addresses the dispatch decision problem faced by an urban consolidation center. The center receives orders according to a stochastic arrival process, and dispatches them for the last-mile distribution in batches. The operator of the center aims to fi nd the cost-minimizing consolidation

  14. High sensitivity broadband 360GHz passive receiver for TeraSCREEN

    Science.gov (United States)

    Wang, Hui; Oldfield, Matthew; Maestrojuán, Itziar; Platt, Duncan; Brewster, Nick; Viegas, Colin; Alderman, Byron; Ellison, Brian N.

    2016-05-01

    TeraSCREEN is an EU FP7 Security project aimed at developing a combined active, with frequency channel centered at 360 GHz, and passive, with frequency channels centered at 94, 220 and 360 GHz, imaging system for border controls in airport and commercial ferry ports. The system will include automatic threat detection and classification and has been designed with a strong focus on the ethical, legal and practical aspects of operating in these environments and with the potential threats in mind. Furthermore, both the passive and active systems are based on array receivers with the active system consisting of a 16 element MIMO FMCW radar centered at 360 GHz with a bandwidth of 30 GHz utilizing a custom made direct digital synthesizer. The 16 element passive receiver system at 360 GHz uses commercial Gunn diode oscillators at 90 GHz followed by custom made 90 to 180 GHz frequency doublers supplying the local oscillator for 360 GHz sub-harmonic mixers. This paper describes the development of the passive antenna module, local oscillator chain, frequency mixers and detectors used in the passive receiver array of this system. The complete passive receiver chain is characterized in this paper.

  15. International Water Center

    Science.gov (United States)

    The urban district of Nancy and the Town of Nancy, France, have taken the initiative of creating an International Center of Water (Centre International de l'Eau à Nancy—NAN.C.I.E.) in association with two universities, six engineering colleges, the Research Centers of Nancy, the Rhine-Meuse Basin Agency, and the Chamber of Commerce and Industry. The aim of this center is to promote research and technology transfer in the areas of water and sanitation. In 1985 it will initiate a research program drawing on the experience of 350 researchers and engineers of various disciplines who have already been assigned to research in these fields. The research themes, the majority of which will be multidisciplinary, concern aspects of hygiene and health, the engineering of industrial processes, water resources, and the environment and agriculture. A specialist training program offering five types of training aimed at university graduates, graduates of engineering colleges, or experts, will start in October 1984.

  16. PTSD: National Center for PTSD

    Medline Plus

    Full Text Available ... Vet Centers) War Related Illness & Injury Study Center Homeless Veterans Returning Service Members Rural Veterans Seniors & Aging ... Employment Center Returning Service Members Vocational Rehabilitation & Employment Homeless Veterans Women Veterans Minority Veterans Plain Language Surviving ...

  17. Hospitals report on cancer centers.

    Science.gov (United States)

    Rees, T

    2001-01-01

    Woman's Hospital, Baton Rouge, La., is first-place winner among cancer centers. Holy Cross Hospital's Michael and Dianne Bienes Comprehensive Cancer Center, Ft. Lauderdale, Fla., is named second; and, Cardinal Health System's Ball Cancer Center, Muncie, Ind., third.

  18. Patient-centered Care.

    Science.gov (United States)

    Reynolds, April

    2009-01-01

    Patient-centered care focuses on the patient and the individual's particular health care needs. The goal of patient-centered health care is to empower patients to become active participants in their care. This requires that physicians, radiologic technologists and other health care providers develop good communication skills and address patient needs effectively. Patient-centered care also requires that the health care provider become a patient advocate and strive to provide care that not only is effective but also safe. For radiologic technologists, patient-centered care encompasses principles such as the as low as reasonably achievable (ALARA) concept and contrast media safety. Patient-centered care is associated with a higher rate of patient satisfaction, adherence to suggested lifestyle changes and prescribed treatment, better outcomes and more cost-effective care. This article is a Directed Reading. Your access to Directed Reading quizzes for continuing education credit is determined by your area of interest. For access to other quizzes, go to www.asrt.org/store. According to one theory, most patients judge the quality of their healthcare much like they rate an airplane flight. They assume that the airplane is technically viable and is being piloted by competent people. Criteria for judging a particular airline are personal and include aspects like comfort, friendly service and on-time schedules. Similarly, patients judge the standard of their healthcare on nontechnical aspects, such as a healthcare practitioner's communication and "soft skills." Most are unable to evaluate a practitioner's level of technical skill or training, so the qualities they can assess become of the utmost importance in satisfying patients and providing patient-centered care.(1).

  19. Eosinophils increase in animals that received biotherapic

    Directory of Open Access Journals (Sweden)

    Pedro Gilberto Silva Morais

    2012-12-01

    Full Text Available Dairy industry is an important Brazilian economic activity participating of income generation. European breeds cattle aren’t adapted to parasites found in the tropics, like the Rhipicephalus microplus tick. Parasites can acquire resistance to allopathic products, but not to homeopathic products. We evaluate the efficacy of an antiparasiticide biotherapic against the R. microplus tick. The biotherapic was prepared according to the homeopathic pharmacopoeia recommendations from vegetable (Abrotanum and animal products (Rhipicephalus microplus, Amblyomma cajenennense, Haematobia irritans, Musca domestica, Dermatobia hominis, all diluted and vigorous shaken (dynamized in water or alcohol at a ratio of 1:99, in the 12th Centesimal Hahnemann (CH12, with limestone as the carrier. This homeophatic product found in veterinary pharmacies of Ituiutaba’s region, Minas Gerais State, is registered at Ministério da Agricultura, Pecuária e Abastecimento (MAPA. Natural tick infestation was accessed in thirty Girolando (Gir x Holstein cows with 7 to 13 year-old, by monthly counting of tick female bigger than 6 mm, from October/2009 to July/2011. Cows were divided in three groups of 10 similar animals. The treated group (T1 received roughage, concentrate and biotherapic. The placebo group (T2 received roughage, concentrate and limestone and the control group (T3 received only roughage and concentrate. T1 and T2 groups were managed together and remained in the same paddock. T3 group was separed from T1 and T2 by a wire fence. From October 2009 to September 2010 blood cell counts and serum biochemical tests were performed monthly only in T1 and T2, but visual clinical observations were made in all animals. Any group was treated with acaricide when the count’s average reached 50 or more ticks. It was necessary 7 baths with acaricide in T1 and T2, while in T3 group (control group it was necessary 19 acaricide baths to control the cattle tick. We verified

  20. Three Specialized Innovations for FAST Wideband Receiver

    Science.gov (United States)

    Zhang, Xia; Yu, Xinying; Duan, Ran; Hao, Jie; Li, Di

    2015-08-01

    The National Astronomical Observatories of the Chinese Academy of Sciences (NAOC) will soon finish the largest antenna in the world. Known as FAST, the Five-hundred-meter Aperture Spherical Radio Telescope will be the most sensitive single-dish radio telescope in the low frequency radio bands between 70 MHz and 3 GHz.To take advantage of its giant aperture, all relevant cutting-edge technology should be applied to FAST to ensure that it achieves the best possible overall performance. The wideband receiver that is currently under development can not only be directly applied to FAST, but also used for other Chinese radio telescopes, such as the Shanghai 65-meter telescope and the Xinjiang 110-meter telescope, to ensure that these telescopes are among the best in the world. Recently, rapid development related to this wideband receiver has been underway. In this paper, we will introduce three key aspects of the FAST wideband receiver project. First is the use of a high-performance analog-to-digital converter (ADC). With the cooperation of Hao Jie’s team from the Institute of Automation of the Chinese Academy of Sciences(CASIA), we have developed 3-Gsps,12-bit ADCs, which have not been used previously in astronomy, and we expect to realize the 3-GHz bandwidth in a single step by covering the entire bandwidth via interleaving or a complex fast Fourier transform (FFT).Second is the front-end analog signal integrated circuit board. We wish to achieve a series of amplification, attenuation, and mixing filtering operations on a single small board, thereby achieving digital control of the bandpass behavior both flexibly and highly-efficiently. This design will not only greatly reduce the required cost and power but will also make the best use of the digital-system’s flexibility. Third is optimization of the FFT: the existing FFT is not very efficient; therefore, we will optimize the FFT for large-scale operation. For this purpose, we intend to cascade two FFTs. Another

  1. Call Center Capacity Planning

    DEFF Research Database (Denmark)

    Nielsen, Thomas Bang

    in modern call centers allows for a high level of customization, but also induces complicated operational processes. The size of the industry together with the complex and labor intensive nature of large call centers motivates the research carried out to understand the underlying processes. The customizable...... groups are further analyzed. The design of the overflow policies is optimized using Markov Decision Processes and a gain with regard to service levels is obtained. Also, the fixed threshold policy is investigated and found to be appropriate when one class is given high priority and when it is desired...

  2. User Centered Design

    DEFF Research Database (Denmark)

    Egbert, Maria; Matthews, Ben

    2012-01-01

    The interdisciplinary approach of User Centered Design is presented here with a focus on innovation in the design and use of hearing technologies as well as on the potential of innovation in interaction. This approach is geared towards developing new products, systems, technologies and practices...... based on an understanding of why so few persons with hearing loss use the highly advanced hearing technologies. In integrating Conversation Analysis (“CA”), audiology and User Centered Design, three disciplines which are collaborating together for the first time, we are addressing the following...

  3. QUAD FAMILY CENTERING.

    Energy Technology Data Exchange (ETDEWEB)

    PINAYEV, I.

    2005-11-01

    It is well known that beam position monitors (BPM) utilizing signals from pickup electrodes (PUE) provide good resolution and relative accuracy. The absolute accuracy (i.e. position of the orbit in the vacuum chamber) is not very good due to the various reasons. To overcome the limitation it was suggested to use magnetic centers of quadrupoles for the calibration of the BPM [1]. The proposed method provides accuracy better then 200 microns for centering of the beam position monitors using modulation of the whole quadrupole family.

  4. Xichang Satellite Launch Center

    Institute of Scientific and Technical Information of China (English)

    LiuJie

    2004-01-01

    Xichang Satellite Launch Center(XSLC) is mainly for geosynchronous orbit launches. The main purpose of XSLC is to launch spacecraft, such as broadcasting,communications and meteorological satellites, into geo-stationary orbit.Most of the commercial satellite launches of Long March vehicles have been from Xichang Satellite Launch Center. With 20 years' development,XSLC can launch 5 kinds of launch vehicles and send satellites into geostationary orbit and polar orbit. In the future, moon exploration satellites will also be launched from XSLC.

  5. Data Center Energy Retrofits

    OpenAIRE

    PervilÀ, Mikko

    2013-01-01

    Within the field of computer science, data centers (DCs) are a major consumer of energy. A large part of that energy is used for cooling down the exhaust heat of the servers contained in the DCs. This thesis describes both the aggregate numbers of DCs and key flagship installations in detail. We then introduce the concept of Data Center Energy Retrofits, a set of low cost, easy to install techniques that may be used by the majority of DCs for reducing their energy consumption. The main c...

  6. Lied Transplant Center

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-02-01

    The Department of Energy has prepared an Environmental Assessment (DOE/EA-1143) evaluating the construction, equipping and operation of the proposed Lied Transplant Center at the University of Nebraska Medical Center in Omaha, Nebraska. Based on the analysis in the EA, the DOE has determined that the proposed action does not constitute a major federal action significantly affecting the quality of the human environment within the meaning of the National Environmental Policy Act of 1969 (NEPA). Therefore, the preparation of an Environmental Statement in not required.

  7. Patient-centered professionalism

    Directory of Open Access Journals (Sweden)

    Rapport F

    2012-03-01

    Full Text Available Hayley A Hutchings, Frances RapportCollege of Medicine, Swansea University, Swansea, Wales, United KingdomIntroduction: Although the concept of patient-centered professionalism has been defined in the literature and adopted to some extent by key health care regulatory bodies, there has been little research that has identified what the concept means to professionals and patients.Aim: The purpose of this paper is to identify the key concepts of patient-centered professionalism as identified in the literature and to discuss these within the context of existing research across a variety of health care settings.Findings: Key documents have been identified from within nursing, medicine, and pharmacy, which outline what is expected of professionals within these professional groups according to their working practices. Although not defined as patient-centered professionalism, the principles outlined in these documents mirror the definitions of patient-centered professional care defined by Irvine and the Picker Institute and are remarkably similar across the three professions. While patients are identified as being at the heart of health care and professional working practice, research within the fields of community nursing and community pharmacy suggests that patient and professional views diverge as regards what is important, according to different group agendas. In addition, the delivery of patient-centered professional care is often difficult to achieve, due to numerous challenges to the provision of patient-centric care.Conclusion: According to the literature, patient-centered professionalism means putting the patient at the heart of care delivery and working in partnership with the patient to ensure patients are well informed and their care choices are respected. However, limited research has examined what the concept means to patients and health care professionals working with patients and how this fits with literature definitions. Further work is

  8. Direct and Evolutionary Approaches for Optimal Receiver Function Inversion

    Science.gov (United States)

    Dugda, Mulugeta Tuji

    Receiver functions are time series obtained by deconvolving vertical component seismograms from radial component seismograms. Receiver functions represent the impulse response of the earth structure beneath a seismic station. Generally, receiver functions consist of a number of seismic phases related to discontinuities in the crust and upper mantle. The relative arrival times of these phases are correlated with the locations of discontinuities as well as the media of seismic wave propagation. The Moho (Mohorovicic discontinuity) is a major interface or discontinuity that separates the crust and the mantle. In this research, automatic techniques to determine the depth of the Moho from the earth's surface (the crustal thickness H) and the ratio of crustal seismic P-wave velocity (Vp) to S-wave velocity (Vs) (kappa= Vp/Vs) were developed. In this dissertation, an optimization problem of inverting receiver functions has been developed to determine crustal parameters and the three associated weights using evolutionary and direct optimization techniques. The first technique developed makes use of the evolutionary Genetic Algorithms (GA) optimization technique. The second technique developed combines the direct Generalized Pattern Search (GPS) and evolutionary Fitness Proportionate Niching (FPN) techniques by employing their strengths. In a previous study, Monte Carlo technique has been utilized for determining variable weights in the H-kappa stacking of receiver functions. Compared to that previously introduced variable weights approach, the current GA and GPS-FPN techniques have tremendous advantages of saving time and these new techniques are suitable for automatic and simultaneous determination of crustal parameters and appropriate weights. The GA implementation provides optimal or near optimal weights necessary in stacking receiver functions as well as optimal H and kappa values simultaneously. Generally, the objective function of the H-kappa stacking problem

  9. Signal Processing for Improved Wireless Receiver Performance

    DEFF Research Database (Denmark)

    Christensen, Lars P.B.

    2007-01-01

    This thesis is concerned with signal processing for improving the performance of wireless communication receivers for well-established cellular networks such as the GSM/EDGE and WCDMA/HSPA systems. The goal of doing so, is to improve the end-user experience and/or provide a higher system capacity...... in connection with parameter estimation. Next, a realistic framework for interference whitening is presented, allowing flexibility in the selection of whether interference is accounted for via a discrete or a Gaussian distribution. The approximate method of sphere detection and decoding is outlined and various...... suggestions for improvements are presented. In addition, methods for using generalized BP to perform approximate joint detection and decoding in systems with convolutional codes are outlined. One such method is a natural generalization of the traditional Turbo principle and a generalized Turbo principle can...

  10. The BINP receives its Golden Hadron award

    CERN Multimedia

    2002-01-01

    On Thursday, 14 September, the LHC Project Leader, Lyn Evans, handed over a Golden Hadron award to Alexander Skrinsky of Russia's Budker Institute of Nuclear Physics (BINP). The prize is awarded in recognition of exceptional performances by suppliers and this year prizes were awarded to two firms, Cockerill-Sambre (Belgium) and Wah-Chang (United States), and to the Budker Institute, which was unable to receive the award at the same time as the two other recipients (see Bulletin No 34/2002, of 19 August 2002). The Russian institute has been rewarded for the particularly high-quality production of 360 dipole magnets and 185 quadrupole magnets for the LHC proton beam transfer lines.

  11. Teleseismic receiver functions imaging of Siberia

    DEFF Research Database (Denmark)

    Soliman, Mohammad Youssof Ahmad; Thybo, Hans; Artemieva, Irina

    2014-01-01

    be used for determining Moho depth, and are excellent for detecting relatively broad vertical gradients in velocity, such as expected for a thermally controlled LAB. The combination of both types of RFs allows for independent discontinuity models of the same area in different frequency bands using......We map the lithosphere in Siberia by using the available broadband seismic data for calculation of Ps- and Sp-wave receiver functions (RF). RFs show converted waves from discontinuities in the vicinity of the seismic stations. The main objective is to image the Moho and upper mantle discontinuities......, including the lithosphere-asthenosphere boundary (LAB) beneath the study area. We construct the RF using the LQT method (Vinnik, 1977; Kind et al. 1995) in the version by Yuan et al. (1997). Rotation of ray coordinates uses the incidence angles predicted by the AK135 velocity model. This decomposes the wave...

  12. Jiang Zemin Receives New ACWF Leadership

    Institute of Scientific and Technical Information of China (English)

    1998-01-01

    FOUR days after the adjournment of the 8th Chinese Women’s National Congress, President Jiang Zemin received all the newly-elected members of the executive committee and several deputies at Zhongnanhai. Gu Xiulian, Vice President and the First Member of the Secretariat of the All-China Women’s Federation (ACWF), briefed Jiang on the congress. She said deputies had reached consensus on certain issues: that women should capitalize on their abilities in the overall social participation; that the uplifting of women’s quality should be seen as a long-term strategy; and that women’s development requires a supportive social environment. Jiang Zemin listened attentively to the speeches delivered by seven deputies. Jiang Daguo, president of Hubei Provincial Women’s Federation, from one of the

  13. Receiver based PAPR reduction in OFDMA

    KAUST Repository

    Ali, Anum Z.

    2014-05-01

    High peak-to-average power ratio is one of the major drawbacks of orthogonal frequency division multiplexing (OFDM). Clipping is the simplest peak reduction scheme, however, it requires clipping mitigation at the receiver. Recently compressed sensing has been used for clipping mitigation (by exploiting the sparse nature of clipping signal). However, clipping estimation in multi-user scenario (i.e., OFDMA) is not straightforward as clipping distortions overlap in frequency domain and one cannot distinguish between distortions from different users. In this work, a collaborative clipping removal strategy is proposed based on joint estimation of the clipping distortions from all users. Further, an effective data aided channel estimation strategy for clipped OFDM is also outlined. Simulation results are presented to justify the effectiveness of the proposed schemes. © 2014 IEEE.

  14. Humboldt SK pilot biodigester receives funding

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    2005-09-30

    The Canada-Saskatchewan Western Economic Partnership Agreement (WEPA) will provide funding for Canada's first pilot-scale biodigester to be built in Humboldt, Saskatchewan. The $208,138 pilot facility will use household garbage as well as agricultural waste such as manure and livestock operations, abattoirs and food processing to create heat or power and fertilizer. Support for this bio-energy facility, which could also reduce greenhouse gases, will come from the Prairie Agricultural Machinery Institute which has received $186,138 from Canada and Saskatchewan in the form of cost-shared federal-provincial funding. The pilot plant will test different combinations of waste material feedstocks and the characteristics of the resulting gas end products. The pilot facility will also provide design information for full-scale biodigester manufacturers in Canada. It is expected that 25 full-scale biodigesters will be constructed in Canada in the near future.

  15. Listeriosis in patients receiving biologic therapies.

    Science.gov (United States)

    Bodro, M; Paterson, D L

    2013-09-01

    The evolution of inflammatory diseases has radically changed since the introduction of biologic therapies, such as tumour necrosis factor alpha inhibitors (anti-TNFα). They, therefore, represent a widely used therapeutic modality. Nevertheless, post-marketing studies reveal an increased risk of infection in patients taking these drugs, especially granulomatous infections such as listeriosis. We aimed to evaluate the reported cases of listeriosis in patients treated with biologic treatments. We used the United States Food and Drug Administration (FDA) Adverse Event Reporting System (AERS) from 2004 to 2011. We also perform a literature review of previously reported cases of listeriosis in patients taking biologic therapies. We identified 266 cases of Listeria monocytogenes infection associated with biologic therapies. The majority of patients were receiving infliximab (77.1 %), followed by etanercept (11.7 %), adalimumab (9.8 %), rituximab (4.1 %), abatacept (0.4 %) and golimumab (0.4 %). Indications for the use of biologics were as follows: 47.7 % for rheumatologic diseases, 38 % for inflammatory bowel diseases, 3.4 % for haematological diseases and 10.5 % for other indications. Seventy-three percent of the patients were receiving concomitant immunosuppressant drugs, especially steroids (56 %) and methotrexate (31.6 %). The median time to the onset of infection was 184 days. Mortality rates range from 11.1 % in adalimumab-treated patients to 27.3 % in rituximab-treated patients (p = 0.7). Listeriosis is common in biologics-treated patients, especially related to infliximab use given concomitantly with other immunosuppressive therapies. Infections after treatment with biologics mostly occurred in the first year after initiating treatment.

  16. Ototoxicity in children receiving cisplatin chemotherapy

    Directory of Open Access Journals (Sweden)

    Hee Jin Jang

    2010-02-01

    Full Text Available Purpose : Cisplatin is highly effective for the treatment of solid tumors in children. However, the clinical use of cisplatin is limited by its ototoxicity. The aim of this study was to evaluate the ototoxicity in children treated with cisplatin. Methods : We performed a single institution retrospective analysis of pediatric oncology patients who received cisplatin therapy between January 2001 and January 2008. Thirty-seven patients with sufficient medical and audiologic data were included in this study. Results : The median age at the time of diagnosis was 10.7 (range 3.8&#8211;16.7 years. There were 16 males and 21 females. The underlying diseases were osteosarcoma (15 cases, medulloblastoma (14 cases, germ cell tumors (7 cases, and hepatoblastoma (1 case. The median individual dose was 100 mg/m2/cycle (56-200. The median cumulative dose was 480 mg/m2 (200-1,490. Sixteen patients (43% received cranial radiotherapy. Of the 37 patients, 17 developed hearing loss, leading to an overall incidence of 46%. Logistic regression showed that age at treatment (P=0.04 and cumulative dose of cisplatin (P=0.005 were the significant risk factors in predicting hearing loss in children treated with cisplatin. In all the patients who had hearing loss, there was neither improvement nor aggravation during the follow-up (3&#8211;68 months. Conclusion : The cumulative dose of cisplatin (&gt;500 mg/m2 and younger age at treatment (&lt;12 years were 2 most important risk factors for ototoxicity in patients treated with cisplatin. Serial audiometric evaluations are needed in the patients with risk factors during and after cisplatin treatment.

  17. Phase Noise Tolerant QPSK Receiver Using Phase Sensitive Wavelength Conversion

    DEFF Research Database (Denmark)

    Da Ros, Francesco; Xu, Jing; Lei, Lei

    2013-01-01

    A novel QPSK receiver based on a phase noise reduction pre-stage exploiting PSA in a HNLF and balanced detection is presented. Receiver sensitivity improvement over a conventional balanced receiver is demonstrated.......A novel QPSK receiver based on a phase noise reduction pre-stage exploiting PSA in a HNLF and balanced detection is presented. Receiver sensitivity improvement over a conventional balanced receiver is demonstrated....

  18. Center for Botanical Interaction Studies

    Data.gov (United States)

    Federal Laboratory Consortium — Research Area: Dietary Supplements, Herbs, Antioxidants Program:Centers for Dietary Supplements Research: Botanicals Description:This center will look at safety and...

  19. Data Analysis and Assessment Center

    Data.gov (United States)

    Federal Laboratory Consortium — The DoD Supercomputing Resource Center (DSRC) Data Analysis and Assessment Center (DAAC) provides classified facilities to enhance customer interactions with the ARL...

  20. Postmastectomy Radiotherapy for Locally Advanced Breast Cancer Receiving Neoadjuvant Chemotherapy

    Directory of Open Access Journals (Sweden)

    Icro Meattini

    2014-01-01

    Full Text Available Neoadjuvant chemotherapy (NAC is widely used in locally advanced breast cancer (BC treatment. The role of postmastectomy radiotherapy (PMRT after NAC is strongly debated. The aim of our analysis was to identify major prognostic factors in a single-center series, with emphasis on PMRT. From 1997 to 2011, 170 patients were treated with NAC and mastectomy at our center; 98 cases (57.6% underwent PMRT and 72 cases (42.4% did not receive radiation. At a median follow-up period of 7.7 years (range 2–16 for the whole cohort, median time to locoregional recurrence (LRR was 3.3 years (range 0.7–12.4. The 5-year and 10-year actuarial LRR rate were 14.5% and 15.9%, respectively. At the multivariate analysis the factors that significantly correlated with survival outcome were ≥4 positive nodes (HR 5.0, 1.51–16.52; P=0.035, extracapsular extension (HR 2.18, 1.37–3.46; P=0.009, and estrogen receptor positive disease (HR 0.57, 0.36–0.90; P=0.003. Concerning LRR according to use of radiation, PMRT reduced LRR for patient with clinical T3 staged disease (P=0.015. Our experience confirmed the impact of pathological nodal involvement on survival outcome. PMRT was found to improve local control in patients presenting with clinical T3 tumors, regardless of the response to chemotherapy.

  1. Predictors of insulin requirements among hospitalized adults receiving parenteral nutrition.

    Science.gov (United States)

    Roehl, Kelly A; Lach, Kristen; Coltman, Anne E; Bacon, Cheryl A; Singh, Shubha; Peterson, Sarah J; Sowa, Diane C

    2013-11-01

    The objective of this quality improvement project was to determine factors predictive of parenteral nutrition (PN) insulin therapy. Patients receiving PN at a tertiary care academic medical center between January 1, 2009, and December 1, 2012, 18 years or older were included. Variables collected included demographics, medical information, and PN-specific data. χ(2) and Student t tests were used to determine differences between patients who did and did not require PN insulin. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to determine associations between characteristics. Stepwise forward logistic regression was used determine the best predictors of PN insulin. A total of 1388 patients were started on PN. After adjusting for potential confounders, strong associations existed between PN insulin requirements and diabetes mellitus (DM) diagnosis (OR, 8.90; 95% CI, 4.98-15.90, P obese status (body mass index ≥25.0 kg/m(2)) (OR, 2.12; 95% CI, 1.04-4.30, P = .04), intensive care unit (ICU) admission (OR, 1.79; 95% CI, 1.03-3.11, P = .04), blood glucose (BG) on day of PN start >120 mg/dL (OR, 2.32; 95% CI, 1.32-4.05, P = .003), mean BG >180 mg/dL while receiving PN (OR, 6.10; 95% CI, 2.18-17.04, P = .001), and hemoglobin A1c (A1c) ≥5.7% (OR, 3.18; 95% CI, 1.84-5.50, P 120 mg/dL on PN start day (P < .001), and ICU admission (P < .001) predicted the need for PN insulin.

  2. Starting a sleep center.

    Science.gov (United States)

    Epstein, Lawrence J; Valentine, Paul S

    2010-05-01

    The demand for sleep medicine services has grown tremendously during the last decade and will likely continue. To date, growth in demand has been met by growth in the number of new sleep centers. The need for more new centers will be dependent on market drivers that include increasing regulatory requirements, personnel shortages, integration of home sleep testing, changes in reimbursement, a shift in emphasis from diagnostics to treatment, and an increased consumer focus on sleep. The decision to open a new center should be based on understanding the market dynamics, completing a market analysis, and developing a business plan. The business plan should include an overview of the facility, a personnel and organizational structure, an evaluation of the business environment, a financial plan, a description of services provided, and a strategy for obtaining, managing, and extending a referral base. Implementation of the business plan and successful operation require ongoing planning and monitoring of operational parameters. The need for new sleep centers will likely continue, but the shifting market dynamics indicate a greater need for understanding the marketplace and careful planning.

  3. Memorial Alexander Center

    Directory of Open Access Journals (Sweden)

    AECK Associates, Arquitectos

    1958-05-01

    Full Text Available En Atlanta, el Instituto Tecnológico de Georgia acaba de ampliar sus instalaciones deportivas, construyendo el Alexander Memorial Center. Consta este nuevo Centro de dos edificios: una pista de baloncesto cubierta y un edificio anejo con vestuarios, duchas, una pista de entrenamiento, equipos técnicos y la emisora de radio Georgia Tech W. G. S. T.

  4. School Based Health Centers

    Science.gov (United States)

    Children's Aid Society, 2012

    2012-01-01

    School Based Health Centers (SBHC) are considered by experts as one of the most effective and efficient ways to provide preventive health care to children. Few programs are as successful in delivering health care to children at no cost to the patient, and where they are: in school. For many underserved children, The Children's Aid Society's…

  5. vCenter troubleshooting

    CERN Document Server

    Mills, Chuck

    2015-01-01

    The book is designed for the competent vCenter administrator or anyone who is responsible for the vSphere environment. It can be used as a guide by vSphere architects and VMware consultants for a successful vSphere solution. You should have good knowledge and an understanding of core elements and applications of the vSphere environment.

  6. LCA Center Denmark

    DEFF Research Database (Denmark)

    Hauschild, Michael Zwicky; Frydendal, Jeppe

    2006-01-01

    product-oriented environmental tools in companies, to ensure that the LCA efforts is based on a solid and scientific basis, and to maintain the well-established co-operation between all important actors in the LCA field in Denmark. A status is given on the achievements of LCA Center Denmark...

  7. Carolinas Energy Career Center

    Energy Technology Data Exchange (ETDEWEB)

    Classens, Anver; Hooper, Dick; Johnson, Bruce

    2013-03-31

    Central Piedmont Community College (CPCC), located in Charlotte, North Carolina, established the Carolinas Energy Career Center (Center) - a comprehensive training entity to meet the dynamic needs of the Charlotte region's energy workforce. The Center provides training for high-demand careers in both conventional energy (fossil) and renewable energy (nuclear and solar technologies/energy efficiency). CPCC completed four tasks that will position the Center as a leading resource for energy career training in the Southeast: • Development and Pilot of a New Advanced Welding Curriculum, • Program Enhancement of Non-Destructive Examination (NDE) Technology, • Student Support through implementation of a model targeted toward Energy and STEM Careers to support student learning, • Project Management and Reporting. As a result of DOE funding support, CPCC achieved the following outcomes: • Increased capacity to serve and train students in emerging energy industry careers; • Developed new courses and curricula to support emerging energy industry careers; • Established new training/laboratory resources; • Generated a pool of highly qualified, technically skilled workers to support the growing energy industry sector.

  8. Data Center Site Redundancy

    OpenAIRE

    Brotherton, H M; Dietz, J. Eric

    2014-01-01

    Commonly, disaster contingency calls for separation of location for redundant locations to maintain the needed redundancy. This document addresses issues for the data center redundancy, including limits to the distribution, distance and location that may impact on the efficiency or energy.

  9. Alternative Fuels Data Center

    Energy Technology Data Exchange (ETDEWEB)

    None

    2013-06-01

    Fact sheet describes the Alternative Fuels Data Center, which provides information, data, and tools to help fleets and other transportation decision makers find ways to reduce petroleum consumption through the use of alternative and renewable fuels, advanced vehicles, and other fuel-saving measures.

  10. Resource Centers; Some Ideas.

    Science.gov (United States)

    Klitzke, Dwight Mark; Starkey, John

    Teachers, Principals, and other public school personnel interested in establishing learning resource centers are provided with guidelines and a framework within which they can structure their efforts. Professional literature, observation, and experimental trials serve as the sources from which observations are drawn. The advantages of the resource…

  11. Mobile PET Center Project

    Science.gov (United States)

    Ryzhikova, O.; Naumov, N.; Sergienko, V.; Kostylev, V.

    2017-01-01

    Positron emission tomography is the most promising technology to monitor cancer and heart disease treatment. Stationary PET center requires substantial financial resources and time for construction and equipping. The developed mobile solution will allow introducing PET technology quickly without major investments.

  12. User-Centered Design through Learner-Centered Instruction

    Science.gov (United States)

    Altay, Burçak

    2014-01-01

    This article initially demonstrates the parallels between the learner-centered approach in education and the user-centered approach in design disciplines. Afterward, a course on human factors that applies learner-centered methods to teach user-centered design is introduced. The focus is on three tasks to identify the application of theoretical and…

  13. Economics of data center optics

    Science.gov (United States)

    Huff, Lisa

    2016-03-01

    Traffic to and from data centers is now reaching Zettabytes/year. Even the smallest of businesses now rely on data centers for revenue generation. And, the largest data centers today are orders of magnitude larger than the supercomputing centers of a few years ago. Until quite recently, for most data center managers, optical data centers were nice to dream about, but not really essential. Today, the all-optical data center - perhaps even an all-single mode fiber (SMF) data center is something that even managers of medium-sized data centers should be considering. Economical transceivers are the key to increased adoption of data center optics. An analysis of current and near future data center optics economics will be discussed in this paper.

  14. Polypharmacy Treatment of Hypertensionin Public Health Centers

    Directory of Open Access Journals (Sweden)

    Vasanthi A/P Nayagam

    2016-12-01

    Full Text Available Background: Hypertension is one of the most prominent global diseases. Despite the availability of effective therapies, hypertension remains poorly controlled in Indonesia. In many cases, patient’s noncompliance may be attributable to the low patients’ knowledge, attitude, and life-style practices such as polypharmacy. Polypharmacy is defined as the administration of many drugs at in one prescription. Polypharmacy increases expenses, possible adverse reaction to a single agent, incidence of drug interactions, and decreases patient’s compliance This study aimed to identify the practice of polypharmacy in hypertension treatment in primary health centers. Methods: A cross-sectional descriptive observational study was carried out on 60 patients from two primary health centers in Jatinangor, West Java, Indonesia in October 2013. Sociodemographic profile, degree of hypertension, types of antihypertensive drugs, concomitant drugs given together with antihypertensive drugs, and treatment compliance data were collected and presented in tables and figures. Results: The incidence of hypertension was more common among male patients compared to female patients. Thirty-three patients (55% have low compliance to their medication. Twenty-nine patients (48% received single drug and 31 patients (52% received more than one drugs. Conclusions: The percentage of polypharmacy practice in treating hypertension in primary health centers is 52%. The most frequently prescribed anti-hypertensive are angiotensin-converting enzyme (ACE inhibitors and calcium-channel blockers (CCB. Most of hypertensive patients have low compliance to therapy.

  15. Acute hepatitis C in patients receiving hemodialysis.

    Science.gov (United States)

    Griveas, I; Germanidis, G; Visvardis, G; Morice, Y; Perelson, A S; Pawlotsky, J M; Papadopoulou, D

    2007-01-01

    Hepatitis C virus (HCV) infection is frequent in patients with end-stage renal disease treated by chronic dialysis, with a prevalence varying from 10-65% according to the geographical data. The prevalence is significantly associated with the duration of dialysis and the number of transfused blood products[1,2] and has dramatically declined with efficient blood screening.[3] We studied patients with acute HCV infection in a dialysis unit. The diagnosis was based on both anti-HCV detection and HCV-RNA detection. Other virological tools including HCV genotype determination was also used to tailor treatment to the individual patient and determine its efficacy for a one-year follow-up period. Seventeen patients (7 male and 10 female, mean age: 63.7 +/- 11.6 SD) with acute hepatitis C were enrolled to our study. All of them were followed up for a period of one year after the diagnosis was established. Phylogenetic analysis distinguished two separate HCV subtypes 1b, which were both responsible for this acute infection (see Figure 1). These types did not differ in their behavior on the clinical situation of our patients, as confirmed by the fact that in both groups of patients, there was only one patient who presented with acute illness. Six patients of our study group, three months after the acute infection, received pegylated interferon (Peg-IFNa2a) 135 mug for a six-month period. Four of them responded very well to therapy and at the first determination HCV RNA was below the cutoff point. One of our patients with very high HCV levels (HCV RNA > 50,000,000 IU/mL), despite receiving the same therapy, did not respond well and developed cirrhosis. In conclusion, it is clear from our experience that better information is needed about the current incidence, prevalence, and risk factors for HCV infection in dialysis patients. Algorithms for the diagnosis and management of hepatitis C should be developed by academic societies. Routine screening for hepatitis C also would allow

  16. Dish stirling solar receiver combustor test program

    Science.gov (United States)

    Bankston, C. P.; Back, L. H.

    1981-01-01

    The operational and energy transfer characteristics of the Dish Stirling Solar Receiver (DSSR) combustor/heat exchanger system was evaluated. The DSSR is designed to operate with fossil fuel augmentation utilizing a swirl combustor and cross flow heat exchanger consisting of a single row of 4 closely spaced tubes that are curved into a conical shape. The performance of the combustor/heat exchanger system without a Stirling engine was studied over a range of operating conditions and output levels using water as the working fluid. Results show that the combustor may be started under cold conditions, controlled safety, and operated at a constant air/fuel ratio (10 percent excess air) over the required range of firing rates. Furthermore, nondimensional heat transfer coefficients based on total heat transfer are plotted versus Reynolds number and compared with literature data taken for single rows of closely spaced tubes perpendicular to cross flow. The data show enhanced heat transfer for the present geometry and test conditions. Analysis of the results shows that the present system meets specified thermal requirements, thus verifying the feasibility of the DSSR combustor design for final prototype fabrication.

  17. CERN safety expert receives international award

    CERN Multimedia

    2005-01-01

    On 18 December 2004, the President of the Swiss Electro-technical Committee, Martin Reichle (left), presented the award to Helmut Schönbacher. Helmut Schönbacher, of the Safety Commission at CERN, has received, the "1906 Award" of the International Electrotechnical Commission (IEC) for his standardisation work on the influence of ionizing radiation on insulating materials. From 1986 until 2004, Schönbacher was leader of a working group on radiation composed of internationally recognised experts. It edited standards of the IEC 60544 series on the determination of the effects of ionizing radiation on electrical insulating materials. The working group also edited three IEC Technical Reports on the determination of long-term radiation ageing in polymers. This standardisation work and long-term experience from CERN on the radiation ageing of materials also contributed to research coordination programmes of the International Atomic Energy Agency (IAEA). From 1968 until 1988, Schönbacher was a member of the Rad...

  18. Social Interactions Receive Priority to Conscious Perception.

    Science.gov (United States)

    Su, Junzhu; van Boxtel, Jeroen J A; Lu, Hongjing

    2016-01-01

    Humans are social animals, constantly engaged with other people. The importance of social thought and action is hard to overstate. However, is social information so important that it actually determines which stimuli are promoted to conscious experience and which stimuli are suppressed as invisible? To address this question, we used a binocular rivalry paradigm, in which the two eyes receive different action stimuli. In two experiments we measured the conscious percept of rival actions and found that actions engaged in social interactions are granted preferential access to visual awareness over non-interactive actions. Lastly, an attentional task that presumably engaged the mentalizing system enhanced the priority assigned to social interactions in reaching conscious perception. We also found a positive correlation between human identification of interactive activity and the promotion of socially-relevant information to visual awareness. The present findings suggest that the visual system amplifies socially-relevant sensory information and actively promotes it to consciousness, thereby facilitating inferences about social interactions.

  19. Neufeld Receives 2009 Donald L. Turcotte Award

    Science.gov (United States)

    2010-03-01

    Jerome Neufeld has been awarded the Donald L. Turcotte Award, given annually to recent Ph.D. recipients for outstanding dissertation research that contributes directly to the field of nonlinear geophysics. Neufeld's thesis is entitled “Solidification in the fast lane: Flow-induced morphological instability in geological systems.” He was formally presented with the award at the Nonlinear Geophysics Focus Group reception during the 2009 AGU Fall Meeting, held 14-18 December in San Francisco, Calif. Jerome received his B.A.S. in engineering science from the University of Toronto in 2001, and a Ph.D. in geophysics from Yale University in 2008, under the supervision of J. S. Wettlaufer, on the impact of oceanic currents on the formation of sea ice. He is currently a fellow at the Institute of Theoretical Geophysics, University of Cambridge, working on the fluid dynamics of geophysical systems including carbon dioxide sequestration, the influence of flow on the crystal structure of mushy layers, and the evolution of icicles.

  20. Animal choruses emerge from receiver psychology

    Science.gov (United States)

    Greenfield, Michael D.; Esquer-Garrigos, Yareli; Streiff, Réjane; Party, Virginie

    2016-01-01

    Synchrony and alternation in large animal choruses are often viewed as adaptations by which cooperating males increase their attractiveness to females or evade predators. Alternatively, these seemingly composed productions may simply emerge by default from the receiver psychology of mate choice. This second, emergent property hypothesis has been inferred from findings that females in various acoustic species ignore male calls that follow a neighbor’s by a brief interval, that males often adjust the timing of their call rhythm and reduce the incidence of ineffective, following calls, and from simulations modeling the collective outcome of male adjustments. However, the purported connection between male song timing and female preference has never been tested experimentally, and the emergent property hypothesis has remained speculative. Studying a distinctive katydid species genetically structured as isolated populations, we conducted a comparative phylogenetic analysis of the correlation between male call timing and female preference. We report that across 17 sampled populations male adjustments match the interval over which females prefer leading calls; moreover, this correlation holds after correction for phylogenetic signal. Our study is the first demonstration that male adjustments coevolved with female preferences and thereby confirms the critical link in the emergent property model of chorus evolution. PMID:27670673

  1. Patrick Janot receives the CNRS silver medal

    CERN Multimedia

    2005-01-01

    Patrick Janot during the award ceremony. (Photo Schwemling, Paris) On 25 November, Patrick Janot of the CERN Physics Department received the CNRS silver medal for IN2P3 (Institut national de physique nucléaire et de physique des particules). This prize, one of the most prestigious awarded by the French research centre, is given to scientists for the 'originality, quality and importance of their work, as recognised both nationally and internationally'. Patrick Janot joined the ALEPH collaboration, one of the four experiments at LEP, then under construction, in 1987. First a CERN Fellow, he went on to work for the CNRS at LAL in 1989. Together with his team, he developed innovative algorithms for the reconstruction of events. This work and others earned him the bronze CNRS medal in 1993, which is awarded to scientists for their first achievements. In 1997, he became a permanent physicist at CERN, where he continued to work for ALEPH. He was appointed LEP scientific co-ordinator for the last two years of the ac...

  2. CERN Web Pages Receive a Makeover

    CERN Multimedia

    2001-01-01

    Asudden allergic reaction to the colour turquoise? Never fear, from Monday 2 April you'll be able to click in the pink box at the top of the CERN users' welcome page to go to the all-new welcome page, which is simpler and better organized. CERN's new-look intranet is the first step in a complete Web-makeover being applied by the Web Public Education (WPE) group of ETT Division. The transition will be progressive, to allow users to familiarize themselves with the new pages. Until 17 April, CERN users will still get the familiar turquoise welcome page by default, with the new pages operating in parallel. From then on, the default will switch to the new pages, with the old ones being finally switched off on 25 May. Some 400 pages have received the makeover treatment. For more information about the changes to your Web, take a look at: http://www.cern.ch/CERN/NewUserPages/ Happy surfing!

  3. PTSD: National Center for PTSD

    Medline Plus

    Full Text Available ... Clinics Vet Centers Regional Benefits Offices Regional Loan Centers Cemetery Locations Search Enter your search text Button to start ... Clinics Vet Centers Regional Benefits Offices Regional Loan Centers Cemetery Locations Contact Us FAQs Ask a Question Toll Free ...

  4. To center or not to center? Investigating inertia with a multilevel autoregressive model

    Directory of Open Access Journals (Sweden)

    Ellen L. Hamaker

    2015-01-01

    Full Text Available Whether level 1 predictors should be centered per cluster has received considerable attention in the multilevel literature. While most agree that there is no one preferred approach, it has also been argued that cluster mean centering is desirable when the within-cluster slope and the between-cluster slope are expected to deviate, and the main interest is in the within-cluster slope. However, we show in a series of simulations that if one has a multilevel autoregressive model in which the level 1 predictor is the lagged outcome variable (i.e., the outcome variable at the previous occasion, cluster mean centering will in general lead to a downward bias in the parameter estimate of the within-cluster slope (i.e., the autoregressive relationship. This is particularly relevant if the main question is whether there is on average an autoregressive effect. Nonetheless, we show that if the main interest is in estimating the effect of a level 2 predictor on the autoregressive parameter (i.e., a cross-level interaction, cluster mean centering should be preferred over other forms of centering. Hence, researchers should be clear on what is considered the main goal of their study, and base their choice of centering method on this when using a multilevel autoregressive model.

  5. 30 CFR 57.13011 - Air receiver tanks.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Air receiver tanks. 57.13011 Section 57.13011... Boilers § 57.13011 Air receiver tanks. Air receiver tanks shall be equipped with one or more automatic... exceeding the maximum allowable working pressure in a receiver tank by not more than 10 percent....

  6. 30 CFR 56.13011 - Air receiver tanks.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Air receiver tanks. 56.13011 Section 56.13011... § 56.13011 Air receiver tanks. Air receiver tanks shall be equipped with one or more automatic pressure... the maximum allowable working pressure in a receiver tank by not more than 10 percent. Air...

  7. 42 CFR 435.120 - Individuals receiving SSI.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 4 2010-10-01 2010-10-01 false Individuals receiving SSI. 435.120 Section 435.120..., Blind, and Disabled § 435.120 Individuals receiving SSI. Except as allowed under § 435.121, the agency... deemed to be receiving SSI. This includes individuals who are— (a) Receiving SSI pending a final...

  8. Entanglement with Centers

    CERN Document Server

    Ma, Chen-Te

    2015-01-01

    Entanglement is a physical phenomenon that each state cannot be described individually. Entanglement entropy gives quantitative understanding to the entanglement. We use decomposition of the Hilbert space to discuss properties of the entanglement. Therefore, partial trace operator becomes important to define the reduced density matrix from different centers, which commutes with all elements in the Hilbert space, corresponding to different entanglement choices or different observations on entangling surface. Entanglement entropy is expected to satisfy the strong subadditivity. We discuss decomposition of the Hilbert space for the strong subadditivity and other related inequalities. The entanglement entropy with centers can be computed from the Hamitonian formulations systematically, provided that we know wavefunctional. In the Hamitonian formulation, it is easier to obtain symmetry structure. We consider massless $p$-form theory as an example. The massless $p$-form theory in ($2p+2)$-dimensions has global symm...

  9. A Case of Recurrent Transient Monocular Visual Loss after Receiving Sildenafil

    Directory of Open Access Journals (Sweden)

    Asaad Ghanem Ghanem

    2011-01-01

    Full Text Available A 53-year-old man was attended to the Clinic Ophthalmic Center, Mansoura University, Egypt, with recurrent transient monocular visual loss after receiving sildenafil citrate (Viagra for erectile dysfunction. Examination for possible risk factors revealed mild hypercholesterolemia. Family history showed that his father had suffered from bilateral nonarteritic anterior ischemic optic neuropathy (NAION. Physicians might look for arteriosclerotic risk factors and family history of NAION among predisposing risk factors before prescribing sildenafil erectile dysfunction drugs.

  10. Differential stress responses among newly received calves: variations in reductant capacity and Hsp gene expression

    OpenAIRE

    Eitam, Harel; Vaya, Jacob; Brosh, Arieh; Orlov, Ala; Khatib, Soliman; Izhaki, Ido; Shabtay, Ariel

    2010-01-01

    Bovine respiratory disease complex (BRD), a major economic concern to the beef cattle industry all over the world, is triggered by physical, biological and psychological stresses. It is becoming noticeable that the key to reducing BRD appears to be centered at reducing the response to stress. The aims of the present study were to detect individual variations in the stress response of newly received young calves through their leukocyte heat shock protein (Hsp) response, selected neutrophil-rel...

  11. Simultaneous Transmit and Receive Performance of an 8-channel Digital Phased Array

    Science.gov (United States)

    2017-01-16

    Simultaneous Transmit and Receive Performance of an 8- channel Digital Phased Array Jonathan P. Doane, Kenneth E. Kolodziej, Bradley T. Perry MIT...traditional digital cancellation is typically limited by channel noise and distortion. A unique aspect of the ALSTAR digital canceller is the use of...elements, and an 8- channel digital transceiver chassis. width which is mixed to an IF center frequency of 187.5 MHz, supporting digital sampling in the

  12. COMPUTATIONAL SCIENCE CENTER

    Energy Technology Data Exchange (ETDEWEB)

    DAVENPORT,J.

    2004-11-01

    The Brookhaven Computational Science Center brings together researchers in biology, chemistry, physics, and medicine with applied mathematicians and computer scientists to exploit the remarkable opportunities for scientific discovery which have been enabled by modern computers. These opportunities are especially great in computational biology and nanoscience, but extend throughout science and technology and include for example, nuclear and high energy physics, astrophysics, materials and chemical science, sustainable energy, environment, and homeland security.

  13. NRH Neuroscience Research Center

    Science.gov (United States)

    2008-06-01

    PRESENTATIONS: INTERNATIONAL STUDIES Stroke Rehabilitation Practice in New Zealand and the U.S. (H McNaughton) The European CERISE Study (K Putman ) A...National Rehabilitation Hospital on September 8-9, 2007 • Our project team hosted, Koen Putman , PT, PhD, a Fulbright Scholar from the Free...University of Brussels. The Project team worked with Dr. Putman in merging his data from a 5-center (from 4 countries) stroke rehabilitation outcomes study

  14. Home media center

    OpenAIRE

    Valverde Martinez, Juan Miguel

    2014-01-01

    One of the most popular indoor entertainment systems nowadays is related to playing multimedia files, not only at home but also in public events such as watching movies in cinemas or playing music in nightclubs or pubs. Developers are responsible for making this easier and innovating in the development of these systems in different ways. This project's goal was to develop a home media center which allows the user to play multimedia files easily. In addition, the development was intended t...

  15. National Biocontainment Training Center

    Science.gov (United States)

    2016-10-01

    reporting period. Both BSL3 and BSL4 laboratories are housed in this new multi-story facility located on the University of Melbourne campus. The...BRL supports research programs in the National Center for Biodefense and Infectious Diseases, and the BRL is equipped with facilities to house ...Lower Rhine in The Netherlands. Doherty Institute – Melbourne , Australia – Miguel Grimaldo continues his consultations with the Peter Doherty

  16. Advanced Cancer Detection Center

    Science.gov (United States)

    2009-01-01

    Neurocognitive Deficits in Children who Received Cancer Treatment Affecting the Central Nervous System (HLMCC 0707) • Melatonin and sleep hygiene...Environmental Determinants of Diabetes in the Young. (PI: Jeffrey Krischer, Ph.D.) The aetiology of type 1 diabetes (T1D) remains unknown, however...progression to diabetes . To test these hypotheses, large groups of young children at risk for T1D must be followed prospectively with collection of

  17. Turcotte Receives 2003 William Bowie Medal

    Science.gov (United States)

    Cathles, Lawrence M.; Turcotte, Donald L.

    2004-01-01

    ``Few have contributed more to fundamental geophysics, or been better at encouraging others to contribute, than Donald L. Turcotte. Don trained as an engineer, receiving a Ph.D. in Aeronautics and Physics from the California Institute of Technology in 1958. After a year at the Naval Postgraduate School in Monterey, he joined the Cornell Graduate School of Aeronautical Engineering, rising to full professor. He established expertise on seeded combustion, magnetohydrodynamic and electrical phenomena in turbulent boundary layers, and shock waves and authored a book, Space Propulsion, and co-authored a textbook, Statistical Thermodynamics. ``In 1965 he went on sabbatical to Oxford and returned an Earth scientist. The catalyst was Ron Oxburgh. Plate tectonics was just on the horizon, and Don joined his quantitative abilities and physical intuition with Ron's skills and knowledge of geology to produce over the next decade a remarkable series of 24 papers that explored topics such as the many implications of the Earth's thermal boundary layer, ridge melting, subduction zone volcanism, and intraplate tectonics and magmatism, and established the physical bases for many of the processes operating on our planet. Shifting to the Cornell Department of Geological Sciences in 1973, Don explored virtually every aspect of physical Earth geology and became an expert on planetary remote sensing and geophysical interpretation. He published over 150 papers on thermal subsidence in sedimentary basins, two-phase hydrothermal porous media convection, lithosphere flexure, cyclic sedimentation, and stick-slip earthquakes and the lithospheres and mantles of the other planets. He worked and published with outstanding students and colleagues including Ken Torrance, Gerald Schubert, David Spence, Marc Parmentier, Bill Haxby, John Ockendon, Kevin Burke, Jud Ahern, Steve Emerman, and Charlie Angevine. In 1982 he published Geodynamics with Jerry Schubert, a book that became the primary reference in

  18. Hypocupremia in patients receiving total parenteral nutrition.

    Science.gov (United States)

    Bozzetti, F; Inglese, M G; Terno, G; Pupa, A; Sequeira, C; Migliavacca, S

    1983-01-01

    Although hypocupremia is a well-known consequence of long-term total parenteral nutrition (TPN), its incidence as well as the duration of TPN necessary to induce it are still unsettled. The purpose of this study is to review the changes in serum copper level in 25 patients receiving TPN for a period longer than 2 wk (mean duration 6 wk) at the Istituto Nazionale Tumori of Milan and to evaluate the possible relationship of cupremia with the basic disease. Main indications for TPN included enterocutaneous fistulas (11 patients), cancer cachexia (10 patients), radiation enteropathy (two patients), and severe postoperative stricture following esophagogastric resection (two patients). Mean value of serum copper at the beginning of the study was 143 micrograms/100 ml (normal value 65-165 micrograms/100 ml), and the regression analysis showed a mean fall of 5.64 micrograms/100 ml/wk. Hypocupremia occurred in four patients (three with intestinal fistulas and one with radiation obstructive enteritis) at 5th, 6th, 9th, and 6th wk of TPN, respectively. No patient with cancer cachexia developed hypocupremia. No patient with hypocupremia had clinical evidence of a copper deficiency syndrome. We conclude that 1) hypocupremia does not occur within the first month of TPN; 2) its incidence is about 16% in patients intravenously fed for period longer than 2 wk; 3) it is more frequent in patients with enterocutaneous fistulas, whereas it never occurs in patients with cancer cachexia, and 4) it is not necessarily associated to a clinicometabolic syndrome of copper deficiency. Finally, the "nutritional" meaning of serum copper should be questioned in cancer patients since it could represent a "tumor marker."

  19. 3-Receiver Broadcast Channels with Common and Confidential Messages

    CERN Document Server

    Chia, Yeow-Khiang

    2009-01-01

    Achievable secrecy rate regions for the general 3-receiver broadcast channel with one common and one confidential message sets are established. We consider two setups: (i) when the confidential message is to be sent to two of the receivers and the third receiver is an eavesdropper; and (ii) when the confidential message is to be sent to one of the receivers and the other two receivers are eavesdroppers. We show that our secrecy rate regions are optimum for some special cases.

  20. Precise Clock Solutions Using Carrier Phase from GPS Receivers in the International GPS Service

    Science.gov (United States)

    Zumberge, J. F.; Jefferson, D. C.; Stowers, D. A.; Tjoelker, R. L.; Young, L. E.

    1999-01-01

    As one of its activities as an Analysis Center in the International GPS Service (IGS), the Jet Propulsion Laboratory (JPL) uses data from a globally distributed network of geodetic-quality GPS receivers to estimate precise clock solutions, relative to a chosen reference, for both the GPS satellites and GPS receiver internal clocks, every day. The GPS constellation and ground network provide geometrical strength resulting in formal errors of about 100 p sec for these estimates. Some of the receivers in the global IGS network contain high quality frequency references, such as hydrogen masers. The clock solutions for such receivers are smooth at the 20-p sec level on time scales of a few minutes. There are occasional (daily to weekly) shifts at the microsec level, symptomatic of receiver resets, and 200-p sec-level discontinuities at midnight due to 1-day processing boundaries. Relative clock solutions among 22 IGS sites proposed as "fiducial" in the IGS/BIPM pilot project have been examined over a recent 4-week period. This allows a quantitative measure of receiver reset frequency as a function of site. For days and-sites without resets, the Allan deviation of the relative clock solutions is also computed for subdaily values of tau..