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Sample records for hemoglobinuria receiving eculizumab

  1. Pregnancy outcomes of patients with paroxysmal nocturnal hemoglobinuria treated with eculizumab: a Japanese experience and updated review.

    PubMed

    Miyasaka, Naoyuki; Miura, Osamu; Kawaguchi, Tatsuya; Arima, Nobuyoshi; Morishita, Eriko; Usuki, Kensuke; Morita, Yasuyoshi; Nishiwaki, Kaichi; Ninomiya, Haruhiko; Gotoh, Akihiko; Imashuku, Shinsaku; Urabe, Akio; Shichishima, Tsutomu; Nishimura, Jun-Ichi; Kanakura, Yuzuru

    2016-06-01

    Pregnancy with paroxysmal nocturnal hemoglobinuria (PNH) is associated with significant risk of complications, such as life-threatening thrombosis. Recently, eculizumab has come into clinical use and revolutionized the treatment of PNH. However, clinical information regarding eculizumab use for PNH during pregnancy is limited. The present report describes pregnancies with PNH treated with eculizumab that were registered with the Japan PNH study group and reviews the literature. In case 1, the patient received eculizumab throughout pregnancy and delivered a healthy neonate at term, although breakthrough hemolysis occurred at 20 weeks of gestation. In case 2, the patient discontinued eculizumab before pregnancy and developed preeclampsia at 27 weeks of gestation. She received eculizumab and delivered a preterm, but healthy, neonate by cesarean section. In case 3, the patient received eculizumab from 18 weeks of gestation and delivered a healthy neonate at term without any complications. Reports of 11 pregnant women treated with eculizumab were identified in the literature. Of 14 pregnancies, including our own cases, breakthrough hemolysis and preeclampsia occurred in five and two cases, respectively. There were no thrombotic complications, maternal or neonatal deaths, or fetal structural abnormalities. Thus, eculizumab appears to be safe and effective for managing PNH during pregnancy.

  2. Eculizumab in Pregnant Patients with Paroxysmal Nocturnal Hemoglobinuria.

    PubMed

    Kelly, Richard J; Höchsmann, Britta; Szer, Jeff; Kulasekararaj, Austin; de Guibert, Sophie; Röth, Alexander; Weitz, Ilene C; Armstrong, Elina; Risitano, Antonio M; Patriquin, Christopher J; Terriou, Louis; Muus, Petra; Hill, Anita; Turner, Michelle P; Schrezenmeier, Hubert; Peffault de Latour, Regis

    2015-09-10

    Eculizumab, a humanized monoclonal antibody against complement protein C5 that inhibits terminal complement activation, has been shown to prevent complications of paroxysmal nocturnal hemoglobinuria (PNH) and improve quality of life and overall survival, but data on the use of eculizumab in women during pregnancy are scarce. We designed a questionnaire to solicit data on pregnancies in women with PNH and sent it to the members of the International PNH Interest Group and to the physicians participating in the International PNH Registry. We assessed the safety and efficacy of eculizumab in pregnant patients with PNH by examining the birth and developmental records of the children born and adverse events in the mothers. Of the 94 questionnaires that were sent out, 75 were returned, representing a response rate of 80%. Data on 75 pregnancies in 61 women with PNH were evaluated. There were no maternal deaths and three fetal deaths (4%). Six miscarriages (8%) occurred during the first trimester. Requirements for transfusion of red cells increased during pregnancy, from a mean of 0.14 units per month in the 6 months before pregnancy to 0.92 units per month during pregnancy. Platelet transfusions were given in 16 pregnancies. In 54% of pregnancies that progressed past the first trimester, the dose or the frequency of use of eculizumab had to be increased. Low-molecular-weight heparin was used in 88% of the pregnancies. Ten hemorrhagic events and 2 thrombotic events were documented; both thrombotic events occurred during the postpartum period. A total of 22 births (29%) were premature. Twenty cord-blood samples were examined for the presence of eculizumab; the drug was detected in 7 of the samples. A total of 25 babies were breast-fed, and in 10 of these cases, breast milk was examined for the presence of eculizumab; the drug was not detected in any of the 10 breast-milk samples. Eculizumab provided benefit for women with PNH during pregnancy, as evidenced by a high rate of

  3. Atypical presentation of paroxysmal nocturnal hemoglobinuria treated by eculizumab

    PubMed Central

    Quinquenel, Anne; Maestraggi, Quentin; Lecoq-Lafon, Carinne; Régis, Peffault de Latour; Delmer, Alain; Servettaz, Amélie

    2017-01-01

    Abstract Rationale: Paroxysmal nocturnal hemoglobinuria (PNH) is a nonmalignant acquired hematopoietic stem cell disease, which can be revealed by hemolytic anemia, thromboembolism, or bonemarrow failure. Thrombosis can occur at any site, but coronary thrombosis is extremely rare. Controlled trials have demonstrated that eculizimab, an inhibitor of the terminal complement cascade, was able to reduce both hemolysis and thrombosis, but its efficacy in cases of PNH with coronary thrombosis is unknown. Patient concerns and diagnoses: We report herein the unusual case of a 73-year-old patient presenting with recurrent coronary syndromes without associated stenosis, fever, marked inflammatory syndrome, and anemia, leading to a delayed diagnosis of PNH. Intervention and outcomes: Eculizumab allowed the resolution of fever and inflammation, and prevented further thromboembolism. Lessons: This case emphasizes the importance of performing aflow cytometry test for PNH in front of unusual or unexplained recurrent thromboses. Thromboses, as observed in our case, may be associated with fever and marked inflammation. This case also provides useful information on eculizumab ability to prevent further thromboembolism in PNH patients with a medical history of arterial thrombosis. PMID:28328837

  4. Extravascular hemolysis and complement consumption in Paroxysmal Nocturnal Hemoglobinuria patients undergoing eculizumab treatment.

    PubMed

    Subías Hidalgo, Marta; Martin Merinero, Hector; López, Alicia; Anter, Jaouad; García, Sheila Pinto; Ataúlfo Gonzalez-Fernández, Fernando; Forés, Rafael; Lopez-Trascasa, Margarita; Villegas, Ana; Ojeda, Emilio; Rodríguez de Córdoba, Santiago

    2017-02-01

    Paroxysmal nocturnal hemoglobinuria (PNH) is an acquired hemolytic anemia characterized by complement-mediated intravascular hemolysis that is effectively treated with eculizumab. However, treatment responses are reported heterogeneous with some patients presenting residual hemolysis and requiring RBC transfusions. Recent reports have shown that both extravascular hemolysis and incomplete C5 blockade can explain these suboptimal hematological responses. Here we have tested our eculizumab-treated PNH patients (n=12) for signs of hemolysis and assessed complement biomarkers. Patients were also genotyped for complement receptor 1 (CR1, CD35) and C5 polymorphisms and evaluated for free eculizumab in plasma. We report that 10 patients (83%) present parameters suggesting persistent hemolysis, although they did not require additional transfusions. Seven of them (58%) become direct Coombs-test positive as a consequence of treatment, including all patients carrying the low-expression CR1-L allele. CH50 and sC5b-9 assays demonstrate that the persistent low-level hemolysis identified in our treated patients is not a consequence of incomplete C5 blockade, supporting that this hemolysis, as has been suggested previously, results from the extravascular removal of C3 opsonized PNH erythrocytes. We also show that continuous alternative pathway activation in eculizumab-treated individuals carrying the CR1-L allele results in abnormally decreased levels of C3 in plasma that could, potentially, increase their susceptibility to bacterial infections. Finally, we encourage a routine evaluation of free eculizumab levels and terminal pathway activity to personalize eculizumab administration.

  5. Interim analysis of post-marketing surveillance of eculizumab for paroxysmal nocturnal hemoglobinuria in Japan.

    PubMed

    Ninomiya, Haruhiko; Obara, Naoshi; Chiba, Shigeru; Usuki, Kensuke; Nishiwaki, Kaichi; Matsumura, Itaru; Shichishima, Tsutomu; Okamoto, Shinichiro; Nishimura, Jun-Ichi; Ohyashiki, Kazuma; Nakao, Shinji; Ando, Kiyoshi; Kanda, Yoshinobu; Kawaguchi, Tatsuya; Nakakuma, Hideki; Harada, Daisuke; Akiyama, Hirozumi; Kinoshita, Taroh; Ozawa, Keiya; Omine, Mitsuhiro; Kanakura, Yuzuru

    2016-11-01

    Data characterizing the safety and effectiveness of eculizumab in patients with paroxysmal nocturnal hemoglobinuria (PNH) are limited. We describe the safety and effectiveness of eculizumab in PNH patients enrolled in a post-marketing surveillance study. Types and frequencies of observed adverse events were similar to those reported in previous clinical trials and no meningococcal infection was reported. Effectiveness outcomes included the reduction of intravascular hemolysis, the change in hemoglobin (Hb) level, the withdrawal of transfusion and corticosteroids, the change of renal function, and overall survival. The effect of eculizumab on intravascular hemolysis was demonstrated by a reduction in lactate dehydrogenase levels at all measurements after baseline. Significant increases in Hb levels from baseline were also observed after 1 month's treatment with eculizumab (p < 0.01). Of those who were transfusion-dependent at baseline, the median number of transfusions decreased significantly from 18 to 0 unit/year after 1 year of treatment with eculizumab (p < 0.001). An increase in Hb and a high rate of transfusion independence were observed, especially in patients with platelet count ≥150 × 10(9)/L. Approximately 97 % of patients showed maintenance or improvement of renal function. Overall survival rate was about 90 % (median follow-up 1.9 years). These results suggest an acceptable safety profile and favorable prognosis after eculizumab intervention.

  6. Eculizumab in paroxysmal nocturnal hemoglobinuria with Budd-Chiari syndrome progressing despite anticoagulation

    PubMed Central

    2012-01-01

    Paroxysmal nocturnal hemoglobinuria (PNH) is a progressive, life-threatening disorder characterized by chronic intravascular hemolysis caused by uncontrolled complement activation. Hepatic vein thrombosis (Budd-Chiari syndrome) is common in PNH patients. This case report describes the response to eculizumab (a humanized monoclonal antibody that inhibits terminal complement activation) in a 25-year-old male with progressive liver function deterioration despite standard anticoagulation therapy and transjugular intrahepatic porto-systemic shunt. The patient presented with anemia, severe thrombocytopenia, headache, abdominal pain, and distention. He was diagnosed with PNH, cerebral vein thrombosis, and Budd-Chiari syndrome. Despite adequate anticoagulation, diuretic administration, and placement of a transjugular shunt, additional thrombotic events and progressive liver damage were observed. Eculizumab therapy was initiated, resulting in rapid blockade of intravascular hemolysis, increased platelet counts, ascites resolution, and liver function recovery, all of which are presently sustained. Since starting eculizumab the patient has had no further thrombotic events and his quality of life has dramatically improved. This is the first report to confirm the role of complement-mediated injury in the progression of Budd-Chiari syndrome in a patient with PNH. This case shows that terminal complement blockade with eculizumab can reverse progressive thromboses and hepatic failure that is unresponsive to anticoagulation therapy and suggests that early initiation of eculizumab should be included in the therapeutic regimen of patients with PNH-related Budd-Chiari syndrome. PMID:23210433

  7. Eculizumab in the management of paroxysmal nocturnal hemoglobinuria: patient selection and special considerations

    PubMed Central

    Al-Ani, Fatimah; Chin-Yee, Ian; Lazo-Langner, Alejandro

    2016-01-01

    Paroxysmal nocturnal hemoglobinuria (PNH) is a nonmalignant clonal disorder resulting from somatic mutation in the PIG-A gene leading to a deficiency of the membrane-anchoring molecule glycosylphosphatidylinositol. The lack of expression of two glycosylphosphatidylinositol-anchored proteins involved in the regulation of the complement system renders PNH erythrocytes susceptible to complement-mediated lysis. Clinical manifestations include thromboembolic disease, chronic kidney injury, pulmonary hypertension, smooth muscle dysfunction, and chronic hemolysis. Until recently, treatment was mainly supportive with most patients suffering from significant morbidity and shortened survival compared to age-matched controls. The development of eculizumab, a humanized monoclonal antibody directed against the terminal complement protein C5, has resulted in dramatic improvements of survival and reduction in complications. In this paper, we review some special considerations pertaining to the use of eculizumab for PNH. PMID:27536121

  8. Efficacy and safety of eculizumab in children and adolescents with paroxysmal nocturnal hemoglobinuria.

    PubMed

    Reiss, Ulrike M; Schwartz, Jeffrey; Sakamoto, Kathleen M; Puthenveetil, Geetha; Ogawa, Masayo; Bedrosian, Camille L; Ware, Russell E

    2014-09-01

    Paroxysmal nocturnal hemoglobinuria (PNH) is rare in children, but represents a similarly serious and chronic condition as in adults. Children with PNH frequently experience complications of chronic hemolysis, recurrent thrombosis, marrow failure, serious infections, abdominal pain, chronic fatigue, and decreased quality of life with reduced survival. The terminal complement inhibitor eculizumab is proven to be effective and safe in adults and approved by the FDA for treatment of PNH. This 12-week, open-label, multi-center phase I/II study evaluated pharmacokinetics, pharmacodynamics, efficacy, and safety in seven children with PNH 11-17 years of age. Eculizumab was intravenously administered at 600 mg weekly for 4 weeks, 900 mg in week 5, and 900 mg every 2 weeks thereafter (http://clinicaltrials.gov NCT00867932). Eculizumab therapy resulted in complete and sustained inhibition of hemolysis in all participants with a reduction of lactate dehydrogenase to normal levels. All hematological parameters stabilized. No definitive, study drug-related adverse events were observed. Only one severe SAE of hospitalization due to aplastic anemia occurred, which was not study drug-related. Eculizumab appears to be a safe and effective therapy for children with PNH. © 2014 Wiley Periodicals, Inc.

  9. Eculizumab Injection

    MedlinePlus

    Eculizumab injection is used to treat paroxysmal nocturnal hemoglobinuria (PNH: a type of anemia in which too many red ... oxygen to all parts of the body). Eculizumab injection is also used to treat atypical hemolytic uremic ...

  10. Successful management of obstructive jaundice due to gallstones with eculizumab in a patient with paroxysmal nocturnal hemoglobinuria.

    PubMed

    Kawano, Hiroki; Minagawa, Kentaro; Wakahashi, Kanako; Kawano, Yuko; Sada, Akiko; Matsui, Toshimitsu; Hirano, Hirotaka; Shiomi, Hideyuki; Ku, Yonson; Katayama, Yoshio

    2012-01-01

    Paroxysmal nocturnal hemoglobinuria (PNH) makes patients susceptible to intravascular hemolysis and thrombosis, and it can be life-threatening in stressful situations. Eculizumab, a humanized monoclonal antibody that inhibits the complement protein C5, has been evaluated as a novel therapy for PNH. We herein describe the case of a 59-year-old Japanese woman with classic PNH, who had been successfully treated with eculizumab, but who later developed acute cholecystitis/cholangitis from gallstones. Although the severe obstructive jaundice requiring endoscopic therapy following cholecystectomy was complicated, critical intravascular hemolysis and thrombosis were not observed. Therefore, utilizing eculizumab during the peri-operative management of PNH patients should be carefully taken into consideration.

  11. Serologic response to meningococcal vaccination in patients with paroxysmal nocturnal hemoglobinuria (PNH) chronically treated with the terminal complement inhibitor eculizumab.

    PubMed

    Alashkar, Ferras; Vance, Colin; Herich-Terhürne, Dörte; Preising, Nicole; Dührsen, Ulrich; Röth, Alexander

    2017-04-01

    Eculizumab is indicated for the therapy of patients with symptomatic paroxysmal nocturnal hemoglobinuria (PNH). Due to inhibition of terminal complement cascade, patients on eculizumab are susceptible to Neisseria meningitidis infections. The two mainstays to reduce the risk of infection are vaccination and antibiotic prophylaxis. In this retrospective study, serologic response was analyzed after vaccination with a meningococcal vaccine in 23 PNH patients (median age 36 years; range 25 - 88 years; 15 males, 8 females) by measuring serum bactericidal assay (SBA) using rabbit complement (rSBA) titers against meningococcal serogroups A, C, W, and Y. Serologic protection was defined by an rSBA titer ≥1:8. Forty-three percent (10/23) were vaccinated more than once due to chronic eculizumab treatment. Overall serologic response for the meningococcal serogroups was A: 78% (18/23), C: 87% (20/23), W: 48% (11/23), and Y: 70% (16/23). No meningococcal infections have been observed. As immunological response to vaccines varies, the use of serologic response analyses is warranted. Re-vaccination with a tetravalent conjugate vaccine under eculizumab therapy every 3 years is essential or should be based on response rates. If meningococcal infection is suspected, standby therapy with ciprofloxacin and immediate medical evaluation are recommended. The novel vaccines covering serogroup B may even further reduce the risk for infection.

  12. Positive Impact of Eculizumab Therapy on Surgery for Budd-Chiari Syndrome in a Patient with Paroxysmal Nocturnal Hemoglobinuria and a Long-Term History of Thrombosis

    PubMed Central

    De-la-Iglesia, Silvia; Luzardo, Hugo; Lemes, Angelina; Torres, Melissa; Gómez-Casares, Maria Teresa; Cruz, Naylen; Molero, Teresa

    2016-01-01

    Paroxysmal nocturnal hemoglobinuria (PNH) is associated with severe end-organ damage and a high risk of thrombosis. Budd-Chiari syndrome, which develops after thrombotic occlusion of major hepatic blood vessels, is relatively common in PNH and has been associated with increased mortality. We report the case of a 46-year-old male with PNH who presented with Budd-Chiari syndrome associated with portal cavernoma, portal hypertension and hypersplenism. In September 2010, the patient suffered gastrointestinal bleeding, hematuria, and elevated plasma lactate dehydrogenase; he started eculizumab therapy with a good response. In October 2012, he developed upper gastrointestinal variceal bleeding and a splenorenal shunt was placed. At the time of writing, the patient remains stable and eculizumab continues to be effective. There is limited data on the use of eculizumab for prevention of hemolysis and its consequences in PNH patients undergoing surgery. Our findings provide evidence for the efficacy and safety of eculizumab in this setting. PMID:27757214

  13. Hemoglobinuria test

    MedlinePlus

    ... PA: Elsevier Saunders; 2011:chap 28. Read More Acute nephritic syndrome Burns Hemolytic anemia Hemolytic-uremic syndrome Malaria Paroxysmal nocturnal hemoglobinuria (PNH) Pulmonary tuberculosis Renal cell carcinoma Sickle cell anemia Thalassemia Transfusion reaction - ...

  14. Hemoglobinuria after fraternity hazing.

    PubMed

    Baker, B A; Schwartz, K A; Segan, D J; Mayor, G H

    1982-09-01

    We describe a 19-year-old male who presented with traumatic hemoglobinuria. We hypothesize that this patient has a genetic haptoglobin variant with a low hemoglobin binding capacity which resulted in hemoglobinuria after physical fraternity hazing. A review of the literature regarding traumatic hemoglobinuria supports the association between decreased baseline plasma haptoglobin levels and hemoglobinuria after trauma.

  15. Multidisciplinary clinical management of paroxysmal nocturnal hemoglobinuria

    PubMed Central

    Sahin, Fahri; Ozkan, Melda Comert; Mete, Nihal Gokmen; Yilmaz, Mumtaz; Oruc, Nevin; Gurgun, Alev; Kayikcioglu, Meral; Guler, Ayse; Gokcay, Figen; Bilgir, Ferda; Ceylan, Cengiz; Bilgir, Oktay; Sari, Ismail Hakan; Saydam, Guray

    2015-01-01

    Paroxysmal nocturnal hemoglobinuria (PNH) is a rare, acquired disease caused by clonal expansion of one or more hematopoietic stem cell (HSC) lines due to a somatic mutation of the phosphatidylinositol glycan anchor (PIG-A) gene located on Xp22.1. PNH incidence is 1.5-2 cases per million of the population per year. PNH can affect multiple systems in the body and requires multidisciplinary clinical management. Patients can manifest with severe pancytopenia, life-threatening thrombosis affecting the hepatic, abdominal, cerebral, and subdermal veins, and high requirements for blood transfusion due to haemolytic anemia. PNH can also be associated with bone marrow failure. Advances in diagnostic techniques and a targeted therapeutic approach for PNH have emerged in the last two decades. Eculizumab, a promising humanized monoclonal antibody against C5, is the first approved therapy for PNH. PMID:26171279

  16. Cost-effectiveness of eculizumab treatment after kidney transplantation in patients with atypical haemolytic uraemic syndrome.

    PubMed

    van den Brand, Jan A J G; Verhave, Jacobien C; Adang, Eddy M; Wetzels, Jack F M

    2017-01-01

    Kidney transplantation in patients with atypical haemolytic uraemic syndrome (aHUS) is frequently complicated by recurrence of aHUS, often resulting in graft loss. Eculizumab prophylaxis prevents recurrence, improving graft survival. An alternative treatment strategy has been proposed where eculizumab is administered upon recurrence. We combined available evidence and performed a cost-effectiveness analysis of these competing strategies. A cost-effectiveness analysis using a decision analytical approach with Markov chain analyses was used to compare alternatives for aHUS patients with end-stage renal disease (ESRD): (i) dialysis treatment, (ii) kidney transplantation, (iii) kidney transplantation with eculizumab therapy upon recurrence of aHUS, (iv) kidney transplantation with eculizumab induction consisting of 12 months of prophylaxis and (v) kidney transplantation with lifelong eculizumab prophylaxis. We assumed that all patients received a graft from a living donor and that recurrence probability was 28.4% within the first year of transplantation. At 8.34 quality-adjusted life years (QALYs) gained and a cost of €402 412, kidney transplantation without eculizumab was the least costly alternative. By comparison, dialysis was more costly and resulted in fewer QALYs gained. Eculizumab upon recurrence resulted in 9.55 QALYs gained at a cost of €425 097. The incremental cost-effectiveness ratio (ICER) was €18 748 per QALY. Both eculizumab induction and lifelong eculizumab were inferior to eculizumab upon recurrence, as both resulted in fewer QALYs gained and higher costs. Kidney transplantation is more cost effective than dialysis to treat ESRD due to aHUS. Adding eculizumab treatment results in a substantial gain in QALYs. When compared with eculizumab upon recurrence, neither eculizumab induction nor lifelong eculizumab prophylaxis resulted in more QALYs, but did yield far higher costs. Therefore, eculizumab upon recurrence of aHUS is more acceptable.

  17. Anti-Complement Treatment in Paroxysmal Nocturnal Hemoglobinuria: Where we Stand and Where we are Going

    PubMed Central

    Risitano, Antonio M

    2014-01-01

    Paroxysmal nocturnal hemoglobinuria (PNH) is a clonal, non-malignant, hematological disorder characterized by the expansion of hematopoietic stem cells and progeny mature blood cells which are deficient in some surface proteins, including the two complement regulators CD55 and CD59. PNH is the paradigm of diseases implying complement dysregulation as main pathogenic mechanism; in fact, PNH erythrocytes are uncapable to modulate on their surface physiologic complement activation, which eventually leads to the typical clinical hallmark of PNH – the chronic complement-mediated intravascular anemia. Indeed, due to the lack of CD55 complement is continuously activated on erythrocyte surface, which subsequently enables the terminal lytic complement because of the lack of CD59, finally resulting in erythrocyte lysis. The availability of eculizumab as the first complement inhibitor for clinical use renewed the interest for this rare hematological disease. Indeed, in the last decad the anti-C5 monoclonal antibody has proven effective for the treatment of PNH, resulting in a sustained control of complement-mediated intravascular hemolysis, with a remarkable clinical benefit. Anti-complement treatment allowed transfusion independence in at least half of PNH patients receiving eculizumab, with adequate control of all hemolysis-associated symptoms even in almost all remaining patients. In addition, the risk of thromboembolic events – an other clinical hallmark of PNH, which significantly affects prognosis and survival – seems substantially reduced on eculizumab treatment, apparently resulting in improved survival. Even with all these remarkable effects, eculizumab treatment does not result in hemoglobin normalization, and most patients remain anemic. It has been demonstrated that this is due to persistent activation of the early phases of complement activation (upstream the C5), leading to complement-mediated extravascular hemolysis. Ongoing researches are focusing on

  18. Stratification of responders towards eculizumab using a structural epitope mapping strategy

    PubMed Central

    Volk, Anna-Luisa; Hu, Francis Jingxin; Berglund, Magnus M.; Nordling, Erik; Strömberg, Patrik; Uhlen, Mathias; Rockberg, Johan

    2016-01-01

    The complement component 5 (C5)-binding antibody eculizumab is used to treat patients with paroxysmal nocturnal hemoglobinuria (PNH) and atypical haemolytic uremic syndrome (aHUS). As recently reported there is a need for a precise classification of eculizumab responsive patients to allow for a safe and cost-effective treatment. To allow for such stratification, knowledge of the precise binding site of the drug on its target is crucial. Using a structural epitope mapping strategy based on bacterial surface display, flow cytometric sorting and validation via haemolytic activity testing, we identified six residues essential for binding of eculizumab to C5. This epitope co-localizes with the contact area recently identified by crystallography and includes positions in C5 mutated in non-responders. The identified epitope also includes residue W917, which is unique for human C5 and explains the observed lack of cross-reactivity for eculizumab with other primates. We could demonstrate that Ornithodorus moubata complement inhibitor (OmCI), in contrast to eculizumab, maintained anti-haemolytic function for mutations in any of the six epitope residues, thus representing a possible alternative treatment for patients non-responsive to eculizumab. The method for stratification of patients described here allows for precision medicine and should be applicable to several other diseases and therapeutics. PMID:27509843

  19. Small-molecule factor D inhibitors selectively block the alternative pathway of complement in paroxysmal nocturnal hemoglobinuria and atypical hemolytic uremic syndrome.

    PubMed

    Yuan, Xuan; Gavriilaki, Eleni; Thanassi, Jane A; Yang, Guangwei; Baines, Andrea C; Podos, Steven D; Huang, Yongqing; Huang, Mingjun; Brodsky, Robert A

    2017-03-01

    Paroxysmal nocturnal hemoglobinuria and atypical hemolytic uremic syndrome are diseases of excess activation of the alternative pathway of complement that are treated with eculizumab, a humanized monoclonal antibody against the terminal complement component C5. Eculizumab must be administered intravenously, and moreover some patients with paroxysmal nocturnal hemoglobinuria on eculizumab have symptomatic extravascular hemolysis, indicating an unmet need for additional therapeutic approaches. We report the activity of two novel small-molecule inhibitors of the alternative pathway component Factor D using in vitro correlates of both paroxysmal nocturnal hemoglobinuria and atypical hemolytic uremic syndrome. Both compounds bind human Factor D with high affinity and effectively inhibit its proteolytic activity against purified Factor B in complex with C3b. When tested using the traditional Ham test with cells from paroxysmal nocturnal hemoglobinuria patients, the Factor D inhibitors significantly reduced complement-mediated hemolysis at concentrations as low as 0.01 μM. Additionally the compound ACH-4471 significantly decreased C3 fragment deposition on paroxysmal nocturnal hemoglobinuria erythrocytes, indicating a reduced potential relative to eculizumab for extravascular hemolysis. Using the recently described modified Ham test with serum from patients with atypical hemolytic uremic syndrome, the compounds reduced the alternative pathway-mediated killing of PIGA-null reagent cells, thus establishing their potential utility for this disease of alternative pathway of complement dysregulation and validating the modified Ham test as a system for pre-clinical drug development for atypical hemolytic uremic syndrome. Finally, ACH-4471 blocked alternative pathway activity when administered orally to cynomolgus monkeys. In conclusion, the small-molecule Factor D inhibitors show potential as oral therapeutics for human diseases driven by the alternative pathway of complement

  20. Pathophysiology, diagnosis, and treatment of paroxysmal nocturnal hemoglobinuria: a review.

    PubMed

    Devalet, Bérangère; Mullier, François; Chatelain, Bernard; Dogné, Jean-Michel; Chatelain, Christian

    2015-09-01

    Paroxysmal nocturnal hemoglobinuria (PNH) is an acquired disorder of the hematopoietic stem cell that makes blood cells more sensitive to the action of complement. Patients experience intravascular hemolysis, smooth muscle dystonia, renal failure, arterial and pulmonary hypertension, recurrent infectious diseases and an increased risk of notably dreadful thrombotic complications. The diagnosis is made by flow cytometry. Efforts have been recently performed to improve the sensitivity and the standardization of this technique. PNH is frequently associated with aplastic anemia or low-risk myelodysplasia and may be asymptomatic. Management of the classical form of PNH has been dramatically revolutionized by the development of eculizumab, which brings benefits in terms of hemolysis, quality of life, renal function, thrombotic risk, and life expectancy. Prophylaxis and treatment of arterial and venous thrombosis currently remain a challenge in PNH.

  1. Paroxysmal cold hemoglobinuria.

    PubMed

    Shanbhag, Satish; Spivak, Jerry

    2015-06-01

    Paroxysmal cold hemoglobinuria is a rare cause of autoimmune hemolytic anemia predominantly seen as an acute form in young children after viral illnesses and in a chronic form in some hematological malignancies and tertiary syphilis. It is a complement mediated intravascular hemolytic anemia associated with a biphasic antibody against the P antigen on red cells. The antibody attaches to red cells at colder temperatures and causes red cell lysis when blood recirculates to warmer parts of the body. Treatment is mainly supportive and with red cell transfusion, but immunosuppressive therapy may be effective in severe cases. Copyright © 2015 Elsevier Inc. All rights reserved.

  2. Eculizumab treatment: stochastic occurrence of C3 binding to individual PNH erythrocytes.

    PubMed

    Sica, Michela; Rondelli, Tommaso; Ricci, Patrizia; De Angioletti, Maria; Risitano, Antonio M; Notaro, Rosario

    2017-06-19

    C5 blockade by eculizumab prevents complement-mediated intravascular hemolysis in paroxysmal nocturnal hemoglobinuria (PNH). However, C3-bound PNH red blood cells (RBCs), arising in almost all treated patients, may undergo extravascular hemolysis reducing clinical benefits. Despite the uniform deficiency of CD55 and of CD59, there are always two distinct populations of PNH RBCs, with (C3+) and without (C3-) C3 binding. To investigate this paradox, the phenomenon has been modeled in vitro by incubating RBCs from eculizumab untreated PNH patients with compatible sera containing eculizumab, and by assessing the C3 binding after activation of complement alternative pathway. When RBCs from untreated patients were exposed in vitro to activated complement in the context of C5-blockade, there was the prompt appearance of a distinct C3+ PNH RBC population whose size increased with time and also with the rate of complement activation. Eventually, all PNH RBCs become C3+ to the same extent, without differences between old and young (reticulocytes) PNH RBCs. This study indicates that the distinct (C3+ and C3-) PNH RBC populations are not intrinsically different; rather, they result from a stochastic all-or-nothing phenomenon linked to the time-dependent cumulative probability of each individual PNH red cell to be exposed to levels of complement activation able to trigger C3 binding. These findings may envision novel approaches to reduce C3 opsonization and the subsequent extravascular hemolysis in PNH patients on eculizumab.

  3. Postpartum thrombotic complication in a patient with paroxysmal nocturnal hemoglobinuria.

    PubMed

    Gessoni, Gianluca; Canistro, Rosa; Bergamini, Luca; Valverde, Sara; Gessoni, Francesca; Nani, Giovanna; Beggio, Samanta; Spillare, Pietro; Tregnaghi, Alberto

    2015-06-01

    Paroxysmal nocturnal hemoglobinuria (PNH) is a clonal nonneoplastic hematopoietic stem cell disease characterized by an acquired mutation of the PIG-A gene with reduction or absence of CD55 and CD59. The absence of these proteins renders PNH erythrocytes susceptible to complement-mediated hemolysis. We report the case of a PNH patient before and during pregnancy until delivery. We observed and treated some postpartum thrombotic complications. Eculizumab should be used with caution in pregnancy. There are several reports supporting its use in these patients. This case should be considered paradigmatic of a series of clinical situations that may occur in the course of a pregnancy in patients with PNH: increased need for transfusion, need to increase the dose of Eculizumab, and insurgence of fetal sufferance. Moreover, after delivery, the patient, despite adequate prophylaxis with low-molecular-weight heparins, presented severe complications: development of pleural and peritoneal effusion, pulmonary embolism, bilateral upper limbs thrombophlebitis, and a possible abdominal angina with a transient paralytic ileus. All these complications were overcome and now the baby is healthy and the mother has returned to the usual therapeutic regimen.

  4. Variable eculizumab clearance requires pharmacodynamic monitoring to optimize therapy for thrombotic microangiopathy after hematopoietic stem cell transplantation

    PubMed Central

    Jodele, Sonata; Fukuda, Tsuyoshi; Mizuno, Kana; Vinks, Alexander A.; Laskin, Benjamin L.; Goebel, Jens; Dixon, Bradley P.; Chima, Ranjit S; Hirsch, Russel; Teusink, Ashley; Lazear, Danielle; Lane, Adam; Myers, Kasiani C.; Dandoy, Christopher E.; Davies, Stella M.

    2015-01-01

    Thrombotic microangiopathy (TMA) after hematopoietic stem cell transplant (HSCT) associated with terminal complement activation, as measured by elevated plasma terminal complement (sC5b-9) concentrations, has a very high mortality. The complement inhibitor eculizumab may be a therapeutic option for HSCT-associated TMA. We examined the pharmacokinetics and pharmacodynamics (PK/PD) of eculizumab in children and young adult HSCT recipients with TMA and activated complement to determine drug dosing requirements for future efficacy trials. We analyzed prospectively collected laboratory samples and clinical data from 18 HSCT recipients with high-risk TMA presenting with complement activation who were treated with eculizumab. We measured eculizumab serum concentrations, total hemolytic complement activity (CH50), and plasma sC5b-9 concentrations. Population PK/PD analyses correlated eculizumab concentrations with complement blockade and clinical response and determined inter-individual differences in PK parameters. We also compared transplant survival in patients treated with eculizumab (n=18) to patients with the same high-risk TMA features who did not receive any targeted therapy during a separate prospective observational study (n=11). In the PK analysis, we found significant inter-patient variability in eculizumab clearance, ranging from 16 to 237 mL/hr/70kg in the induction phase. The degree of complement activation measured by sC5b-9 concentrations at the start of therapy, in addition to actual body weight, were significant determinants of eculizumab clearance and disease response. Sixty one percent of treated patients had complete resolution of TMA and were able to safely discontinue eculizumab without disease recurrence. Overall survival was significantly higher in treated subjects compared to untreated patients (56% versus 9%, p=0.003). Complement blocking therapy is associated with improved survival in HSCT patients with high-risk TMA who historically have

  5. Cerebral Venous Thrombosis in Paroxysmal Nocturnal Hemoglobinuria

    PubMed Central

    Meppiel, Elodie; Crassard, Isabelle; de Latour, Régis Peffault; de Guibert, Sophie; Terriou, Louis; Chabriat, Hugues; Socié, Gérard; Bousser, Marie-Germaine

    2015-01-01

    Abstract Paroxysmal nocturnal hemoglobinuria (PNH) is a rare acquired disorder of hematopoietic stem cells characterized by hemolytic anemia, marrow failure, and a high incidence of life-threatening venous thrombosis. Cerebral venous system is the second most frequent location of thrombosis after hepatic veins. However, data about PNH-related cerebral venous thrombosis (CVT) are very scarce because of the rarity of both the disorders. We report a French study about PNH patients with CVT. Patients were recruited retrospectively, from the Société Française d’Hématologie (SFH) registry of 465 patients with PNH; the Lariboisière registry of 399 patients with CVT; and a direct contact with 26 French Hematology Units. We review cases reported since 1938 in the English and French language literature. We then compared patients of our series with cases from the literature, with non-PNH-related CVT cases from Lariboisière registry, and with PNH patients without CVT from SFH registry. Fifteen patients were included between 1990 and 2012. Most patients were women (12/15) and half of them presented associated hormonal venous thrombosis risk factors. Three patients had concomitant hepatic vein thrombosis. CVT was the first manifestation of PNH in 4 patients. No major difference in CVT characteristics was found compared with non-PNH-related CVT cases, except for a younger age at diagnosis in PNH patients (P < 0.001). All patients were treated with anticoagulation therapy. One death occurred in acute stage. All surviving patients were independent 1 year after. Median survival time was 9 years. Recurrent thrombosis rate was 50% at 6 years, occurring in patients that did not have bone marrow transplantation or eculizumab therapy. Cases of death were mainly related to hepatic vein thrombosis. Prognosis of CVT was good in our series. However, these patients have a poor long-term prognosis due to PNH disease by itself. PNH treatment should be proposed as soon as possible to

  6. Discontinuation of dialysis with eculizumab therapy in a pediatric patient with dense deposit disease.

    PubMed

    Tran, Cheryl L; Sethi, Sanjeev; Murray, David; Cramer, Carl H; Sas, David J; Willrich, Maria; Smith, Richard J; Fervenza, Fernando C

    2016-04-01

    Dense deposit disease (DDD) is a rare glomerular disease caused by an uncontrolled activation of the alternative complement pathway leading to end-stage renal disease in 50 % of patients. As such, DDD has been classified within the spectrum of complement component 3 (C3) glomerulopathies due to its pathogenesis from alternative pathway dysregulation. Conventional immunosuppressive therapies have no proven effectiveness. Eculizumab, a terminal complement inhibitor, has been reported to mitigate disease in some cases. We report on the efficacy of eculizumab in a pediatric patient who failed to respond to cyclophosphamide, corticosteroids, and plasma exchange. Complement biomarker profiling was remarkable for low serum C3, low properdin, and elevated soluble C5b-9. Consistent with these findings, the alternative pathway functional assay was abnormally low, indicative of alternative pathway activity, although neither C3-nephritic factors nor Factor H autoantibodies were detected. Eculizumab therapy was associated with significant improvement in proteinuria and renal function allowing discontinuation of hemodialysis (HD). Repeat C3 and soluble C5b-9 levels normalized, showing that terminal complement pathway activity was successfully blocked while the patient was receiving eculizumab therapy. Repeat testing for alternative pathway activation allowed for a successful decrease in eculizumab dosing. The case reported here demonstrates the successful recovery of renal function in a pediatric patient on HD following the use of eculizumab.

  7. Notes from the Field: Meningococcal Disease in an International Traveler on Eculizumab Therapy - United States, 2015.

    PubMed

    Applegate, Allen O; Fong, Vanessa C; Tardivel, Kara; Lippold, Susan A; Zarate, Sheilah

    2016-07-15

    On June 2, 2015, CDC was notified that a male airline passenger, aged 41 years, with a fever of 105.4°F, headache, nausea, photophobia, diarrhea, and vomiting, which began approximately 3 hours after departure, was arriving to San Francisco, California, on a flight from Frankfurt, Germany. His symptoms reportedly started with neck stiffness 1 day earlier. Upon arrival, the patient was immediately transported to a local hospital, where he was in septic shock, which was followed by multisystem organ failure. Cerebrospinal fluid, obtained approximately 12 hours after initiation of treatment, was Gram stain- and culture-negative. Blood cultures, which were drawn before antibiotic treatment, were positive for Neisseria meningitides of indeterminate serogroup. A review of the patient's medical records revealed a history of paroxysmal nocturnal hemoglobinuria and current biweekly eculizumab (Soliris) therapy.

  8. Paroxysmal nocturnal hemoglobinuria: a single Spanish center’s experience over the last 40 yr

    PubMed Central

    Muñoz-Linares, Cristina; Ojeda, Emilio; Forés, Rafael; Pastrana, Miguel; Cabero, Martín; Morillo, Daniel; Bautista, Guiomar; Baños, Isolina; Monteserín, Carmen; Bravo, Pilar; Jaro, Esther; Cedena, Teresa; Steegmann, Juan Luis; Villegas, Ana; Cabrera, José Rafael

    2014-01-01

    Paroxysmal nocturnal hemoglobinuria (PNH) is a rare clonal disease. To date, many reviews and series have been described. We report the experience of our center by presenting a review of 56 PNH patient cases with an average age at diagnosis of 38 yr and follow-ups beginning at approximately 40 yr; the median survival rate was 11 yr. The average clonal size upon diagnosis was 48%, presenting a variable evolution. Thrombotic episodes and cancer were five each, and the main causes of death among our patients were equal at 8.9%. Radiological study by magnetic resonance imaging is presented as a fundamental technique for estimating the deposit of iron levels in the liver and kidney, as well as in some decisive cases at the start of eculizumab therapy. Sixteen patients have been treated with eculizumab so far in our series, and being a safe drug, it provides improvement in the patients’ quality of life, and the disappearance of clinical symptoms, and avoids the emergence of new thrombosis. PMID:24758317

  9. Compatible Transfusion Therapy for Paroxysmal Cold Hemoglobinuria

    ERIC Educational Resources Information Center

    Rausen, Aaron R.; And Others

    1975-01-01

    Presented are case histories of two children, ages 2 and 4 years, with paroxysmal cold hemoglobinuria (PCH, a syndrome characterized by acute intravascular hemoglobin dissolution and hemoglobin in the urine). (Author/CL)

  10. Compatible Transfusion Therapy for Paroxysmal Cold Hemoglobinuria

    ERIC Educational Resources Information Center

    Rausen, Aaron R.; And Others

    1975-01-01

    Presented are case histories of two children, ages 2 and 4 years, with paroxysmal cold hemoglobinuria (PCH, a syndrome characterized by acute intravascular hemoglobin dissolution and hemoglobin in the urine). (Author/CL)

  11. Effect on mother and child of eculizumab given before caesarean section in a patient with severe antiphospholipid syndrome

    PubMed Central

    Gustavsen, Alice; Skattum, Lillemor; Bergseth, Grethe; Lorentzen, Bjorg; Floisand, Yngvar; Bosnes, Vidar; Mollnes, Tom Eirik; Barratt-Due, Andreas

    2017-01-01

    Abstract Rationale: Antiphospholipid syndrome (APS) in pregnancy may trigger the life-threatening catastrophic antiphospholipid syndrome (CAPS). Complement activation is implicated in the pathogenesis, and inhibition of complement factor C5 is suggested as an additional treatment option. Patient concerns, diagnosis and interventions: We present a pregnant patient treated with the C5-inhibitor eculizumab due to high risk of developing devastating APS-related complications. The complement inhibitory effects of the treatment were examined both in the patient and the premature infant. Outcomes: Complement activity in the mother recovered considerably faster than anticipated; however, no new thrombosis or CAPS developed during the last week of pregnancy or postpartum. Blood sampling from the umbilical vein and artery, and from the infant after delivery showed low complement activity; however, only 0.3% of the eculizumab concentration detected in the mother, consistent with low placental passage of eculizumab. Lessons: The data underscore the importance of close monitoring of complement inhibition and individualizing dosage regimens in pregnant patients receiving eculizumab. We document how traditional functional complement activity tests cannot assess the effect of eculizumab in premature infants due to the very low levels of complement factors detected in this infant born in gestational week 33. Only trace amounts of eculizumab passed the placenta. In conclusion, complement C5 inhibition might be a safe candidate treatment option for APS during pregnancy and delivery, and additionally, enables prolongation of pregnancy with important weeks. PMID:28296762

  12. Eculizumab to treat antibody-mediated rejection in a 7-year-old kidney transplant recipient.

    PubMed

    Chehade, Hassib; Rotman, Samuel; Matter, Maurice; Girardin, Eric; Aubert, Vincent; Pascual, Manuel

    2015-02-01

    We report on successful early eculizumab administration to treat acute antibody-mediated rejection (ABMR) in a highly sensitized kidney transplant recipient. The recipient is a 7-year-old boy who received, 6 months after a desensitization protocol with monthly intravenous immunoglobulin infusion, a second kidney transplant in the presence of low donor-specific antibodies (DSAs). Both pretransplant lymphocytotoxic and flow cytometric crossmatch were negative. Allograft function recovered promptly, with excellent initial function. On postoperative day (POD) 4, the child developed significant proteinuria with an acute rise in serum creatinine. Allograft biopsy showed severe acute ABMR. Intravenous eculizumab (600 mg), preceded by a single session of plasmapheresis, was administered on POD 5 and 12 along with a 4-day thymoglobulin course. After the first dose of eculizumab, a strikingly rapid normalization of allograft function with a decrease in proteinuria occurred. However, because circulating DSA levels remained elevated, the child received 3 doses of intravenous immunoglobulin (POD 15, 16, and 17), with a significant subsequent decrease in DSA levels. At 9 months after transplant, the child continues to maintain excellent allograft function with undetectable circulating DSA levels. This unique case highlights the potential efficacy of using early eculizumab to rapidly reverse severe ABMR in pediatric transplantation, and therefore it suggests a novel therapeutic approach to treat acute ABMR.

  13. Pathogenesis of paroxysmal nocturnal hemoglobinuria.

    PubMed

    Murakami, Yoshiko

    Paroxysmal nocturnal hemoglobinuria (PNH) is an acquired GPI deficiency caused by somatic mutation of the PIGA gene in one or several hematopoietic stem cells. Recently, PNH caused by somatic mutation of one allele of the PIGT gene in combination with a germline mutation of the other allele was reported, showing that PIGA is not the only gene responsible for PNH, though other causes are rare. These mutant cells become GPI deficient, expand clonally and differentiate into all of the hematopoietic lineages. When GPI deficient erythrocytes increase in proportion, massive hemolysis occurs due to activated complement attack during infection. As the complement regulatory proteins such as CD59 and DAF are GPI anchored proteins, they are defective on GPI deficient erythrocytes and these abnormal erythrocytes are thereby left unprotected from complement attack. Hemolytic anemia, venous thrombosis, and bone marrow failure are thus the resulting triad of symptoms. Clonal expansion does not occur with PIGA deficiency alone. We hypothesize that PIGA deficient cells acquire a proliferative phenotype via additional gene mutations within the associated environment of bone marrow failure. This hypothesis will be explained by introducing recent reports.

  14. Systemic Complement Inhibition with Eculizumab for Geographic Atrophy in Age-Related Macular Degeneration

    PubMed Central

    Yehoshua, Zohar; Filho, Carlos Alexandre de Amorim Garcia; Nunes, Renata Portella; Gregori, Giovanni; Penha, Fernando M.; Moshfeghi, Andrew A.; Zhang, Kang; Sadda, SriniVas; Feuer, William; Rosenfeld, Philip J.

    2014-01-01

    Purpose To evaluate the effect of eculizumab, a systemic inhibitor of complement component (C5), on the growth of geographic atrophy (GA) in patients with age-related macular degeneration (AMD). Design Prospective, double-masked, randomized clinical trial. Participants Patients with GA measuring from 1.25 to 18 mm2 based on spectral-domain optical coherence tomography imaging. Methods Patients were randomized 2:1 to receive intravenous eculizumab or placebo over 6 months. In the eculizumab treatment arm, the first 10 patients received a low-dose regimen of 600 mg weekly for 4 weeks followed by 900 mg every 2 weeks until week 24, and the next 10 patients received a high-dose regimen of 900 mg weekly for 4 weeks followed by 1200 mg every 2 weeks until week 24. The placebo group was infused with saline. Patients were observed off treatment for an additional 26 weeks. Both normal-luminance and lowluminance visual acuities were measured throughout the study, and the low-luminance deficits were calculated as the difference between the letter scores. Main Outcome Measures Change in area of GA at 26 weeks. Results Thirty eyes of 30 patients were enrolled. Eighteen fellow eyes also met inclusion criteria and were analyzed as a secondary endpoint. For the 30 study eyes, mean square root of GA area measurements ± standard deviation at baseline were 2.55±0.94 and 2.02±0.74 mm in the eculizumab and placebo groups,respectively (P = 0.13). At 26 weeks, GA enlarged by a mean of 0.19±0.12 and 0.18±0.15 mm in the eculizumab and placebo groups, respectively (P = 0.96). At 52 weeks of follow-up, GA enlarged by a mean of 0.37±0.22 mm in the eculizumab-treated eyes and by a mean of 0.37±0.21 mm in the placebo group (P = 0.93, 2 sample t test). None of the eyes converted to wet AMD. No drug-related adverse events were identified. Conclusions Systemic complement inhibition with eculizumab was well tolerated through 6 months but did not decrease the growth rate of GA significantly

  15. Eculizumab in neonatal hemolytic uremic syndrome with homozygous factor H deficiency.

    PubMed

    Michaux, Katell; Bacchetta, Justine; Javouhey, Etienne; Cochat, Pierre; Frémaux-Bacchi, Véronique; Sellier-Leclerc, Anne-Laure

    2014-12-01

    Neonatal atypical hemolytic uremic syndrome (aHUS) is a rare but severe disease that is mainly due to methylmalonic aciduria or genetic complement abnormalities. Traditional management of aHUS includes plasma infusion/exchange, but in small or unstable infants, plasma exchange can be challenging because of high extracorporeal volume and difficulty to obtain an adequate venous access. The C5 complement blocker eculizumab has become a cornerstone of first-line management of aHUS due to complement deregulation in older patients. However, little data are available on its use in neonatal aHUS. We report on an 11-day-old neonate with severe aHUS (myocardial impairment, respiratory failure, acute kidney disease requiring hemodiafiltration) due to homozygous factor-H deficiency. She received early treatment with eculizumab as first-line therapy and completely recovered within 5 days. A second dose of eculizumab was administered 7 days after the first infusion, followed by a dose every 2 weeks for 2 months and then every 3 weeks, at the same dosage (300 mg). With more than 24 months of follow-up, renal function remains normal. We report on the long-term efficacy and safety of eculizumab as first-line therapy in neonatal aHUS. However its use still requires optimization in terms of indications and administration (frequency, dosage).

  16. A Hispanic female patient with heartburn: A rare presentation of Paroxysmal Nocturnal Hemoglobinuria.

    PubMed

    Figueroa-Jiménez, Luis A; González-Márquez, Amy Lee; Alicea-Guevara, Ricardo; Santiago-Casiano, Mónica; de la Paz-López, Maryknoll; Negrón-Garcia, Luis; Báez-Diaz, Luis; Cáceres-Pérkins, William

    2015-01-01

    Paroxysmal nocturnal hemoglobinuria (PNH) is a non-malignant, acquired clonal hematopoietic stem cell disease that can present with bone marrow failure, hemolytic anemia, smooth muscle dystonias, and thrombosis. We present a case of a 32 year-old-female, G2P2A0 with no past medical history of any systemic illnesses who refers approximately 2 months of progressively worsening constant heartburn with associated abdominal discomfort. CBC showed leukopenia (WBC 2.9 x 103 /µL) with neutropenia (segmented neutrophils 48%), macrocytic anemia (Hgb 6.1 g/dL, hematocrit 20%, MCV,113 fL) and thrombocytopenia (platelet count 59 x 109/L). Abdomino-pelvic CT scan revealed a superior mesenterc vein thrombosis, which was treated initially with low-molecular-weight heparih for full anticoagulation. Peripheral blood flow cytometry assays revealed diminished expression of CD55 and CD59 on the erythrocytes, granulocytes and monocytes.' Paroxysmal nocturnal hemoglobinuria is a rare, clonal, hematopoietic stem-cell disorder whose manifestations are almost entirely explained by complement-mediated intravascular hemolysis. The natural history of PNH is highly variable, ranging from indolent to life-threatening. The median survival is 10 to 15 years, but with a wide range. Thrombosis is the leading cause of death, but others may die of complications of bone marrow failure, renal failure, myelodysplastic syndrome, and leukemia. Anticoagulation is only partially effective in preventing thrombosis in PNH; thus, thrombosis is an absolute indication for initiating treatment with Eculizumab. Nevertheless, bone marrow transplantation (BMT) is still the only curative therapy for PNH but is associated with significant morbidity and mortality.

  17. A Hispanic female patient with heartburn: A rare presentation of Paroxysmal Nocturnal Hemoglobinuria

    PubMed Central

    Figueroa-Jiménez, Luis A.; González-Márquez, Amy Lee; Alicea-Guevara, Ricardo; Santiago-Casiano, Mόnica; de la Paz-López, Maryknoll; Negrón-Garcia, Luis; Báez-Dίaz, Luis; Cáceres-Pérkins, William

    2017-01-01

    Paroxysmal nocturnal hemoglobinuria (PNH) is a non-malignant, acquired clonal hematopoietic stem cell disease that can present with bone marrow failure, hemolytic anemia, smooth muscle dystonias, and thrombosis. We present a case of a 32 year-old-female, G2P2A0 with no past medical history of any systemic illnesses who refers approximately 2 months of progressively worsening constant heartburn with associated abdominal discomfort. CBC showed leukopenia (WBC 2.9 × 103 /μL) with neutropenia (segmented neutrophils 48%), macrocytic anemia (Hgb 6.1 g/dL, hematocrit 20%, MCV 113 fL) and thrombocytopenia (platelet count 59 × 109/L). Abdomino-pelvic CT scan revealed a superior mesenteric vein thrombosis, which was treated initially with low-molecular-weight heparin for full anticoagulation. Peripheral blood flow cytometry assays revealed diminished expression of CD55 and CD59 on the erythrocytes, granulocytes and monocytes. Paroxysmal nocturnal hemoglobinuria is a rare, clonal, hematopoietic stem-cell disorder whose manifestations are almost entirely explained by complement-mediated intravascular hemolysis. The natural history of PNH is highly variable, ranging from indolent to life-threatening. The median survival is 10 to 15 years, but with a wide range. Thrombosis is the leading cause of death, but others may die of complications of bone marrow failure, renal failure, myelodysplastic syndrome, and leukemia. Anticoagulation is only partially effective in preventing thrombosis in PNH; thus, thrombosis is an absolute indication for initiating treatment with Eculizumab. Nevertheless, bone marrow transplantation (BMT) is still the only curative therapy for PNH but is associated with significant morbidity and mortality. PMID:26742189

  18. Rituximab fails where eculizumab restores renal function in C3nef-related DDD.

    PubMed

    Rousset-Rouvière, Caroline; Cailliez, Mathilde; Garaix, Florentine; Bruno, Daniele; Laurent, Daniel; Tsimaratos, Michel

    2014-06-01

    Dense deposit disease (DDD), a C3 glomerulopathy (C3G), is a rare disease with unfavorable progression towards end-stage kidney disease. The pathogenesis of DDD is due to cytotoxic effects related to acquired or genetic dysregulation of the complement alternative pathway, which is at times accompanied by the production of C3 nephritic factor (C3NeF), an auto-antibody directed against the alternative C3 convertase. Available treatments include plasma exchange, CD20-targeted antibodies, and a terminal complement blockade via the anti-C5 monoclonal antibody eculizumab. We report here the case of an 8-year-old child with C3NeF and refractory DDD who presented with a nephritic syndrome. She tested positive for C3NeF activity; C3 was undetectable. Genetic analyses of the alternative complement pathway were normal. Methylprednisolone pulses and mycophenolate mofetil treatment resulted in complete recovery of renal function and a reduction in proteinuria. Corticosteroids were tapered and then withdrawn. Four months after corticosteroid discontinuation, hematuria and proteinuria recurred, and a renal biopsy confirmed an active DDD with a majority of extracapillary crescents. Despite an increase in immunosuppressive drugs, including methylprednisolone pulses and rituximab therapy, the patient suffered acute renal failure within 3 weeks, requiring dialysis. Eculizumab treatment resulted in a quick and impressive response. Hematuria very quickly resolved, kidney function improved, and no further dialysis was required. The patient received bimonthly eculizumab injections of 600 mg, allowing for normalization of renal function and reduction of proteinuria to <0.5 g per day. Since then, she continues to receive eculizumab. Complement regulation pathway-targeted therapy may be a specific and useful treatment for rapidly progressing DDD prior to the development of glomerulosclerosis. Our data provide evidence supporting the pivotal role of complement alternative pathway

  19. Can eculizumab be discontinued in aHUS?

    PubMed Central

    Sahutoglu, Tuncay; Basturk, Taner; Sakaci, Tamer; Koc, Yener; Ahbap, Elbis; Sevinc, Mustafa; Kara, Ekrem; Akgol, Cuneyt; Caglayan, Feyza Bayraktar; Unsal, Abdulkadir; Daha, Mohamed R.

    2016-01-01

    Abstract Background: The management of atypical hemolytic uremic syndrome (aHUS) has evolved into better control of thrombotic microangiopathy (TMA) and recovery of renal functions since the recent introduction of the terminal complement cascade blocker, eculizumab, into clinical use. Better characterization of genotype–phenotype relations has become possible with genetic and clinical studies. However, these advances brought up some important issues, such as the possibility and timing of discontinuation of eculizumab and strategy of follow-up that need to be enlightened. Case Summary: One of our aHUS cases with a novel complement factor H mutation, who developed unusual laboratory findings (thrombocytopenia and mild creatinine elevation without other features of TMA) following discontinuation of eculizumab was presented. Literature and case reports relevant to discontinuation of eculizumab in aHUS patients were reviewed. Conclusion: Limited experience suggests that the risk of recurrence of TMA following discontinuation of eculizumab is relatively low for patients with MCP mutations, homozygous CFHR3/R1 deletions, anti-CFH antibodies, CFI mutations, and no identifiable mutations, whereas there is a major risk for patients with CFH mutations. Early detection of TMA recurrence and prompt retreatment with eculizumab seem to be efficient in controlling of TMA and restoration of kidney functions. PMID:27495036

  20. Endothelial proliferation in paroxysmal nocturnal hemoglobinuria.

    PubMed

    Gartner, J C; Hashida, Y; O'Gorman, M; Jaffe, R

    1988-01-01

    Paroxysmal nocturnal hemoglobinuria (PNH) is a disorder of stem cells that is associated with venous thrombosis in multiple organ sites. We present a patient with necrotizing pharyngitis and intestinal infarction who has classic laboratory findings for PNH: positive complement-mediated acid and sucrose hemolysis and absence of decay accelerating factor (DAF) in peripheral blood leukocytes. Histopathologic examination of tissue from tonsil and large bowel demonstrated not only venous thrombosis but unusual proliferation of endothelial cells (papillary endothelial hyperplasia). This has not been described previously. We speculate that the endothelial cell in PNH may share in the defective regulation of complement activity. Venous thrombosis could precipitate or be a consequence of these vascular changes.

  1. Clinical roundtable monograph: Paroxysmal nocturnal hemoglobinuria: a case-based discussion.

    PubMed

    Szer, Jeff; Hill, Anita; Weitz, Ilene Ceil

    2012-11-01

    Paroxysmal nocturnal hemoglobinuria (PNH) is a rare, acquired disorder characterized by chronic intravascular hemolysis as the primary clinical manifestation and morbidities that include anemia, thrombosis, renal impairment, pulmonary hypertension, and bone marrow failure. The prevalence of the PNH clone (from <1-100% PNH granulocytes) is approximately 16 per million, and careful monitoring is required. The average age of onset of the clinical disease is the early 30s, although it can present at all ages. PNH is caused by the acquisition of a somatic mutation of the gene phosphatidylinositol glycan anchor (PIG-A) in a multipotent hematopoietic stem cell (HSC), with clonal expansion of the mutated HSC. The mutation causes a deficiency in the synthesis of glycosylphosphatidylinositol (GPI). In cells derived from normal HSCs, the complement regulatory proteins CD55 and CD59 are anchored to the hematopoietic cell membrane surface via GPI, protecting the cells from complement-mediated lysis. However, in patients with PNH, these 2 proteins, along with numerous other GPI-linked proteins, are absent from the cell surface of red cells, granulocytes, monocytes, and platelets, resulting in complement-mediated intravascular hemolysis and other complications. Lysis of red blood cells is the most obvious manifestation, but as other cell lineages are also affected, this complement-mediated attack contributes to additional complications, such as thrombosis. Eculizumab, a humanized monoclonal antibody against the C5 complement protein, is the only effective drug therapy for PNH patients. The antibody prevents cleavage of the C5 protein by C5 convertase, in turn preventing generation of C5b-9 and release of C5a, thereby protecting from hemolysis of cells lacking the CD59 surface protein and other complications associated with complement activation. Drs. Ilene C. Weitz, Anita Hill, and Jeff Szer discuss 3 recent cases of patients with PNH.

  2. Eculizumab for atypical hemolytic-uremic syndrome in India: First report from India and the challenges faced.

    PubMed

    Sethi, S K; Rohatgi, S; Dragon-Durey, M A; Raghunathan, V; Dhaliwal, M; Rawat, A; Jha, P; Bansal, S B; Raina, R; Kher, V

    2017-01-01

    Much progress has been made in understanding the pathophysiology and treatment of atypical hemolytic uremic syndrome (aHUS). Plasma therapy is the mainstay of treatment for aHUS. The availability of the first effective anti-complement therapeutic agent, eculizumab, has dramatically changed the outlook of this disease. However, its use in clinical practice raises important questions, such as who should receive the drug, when to start such therapy, and is it safe to stop treatment once the disease is controlled. We describe here for the 1(st) time in India, use of eculizumab in a 12-year-old boy with aHUS. We also describe in this report challenges faced in procuring the drug, and an ideal, evidence-based method of treating aHUS in children.

  3. Eculizumab for atypical hemolytic-uremic syndrome in India: First report from India and the challenges faced

    PubMed Central

    Sethi, S. K.; Rohatgi, S.; Dragon-Durey, M. A.; Raghunathan, V.; Dhaliwal, M.; Rawat, A.; Jha, P.; Bansal, S. B.; Raina, R.; Kher, V.

    2017-01-01

    Much progress has been made in understanding the pathophysiology and treatment of atypical hemolytic uremic syndrome (aHUS). Plasma therapy is the mainstay of treatment for aHUS. The availability of the first effective anti-complement therapeutic agent, eculizumab, has dramatically changed the outlook of this disease. However, its use in clinical practice raises important questions, such as who should receive the drug, when to start such therapy, and is it safe to stop treatment once the disease is controlled. We describe here for the 1st time in India, use of eculizumab in a 12-year-old boy with aHUS. We also describe in this report challenges faced in procuring the drug, and an ideal, evidence-based method of treating aHUS in children. PMID:28182046

  4. Remission of aHUS neurological damage with eculizumab

    PubMed Central

    Ávila, Ana; Vizcaíno, Belén; Molina, Pablo; Gavela, Eva; Perez-Ebri, Maria; Pallardó, Luís

    2015-01-01

    Atypical haemolytic uraemic syndrome (aHUS) is a rare disease characterized by haemolytic microangiopathic anaemia, thrombocytopaenia and acute onset of renal failure, in the absence of Escherichia coli infection. Renal damage usually progresses to end-stage renal disease (ESRD), sometimes being accompanied by signs of extrarenal thrombotic microangiopathy (TMA). We report a case of full neurological and haematological recovery after eculizumab treatment in a patient with ESRD secondary to chronic aHUS refractory to plasmatherapy while she was under dialysis. It highlights the use of eculizumab for controlling extrarenal manifestations of aHUS in this population. PMID:25815183

  5. Neutral evolution in paroxysmal nocturnal hemoglobinuria

    PubMed Central

    Dingli, David; Luzzatto, Lucio; Pacheco, Jorge M.

    2008-01-01

    Paroxysmal nocturnal hemoglobinuria is an acquired hematopoietic stem cell (HSC) disorder characterized by the partial or complete deficiency of glycosyl-phosphatidylinositol (GPI)-linked membrane proteins, which leads to intravascular hemolysis. A loss of function mutation in the PIG-A gene, required for GPI biosynthesis, explains how the deficiency of many membrane proteins can result from a single genetic event. However, to date the mechanism of expansion of the GPI− clone has not been fully understood. Two hypotheses have been proposed: A selective advantage of GPI− cells because of a second mutation or a conditional growth advantage of GPI− cells in the presence of an immune attack on normal (GPI+) HSCs. Here, we explore a third possibility, whereby the PNH clone does not have a selective advantage. Simulations in a large virtual population accurately reproduce the known incidence of the disease; and the fit is optimized when the number of stem cells is decreased, reflecting a component of bone marrow failure in PNH. The model also accounts for the occurrence of spontaneous cure in PNH, consequent on clonal extinction. Thus, a clonal advantage may not be always necessary to explain clonal expansion in PNH. PMID:19011109

  6. Eculizumab in AQP4-IgG-positive relapsing neuromyelitis optica spectrum disorders: an open-label pilot study.

    PubMed

    Pittock, Sean J; Lennon, Vanda A; McKeon, Andrew; Mandrekar, Jay; Weinshenker, Brian G; Lucchinetti, Claudia F; O'Toole, Orna; Wingerchuk, Dean M

    2013-06-01

    Complement activation after binding of an IgG autoantibody to aquaporin 4 (AQP4) is thought to be a major determinant of CNS inflammation and astrocytic injury in neuromyelitis optica. The aim of this study was to investigate the use of eculizumab--a therapeutic monoclonal IgG that neutralises the complement protein C5--in neuromyelitis optica spectrum disorders. Between Oct 20, 2009, and Nov 3, 2010, we recruited patients from two US centres into an open-label trial. Patients were AQP4-IgG-seropositive, aged at least 18 years, had a neuromyelitis optica spectrum disorder, and had at least two attacks in the preceding 6 months or three in the previous 12 months. Patients received meningococcal vaccine at a screening visit and 2 weeks later began eculizumab treatment. They received 600 mg intravenous eculizumab weekly for 4 weeks, 900 mg in the fifth week, and then 900 mg every 2 weeks for 48 weeks. The coprimary endpoints were efficacy (measured by number of attacks [new worsening of neurological function lasting for more than 24 h and not attributable to an identifiable cause]) and safety. Secondary endpoints were disability (measured by expanded disability status scale), ambulation (Hauser score), and visual acuity. At follow-up visits (after 6 weeks and 3, 6, 9, and 12 months of treatment; and 3 and 12 months after discontinuation), complete neurological examination was undertaken and an adverse event questionnaire completed. This trial is registered with ClinicalTrials.gov, number NCT00904826. We enrolled 14 patients, all of whom were women. After 12 months of eculizumab treatment, 12 patients were relapse free; two had had possible attacks. The median number of attacks per year fell from three before treatment (range two to four) to zero (zero to one) during treatment (p<0·0001). No patient had worsened disability by any outcome measure. Median score on the expanded disability status scale improved from 4·3 (range 1·0-8·0) before treatment to 3·5 (0-8·0

  7. First Treatment of Relapsing Rapidly Progressive IgA Nephropathy With Eculizumab After Living Kidney Donation: A Case Report.

    PubMed

    Herzog, A L; Wanner, C; Amann, K; Lopau, K

    2017-09-01

    IgA nephropathy (IGAN) rarely can present as a crescent and progressive form leading to end-stage renal disease (ESRD) in a short period of time. Recurrence of IGAN after kidney transplantation is frequent, and complement components such as C3, C4d, and C5 seem to be involved. We present a case of a young male patient with ESRD caused by rapidly progressive IGAN and who demonstrated rapid recurrence of crescentic IGAN after kidney donation. In September 2014, a 28-year-old male patient was hospitalized due to IGAN with 60% of crescents. Cyclophosphamide, steroids, and plasmapheresis did not prevent ESRD. After 8 months of peritoneal dialysis, the patient received a blood group-compatible living donor kidney from his 57-year-old mother. Immunosuppression consisted of tacrolimus, mycophenolic acid, and steroids without induction therapy. Acute graft failure occurred 2 months later, and graft biopsy results revealed recurrence of crescentic IGAN. Cyclophosphamide was added to tacrolimus and steroid treatment, but graft function could not be restored despite viable kidney tissue in repeated biopsy specimens. Rescue therapy with 4 single doses of eculizumab was introduced while hemodialysis had already been initiated. After a cumulative dose of 1800 mg of eculizumab, kidney function did not recover. In this case, eculizumab was not effective in treating IGAN recurrence after transplantation. Therapy was started late when hemodialysis had already been initiated; an earlier start of therapy might be more effective. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. A Prospective, Multicenter, Randomized Phase II Study to Evaluate the Efficacy and Safety of Eculizumab in Patients with Guillain-Barré Syndrome (GBS): Protocol of Japanese Eculizumab Trial for GBS (JET-GBS)

    PubMed Central

    Yamaguchi, Nobuko; Sato, Yasunori; Nagashima, Kengo; Katayama, Kanako; Sekiguchi, Yukari; Iwai, Yuta; Amino, Hiroshi; Suichi, Tomoki; Yokota, Takanori; Nishida, Yoichiro; Kohara, Nobuo; Hirata, Koichi; Nishiyama, Kazutoshi; Yabe, Ichiro; Kaida, Ken-Ichi; Suzuki, Norihiro; Nodera, Hiroyuki; Tsuji, Shoji; Koike, Haruki; Kira, Jun-Ichi; Hanaoka, Hideki; Kusunoki, Susumu; Kuwabara, Satoshi

    2016-01-01

    Background Guillain-Barré syndrome (GBS) is an immune-mediated neuropathy that causes acute flaccid paralysis. Immunoglobulin and plasma exchange are established treatments for GBS; however, a substantial number of patients, particularly those with severe disease, have poor recovery and residual deficits. Recent studies suggest that complement activation plays a pivotal role in GBS-associated axonal degeneration, and eculizumab is a humanized monoclonal antibody that specifically binds to complement component 5 and potently inhibits complement activation. Objective This clinical trial aims to evaluate the efficacy and safety of eculizumab, a humanized monoclonal antibody directed against complement component 5, for treatment of GBS. Methods The Japanese Eculizumab Trial for GBS (JET-GBS) is a prospective, multicenter, placebo-controlled, double-blind, randomized phase II study conducted at 13 tertiary neurology centers and is funded by the Japan Agency for Medical Research and Development. A total of 33 GBS patients unable to walk independently within 2 weeks from symptom onset (Hughes functional grade 3-5) were randomized at a 2:1 ratio to receive either intravenous eculizumab (900 mg/day) or placebo once weekly for 4 weeks, followed by 20 weeks of follow-up. The primary endpoint for efficacy is the proportion of patients who regain their ability to walk without aid at 4 weeks after the first dose of the study treatment, while primary safety outcomes are the incidence of adverse events and serious adverse events during the trial. Results Enrollment for the trial began in August 2015. This trial is still ongoing. All participants have been enrolled, and follow-up will be completed in October 2016. Conclusions This study is the first to investigate the efficacy and safety of eculizumab for GBS. In case of a positive result, we will plan a phase III trial to investigate this issue in a larger number of patients. ClinicalTrial UMIN Clinical Trials Registry UMIN

  9. Eculizumab Therapy in Children with Severe Hematopoietic Stem Cell Transplantation–Associated Thrombotic Microangiopathy

    PubMed Central

    Jodele, Sonata; Fukuda, Tsuyoshi; Vinks, Alexander; Mizuno, Kana; Laskin, Benjamin L.; Goebel, Jens; Dixon, Bradley P.; Teusink, Ashley; Pluthero, Fred G.; Lu, Lily; Licht, Christoph; Davies, Stella M.

    2017-01-01

    We recently observed that dysregulation of the complement system may be involved in the pathogenesis of hematopoietic stem cell transplantation–associated thrombotic microangiopathy (HSCT-TMA). These findings suggest that the complement inhibitor eculizumab could be a therapeutic option for this severe HSCT complication with high mortality. However, the efficacy of eculizumab in children with HSCT-TMA and its dosing requirements are not known. We treated 6 children with severe HSCT-TMA using eculizumab and adjusted the dose to achieve a therapeutic level >99 μg/mL. HSCT-TMA resolved over time in 4 of 6 children after achieving therapeutic eculizumab levels and complete complement blockade, as measured by low total hemolytic complement activity (CH50). To achieve therapeutic drug levels and a clinical response, children with HSCT-TMA required higher doses or more frequent eculizumab infusions than currently recommended for children with atypical hemolytic uremic syndrome. Two critically ill patients failed to reach therapeutic eculizumab levels, even after dose escalation, and subsequently died. Our data indicate that eculizumab may be a therapeutic option for HSCT-TMA, but HSCT patients appear to require higher medication dosing than recommended for other conditions. We also observed that a CH50 level ≤ 4 complement activity enzyme units correlated with therapeutic eculizumab levels and clinical response, and therefore CH50 may be useful to guide eculizumab dosing in HSCT patients as drug level monitoring is not readily available. PMID:24370861

  10. Eculizumab for the treatment of preeclampsia/HELLP syndrome.

    PubMed

    Burwick, R M; Feinberg, B B

    2013-02-01

    Severe preeclampsia with hemolysis, elevated liver enzymes and low platelets (HELLP) syndrome is a leading cause of maternal and neonatal morbidity and mortality worldwide. Occurrence at an extremely premature gestational age is most challenging as there are dichotomous imperatives: delivery as definitive therapy for maternal health vs. prolongation of pregnancy to avoid prematurity and associated morbidities. We describe a patient presenting with severe preeclampsia/HELLP syndrome at 26 weeks gestation that was treated with Eculizumab, a targeted inhibitor of complement protein C5, which resulted in marked clinical improvement and complete normalization of lab parameters. Pregnancy was prolonged 17 days, likely resulting in a reduction of neonatal morbidity with its associated short and long-term health care costs. Successful use of Eculizumab in this case suggests that complement inhibition may be an effective treatment strategy for severe preeclampsia/HELLP syndrome.

  11. Complement activation and effect of eculizumab in scleroderma renal crisis

    PubMed Central

    Devresse, Arnaud; Aydin, Selda; Le Quintrec, Moglie; Demoulin, Nathalie; Stordeur, Patrick; Lambert, Catherine; Gastoldi, Sara; Pirson, Yves; Jadoul, Michel; Morelle, Johann

    2016-01-01

    Abstract Background: Scleroderma renal crisis (SRC) is a life-threatening complication of systemic sclerosis characterized by abrupt onset of hypertension, thrombotic microangiopathy, and kidney injury. The mechanisms of the disease remain ill-defined, but a growing body of evidence suggests that activation of the complement system may be involved. Methods: Here, we report the case of a patient presenting with severe SRC and strong evidence of complement activation, both in serum and in the kidney, in the absence of genetic defect of the complement system. Results: Immunofluorescence studies on kidney biopsy showed significant deposits of C1q and C4d in the endothelium of renal arterioles, pointing toward activation of the classical pathway. Because of the dramatic clinical and histological severity, and the lack of response to early treatment with angiotensin-converting enzyme inhibitors, calcium channel blockers and plasma exchange, the patient was treated with the specific C5 blocker eculizumab. Contrarily to conventional treatment, eculizumab efficiently blocked C5b-9 deposition ex vivo and maintained hematological remission. Unfortunately, the patient died from heart failure a few weeks later. Postmortem examination of the heart showed diffuse patchy interstitial fibrosis, the typical lesion of systemic sclerosis-related cardiomyopathy, but normal coronary arteries and myocardial microvasculature. Conclusion: SRC may lead to complement system activation through the classical pathway. Early administration of C5 inhibitor eculizumab may have therapeutic potential in patients with life-threatening SRC refractory to conventional treatment using angiotensin-converting enzyme inhibitors. PMID:27472742

  12. Technical advances in flow cytometry-based diagnosis and monitoring of paroxysmal nocturnal hemoglobinuria

    PubMed Central

    Correia, Rodolfo Patussi; Bento, Laiz Cameirão; Bortolucci, Ana Carolina Apelle; Alexandre, Anderson Marega; Vaz, Andressa da Costa; Schimidell, Daniela; Pedro, Eduardo de Carvalho; Perin, Fabricio Simões; Nozawa, Sonia Tsukasa; Mendes, Cláudio Ernesto Albers; Barroso, Rodrigo de Souza; Bacal, Nydia Strachman

    2016-01-01

    ABSTRACT Objective: To discuss the implementation of technical advances in laboratory diagnosis and monitoring of paroxysmal nocturnal hemoglobinuria for validation of high-sensitivity flow cytometry protocols. Methods: A retrospective study based on analysis of laboratory data from 745 patient samples submitted to flow cytometry for diagnosis and/or monitoring of paroxysmal nocturnal hemoglobinuria. Results: Implementation of technical advances reduced test costs and improved flow cytometry resolution for paroxysmal nocturnal hemoglobinuria clone detection. Conclusion: High-sensitivity flow cytometry allowed more sensitive determination of paroxysmal nocturnal hemoglobinuria clone type and size, particularly in samples with small clones. PMID:27759825

  13. Eculizumab, a terminal complement inhibitor, improves anaemia in patients with paroxysmal nocturnal haemoglobinuria.

    PubMed

    Schubert, Jörg; Hillmen, Peter; Röth, Alexander; Young, Neal S; Elebute, Modupe O; Szer, Jeffrey; Gianfaldoni, Giacomo; Socié, Gérard; Browne, Paul; Geller, Robert; Rother, Russell P; Muus, Petra

    2008-06-01

    In paroxysmal nocturnal haemoglobinuria (PNH), chronic destruction of PNH red blood cells (RBCs) by complement leads to anaemia and other serious morbidities. Eculizumab inhibits terminal complement-mediated PNH RBC destruction by targeting C5. In the phase III, double-blind, placebo-controlled, TRIUMPH study, eculizumab reduced haemolysis, stabilized haemoglobin levels, reduced transfusion requirements and improved fatigue in patients with PNH. Herein, we explored the effects of eculizumab on measures of anaemia in patients from the TRIUMPH study and the open-label SHEPHERD study, a more heterogeneous population. Eculizumab reduced haemolysis regardless of pretreatment transfusion requirements and regardless of whether or not patients became transfusion-dependent during treatment (P < 0.001). Reduction in haemolysis was associated with increased PNH RBC counts (P < 0.001) while reticulocyte counts remained elevated. Eculizumab-treated patients demonstrated significantly higher levels of haemoglobin as compared with placebo in TRIUMPH and relative to baseline levels in SHEPHERD (P < 0.001 for each study). Eculizumab lowered transfusion requirement across multiple pretreatment transfusion strata and eliminated transfusion support in a majority of both TRIUMPH and SHEPHERD patients (P < 0.001). Patients who required some transfusion support during treatment with eculizumab showed a reduction in haemolysis and transfusion requirements and an improvement in fatigue. Eculizumab reduces haemolysis and improves anaemia and fatigue, regardless of transfusion requirements.

  14. Current evidence on the discontinuation of eculizumab in patients with atypical haemolytic uraemic syndrome

    PubMed Central

    Macia, Manuel; de Alvaro Moreno, Fernando; Dutt, Tina; Fehrman, Ingela; Hadaya, Karine; Gasteyger, Christoph

    2017-01-01

    Abstract Background. Atypical haemolytic uraemic syndrome (aHUS) is a rare, life-threatening disorder for which eculizumab is the only approved treatment. Life-long treatment is indicated; however, eculizumab discontinuation has been reported. Methods. Unpublished authors’ cases and published cases of eculizumab discontinuation are reviewed. We also report eculizumab discontinuation data from five clinical trials, plus long-term extensions and the global aHUS Registry. Results. Of six unpublished authors’ cases, four patients had a subsequent thrombotic microangiopathy (TMA) manifestation within 12 months of discontinuation. Case reports of 52 patients discontinuing eculizumab were identified; 16 (31%) had a subsequent TMA manifestation. In eculizumab clinical trials, 61/130 patients discontinued treatment between 2008 and 2015. Median follow-up post-discontinuation was 24 weeks and during this time 12 patients experienced 15 severe TMA complications and 9 of the 12 patients restarted eculizumab. TMA complications occurred irrespective of identified genetic mutation, high risk polymorphism or auto-antibody. In the global aHUS Registry, 76/296 patients (26%) discontinued, 12 (16%) of whom restarted. Conclusions. The currently available evidence suggests TMA manifestations following discontinuation are unpredictable in both severity and timing. For evidence-based decision making, better risk stratification and valid monitoring strategies are required. Until these exist, the risk versus benefit of eculizumab discontinuation, either in specific clinical situations or at selected time points, should include consideration of the risk of further TMA manifestations. PMID:28621343

  15. Critical appraisal of eculizumab for atypical hemolytic uremic syndrome.

    PubMed

    Palma, Lilian M Pereira; Langman, Craig B

    2016-01-01

    The biology of atypical hemolytic uremic syndrome has been shown to involve inability to limit activation of the alternative complement pathway, with subsequent damage to systemic endothelial beds and the vasculature, resulting in the prototypic findings of a thrombotic microangiopathy. Central to this process is the formation of the terminal membrane attack complex C5b-9. Recently, application of a monoclonal antibody that specifically binds to C5, eculizumab, became available to treat patients with atypical hemolytic uremic syndrome, replacing plasma exchange or infusion as primary therapy. This review focuses on the evidence, based on published clinical trials, case series, and case reports, on the efficacy and safety of this approach.

  16. Hematopoietic stem cell transplantation for paroxysmal nocturnal hemoglobinuria: long-term results of a retrospective study on behalf of the Gruppo Italiano Trapianto Midollo Osseo (GITMO)

    PubMed Central

    Santarone, Stella; Bacigalupo, Andrea; Risitano, Antonio M.; Tagliaferri, Elena; Di Bartolomeo, Erminia; Iori, Anna Paola; Rambaldi, Alessandro; Angelucci, Emanuele; Spagnoli, Alessandra; Papineschi, Federico; Tamiazzo, Stefania; Di Nicola, Marta; Di Bartolomeo, Paolo

    2010-01-01

    Background Paroxysmal nocturnal hemoglobinuria is an acquired clonal disorder of the hemopoietic stem cells for which the only curative treatment is allogeneic hematopoietic stem cell transplantation. Design and Methods The aim of this retrospective study was to assess the long-term clinical and hematologic results in 26 paroxysmal nocturnal hemoglobinuria patients who received hematopoietic stem cell transplantation in Italy between 1988 and 2006. The patients were aged 22 to 60 years (median 32 years). Twenty-three donors were HLA-identical (22 siblings and one unrelated) and 3 were HLA-mismatched (2 related and one unrelated). Results Fifteen patients received a myeloablative conditioning consisting of busulfan and cyclophosphamide (in all cases from identical donor) and 11 were given a reduced intensity conditioning (8 from identical donor and 3 from mismatched donor). The cumulative incidence of graft failure was 8% (4% primary and 4% secondary graft failure). Transplant-related mortality for all patients was 42% (26% and 63% for patients transplanted following myeloablative or reduced intensity conditioning, respectively). As of October 31, 2009, 15 patients (11 in the myeloablative conditioning group and 4 in the reduced intensity conditioning group) are alive with complete hematologic recovery and no evidence of paroxysmal nocturnal hemoglobinuria following a median follow-up of 131 months (range 30–240). The 10-year Kaplan-Meier probability of disease-free survival was 57% for all patients: 65% for 23 patients transplanted from identical donor and 73% for 15 patients transplanted with myeloablative conditioning. No thromboembolic event nor recurrence of the disease were reported following transplant. Conclusions The findings of this study confirm that most patients with paroxysmal nocturnal hemoglobinuria may be definitively cured with hematopoietic stem cell transplantation. PMID:20007144

  17. Eculizumab Induces Sustained Remission in a Patient With Refractory Primary Catastrophic Antiphospholipid Syndrome.

    PubMed

    Zikos, Thomas A; Sokolove, Jeremy; Ahuja, Neera; Berube, Caroline

    2015-09-01

    Catastrophic antiphospholipid syndrome (CAPS) is fatal in approximately 44% of patients in whom the diagnosis is made, thus demonstrating the inadequacy of current medical therapy. In this report, we discuss a 47-year-old man with a known history of primary antiphospholipid syndrome, who presented with CAPS after undergoing cholecystectomy and a treatment-refractory early relapse after development of colitis. Given the potential therapeutic efficacy of complement inhibition in antiphospholipid syndrome, the patient was administered eculizumab, a terminal complement inhibitor. Progressive clinical improvement and laboratory improvement were observed upon initiation of eculizumab. He has remained in remission for over 16 months of follow-up while on eculizumab. In conclusion, this case represents successful use of eculizumab for the treatment of primary CAPS.

  18. Case report: Benefits and challenges of long-term eculizumab in atypical hemolytic uremic syndrome.

    PubMed

    Cullinan, Noelle; Gorman, Kathleen Mary; Riordan, Michael; Waldron, Mary; Goodship, Timothy H J; Awan, Atif

    2015-06-01

    Atypical hemolytic uremic syndrome (aHUS) is caused by dysregulation of the complement system, leading to complement overactivation. A humanized anti-C5 monoclonal antibody, eculizumab, has been available for the treatment of aHUS since 2011. The long-term safety and efficacy of this novel drug in the pediatric population remain under review. We present a child with a hybrid CFH/CFHR3 gene who, having had multiple disease relapses despite optimal treatment with plasma exchange, commenced eculizumab therapy in August 2010. She remains relapse free in follow-up at 52 months, and treatment has been well tolerated. The risk of meningococcal disease during this treatment is recognized. Despite vaccination against meningococcal disease and appropriate antibiotic prophylaxis, our patient developed meningococcal bacteremia 30 months into treatment. She presented with nonspecific symptoms but recovered without sequelae with appropriate treatment. We recommend that children be vaccinated against invasive meningococcal infection before beginning eculizumab therapy and take appropriate antibiotic prophylaxis during treatment, and we suggest that vaccine responses should be checked and followed annually. Clinicians need to maintain a high index of suspicion for invasive meningococcal disease. Neither vaccination nor antibiotic prophylaxis provides complete protection in patients on eculizumab therapy. The appropriate dosage of eculizumab needed to achieve remission in aHUS in the pediatric population is unknown. Having achieved remission in our patient, we monitor eculizumab and CH50 levels to evaluate ongoing blockade of the terminal complement cascade. Such information may help guide dosing intervals in the future.

  19. Adjustment of Eculizumab Dosage Pattern in Patients with Atypical Hemolytic Uremic Syndrome with Suboptimal Response to Standard Treatment Pattern

    PubMed Central

    Peralta Roselló, Carmen; Baltar Martín, José María; Castillo Eraso, Lorena; de Álvaro Moreno, Fernando; Martínez Vea, Alberto; Visus-Fernández de Manzanos, María Teresa

    2016-01-01

    In patients with atypical hemolytic uremic syndrome (aHUS), complement blocking by eculizumab rapidly halts the process of thrombotic microangiopathy and it is associated with clear long-term hematologic and renal improvements. Eculizumab treatment consists of a 4-week initial phase with weekly IV administration of 900 mg doses, followed by a maintenance phase with a 1,200 mg dose in the fifth week and every 14 ± 2 days thereafter. We present three patients with aHUS and suboptimal response to eculizumab treatment at the usual administration dosage who showed hematologic and renal improvements after an adjustment in the eculizumab treatment protocol. PMID:28025630

  20. Critical appraisal of eculizumab for atypical hemolytic uremic syndrome

    PubMed Central

    Palma, Lilian M Pereira; Langman, Craig B

    2016-01-01

    The biology of atypical hemolytic uremic syndrome has been shown to involve inability to limit activation of the alternative complement pathway, with subsequent damage to systemic endothelial beds and the vasculature, resulting in the prototypic findings of a thrombotic microangiopathy. Central to this process is the formation of the terminal membrane attack complex C5b-9. Recently, application of a monoclonal antibody that specifically binds to C5, eculizumab, became available to treat patients with atypical hemolytic uremic syndrome, replacing plasma exchange or infusion as primary therapy. This review focuses on the evidence, based on published clinical trials, case series, and case reports, on the efficacy and safety of this approach. PMID:27110144

  1. Efficacy of eculizumab in a patient with immunoadsorption-dependent catastrophic antiphospholipid syndrome: a case report.

    PubMed

    Kronbichler, Andreas; Frank, Renate; Kirschfink, Michael; Szilágyi, Ágnes; Csuka, Dorottya; Prohászka, Zoltán; Schratzberger, Peter; Lhotta, Karl; Mayer, Gert

    2014-11-01

    Catastrophic antiphospholipid syndrome (CAPS) is a rare but devastating complication in patients with antiphospholipid syndrome (APS) with a high morbidity and mortality.We describe a case of a 30-year old female patient with immunoglobulin A (IgA) deficiency who underwent splenectomy because of idiopathic thrombocytopenic thrombocytopenia. Subsequently, an APS and finally systemic lupus erythematosus was diagnosed. After an uncomplicated pregnancy that was terminated by cesarean section, the patient developed severe CAPS with cerebral, myocardial, renal, and pulmonary involvement.Because of IgA deficiency, standard therapy consisting of plasmapheresis and intravenous immunoglobulins in addition to steroids was not tolerated. After 8 sessions of immunoadsorption (IAS), massive pulmonary hemorrhage was controlled but relapsed twice whenever IAS was terminated. As other immunosuppressive agents were considered dangerous because of the risk of infections in the face of severe hypogammaglobulinemia, we administered eculizumab, an inhibitor of the terminal complement pathway, which led to a persistent control of her disease. Interestingly, eculizumab therapy was associated with a further decline of complement C3 and C4 serum levels. The patient developed a subsequent flare of her systemic lupus erythematosus, potentially indicating that complement inhibition by eculizumab is not effective in preventing lupus flares.Taken together, we describe a unique case of life-threatening and difficult-to-treat CAPS with a good clinical response after terminal complement complex inhibition with eculizumab. Further controlled trials are necessary to investigate the value of eculizumab in patients with CAPS.

  2. Pregnant Woman with Atypical Hemolytic Uremic Syndrome Delivered a Healthy Newborn under Eculizumab Treatment

    PubMed Central

    Demir, Erol; Yazici, Halil; Ozluk, Yasemin; Kilicaslan, Isin; Turkmen, Aydin

    2016-01-01

    Pregnancy-associated thrombotic microangiopathy is a very rare condition; however, it significantly increases fetal or maternal morbidity and mortality. Pregnancy may trigger atypical hemolytic uremic syndrome (aHUS) or thrombotic thrombocytopenic purpura. The risk for pregnancy-associated aHUS is highest during the second pregnancy. The outcome is usually poor with 50–60% mortality; renal dysfunction and hypertension are the rule in those who survive the acute episode. After the development of complement regulation mechanisms and aHUS pathogenesis, eculizumab has been widely used as a first-line treatment in aHUS. Eculizumab has been produced to minimize immunogenicity and Fc-mediated functions, including recruitment of inflammatory cells and complement activation, and using eculizumab in first-line treatment improves kidney function. Recent studies showed that early diagnosis and rapid use of eculizumab in first-line treatment improve outcomes. We demonstrate a case with pregnancy-triggered aHUS occurring in the second trimester, who was successfully treated and delivered a healthy baby under eculizumab treatment. PMID:28101502

  3. Two cases of kidney transplantation-associated thrombotic microangiopathy successfully treated with eculizumab.

    PubMed

    Ikeda, Takashi; Okumi, Masayoshi; Unagami, Kohei; Kanzawa, Taichi; Sawada, Anri; Kawanishi, Kunio; Omoto, Kazuya; Ishida, Hideki; Tanabe, Kazunari

    2016-07-01

    Transplantation-associated thrombotic microangiopathy (TA-TMA) is relatively rare and requires immediate intervention to avoid irreversible organ damage or death; however, consensus regarding the treatment approach is lacking. Atypical haemolytic uraemic syndrome (aHUS) is a rare disease caused by dysregulation of the alternative complement pathway resulting in TMA. aHUS is histologically similar to TA-TMA; approximately 60% of TA-TMA patients have complement dysregulation. Eculizumab, a humanized anti-C5 monoclonal antibody, inhibits terminal membrane-attack complex formation and TMA progression. Eculizumab has been successfully used to treat aHUS post-transplant. We present two cases of kidney TA-TMA due to unknown causes, suspected antibody-mediated rejection, or calcineurin inhibitor (CNI)-related toxicity that developed on day 1 or 2 post-kidney transplantation. Low platelet count and haemoglobin level with red cell fragments were detected. Despite steroid pulse, plasma exchange (PE), and intravenous immunoglobulin therapy, TA-TMA did not improve; therefore, eculizumab was administered despite no genetic testing. Laboratory data, including renal function, improved immediately. TA-TMA treatment primarily involves PE initiation or CNI discontinuation; eculizumab can be used to safely treat TA-TMA and then be ceased in the short term. Therefore, eculizumab administration might be beneficial for kidney TA-TMA as early as the diagnosis of refractory to PE.

  4. Paroxysmal nocturnal hemoglobinuria and telomere length predicts response to immunosuppressive therapy in pediatric aplastic anemia.

    PubMed

    Narita, Atsushi; Muramatsu, Hideki; Sekiya, Yuko; Okuno, Yusuke; Sakaguchi, Hirotoshi; Nishio, Nobuhiro; Yoshida, Nao; Wang, Xinan; Xu, Yinyan; Kawashima, Nozomu; Doisaki, Sayoko; Hama, Asahito; Takahashi, Yoshiyuki; Kudo, Kazuko; Moritake, Hiroshi; Kobayashi, Masao; Kobayashi, Ryoji; Ito, Etsuro; Yabe, Hiromasa; Ohga, Shouichi; Ohara, Akira; Kojima, Seiji

    2015-12-01

    Acquired aplastic anemia is an immune-mediated disease characterized by severe defects in stem cell number resulting in hypocellular marrow and peripheral blood cytopenias. Minor paroxysmal nocturnal hemoglobinuria populations and a short telomere length were identified as predictive biomarkers of immunosuppressive therapy responsiveness in aplastic anemia. We enrolled 113 aplastic anemia patients (63 boys and 50 girls) in this study to evaluate their response to immunosuppressive therapy. The paroxysmal nocturnal hemoglobinuria populations and telomere length were detected by flow cytometry. Forty-seven patients (42%) carried a minor paroxysmal nocturnal hemoglobinuria population. The median telomere length of aplastic anemia patients was -0.99 standard deviation (SD) (range -4.01-+3.01 SD). Overall, 60 patients (53%) responded to immunosuppressive therapy after six months. Multivariate logistic regression analysis identified the absence of a paroxysmal nocturnal hemoglobinuria population and a shorter telomere length as independent unfavorable predictors of immunosuppressive therapy response at six months. The cohort was stratified into a group of poor prognosis (paroxysmal nocturnal hemoglobinuria negative and shorter telomere length; 37 patients) and good prognosis (paroxysmal nocturnal hemoglobinuria positive and/or longer telomere length; 76 patients), respectively. The response rates of the poor prognosis and good prognosis groups at six months were 19% and 70%, respectively (P<0.001). The combined absence of a minor paroxysmal nocturnal hemoglobinuria population and a short telomere length is an efficient predictor of poor immunosuppressive therapy response, which should be considered while deciding treatment options: immunosuppressive therapy or first-line hematopoietic stem cell transplantation. The trial was registered in www.umin.ac.jp with number UMIN000017972.

  5. Complement in paroxysmal nocturnal hemoglobinuria: exploiting our current knowledge to improve the treatment landscape

    PubMed Central

    Mastellos, Dimitrios C; Ricklin, Daniel; Yancopoulou, Despina; Risitano, Antonio; Lambris, John D

    2015-01-01

    Paroxysmal nocturnal hemoglobinuria (PNH) is a rare hematological disorder associated with an acquired deficiency in glycophosphatidylinositol-anchor biosynthesis that renders erythrocytes susceptible to complement attack. Intravascular hemolysis via the membrane attack complex is a clinical hallmark of the disease, and C5 blockade is currently the only approved treatment for PNH. However, residual anemia is an emerging observation for many PNH patients receiving anti-C5 treatment. A range of complement-targeted therapeutic approaches, encompassing surface-directed inhibition of C3 convertases, blockade of membrane attack complex assembly or C3 interception using peptidic inhibitors, has yielded promising results and offers leverage for even more effective treatment of PNH. This article discusses recent advances in this rapidly evolving field, integrating critical perspectives from preclinical PNH models and diverse complement modulation strategies with genetic insights and therapy response profiles. It also evaluates the relative efficacy, limitations and benefits afforded by C3 or C5 inhibition in the context of PNH therapeutics. PMID:25213458

  6. Eculizumab for rescue of thrombotic microangiopathy in PM-Scl antibody-positive autoimmune overlap syndrome

    PubMed Central

    Thomas, Christie P.; Nester, Carla M.; Phan, Andrew C.; Sharma, Manisha; Steele, Amanda L.; Lenert, Petar S.

    2015-01-01

    A 46-year-old female with interstitial lung disease presented with proximal muscle weakness, worsening hypertension, microangiopathic hemolysis, thrombocytopenia and deteriorating renal function. She had no sclerodactyly, but had abnormal capillaroscopy. She tested positive for PM-Scl antibodies, and a renal biopsy showed an acute thrombotic microangiopathy consistent with scleroderma renal crisis (SRC). She failed to respond to corticosteroids, plasmapheresis and renin–angiotensin pathway inhibitors. She recovered quickly with the anti-C5 antibody, eculizumab. She had no genetic abnormalities associated with atypical hemolytic uremic syndrome except a DNA variant of unknown significance in C3. This case suggests that eculizumab may be effective for SRC. PMID:26613027

  7. An effective treatment of atypical hemolytic uremic syndrome with plasma exchange and eculizumab: A case report.

    PubMed

    Sengul Samanci, Nilay; Ayer, Mesut; Ergen, Abdulkadir; Ozturk, Savas

    2015-06-01

    Atypical hemolytic uremic syndrome is a rare thrombotic microangiopathy caused by chronic defective regulation of the complement activation. This activation results in systemic endothelial damage leading to renal failure. Eculizumab, an anti-C5 antibody, is effective in limiting complement activation in patients with aHUS and has recently came out as a therapeutic option for aHUS. Here we present a case showing that first-line eculizumab treatment successfully prevents the induction of the terminal complement cascade and blocked the progression of thrombotic microangiopathy in aHUS.

  8. Recovery with a regular dose of antibiotics from bacillary hemoglobinuria in a Holstein cow

    PubMed Central

    TAKAGI, Mitsuhiro; KOHYAMA, Moeko; ONO, Tetsushi; ADACHI, Satoshi; SHIRAO, Daiji; TAMURA, Hidenori; TANIGUCHI, Masayasu; YABUKI, Akira; YAMATO, Osamu

    2016-01-01

    One Holstein cow housed with 21 other cows exhibited clinical signs of pyrexia, anorexia and diarrhea along with severe hemoglobinuria. Hematological and biochemical analyses conducted before and after antibiotic therapy indicated severe hemolytic anemia and disruption of hepatic function. A general improvement in conditions was observed after an 11-day program of treatment comprising a regular dose of antibiotics and prescribed supportive therapies. A tentative diagnosis of bacillary hemoglobinuria was made based on the clinical and clinico-pathologic features on day 7. A molecular diagnosis was made by a PCR amplification of the flagellin gene of Clostridium haemolyticum using DNA extracted from the whole blood. The cow was diagnosed with the first recorded occurrence of bacillary hemoglobinuria of Holstein cattle in Japan. PMID:27498996

  9. Recovery with a regular dose of antibiotics from bacillary hemoglobinuria in a Holstein cow.

    PubMed

    Takagi, Mitsuhiro; Kohyama, Moeko; Ono, Tetsushi; Adachi, Satoshi; Shirao, Daiji; Tamura, Hidenori; Taniguchi, Masayasu; Yabuki, Akira; Yamato, Osamu

    2016-12-01

    One Holstein cow housed with 21 other cows exhibited clinical signs of pyrexia, anorexia and diarrhea along with severe hemoglobinuria. Hematological and biochemical analyses conducted before and after antibiotic therapy indicated severe hemolytic anemia and disruption of hepatic function. A general improvement in conditions was observed after an 11-day program of treatment comprising a regular dose of antibiotics and prescribed supportive therapies. A tentative diagnosis of bacillary hemoglobinuria was made based on the clinical and clinico-pathologic features on day 7. A molecular diagnosis was made by a PCR amplification of the flagellin gene of Clostridium haemolyticum using DNA extracted from the whole blood. The cow was diagnosed with the first recorded occurrence of bacillary hemoglobinuria of Holstein cattle in Japan.

  10. Eculizumab in anti-factor h antibodies associated with atypical hemolytic uremic syndrome.

    PubMed

    Diamante Chiodini, Benedetta; Davin, Jean-Claude; Corazza, Francis; Khaldi, Karim; Dahan, Karin; Ismaili, Khalid; Adams, Brigitte

    2014-06-01

    Atypical hemolytic uremic syndrome (aHUS) is a life-threatening multisystemic condition often leading to end-stage renal failure. It results from an increased activation of the alternative pathway of the complement system due to mutations of genes coding for inhibitors of this pathway or from autoantibodies directed against them. Eculizumab is a monoclonal antibody directed against complement component C5 and inhibiting the activation of the effector limb of the complement system. Its efficacy has already been demonstrated in aHUS. The present article reports for the first time the use of eculizumab in a patient presenting with aHUS associated with circulating anti-complement Factor H autoantibodies and complicated by cardiac and neurologic symptoms. Our observation highlights the efficacy of eculizumab in this form of aHUS not only on renal symptoms but also on the extrarenal symptoms. It also suggests that eculizumab should be used very promptly after aHUS presentation to prevent life-threatening complications and to reduce the risk of chronic disabilities. To obtain a complete inhibition of the effector limb activation, the advised dosage must be respected. After this initial therapy in the autoimmune aHUS form, a long-term immunosuppressive treatment should be considered, to prevent relapses by reducing anti-complement Factor H autoantibody plasma levels. Copyright © 2014 by the American Academy of Pediatrics.

  11. Incomplete inhibition by eculizumab: mechanistic evidence for residual C5 activity during strong complement activation.

    PubMed

    Harder, Markus J; Kuhn, Nadine; Schrezenmeier, Hubert; Höchsmann, Britta; von Zabern, Inge; Weinstock, Christof; Simmet, Thomas; Ricklin, Daniel; Lambris, John D; Skerra, Arne; Anliker, Markus; Schmidt, Christoph Q

    2017-02-23

    Eculizumab inhibits the terminal, lytic pathway of complement by blocking the activation of the complement protein C5 and shows remarkable clinical benefits in certain complement-mediated diseases. However, several reports suggest that activation of C5 is not always completely suppressed in patients even under excess of eculizumab over C5, indicating that residual C5 activity may derogate the drug's therapeutic benefit under certain conditions. By using eculizumab and the tick-derived C5 inhibitor coversin, we determined conditions ex vivo in which C5 inhibition is incomplete. The degree of such residual lytic activity depended on the strength of the complement activator and the resulting surface density of the complement activation product C3b, which autoamplifies via the alternative pathway (AP) amplification loop. We show that at high C3b densities required for binding and activation of C5, both inhibitors reduce but do not abolish this interaction. The decrease of C5 binding to C3b clusters in the presence of C5 inhibitors correlated with the levels of residual hemolysis. However, by employing different C5 inhibitors simultaneously, residual hemolytic activity could be abolished. The importance of AP-produced C3b clusters for C5 activation in the presence of eculizumab was corroborated by the finding that residual hemolysis after forceful activation of the classical pathway could be reduced by blocking the AP. By providing insights into C5 activation and inhibition, our study delivers the rationale for the clinically observed phenomenon of residual terminal pathway activity under eculizumab treatment with important implications for anti-C5 therapy in general.

  12. A randomized, double-blind, placebo-controlled phase II study of eculizumab in patients with refractory generalized myasthenia gravis.

    PubMed

    Howard, James F; Barohn, Richard J; Cutter, Gary R; Freimer, Miriam; Juel, Vern C; Mozaffar, Tahseen; Mellion, Michelle L; Benatar, Michael G; Farrugia, Maria Elena; Wang, Jing Jing; Malhotra, Suneil S; Kissel, John T

    2013-07-01

    Complement activation at the neuromuscular junction is a primary cause of acetylcholine receptor loss and failure of neuromuscular transmission in myasthenia gravis (MG). Eculizumab, a humanized monoclonal antibody, blocks the formation of terminal complement complex by specifically preventing the enzymatic cleavage of complement 5 (C5). This study was a randomized, double-blind, placebo-controlled, crossover trial involving 14 patients with severe, refractory generalized MG (gMG). Six of 7 patients treated with eculizumab for 16 weeks (86%) achieved the primary endpoint of a 3-point reduction in the quantitative myasthenia gravis (QMG) score. Examining both treatment periods, the overall change in mean QMG total score was significantly different between eculizumab and placebo (P = 0.0144). After assessing data obtained from all visits, the overall change in mean QMG total score from baseline was found to be significantly different between eculizumab and placebo (P < 0.0001). Eculizumab was well tolerated. The data suggest that eculizumab may have a role in treating severe, refractory MG. Copyright © 2013 Wiley Periodicals, Inc.

  13. Diffuse renal parenchyma uptake with bone scintigraphy in a patient with paroxysmal nocturnal hemoglobinuria and normal kidney function.

    PubMed

    Balink, Hans; Hoogendoorn, Mels; Hemmelder, Marc

    2014-03-01

    A 41-year-old woman with a Harrington spondylodesis presented with lower back pain. Bone scintigraphy showed diffusely increased parenchymal uptake in both kidneys. She reported 2 previous periods of dark, almost black, urine. Additional flow cytometric analysis confirmed the diagnosis of paroxysmal nocturnal hemoglobinuria. The increased renal parenchyma uptake is very probably due to paroxysmal nocturnal hemoglobinuria-related renal hemosiderosis. Remarkably, the patient did not develop any abnormality of renal function.

  14. Life-threatening pregnancy-associated atypical haemolytic uraemic syndrome and its response to eculizumab.

    PubMed

    Gately, Ryan; San, Aye; Kurtkoti, Jagadeesh; Parnham, Alan

    2017-02-01

    Pregnancy-associated atypical haemolytic uraemic syndrome (P-aHUS) is a rare, potentially lethal condition that can complicate pregnancy in up to 1 in 25 000 cases. Without prompt diagnosis and initiation of appropriate treatment, this condition can lead to disastrous consequences for both mother and child. Given the broad spectrum of conditions that can present similarly in the peripartum period, it is often difficult to establish the correct diagnosis in a timely manner. Recently, the terminal complement cascade inhibitor eculizumab has been used with considerable success in non-pregnancy HUS; however, its use in P-aHUS is limited to isolated case reports. Here, we present a case of fulminant P-aHUS in the postpartum period that was successfully treated with eculizumab resulting in significant recovery of renal function.

  15. A Case Report and Literature Review of Eculizumab Withdrawal in Atypical Hemolytic-Uremic Syndrome

    PubMed Central

    Quiroga, Borja; de Lorenzo, Alberto; Vega, Cristina; de Alvaro, Fernando

    2016-01-01

    Patient: Female, 37 Final Diagnosis: SHUa Symptoms: Abdominal discomfort • nausea • weakness Medication: — Clinical Procedure: — Specialty: Nephrology Objective: Unusual clinical course Background: Recent advances in the treatment of atypical hemolytic-uremic syndrome (aHUS) have resulted to better long-term survival rates for patients with this life-threatening disease. However, many questions remain such as whether or not long-term treatment is necessary in some patients and what are the risks of prolonged therapy. Case Report: Here, we discuss the case of a 37-year-old woman with CFH and CD46 genetic abnormalities who developed aHUS with severe renal failure. She was successfully treated with three doses of rituximab and a three month treatment with eculizumab. After eculizumab withdrawal, symptoms of thrombotic micro-angiopathy (TMA) recurred, therefore eculizumab treatment was restarted. The patient exhibited normal renal function and no symptoms of aHUS at one-year follow-up with further eculizumab treatment. Conclusions: This case highlights the clinical challenges of the diagnosis and management of patient with aHUS with complement-mediated TMA involvement. Attention was paid to the consequences of the treatment withdrawal. Exact information regarding genetic abnormalities and renal function associated with aHUS, as well as estimations of the relapse risk and monitoring of complement tests may provide insights into the efficacy of aHUS treatment, which will enable the prediction of therapeutic responses and testing of new treatment options. Improvements in our understanding of aHUS and its causes may facilitate the identification of patients in whom anti-complement therapies can be withdrawn without risk. PMID:27974740

  16. A Case of Atypical Hemolytic Uremic Syndrome Successfully Treated with Eculizumab

    PubMed Central

    Thajudeen, B.; Sussman, A.; Bracamonte, E.

    2013-01-01

    Atypical hemolytic uremic syndrome (aHUS) is a rare thrombotic microangiopathy (TMA) characterized by the triad of hemolytic anemia, thrombocytopenia, and acute renal failure. Eculizumab, a monoclonal complement C5 antibody which prevents the induction of the terminal complement cascade, has recently emerged as a therapeutic option for aHUS. We report a case of aHUS successfully treated with eculizumab. A 51-year-old male was admitted to the hospital following a mechanical fall. His past medical history was significant for rheumatic valve disease and mitral valve replacement; he was on warfarin for anticoagulation. A computed tomography scan of the head revealed a right-sided subdural hematoma due to coagulopathy resulting from a supratherapeutic international normalized ratio (INR). Following treatment with prothrombin complex concentrate to reverse the INR, urine output dropped and his serum creatinine subsequently increased to 247.52 μmol/l from the admission value of 70.72 μmol/l. Laboratory evaluation was remarkable for hemolytic anemia, thrombocytopenia, elevated lactate dehydrogenase (LDH), low haptoglobin, and low complement C3. A renal biopsy was consistent with TMA, favoring a diagnosis of aHUS. Treatment with eculizumab was initiated which resulted in the stabilization of his hemoglobin, platelets, and LDH. Hemodialysis was terminated after 2.5 months due to improvement in urine output and solute clearance. The interaction between thrombin and complement pathway might be responsible for the pathogenesis of aHUS in this case. Eculizumab is an effective therapeutic agent in the treatment of aHUS. Early targeting of the complement system may modify disease progression and thus treat aHUS more effectively. PMID:24570684

  17. Long-term safety and efficacy of sustained eculizumab treatment in patients with paroxysmal nocturnal haemoglobinuria

    PubMed Central

    Hillmen, Peter; Muus, Petra; Röth, Alexander; Elebute, Modupe O; Risitano, Antonio M; Schrezenmeier, Hubert; Szer, Jeffrey; Browne, Paul; Maciejewski, Jaroslaw P; Schubert, Jörg; Urbano-Ispizua, Alvaro; de Castro, Carlos; Socié, Gérard; Brodsky, Robert A

    2013-01-01

    Paroxysmal nocturnal haemoglobinuria (PNH) is characterized by chronic, uncontrolled complement activation resulting in elevated intravascular haemolysis and morbidities, including fatigue, dyspnoea, abdominal pain, pulmonary hypertension, thrombotic events (TEs) and chronic kidney disease (CKD). The long-term safety and efficacy of eculizumab, a humanized monoclonal antibody that inhibits terminal complement activation, was investigated in 195 patients over 66 months. Four patient deaths were reported, all unrelated to treatment, resulting in a 3-year survival estimate of 97·6%. All patients showed a reduction in lactate dehydrogenase levels, which was sustained over the course of treatment (median reduction of 86·9% at 36 months), reflecting inhibition of chronic haemolysis. TEs decreased by 81·8%, with 96·4% of patients remaining free of TEs. Patients also showed a time-dependent improvement in renal function: 93·1% of patients exhibited improvement or stabilization in CKD score at 36 months. Transfusion independence increased by 90·0% from baseline, with the number of red blood cell units transfused decreasing by 54·7%. Eculizumab was well tolerated, with no evidence of cumulative toxicity and a decreasing occurrence of adverse events over time. Eculizumab has a substantial impact on the symptoms and complications of PNH and results a significant improvement in patient survival. PMID:23617322

  18. Renal recovery with eculizumab in atypical hemolytic uremic syndrome following prolonged dialysis.

    PubMed

    Povey, Hannah; Vundru, Rahul; Junglee, Naushad; Jibani, Mahdi

    2014-11-01

    Hemolytic uremic syndrome (HUS) is a thrombotic microangiopathy (TMA) which encompasses hemolytic anemia, thrombocytopenia, and organ impairment. Around 10% of cases are atypical HUS (aHUS), a rare disease with poor outcomes caused by uncontrolled activation of the alternative complement pathway. This case describes a young woman with clinical manifestations compatible with TMA during childhood and adolescence who was formally diagnosed with aHUS at the age of 21. She was managed with intensive plasma exchange and hemodialysis, which failed to improve her severe acute kidney injury and other hematological manifestations of aHUS. This was further compounded by several episodes of flash pulmonary edema and the posterior reversible encephalopathy syndrome (PRES). Treatment with the monoclonal anti-C5 inhibitor, eculizumab, improved all hematological parameters with almost full renal recovery following 3.5 months of dialysis. So far, long-term use of eculizumab (> 11 months) continues to be effective and without complication. Our case illustrates the difficulty but importance of early consideration of aHUS in patients presenting with TMA. More importantly, we highlight that near-normal renal recovery may be attained with eculizumab in adults even after a long dependence on dialysis - an observation that has not been reported in the literature so far.

  19. Successful Salvage Treatment of Resistant Acute Antibody-Mediated Kidney Transplant Rejection with Eculizumab.

    PubMed

    Khan, Saif A; Al-Riyami, Dawood; Al-Mula Abed, Yasser W; Mohammed, Saja; Al-Riyami, Marwa; Al-Lawati, Nabil M

    2016-08-01

    Antibody-mediated rejection (ABMR) jeopardises short- and long-term transplant survival and remains a challenge in the field of organ transplantation. We report the first use of the anticomplement agent eculizumab in Oman in the treatment of a 61-year-old female patient with ABMR following a living unrelated kidney transplant. The patient was admitted to the Sultan Qaboos University Hospital in Muscat, Oman, in 2013 on the eighth day post-transplantation with serum creatinine (Cr) levels of 400 µmol/L which continued to rise, necessitating haemodialysis. A biopsy indicated ABMR with acute cellular rejection. No improvement was observed following standard ABMR treatment and she continued to require dialysis. Five doses of eculizumab were administered over six weeks with a subsequent dramatic improvement in renal function. The patient became dialysis-free with serum Cr levels of 119 µmol/L within four months. This case report indicates that eculizumab is a promising agent in the treatment of ABMR.

  20. Technical advances in flow cytometry-based diagnosis and monitoring of paroxysmal nocturnal hemoglobinuria.

    PubMed

    Correia, Rodolfo Patussi; Bento, Laiz Cameirão; Bortolucci, Ana Carolina Apelle; Alexandre, Anderson Marega; Vaz, Andressa da Costa; Schimidell, Daniela; Pedro, Eduardo de Carvalho; Perin, Fabricio Simões; Nozawa, Sonia Tsukasa; Mendes, Cláudio Ernesto Albers; Barroso, Rodrigo de Souza; Bacal, Nydia Strachman

    2016-01-01

    To discuss the implementation of technical advances in laboratory diagnosis and monitoring of paroxysmal nocturnal hemoglobinuria for validation of high-sensitivity flow cytometry protocols. A retrospective study based on analysis of laboratory data from 745 patient samples submitted to flow cytometry for diagnosis and/or monitoring of paroxysmal nocturnal hemoglobinuria. Implementation of technical advances reduced test costs and improved flow cytometry resolution for paroxysmal nocturnal hemoglobinuria clone detection. High-sensitivity flow cytometry allowed more sensitive determination of paroxysmal nocturnal hemoglobinuria clone type and size, particularly in samples with small clones. Discutir as melhorias técnicas no diagnóstico e no acompanhamento laboratorial de hemoglobinúria paroxística noturna para a validação da técnica de citometria de fluxo de alta sensibilidade. Estudo retrospectivo, que envolveu a análise de dados laboratoriais de 745 pacientes com hipótese diagnóstica e/ou acompanhamento de hemoglobinúria paroxística noturna por citometria de fluxo. Os avanços técnicos não só reduziram o custo do ensaio, mas também melhoraram a identificação e a resolução da citometria de fluxo para a detecção de clone hemoglobinúria paroxística noturna. A citometria de fluxo de alta sensibilidade possibilitou a identificação do tipo e do tamanho de clone de hemoglobinúria paroxística noturna, especialmente em amostras com pequeno clone.

  1. Frequency of paroxysmal nocturnal hemoglobinuria in patients attended in Belém, Pará, Brazil

    PubMed Central

    de Brito Junior, Lacy Cardoso; Cardoso, Maria do Socorro de Oliveira; Rocha, Euzamar Gaby; Anijar, Herika; Cunha, Mariana; Saraiva, João Carlos Pina

    2011-01-01

    Background Paroxysmal nocturnal hemoglobinuria is a hematological disease with complex physiopathology. It is genetically characterized by a somatic mutation in the PIG-A gene (phosphatidylinositol glycan anchor biosynthesis, class A), in which the best known antigens are DAF (decay accelerating factor or CD55) and MIRL (membrane inhibitor of reactive lysis or CD59). Objective To determine the frequency of paroxysmal nocturnal hemoglobinuria in patients attended at the HEMOPA foundation from November 2008 to July 2009. Method Thirty patients, with ages ranging from two to 79 years old and suspected of having paroxysmal nocturnal hemoglobinuria were examined. All patients were immunophenotyped by flow cytometry for the CD5, CD59, CD16 and CD45 antigens. Results Paroxysmal nocturnal hemoglobinuria was identified in nine of the thirty patients investigated. Another 3 cases had inconclusive results with CD59-negative labeling only for neutrophils. The highest frequency of paroxysmal nocturnal hemoglobinuria patients (7/9) and inconclusive cases (2/3) were between 19 years old and 48 years old, with a median of 28 years. Conclusion These results show the importance of flow cytometry to identify cases in which patients are deficient in only one antigen (CD59). PMID:23284241

  2. Case report of atypical hemolytic uremic syndrome with retinal arterial and venous occlusion treated with eculizumab

    PubMed Central

    Greenwood, Gregory T

    2015-01-01

    Atypical hemolytic uremic syndrome (aHUS) is a rare disease caused by chronic, uncontrolled activation of the alternative complement pathway, leading to thrombotic microangiopathy. Renal impairment and progression to end-stage renal disease are common in untreated patients with aHUS, and extrarenal manifestations are being increasingly characterized in the literature. Ocular involvement remains rare in aHUS. This report describes a patient with aHUS with bilateral central retinal artery and vein occlusion, vitreous hemorrhage, and blindness in addition to renal impairment. The patient’s hematologic and renal parameters and ocular manifestation improved following initiation of eculizumab therapy. PMID:26508891

  3. Management of thrombosis in paroxysmal nocturnal hemoglobinuria: a clinician’s guide

    PubMed Central

    Griffin, Morag; Munir, Talha

    2016-01-01

    Paroxysmal nocturnal haemoglobinuria (PNH), an ultra-orphan disease with a prevalence of 15.9 per million in Europe, is a life-threatening disorder, characterized by haemolysis, bone marrow failure and thrombosis. Patients with PNH prior to the availability of eculizumab had a median survival of between 10 and 22 years, with thrombosis accounting for 22–67% of deaths. 29–44% of patients had at least one thrombosis. This paper provides a clinician’s guide to the diagnosis, management and complications of PNH, with an emphasis on thrombosis. PMID:28246555

  4. BRODIFACOUM INDUCES EARLY HEMOGLOBINURIA AND LATE HEMATURIA IN RATS: NOVEL RAPID BIOMARKERS OF POISONING

    PubMed Central

    Ware, Kyle M; Feinstein, Douglas L; Rubinstein, Israel; Weinberg, Guy; Rovin, Brad H; Hebert, Lee; Muni, Navin; Cianciolo, Rachel E.; Satoskar, Anjali A; Nadasdy, Tibor; Brodsky, Sergey V

    2015-01-01

    Introduction Brodifacoum (BDF) is a superwarfarin that is used primarily as a rodenticide. There have been increasing number of reports of human cases of accidental or intentional BDF ingestion with high mortality rate. Its broad availability and high lethality suggest that BDF should be considered a potential chemical threat. Currently, there is no biomarker for early detection of BDF ingestion in humans; patients typically present with severe coagulopathy. Since we demonstrated earlier that warfarin can induce acute kidney injury with hematuria, we tested whether BDF would also lead to change in urinary biomarkers. Material and methods BDF was administered to Sprague Dawley rats via oral gavage. N-acetylcysteine (NAC) was given per os in drinking water 24 hours prior to BDF. Urinalysis was performed at different times after BDF administration. Anticoagulation and serum creatinine levels were analyzed in the blood. Results We observed that within a few hours the animals developed BDF-dose-dependent transient hemoglobinuria, which ceased within 24 hours. This was accompanied by a transient decrease in hematocrit, gross hemolysis and an increase in free hemoglobin in the serum. At later times, animals developed true hematuria with red blood cells in the urine, which was associated with BDF anticoagulation. NAC prevented early hemoglobinuria, but not late hematuria associated with BDF. Conclusions We propose that transient early hemoglobinuria (associated with oxidative stress) with consecutive late hematuria (associated with anticoagulation) are novel biomarkers of BDF poisoning and they can be used in clinical setting or in mass-casualty with BDF to identify poisoned patients. PMID:26111556

  5. Adult-onset eculizumab-resistant hemolytic uremic syndrome associated with cobalamin C deficiency.

    PubMed

    Cornec-Le Gall, Emilie; Delmas, Yahsou; De Parscau, Loïc; Doucet, Laurent; Ogier, Hélène; Benoist, Jean-François; Fremeaux-Bacchi, Véronique; Le Meur, Yannick

    2014-01-01

    A 20-year-old man was hospitalized for malignant hypertension, mechanical hemolysis, and kidney failure. Kidney biopsy confirmed glomerular and arteriolar thrombotic microangiopathy. Etiologic analyses, which included ADAMTS13 activity, stool culture, complement factor proteins (C3, C4, factor H, factor I, and MCP [membrane cofactor protein]), anti-factor H antibodies, HIV (human immunodeficiency virus) serology, and antinuclear and antiphospholipid antibodies, returned normal results. Malignant hypertension was diagnosed. Ten months later, we observed a relapse of acute kidney injury and mechanical hemolysis. Considering a diagnosis of complement dysregulation-related atypical hemolytic uremic syndrome (HUS), we began treatment with eculizumab. Despite the efficient complement blockade, the patient's kidney function continued to decline. We performed additional analyses and found that the patient's homocysteine levels were dramatically increased, with no vitamin B12 (cobalamin) or folate deficiencies. We observed very low plasma methionine levels associated with methylmalonic aciduria, which suggested cobalamin C disease. We stopped the eculizumab infusions and initiated specific treatment, which resulted in complete cessation of hemolysis. MMACHC (methylmalonic aciduria and homocystinuria type C protein) sequencing revealed compound heterozygosity for 2 causative mutations. To our knowledge, this is the first report of adult-onset cobalamin C-related HUS. Considering the wide availability and low cost of the homocysteine assay, we suggest that it be included in the diagnostic algorithm for adult patients who present with HUS. Copyright © 2013 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

  6. Neurologic involvement in atypical hemolytic uremic syndrome and successful treatment with eculizumab.

    PubMed

    Gulleroglu, Kaan; Fidan, Kibriya; Hançer, Veysel S; Bayrakci, Umut; Baskin, Esra; Soylemezoglu, Oguz

    2013-05-01

    Atypical hemolytic uremic syndrome (aHUS) is associated with defective regulation of the complement pathway. Neurological involvement is the most common extrarenal complication and represents a major cause of mortality and morbidity. Two girls aged 11 and 6 years, respectively, developed aHUS and were treated immediately with plasma exchange (PE) and fresh frozen plasma infusion (PI). Although initial improvement in renal function was seen in both cases, the first patient showed progressing thrombotic microangiopathy (TMA) despite daily PE, and neurological manifestations (seizures, vision loss, loss of balance, and confusion) developed after 1 month. The second patient developed cerebral TMA (seizures, vision loss, and nystagmus) 6 days after initial presentation and remained unresponsive to PE/PI. Neurological symptoms were similar in both patients, even though they had different complement protein mutations. Treatment with eculizumab achieved complete control of neurological symptoms within 24 h and gradually normalized hematological and renal parameters in both children. Based on our two cases, we conclude that eculizumab is a rapid-acting, effective, and life-saving treatment for pediatric patients with aHUS and severe neurological involvement, which works by inhibiting complement-mediated TMA in the kidney and other organs, such as the brain.

  7. Atypical Hemolytic Uremic Syndrome Secondary to Lupus Nephritis, Responsive to Eculizumab

    PubMed Central

    Raufi, Alexander G.; Scott, Shruti; Darwish, Omar; Harley, Kevin; Kahlon, Kanwarpal; Desai, Sheetal; Lu, Yuxin; Tran, Minh-Ha

    2016-01-01

    Among the spectrum of disease manifestations associated with systemic lupus erythematosus, lupus nephritis is particularly concerning due to the potential for renal failure. This autoimmune attack may not, however, be limited to the kidney and is increasingly being recognized as a trigger for atypical Hemolytic Uremic Syndrome (aHUS). Atypical HUS falls under the spectrum of the thrombotic microangiopathies (TMAs) – a group of disorders characterized by microangiopathic hemolytic anemia, thrombocytopenia, and end organ damage. Although plasma exchange is considered first-line therapy for thrombotic thrombocytopenic purpura – a TMA classically associated with autoimmune depletion of ADAMTS-13 – aHUS demonstrates less reliable responsiveness to this modality. Instead, use of the late complement inhibitor Eculizumab has emerged as an effective modality for the management of such patients. Diagnosis of aHUS, however, is largely clinically based, relying heavily upon a multidisciplinary approach. Herein we present the case of a patient with atypical HUS successfully treated with Eculizumab in the setting of Class IV-G (A) lupus nephritis and hypocomplementemia. PMID:27781079

  8. Atypical Hemolytic Uremic Syndrome and Chronic Ulcerative Colitis Treated with Eculizumab

    PubMed Central

    Webb, Tennille N.; Griffiths, Heidi; Miyashita, Yosuke; Bhatt, Riha; Jaffe, Ronald; Moritz, Michael; Hofer, Johannes; Swiatecka-Urban, Agnieszka

    2016-01-01

    Background Hemolytic-uremic syndrome (HUS) presents with hemolytic anemia, thrombocytopenia, and thrombotic microangiopathy of the kidney and usually results from Shiga-toxin induced activation of the alternative complement pathway. Gastroenteritis is a common feature of the Shiga-toxin producing Escherichia coli HUS, referred to as STEC-HUS. An inherited or acquired complement dysregulation may lead to HUS referred to as non-STEC or atypical (a)HUS. Although gastroenteritis is not a common presentation of aHUS, some patients develop ischemic colitis and may be misdiagnosed as acute appendicitis or acute ulcerative colitis (UC). Case Diagnosis –Treatment We present a patient with low circulating complement (C) 3 levels who developed aHUS in the course of chronic active UC. Resolution of renal and gastrointestinal manifestations in response to treatment with eculizumab, a humanized monoclonal antibody against terminal C5 protein suggests the role of alternative complement in the pathogenesis of both, aHUS and UC. Conclusion This case illustrates that dysregulation of the alternative complement pathway may manifest in other organs besides the kidney and that the circulating C3 levels do not correlate with the disease activity or the clinical response to eculizumab. PMID:27135055

  9. Efficacy and safety of eculizumab in atypical hemolytic uremic syndrome from 2-year extensions of phase 2 studies.

    PubMed

    Licht, Christoph; Greenbaum, Larry A; Muus, Petra; Babu, Sunil; Bedrosian, Camille L; Cohen, David J; Delmas, Yahsou; Douglas, Kenneth; Furman, Richard R; Gaber, Osama A; Goodship, Timothy; Herthelius, Maria; Hourmant, Maryvonne; Legendre, Christophe M; Remuzzi, Giuseppe; Sheerin, Neil; Trivelli, Antonella; Loirat, Chantal

    2015-05-01

    Atypical hemolytic uremic syndrome (aHUS) is a rare, possibly life-threatening disease characterized by platelet activation, hemolysis and thrombotic microangiopathy (TMA) leading to renal and other end-organ damage. We originally conducted two phase 2 studies (26 weeks and 1 year) evaluating eculizumab, a terminal complement inhibitor, in patients with progressing TMA (trial 1) and those with long duration of aHUS and chronic kidney disease (trial 2). The current analysis assessed outcomes after 2 years (median eculizumab exposure 100 and 114 weeks, respectively). At all scheduled time points, eculizumab inhibited terminal complement activity. In trial 1 with 17 patients, the platelet count was significantly improved from baseline, and hematologic normalization was achieved in 13 patients at week 26, and in 15 patients at both 1 and 2 years. The estimated glomerular filtration rate (eGFR) was significantly improved compared with baseline and year 1. In trial 2 with 20 patients, TMA event-free status was achieved by 16 patients at week 26, 17 patients at year 1, and 19 patients at year 2. Criteria for hematologic normalization were met by 18 patients at each time point. Improvement of 15 ml/min per 1.73 m(2) or more in eGFR was achieved by 1 patient at week 26, 3 patients at 1 year, and 8 patients at 2 years. The mean change in eGFR was not significant compared with baseline, week 26, or year 1. Eculizumab was well tolerated, with no new safety concerns or meningococcal infections. Thus, a 2-year analysis found that the earlier clinical benefits achieved by eculizumab treatment of aHUS were maintained at 2 years of follow-up.

  10. Complement-mediated thrombotic microangiopathy secondary to sepsis-induced disseminated intravascular coagulation successfully treated with eculizumab

    PubMed Central

    Abe, Tomohiro; Sasaki, Akira; Ueda, Taichiro; Miyakawa, Yoshitaka; Ochiai, Hidenobu

    2017-01-01

    Abstract Secondary thrombotic microangiopathies (TMAs) are induced by several underlying conditions; most are resolved by treating background disease. Eculizumab is a human monoclonal antibody that blocks the final stage of the complement system and effectively treats atypical hemolytic uremic syndrome (aHUS). In this report, we present a patient with TMA secondary to sepsis- induced coagulopathy, who was successfully treated with eculizumab. A 44-year-old woman, who had no special medical history or familial history of TMAs, was admitted on suspicion of septic shock. Physical examination revealed gangrene on her soles. Blood tests revealed a decreased platelet count, disseminated intravascular coagulation (DIC), renal dysfunction, hemolysis, and infection. Although the coagulation disorder improved with intensive care, the low platelet count, elevated lactate dehydrogenase levels, and renal dysfunction persisted. Our investigations subsequently excluded thrombotic thrombocytopenic purpura and Shiga toxin-producing Escherichia coli-induced HUS. Plasma exchange only improved lactate dehydrogenase levels. We clinically diagnosed this case as atypical HUS and started eculizumab treatment. The patient's platelet count increased, her renal dysfunction improved, and the gangrene on her feet was ameliorated. The patient was discharged without maintenance dialysis therapy after approximately 3 months. Subsequent tests revealed elevated serum levels of soluble C5b-9, and genetic testing revealed compound heterozygous c.184G > A (Val62Ile) and c.1204T > C (Tyr402His) single-nucleotide polymorphisms in complement factor H. We encountered a case of complement-mediated TMA accompanied by DIC, which was successfully treated with eculizumab. Further studies are necessary to support the optimal use of eculizumab for TMA with background diseases. PMID:28178155

  11. Complement-mediated thrombotic microangiopathy secondary to sepsis-induced disseminated intravascular coagulation successfully treated with eculizumab: A case report.

    PubMed

    Abe, Tomohiro; Sasaki, Akira; Ueda, Taichiro; Miyakawa, Yoshitaka; Ochiai, Hidenobu

    2017-02-01

    Secondary thrombotic microangiopathies (TMAs) are induced by several underlying conditions; most are resolved by treating background disease. Eculizumab is a human monoclonal antibody that blocks the final stage of the complement system and effectively treats atypical hemolytic uremic syndrome (aHUS). In this report, we present a patient with TMA secondary to sepsis- induced coagulopathy, who was successfully treated with eculizumab.A 44-year-old woman, who had no special medical history or familial history of TMAs, was admitted on suspicion of septic shock. Physical examination revealed gangrene on her soles. Blood tests revealed a decreased platelet count, disseminated intravascular coagulation (DIC), renal dysfunction, hemolysis, and infection. Although the coagulation disorder improved with intensive care, the low platelet count, elevated lactate dehydrogenase levels, and renal dysfunction persisted. Our investigations subsequently excluded thrombotic thrombocytopenic purpura and Shiga toxin-producing Escherichia coli-induced HUS. Plasma exchange only improved lactate dehydrogenase levels. We clinically diagnosed this case as atypical HUS and started eculizumab treatment. The patient's platelet count increased, her renal dysfunction improved, and the gangrene on her feet was ameliorated. The patient was discharged without maintenance dialysis therapy after approximately 3 months. Subsequent tests revealed elevated serum levels of soluble C5b-9, and genetic testing revealed compound heterozygous c.184G > A (Val62Ile) and c.1204T > C (Tyr402His) single-nucleotide polymorphisms in complement factor H.We encountered a case of complement-mediated TMA accompanied by DIC, which was successfully treated with eculizumab. Further studies are necessary to support the optimal use of eculizumab for TMA with background diseases.

  12. Diagnostic screening of paroxysmal nocturnal hemoglobinuria: Prospective multicentric evaluation of the current medical indications.

    PubMed

    Morado, Marta; Freire Sandes, Alex; Colado, Enrique; Subirá, Dolores; Isusi, Paloma; Soledad Noya, María; Belén Vidriales, María; Sempere, Amparo; Ángel Díaz, José; Minguela, Alfredo; Álvarez, Beatriz; Serrano, Cristina; Caballero, Teresa; Rey, Mercedes; Pérez Corral, Ana; Cristina Fernández Jiménez, María; Magro, Elena; Lemes, Angelina; Benavente, Celina; Bañas, Helena; Merino, Juana; Castejon, Celine; Gutierrez, Olivier; Rabasa, Pilar; Vescosi Gonçalves, Matheus; Perez-Andres, Martin; Orfao, Alberto

    2017-09-01

    Although consensus guidelines have been proposed in 2010 for the diagnostic screening of paroxysmal nocturnal hemoglobinuria (PNH) by flow cytometry (FCM), so far no study has investigated the efficiency of such medical indications in multicentric vs. reference laboratory settings. Here we evaluate the efficiency of consensus medical indications for PNH testing in 3,938 peripheral blood samples submitted to FCM testing in 24 laboratories in Spain and one reference center in Brazil. Overall, diagnostic screening based on consensus medical indications was highly efficient (14% of PNH(+) samples) both in the multicenter setting in Spain (10%) and the reference laboratory in Brazil (16%). The highest frequency of PNH(+) cases was observed among patients screened because of bone marrow (BM) failure syndrome (33%), particularly among those with aplastic anemia (AA; 45%) and to a less extent also a myelodysplastic syndrome (MDS; 10%). Among the other individuals studied, the most efficient medical indications for PNH screening included: hemolytic anemia (19%), hemoglobinuria (48%) and unexplained cytopenias (9%). In contrast, only a minor fraction of the patients who had been submitted for PNH testing because of unexplained thrombosis in the absence of cytopenia, were positive (0.4%). In summary, our results demonstrate that the current medical indications for PNH screening by FCM are highly efficient, although improved screening algorithms are needed for patients presenting with thrombosis and normal blood cell counts. © 2016 International Clinical Cytometry Society. © 2016 International Clinical Cytometry Society.

  13. Acquired thrombotic thrombocytopenic purpura and atypical hemolytic uremic syndrome successfully treated with eculizumab

    PubMed Central

    Cottler-Fox, Michele; Motwani, Pooja

    2017-01-01

    Acquired idiopathic thrombotic thrombocytopenic purpura is a life-threatening disease with a mortality of up to 90%, if not promptly recognized and treated. We report a 64-year-old woman with this condition who presented with left-sided weakness and seizure-like activity preceded by headache and easy bruising. She did not achieve optimal response to plasma exchange, corticosteroids, rituximab, and vincristine. We initiated treatment with eculizumab, following which she had durable remission that continued for 30 months after discontinuation of the drug. We later found that our patient has homozygous deletion in two closely related genes, complement factor H–related 1 and complement factor H–related 3. PMID:28405075

  14. Rescue therapy with eculizumab in a transplant recipient with atypical haemolytic-uraemic syndrome

    PubMed Central

    Durán, Carlos E.; Blasco, Miquel; Maduell, Francisco

    2012-01-01

    Haemolytic–uraemic syndrome is a clinical syndrome characterized by thrombocytopaenia, non-autoimmune haemolytic anaemia and renal impairment. Pathological alterations in kidney samples show thrombotic microangiopathy. The underlying pathogenesis is endothelial cell injury with thrombotic occlusion of the arterioles and capillaries. A variety of causes have been identified, associated with infection of Escherichia coli O157:H7, environmental factors as immunosuppressive drugs and genetic deficiencies in complement regulatory factors. The latter is called atypical haemolytic–uraemic syndrome (aHUS). Here, we present a patient with severe aHUS with complement factor H deficiency triggered by cocaine use and recurrence after kidney transplantation. The patient restarted haemodialysis for severe renal insufficiency and anti-C5 antibody eculizumab was used as salvage treatment with progressive recovery of graft function and suppression of dialysis. PMID:26069742

  15. Belatacept and Eculizumab for Treatment of Calcineurin Inhibitor-induced Thrombotic Microangiopathy After Kidney Transplantation: Case Report.

    PubMed

    Merola, J; Yoo, P S; Schaub, J; Smith, J D; Rodriguez-Davalos, M I; Tichy, E; Mulligan, D C; Asch, W; Formica, R; Kashgarian, M; Kulkarni, S

    2016-11-01

    Thrombotic microangiopathy (TMA) after kidney transplantation is an uncommon and challenging cause of graft dysfunction and is associated with early graft loss. An idiosyncratic endothelial reaction to calcineurin inhibitors (CNIs) has been implicated as a frequent cause of TMA. This reaction is marked by uncontrolled activation of complement and subsequent cellular destruction. Usual therapy consists of withdrawal of the inciting drug and plasmapheresis to minimize levels of circulating complement. Recently, eculizumab, a monoclonal antibody to complement component C5, has been used for the treatment of atypical hemolytic uremic syndrome. Belatacept, an inhibitor of T cell costimulatory protein CTLA-4 has been used in immunosuppression strategies aimed at minimization of CNI. Here we report the first case of treatment of CNI-associated TMA/hemolytic uremic syndrome with withdrawal of tacrolimus and initiation of both belatacept and eculizumab. The case describes a favorable clinical course for both graft and patient, and is accompanied by a review of the literature.

  16. Eculizumab for Treatment of Refractory Antibody-Mediated Rejection in Kidney Transplant Patients: A Single-Center Experience.

    PubMed

    Yelken, B; Arpalı, E; Görcin, S; Kocak, B; Karatas, C; Demiralp, E; Turkmen, A

    2015-01-01

    Antibody-mediated rejection (AMR) is responsible for up to 20%-30% of acute rejection episodes after kidney transplantation. In several cases, conventional therapies including plasmapheresis, intravenous immunoglobulin, and anti-CD20 therapy can resolve AMR successfully. But in some cases the load of immunoglobulins that can activate complement cascade may submerge the routine desensitization therapy and result in the formation of membrane attack complexes. Eculizumab, a monoclonal antibody against C5, was reported to be an option in cases with severe AMR that are resistant to conventional therapy. Here, we present 8 cases that were resistant to conventional therapy and in which eculizumab was given as a salvage treatment. Given the bad prognosis for renal transplants displaying acute injury progressing rapidly to cortical necrosis on the biopsy, the prompt use of eculizumab could have the advantage of immediate effects by stopping cellular injury. This can provide a therapeutic window to allow conventional treatment modalities to be effective and prevent early graft loss.

  17. Assembly and deacetylation of N-acetylglucosaminyl-plasmanylinositol in normal and affected paroxysmal nocturnal hemoglobinuria cells

    SciTech Connect

    Hirose, Shinichi; Ravi, Lakshmeswari; Medof, M.D. ); Hazra, S.V. )

    1991-05-01

    Decay-accelerating factor (DAF) is anchored in cell membranes by a glycosyl-plasmanylinositol (GPI) moiety that is transferred to it en bloc in the rough endoplasmic reticulum. To analyze the biochemical reactions involved in preassembly of this structure, a human hematopoietic cell-free system was employed. Incubation of cell extracts with UDP-({sup 3}H)GlcNAc and butanol partitioning of reaction mixtures yielded two products similar in TLC mobility to intermediates described in Trypanoxoma brucei. Both species were sensitive to Bacillus thuringiensis phosphatidylinositol-specific phospholipase C, indicative of association of ({sup 3}H)GlcNAc label with a plasmanylinositol-containing acceptor. Kinetic and pulse-chase experiments indicated that the slower-migrating species was a product of the faster and that it, but not the faster, was sensitive to both GPI-specific phospholipase D and nitrous acid deamination, consistent with conversion of GlcNAc- to GlcN-plasmanylinositol. Lysates of normal and of affected blood leukocytes from two paroxysmal nocturnal hemoglobinuria (PNH) patients supported assembly of the two intermediates within 1 min. Thus, the initial enzymes mediating human GPI-anchor assembly are GlcNAc-plasmanylinositol transferase and GlcNAc-plasmanylinositol deacetylase, their substrates contain plasmanylinositols, and the products of their activities are normal in affected PNH cells.

  18. Development of paroxysmal nocturnal hemoglobinuria in CALR-positive myeloproliferative neoplasm

    PubMed Central

    Fraiman, Yarden S; Cuka, Nathan; Batista, Denise; Vuica-Ross, Milena; Moliterno, Alison R

    2016-01-01

    Paroxysmal nocturnal hemoglobinuria (PNH), a disease characterized by intravascular hemolysis, thrombosis, and bone marrow failure, is associated with mutations in the PIG-A gene, resulting in a deficiency of glycosylphosphatidylinositol-anchored proteins. Many hypotheses have been posed as to whether PNH and PIG-A mutations result in an intrinsic survival benefit of CD55−/CD59− cells or an extrinsic permissive environment that allows for their clonal expansion within the bone marrow compartment. Recent data have identified the concurrence of PIG-A mutations with additional genetic mutations associated with myeloproliferative disorders, suggesting that some presentations of PNH are the result of a stepwise progression of genetic mutations similar to other myelodysplastic or myeloproliferative syndromes. We report for the first time in the literature the development of clinically significant PNH in a patient with JAK2V617F-negative, CALR-positive essential thrombocythemia, providing further support to the hypothesis that the development of PNH is associated with the accumulation of multiple genetic mutations that create an intrinsic survival benefit for clonal expansion. This case study additionally highlights the utility of genomic testing in diagnosis and the understanding of disease progression in the clinical setting. PMID:27313483

  19. Flow cytometric analysis of glycosylphosphatidyl-inositol-anchored proteins to assess paroxysmal nocturnal hemoglobinuria clone size.

    PubMed

    Piedras, J; López-Karpovitch, X

    2000-08-15

    Paroxysmal nocturnal hemoglobinuria (PNH) is characterized by total or partial deficiency of membrane proteins anchored to the cell surface through a glycosylphosphatidyl-inositol (GPI) moiety. The relationship between the size of the PNH clone, determined by the expression of GPI-anchored proteins (AP; CD14, CD48, CD55, CD59, and CD66b) on erythrocytes, lymphocytes, monocytes, and granulocytes using forward and side scatter analysis, and severity of the disease was evaluated in 19 PNH patients. CD55 antigen expression did not delineate abnormal erythrocytes as well as did anti-CD59. The proportion of monocytes deficient in CD55, CD59, CD48, and CD14 (48-97%) and of granulocytes deficient in CD55, CD59, and CD66b (60-99%) was greater than the proportion of erythrocytes deficient in CD59 (24-95%) and the proportion of lymphocytes deficient in CD55 and CD59 (30-98%). There were no significant correlations among reticulocyte, leukocyte, and platelet counts and GPI-AP-deficient immunophenotypes in red and white blood cells. However, high coefficients of determination were seen between hemoglobin levels and granulocytes deficient in CD59 (r(2) = 0.76), CD55 (r(2) = 0.74), and CD66b (r(2) = 0.74) antigens and between hemoglobin and monocytes deficient in CD55 (r(2) = 0.73), CD59 (r(2) = 0.80), and CD14 (r(2) = 0.75) antigens. These results are interpreted as indicating that the size of PNH clone is better assessed by immunophenotypic analysis of monocytes and granulocytes rather than of lymphocytes and erythrocytes. Copyright 2000 Wiley-Liss, Inc.

  20. A comparative analysis of clinical characteristics of patients with paroxysmal nocturnal hemoglobinuria between Asia and Europe/America.

    PubMed

    Yu, Fan; Du, Yali; Han, Bing

    2016-06-01

    To accurately analyze the clinical characteristics of paroxysmal nocturnal hemoglobinuria (PNH) in different ethnic backgrounds, we retrieved all retrospective studies on clinical characteristics of PNH with a median follow-up period >60 months published after 2000, analyzed the clinical characteristics of PNH patients in Asia and European/America, and statistically compared enumeration data in these studies. We included 1665 patients in this analysis. The proportion of female patients in Asia was significantly lower than that in Europe/America (P = 0.000). Incidence rates of hemoglobinuria and thromboembolism in Asia were significantly lower than in Europe/America (both P values were 0.000). Within the subgroups of patients with thromboembolism, Asian patients had a higher proportion of arterial thrombosis while Western patients had a higher proportion of abdominal venous thrombosis. Bone marrow failure was not clearly defined in most studies. The proportion of patients with pancytopenia was higher in China than in France (P = 0.048). The total death rates were similar in both ethnic groups (P > 0.05). In Europe/America the major cause of death was thromboembolism and in Asian countries was serious infections. Differences in population characteristics of PNH patients among different ethnic groups indicate the possibility of differential pathogenesis and may be informative for treatment decisions.

  1. Synthesis of mannosylglucosaminylinositol phospholipids in normal but not paroxysmal nocturnal hemoglobinuria cells.

    PubMed

    Hirose, S; Ravi, L; Prince, G M; Rosenfeld, M G; Silber, R; Andresen, S W; Hazra, S V; Medof, M E

    1992-07-01

    To identify mannosyl (Man)-containing intermediates of the human glycoinositol phospholipid (GPI) anchor pathway and examine their expression in paroxysmal nocturnal hemoglobinuria (PNH), mannolipid products deriving from in vitro guanosine diphosphate [3H]Man labeling of HeLa cell microsomes were characterized. The defined GPI species were correlated with products deriving from in vivo [3H]Man labeling of normal and (GPI-anchor defective) affected leukocytes. In vitro analyses in HeLa cells showed dolichol-phosphoryl (Dol-P)-[3H]Man and a spectrum of [3H]Man lipids exhibiting TLC mobilities approximating those of Trypanosoma brucei (Tryp) GPI precursors. Iatrobead HPLC separations and partial characterizations of the major isolated [3H]Man species (designated H1-H8) showed that all but H1 (Dol-P-Man) were sensitive to HNO2 deamination and serum GPI-specific phospholipase D digestion but were resistant to phosphatidylinositol-specific phospholipase C digestion unless previously deacylated with mild alkali. [3H]Man label in H3, H4, and H6 but not in H5 or H7 was efficiently released into the aqueous phase by jack bean alpha-mannosidase digestion. BioGel P-4 and AX-5 sizing of the dephosphorylated core glycan fragments of H6 and H7 gave values that coincided precisely with the corresponding glycan fragments from the fully assembled Tryp anchor donor A' (P2). Affected leukocytes from four patients with PNH supported formation of GlcNAc- and GlcN-PI but all failed to express H6 and H7 as well as H8 and two showed complete absence of earlier Man-containing intermediates. These findings argue that human intracellular GPI mannolipids are built on acylated inositol phospholipids, that H6 and H7 contain differentially phosphoethanolamine-substituted Man3-GlcN-inositol cores, and that PNH cells are defective in conversion of GlcN-PI into these more mature mannolipid structures.

  2. 36-Year-Old Female with Catastrophic Antiphospholipid Syndrome Treated with Eculizumab: A Case Report and Review of Literature

    PubMed Central

    Strakhan, Marianna; Galeas, Nahun; Bakirhan, Kamila

    2014-01-01

    Catastrophic antiphospholipid syndrome (CAPS) is a rare but potentially life-threatening condition characterized by diffuse vascular thrombosis, leading to multiple organ failure developing over a short period of time in the presence of positive antiphospholipid antibodies (aPL). CAPS is a severe form of antiphospholipid syndrome, developing in about 1% of cases of classic antiphospholipid syndrome, manifesting as microangiopathy, affecting small vessels of multiple organs. It is acute in onset, with majority of cases developing thrombocytopenia and less frequently hemolytic anemia and disseminated intravascular coagulation. Lupus anticoagulant and anticardiolipin antibodies have been reported as predominant antibodies associated with CAPS. Treatment options often utilized in CAPS include anticoagulation, steroids, plasma exchange, cyclophosphamide therapy, and intravenous immunoglobulin therapy. Even though the reported incidence of this condition is considered to be low, the mortality rate is approaching 50%. The high rate of mortality should warrant greater awareness among clinicians for timely diagnosis and treatment of this life-threatening condition. Studies have shown that complement activation plays a key role in the pathogenesis of aPL mediated thrombosis in CAPS. We report a case of a 36-year-old female admitted with clinical and laboratory findings consistent with CAPS successfully treated with eculizumab, a terminal complement inhibitor. PMID:25389502

  3. 36-year-old female with catastrophic antiphospholipid syndrome treated with eculizumab: a case report and review of literature.

    PubMed

    Strakhan, Marianna; Hurtado-Sbordoni, Mariana; Galeas, Nahun; Bakirhan, Kamila; Alexis, Karenza; Elrafei, Tarek

    2014-01-01

    Catastrophic antiphospholipid syndrome (CAPS) is a rare but potentially life-threatening condition characterized by diffuse vascular thrombosis, leading to multiple organ failure developing over a short period of time in the presence of positive antiphospholipid antibodies (aPL). CAPS is a severe form of antiphospholipid syndrome, developing in about 1% of cases of classic antiphospholipid syndrome, manifesting as microangiopathy, affecting small vessels of multiple organs. It is acute in onset, with majority of cases developing thrombocytopenia and less frequently hemolytic anemia and disseminated intravascular coagulation. Lupus anticoagulant and anticardiolipin antibodies have been reported as predominant antibodies associated with CAPS. Treatment options often utilized in CAPS include anticoagulation, steroids, plasma exchange, cyclophosphamide therapy, and intravenous immunoglobulin therapy. Even though the reported incidence of this condition is considered to be low, the mortality rate is approaching 50%. The high rate of mortality should warrant greater awareness among clinicians for timely diagnosis and treatment of this life-threatening condition. Studies have shown that complement activation plays a key role in the pathogenesis of aPL mediated thrombosis in CAPS. We report a case of a 36-year-old female admitted with clinical and laboratory findings consistent with CAPS successfully treated with eculizumab, a terminal complement inhibitor.

  4. Multiparameter FLAER-based flow cytometry for screening of paroxysmal nocturnal hemoglobinuria enhances detection rates in patients with aplastic anemia.

    PubMed

    Sachdeva, Man Updesh Singh; Varma, Neelam; Chandra, Dinesh; Bose, Parveen; Malhotra, Pankaj; Varma, Subhash

    2015-05-01

    Flow cytometry is the gold standard methodology for screening of paroxysmal nocturnal hemoglobinuria. In the last few years, proaerolysin conjugated with fluorescein (FLAER) has become an important component of antibody panel used for the detection of paroxysmal nocturnal hemoglobinuria (PNH) clone. This study aimed to compare PNH clone detection by flow cytometry in the pre-FLAER era versus the FLAER era. This was a retrospective analysis of 4 years and included 1004 individuals screened for PNH clone, either presenting as hemolytic anemia or as aplastic anemia. In the pre-FLAER time period, the RBCs and neutrophils were screened with antibodies against CD55 and CD59. With the introduction of FLAER, neutrophils were screened with FLAER/CD24/CD15 and monocytes with FLAER/CD14/CD33 combination. A comparative analysis was done for detection of PNH clone in aplastic anemia patients versus non-aplastic anemia patients, as well as between pre-FLAER and FLAER era. Out of a total of 1004 individuals, 59 (5.8%) were detected to have PNH clone positivity. The frequency of PNH clone detected in aplastic anemia and non-aplastic anemia groups was 12.02 and 3.36%, respectively. The detection rate of PNH clone increased from 4.5% (32/711) in the pre-FLAER era to 9.2% (27/293) with the introduction of FLAER. However, this increase could be attributed to increased detection of PNH clone in the aplastic anemia group, which showed a significant increase from 8.3 to 18.2% after use of FLAER. In the non-aplastic group, PNH clone was detected with similar frequencies before and after use of FLAER (3.2 versus 3.8%, respectively). Mean PNH clone size was lower in the aplastic anemia group when compared with the non-aplastic group. RBCs always showed a lower clone size than neutrophils. PNH clone on neutrophils and monocytes was however similar. Inclusion of FLAER increases the sensitivity of the test which is especially useful in picking up small PNH clones in patients of aplastic anemia.

  5. The study on RBC characteristic in paroxysmal nocturnal hemoglobinuria (PNH) patients using common path interferometric quantitative phase microscopy

    NASA Astrophysics Data System (ADS)

    Park, Byung Jun; Won, Youngjae; Kim, Byungyeon; Lee, Seungrag

    2016-03-01

    We have studied the RBC membrane properties between a normal RBC and a RBC in Paroxysrnal nocturnal hemoglobinuria (PNH) patient using common path interferometric quantitative phase microscopy (CPIQPM). CPIQPM system has provided the subnanometer optical path length sensitivity on a millisecond. We have measured the dynamic thickness fluctuations of a normal RBC membrane and a RBC membrane in PNH patient over the whole cell surface with CPIQPM. PNH is a rare and serious disease of blood featured by destruction of red blood cells (RBCs). This destruction happens since RBCs show the defect of protein which protects RBCs from the immune system. We have applied CPIQPM to study the characteristic of RBC membrane in PNH patient. We have shown the morphological shape, volume, and projected surface for both different RBC types. The results have showed both RBCs had the similar shape with donut, but membrane fluctuations in PNH patient was shown to reveal the difference of temporal properties compared with a normal RBC. In order to demonstrate the practical tool of the CPIQPM technique, we have also obtained the time series thickness fluctuation outside a cell.

  6. A Novel Marker for Screening Paroxysmal Nocturnal Hemoglobinuria Using Routine Complete Blood Count and Cell Population Data

    PubMed Central

    Kahng, Jimin; Kim, Yonggoo; Kim, Jung Ok; Koh, Kwangsang; Lee, Jong Wook

    2015-01-01

    Background Final diagnosis of paroxysmal nocturnal hemoglobinuria (PNH) may take years demanding a quick diagnosis measure. We used the facts that PNH cells are damaged in acid, and reagents for measuring reticulocytes in Coulter DxH800 (Beckman Coulter, USA) are weakly acidic and hypotonic, to create a new PNH screening marker. Methods We analyzed 979 complete blood counts (CBC) data from 963 patients including 57 data from 44 PNH patients. Standard criteria for PNH assay for population selection were followed: flow cytometry for CD55 and CD59 on red blood cells (RBCs) to a detection level of 1%; and fluorescent aerolysin, CD24 and CD15 in granulocytes to 0.1%. Twenty-four PNH minor clone-positive samples (minor-PNH+) were taken, in which the clone population was <5% of RBCs and/or granulocytes. Excluding PNH and minor-PNH+ patients, the population was divided into anemia, malignancy, infection, and normal groups. Parameters exhibiting a distinct demarcation between PNH and non-PNH groups were identified, and each parameter cutoff value was sought that includes the maximum [minimum] number of PNH [non-PNH] patients. Results Cutoff values for 5 selected CBC parameters (MRV, RDWR, MSCV, MN-AL2-NRET, and IRF) were determined. Positive rates were: PNH (86.0%), minor-PNH+ (33.3%), others (5.0%), anemia (13.4%), malignancy (5.3%), infection (3.7%), normal (0.0%); within anemia group, aplastic anemia (40.0%), immune hemolytic anemia (11.1%), iron deficiency anemia (1.6%). Sensitivity (86.0%), specificity (95.0%), PPV (52.1%), and NPV (99.1%) were achieved in PNH screening. Conclusion A new PNH screening marker is proposed with 95% specificity and 86% sensitivity. The flag identifies PNH patients, reducing time to final diagnosis by flow cytometry. PMID:25553278

  7. [The variation and clinical significance of paroxysmal nocturnal hemoglobinuria clone in patients with aplastic anemia before and after immunosuppressive therapy].

    PubMed

    Sun, Ying-xin; Zhu, Ming-qing; He, Guang-sheng; Wang, Xiu-li; Fang, Bao-zhi; Lu, Cong; Liu, Zhen-zhen; Wu, Qian; Yang, Yong; Wu, De-pei; Sun, Ai-ning

    2013-07-01

    To evaluate the evolution of paroxysmal nocturnal hemoglobinuria (PNH) clone and its clinical significance before and after immunosuppressive therapy (IST) in patients with aplastic anemia (AA). A total of 186 patients diagnosed as AA were enrolled in this study. Among them, 55 patients were diagnosed as severe AA (SAA) and treated with cyclosporine (CsA) plus anti-thymocyte globulin (ATG), 131 were diagnosed as non SAA (NSAA) and treated with CsA alone. All patients were screened for PNH clone by flow cytometry before treatment and followed up for 18-76 months, with a median time of 22 months. Positive PNH clones were detected in 10 SAA (18.9%) patients, significantly more than that of NSAA group [9 patients (7.4%), t = 5.041, P = 0.025]. The proportions of PNH clones in SAA group at 6, 12, 24 and > 24 months were 13.38%, 14.88%, 20.00% and 18.85%, respectively, also significantly higher than those of NSAA patients (5.67%, 5.31%, 5.47% and 9.08%, all P values < 0.05). Clinical response rates were comparable in both ATG+CsA or CsA alone groups no matter PNH clone was positive or negative. PNH clone are detectable in AA patients either treated with ATG plus CsA or CsA alone, and more significant by ATG plus CsA. Whether PNH clone occurred before or after IST does not affect the therapeutic efficacy.

  8. CALUTRON RECEIVER

    DOEpatents

    Barnes, S.W.

    1959-06-16

    An improved receiver and receiver mount for calutrons are described. The receiver can be manipulated from outside the tank by a single control to position it with respect to the beam. A door can be operated exteriorly also to prevent undesired portions of the beam from entering the receiver. The receiver has an improved pocket which is more selective in the ions collected. (T.R.H.)

  9. CALUTRON RECEIVER

    DOEpatents

    Brunk, W.O.

    1959-09-29

    A description is given for an improved calutron receiver having a face plate lying at an angle to the direction of the entering ion beams but having an opening, the plane of which is substantially perpendicular to that of the entering ion beams. By so positioning the opening in the receiver, the effective area through which the desired material may enter the receiver is increased, and at the same time the effective area through which containattng material may enter the receiver is reduced.

  10. CALUTRON RECEIVER

    DOEpatents

    York, H.F.

    1959-07-01

    A receiver construction is presented for calutrons having two or more ion sources and an individual receiver unit for each source. Design requirements dictate that the face plate defining the receiver entrance slots be placed at an angle to the approaching beam, which means that ions striking the face plate are likely to be scattcred into the entrance slots of other receivers. According to the present invention, the face plate has a surface provided with parallel ridges so disposed that one side only of each ridge's exposed directly to the ion beam. The scattered ions are directed away from adjacent receivers by the ridges on the lace plate.

  11. Successful Treatment of Ascites using a DenverⓇ Peritoneovenous Shunt in a Patient with Paroxysmal Nocturnal Hemoglobinuria and Budd-Chiari syndrome

    PubMed Central

    Kogiso, Tomomi; Hashimoto, Etsuko; Ito, Taito; Hara, Toshifumi; Ikarashi, Yuichi; Kodama, Kazuhisa; Taniai, Makiko; Torii, Nobuyuki; Yoshinaga, Kentaro; Morita, Satoru; Takahashi, Yutaka; Tanaka, Junji; Sakai, Shuji; Yamamoto, Masakazu; Tokushige, Katsutoshi

    2016-01-01

    A 56-year-old man was diagnosed with aplastic anemia and paroxysmal nocturnal hemoglobinuria at 43 years of age and treatment with cyclosporin A was started. Liver cirrhosis, ascites, and thrombus in the hepatic veins were found at 56 years of age and Budd-Chiari syndrome (BCS) was diagnosed according to angiography findings. He was treated with diuretics and paracentesis was performed several times, but with limited efficacy. A DenverⓇ peritoneovenous shunt (PVS) was inserted into the right jugular vein; his ascites and renal function improved immediately and his general condition has remained good for 12 months since starting the above treatment regimen. A PVS is a treatment option for ascites due to BCS. PMID:27746432

  12. CALUTRON RECEIVERS

    DOEpatents

    Schmidt, F.H.; Stone, K.F.

    1958-09-01

    S>This patent relates to improvements in calutron devices and, more specifically, describes a receiver fer collecting the ion curreot after it is formed into a beam of non-homogeneous isotropic cross-section. The invention embodies a calutron receiver having an ion receiving pocket for separately collecting and retaining ions traveling in a selected portion of the ion beam and anelectrode for intercepting ions traveling in another selected pontion of the ion beam. The electrode is disposed so as to fix the limit of one side of the pontion of the ion beam admitted iato the ion receiving pocket.

  13. Quantification of the IgG2/4 kappa Monoclonal Therapeutic Eculizumab from Serum Using Isotype Specific Affinity Purification and Microflow LC-ESI-Q-TOF Mass Spectrometry

    NASA Astrophysics Data System (ADS)

    Ladwig, Paula M.; Barnidge, David R.; Willrich, Maria A. V.

    2017-05-01

    As therapeutic monoclonal antibodies (mAbs) become more humanized, traditional tryptic peptide approaches used to measure biologics in serum become more challenging since unique clonotypic peptides used for quantifying the mAb may also be found in the normal serum polyclonal background. An alternative approach is to monitor the unique molecular mass of the intact light chain portion of the mAbs using liquid chromatography-mass spectrometry (LC-MS). Distinguishing a therapeutic mAb from a patient's normal polyclonal immunoglobulin (Ig) repertoire is the primary limiting factor when determining the limit of quantitation (LOQ) in serum. The ability to selectively extract subclass specific Igs from serum reduces the polyclonal background in a sample. We present here the development of an LC-MS method to quantify eculizumab in serum. Eculizumab is a complement component 5 (C5) binding mAb that is fully humanized and contains portions of both IgG2 and IgG4 subclasses. Our group developed a method that uses Life Technologies CaptureSelect IgG4 (Hu) affinity matrix. We show here the ability to quantitate eculizumab with a LOQ of 5 mcg/mL by removing the higher abundance IgG1, IgG2, and IgG3 from the polyclonal background, making this approach a simple and efficient procedure.

  14. Quantification of the IgG2/4 kappa Monoclonal Therapeutic Eculizumab from Serum Using Isotype Specific Affinity Purification and Microflow LC-ESI-Q-TOF Mass Spectrometry

    NASA Astrophysics Data System (ADS)

    Ladwig, Paula M.; Barnidge, David R.; Willrich, Maria A. V.

    2016-12-01

    As therapeutic monoclonal antibodies (mAbs) become more humanized, traditional tryptic peptide approaches used to measure biologics in serum become more challenging since unique clonotypic peptides used for quantifying the mAb may also be found in the normal serum polyclonal background. An alternative approach is to monitor the unique molecular mass of the intact light chain portion of the mAbs using liquid chromatography-mass spectrometry (LC-MS). Distinguishing a therapeutic mAb from a patient's normal polyclonal immunoglobulin (Ig) repertoire is the primary limiting factor when determining the limit of quantitation (LOQ) in serum. The ability to selectively extract subclass specific Igs from serum reduces the polyclonal background in a sample. We present here the development of an LC-MS method to quantify eculizumab in serum. Eculizumab is a complement component 5 (C5) binding mAb that is fully humanized and contains portions of both IgG2 and IgG4 subclasses. Our group developed a method that uses Life Technologies CaptureSelect IgG4 (Hu) affinity matrix. We show here the ability to quantitate eculizumab with a LOQ of 5 mcg/mL by removing the higher abundance IgG1, IgG2, and IgG3 from the polyclonal background, making this approach a simple and efficient procedure.

  15. Quantification of the IgG2/4 kappa Monoclonal Therapeutic Eculizumab from Serum Using Isotype Specific Affinity Purification and Microflow LC-ESI-Q-TOF Mass Spectrometry.

    PubMed

    Ladwig, Paula M; Barnidge, David R; Willrich, Maria A V

    2017-05-01

    As therapeutic monoclonal antibodies (mAbs) become more humanized, traditional tryptic peptide approaches used to measure biologics in serum become more challenging since unique clonotypic peptides used for quantifying the mAb may also be found in the normal serum polyclonal background. An alternative approach is to monitor the unique molecular mass of the intact light chain portion of the mAbs using liquid chromatography-mass spectrometry (LC-MS). Distinguishing a therapeutic mAb from a patient's normal polyclonal immunoglobulin (Ig) repertoire is the primary limiting factor when determining the limit of quantitation (LOQ) in serum. The ability to selectively extract subclass specific Igs from serum reduces the polyclonal background in a sample. We present here the development of an LC-MS method to quantify eculizumab in serum. Eculizumab is a complement component 5 (C5) binding mAb that is fully humanized and contains portions of both IgG2 and IgG4 subclasses. Our group developed a method that uses Life Technologies CaptureSelect IgG4 (Hu) affinity matrix. We show here the ability to quantitate eculizumab with a LOQ of 5 mcg/mL by removing the higher abundance IgG1, IgG2, and IgG3 from the polyclonal background, making this approach a simple and efficient procedure. Graphical Abstract ᅟ.

  16. Paroxysmal cold hemoglobinuria (PCH)

    MedlinePlus

    ... test is negative. Donath-Landsteiner test is positive. Lactate dehydrogenase level is high. Treatment Treating the underlying ... Updated by: Todd Gersten, MD, Hematology/Oncology, Florida Cancer Specialists & Research Institute, Wellington, FL. Review provided by ...

  17. Paroxysmal Nocturnal Hemoglobinuria (PNH)

    MedlinePlus

    ... system. When red blood cells break apart, the hemoglobin inside is released. Hemoglobin is the red part of red blood cells ... carries oxygen around the body. The release of hemoglobin causes many of the PNH symptoms. PNH can ...

  18. Paroxysmal nocturnal hemoglobinuria (PNH)

    MedlinePlus

    ... and intravascular hemolytic anemias. In: Goldman L, Schafer AI, eds. Goldman's Cecil Medicine . 25th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 160. Schafer AI. Thrombotic disorders. In: Goldman L, Schafer AI, eds. ...

  19. CALUTRON RECEIVER

    DOEpatents

    Barnes, S.W.

    1959-08-25

    An improvement in a calutron receiver for collecting the isotopes ts described. The electromagnetic separation of the isotopes produces a mass spectrum of closely adjacent beams of ions at the foci regions, and a dividing wall between the two pockets is arranged at an angle. Substantially all of the tons of the less abundant isotope enter one of the pockets and strike one side of the wall directly, while substantially none of the tons entering the other pocket strikes the wall directly.

  20. Red Kidney: Kidney Transplant From a Deceased Donor Who Received Massive Blood Transfusion During Cardiopulmonary Bypass.

    PubMed

    Bell, Richard; Hanif, Faisal; Prasad, Padmini; Ahmad, Niaz

    2016-06-01

    Here, we present a case of a deceased-donor kidney transplant. The brain-dead donor had received a massive blood transfusion during cardiopulmonary bypass, which lead to hemolysis, hemoglobinuria, acute kidney injury, and renal replacement therapy. The kidney appeared red after in situ flush. Postoperatively, the recipient developed delayed graft function. Protocol biopsy during the postoperative period revealed the widespread deposition of heme pigment in the renal tubules. Massive blood transfusion and cardiopulmonary bypass surgery are associated with hemolysis and heme pigment deposition in the renal tubules, which subsequently lead to acute kidney injury. Kidneys from such donors appear red and, while this does not preclude transplant, are likely to develop delayed graft function.

  1. Ex vivo expansion and long-term hematopoietic reconstitution ability of sorted CD34+CD59+ cells from patients with paroxysmal nocturnal hemoglobinuria.

    PubMed

    Xiao, Juan; Han, Bing; Wu, Yong-Ji; Zhong, Yu-ping; Sun, Wan-ling

    2010-07-01

    Autologous bone marrow transplantation (ABMT) for paroxysmal nocturnal hemoglobinuria (PNH) remains difficult so far. To expand residual normal CD34(+)CD59(+) cells isolated from patients with PNH and observe the long-term hematopoietic reconstruction ability of the expanded cells both ex vivo and in vivo, CD34(+)CD59(+) cells from 13 PNH patients and CD34(+) cells from 11 normal controls were separated from bone marrow mononuclear cells first by immunomagnetic microbeads and then by flow cytometry autoclone sorting. The cells were then cultivated under different conditions. The long-term hematopoietic supporting ability of expanded CD34(+)CD59(+) cells was evaluated by long-term culture in semi-solid medium in vitro and long-term engraftment in irradiated severe combined immunodeficiency (SCID) mice in vivo. The best combination of hematopoietic growth factors for ex vivo expansion was SCF + IL-3 + IL-6 + FL + Tpo + Epo. The most suitable time for harvest was on day 7. CD34(+)CD59(+) PNH cells retained strong colony-forming capacity even after expansion. The survival rate, complete blood cell count recovery on day 90, and human CD45 expression in different organs were similar between the irradiated SCID mice transplanted with expanded CD34(+)CD59(+) PNH cells and those with normal CD34(+) cells (P > 0.05) both in primary and secondary transplantation. These data provided a new potential way of managing PNH with ABMT.

  2. A SIN lentiviral vector containing PIGA cDNA allows long-term phenotypic correction of CD34+-derived cells from patients with paroxysmal nocturnal hemoglobinuria.

    PubMed

    Robert, David; Mahon, François-Xavier; Richard, Emmanuel; Etienne, Gabriel; de Verneuil, Hubert; Moreau-Gaudry, François

    2003-03-01

    Paroxysmal nocturnal hemoglobinuria (PNH) is a hematopoietic stem cell (HSC) disorder in which an acquired somatic mutation of the X-linked PIGA gene results in a deficiency in GPI-anchored surface proteins. Clinically, PNH is dominated by a chronic hemolytic anemia, often associated with recurrent nocturnal exacerbations, neutropenia, thrombocytopenia, and thrombotic tendency. Allogenic bone marrow transplantation is the only potentially curative treatment for severe forms of PNH but is associated with a high treatment-related morbidity and mortality. HSC gene therapy could provide a new therapeutic option, especially when an HLA-matched donor is not available. To develop an efficient gene transfer approach, we have designed a new SIN lentiviral vector (TEPW) that contains the PIGA cDNA driven by the human elongation factor 1 alpha promoter, the central DNA flap of HIV-1, and the WPRE cassette. TEPW transduction led to a complete surface expression of the GPI anchor and CD59 in PIGA-deficient cell lines without any selection procedure. Moreover, efficient gene transfer was achieved in bone marrow and mobilized peripheral blood CD34(+) cells derived from two patients with severe PNH disease. This expression was stable during erythroid, myeloid, and megakaryocytic liquid culture differentiation. CD59 surface cell expression was fully restored during 5 weeks of long-term culture.

  3. Radiation receiver

    DOEpatents

    Hunt, A.J.

    1983-09-13

    The apparatus for collecting radiant energy and converting same to alternate energy form includes a housing having an interior space and a radiation transparent window allowing, for example, solar radiation to be received in the interior space of the housing. Means are provided for passing a stream of fluid past said window and for injecting radiation absorbent particles in said fluid stream. The particles absorb the radiation and because of their very large surface area, quickly release the heat to the surrounding fluid stream. The fluid stream particle mixture is heated until the particles vaporize. The fluid stream is then allowed to expand in, for example, a gas turbine to produce mechanical energy. In an aspect of the present invention properly sized particles need not be vaporized prior to the entrance of the fluid stream into the turbine, as the particles will not damage the turbine blades. In yet another aspect of the invention, conventional fuel injectors are provided to inject fuel into the fluid stream to maintain the proper temperature and pressure of the fluid stream should the source of radiant energy be interrupted. In yet another aspect of the invention, an apparatus is provided which includes means for providing a hot fluid stream having hot particles disbursed therein which can radiate energy, means for providing a cooler fluid stream having cooler particles disbursed therein, which particles can absorb radiant energy and means for passing the hot fluid stream adjacent the cooler fluid stream to warm the cooler fluid and cooler particles by the radiation from the hot fluid and hot particles. 5 figs.

  4. Radiation receiver

    DOEpatents

    Hunt, Arlon J.

    1983-01-01

    The apparatus for collecting radiant energy and converting same to alternate energy form includes a housing having an interior space and a radiation transparent window allowing, for example, solar radiation to be received in the interior space of the housing. Means are provided for passing a stream of fluid past said window and for injecting radiation absorbent particles in said fluid stream. The particles absorb the radiation and because of their very large surface area, quickly release the heat to the surrounding fluid stream. The fluid stream particle mixture is heated until the particles vaporize. The fluid stream is then allowed to expand in, for example, a gas turbine to produce mechanical energy. In an aspect of the present invention properly sized particles need not be vaporized prior to the entrance of the fluid stream into the turbine, as the particles will not damage the turbine blades. In yet another aspect of the invention, conventional fuel injectors are provided to inject fuel into the fluid stream to maintain the proper temperature and pressure of the fluid stream should the source of radiant energy be interrupted. In yet another aspect of the invention, an apparatus is provided which includes means for providing a hot fluid stream having hot particles disbursed therein which can radiate energy, means for providing a cooler fluid stream having cooler particles disbursed therein, which particles can absorb radiant energy and means for passing the hot fluid stream adjacent the cooler fluid stream to warm the cooler fluid and cooler particles by the radiation from the hot fluid and hot particles.

  5. Standardized high-sensitivity flow cytometry testing for paroxysmal nocturnal hemoglobinuria in children with acquired bone marrow failure disorders: A single center US study.

    PubMed

    Donohue, Rachel E; Marcogliese, Andrea N; Sasa, Ghadir S; Elghetany, M Tarek; Redkar, Alka A; Bertuch, Alison A; Curry, Choladda V

    2017-06-02

    Paroxysmal nocturnal hemoglobinuria (PNH) is a rare, acquired hematopoietic stem cell disorder that has not been well-documented in children, particularly those with acquired bone marrow failure disorders (ABMFD)-acquired aplastic anemia (AAA) and myelodysplastic syndrome (MDS). Therefore, we sought to determine the prevalence of PNH populations in children with ABMFD. PNH testing was performed in children with an ABMFD diagnosis using high sensitivity (≥0.01%) fluorescent aerolysin (FLAER)-based assay according to 2010 International Clinical Cytometry Society (ICCS) PNH Consensus Guidelines and 2012 Practical PNH Guidelines. FLAER/CD64/CD15/CD24/CD14/CD45 and CD235a/CD59 panels were used for white blood cell and red blood cell testing, respectively. Thirty-seven patients with ABMFD (34 AAA, 3 MDS) were included (17M/20F, age 2-18 years, median 9 years). PNH populations were identified in 17 of 37 (46%) patients. Of the 17 patients with PNH populations identified, 7 were PNH clones (>1% PNH population), and 10 had minor PNH population or rare cells with PNH phenotype (≤1% PNH population). This is the first study to use a standardized high-sensitivity FLAER-based flow cytometry assay and the recommended cutoff of 0.01% to identify cells with PNH phenotype in pediatric patients with ABMFD in the United States. The identification of a PNH population in 46% of ABMFD supports the recommendation for high sensitivity PNH testing in children with these disorders. As a less sensitive assay using a cutoff of ≥ 1% PNH population would have missed 10 (27%) patients with minor PNH population or rare cells with PNH phenotype. © 2017 International Clinical Cytometry Society. © 2017 International Clinical Cytometry Society.

  6. Quantitation of CD55 and CD59 expression on reticulocytes and mature erythrocytes in paroxysmal nocturnal hemoglobinuria, aplastic anemia, and healthy control subjects.

    PubMed

    Kim, Yeongsic; Lim, Jihyang; Kim, Myungshin; Kim, Yonggoo; Lee, Jong-Wook; Han, Kyungja

    2010-01-01

    Since PNH occasionally results in bone marrow failure, it is difficult to differentiate PNH from AA with small numbers of CD(55) (-)CD(59) (-) erythrocytes. We quantified CD55 and CD59 molecules expressed on normal reticulocytes and mature erythrocytes of paroxysmal nocturnal hemoglobinuria (PNH), aplastic anemia (AA), and normal individuals in order to determine their usefulness for differentiation between PNH and AA. A total of 56 patients (AA 39 patients, PNH 17 patients) and 10 healthy volunteers were enrolled. Two-color flow cytometric analyses were conducted using thiazole orange, anti-CD55 and CD59 monoclonal antibodies to identify CD(55) (-)CD(59) (-) reticulocytes and mature erythrocytes. Mean fluorescence level of CD(55) (+) mature erythrocytes was lowest in the PNH patients (13.2 x 10(3) MESF), and was significantly lower than in normal controls (16.7 x 10(3) MESF, p <0.05), and highest in the AA subjects (22.8 x 10(3) MESF). Mean fluorescence level of CD(59) (+) mature erythrocytes was lowest in the PNH subjects (24.5 x 10(3) MESF), significantly less than in normal controls (39.0 x 10(3) MESF, p <0.05), and highest in the AA subjects (49.2 x 10(3) MESF). Total reticulocyte counts correlated strongly with the CD(55) (-)CD(59) (-) reticulocytes. Comparative quantitative analysis of CD55 and CD59 molecules expressed on normal erythrocytes may be useful in differentiating PNH from AA patients with small numbers of PNH-phenotype erythrocytes, and the total reticulocyte count may prove useful as a marker for PNH clone size.

  7. Normal patterns of expression of glycosylphosphatidylinositol-anchored proteins on different subsets of peripheral blood cells: a frame of reference for the diagnosis of paroxysmal nocturnal hemoglobinuria.

    PubMed

    Hernández-Campo, Pilar María; Almeida, Julia; Sánchez, María Luz; Malvezzi, Mariester; Orfao, Alberto

    2006-03-01

    Evaluation of the expression of glycosylphosphatidylinositol-anchored membrane proteins (GPI-AP) is currently used for the diagnosis of paroxysmal nocturnal hemoglobinuria (PNH). In this study, we analyzed the amount of expression of a wide variety of GPI-AP in different subsets of hematopoietic cells present in normal peripheral blood (PB), to establish their normal patterns of expression and provide a frame of reference for the definition of the best combination of GPI-AP and PB cell subsets to be applied in the diagnosis and monitoring of PNH. Our results show variable patterns of expression of different GPI-AP in distinct subsets of normal PB cells. Combined use of CD55 and CD59 represented the most useful dual-marker combination; however, its utility remained suboptimal for several subsets of leukocytes and for platelets. For some cell subsets such as the neutrophils additional useful markers could be selected from a relatively broad panel (CD16/CD24/CD55/CD59/CD66b/CD157), whereas for other cell subsets the number of useful antigens was either restricted (monocytes: CD14/CD55/CD157; B cells: CD24/CD48/CD52/CD55; CD4+ T cells: CD48/CD52/CD55; eosinophils: CD55/CD59; CD8+ T cells: CD48/CD55) or limited to a single marker (CD48 on CD56low NK cells, CD55 on BDCA3- dendritic cells and CD56high NK cells, and CD59 for red cells), from all antigens analyzed. Copyright 2005 International Society for Analytical Cytology.

  8. [Long-term ability for hematopoiesis of CD34(+)CD59(+) cells from patients with paroxysmal nocturnal hemoglobinuria: experiment with mice].

    PubMed

    Sun, Wan-Ling; Han, Bing; Wang, Xuan; Zhong, Yu-Ping; Zhuang, Jun-Ling; Shen, Ti; Wu, Yong-Ji

    2007-11-13

    To obtain the evidence of long-term hematopoiesis by normal clone stem cells from patients with paroxysmal nocturnal hemoglobinuria (PNH). 10 ml fresh bone marrow was collected from 2 PNH patients. Normal bone marrow was obtained from the ribs resected during operation of 2 patients without hematopathy. CD34(+)CD59(+) cells were isolated, purified, and expended. 12 total body irradiated SCID mice were divided into 2 equal group to undergo transplantation of the expanded CD34(+)CD59(+) cells from PNH patients (experiment group 1) or normal patients (control group 1). Four mice underwent transfusion of cell-free medium as blank control group 1. 30 and 60 days after the transplantation peripheral blood samples were collected and 90 days after the transplantation heart blood samples were collected. Spleens were taken out to prepare suspension of splenocytes and bacterium-free bone marrow cell suspension was prepared from the bilateral femurs. 90 days after the primary transplantation another 16 mice underwent total body irradiation and then divided into 2 equal groups to undergo transplantation of the bone marrow cells of the mice of the experiment group 1 and control group 1 (experiment group 2 and control group 2). Another 4 mice were transfused with cell-free medium fluid (blank control group 2). The levels of blood cells of all groups were calculated 30, 60, and 90 days after the primary and 30 days after the secondary transplantation. The cell percentages of peripheral blood, spleen, and bone marrow after the primary transplantation and 30 days after the secondary transplantation were detected by flow cytometry. PCR was used to detect whether the sex determining region Y existed in the female SCID mice after transplantation. Ninety days after primary transplantation, the peripheral blood cell levels of both experiment group 1 and control group 1 recovered to normal. Expression of CD45 was detected in the mice without significant difference between the 2 groups

  9. Putting the "receive" in accounts receivable.

    PubMed

    McDaniel, John W; Baum, Neil

    2006-01-01

    There isn't a practice in the United States that doesn't have a concern about accounts receivable. The financial success of any practice depends on the care and feeding of the accounts receivable. This is not an area of practice management that can be taken lightly or delegated to someone who is not attentive to detail and doggedly persistent. In this article, we will discuss how to identify problematic accounts receivable and what can be done to bring the accounts receivable under control. We will provide you with a plan of action that can be adopted by any practice regardless of size, number of physicians, or whether the practice uses in-house billing or outsources its billing arrangements.

  10. Spaceborne receivers: Basic principles

    NASA Technical Reports Server (NTRS)

    Stacey, J. M.

    1984-01-01

    The underlying principles of operation of microwave receivers for space observations of planetary surfaces were examined. The design philosophy of the receiver as it is applied to operate functionally as an efficient receiving system, the principle of operation of the key components of the receiver, and the important differences among receiver types are explained. The operating performance and the sensitivity expectations for both the modulated and total power receiver configurations are outlined. The expressions are derived from first principles and are developed through the important intermediate stages to form practicle and easily applied equations. The transfer of thermodynamic energy from point to point within the receiver is illustrated. The language of microwave receivers is applied statistics.

  11. Solar heat receiver

    DOEpatents

    Hunt, A.J.; Hansen, L.J.; Evans, D.B.

    1982-09-29

    A receiver is described for converting solar energy to heat a gas to temperatures from 700 to 900/sup 0/C. The receiver is formed to minimize impingement of radiation on the walls and to provide maximum heating at and near the entry of the gas exit. Also, the receiver is formed to provide controlled movement of the gas to be heated to minimize wall temperatures. The receiver is designed for use with gas containing fine heat absorbing particles, such as carbon particles.

  12. Solar heat receiver

    DOEpatents

    Hunt, Arlon J.; Hansen, Leif J.; Evans, David B.

    1985-01-01

    A receiver for converting solar energy to heat a gas to temperatures from 700.degree.-900.degree. C. The receiver is formed to minimize impingement of radiation on the walls and to provide maximum heating at and near the entry of the gas exit. Also, the receiver is formed to provide controlled movement of the gas to be heated to minimize wall temperatures. The receiver is designed for use with gas containing fine heat absorbing particles, such as carbon particles.

  13. Data-fusion receiver

    SciTech Connect

    Gabelmann, Jeffrey M.; Kattner, J. Stephen; Houston, Robert A.

    2006-12-19

    This invention is an ultra-low frequency electromagnetic telemetry receiver which fuses multiple input receive sources to synthesize a decodable message packet from a noise corrupted telemetry message string. Each block of telemetry data to be sent to the surface receiver from a borehole tool is digitally encoded into a data packet prior to transmission. The data packet is modulated onto the ULF EM carrier wave and transmitted from the borehole to the surface and then are simultaneously detected by multiple receive sensors disbursed within the rig environment. The receive sensors include, but are not limited to, electric field and magnetic field sensors. The spacing of the surface receive elements is such that noise generators are unequally coupled to each receive element due to proximity and/or noise generator type (i.e. electric or magnetic field generators). The receiver utilizes a suite of decision metrics to reconstruct the original, non noise-corrupted data packet from the observation matrix via the estimation of individual data frames. The receiver will continue this estimation process until: 1) the message validates, or 2) a preset "confidence threshold" is reached whereby frames within the observation matrix are no longer "trusted".

  14. Hybrid receiver study

    NASA Technical Reports Server (NTRS)

    Stone, M. S.; Mcadam, P. L.; Saunders, O. W.

    1977-01-01

    The results are presented of a 4 month study to design a hybrid analog/digital receiver for outer planet mission probe communication links. The scope of this study includes functional design of the receiver; comparisons between analog and digital processing; hardware tradeoffs for key components including frequency generators, A/D converters, and digital processors; development and simulation of the processing algorithms for acquisition, tracking, and demodulation; and detailed design of the receiver in order to determine its size, weight, power, reliability, and radiation hardness. In addition, an evaluation was made of the receiver's capabilities to perform accurate measurement of signal strength and frequency for radio science missions.

  15. Right to Receive.

    ERIC Educational Resources Information Center

    Oborn, Richard

    The concept of a United States citizen's right to receive information is acquiring increased judicial recognition. This report traces the evolution of that right from its philosophical basis in the United States Consitution, through its interpretation by the Supreme Court, up to the current concern that the public receive certain economic…

  16. Flight termination receiver catalog

    NASA Astrophysics Data System (ADS)

    1993-02-01

    This catalog provides reference information on ultra-high frequency flight termination receivers used at various U.S. missile ranges and test facilities. It is not intended to be a comprehensive review of all available flight termination receivers. Inclusion in this catalog does not constitute approval or endorsement for use at any government installation. Information in this catalog was extracted from manufacturers' specifications.

  17. Flight termination receiver catalog

    NASA Astrophysics Data System (ADS)

    1984-07-01

    This catalog provides reference information on ultrahigh-frequency flight termination receivers used at various U.S. missile ranges and test facilities. It is not intended to be a comprehensive review of all available flight termination receivers, and inclusion of hardware in this catalog does not constitute approval or endorsement for use at any government installation. Use of a specific receiver at a missile range or test facility requires the approval of the Commander of that installation. Approval for use of a particular receiver on a given missile at one installation does not constitute automatic approval for use of the same receiver on other missiles at the same installation or on the same missile at other installations. The information in this catalog has been extracted from manufacturers' specifications. It is provided as reference material only and is not intended as an endorsement of any model.

  18. CALUTRON RECEIVER STRUCTURE

    DOEpatents

    Roush, J.L.

    1959-09-01

    A receiver is described for collecting isotopes in a calutron The receiver has several compartments, formed by a sertes of parallel metal plates and an open front. Each plate has flanges which space it from the other plates and a flexible extension pressing against a common supporting red to maintain the plate in assembled relation when all but the last rod is removed. The plates may be removed individualy from the front of the receiver, cleaned ard replaced without disturbing the alignment of the other plates.

  19. 30-micron heterodyne receiver

    NASA Technical Reports Server (NTRS)

    Kostiuk, Theodor; Spears, David L.

    1987-01-01

    Advantages and constraints of remote measurements using heterodyne spectroscopy near 30 microns are discussed. The state of the art of wideband HgCdTe photomixers and PbSnSe diode-laser local oscillators being developed for FIR heterodyne receivers is described. The first compact 30-micron heterodyne radiometer was built, and initial results at 28-microns show about 2-percent mixer efficiency for a 500-MHz-bandwidth receiver. Factors limiting receiver performance are discussed, along with the projected sensitivity of new interdigitated-electrode HgCdTe photoconductor mixers being developed for operation up to 200 microns.

  20. Ultrasonic pulser-receiver

    DOEpatents

    Taylor, Steven C.

    2006-09-12

    Ultrasonic pulser-receiver circuitry, for use with an ultrasonic transducer, the circuitry comprising a circuit board; ultrasonic pulser circuitry supported by the circuit board and configured to be coupled to an ultrasonic transducer and to cause the ultrasonic transducer to emit an ultrasonic output pulse; receiver circuitry supported by the circuit board, coupled to the pulser circuitry, including protection circuitry configured to protect against the ultrasonic pulse and including amplifier circuitry configured to amplify an echo, received back by the transducer, of the output pulse; and a connector configured to couple the ultrasonic transducer directly to the circuit board, to the pulser circuitry and receiver circuitry, wherein impedance mismatches that would result if the transducer was coupled to the circuit board via a cable can be avoided.

  1. Cryogenic microwave channelized receiver

    SciTech Connect

    Rauscher, C.; Pond, J.M.; Tait, G.B.

    1996-07-01

    The channelized receiver being presented demonstrates the use of high temperature superconductor technology in a microwave system setting where superconductor, microwave-monolithic-integrated-circuit, and hybrid-integrated-circuit components are united in one package and cooled to liquid-nitrogen temperatures. The receiver consists of a superconducting X-band four-channel demultiplexer with 100-MHz-wide channels, four commercial monolithically integrated mixers, and four custom-designed hybrid-circuit detectors containing heterostructure ramp diodes. The composite receiver unit has been integrated into the payload of the second-phase NRL high temperature superconductor space experiment (HTSSE-II). Prior to payload assembly, the response characteristics of the receiver were measured as functions of frequency, temperature, and drive levels. The article describes the circuitry, discusses the key issues related to design and implementation, and summarizes the experimental results.

  2. Ceramic Solar Receiver

    NASA Technical Reports Server (NTRS)

    Robertson, C., Jr.

    1984-01-01

    Solar receiver uses ceramic honeycomb matrix to absorb heat from Sun and transfer it to working fluid at temperatures of 1,095 degrees and 1,650 degrees C. Drives gas turbine engine or provides heat for industrial processes.

  3. Solar energy receiver

    DOEpatents

    Schwartz, Jacob

    1978-01-01

    An improved long-life design for solar energy receivers provides for greatly reduced thermally induced stress and permits the utilization of less expensive heat exchanger materials while maintaining receiver efficiencies in excess of 85% without undue expenditure of energy to circulate the working fluid. In one embodiment, the flow index for the receiver is first set as close as practical to a value such that the Graetz number yields the optimal heat transfer coefficient per unit of pumping energy, in this case, 6. The convective index for the receiver is then set as closely as practical to two times the flow index so as to obtain optimal efficiency per unit mass of material.

  4. Receiver Gain Modulation Circuit

    NASA Technical Reports Server (NTRS)

    Jones, Hollis; Racette, Paul; Walker, David; Gu, Dazhen

    2011-01-01

    A receiver gain modulation circuit (RGMC) was developed that modulates the power gain of the output of a radiometer receiver with a test signal. As the radiometer receiver switches between calibration noise references, the test signal is mixed with the calibrated noise and thus produces an ensemble set of measurements from which ensemble statistical analysis can be used to extract statistical information about the test signal. The RGMC is an enabling technology of the ensemble detector. As a key component for achieving ensemble detection and analysis, the RGMC has broad aeronautical and space applications. The RGMC can be used to test and develop new calibration algorithms, for example, to detect gain anomalies, and/or correct for slow drifts that affect climate-quality measurements over an accelerated time scale. A generalized approach to analyzing radiometer system designs yields a mathematical treatment of noise reference measurements in calibration algorithms. By treating the measurements from the different noise references as ensemble samples of the receiver state, i.e. receiver gain, a quantitative description of the non-stationary properties of the underlying receiver fluctuations can be derived. Excellent agreement has been obtained between model calculations and radiometric measurements. The mathematical formulation is equivalent to modulating the gain of a stable receiver with an externally generated signal and is the basis for ensemble detection and analysis (EDA). The concept of generating ensemble data sets using an ensemble detector is similar to the ensemble data sets generated as part of ensemble empirical mode decomposition (EEMD) with exception of a key distinguishing factor. EEMD adds noise to the signal under study whereas EDA mixes the signal with calibrated noise. It is mixing with calibrated noise that permits the measurement of temporal-functional variability of uncertainty in the underlying process. The RGMC permits the evaluation of EDA by

  5. Advanced Solar Receivers

    NASA Technical Reports Server (NTRS)

    Owen, W. A.

    1984-01-01

    Low thermal efficiencies in solar receivers are discussed in terms of system design. It is recommended that careful attention be given to the overall thermal systems design, especially to conductive losses about the window and areas of relatively thin insulation. If the cavity design is carefully managed to insure a small, minimally reradiating aperture, the goal of a very high efficiency cavity receiver is a realistic one.

  6. OCD RADIO ALERT RECEIVERS.

    DTIC Science & Technology

    for methods of operating a radioalert system were established in conjunction with OCD representatives. Four types of operation were selected. Three...models each of these four receiver types were fabricated and tested. The total of 12 laboratory models were delivered to OCD . Test equipment...suitable for demonstrating the two most promising receiver types was also assembled, and delivered to OCD . A preliminary analysis of the cost of mass

  7. Project Echo: Receiving System

    NASA Technical Reports Server (NTRS)

    Ohm, E. A.

    1961-01-01

    A tracking horn-reflector antenna, a maser preamplifier (and standby parametric preamplifier), and a special FM demodulator were combined to form a low-noise receiving system which made possible the establishment of a high-quality voice circuit via the Echo I passive satellite. This paper describes the 2390-Mc receiving system located at the Bell Telephone Laboratories facility in Holmdel, New Jersey.

  8. Development of a disease-specific quality of life questionnaire for patients with aplastic anemia and/or paroxysmal nocturnal hemoglobinuria (QLQ-AA/PNH)-report on phases I and II.

    PubMed

    Groth, Martha; Singer, Susanne; Niedeggen, Cathrin; Petermann-Meyer, Andrea; Röth, Alexander; Schrezenmeier, Hubert; Höchsmann, Britta; Brümmendorf, Tim H; Panse, Jens

    2017-02-01

    Acquired aplastic anemia (AA) and paroxysmal nocturnal hemoglobinuria (PNH) are interrelated ultra-rare diseases. Quality of life (QoL) evaluation tools used in studies for AA and PNH are unspecific and designed for cancer patients (e.g., the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire, EORTC QLQ-C30). Given the complexity of AA and PNH, variation in symptoms and treatments, younger age of many patients, and the fact that AA and PNH are not classified as malignant diseases, it is likely that cancer-specific questionnaires are inappropriate. We generate an AA/PNH-specific QoL questionnaire (QLQ-AA/PNH), performed according to EORTC guidelines. QoL issues were obtained from the literature and interviews with patients and physicians (phase I), then ranked by patients and physicians. In phase II, items were created. Patients in more than 25 German and Swiss cities were interviewed face to face. In phase I, interviews of 19 patients and 8 physicians specialized in AA/PNH treatment resulted in 649 QoL issues; these were condensed to 175 and graded according to their importance by 30 patients and 14 physicians (phase II). Five physicians took part in phases I and II. Altogether, 97 issues were rated important. Twelve EORTC QLQ-C30 items were not rated important, while several new QoL aspects were brought up. Modifications in wording and phrasing led to two questionnaires with 77 items regarding general QoL aspects and 20 items regarding medical care. Important QoL aspects of PNH/AA patients are inappropriately captured with available QoL tools. Developing a new QoL questionnaire specific for this patient group is warranted.

  9. Highly directional acoustic receivers

    NASA Astrophysics Data System (ADS)

    Cray, Benjamin A.; Evora, Victor M.; Nuttall, Albert H.

    2003-03-01

    The theoretical directivity of a single combined acoustic receiver, a device that can measure many quantities of an acoustic field at a collocated point, is presented here. The formulation is developed using a Taylor series expansion of acoustic pressure about the origin of a Cartesian coordinate system. For example, the quantities measured by a second-order combined receiver, denoted a dyadic sensor, are acoustic pressure, the three orthogonal components of acoustic particle velocity, and the nine spatial gradients of the velocity vector. The power series expansion, which can be of any order, is cast into an expression that defines the directivity of a single receiving element. It is shown that a single highly directional dyadic sensor can have a directivity index of up to 9.5 dB. However, there is a price to pay with highly directive sensors; these sensors can be significantly more sensitive to nonacoustic noise sources.

  10. Central solar energy receiver

    DOEpatents

    Drost, M. Kevin

    1983-01-01

    An improved tower-mounted central solar energy receiver for heating air drawn through the receiver by an induced draft fan. A number of vertically oriented, energy absorbing, fin-shaped slats are radially arranged in a number of concentric cylindrical arrays on top of the tower coaxially surrounding a pipe having air holes through which the fan draws air which is heated by the slats which receive the solar radiation from a heliostat field. A number of vertically oriented and wedge-shaped columns are radially arranged in a number of concentric cylindrical clusters surrounding the slat arrays. The columns have two mirror-reflecting sides to reflect radiation into the slat arrays and one energy absorbing side to reduce reradiation and reflection from the slat arrays.

  11. Hanson receives Macelwane Medal

    NASA Astrophysics Data System (ADS)

    Ravishankara, A. R.; Hanson, David R.

    At the 1996 Spring Meeting in Baltimore, Maryland, David R. Hanson received the 1996 James B. Macelwane Medal, which recognizes significant contributions to the geophysical sciences by a young scientist of outstanding ability. The medal citation and Hanson's response are given here.

  12. Zero-power receiver

    SciTech Connect

    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.

  13. Submillimeter wave heterodyne receiver

    NASA Technical Reports Server (NTRS)

    Chattopadhyay, Goutam (Inventor); Manohara, Harish (Inventor); Siegel, Peter H. (Inventor); Ward, John (Inventor)

    2011-01-01

    In an embodiment, a submillimeter wave heterodyne receiver includes a finline ortho-mode transducer comprising thin tapered metallic fins deposited on a thin dielectric substrate to separate a vertically polarized electromagnetic mode from a horizontally polarized electromagnetic mode. Other embodiments are described and claimed.

  14. Received Pronunciation and "Realphonetik."

    ERIC Educational Resources Information Center

    Shibles, Warren

    1995-01-01

    This article argues that British Received Pronunciation (RP) is inconsistently defined, arbitrary, and anachronistic, and that it should be replaced as an instructional concept by British Pronunciation (BP), which would be based on an actual and adequate descriptive phonetics, called here "Realphonetik." Contains 77 references. (MDM)

  15. Help Seeking and Receiving.

    ERIC Educational Resources Information Center

    Nadler, Arie

    Although social psychology has always had an interest in helping behavior, only recently has the full complexity of helping relations begun to be researched. Help seeking and receiving in the educational setting raise many issues regarding the use and effectiveness of the help itself. Central to all helping relations is the seeking/receiving…

  16. Olympus beacon receiver

    NASA Technical Reports Server (NTRS)

    Ostergaard, Jens

    1988-01-01

    A medium-size Beacon Receiving System for reception and processing of the B1 (20 GHz) and B2 (30 GHz) beacons from Olympus has been developed. Integration of B1 and B2 receiving equipment into one system using one antenna and a common computer for control and data processing provides the advantages of a compact configuration and synchronization of the two receiver chains. Range for co-polar signal attenuation meaurement is about 30 dB for both beacons, increasing to 40 dB for B2 if the receivers are synchronized to B1. The accuracy is better than 0.5 dB. Cross-polarization discriminations of the order of 10 to 30 dB may be determined with an accuracy of 1 to 2 dB. A number of radiometers for complementary measurements of atmospheric attenuation of 13 to 30 GHz has also been constructed. A small multi-frequency system for operation around 22 GHz and 31 GHz is presently under development.

  17. Simplified OMEGA receivers

    NASA Technical Reports Server (NTRS)

    Burhans, R. W.

    1974-01-01

    The details are presented of methods for providing OMEGA navigational information including the receiver problem at the antenna and informational display and housekeeping systems based on some 4 bit data processing concepts. Topics discussed include the problem of limiters, zero crossing detectors, signal envelopes, internal timing circuits, phase counters, lane position displays, signal integrators, and software mapping problems.

  18. A digital beacon receiver

    NASA Technical Reports Server (NTRS)

    Ransome, Peter D.

    1988-01-01

    A digital satellite beacon receiver is described which provides measurement information down to a carrier/noise density ratio approximately 15 dB below that required by a conventional (phase locked loop) design. When the beacon signal fades, accuracy degrades gracefully, and is restored immediately (without hysteresis) on signal recovery, even if the signal has faded into the noise. Benefits of the digital processing approach used include the minimization of operator adjustments, stability of the phase measuring circuits with time, repeatability between units, and compatibility with equipment not specifically designed for propagation measuring. The receiver has been developed for the European Olympus satellite which has continuous wave (CW) beacons at 12.5 and 29.7 GHz, and a switched polarization beacon at 19.8 GHz approximately, but the system can be reconfigured for CW and polarization-switched beacons at other frequencies.

  19. Multichannel homodyne receiver

    DOEpatents

    Landt, J.A.

    1981-01-19

    A homodyne radar transmitter/receiver device which produces a single combined output which contains modulated backscatter information for all phase conditions of both modulated and unmodulated backscatter signals is described. The device utilizes taps along coaxial transmission lines, strip transmission line, and waveguides which are spaced by 1/8 wavelength or 1/6 wavelength, etc. This greatly reduces costs by eliminating separate transmission and reception antennas and an expensive arrangement of power splitters and mixers utilized in the prior art.

  20. Multichannel homodyne receiver

    DOEpatents

    Landt, Jeremy A.

    1982-01-01

    A homodyne radar transmitter/receiver device which produces a single combined output which contains modulated backscatter information for all phase conditions of both modulated and unmodulated backscatter signals. The device utilizes taps along coaxial transmission lines, strip transmission line, and waveguides which are spaced by 1/8 wavelength or 1/6 wavelength, etc. This greatly reduces costs by eliminating separate transmission and reception antennas and an expensive arrangement of power splitters and mixers utilized in the prior art.

  1. The Themis solar receiver

    NASA Astrophysics Data System (ADS)

    Gravrand, J. M.; Pouget-Abadie, X.

    The theoretical modeling, materials, and design of the central receiver heat exchanger on the tower of the Themis solar power plant are presented. The receiver was conceived based on the incident solar flux at different times of the day and year and the efficiency of transferring the heat to molten salts. The square aperture admits energy at a peak rate of 3.402 MWth at some points, with heat transfer to the power loop resulting in a maximum efficiency of 25 percent. Optimization studies indicated a receiver inclined 30 deg from the horizontal to face the heliostat field, and the flux incident on the walls was mapped. Tubes filled with the salts at 250 C form the walls behind radiator fins and elevate the salt to temperatures up to a limit of 490 C. Measures taken to allow for the expansion of the cavity walls and to mount the heat exchange tubes for easy replacement are described, along with the instrumentation to measure performance, flux, and detect malfunctions due to perturbations in the fluid flow or failure of any of the components.

  2. LANL receiver system development

    SciTech Connect

    Laubscher, B.; Cooke, B.; Cafferty, M.; Olivas, N.

    1997-08-01

    The CALIOPE receiver system development at LANL is the story of two technologies. The first of these technologies consists of off-the-shelf mercury-cadmium-telluride (MCT) detectors and amplifiers. The vendor for this system is Kolmar Technologies. This system was fielded in the Tan Trailer I (TTI) in 1995 and will be referred to in this paper as GEN I. The second system consists of a MCT detector procured from Santa Barbara Research Center (SBRC) and an amplifier designed and built by LANL. This system was fielded in the Tan Trailer II (TTII) system at the NTS tests in 1996 and will be referred to as GEN II. The LANL CALIOPE experimental plan for 1996 was to improve the lidar system by progressing to a higher rep rate laser to perform many shots in a much shorter period of time. In keeping with this plan, the receiver team set a goal of developing a detector system that was background limited for the projected 100 nanosecond (ns) laser pulse. A set of detailed simulations of the DIAL lidar experiment was performed. From these runs, parameters such as optimal detector size, field of view of the receiver system, nominal laser return power, etc. were extracted. With this information, detector physics and amplifier electronic models were developed to obtain the required specifications for each of these components. These derived specs indicated that a substantial improvement over commercially available, off-the-shelf, amplifier and detector technologies would be needed to obtain the goals. To determine if the original GEN I detector was usable, the authors performed tests on a 100 micron square detector at cryogenic temperatures. The results of this test and others convinced them that an advanced detector was required. Eventually, a suitable detector was identified and a number of these single element detectors were procured from SBRC. These single element detectors were witness for the detector arrays built for another DOE project.

  3. Custom accounts receivable modeling.

    PubMed

    Veazie, J

    1994-04-01

    In hospital and clinic management, accounts are valued as units and handled equally--a $20 account receives the same minimum number of statements as a $20,000 account. Quite often, the sheer number of accounts a hospital or clinic has to handle forces executives to manage accounts by default and failure--accounts mature on an aging track and, if left unpaid by patients, eventually are sent to collections personnel. Of the bad-debt accounts placed with collections agencies, many are misclassified as charity or hardship cases, while others could be collected by hospital or clinic staff with a limited amount of additional effort.

  4. Ultra-wideband receiver

    DOEpatents

    McEwan, Thomas E.

    1996-01-01

    An ultra-wideband (UWB) receiver utilizes a strobed input line with a sampler connected to an amplifier. In a differential configuration, .+-.UWB inputs are connected to separate antennas or to two halves of a dipole antenna. The two input lines include samplers which are commonly strobed by a gating pulse with a very low duty cycle. In a single ended configuration, only a single strobed input line and sampler is utilized. The samplers integrate, or average, up to 10,000 pulses to achieve high sensitivity and good rejection of uncorrelated signals.

  5. Ultra-wideband receiver

    DOEpatents

    McEwan, Thomas E.

    1994-01-01

    An ultra-wideband (UWB) receiver utilizes a strobed input line with a sampler connected to an amplifier. In a differential configuration, .+-.UWB inputs are connected to separate antennas or to two halves of a dipole antenna. The two input lines include samplers which are commonly strobed by a gating pulse with a very low duty cycle. In a single ended configuration, only a single strobed input line and sampler is utilized. The samplers integrate, or average, up to 10,000 pulses to achieve high sensitivity and good rejection of uncorrelated signals.

  6. Ultra-wideband receiver

    DOEpatents

    McEwan, T.E.

    1996-06-04

    An ultra-wideband (UWB) receiver utilizes a strobed input line with a sampler connected to an amplifier. In a differential configuration, {+-}UWB inputs are connected to separate antennas or to two halves of a dipole antenna. The two input lines include samplers which are commonly strobed by a gating pulse with a very low duty cycle. In a single ended configuration, only a single strobed input line and sampler is utilized. The samplers integrate, or average, up to 10,000 pulses to achieve high sensitivity and good rejection of uncorrelated signals. 21 figs.

  7. Ultra-wideband receiver

    DOEpatents

    McEwan, T.E.

    1994-09-06

    An ultra-wideband (UWB) receiver utilizes a strobed input line with a sampler connected to an amplifier. In a differential configuration, [+-] UWB inputs are connected to separate antennas or to two halves of a dipole antenna. The two input lines include samplers which are commonly strobed by a gating pulse with a very low duty cycle. In a single ended configuration, only a single strobed input line and sampler is utilized. The samplers integrate, or average, up to 10,000 pulses to achieve high sensitivity and good rejection of uncorrelated signals. 16 figs.

  8. Weather Data Receiver

    NASA Technical Reports Server (NTRS)

    1982-01-01

    Northern Video Graphics, Inc. developed a low-cost satellite receiving system for users such as independent meteorologists, agribusiness firms, small airports or flying clubs, marine vessels and small TV stations. Called Video Fax, it is designed for use with certain satellites; the GOES (Geostationary Operational Environmental Satellite) spacecraft operated by the National Oceanic and Atmospheric Administration, the European Space Agency's Meteosat and Japan's Geostationary Meteorological Satellite. By dictum of the World Meteorological Organization, signals from satellites are available to anyone without cost so the Video Fax user can acquire signals directly from the satellite and cut out the middle man, enabling savings. Unit sells for about one-fifth the cost of the equipment used by TV stations. It consists of a two-meter antenna; a receiver; a microprocessor-controlled display computer; and a video monitor. Computer stores data from the satellites and converts it to an image which is displayed on the monitor. Weather map can be preserved as signal data on tape, or it can be stored in a video cassette as a permanent image.

  9. Digital Receiver Phase Meter

    NASA Technical Reports Server (NTRS)

    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 <5 microcycle/(Hz)1/2 and to be capable of determining the power spectral density of the phase difference over the frequency range from 1 mHz to 1 Hz. Such a phase meter could also be used on Earth to perform similar measurements in laser metrology of moving bodies. To illustrate part of the principle of operation of the phase meter, the figure includes a simplified block diagram of a basic singlechannel 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.

  10. Solar thermal energy receiver

    NASA Technical Reports Server (NTRS)

    Baker, Karl W. (Inventor); Dustin, Miles O. (Inventor)

    1992-01-01

    A plurality of heat pipes in a shell receive concentrated solar energy and transfer the energy to a heat activated system. To provide for even distribution of the energy despite uneven impingement of solar energy on the heat pipes, absence of solar energy at times, or failure of one or more of the heat pipes, energy storage means are disposed on the heat pipes which extend through a heat pipe thermal coupling means into the heat activated device. To enhance energy transfer to the heat activated device, the heat pipe coupling cavity means may be provided with extensions into the device. For use with a Stirling engine having passages for working gas, heat transfer members may be positioned to contact the gas and the heat pipes. The shell may be divided into sections by transverse walls. To prevent cavity working fluid from collecting in the extensions, a porous body is positioned in the cavity.

  11. ADMX Receiver and Analysis

    NASA Astrophysics Data System (ADS)

    Malagon, Ana; ADMX Collaboration

    2016-03-01

    ADMX looks for the excess radiation deposited into a cavity from the conversion of a dark matter axion into a microwave photon. The sensitivity of the experiment increases by reducing the background thermal noise and minimizing the electronic noise of the readout system. The axion masses that the experiment can detect are determined by the resonant frequency of the cavity mode of interest, which is tuned using a two rod configuration. One can also increase the search rate by measuring the output from two cavity modes at once, which requires two separate readout schemes. I will discuss the ADMX dual-channel receiver which has been upgraded to have near quantum-limited sensitivity on both channels, and describe how the correct modes are verified, using simulations, in the presence of dense electromagnetic structure. I conclude by describing upgrades to the ADMX analysis which allow for real-time exclusion limits. Supported by DOE Grants DE-FG02-97ER41029, DE-FG02-96ER40956, DE- AC52-07NA27344, DE-AC03-76SF00098, and the Livermore LDRD program.

  12. The calibration of Doppler receivers

    NASA Astrophysics Data System (ADS)

    Jaks, W.

    A study to determine the relative positions of the antennas of two simultaneously operating Doppler receivers and the systematic corrections needed for a given type of receiver is presented. The types of receivers included in the study are listed and results showing the differences between the geocentric coordinates of the antenna phase centers of the receivers are given. It is found that, for DOG receivers, each antenna phase center must be determined separately.

  13. Considerations for Future IGS Receivers

    NASA Astrophysics Data System (ADS)

    Humphreys, T. E.; Young, L. E.; Pany, T.

    2008-12-01

    Future International GNSS Service (IGS) receivers are considered against the backdrop of GNSS signal modernization and the IGS's goal of further improving the accuracy of its products. The purpose of this paper is to provide the IGS ---and any other group that uses geodetic-quality GNSS receivers---with a guide to making decisions about GNSS receivers. Modernized GNSS signals are analyzed with a view toward IGS applications. A schedule for minimum IGS receiver requirements is proposed. Features of idealized conceptual receivers are discussed. The prospects for standard commercial receivers and for software-defined GNSS receivers are examined. Recommendations are given for how the IGS should proceed in order to maximally benefit from the transformation in GNSS that will occur over the next decade. There are two reasons why it makes sense for the IGS to study GNSS receivers that will be integrated into its network in the coming years. First, the new GNSS signals that will come on line over the next decade will render current IGS receivers obsolete, so it is prudent to examine receiver options going forward. Second, the push to improve the accuracy of IGS products beyond current limits demands greater accuracy in the models used to describe receiver measurements. As a result, the IGS must demand from vendors more transparency into receiver firmware or adoption of user-specified algorithms. This paper considers future IGS receivers from four different points of view. Section 2 looks at modernized GNSS signals and their benefits for the IGS. Section 3 surveys the range of expected receiver capability. Section 4 considers current and future commercial geodetic-quality receivers. Section 5 considers software GNSS receivers as an alternative to less reconfigurable traditional receivers. Section 6 lays out the authors' recommendations to the IGS.

  14. Genetics Home Reference: paroxysmal nocturnal hemoglobinuria

    MedlinePlus

    ... that leads to the premature death and impaired production of blood cells. The disorder affects red blood cells (erythrocytes), which carry oxygen; white blood cells (leukocytes), which protect the body ...

  15. Real-time software receiver

    NASA Technical Reports Server (NTRS)

    Ledvina, Brent M. (Inventor); Psiaki, Mark L. (Inventor); Powell, Steven P. (Inventor); Kintner, Jr., Paul M. (Inventor)

    2006-01-01

    A real-time software receiver that executes on a general purpose processor. The software receiver includes data acquisition and correlator modules that perform, in place of hardware correlation, baseband mixing and PRN code correlation using bit-wise parallelism.

  16. Real-time software receiver

    NASA Technical Reports Server (NTRS)

    Ledvina, Brent M. (Inventor); Psiaki, Mark L. (Inventor); Powell, Steven P. (Inventor); Kintner, Jr., Paul M. (Inventor)

    2007-01-01

    A real-time software receiver that executes on a general purpose processor. The software receiver includes data acquisition and correlator modules that perform, in place of hardware correlation, baseband mixing and PRN code correlation using bit-wise parallelism.

  17. High-temperature ceramic receivers

    SciTech Connect

    Jarvinen, P. O.

    1980-01-01

    An advanced ceramic dome cavity receiver is discussed which heats pressurized gas to temperatures above 1800/sup 0/F (1000/sup 0/C) for use in solar Brayton power systems of the dispersed receiver/dish or central receiver type. Optical, heat transfer, structural, and ceramic material design aspects of the receiver are reported and the development and experimental demonstration of a high-temperature seal between the pressurized gas and the high-temperature silicon carbide dome material is described.

  18. High temperature solar thermal receiver

    NASA Technical Reports Server (NTRS)

    1979-01-01

    A design concept for a high temperature solar thermal receiver to operate at 3 atmospheres pressure and 2500 F outlet was developed. The performance and complexity of windowed matrix, tube-header, and extended surface receivers were evaluated. The windowed matrix receiver proved to offer substantial cost and performance benefits. An efficient and cost effective hardware design was evaluated for a receiver which can be readily interfaced to fuel and chemical processes or to heat engines for power generation.

  19. Performance testing of lidar receivers

    NASA Technical Reports Server (NTRS)

    Shams, M. Y.

    1986-01-01

    In addition to the considerations about the different types of noise sources, dynamic range, and linearity of a lidar receiver, one requires information about the pulse shape retaining capabilities of the receiver. For this purpose, relatively precise information about the height resolution as well as the recovery time of the receiver, due both to large transients and to fast changes in the received signal, is required. As more and more analog receivers using fast analog to digital converters and transient recorders will be used in the future lidar systems, methods to test these devices are essential. The method proposed for this purpose is shown. Tests were carried out using LCW-10, LT-20, and FTVR-2 as optical parts of the optical pulse generator circuits. A commercial optical receiver, LNOR, and a transient recorder, VK 220-4, were parts of the receiver system.

  20. Bragg-cell receiver study

    NASA Technical Reports Server (NTRS)

    Wilson, Lonnie A.

    1987-01-01

    Bragg-cell receivers are employed in specialized Electronic Warfare (EW) applications for the measurement of frequency. Bragg-cell receiver characteristics are fully characterized for simple RF emitter signals. This receiver is early in its development cycle when compared to the IFM receiver. Functional mathematical models are derived and presented in this report for the Bragg-cell receiver. Theoretical analysis is presented and digital computer signal processing results are presented for the Bragg-cell receiver. Probability density function analysis are performed for output frequency. Probability density function distributions are observed to depart from assumed distributions for wideband and complex RF signals. This analysis is significant for high resolution and fine grain EW Bragg-cell receiver systems.

  1. Optical Receivers With Rough Reflectors

    NASA Technical Reports Server (NTRS)

    Vilnrotter, Victor A.

    1989-01-01

    Receiver for optical communications uses rough reflector instead of diffraction-limited reflector customarily thought necessary for such systems. Rough reflector collects and focuses optical signal. Other receiver components include narrow-passband optical filter to reject out-of-band background radiation, spatial filter to limit receiver field of view, optical-detector array (typically two concentric detectors), and postdetection processor to reconstruct transmitted message.

  2. Frequency Diverse Array Receiver Architectures

    DTIC Science & Technology

    2015-06-29

    Frequency Diverse Array Receiver Architectures A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science in...VISION BY AaronM. Jones ENTITLED Frequency Diverse Array Receiver Architectures BE ACCEPTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF...M.S.Egr, Department of Electrical Engineering and Computer Science, Wright State University, 2011. Frequency Diverse Array Receiver Architectures

  3. Low cost omega navigation receiver

    NASA Technical Reports Server (NTRS)

    Lilley, R. W.

    1974-01-01

    The development of a low cost Omega navigation receiver is discussed. Emphasis is placed on the completion and testing of a modular, multipurpose Omega receiver which utilizes a digital memory-aided, phase-locked loop to provide phase measurement data to a variety of applications interfaces. The functional units contained in the prototype device are described. The receiver is capable of receiving and storing phase measurements for up to eight Omega signals and computes two switch-selectable lines of position, displaying this navigation data in chart-recorded form.

  4. Receiver System Analysis and Optimization

    DTIC Science & Technology

    2013-01-01

    True Top-Down Design Methodology .................................. 5 Figure 4. Generic 16- QAM direct-conversion receiver...ADC 16- QAM decoder Figure 4. Generic 16- QAM direct-conversion receiver Complex digitally generated signals defy traditional spreadsheet...Intercept Point Three QAM Quadrature Amplitude Modulation SNR Signal-to-Noise Ratio USAF USR VCO United States Air Force Upsampling Ratio Voltage Controlled Oscillator

  5. UWB delay and multiply receiver

    DOEpatents

    Dallum, Gregory E.; Pratt, Garth C.; Haugen, Peter C.; Romero, Carlos E.

    2013-09-10

    An ultra-wideband (UWB) delay and multiply receiver is formed of a receive antenna; a variable gain attenuator connected to the receive antenna; a signal splitter connected to the variable gain attenuator; a multiplier having one input connected to an undelayed signal from the signal splitter and another input connected to a delayed signal from the signal splitter, the delay between the splitter signals being equal to the spacing between pulses from a transmitter whose pulses are being received by the receive antenna; a peak detection circuit connected to the output of the multiplier and connected to the variable gain attenuator to control the variable gain attenuator to maintain a constant amplitude output from the multiplier; and a digital output circuit connected to the output of the multiplier.

  6. Customizable Digital Receivers for Radar

    NASA Technical Reports Server (NTRS)

    Moller, Delwyn; Heavey, Brandon; Sadowy, Gregory

    2008-01-01

    Compact, highly customizable digital receivers are being developed for the system described in 'Radar Interferometer for Topographic Mapping of Glaciers and Ice Sheets' (NPO-43962), NASA Tech Briefs, Vol. 31, No. 7 (August 2007), page 72. The receivers are required to operate in unison, sampling radar returns received by the antenna elements in a digital beam-forming (DBF) mode. The design of these receivers could also be adapted to commercial radar systems. At the time of reporting the information for this article, there were no commercially available digital receivers capable of satisfying all of the operational requirements and compact enough to be mounted directly on the antenna elements. A provided figure depicts the overall system of which the digital receivers are parts. Each digital receiver includes an analog-to-digital converter (ADC), a demultiplexer (DMUX), and a field-programmable gate array (FPGA). The ADC effects 10-bit band-pass sampling of input signals having frequencies up to 3.5 GHz. The input samples are demultiplexed at a user-selectable rate of 1:2 or 1:4, then buffered in part of the FPGA that functions as a first-in/first-out (FIFO) memory. Another part of the FPGA serves as a controller for the ADC, DMUX, and FIFO memory and as an interface between (1) the rest of the receiver and (2) a front-panel data port (FPDP) bus, which is an industry-standard parallel data bus that has a high data-rate capability and multichannel configuration suitable for DBF. Still other parts of the FPGA in each receiver perform signal-processing functions. The digital receivers can be configured to operate in a stand-alone mode, or in a multichannel mode as needed for DBF. The customizability of the receiver makes it applicable to a broad range of system architectures. The capability for operation of receivers in either a stand-alone or a DBF mode enables the use of the receivers in an unprecedentedly wide variety of radar systems.

  7. An NNSS satellite timing receiver

    NASA Technical Reports Server (NTRS)

    Jain, C. L.; Kumar, K.; Andharia, H. I.; Singh, M.; Dsouza, V.; Goel, V. K.; Sisodia, A. K.

    1982-01-01

    The U.S. Navy Navigation Satellite System, NNSS, offers a unique worldwide facility for precise time synchronization. Space Applications Centre (SAC) developed a simple timing receiver. Using this timing receiver first the internal time consistency of NNSS was studied and then its performance to synchronize time was compared with that of National Time Standard. The methodology of data analysis, results, and various sources of error which affect the time transfer accuracy were studied and described. The main source of error was found to be the receiver delay which varies with signal strength. It is possible to apply that this delay correction empirically provided signal strength is recorded.

  8. Stevenson received the Whipple award

    NASA Astrophysics Data System (ADS)

    Shoemaker, Eugene M.; Stevenson, David J.

    1996-02-01

    David J. Stevenson received the Whipple Award at the 1994 Spring Meeting in Baltimore. The award is given for outstanding scientific contributions to the field of planetology. The citation and Stevenson's response are given here.

  9. Coe Receives 2007 Gilbert Award

    NASA Astrophysics Data System (ADS)

    Bogue, Scott W.; Coe, Robert S.

    2008-05-01

    Robert S. Coe received the 2007 William Gilbert Award at the 2007 AGU Fall Meeting in San Francisco, Calif. The award recognizes outstanding and unselfish work in magnetism of Earth materials and of the Earth and planets.

  10. Direct Absorption Receiver flow experiments

    NASA Astrophysics Data System (ADS)

    Chavez, J. M.; Tyner, C. E.; Couch, W. A.

    1987-09-01

    In a solar central receiver system Direct Absorption Receiver (DAR), the heat absorbing fluid (a blackened molten nitrate salt) flows in a thin film down a vertical panel (rather than through tubes as in conventional receiver designs) and absorbs the concentrated solar flux directly. To better understand flow phenomena in this type of receiver, we are conducting flow tests using water (because its flow properties are similar to molten salt) and a 3 MWt solar-heated DAR panel research experiment using salt. In this paper we discuss the results of the water flow testing, including manifold development, film stability, wave phenomena, and wind and natural convection effects on flow. In addition, we describe the design of the panel research experiment and planned testing.

  11. Streak camera receiver definition study

    NASA Technical Reports Server (NTRS)

    Johnson, C. B.; Hunkler, L. T., Sr.; Letzring, S. A.; Jaanimagi, P.

    1990-01-01

    Detailed streak camera definition studies were made as a first step toward full flight qualification of a dual channel picosecond resolution streak camera receiver for the Geoscience Laser Altimeter and Ranging System (GLRS). The streak camera receiver requirements are discussed as they pertain specifically to the GLRS system, and estimates of the characteristics of the streak camera are given, based upon existing and near-term technological capabilities. Important problem areas are highlighted, and possible corresponding solutions are discussed.

  12. Solar dynamic heat receiver technology

    NASA Technical Reports Server (NTRS)

    Sedgwick, Leigh M.

    1991-01-01

    A full-size, solar dynamic heat receiver was designed to meet the requirements specified for electrical power modules on the U.S. Space Station, Freedom. The heat receiver supplies thermal energy to power a heat engine in a closed Brayton cycle using a mixture of helium-xenon gas as the working fluid. The electrical power output of the engine, 25 kW, requires a 100 kW thermal input throughout a 90 minute orbit, including when the spacecraft is eclipsed for up to 36 minutes from the sun. The heat receiver employs an integral thermal energy storage system utilizing the latent heat available through the phase change of a high-temperature salt mixture. A near eutectic mixture of lithium fluoride and calcium difluoride is used as the phase change material. The salt is contained within a felt metal matrix which enhances heat transfer and controls the salt void distribution during solidification. Fabrication of the receiver is complete and it was delivered to NASA for verification testing in a simulated low-Earth-orbit environment. This document reviews the receiver design and describes its fabrication history. The major elements required to operate the receiver during testing are also described.

  13. PPM Receiver Implemented in Software

    NASA Technical Reports Server (NTRS)

    Gray, Andrew; Kang, Edward; Lay, Norman; Vilnrotter, Victor; Srinivasan, Meera; Lee, Clement

    2010-01-01

    A computer program has been written as a tool for developing optical pulse-position- modulation (PPM) receivers in which photodetector outputs are fed to analog-to-digital converters (ADCs) and all subsequent signal processing is performed digitally. The program can be used, for example, to simulate an all-digital version of the PPM receiver described in Parallel Processing of Broad-Band PPM Signals (NPO-40711), which appears elsewhere in this issue of NASA Tech Briefs. The program can also be translated into a design for digital PPM receiver hardware. The most notable innovation embodied in the software and the underlying PPM-reception concept is a digital processing subsystem that performs synchronization of PPM time slots, even though the digital processing is, itself, asynchronous in the sense that no attempt is made to synchronize it with the incoming optical signal a priori and there is no feedback to analog signal processing subsystems or ADCs. Functions performed by the software receiver include time-slot synchronization, symbol synchronization, coding preprocessing, and diagnostic functions. The program is written in the MATLAB and Simulink software system. The software receiver is highly parameterized and, hence, programmable: for example, slot- and symbol-synchronization filters have programmable bandwidths.

  14. UWB communication receiver feedback loop

    DOEpatents

    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.

  15. Receiver-exciter controller design

    NASA Technical Reports Server (NTRS)

    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.

  16. Central solar-energy receiver

    DOEpatents

    Not Available

    1981-10-27

    An improved tower-mounted central solar energy receiver for heating air drawn through the receiver by an induced draft fan is described. A number of vertically oriented, energy absorbing, fin-shaped slats are radially arranged in a number of concentric cylindrical arrays on top of the tower coaxially surrounding a pipe having air holes through which the fan draws air which is heated by the slats which receive the solar radiation from a heliostat field. A number of vertically oriented and wedge-shaped columns are radially arranged in a number of concentric cylindrical clusters surrounding the slat arrays. The columns have two mirror-reflecting sides to reflect radiation into the slat arrays and one energy absorbing side to reduce reradiation and reflection from the slat arrays.

  17. Annular solar receiver thermal characteristics

    NASA Astrophysics Data System (ADS)

    Ratzel, A. C.; Sisson, C. E.

    1980-10-01

    Results from thermal studies performed for an annular solar receiver assembly to be used with the 2 m, 90 deg parabolic collector trough are presented. The receiver configuration modeled consists of a 2.54 cm o.d. steel tube with a black chrome selective surface and an enclosing concentric Pyrex glass envelope. Previous thermal work conducted on the parabolic cylindrical collector design established the geometry and solar noon absorbed flux distribution used. One and two dimensional thermal models were developed to provide receiver assembly temperatures, heat losses, and working fluid energy extraction data with the Therminol-66 (T-66) bulk temperature maintained at 315 C. Parameters varied in the work include wind velocity, ambient air temperature, annulus gas pressure, and T-66 flow condition (Reynolds number). Heat loss and energy extraction results are tabulated and temperature distributions from two dimensional thermal modeling are graphically presented.

  18. Digital Receiver for Microwave Radiometry

    NASA Technical Reports Server (NTRS)

    Ellingson, Steven W.; Hampson, Grant A.; Johnson, Joel T.

    2005-01-01

    A receiver proposed for use in L-band microwave radiometry (for measuring soil moisture and sea salinity) would utilize digital signal processing to suppress interfering signals. Heretofore, radio frequency interference has made it necessary to limit such radiometry to a frequency band about 20 MHz wide, centered at .1,413 MHz. The suppression of interference in the proposed receiver would make it possible to expand the frequency band to a width of 100 MHz, thereby making it possible to obtain greater sensitivity and accuracy in measuring moisture and salinity

  19. Organic Rankine cycle receiver development

    NASA Technical Reports Server (NTRS)

    Haskins, H. J.

    1981-01-01

    The selected receiver concept is a direct-heated, once-through, monotube boiler operated at supercritical pressure. The cavity is formed by a cylindrical copper shell and backwall, with stainless steel tubing brazed to the outside surface. This core is surrounded by lightweight refractory insulation, load-bearing struts, and an outer case. The aperture plate is made of copper to provide long life by conduction and reradiation of heat away from the aperture lip. The receiver thermal efficiency is estimated to be 97 percent at rated conditions (energy transferred to toluene divided by energy incident on aperture opening). Development of the core manufacturing and corrosion protection methods is complete.

  20. The GBT 4mm Receiver

    NASA Astrophysics Data System (ADS)

    Frayer, David T.; White, S.; Watts, G.; Stennes, M.; Maddalena, R. J.; Simon, R.; Pospieszalski, M.; Bryerton, E.

    2013-01-01

    The new 4mm receiver (67--93 GHz) for the Robert C. Byrd Green Bank Telescope (GBT) was built to take advantage of the improved surface accuracy of the dish. The low frequency end of the 3mm atmospheric window is not available with ALMA (<84 GHz), and the sensitivity of the GBT is better than any other facility within this band. We discuss the design and performance of this new receiver for the GBT, and highlight the science opportunities available with the instrument. The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc.

  1. Advances in SIS receiver technology

    NASA Technical Reports Server (NTRS)

    Frerking, M. A.

    1988-01-01

    Significant advances in SIS receiver technology since the last Asilomar meeting include: superconductor materials, integrated inductive tuning elements, and planar mounting structures. The effect of these advances is to push the upper frequency operating limit from about 600 to 1500 GHz, and to enhance the feasibility of focal plane arrays of heterodyne receivers. A fundamental high frequency operating limit of SIS mixers is set by the superconducting energy gap. A practical limitation for high frequency operation of SIS junctions is their parasitic capacitance and resistance. The performance of the mixer will be degraded by the Resistor-Capacitor rolloff. Several designs were reported for inductive elements integrated on the same substrate as the SIS junctions to tune out the bulk junction capacitance. Most millimeter SIS-based heterodyne receivers have used waveguide coupling structures. Technology has advanced to the state where programs that have a high probability of success can be defined to produce arrays of SIS receivers for frequencies as high as 1500 GHz.

  2. Microwave blackbodies for spaceborne receivers

    NASA Technical Reports Server (NTRS)

    Stacey, J. M.

    1985-01-01

    The properties of microwave blackbody targets are explained as they apply to the calibration of spaceborne receivers. Also described are several practicable, blackbody targets used to test and calibrate receivers in the laboratory and in the thermal vacuum chamber. Problems with the precision and the accuracy of blackbody targets, and blackbody target design concepts that overcome some of the accuracy limitations present in existing target designs, are presented. The principle of the Brewster angle blackbody target is described where the blackbody is applied as a fixed-temperature test target in the laboratory and as a variable-temperature target in the thermal vacuum chamber. The reflectivity of a Brewster angle target is measured in the laboratory. From this measurement, the emissivity of the target is calculated. Radiatively cooled thermal suspensions are discussed as the coolants of blackbody targets and waveguide terminations that function as calibration devices in spaceborne receivers. Examples are given for the design of radiatively cooled thermal suspensions. Corrugated-horn antennas used to observe the cosmic background and to provide a cold-calibration source for spaceborne receivers are described.

  3. RFID receiver apparatus and method

    DOEpatents

    Scott, Jeffrey Wayne [Pasco, WA

    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.

  4. Vergano Receives David Perlman Award

    NASA Astrophysics Data System (ADS)

    Kelly, Sue

    2006-08-01

    Dan Vergano received the Perlman Award at the Joint Assembly Honors Ceremony, whichwas held on 25 May 2006 in Baltimore, Md. Vergano was honored for `The Debate's over:Globe is warming,' which describes the linkages between the science of climate change andthe complexity of technical and economic decisions facing its mitigation.

  5. Converting accounts receivable into cash.

    PubMed

    Folk, M D; Roest, P R

    1995-09-01

    In recent years, increasing numbers of healthcare providers have converted their accounts receivable into cash through a process called securitization. This practice has gained popularity because it provides a means to raise capital necessary to healthcare organizations. Although securitization transactions can be complex, they may provide increased financial flexibility to providers as they prepare for continuing change in the healthcare industry.

  6. Clark Receives Ocean Sciences Award

    NASA Astrophysics Data System (ADS)

    Roman, Michael R.; Clark, H. Lawrence

    2008-09-01

    H. Lawrence Clark received the 2008 Ocean Sciences Award at the 2008 Ocean Sciences Meeting, held 2-7 March 2008 in Orlando, Fla. The award is given in recognition of outstanding and long-standing service to the ocean sciences.

  7. Receiver Operating Characteristic (ROC) Analysis

    ERIC Educational Resources Information Center

    Krupinski, Elizabeth A.

    2017-01-01

    Visual expertise covers a broad range of types of studies and methodologies. Many studies incorporate some measure(s) of observer performance or how well participants perform on a given task. Receiver Operating Characteristic (ROC) analysis is a method commonly used in signal detection tasks (i.e., those in which the observer must decide whether…

  8. FQPSK-B viterbi receiver

    NASA Technical Reports Server (NTRS)

    Lee, Dennis K. (Inventor); Simon, Marvin K. (Inventor); Yan, Tsun-Yee (Inventor)

    2006-01-01

    An FQPSK-B receiver uses a simplified trellis system which uses combinations of FQPSK-B waveforms to correlate against an input signal. This enables reduction of the number of correlators that are used and the number of comparisons that are made by the correlators.

  9. Today's central receiver power plant

    NASA Astrophysics Data System (ADS)

    Alpert, D. J.; Kolb, G. J.; Chavez, J. M.

    1991-04-01

    For 15 years, the United States Department of Energy has worked with industry, both utilities and manufacturers, to develop the technology of solar central receiver power plants. In this type of plant, sunlight is concentrated by a field of sun-tracking mirrors, called heliostats, onto a centrally located receiver. The solar energy is collected in the form of a heated fluid, which is used to generate steam to power a conventional turbine generator. For a number of reasons, molten nitrate salt is now the preferred heat transfer fluid. Commercial plants will be sized between 100 and 200 MW. The impetus for developing central receivers comes from their unique advantages: (1) they produce clean, reliable, low-cost electricity; (2) they have practical energy storage that provides a high degree of dispatchability (annually up to 60 percent) - without fossil fuels; and (3) they are environmentally benign. Development efforts around the world have brought the technology to the brink of commercialization: The technical feasibility has been proven, and cost, performance, and reliability can be confidently predicted. Plans are currently being developed for the final steps toward commercial central receiver power plants.

  10. Femtosecond Photon-Counting Receiver

    NASA Technical Reports Server (NTRS)

    Krainak, Michael A.; Rambo, Timothy M.; Yang, Guangning; Lu, Wei; Numata, Kenji

    2016-01-01

    An optical correlation receiver is described that provides ultra-precise distance and/or time-pulse-width measurements even for weak (single photons) and short (femtosecond) optical signals. A new type of optical correlation receiver uses a fourth-order (intensity) interferometer to provide micron distance measurements even for weak (single photons) and short (femtosecond) optical signals. The optical correlator uses a low-noise-integrating detector that can resolve photon number. The correlation (range as a function of path delay) is calculated from the variance of the photon number of the difference of the optical signals on the two detectors. Our preliminary proof-of principle data (using a short-pulse diode laser transmitter) demonstrates tens of microns precision.

  11. Scintillation-Hardened GPS Receiver

    NASA Technical Reports Server (NTRS)

    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.

  12. 30 GHz Commercial Satellite Receivers

    NASA Technical Reports Server (NTRS)

    Kerczewski, Robert J.; Ponchak, George E.; Romanofsky, Robert R.

    1989-01-01

    NASA's research and development work in satellite communications for the past 10 years has included a major technology thrust aimed at opening the Ka frequency band to commercial exploitation. This has included the development and testing of advanced system network architectures, on-board switching and processing, multibeam and phased array antennas, and satellite and ground terminal RF and digital hardware. Development work in system hardware has focused on critical components including power amplifiers, satellite IF switch matrices, low noise receivers, baseband processors, and high data rate bandwidth efficient modems. This paper describes NASA's work in developing and testing 30 GHz low noise satellite receivers for commercial space communications uplink applications. Frequencies allotted for fixed service commercial satellite communications in the Ka band are 27.5 - 30.0 GHz for uplink transmission and 17.7 - 20.2 GHz for downlink transmission. The relatively large 2.5 GHz bandwidth lends itself to wideband, high data rate digital transmission applications.

  13. SAW correlator spread spectrum receiver

    DOEpatents

    Brocato, Robert W

    2014-04-01

    A surface acoustic wave (SAW) correlator spread-spectrum (SS) receiver is disclosed which utilizes a first demodulation stage with a chip length n and a second demodulation stage with a chip length m to decode a transmitted SS signal having a code length l=n.times.m which can be very long (e.g. up to 2000 chips or more). The first demodulation stage utilizes a pair of SAW correlators which demodulate the SS signal to generate an appropriate code sequence at an intermediate frequency which can then be fed into the second demodulation stage which can be formed from another SAW correlator, or by a digital correlator. A compound SAW correlator comprising two input transducers and a single output transducer is also disclosed which can be used to form the SAW correlator SS receiver, or for use in processing long code length signals.

  14. Femtosecond photon-counting receiver

    NASA Astrophysics Data System (ADS)

    Krainak, Michael A.; Rambo, Timothy M.; Yang, Guangning; Lu, Wei; Numata, Kenji

    2016-05-01

    An optical correlation receiver is described that provides ultra-precise distance and/or time/pulsewidth measurements even for weak (single photons) and short (femtosecond) optical signals. A new type of optical correlation receiver uses a fourth-order (intensity) interferometer to provide micron distance measurements even for weak (single photons) and short (femtosecond) optical signals. The optical correlator uses a low-noise-integrating detector that can resolve photon number. The correlation (range as a function of path delay) is calculated from the variance of the photon number of the difference of the optical signals on the two detectors. Our preliminary proof-of principle data (using a short-pulse diode laser transmitter) demonstrates tens of microns precision.

  15. Femtosecond Photon-Counting Receiver

    NASA Technical Reports Server (NTRS)

    Krainak, Michael A.; Rambo, Timothy M.; Yang, Guangning; Lu, Wei; Numata, Kenji

    2016-01-01

    An optical correlation receiver is described that provides ultra-precise distance and/or time/pulse-width measurements even for weak (single photons) and short (femtosecond) optical signals. A new type of optical correlation receiver uses a fourth-order (intensity) interferometer to provide micron distance measurements even for weak (single photons) and short (femtosecond) optical signals. The optical correlator uses a low-noise-integrating detector that can resolve photon number. The correlation (range as a function of path delay) is calculated from the variance of the photon number of the difference of the optical signals on the two detectors. Our preliminary proof-of principle data (using a short-pulse diode laser transmitter) demonstrates tens of microns precision.

  16. Thompson receives 1994 Bowen award

    NASA Astrophysics Data System (ADS)

    Green, David H.; Thompson, Alan Bruce

    At the Spring Meeting in Baltimore, May 23, 1994, Alan Bruce Thompson of the Eidgenossiche Technische Hochschule, Zurich, received the 1994 N. L. Bowen Award of the Volcanology, Geochemsitry, and Petrology section, which is given for a single outstanding contribution to volcanology, geochemistry, or petrology made during the preceding 5 years. The award was presented by David H. Green of the Research School of Earth Sciences. The citation and response are given here.

  17. Scanned Laser Illuminator/Receiver

    DTIC Science & Technology

    1976-11-01

    matching high sensitivity, high resolution receiver. A CW- pumped Nd:YAG laser operated in a pulsed mode and providing a fan-shaped illumination beam...greatly improve the linearity of the scanner and to permit variable scan rate (non-resonant) operation. A cw- pumped NdiYAG laser is used as the...illustrate parallel development of the PIN diode /CCD sensor hybrid and the 100W laser . Al- though a detailed cost analysis for procurement of this large

  18. Managing Medicare receivables after PIP.

    PubMed

    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.

  19. Digital-data receiver synchronization

    DOEpatents

    Smith, Stephen F.; Turner, Gary W.

    2005-08-02

    Digital-data receiver synchronization is provided with composite phase-frequency detectors, mutually cross-connected comparison feedback or both to provide robust reception of digital data signals. A single master clock can be used to provide frequency signals. Advantages can include fast lock-up time in moderately to severely noisy conditions, greater tolerance to noise and jitter when locked, and improved tolerance to clock asymmetries.

  20. Integrated optical vortex beam receivers.

    PubMed

    Cicek, Kenan; Hu, Ziyang; Zhu, Jiangbo; Meriggi, Laura; Li, Shimao; Nong, Zhichao; Gao, Shengqian; Zhang, Ning; Wang, Xuyang; Cai, Xinlun; Sorel, Marc; Yu, Siyuan

    2016-12-12

    A simple and ultra-compact integrated optical vortex beam receiver device is presented. The device is based on the coupling between the optical vortex modes and whispering gallery modes in a micro-ring resonator via embedded angular gratings, which provides the selective reception of optical vortex modes with definitive total angular momentum (summation of spin and orbital angular momentum) through the phase matching condition in the coupling process. Experimental characterization confirms the correct detection of the total angular momentum carried by the vortex beams incident on the device. In addition, photonic spin-controlled unidirectional excitation of whispering-gallery modes in the ring receiver is also observed, and utilized to differentiate between left- and right-circular polarizations and therefore unambiguously identify the orbital angular momentum of incident light. Such characteristics provide an effective mode-selective receiver for the eigen-modes in orbital angular momentum fiber transmission where the circularly polarized OAM modes can be used as data communications channels in multiplexed communications or as photonic states in quantum information applications.

  1. RF spectrometers for heterodyne receivers

    NASA Technical Reports Server (NTRS)

    Buhl, D.; Mumma, M. J.

    1980-01-01

    Several types of spectrometers developed for radio astronomy receivers which utilize RF filters, multiple oscillators and mixers, digital autocorrelators and acoustic/optic devices are considered. The RF spectrometer developed at GSFC to provide wide bandwidths (greater than 1 GHz) as well as high resolution (5MHz) is described. The 128 channel filter bank is divided into high and low resolution sections. The high resolution section is tunable by providing a second mixer ahead of the filter bank. This is necessary because infrared receivers which use gas lasers as local oscillators are only tunable to specific laser frequencies. To compensate for astronomical Doppler shifts and molecule frequency differences a second local oscillator and mixer is needed. A diagram of the RF section of the filter bank is shown. The RF spectrometer is shown to be the best means of achieving ultra-wide bandwidths for infrared heterodyne receivers. For high resolution with a large number of channels, the acousto/optical spectrometer is the principle instrument, particularly for balloon or space flight applications.

  2. Measuring and monitoring quality in accounts receivable.

    PubMed

    Jupp, D A

    1987-09-01

    Traditionally, billing activities and accounts receivable have been monitored using days in accounts receivable, an accepted measure of performance. Unfortunately, days in accounts receivables does not measure the quality of the receivable cycle--important to receivables performance and turnaround. By developing a system of quality measurement for the receivable cycle, the financial manager is able to identify financial risk, submit an accurate claim, and reduce the need for costly follow-up activity, improving receivables performance for the hospital.

  3. Integrated terahertz transmitters and receivers

    NASA Astrophysics Data System (ADS)

    Crowe, Thomas W.; Porterfield, David W.; Hesler, Jeffrey L.; Bishop, William L.; Kurtz, David S.

    2004-02-01

    Through a US Army sponsored SBIR project we are developing terahertz components based on integrated GaAs Schottky diodes for the frequency range from 200 - 700 GHz. These new components are inherently broadband and therefore require no mechanical tuners. Rather, they can be electronically swept across significant frequency bands and are therefore useful for chemical and biological spectroscopy. This talk will focus on our demonstration of a terahertz frequency Transmit / Receive capability which may be of use for CB detection and secure communications.

  4. Helping dentists manage accounts receivable.

    PubMed

    Scott, J

    2001-01-01

    First Pacific Corporation (FPC) has worked with dental practices since 1961, providing personal services that optimize practice performance. In addition to being the premier service provider for administrative tasks in dental offices, they supply state-of-the-art hardware and accounts receivable management software. FPC designs and teaches practice development strategies, deliver on-site training, and much more. FPC is dedicated to the long-term professional success of dental clients, their staff, and their practices through a unique, integrated package of services. As a family-owned business, with headquarters in Salem, Oregon, FPC employs approximately two hundred staff who serve practices in twenty-two states.

  5. Digital receiver study and implementation

    NASA Technical Reports Server (NTRS)

    Fogle, D. A.; Lee, G. M.; Massey, J. C.

    1972-01-01

    Computer software was developed which makes it possible to use any general purpose computer with A/D conversion capability as a PSK receiver for low data rate telemetry processing. Carrier tracking, bit synchronization, and matched filter detection are all performed digitally. To aid in the implementation of optimum computer processors, a study of general digital processing techniques was performed which emphasized various techniques for digitizing general analog systems. In particular, the phase-locked loop was extensively analyzed as a typical non-linear communication element. Bayesian estimation techniques for PSK demodulation were studied. A hardware implementation of the digital Costas loop was developed.

  6. Stennis group receives NESC award

    NASA Technical Reports Server (NTRS)

    2009-01-01

    The NASA Engineering & Safety Center recently presented its Group Achievement Award to a Stennis team in recognition of technical excellence in evaluating the operational anomalies and reliability improvements associated with the space shuttle engine cut-off system. Stennis employees receiving the award were: (standing, l to r) Freddie Douglas (NASA), George Drouant (Jacobs Technology Inc.), Fred Abell (Jacobs), Robert Drackett (Jacobs) and Mike Smiles (NASA); (seated, l to r): Binh Nguyen (Jacobs), Stennis Director Gene Goldman and Joseph Lacker (NASA). Phillip Hebert of NASA is not pictured.

  7. Stennis group receives NESC award

    NASA Image and Video Library

    2009-04-14

    The NASA Engineering & Safety Center recently presented its Group Achievement Award to a Stennis team in recognition of technical excellence in evaluating the operational anomalies and reliability improvements associated with the space shuttle engine cut-off system. Stennis employees receiving the award were: (standing, l to r) Freddie Douglas (NASA), George Drouant (Jacobs Technology Inc.), Fred Abell (Jacobs), Robert Drackett (Jacobs) and Mike Smiles (NASA); (seated, l to r): Binh Nguyen (Jacobs), Stennis Director Gene Goldman and Joseph Lacker (NASA). Phillip Hebert of NASA is not pictured.

  8. Recommendations for Use of Meningococcal Conjugate Vaccines in HIV-Infected Persons - Advisory Committee on Immunization Practices, 2016.

    PubMed

    MacNeil, Jessica R; Rubin, Lorry G; Patton, Monica; Ortega-Sanchez, Ismael R; Martin, Stacey W

    2016-11-04

    At its June 2016 meeting, the Advisory Committee on Immunization Practices (ACIP) recommended routine use of meningococcal conjugate vaccine (serogroups A, C, W, and Y; including MenACWY-D [Menactra, Sanofi Pasteur] or MenACWY-CRM [Menveo, GlaxoSmithKline]) for persons aged ≥2 months with human immunodeficiency virus (HIV) infection. ACIP has previously recommended routine vaccination of persons aged ≥2 months who have certain medical conditions that increase risk for meningococcal disease (1), including persons who have persistent (e.g., genetic) deficiencies in the complement pathway (e.g., C3, properdin, Factor D, Factor H, or C5-C9); persons receiving eculizumab (Soliris, Alexion Pharmaceuticals) for treatment of atypical hemolytic uremic syndrome or paroxysmal nocturnal hemoglobinuria (because the drug binds C5 and inhibits the terminal complement pathway); and persons with functional or anatomic asplenia (including persons with sickle cell disease). Routine vaccination with meningococcal conjugate vaccine is also recommended for all healthy adolescents in the United States (1). This report summarizes the evidence considered by ACIP in recommending vaccination for HIV-infected persons, and provides recommendations and guidance for use of meningococcal conjugate vaccines (serogroups A, C, W, and Y) among HIV-infected persons aged ≥2 months; the majority of meningococcal disease among HIV-infected persons is caused by these four serogroups.

  9. Optimization of MLS receivers for multipath environments

    NASA Technical Reports Server (NTRS)

    Mcalpine, G. A.; Highfill, J. H., III; Tzeng, C. P. J.; Koleyni, G.

    1978-01-01

    Reduced order receiver (suboptimal receiver) analysis in multipath environments is presented. The origin and objective of MLS is described briefly. Signal modeling in MLS the optimum receiver is also included and a description of a computer oriented technique which was used in the simulation study of the suboptimal receiver is provided. Results and conclusion obtained from the research for the suboptimal receiver are reported.

  10. Front end for GPS receivers

    NASA Technical Reports Server (NTRS)

    Thomas, Jr., Jess Brooks (Inventor)

    1999-01-01

    The front end in GPS receivers has the functions of amplifying, down-converting, filtering and sampling the received signals. In the preferred embodiment, only two operations, A/D conversion and a sum, bring the signal from RF to filtered quadrature baseband samples. After amplification and filtering at RF, the L1 and L2 signals are each sampled at RF at a high selected subharmonic rate. The subharmonic sample rates are approximately 900 MHz for L1 and 982 MHz for L2. With the selected subharmonic sampling, the A/D conversion effectively down-converts the signal from RF to quadrature components at baseband. The resulting sample streams for L1 and L2 are each reduced to a lower rate with a digital filter, which becomes a straight sum in the simplest embodiment. The frequency subsystem can be very simple, only requiring the generation of a single reference frequency (e.g. 20.46 MHz minus a small offset) and the simple multiplication of this reference up to the subharmonic sample rates for L1 and L2. The small offset in the reference frequency serves the dual purpose of providing an advantageous offset in the down-converted carrier frequency and in the final baseband sample rate.

  11. Sheeley Receives 2009 Hale Prize

    NASA Astrophysics Data System (ADS)

    Tretkoff, Ernie

    2009-05-01

    Neil Sheeley Jr., of the Space Science Division of the Naval Research Laboratory (NRL), has been awarded the 2009 George Ellery Hale Prize by the Solar Physics Division of the American Astronomical Society (AAS). The international award recognizes work in solar astronomy done over an extended period of time. Sheeley will receive the award in June at the AAS meeting in Pasadena, Calif. Sheeley is cited "for his continuing outstanding contributions to our understanding of the solar magnetic field, coronal holes, and coronal mass ejections. His wide-ranging observational and theoretical work has laid the foundation for much current research in solar and heliospheric physics, and continues to have important applications in space weather prediction."

  12. Preamplifier Noise in VLF Receivers

    NASA Technical Reports Server (NTRS)

    Burhans, R. W.

    1978-01-01

    Noise specifications for junction field-effect transistors are presented in different ways depending on the particular semiconductor manufacturer. Arithmetic involved in converting these specifications to equivalent RMS noise in microvolts developed at the preamplifier input terminal is reviewed. These methods were useful for estimating the noise performance of high input impedance preamplifiers used with E-field antennas operating in the range of 1 KHz to 10 MHz. Both the JFET MPF-102 transistor and the COS/MOS CA3600 transistor array provided amplification for VLF receivers where the internally generated noise was well below the atmospheric noise level. The CA3600 transistor array provided better performance because of the more symmetrical complementary MOS transistor transfer characteristics than a single N-type biased JFET transistor. The CMOS amplifier resulted in self-compensating gain characteristics over a very wide temperature range from -55 to +125 C.

  13. A cryogenic receiver for EPR.

    PubMed

    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.

  14. Lunar Receiving Laboratory Project History

    NASA Technical Reports Server (NTRS)

    Mangus, Susan; Larsen, William

    2004-01-01

    As early as 1959, the Working Group on Lunar Exploration within NASA advocated that 'one of the prime objectives of the first lunar landing mission should be the collection of samples for return to Earth, where they could be subjected to detailed study and analysis.' Within NASA, neither this group nor any other scientists working with the Agency were concerned about back contamination issues. Outside of NASA, back contamination concerns had been raised as early as 1960. Although NASA did not seem to pay any attention to the concerns at that time, the scientific community continued to be interested in the topic. In 1962 and again in 1963, as the Apollo Program loomed large, further discussions were held. These early discussions of back contamination did not make their way into NASA's administration, however, and when Manned Spacecraft Center personnel began to articulate early concepts for the Lunar Receiving Laboratory (LRL), the back contamination issue was not considered. Once this concern became a major focus, however, the LRL's development became increasingly complex. This is the history of that development.

  15. Recent developments in superconducting receivers

    NASA Astrophysics Data System (ADS)

    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. Fluid absorption solar energy receiver

    NASA Technical Reports Server (NTRS)

    Bair, Edward J.

    1993-01-01

    A conventional solar dynamic system transmits solar energy to the flowing fluid of a thermodynamic cycle through structures which contain the gas and thermal energy storage material. Such a heat transfer mechanism dictates that the structure operate at a higher temperature than the fluid. This investigation reports on a fluid absorption receiver where only a part of the solar energy is transmitted to the structure. The other part is absorbed directly by the fluid. By proportioning these two heat transfer paths the energy to the structure can preheat the fluid, while the energy absorbed directly by the fluid raises the fluid to its final working temperature. The surface temperatures need not exceed the output temperature of the fluid. This makes the output temperature of the gas the maximum temperature in the system. The gas can have local maximum temperatures higher than the output working temperature. However local high temperatures are quickly equilibrated, and since the gas does not emit radiation, local high temperatures do not result in a radiative heat loss. Thermal radiation, thermal conductivity, and heat exchange with the gas all help equilibrate the surface temperature.

  17. Recent developments in superconducting receivers

    SciTech Connect

    Richards, P.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.

  18. Development of an Air Brayton solar receiver

    NASA Technical Reports Server (NTRS)

    1980-01-01

    Various receiver configurations and operating conditions were examined. The interface requirements between the receiver/concentrator/power module were addressed. Production cost estimates were obtained to determine the cost of the receiver during the 1980 timeframe. A conceptual design of an air Brayton solar receiver is presented based on the results. The following design goals were established: (1)peak thermal input power - 85 KWt; (2)receiver outlet air temperature - 1500 F; (3)receiver inlet air temperature - 1050 F; (4)design mass flow rate - 0.533 lb/sec; and (5)design receiver inlet pressure - 36.75 psia.

  19. Measuring accounts receivable performance: a comprehensive method.

    PubMed

    Newton, R L

    1993-05-01

    Nonperforming assets, such as accounts receivable, are frequently cited as sources of financial difficulty for hospitals. Yet, many hospitals, relying on the traditional measure of accounts receivable--days revenue outstanding--may not have a true grasp of the real cost of their accounts receivable. The author discusses the costs imposed on a hospital by accounts receivable and describes three cost components that must be calculated if the true cost of accounts receivable is to be determined and controlled.

  20. Thermal resistance model for CSP central receivers

    NASA Astrophysics Data System (ADS)

    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.

  1. Structuring a sound securitization of healthcare receivables.

    PubMed

    Spradling, Mark

    2003-02-01

    Securitization of receivables allows healthcare providers to obtain an additional funding source by selling their accounts receivables to investors. A double-lock-box structure allows providers to securitize Medicare and Medicaid receivables without violating federal laws. A 2001 revision to the Uniform Commercial Code facilitates providers' securitization of private healthcare insurance receivables by underscoring rights of a purchaser of those receivables. HIPAA privacy standards appear to permit the use and disclosure of protected health information in crafting a securitization program. The securitization should be structured to shield the value of the receivables to be transferred from the potential backruptcies of the originator and the purchaser.

  2. Optimization of MLS receivers for multipath environments

    NASA Technical Reports Server (NTRS)

    Mcalpine, G. A.; Irwin, S. H.; NELSON; Roleyni, G.

    1977-01-01

    Optimal design studies of MLS angle-receivers and a theoretical design-study of MLS DME-receivers are reported. The angle-receiver results include an integration of the scan data processor and tracking filter components of the optimal receiver into a unified structure. An extensive simulation study comparing the performance of the optimal and threshold receivers in a wide variety of representative dynamical interference environments was made. The optimal receiver was generally superior. A simulation of the performance of the threshold and delay-and-compare receivers in various signal environments was performed. An analysis of combined errors due to lateral reflections from vertical structures with small differential path delays, specular ground reflections with neglible differential path delays, and thermal noise in the receivers is provided.

  3. Trough Receiver Heat Loss Testing (Presentation)

    SciTech Connect

    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.

  4. High speed receiver for capsule endoscope.

    PubMed

    Woo, S H; Yoon, K W; Moon, Y K; Lee, J H; Park, H J; Kim, T W; Choi, H C; Won, C H; Cho, J H

    2010-10-01

    In this study, a high-speed receiver for a capsule endoscope was proposed and implemented. The proposed receiver could receive 20 Mbps data that was sufficient to receive images with a higher resolution than conventional receivers. The receiver used a 1.2 GHz band to receive radio frequency (RF) signal, and demodulated the signal to an intermediate frequency (IF) stage (150 MHz). The demodulated signal was amplified, filtered, and under-sampled by a high-speed analog-to-digital converter (ADC). In order to decode the under-sampled data in real time, a simple frequency detection algorithm was selected and was implemented by using a FPGA. The implemented system could receive 20 Mbps data.

  5. How To Improve You Shipping and Receiving.

    ERIC Educational Resources Information Center

    Sturgeon, Julie

    2001-01-01

    Discusses how two universities improved their shipping and receiving operations and cut costs. Examples from the University of Texas at Dallas and John Hopkins University, Baltimore, Maryland, illustrate how they established greater shipping and receiving department efficiencies. (GR)

  6. How To Improve You Shipping and Receiving.

    ERIC Educational Resources Information Center

    Sturgeon, Julie

    2001-01-01

    Discusses how two universities improved their shipping and receiving operations and cut costs. Examples from the University of Texas at Dallas and John Hopkins University, Baltimore, Maryland, illustrate how they established greater shipping and receiving department efficiencies. (GR)

  7. Telemetry Tests Of The Advanced Receiver II

    NASA Technical Reports Server (NTRS)

    Hinedi, Sami M.; Bevan, Roland P.; Marina, Miguel

    1993-01-01

    Report describes telemetry tests of Advanced Receiver II (ARX-II): digital radio receiving subsystem operating on intermediate-frequency output of another receiving subsystem called "multimission receiver" (MMR), detecting carrier, subcarrier, and data-symbol signals transmitted by spacecraft, and extracts Doppler information from signals. Analysis of data shows performance of MMR/ARX-II system comparable and sometimes superior to performances of Blk-III/BPA and Blk-III/SDA/SSA systems.

  8. Advanced salt receiver for solar power towers

    SciTech Connect

    Romero, M.; Sanchez, M.; Barrera, G.

    1995-11-01

    Falling Film receivers constitute an alternative to the traditional Salt in Tube receivers, widely used and tested in the Central Receiver Systems. This report presents an innovative concept of Internal Film Receiver (IFR), in which a film made of a eutectic mixture of molten salts flows down the back side of a stainless steel panel. The installation with 550 kW nominal power, molten salt inlet temperature 300 C and outlet temperature 550 C is described.

  9. Automatic Frequency Control For DMSK Receiver

    NASA Technical Reports Server (NTRS)

    Davarian, Faramaz; Sumida, Joe T.

    1989-01-01

    Report discusses performance of automatic frequency-control (AFC) subsystem of differential minimum-shift-keying receiver described in "DMSK Receiver for Moblile/Satellite Service," NPO-16659. Describes efforts to quantify behavior of system during acquisition of carrier signal; including theoretical analysis leading to numerical simulation, and measurements of performance of receiving equipment.

  10. Automatic Frequency Control For DMSK Receiver

    NASA Technical Reports Server (NTRS)

    Davarian, Faramaz; Sumida, Joe T.

    1989-01-01

    Report discusses performance of automatic frequency-control (AFC) subsystem of differential minimum-shift-keying receiver described in "DMSK Receiver for Moblile/Satellite Service," NPO-16659. Describes efforts to quantify behavior of system during acquisition of carrier signal; including theoretical analysis leading to numerical simulation, and measurements of performance of receiving equipment.

  11. 49 CFR 236.730 - Coil, receiver.

    Code of Federal Regulations, 2010 CFR

    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...

  12. Battle Keeps Solar Energy in Receiver

    NASA Technical Reports Server (NTRS)

    Mcdougal, A. R.; Hale, R. R.

    1982-01-01

    Mirror structure in solar concentrator reduces heat loss by reflection and reradiation. Baffle reflects entering rays back and forth in solar-concentrator receiver until they reach heat exchanger. Similarly, infrared energy reradiated by heat exchanger is prevented from leaving receiver. Surfaces of baffle and inside wall of receiver are polished and highly reflective at solar and infrared wavelengths.

  13. Battle Keeps Solar Energy in Receiver

    NASA Technical Reports Server (NTRS)

    Mcdougal, A. R.; Hale, R. R.

    1982-01-01

    Mirror structure in solar concentrator reduces heat loss by reflection and reradiation. Baffle reflects entering rays back and forth in solar-concentrator receiver until they reach heat exchanger. Similarly, infrared energy reradiated by heat exchanger is prevented from leaving receiver. Surfaces of baffle and inside wall of receiver are polished and highly reflective at solar and infrared wavelengths.

  14. A Digital Radio Receiver for Ionospheric Research

    DTIC Science & Technology

    2006-06-01

    of ionospheric structure in 1.1.1 using transmissions from a SuperDARN (SD) transmitter on the ground will call upon mode RRI01. Here the receiver... SuperDARN -ePOP Propagation Experiments with Radio Receiver Instrument HF/VHF Radar e-POP receiver Ionospheric Irregularities Effects of E/F-region density

  15. 49 CFR 393.88 - Television receivers.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 5 2014-10-01 2014-10-01 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 television...

  16. 49 CFR 393.88 - Television receivers.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 5 2013-10-01 2013-10-01 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 television...

  17. 49 CFR 393.88 - Television receivers.

    Code of Federal Regulations, 2010 CFR

    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 television...

  18. 49 CFR 393.88 - Television receivers.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 5 2012-10-01 2012-10-01 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 television...

  19. 49 CFR 393.88 - Television receivers.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 5 2011-10-01 2011-10-01 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 television...

  20. 29 CFR 1910.169 - Air receivers.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 29 Labor 5 2012-07-01 2012-07-01 false Air receivers. 1910.169 Section 1910.169 Labor Regulations... OCCUPATIONAL SAFETY AND HEALTH STANDARDS Compressed Gas and Compressed Air Equipment § 1910.169 Air receivers. (a) General requirements—(1) Application. This section applies to compressed air receivers, and...

  1. 29 CFR 1917.155 - Air receivers.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 7 2011-07-01 2011-07-01 false Air receivers. 1917.155 Section 1917.155 Labor Regulations...) MARINE TERMINALS Related Terminal Operations and Equipment § 1917.155 Air receivers. (a) Application. This section applies to compressed air receivers and equipment used for operations such as...

  2. 29 CFR 1926.306 - Air receivers.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 8 2011-07-01 2011-07-01 false Air receivers. 1926.306 Section 1926.306 Labor Regulations...) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Tools-Hand and Power § 1926.306 Air receivers. (a) General requirements—(1) Application. This section applies to compressed air receivers, and other equipment used...

  3. 29 CFR 1910.169 - Air receivers.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 29 Labor 5 2013-07-01 2013-07-01 false Air receivers. 1910.169 Section 1910.169 Labor Regulations... OCCUPATIONAL SAFETY AND HEALTH STANDARDS Compressed Gas and Compressed Air Equipment § 1910.169 Air receivers. (a) General requirements—(1) Application. This section applies to compressed air receivers, and...

  4. 29 CFR 1926.306 - Air receivers.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 8 2010-07-01 2010-07-01 false Air receivers. 1926.306 Section 1926.306 Labor Regulations...) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Tools-Hand and Power § 1926.306 Air receivers. (a) General requirements—(1) Application. This section applies to compressed air receivers, and other equipment used...

  5. 29 CFR 1910.169 - Air receivers.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 29 Labor 5 2014-07-01 2014-07-01 false Air receivers. 1910.169 Section 1910.169 Labor Regulations... OCCUPATIONAL SAFETY AND HEALTH STANDARDS Compressed Gas and Compressed Air Equipment § 1910.169 Air receivers. (a) General requirements—(1) Application. This section applies to compressed air receivers, and...

  6. 29 CFR 1910.169 - Air receivers.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 5 2010-07-01 2010-07-01 false Air receivers. 1910.169 Section 1910.169 Labor Regulations... OCCUPATIONAL SAFETY AND HEALTH STANDARDS Compressed Gas and Compressed Air Equipment § 1910.169 Air receivers. (a) General requirements—(1) Application. This section applies to compressed air receivers, and...

  7. 29 CFR 1917.155 - Air receivers.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 7 2010-07-01 2010-07-01 false Air receivers. 1917.155 Section 1917.155 Labor Regulations...) MARINE TERMINALS Related Terminal Operations and Equipment § 1917.155 Air receivers. (a) Application. This section applies to compressed air receivers and equipment used for operations such as...

  8. 29 CFR 1926.306 - Air receivers.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 29 Labor 8 2014-07-01 2014-07-01 false Air receivers. 1926.306 Section 1926.306 Labor Regulations...) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Tools-Hand and Power § 1926.306 Air receivers. (a) General requirements—(1) Application. This section applies to compressed air receivers, and other equipment used...

  9. 29 CFR 1926.306 - Air receivers.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 29 Labor 8 2013-07-01 2013-07-01 false Air receivers. 1926.306 Section 1926.306 Labor Regulations...) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Tools-Hand and Power § 1926.306 Air receivers. (a) General requirements—(1) Application. This section applies to compressed air receivers, and other equipment used...

  10. 29 CFR 1910.169 - Air receivers.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 5 2011-07-01 2011-07-01 false Air receivers. 1910.169 Section 1910.169 Labor Regulations... OCCUPATIONAL SAFETY AND HEALTH STANDARDS Compressed Gas and Compressed Air Equipment § 1910.169 Air receivers. (a) General requirements—(1) Application. This section applies to compressed air receivers, and...

  11. 29 CFR 1917.155 - Air receivers.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 29 Labor 7 2012-07-01 2012-07-01 false Air receivers. 1917.155 Section 1917.155 Labor Regulations...) MARINE TERMINALS Related Terminal Operations and Equipment § 1917.155 Air receivers. (a) Application. This section applies to compressed air receivers and equipment used for operations such as...

  12. 29 CFR 1926.306 - Air receivers.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 29 Labor 8 2012-07-01 2012-07-01 false Air receivers. 1926.306 Section 1926.306 Labor Regulations...) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Tools-Hand and Power § 1926.306 Air receivers. (a) General requirements—(1) Application. This section applies to compressed air receivers, and other equipment used...

  13. 29 CFR 1917.155 - Air receivers.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 29 Labor 7 2013-07-01 2013-07-01 false Air receivers. 1917.155 Section 1917.155 Labor Regulations...) MARINE TERMINALS Related Terminal Operations and Equipment § 1917.155 Air receivers. (a) Application. This section applies to compressed air receivers and equipment used for operations such as...

  14. 29 CFR 1917.155 - Air receivers.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 29 Labor 7 2014-07-01 2014-07-01 false Air receivers. 1917.155 Section 1917.155 Labor Regulations...) MARINE TERMINALS Related Terminal Operations and Equipment § 1917.155 Air receivers. (a) Application. This section applies to compressed air receivers and equipment used for operations such as...

  15. A zero-power radio receiver.

    SciTech Connect

    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.

  16. More Efficient Solar Thermal-Energy Receiver

    NASA Technical Reports Server (NTRS)

    Dustin, M. O.

    1987-01-01

    Thermal stresses and reradiation reduced. Improved design for solar thermal-energy receiver overcomes three major deficiencies of solar dynamic receivers described in literature. Concentrator and receiver part of solar-thermal-energy system. Receiver divided into radiation section and storage section. Concentrated solar radiation falls on boiling ends of heat pipes, which transmit heat to thermal-energy-storage medium. Receiver used in number of applications to produce thermal energy directly for use or to store thermal energy for subsequent use in heat engine.

  17. More Efficient Solar Thermal-Energy Receiver

    NASA Technical Reports Server (NTRS)

    Dustin, M. O.

    1987-01-01

    Thermal stresses and reradiation reduced. Improved design for solar thermal-energy receiver overcomes three major deficiencies of solar dynamic receivers described in literature. Concentrator and receiver part of solar-thermal-energy system. Receiver divided into radiation section and storage section. Concentrated solar radiation falls on boiling ends of heat pipes, which transmit heat to thermal-energy-storage medium. Receiver used in number of applications to produce thermal energy directly for use or to store thermal energy for subsequent use in heat engine.

  18. Optimization of MLS receivers for multipath environments

    NASA Technical Reports Server (NTRS)

    Mcalpine, G. A.; Highfill, J. H., III

    1979-01-01

    The angle tracking problems in microwave landing system receivers along with a receiver design capable of optimal performance in the multipath environments found in air terminal areas were studied. Included were various theoretical and evaluative studies like: (1) signal model development; (2) derivation of optimal receiver structures; and (3) development and use of computer simulations for receiver algorithm evaluation. The development of an experimental receiver for flight testing is presented. An overview of the work and summary of principal results and conclusions are reported.

  19. The spectrogram correlation and transformation receiver, revisited.

    PubMed

    Peremans, H; Hallam, J

    1998-08-01

    The spectrogram correlation and transformation (SCAT) receiver has been proposed as a model for the receiver structure used by fm bats. The main contribution of this paper lies in the analysis of which features of the proposed model are responsible for its high accuracy in estimating arrival times of overlapping echoes. Apart from providing an answer to this question, the analysis will also indicate the limitations of the SCAT receiver. In particular, it is shown that the temporal block of the SCAT receiver returns erroneous results for interecho delays < 20 microseconds and for interecho amplitude ratios > 6 dB. It is also shown that the spectral block of the SCAT receiver generates spurious arrival times if more than two overlapping echoes are present. Finally, it is discussed how the characteristic measurement errors predicted by this analysis can be used to further investigate the accuracy of the SCAT receiver as a model of the receiver structure used by fm bats.

  20. Future GOES-R global ground receivers

    NASA Astrophysics Data System (ADS)

    Dafesh, P. A.; Grayver, E.

    2006-08-01

    The Aerospace Corporation has developed an end-to-end testbed to demonstrate a wide range of modern modulation and coding alternatives for future broadcast by the GOES-R Global Rebroadcast (GRB) system. In particular, this paper describes the development of a compact, low cost, flexible GRB digital receiver that was designed, implemented, fabricated, and tested as part of the development. This receiver demonstrates a 10-fold increase in data rate compared to the rate achievable by the current GOES generation, without a major impact on either cost or size. The digital receiver is integrated on a single PCI card with an FPGA device, and analog-to-digital converters. It supports a wide range of modulations (including 8-PSK and 16-QAM) and turbo coding. With appropriate FPGA firmware and software changes, it can also be configured to receive the current (legacy) GOES signals. The receiver has been validated by sending large image files over a high-fidelity satellite channel emulator, including a space-qualified power amplifier and a white noise source. The receiver is a key component of a future GOES-R weather receiver system (also called user terminal) that includes the antenna, low-noise amplifier, downconverter, filters, digital receiver, and receiver system software. This work describes this receiver proof of concept and its application to providing a very credible estimate of the impact of using modern modulation and coding techniques in the future GOES-R system.

  1. High stable remote photoelectric receiver for interferometry

    NASA Astrophysics Data System (ADS)

    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°.

  2. Integration Window Position Estimation in TR Receivers

    SciTech Connect

    Nekoogar, F; Dowla, F; Spiridon, A

    2005-03-15

    Transmitted-reference (TR) receivers avoid the stringent synchronization requirements that exist in conventional pulse detection schemes. However, the performance of such receivers is highly sensitive to precise timing acquisition and tracking as well as the length of their integration window. This window in TR receivers defines the limits of the finite integrator prior to the final decision making block. In this paper, we propose a novel technique that allows us to extract the timing information of the integration window very accurately in UWB-TR receivers in the presence of channel noise. The principles of the method are presented and the BER performance of a modified UWB-TR receiver is investigated by computer simulation. Our studies show that the proposed estimation technique adds value to the conventional TR receiver structure with modest increase in complexity.

  3. Absolute flux density calibrations: Receiver saturation effects

    NASA Technical Reports Server (NTRS)

    Freiley, A. J.; Ohlson, J. E.; Seidel, B. L.

    1978-01-01

    The effect of receiver saturation was examined for a total power radiometer which uses an ambient load for calibration. Extension to other calibration schemes is indicated. The analysis shows that a monotonic receiver saturation characteristic could cause either positive or negative measurement errors, with polarity depending upon operating conditions. A realistic model of the receiver was made by using a linear-cubic voltage transfer characteristic. The evaluation of measurement error for this model provided a means for correcting radio source measurements.

  4. Concentrated solar power generation using solar receivers

    DOEpatents

    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.

  5. Nursing process approach improves receivables management.

    PubMed

    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.

  6. Receiver System: Lessons Learned from Solar Two

    NASA Astrophysics Data System (ADS)

    Litwin, R. Z.

    2002-03-01

    The Boeing Company fabricated the Solar Two receiver as a subcontractor for the Solar Two project. The receiver absorbed sunlight reflected from the heliostat field. A molten-nitrate-salt heat transfer fluid was pumped from a storage tank at grade level, heated from 290 to 565DGC by the receiver mounted on top of a tower, then flowed back down into another storage tank. To make electricity, the hot salt was pumped through a steam generator to produce steam that powered a conventional Rankine steam turbine/generator. This evaluation identifies the most significant Solar Two receiver system lessons learned from the Mechanical Design, Instrumentation and Control, Panel Fabrication, Site Construction, Receiver System Operation, and Management from the perspective of the receiver designer/manufacturer. The lessons learned on the receiver system described here consist of two parts: the Problem and one or more identified Solutions. The appendix summarizes an inspection of the advanced receiver panel developed by Boeing that was installed and operated in the Solar Two receiver.

  7. Wideband infrared receiver backend. [Doppler radar, radiometers

    NASA Technical Reports Server (NTRS)

    Flattau, T.; Mellars, J.

    1974-01-01

    The design, operation, and configuration of the receiver backend for a wideband infrared tracking receiver are described. A squaring loop is incorporated into the receiver design to enable it to track the Doppler shifted carrier which is Phase Shift Keyed modulated. The receiver has a 400 MHz instantaneous bandwidth and tracks signals whose carrier frequency at the backend input is between 200 and 900 MHz with frequency variation rates greater than 20 MHz/second. The output data is compatible with MECL 3 logic.

  8. Receiver System: Lessons Learned From Solar Two

    SciTech Connect

    LITWIN, ROBERT Z.; PACHECO, JAMES E.

    2002-03-01

    The Boeing Company fabricated the Solar Two receiver as a subcontractor for the Solar Two project. The receiver absorbed sunlight reflected from the heliostat field. A molten-nitrate-salt heat transfer fluid was pumped from a storage tank at grade level, heated from 290 to 565 C by the receiver mounted on top of a tower, then flowed back down into another storage tank. To make electricity, the hot salt was pumped through a steam generator to produce steam that powered a conventional Rankine steam turbine/generator. This evaluation identifies the most significant Solar Two receiver system lessons learned from the Mechanical Design, Instrumentation and Control, Panel Fabrication, Site Construction, Receiver System Operation, and Management from the perspective of the receiver designer/manufacturer. The lessons learned on the receiver system described here consist of two parts: the Problem and one or more identified Solutions. The appendix summarizes an inspection of the advanced receiver panel developed by Boeing that was installed and operated in the Solar Two receiver.

  9. Ceramic high temperature receiver design and tests

    NASA Technical Reports Server (NTRS)

    Davis, S. B.

    1982-01-01

    The High Temperature Solar Thermal Receiver, which was tested a Edwards AFB, CA during the winter of 1980-1981, evolved from technologies developed over a five year period of work. This receiver was tested at the Army Solar Furnace at White Sands, NM in 1976. The receiver, was tested successfully at 1768 deg F and showed thermal efficiencies of 85%. The results were sufficiently promising to lead ERDA to fund our development and test of a 250 kW receiver to measure the efficiency of an open cavity receiver atop a central tower of a heliostat field. This receiver was required to be design scalable to 10, 50, and 100 MW-electric sizes to show applicability to central power tower receivers. That receiver employed rectagular silicon carbide panels and vertical stanchions to achieve scalability. The construction was shown to be fully scalable; and the receiver was operated at temperatures up to 2000 deg F to achieve the performance goals of the experiment during tests at the GIT advanced components test facility during the fall of 1978.

  10. Receivers for the Microwave Radiometer on Juno

    NASA Technical Reports Server (NTRS)

    Maiwald, F.; Russell, D.; Dawson, D.; Hatch, W.; Brown, S.; Oswald, J.; Janssen, M.

    2009-01-01

    Six receivers for the MicroWave Radiometer (MWR) are currently under development at JPL. These receivers cover a frequency range of 0.6 to 22 GHz in approximately octave steps, with 4 % bandwidth. For calibration and diagnosis three noise diodes and a Dicke switch are integrated into each receiver. Each receiver is connected to its own antenna which is mounted with its bore sights perpendicular to the spin axis of the spacecraft. As the spacecraft spins at 2 RPM, the antenna field of view scans Jupiter's atmosphere from limb to nadir to limb, measuring microwave emission down to 1000-bar.

  11. Thermal analysis of honeycomb ceramic air receiver

    NASA Astrophysics Data System (ADS)

    Li, Qing; Wang, Zhifeng; Bai, Fengwu; Chu, Shunzhou; Yang, Bei

    2017-06-01

    This study investigated the heat transfer between air flow and honeycomb ceramic air receiver. A one-dimensional model of the receiver was established considering the distribution of the solar radiation within the channel and the radiative heat transfer between the inner surfaces. The sensitivity studies had been done to explore the influences of the absorber geometric parameters, the incident solar radiation and the air flow rate on the receiver steady-state thermal efficiency and outlet air temperature. The minimal absorber length was analyzed to ensure high thermal efficiency, which is significant for the receiver design and optimization.

  12. Wideband heterodyne receiver for laser communication system

    NASA Technical Reports Server (NTRS)

    Flattau, T.; Lange, R. A.; Mellars, B.; Peyton, J.; Wolczok, J. M. (Inventor)

    1977-01-01

    A heterodyne receiver for laser communication is described which includes a front end having a cooled photomixer contained in a hermetically sealed spaced quality housing designed for wide bandwidth transmission. The photomixer is coupled through a wideband preamplifier to the receiver back end which includes a frequency tracking network and demodulating equipment. The receiver is capable of tracking a Doppler frequency shift of 750 MHz, positive or negative, and has an instantaneous intermediate frequency information bandwidth of 400 MHz. The receiver system is also capable of operating over a wide temperature range and is designed to be suitable for use in outer space communication.

  13. Design and implementation of the CAPS receiver

    NASA Astrophysics Data System (ADS)

    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.

  14. Variable velocity in solar external receivers

    NASA Astrophysics Data System (ADS)

    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. 47 CFR 80.961 - Radiotelephone receiver.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Radiotelephone receiver. 80.961 Section 80.961... MARITIME SERVICES Radiotelephone Installation Required for Vessels on the Great Lakes § 80.961... frequencies. (b) The receiver must have a sensitivity of at least 2 microvolts across 50 ohms for a 20...

  16. Advanced heat receiver conceptual design study

    NASA Technical Reports Server (NTRS)

    Kesseli, James; Saunders, Roger; Batchelder, Gary

    1988-01-01

    Solar Dynamic space power systems are candidate electrical power generating systems for future NASA missions. One of the key components of the solar dynamic power system is the solar receiver/thermal energy storage (TES) subsystem. Receiver development was conducted by NASA in the late 1960's and since then a very limited amount of work has been done in this area. Consequently the state of the art (SOA) receivers designed for the IOC space station are large and massive. The objective of the Advanced Heat Receiver Conceptual Design Study is to conceive and analyze advanced high temperature solar dynamic Brayton and Stirling receivers. The goal is to generate innovative receiver concepts that are half of the mass, smaller, and more efficient than the SOA. It is also necessary that these innovative receivers offer ease of manufacturing, less structural complexity and fewer thermal stress problems. Advanced Brayton and Stirling receiver storage units are proposed and analyzed in this study which can potentially meet these goals.

  17. 21 CFR 1020.10 - Television receivers.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... designed to receive and display a television picture through broadcast, cable, or closed circuit television... parallel to the external surface of the receiver with an area of ten (10) square centimeters and no... from that component or circuit failure which maximizes x-radiation emissions. (4) Critical...

  18. 21 CFR 1020.10 - Television receivers.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... designed to receive and display a television picture through broadcast, cable, or closed circuit television... parallel to the external surface of the receiver with an area of ten (10) square centimeters and no... from that component or circuit failure which maximizes x-radiation emissions. (4) Critical...

  19. 21 CFR 1020.10 - Television receivers.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... designed to receive and display a television picture through broadcast, cable, or closed circuit television... parallel to the external surface of the receiver with an area of ten (10) square centimeters and no... from that component or circuit failure which maximizes x-radiation emissions. (4) Critical...

  20. 21 CFR 1020.10 - Television receivers.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... designed to receive and display a television picture through broadcast, cable, or closed circuit television... parallel to the external surface of the receiver with an area of ten (10) square centimeters and no... from that component or circuit failure which maximizes x-radiation emissions. (4) Critical...

  1. 21 CFR 1020.10 - Television receivers.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... designed to receive and display a television picture through broadcast, cable, or closed circuit television... parallel to the external surface of the receiver with an area of ten (10) square centimeters and no... from that component or circuit failure which maximizes x-radiation emissions. (4) Critical...

  2. 47 CFR 80.858 - Radiotelephone receiver.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... the section must: (1) Have a sensitivity of 50 microvolts; (2) Be capable of operation when energized... showing the name of the receiver manufacturer and the type or model. (d) The sensitivity of a receiver is... of at least 6 decibels. Evidence of a manufacturer's rating or a demonstration of the sensitivity of...

  3. Controlling external factors affecting accounts receivable.

    PubMed

    Ramey, N; Bradley, L

    1991-08-01

    External factors such as complex billing arrangements, decreasing healthcare benefits, and increasing numbers of uninsured workers contribute to a hospital's outstanding accounts receivable. Instituting measures for getting payment in full and as soon as possible can help control for outside influences and reduce outstanding receivables.

  4. Heat-Energy Analysis for Solar Receivers

    NASA Technical Reports Server (NTRS)

    Lansing, F. L.

    1982-01-01

    Heat-energy analysis program (HEAP) solves general heat-transfer problems, with some specific features that are "custom made" for analyzing solar receivers. Can be utilized not only to predict receiver performance under varying solar flux, ambient temperature and local heat-transfer rates but also to detect locations of hotspots and metallurgical difficulties and to predict performance sensitivity of neighboring component parameters.

  5. Cashier/Accounts Receivable Clerk Exploration.

    ERIC Educational Resources Information Center

    Portsmouth City School Board, VA.

    The student materials present exercises designed to simulate the job performed by a cashier/accounts receivable clerk. The content of the course covers job instructions, writing receipts, proving cash, customer accounts, preparing statements, and schedule of accounts receivable. Also included in the document are a pretest and post test for the…

  6. Optimization of MLS receivers for multipath environments

    NASA Technical Reports Server (NTRS)

    Mcalpine, G. A.; Highfill, J. H., III; Irwin, S. H.; Padgett, J. E.

    1975-01-01

    A receiver is designed for aircraft (A/C), which, as a component of the proposed Microwave Landing System (MLS), is capable of optimal performance in the multipath environments found in air terminal areas. Topics discussed include: the angle-tracking problem of the MLS receiver; signal modeling; preliminary approaches to optimal design; suboptimal design; and simulation study.

  7. 47 CFR 32.1170 - Receivables.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 2 2014-10-01 2014-10-01 false Receivables. 32.1170 Section 32.1170 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES UNIFORM SYSTEM OF ACCOUNTS FOR TELECOMMUNICATIONS COMPANIES Instructions for Balance Sheet Accounts § 32.1170 Receivables. (a...

  8. 47 CFR 32.1170 - Receivables.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 2 2013-10-01 2013-10-01 false Receivables. 32.1170 Section 32.1170 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES UNIFORM SYSTEM OF ACCOUNTS FOR TELECOMMUNICATIONS COMPANIES Instructions for Balance Sheet Accounts § 32.1170 Receivables. (a...

  9. 47 CFR 32.1170 - Receivables.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 2 2012-10-01 2012-10-01 false Receivables. 32.1170 Section 32.1170 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES UNIFORM SYSTEM OF ACCOUNTS FOR TELECOMMUNICATIONS COMPANIES Instructions for Balance Sheet Accounts § 32.1170 Receivables. (a...

  10. Liquid cooled fiber thermal radiation receiver

    DOEpatents

    Butler, B.L.

    1985-03-29

    A radiation-to-thermal receiver apparatus for collecting radiation and converting it to thermal energy is disclosed. The invention includes a fibrous mat material which captures radiation striking the receiver. Captured radiation is removed from the fibrous mat material by a transparent fluid within which the material is bathed.

  11. Liquid cooled fiber thermal radiation receiver

    DOEpatents

    Butler, Barry L.

    1987-01-01

    A radiation-to-thermal receiver apparatus for collecting radiation and converting it to thermal energy is disclosed. The invention includes a fibrous mat material which captures radiation striking the receiver. Captured radiation is removed from the fibrous mat material by a transparent fluid within which the material is bathed.

  12. 7 CFR 966.124 - Approved receiver.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... AND ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE TOMATOES GROWN IN FLORIDA Rules and..., as an approved receiver, tomatoes for purposes as set forth in § 966.120(a), shall annually, prior... specified purpose is to occur; (4) Whether or not the receiver packs, repacks or sells fresh tomatoes; (5) A...

  13. 7 CFR 966.124 - Approved receiver.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... AND ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE TOMATOES GROWN IN FLORIDA Rules and..., as an approved receiver, tomatoes for purposes as set forth in § 966.120(a), shall annually, prior... specified purpose is to occur; (4) Whether or not the receiver packs, repacks or sells fresh tomatoes; (5) A...

  14. 7 CFR 966.124 - Approved receiver.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE TOMATOES GROWN IN FLORIDA Rules and..., as an approved receiver, tomatoes for purposes as set forth in § 966.120(a), shall annually, prior... specified purpose is to occur; (4) Whether or not the receiver packs, repacks or sells fresh tomatoes; (5) A...

  15. 7 CFR 966.124 - Approved receiver.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE TOMATOES GROWN IN FLORIDA Rules and..., as an approved receiver, tomatoes for purposes as set forth in § 966.120(a), shall annually, prior... specified purpose is to occur; (4) Whether or not the receiver packs, repacks or sells fresh tomatoes; (5) A...

  16. A planar quasi-optical SIS receiver

    NASA Technical Reports Server (NTRS)

    Stimson, Philip A.; Dengler, Robert J.; Leduc, Henry G.; Cypher, Scott R.; Siegel, Peter H.

    1993-01-01

    A planar, quasi-optical SIS receiver operating at 230 GHz is described. The receiver consists of a 2 x 5 array of half wave dipole antennas with ten niobium-aluminum oxide-niobium SIS junctions on a quartz dielectric-filled parabola. The 1.4 GHz intermediate frequency is coupled from the mixer via coplanar strip transmission lines and 4:1 balun transformers. The receiver is operated at 4.2 K in a liquid helium immersion cryostat. We report accurate measurements of the performance of single receiver elements. A mixer noise temperature of 89 K DSB, receiver noise temperature of 156 K DSB, and conversion loss of 3 dB into a matched load have been obtained.

  17. Avoiding potential problems when selling accounts receivable.

    PubMed

    Ayers, D H; Kincaid, T J

    1996-05-01

    Accounts receivable financing is a potential tool for managing a provider organization's working capital needs. But before entering into a financing agreement, organizations need to consider and take steps to avoid serious problems that can arise from participation in an accounts receivable financing program. For example, the purchaser may cease purchasing the receivables, leaving the organization without funding needed for operations. Or, the financing program may be inordinately complex and unnecessarily costly to the organization. Sometimes the organization itself may fail to comply with the terms of the agreement under which the accounts receivable were sold, thus necessitating that restitution be made to the purchaser or provoking charges of fraud. These potential problems should be addressed as early as possible--before an organization enters into an accounts receivable financing program--in order to minimize time, effort, and expanse and maximize the benefits of the financing agreement.

  18. Directional Receiver for Biomimetic Sonar System

    NASA Astrophysics Data System (ADS)

    Guarato, Francesco; Andrews, Heather; Windmill, James F.; Jackson, Joseph; Gachagan, Anthony

    An ultrasonic localization method for a sonar system equipped with an emitter and two directional receivers and inspired by bat echolocation uses knowledge of the beam pattern of the receivers to estimate target orientation. Rousettus leschenaultii's left ear constitutes the model for the design of the optimal receiver for this sonar system and 3D printing was used to fabricate receiver structures comprising of two truncated cones with an elliptical external perimeter and a parabolic flare rate in the upper part. Measurements show one receiver has a predominant lobe in the same region and with similar attenuation values as the bat ear model. The final sonar system is to be mounted on vehicular and aerial robots which require remote control for motion and sensors for estimation of each robot's location.

  19. High dynamic, low volume GPS receiver

    NASA Technical Reports Server (NTRS)

    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.

  20. EHF low-noise FET receiver

    NASA Technical Reports Server (NTRS)

    Schellenberg, J. M.; Watkins, E. T.

    1983-01-01

    Extremely high frequency (EHF) receivers for military and NASA programs must be small, lightweight, and highly reliable. In connection with recent advances in the development of mm-wave FET devices and circuits, a basis has been obtained for the eventual replacement of diode mixer front-ends by FET preamplifiers in receivers up to 94 GHz. By placing a low noise amplifier in front of the mixer it is possible to achieve a lower system noise figure than that found in conventional mm-wave receivers. A broader bandwidth can also be provided. Attention is given to the receiver configuration, a low noise FET amplifier, an image rejection filter, a dual-gate FET mixer, a FET local oscillator, and a FET receiver.

  1. High dynamic, low volume GPS receiver

    NASA Technical Reports Server (NTRS)

    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.

  2. Giver-receiver asymmetries in gift preferences.

    PubMed

    Teigen, Karl Halvor; Olsen, Marina V G; Solås, Odd Egil

    2005-03-01

    When people are asked to choose between gift items, givers and receivers sometimes show different patterns of preferences. The article reports four experimental studies exploring these giver-receiver asymmetries. Whereas givers tend to prefer exclusive, but smaller gift items, receivers appear to prefer less luxurious, and more useful gifts (Experiment 1). Givers prefer gift vouchers to cash, and are concerned about timing, whereas more receivers accept cash gifts, and claim that it does not matter if the gift arrives late (Experiment 2). One interpretation of the results could be that givers conform more strongly to gift conventions (cultural norms for gift exchange). It is further argued that these differences are not due to a perceived difference between self and others (Experiment 3), but rather because of situational differences. When receivers perform separate evaluations of gifts rather than joint evaluations (pairwise comparisons), they tend to change their preference pattern towards a higher rating of exclusive gift items (Experiment 4).

  3. Enhanced AIS receiver design for satellite reception

    NASA Astrophysics Data System (ADS)

    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).

  4. Temperature influences in receiver clock modelling

    NASA Astrophysics Data System (ADS)

    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.

  5. Terahertz Array Receivers with Integrated Antennas

    NASA Technical Reports Server (NTRS)

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

    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. Terahertz Array Receivers with Integrated Antennas

    NASA Technical Reports Server (NTRS)

    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.

  7. Global Positioning System receiver evaluation results

    SciTech Connect

    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.

  8. High dynamic global positioning system receiver

    NASA Technical Reports Server (NTRS)

    Hurd, W. J. (Inventor)

    1986-01-01

    A Global Positioning System (GPS) receiver having a number of channels, receives an aggregate of pseudorange code time division modulated signals. The aggregate is converted to baseband and then to digital form for separate processing in the separate channels. A fast fourier transform processor computes the signal energy as a function of Doppler frequency for each correlation lag, and a range and frequency estimator computes estimates of pseudorange, and frequency. Raw estimates from all channels are used to estimate receiver position, velocity, clock offset and clock rate offset in a conventional navigation and control unit, and based on the unit that computes smoothed estimates for the next measurement interval.

  9. The Los Alamos beacon receiver array

    SciTech Connect

    Carlos, R.C.; Massey, R.S. )

    1994-07-01

    The authors are interested in studying both the natural background of acoustic and acoustic-gravity waves, for which the sources are not generally known, as well as waves produced by known sources such as large explosions and launches of large rockets. The authors describe radio receivers that monitor transmissions from beacons on geosynchronous satellites. The receivers can detect perturbations of a 300--3,000 s period in the electron density integrated from beacon to receiver, for amplitudes as low as (1--2) [times] 10[sup 13] m[sup [minus]2]. Data are used in studies of atmospheric acoustic and acoustic-gravity waves.

  10. 7 CFR 29.42 - Receiving station.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 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, packing...

  11. A 30 GHz monolithic receive module

    NASA Technical Reports Server (NTRS)

    Mondal, J.; Contolatis, T.; Geddes, J.; Bauhahn, P.; Sokolov, V.

    1990-01-01

    The technical achievements and deliveries made during the duration of the program to develop a 30 GHz monolithic receive module for communication feed array applications and to deliver submodules and 30 GHz monolithic receive modules for experimental evaluation are discussed. Key requirements include an overall receive module noise figure of 5 dB, a 30 dB RF-to-RF gain with six levels of intermediate gain control, a five bit phase shifter, and a maximum power consumption of 250 mW. In addition, the monolithic receive module design addresses a cost goal of less than one thousand dollars (1980 dollars) per module in unit buys of 5,000 or more, and a mechanical configuration that is applicable to a spaceborne phase array system. An additional task for the development and delivery of 32 GHz phase shifter integrated circuit (IC) for deep space communication is also described.

  12. Collector/Receiver Characterization (Fact Sheet)

    SciTech Connect

    Not Available

    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.

  13. Stanley receives 2010 William Gilbert Award: Citation

    NASA Astrophysics Data System (ADS)

    Weiss, Benjamin P.

    2011-06-01

    Sabine Stanley received the William Gilbert Award at the 2010 AGU Fall Meeting, held 13-17 December in San Francisco, Calif. The award recognizes outstanding and unselfish work in magnetism of Earth materials and of the Earth and planets.

  14. Kirschvink receives 2011 William Gilbert Award: Citation

    NASA Astrophysics Data System (ADS)

    Weiss, Benjamin P.

    2012-04-01

    Joseph Kirschvink received the William Gilbert Award at the 2011 AGU Fall Meeting, held 5-9 December in San Francisco, Calif. The award recognizes outstanding and unselfish work in magnetism of Earth materials and of the Earth and planets.

  15. Kirschvink receives 2011 William Gilbert Award: Response

    NASA Astrophysics Data System (ADS)

    Kirschvink, Joseph L.

    2012-04-01

    Joseph Kirschvink received the William Gilbert Award at the 2011 AGU Fall Meeting, held 5-9 December in San Francisco, Calif. The award recognizes outstanding and unselfish work in magnetism of Earth materials and of the Earth and planets.

  16. Lagroix Receives 2008 William Gilbert Award

    NASA Astrophysics Data System (ADS)

    Moskowitz, Bruce M.; Banerjee, Subir K.; Lagroix, France

    2009-04-01

    France Lagroix received the William Gilbert Award at the 2008 AGU Fall Meeting Honors Ceremony, held 17 December in San Francisco, Calif. The award recognizes outstanding and unselfish work in magnetism of Earth materials and of the Earth and planets.

  17. Dennis Kent Receives 2009 William Gilbert Award

    NASA Astrophysics Data System (ADS)

    Tauxe, Lisa; Kent, Dennis

    2010-06-01

    Dennis Kent received the William Gilbert Award at the 2009 AGU Fall Meeting, held 14-18 December in San Francisco, Calif. The award recognizes outstanding and unselfish work in magnetism of Earth materials and of the Earth and planets.

  18. Stanley receives 2010 William Gilbert Award: Response

    NASA Astrophysics Data System (ADS)

    Stanley, Sabine

    2011-06-01

    Sabine Stanley received the William Gilbert Award at the 2010 AGU Fall Meeting, held 13-17 December in San Francisco, Calif. The award recognizes outstanding and unselfish work in magnetism of Earth materials and of the Earth and planets.

  19. Beacon satellite receiver for ionospheric tomography

    NASA Astrophysics Data System (ADS)

    Vierinen, J.; Norberg, J.; Lehtinen, M. S.; Amm, O.; Roininen, L.; Väänänen, A.; Erickson, P. J.; McKay-Bukowski, D.

    2014-12-01

    We introduce a new coherent dual-channel beacon satellite receiver intended for ionospheric tomography. The measurement equation includes neutral atmosphere and ionosphere propagation effects, relative errors in satellite and receiver clocks, and residual Doppler shifts caused by errors in the satellite ephemeris. We also investigate the distribution of errors for phase curve measurements and the use of phase curve measurements for limited angle tomography using the framework of statistical linear inverse problems. We describe the design of our beacon satellite receiver software and present one possible hardware configuration. Finally, we present results obtained using a network of four newly developed receivers and compare the results with those of an existing ionospheric tomography network at Sodankylä Geophysical Observatory.

  20. Digital Signal Processing Based Biotelemetry Receivers

    NASA Technical Reports Server (NTRS)

    Singh, Avtar; Hines, John; Somps, Chris

    1997-01-01

    This is an attempt to develop a biotelemetry receiver using digital signal processing technology and techniques. The receiver developed in this work is based on recovering signals that have been encoded using either Pulse Position Modulation (PPM) or Pulse Code Modulation (PCM) technique. A prototype has been developed using state-of-the-art digital signal processing technology. A Printed Circuit Board (PCB) is being developed based on the technique and technology described here. This board is intended to be used in the UCSF Fetal Monitoring system developed at NASA. The board is capable of handling a variety of PPM and PCM signals encoding signals such as ECG, temperature, and pressure. A signal processing program has also been developed to analyze the received ECG signal to determine heart rate. This system provides a base for using digital signal processing in biotelemetry receivers and other similar applications.

  1. A C-Band satellite receiver

    NASA Astrophysics Data System (ADS)

    Lupinetti, F.; Ingels, F.

    1985-12-01

    The design concept of a 24-channel C-band receiver for satellite TV signals is presented. The system comprises a low-noise amplifier, a 3.7-4.2-GHz/450-910-MHz block down converter, the receiver proper (a modified analog UNF tuner at IF = 45 MHz and a digital channel selector), and an RF modulator providing video and audio on channels 3 or 4. The operation of the receiver is described and illustrated with block diagrams and tables of specifications. A prototype receiver has been found to give good video quality and definition with clear 20-20,000-Hz audio when used with a 4-ft dish antenna.

  2. 47 CFR 80.913 - Radiotelephone receivers.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... public coast stations serving the area in which the vessel is navigated. (d) One or more loudspeakers... at the receiver input to produce an audio output of 50 milliwatts to the loudspeaker with a signal-to...

  3. 47 CFR 80.913 - Radiotelephone receivers.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... public coast stations serving the area in which the vessel is navigated. (d) One or more loudspeakers... at the receiver input to produce an audio output of 50 milliwatts to the loudspeaker with a signal-to...

  4. 47 CFR 80.858 - Radiotelephone receiver.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... frequencies authorized pursuant to § 80.855(a). (b) One or more loudspeakers capable of being used to maintain... receiver input to produce an audio output of 50 milliwatts to the loudspeaker with a signal-to-noise ratio...

  5. 47 CFR 80.858 - Radiotelephone receiver.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... frequencies authorized pursuant to § 80.855(a). (b) One or more loudspeakers capable of being used to maintain... receiver input to produce an audio output of 50 milliwatts to the loudspeaker with a signal-to-noise ratio...

  6. 47 CFR 80.858 - Radiotelephone receiver.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... frequencies authorized pursuant to § 80.855(a). (b) One or more loudspeakers capable of being used to maintain... receiver input to produce an audio output of 50 milliwatts to the loudspeaker with a signal-to-noise ratio...

  7. 47 CFR 80.913 - Radiotelephone receivers.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... public coast stations serving the area in which the vessel is navigated. (d) One or more loudspeakers... at the receiver input to produce an audio output of 50 milliwatts to the loudspeaker with a signal-to...

  8. 47 CFR 80.858 - Radiotelephone receiver.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... frequencies authorized pursuant to § 80.855(a). (b) One or more loudspeakers capable of being used to maintain... receiver input to produce an audio output of 50 milliwatts to the loudspeaker with a signal-to-noise ratio...

  9. 47 CFR 80.913 - Radiotelephone receivers.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... public coast stations serving the area in which the vessel is navigated. (d) One or more loudspeakers... at the receiver input to produce an audio output of 50 milliwatts to the loudspeaker with a signal-to...

  10. NASA Dryden Receives 'New' F-15Ds

    NASA Image and Video Library

    NASA's Dryden Flight Research Center has received three F-15D Eagle aircraft from the U.S. Air Force for flight research and mission support duties. The demilitarized high-performance aircraft were...

  11. Absentee Ballot Track, Receive, and Confirm Act

    THOMAS, 111th Congress

    Rep. Davis, Susan A. [D-CA-53

    2009-05-20

    08/03/2009 Received in the Senate and Read twice and referred to the Committee on Rules and Administration. (All Actions) Tracker: This bill has the status Passed HouseHere are the steps for Status of Legislation:

  12. Go International! Build a Simplified Shortwave Receiver

    ERIC Educational Resources Information Center

    Homoly, Clarke

    2008-01-01

    This article presents a plan for building a shortwave receiver that is doable, educational and has reasonable performance. The project, says the author, can give students years of listening fun without a major financial investment. Potential project improvements are included.

  13. Absentee Ballot Track, Receive, and Confirm Act

    THOMAS, 111th Congress

    Rep. Davis, Susan A. [D-CA-53

    2009-05-20

    08/03/2009 Received in the Senate and Read twice and referred to the Committee on Rules and Administration. (All Actions) Tracker: This bill has the status Passed HouseHere are the steps for Status of Legislation:

  14. Go International! Build a Simplified Shortwave Receiver

    ERIC Educational Resources Information Center

    Homoly, Clarke

    2008-01-01

    This article presents a plan for building a shortwave receiver that is doable, educational and has reasonable performance. The project, says the author, can give students years of listening fun without a major financial investment. Potential project improvements are included.

  15. High dynamic GPS receiver validation demonstration

    NASA Technical Reports Server (NTRS)

    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.

  16. Flexible receiver adapter formal design review

    SciTech Connect

    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.

  17. A handbook for solar central receiver design

    SciTech Connect

    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.

  18. A Multi-Channel Radar Receiver.

    DTIC Science & Technology

    1985-01-07

    Doppler weather radar I ’Multi-channel radar receiver -,, Dual frequency radar , Polarization...V ~ ’.= :• ’> . . S , . . .. - -. .° , . * . - . -. . . A Multi-Channel Radar Receiver 1. INTRODUCTION The 10-cm Doppler weather radar at AFGL is...cm Dual Frequency Doppler Weather Radar . Part I: The Radar System, AFGL-TR-82- 0321 (I). 4. Ussailis, J.S., Leiker, L.A.. Goodman, R.M. IV.

  19. Single-Receiver GPS Phase Bias Resolution

    NASA Technical Reports Server (NTRS)

    Bertiger, William I.; Haines, Bruce J.; Weiss, Jan P.; Harvey, Nathaniel E.

    2010-01-01

    Existing software has been modified to yield the benefits of integer fixed double-differenced GPS-phased ambiguities when processing data from a single GPS receiver with no access to any other GPS receiver data. When the double-differenced combination of phase biases can be fixed reliably, a significant improvement in solution accuracy is obtained. This innovation uses a large global set of GPS receivers (40 to 80 receivers) to solve for the GPS satellite orbits and clocks (along with any other parameters). In this process, integer ambiguities are fixed and information on the ambiguity constraints is saved. For each GPS transmitter/receiver pair, the process saves the arc start and stop times, the wide-lane average value for the arc, the standard deviation of the wide lane, and the dual-frequency phase bias after bias fixing for the arc. The second step of the process uses the orbit and clock information, the bias information from the global solution, and only data from the single receiver to resolve double-differenced phase combinations. It is called "resolved" instead of "fixed" because constraints are introduced into the problem with a finite data weight to better account for possible errors. A receiver in orbit has much shorter continuous passes of data than a receiver fixed to the Earth. The method has parameters to account for this. In particular, differences in drifting wide-lane values must be handled differently. The first step of the process is automated, using two JPL software sets, Longarc and Gipsy-Oasis. The resulting orbit/clock and bias information files are posted on anonymous ftp for use by any licensed Gipsy-Oasis user. The second step is implemented in the Gipsy-Oasis executable, gd2p.pl, which automates the entire process, including fetching the information from anonymous ftp

  20. Flexible receiver accurately tracks multiple threats

    NASA Astrophysics Data System (ADS)

    Browne, Jack

    1988-09-01

    The design and performance of a broadband (0.03-40-GHz) receiver system for electronic-surveillance applications are described. The complete superheterodyne receiver system comprises a control and display unit, a scan display, an equipment frame, and a choice of readily interchangeable RF tuner and demodulator modules with narrow or broad instantaneous bandwidths and BITE capability. Photographs, block diagrams, and tables listing the performance parameters of the modules are provided.

  1. Use of Geodetic Receivers for TAI

    DTIC Science & Technology

    2002-01-01

    corrections. For the computation of TAI, the BIPM then improves the CGGTTS results using the IGS rapid orbits, and replacing the ionospheric corrections...unclassified Standard Form 298 (Rev. 8-98) Prescribed by ANSI Std Z39-18 We recently developed software providing CGGTTS files for geodetic receivers driven... CGGTTS files from RINEX observations files gathered by geodetic receivers such as the Ashtech 2-XII3T into the realization of TAI fits one of the main

  2. Digital time slot display for Omega receiver

    NASA Technical Reports Server (NTRS)

    Smith, R. E.

    1976-01-01

    Methods of decoding a digital word to display alpha-numeric characters for driving a standard seven-segment LED display have been devised for Omega station identification. The circuit could replace the system now being used in Ohio University's Omega receivers, which lights one of eight LED's to signify the Omega time slot being received. The letters A through H, representing the Omega stations, can be read directly from the seven-segment display.

  3. Efficient receiver tuning using differential evolution strategies

    NASA Astrophysics Data System (ADS)

    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.

  4. Adaptive Detector Arrays for Optical Communications Receivers

    NASA Technical Reports Server (NTRS)

    Vilnrotter, V.; Srinivasan, M.

    2000-01-01

    The structure of an optimal adaptive array receiver for ground-based optical communications is described and its performance investigated. Kolmogorov phase screen simulations are used to model the sample functions of the focal-plane signal distribution due to turbulence and to generate realistic spatial distributions of the received optical field. This novel array detector concept reduces interference from background radiation by effectively assigning higher confidence levels at each instant of time to those detector elements that contain significant signal energy and suppressing those that do not. A simpler suboptimum structure that replaces the continuous weighting function of the optimal receiver by a hard decision on the selection of the signal detector elements also is described and evaluated. Approximations and bounds to the error probability are derived and compared with the exact calculations and receiver simulation results. It is shown that, for photon-counting receivers observing Poisson-distributed signals, performance improvements of approximately 5 dB can be obtained over conventional single-detector photon-counting receivers, when operating in high background environments.

  5. 47 CFR 15.121 - Scanning receivers and frequency converters used with scanning receivers.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... converters used with scanning receivers. (a) Except as provided in paragraph (c) of this section, scanning... in paragraph (c) of this section, scanning receivers shall reject any signals from the Cellular.... (c) Scanning receivers and frequency converters designed or marketed for use with scanning...

  6. 47 CFR 15.121 - Scanning receivers and frequency converters used with scanning receivers.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 1 2011-10-01 2011-10-01 false Scanning receivers and frequency converters used with scanning receivers. 15.121 Section 15.121 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Unintentional Radiators § 15.121 Scanning receivers and...

  7. 47 CFR 15.121 - Scanning receivers and frequency converters used with scanning receivers.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 1 2010-10-01 2010-10-01 false Scanning receivers and frequency converters used with scanning receivers. 15.121 Section 15.121 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Unintentional Radiators § 15.121 Scanning receivers and...

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

    ERIC Educational Resources Information Center

    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.…

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

    ERIC Educational Resources Information Center

    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.…

  10. Receiver functions: An exploration seismic perspective

    NASA Astrophysics Data System (ADS)

    van Manen, Dirk-Jan; Curtis, Andrew; Robertsson, Johan

    2015-04-01

    The receiver function technique is arguably the most successful technique in seismology for crustal and upper mantle characterisation. Prompted by the successful application of the receiver function method to multi-component seabed seismic data to derive shear-wave statics, we explore to what extent the receiver function method can be used for general multi-component reflection seismic data processing and vice-versa. We show that the work in the seismological community on moveout correction and stacking of receiver functions can be extended significantly, building on results from the exploration seismic community. We introduce a novel type of space-time domain receiver function, computed by 2D deconvolution, which treats the spatial aspects of mode-conversion completely analogously to the temporal aspects. Thus, the receiver function becomes a two-dimensional transfer function, which shows how far the P-waves have to be shifted in space and delayed in time to match the corresponding PS-converted waves. In addition, series expansions of the traveltime differences lead naturally to two-term moveout approximations and Dix-Krey-type velocity inversion formulae for both the conventional (i.e., time difference as a function of slowness) as well as novel (i.e., time difference as a function of offset) receiver functions. The two approaches, and the required data pre-processing, are illustrated using synthetic multi-component seismic data. We also introduce a model-independent method for reflection receiver function computation, based on stationary phase analysis, which can be used for deconvolution of anelastic and all other propagation effects. This method is inspired by, and closely related to, interferometry and relies on matching the slowness of a particular PP-reflected wave to the slowness of the corresponding PS-converted wave on the source side, and exploiting the fact that the traveltime difference is stationary for the PP- and PS-wave that is reflected and mode

  11. Performance outlook of the SCRAP receiver

    NASA Astrophysics Data System (ADS)

    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

  12. ASTRID© - Advanced Solar Tubular ReceIver Design: A powerful tool for receiver design and optimization

    NASA Astrophysics Data System (ADS)

    Frantz, Cathy; Fritsch, Andreas; Uhlig, Ralf

    2017-06-01

    In solar tower power plants the receiver is one of the critical components. It converts the solar radiation into heat and must withstand high heat flux densities and high daily or even hourly gradients (due to passage of clouds). For this reason, the challenge during receiver design is to find a reasonable compromise between receiver efficiency, reliability, lifetime and cost. There is a strong interaction between the heliostat field, the receiver and the heat transfer fluid. Therefore, a proper receiver design needs to consider these components within the receiver optimization. There are several design and optimization tools for receivers, but most of them focus only on the receiver, ignoring the heliostat field and other parts of the plant. During the last years DLR developed the ASTRIDcode for tubular receiver concept simulation. The code comprises both a high and a low-detail model. The low-detail model utilizes a number of simplifications which allow the user to screen a high number of receiver concepts for optimization purposes. The high-detail model uses a FE model and is able to compute local absorber and salt temperatures with high accuracy. One key strength of the ASTRIDcode is its interface to a ray tracing software which simulates a realistic heat flux distributions on the receiver surface. The results generated by the ASTRIDcode have been validated by CFD simulations and measurement data.

  13. Dish/stirling hybrid-receiver

    DOEpatents

    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.

  14. Liquid cooled, linear focus solar cell receiver

    NASA Astrophysics Data System (ADS)

    Kirpich, A. S.

    1983-12-01

    Separate structures for electrical insulation and thermal conduction which are established within a liquid cooled, linear focus solar cell receiver for use with parabolic or Fresnel optical concentrators are discussed. The receiver includes a V shaped aluminum extrusion with a pair of outer faces each formed with a channel receiving a string of solar cells in thermal contact with the extrusion. Each cell string is attached to a continuous glass cover secured within the channel with spring clips to isolate the string from the external environment. Repair or replacement of solar cells is effected simply by detaching the spring clips to remove the cover/cell assembly without interrupting circulation of coolant fluid through the receiver. The lower surface of the channel in thermal contact with the cells of the string is anodized to establish a suitable standoff voltage capability between the cells and the extrusion. Primary electrical insulation is provided by a dielectric tape disposed between the coolant tube and extrusion. Adjacent solar cells are soldered to interconnect members designed to accommodate thermal expansion and mismatches. The coolant tube is clamped into the extrusion channel with a releasable attachable clamping strip to facilitate easy removal of the receiver from the coolant circuit.

  15. Binomial congestion control at receivers for multicast

    NASA Astrophysics Data System (ADS)

    Zhang, Bing; Liu, Zengji; Xu, Yayan; Li, Zhen; Zhang, Shi

    2004-09-01

    A single rate multicast congestion control for streaming media applications called Binomial congestion control At Receivers for Multicast (BARM) is proposed. Combining aspects of window-based and rate-based congestion control, the protocol shifts most of the congestion control mechanisms to multicast receivers. The main features of BARM are as follows. (1) The protocol adopts binomial algorithm (k=l=0.5, α=0.28, β=0.2 for our implementation) to adjust congestion window, which not only provides TCP-friendliness but decreases abrupt rate fluctuations, making it suitable for real time streaming media multicast applications. (2) The binomial algorithm is executed at the receivers instead of at the sender; to do this, a congestion window is maintained and updated separately by each receiver. Hence the protocol not only has a better scalability but reduces the burden of the sender significantly and is suitable to Client/Server model. (3) The congestion window is converted to the expected receiving rate which is then fed back to the sender if permitted. Compared to window feedback scheme, rate feedback scheme is simpler and increases the scalability. (4) The representative approach is used to suppress the feedback implosion. Simulations results indicate that BARM shows good fairness, TCP-friendliness, smoothness, scalability, and acceptable responsiveness.

  16. Liquid cooled, linear focus solar cell receiver

    DOEpatents

    Kirpich, Aaron S.

    1985-01-01

    Separate structures for electrical insulation and thermal conduction are established within a liquid cooled, linear focus solar cell receiver for use with parabolic or Fresnel optical concentrators. The receiver includes a V-shaped aluminum extrusion having a pair of outer faces each formed with a channel receiving a string of solar cells in thermal contact with the extrusion. Each cell string is attached to a continuous glass cover secured within the channel with spring clips to isolate the string from the external environment. Repair or replacement of solar cells is effected simply by detaching the spring clips to remove the cover/cell assembly without interrupting circulation of coolant fluid through the receiver. The lower surface of the channel in thermal contact with the cells of the string is anodized to establish a suitable standoff voltage capability between the cells and the extrusion. Primary electrical insulation is provided by a dielectric tape disposed between the coolant tube and extrusion. Adjacent solar cells are soldered to interconnect members designed to accommodate thermal expansion and mismatches. The coolant tube is clamped into the extrusion channel with a releasably attachable clamping strip to facilitate easy removal of the receiver from the coolant circuit.

  17. Liquid cooled, linear focus solar cell receiver

    DOEpatents

    Kirpich, A.S.

    1983-12-08

    Separate structures for electrical insulation and thermal conduction are established within a liquid cooled, linear focus solar cell receiver for use with parabolic or Fresnel optical concentrators. The receiver includes a V-shaped aluminum extrusion having a pair of outer faces each formed with a channel receiving a string of solar cells in thermal contact with the extrusion. Each cell string is attached to a continuous glass cover secured within the channel with spring clips to isolate the string from the external environment. Repair or replacement of solar cells is effected simply by detaching the spring clips to remove the cover/cell assembly without interrupting circulation of coolant fluid through the receiver. The lower surface of the channel in thermal contact with the cells of the string is anodized to establish a suitable standoff voltage capability between the cells and the extrusion. Primary electrical insulation is provided by a dielectric tape disposed between the coolant tube and extrusion. Adjacent solar cells are soldered to interconnect members designed to accommodate thermal expansion and mismatches. The coolant tube is clamped into the extrusion channel with a releasably attachable clamping strip to facilitate easy removal of the receiver from the coolant circuit.

  18. Schottky Heterodyne Receivers With Full Waveguide Bandwidth

    NASA Technical Reports Server (NTRS)

    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.

  19. Direct broadcast satellite-radio, receiver development

    NASA Technical Reports Server (NTRS)

    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.

  20. Qualification of TAOS satellite GPS receiver

    NASA Astrophysics Data System (ADS)

    Weninger, Roger M.; Sfeir, Richard; Forgette, Tom T.; Kelton, Phil T.; Najarian, Richard J.

    1992-03-01

    A light-weight, compact GPS receiver developed for a Technology for Autonomous Operational Survivability (TAOS) satellite planned for launch in 1993 is described. The receiver is capable of continuously tracking four primary GPS satellites and sequentially acquiring and tracking other visible satellites with its six channels. Using an eight-state extended Kalman filter it performs pseudo-range and continuous-carrier, delta-range measurements and estimates time-tagged, 3D user position and velocity. Results of qualification testing obtained from a multichannel GPS spaceborne simulation and evaluation system show that with a GPS constellation of 18 satellites and over a period where GDOP is less than 6, the receiver's rms spherical position and per axis velocity errors are less than 14.5 meters and 0.05 m/sec, respectively.

  1. Water intoxication in epileptic patients receiving carbamazepine.

    PubMed Central

    Perucca, E; Garratt, A; Hebdige, S; Richens, A

    1978-01-01

    Plasma sodium and osmolality were determined in 80 adult epileptic patients receiving chronic treatment with carbamazepine and in 50 control patients treated with other anticonvulsant drugs. Mean plasma osmolality was significantly lower in the carbamazepine-treated patients but mean plasma sodium did not differ in the two groups. Hyponatraemia was found in five of the carbamazine-treated patients and hypo-osmolality in six. None of the control patients had hyponatraemia and only one had a borderline low osmolality. Three of the 13 patients receiving carbamazepine alone were hyponatraemic. Plasma sodium concentration correlated negatively with both daily carbamazepine dose and serum carbamazepine level. Free water clearance after an oral water load was determined in six patients on carbamazepine alone and in six normal subjects not receiving drug therapy. The capacity of some of the patients to excrete the water load was found to be grossly impaired. PMID:681958

  2. Air Brayton Solar Receiver, phase 2

    NASA Technical Reports Server (NTRS)

    Deanda, L. E.

    1981-01-01

    An air Brayton solar receiver (ABSR) is discussed. The ABSR consists of a cylindrical, insulated, offset plate fin heat exchanger which is mounted at the focal plane of a fully tracking parabolic solar collector. The receiver transfer heat from the concentrated solar radiation (which impinges on the inside walls of the heat exchanger) to the working fluid i.e., air. The hot air would then e used to drive a small Brayton cycle heat engine. The engine in turn drives a generator which produces electrical energy. Symmetrical and asymmetrical solar power input into the ABSR are analyzed. The symmetrical cases involve the baseline incident flux and the axially shifted incident fluxes. The asymmetrical cases correspond to the solar fluxes that are obtained by reduced solar input from one half of the concentrator or by receiver offset of plus or minus 1 inch from the concentrator optical axis.

  3. Olympus receiver evaluation and phase noise measurements

    NASA Technical Reports Server (NTRS)

    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.

  4. Brayton advanced heat receiver development program

    NASA Technical Reports Server (NTRS)

    Heidenreich, G. R.; Downing, R. S.; Lacey, Dovie E.

    1989-01-01

    NASA Lewis Research Center is managing an advanced solar dynamic (ASD) space power program. The objective of the ASD program is to develop small and lightweight solar dynamic systems which show significant improvement in efficiency and specific mass over the baseline design derived from the Space Station Freedom technology. The advanced heat receiver development program is a phased program to design, fabricate and test elements of a 7-kWe heat-receiver/thermal-energy-storage subsystem. Receivers for both Brayton and Stirling heat engines are being developed under separate contracts. Phase I, described here, is the current eighteen month effort to design and perform critical technology experiments on innovative concepts designed to reduce mass without compromising thermal efficiency and reliability.

  5. High-temperature solar central receivers

    NASA Astrophysics Data System (ADS)

    Skinrood, A. C.

    1981-07-01

    Designs and concepts for solar central receiver thermal power plants are reviewed. Concentrations of over 1,000 suns are now possible, and seven prototype plants, producing from 1-10 MWe, are close to completion, employing cavity and external receiver configurations. Heat transfer fluids are discussed, noting that the water/steam cycle is emerging as the dominant mode; liquid sodium is benefitting from extensive testing for nuclear power plants; molten salt provides thermal storage at $10-30/kWt-hr; high temperature gas systems (815 C) can be applied for gypsum board drying and NH3 production. Heliostats are all of a steel/glass configuration and require mass production to become economical. Thermal storage systems, applications for repowering in conjunction with conventional power plants, and cogeneration for electricity/process heat are examined, and power costs are projected to match those of coal if the central receiver construction costs can be halved.

  6. Enhancements to - and Submillimetre - Integrated Circuit Receivers.

    NASA Astrophysics Data System (ADS)

    Veidt, Bruce George

    1995-01-01

    An important area of radio astronomy instrumentation is the development of sensitive receivers at millimetre - and submillimetre-wavelengths. Over the last decade, there has been steady progress in advancing the technology from using receivers based on mechanically machined waveguides and horn antennas to transmission lines and antennas fabricated using integrated circuit techniques. The motivation has been to simplify the fabrication of the receivers through the use of photolithography and etching. It is hoped that this will eventually lead to the development of focal plane arrays, which have many elements placed side-by-side forming a radio camera. The first part of this thesis addresses one of the problems with the integrated circuit technology, namely the fixed nature of the circuits, by examining one type of electrically-adjustable tuning. In those experiments, the bias voltage was modulated across the active device so as to change its tuning. Unfortunately the tuning effect was severely limited by the electrical nonlinearity of the device. Another part of this thesis builds upon the integrated nature of modern receivers by adding what, up until now, has been an external component: the Josephson effect suppression electromagnet. This technique will allow the receiving elements to be much simpler and smaller than would otherwise be the case. Finally, the last part of this thesis examines another method of constructing antennas and transmission lines using integrated circuit techniques. This work shows the feasibility of integrating a waveguide fabricated with integrated circuit technology with a diagonal horn antenna. This technique will provide another option for receiver designers.

  7. Generalised receiver functions and seismic interferometry

    NASA Astrophysics Data System (ADS)

    Galetti, Erica; Curtis, Andrew

    2012-04-01

    Classical seismological receiver functions are correlational or deconvolutional combinations of vertical and horizontal component seismometer recordings of earthquake waves that focus information on near-receiver subsurface Earth structure and properties. We show that seismic interferometry can be thought of as a generalisation of receiver functions analysis to cases where recordings at pairs of receivers are considered simultaneously, and where either the same or different component recordings are combined. Further, seismic interferometry uses any of deconvolution, convolution and cross-correlation, and energy from either impulsive or random noise sources. We show both how receiver functions can logically be extended to a new, convolutional form, and that the now little-used correlational form of receiver functions contains more intuitive information than previously realised. Seismic interferometry has provided other extraordinary extensions to seismologists' arsenal. Passive noise recordings can be converted into seismograms from virtual (imagined) earthquakes that in turn can be used to image the real Earth. Active sources (e.g., earthquakes or man-made sources) can be redatumed into new, virtual sources elsewhere, or can be converted into virtual sensors (seismometers) that record seismograms from other real earthquakes, man-made sources or noise sources that occur either in the future or in the past. And the ability to construct virtual sources and sensors at desired times and locations (rather than having to wait for earthquake sources that occur at uncontrollable locations) promises more repeatable monitoring of changes in Earth subsurface properties over time. Indeed, so-called coda wave interferometry offers unprecedented accuracy in detecting such changes. Finally, existing theoretical extensions to other regimes such as electromagnetic, electrokinetic and diffusive energy propagation may lead to future revolutions in other domains of science.

  8. The new indicators of accounts receivable excellence.

    PubMed

    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.

  9. Avalanche Photodiode Arrays for Optical Communications Receivers

    NASA Technical Reports Server (NTRS)

    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.

  10. Billing and accounts receivable: fundamentals for improvement.

    PubMed

    Bizon, M M

    1993-07-01

    If a healthcare facility's accounts receivable operation is experiencing problems, the patient accounts manager should survey all areas of his or her responsibility to determine the best method of resolving the difficulties. One effective technique to reduce billing problems is to take a proactive--not reactive--approach. If mistakes can be corrected before they get out of control, and if the patient accounts manager can ensure that claims will not be denied, a healthcare facility's accounts receivable should remain in good condition.

  11. Optical Receiver Based On Luminescent Light Trapping

    NASA Technical Reports Server (NTRS)

    Perry, Joseph W.; Cole, Terry; Zewail, Ahmed H.

    1991-01-01

    Experiment demonstrates feasibility of optical-communication receiver based on luminescent light trapping. Light-gathering element plate of transparent material impregnated with laser dye. Light from distant laser transmitter falls on plate and absorbed by dye molecules, which become excited and reradiate. Reradiated light confined within plate by total internal reflection as it propagates toward edge of plate. Light arriving at edge escapes from plate and detected by small, high-speed, high-gain photomultiplier tubes or other photosensitive devices. Simple, inexpensive, and accepts light from almost any angle. Receiver of this configuration supports reception of data at rate of 13 MHz and higher.

  12. Downhole receiver function: A case study

    USGS Publications Warehouse

    Mehta, K.; Snieder, R.; Graizer, V.

    2007-01-01

    Receiver function is defined as the spectral ratio of the radial component and the vertical component of the ground motion. It is used to characterize converted waves. We extend the use of the receiver function to downhole data using waves recorded in a borehole, excited by an earthquake of magnitude 4.0 near San Francisco, California, on 26 June 1994. The focal depth of the event was 6.6 km and the epicenter was located at a distance of 12.6 km from the borehole array. Six three-component sensors were located at different depths in a borehole. To extract a coherent response of the near-surface from the incoherent earthquake waves, we deconvolve the waves recorded by the sensors at different depths with the waves recorded by the sensor on the surface. Deconvolution applied to the waves in the S-time window recorded by the radial component result in an upgoing and a downgoing wave propagating with S-wave velocity. For the waves in the P-time window recorded by the radial component, deconvolution also gives an upgoing and a down-going wave propagating with S-wave velocity. This interesting result suggests a P-to-S conversion at a depth below the deepest sensor. To diagnose this we compute the receiver function for the borehole recording of the earthquake waves. The receiver function shows an upgoing wave with an arrival close to time t = 0 for the deepest sensor. The agreement of the upgoing wave in the receiver function with the travel-time curve for the P-to-S converted wave, calculated using the P- and the S-wave velocity profile, supports the hypothesis of a pronounced P-to-S conversion. We present a synthetic example to illustrate that the first arrival of the receiver function applied to borehole data gives the upward-propagating P-to-S converted wave. To corroborate the observation of the mode conversion, we apply receiver function to a different earthquake data recorded by the same borehole array in 1998. The focal depth of the event was 6.9 km and the

  13. Turbulent flow inside a solar concentrator receiver

    NASA Astrophysics Data System (ADS)

    Ramirez, Manuel; Ramos, Eduardo

    2014-11-01

    A solar concentrator receiver is a heat exchanger designed to absorb a beam of radiant heat coming from a field of heliostats. Inside the device, a slow forced flow generated bye an external pressure gradient is present, together with a natural convective a turbulent flow produced by the large temperature gradients due to intense heating. We present a model of this device based on the numerical solution of the mass, momentum and energy conservation equations. We consider heating conditions that lead to turbulence convective flow. For this season, a large eddy simulation model is incorporated. The results are potentially useful for the design of solar concentrator receivers.

  14. Optical and thermal performance of bladed receivers

    NASA Astrophysics Data System (ADS)

    Pye, John; Coventry, Joe; Ho, Clifford; Yellowhair, Julius; Nock, Ian; Wang, Ye; Abbasi, Ehsan; Christian, Joshua; Ortega, Jesus; Hughes, Graham

    2017-06-01

    Bladed receivers use conventional receiver tube-banks rearranged into bladed/finned structures, and offer better light trapping, reduced radiative and convective losses, and reduced tube mass, based on the presented optical and thermal analysis. Optimising for optical performance, deep blades emerge. Considering thermal losses leads to shallower blades. Horizontal blades perform better, in both windy and no-wind conditions, than vertical blades, at the scales considered so far. Air curtains offer options to further reduce convective losses; high flux on blade-tips is still a concern.

  15. Optimization of MLS receivers for multipath environments

    NASA Technical Reports Server (NTRS)

    Mcalpine, G. A.; Highfill, J. H., III

    1976-01-01

    The design of a microwave landing system (MLS) aircraft receiver, capable of optimal performance in multipath environments found in air terminal areas, is reported. Special attention was given to the angle tracking problem of the receiver and includes tracking system design considerations, study and application of locally optimum estimation involving multipath adaptive reception and then envelope processing, and microcomputer system design. Results show processing is competitive in this application with i-f signal processing performance-wise and is much more simple and cheaper. A summary of the signal model is given.

  16. A functional description of the advanced receiver

    NASA Technical Reports Server (NTRS)

    Hinedi, S.

    1990-01-01

    The breadboard Advanced Receiver 2 (ARX 2) that is currently being built for future use in NASA's Deep Space Network (DSN) is described. The hybrid analog/digital receiver performs multiple functions including carrier, subcarrier, and symbol synchronization. Tracking can be achieved for residual, suppressed, or hybrid carriers and for both sinusoidal and square-wave subcarriers. Other functions such as time-tagged Doppler extraction and monitor/control are also discussed, including acquisition algorithms and lock-detection schemes. System requirements are specified and a functional description of the ARX 2 is presented. The various digital signal-processing algorithms used are also discussed and illustrated with block diagrams.

  17. Suppression of Interchannel Interference in FM Receivers

    DTIC Science & Technology

    1979-07-01

    comprehensive receiver with no unknown inputs. Recalling that in the case of FM, the modulation functions are MI(t) = kI(t) and m 2 (t) = k2 (t) and...r) -- = a.2 [ain(4i1 - cp2) + r sin( I 2 - ) - sin(cp1 - ) h ’r)(10 wher e and t2 denote the phase modulation of the stronger and weaker received FM...reveals a typical result for a first order PLL design with a single CW interferer located at the center of the IF frequency band, i. e., no

  18. Mini-L Loran-C receiver

    NASA Technical Reports Server (NTRS)

    Burhans, R. W.

    1977-01-01

    A brief description of the Loran-C system is presented with a suggested receiver based on a standard AM-FM integrated circuit chip. Construction details of the Mini-L Loran-C prototype front-end are considered. The Mini-L system was bench tested for approximately 500 hours under a variety of reception conditions. The Mini-L concept combined with a microprocessor system is a promising approach to the development of truly low-cost Loran-C receivers for the marine and airborne user.

  19. Probability of Intercept in Electronic Countermeasures Receivers

    DTIC Science & Technology

    1975-12-01

    modulating signals A and B are input to the 𔃻WT helix caus.ing a single frequency on the helix of TWT #1 to produce phase modu- lation of frequency A...and harmonics of A in TWT #1. A single frequency on the helix of TVT 42 produces phase modulation of frequency B and harmonics of B in TWT #2. The high...with YIG Pres’Žlector 34 9 Superheterodyne Receiver YIG z iter TWT 36 10 Wideband crystal video receiver 38 11 Tangential Sensitivity 40 12 Sensitivity

  20. Building and Testing a Portable VLF Receiver

    NASA Technical Reports Server (NTRS)

    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.

  1. 17 CFR 256.143 - Accounts receivable.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... SYSTEM OF ACCOUNTS FOR MUTUAL SERVICE COMPANIES AND SUBSIDIARY SERVICE COMPANIES, PUBLIC UTILITY HOLDING COMPANY ACT OF 1935 3. Current and Accrued Assets § 256.143 Accounts receivable. This account shall include amounts due on open accounts, other than amounts due from associate companies. ...

  2. 17 CFR 256.143 - Accounts receivable.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... SYSTEM OF ACCOUNTS FOR MUTUAL SERVICE COMPANIES AND SUBSIDIARY SERVICE COMPANIES, PUBLIC UTILITY HOLDING COMPANY ACT OF 1935 3. Current and Accrued Assets § 256.143 Accounts receivable. This account shall include amounts due on open accounts, other than amounts due from associate companies. ...

  3. 17 CFR 256.141 - Notes receivable.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... SYSTEM OF ACCOUNTS FOR MUTUAL SERVICE COMPANIES AND SUBSIDIARY SERVICE COMPANIES, PUBLIC UTILITY HOLDING COMPANY ACT OF 1935 3. Current and Accrued Assets § 256.141 Notes receivable. This account shall include... other than associate companies. The account shall be so maintained as to show separately amounts due...

  4. 17 CFR 256.141 - Notes receivable.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... SYSTEM OF ACCOUNTS FOR MUTUAL SERVICE COMPANIES AND SUBSIDIARY SERVICE COMPANIES, PUBLIC UTILITY HOLDING COMPANY ACT OF 1935 3. Current and Accrued Assets § 256.141 Notes receivable. This account shall include... other than associate companies. The account shall be so maintained as to show separately amounts due...

  5. A 20 GHz Active Receive Slot Array

    NASA Technical Reports Server (NTRS)

    Tulintseff, A. N.; Lee, K.; Sukamto, L.; Chew, W.

    1994-01-01

    A 20 GHz active receive slot array has been developed for operation in the downlink frequency band of NASA's Advanced Communication Technology Satellite (ACTS) for the ACTS Mobile Terminal (AMT) project. The AMT is to demonstrate voice and data communication between a mobile terminal in Los Angeles, California, and a fixed terminal in Cleveland, Ohio, via the ACTS satellite.

  6. Global lithospheric imaging using teleseismic receiver functions

    NASA Astrophysics Data System (ADS)

    Rondenay, S.; Spieker, K.; Halpaap, F.; Farestveit, M.; Sawade, L.; Zijerveld, L.

    2015-12-01

    Project GLImER (Global Lithospheric Imagining using Earthquake Recordings) aims to conduct a global survey of lithospheric interfaces using converted teleseismic body waves. Data from permanent and temporary seismic networks worldwide will be processed automatically to produce global maps of key interfaces (Moho, intra-lithospheric interfaces, lithosphere-asthenosphere boundary). In this presentation, we discuss the challenges associated with automating the analysis of converted waves and the potential of the resulting data products to be used in novel imaging approaches. With regards to automation, we address in particular the search for an optimal deconvolution method in receiver function analysis. To do so, we carry out a systematic comparison of various commonly used deconvolution methods and find that all methods produce equally robust receiver functions provided that a suitable regularization parameter is found. We further note that a suitable regularization can be found objectively for most approaches, thus challenging the belief that only time-domain deconvolution is a viable option for receiver function automation. With regards to imaging applications, we investigate how the resulting global database of receiver functions will be amenable to existing processing approaches as well as new approaches adapted from seismic exploration, including industry-based interpretation tools.

  7. USEPA CSO CAPSTONE REPORT: RECEIVING WATER IMPACTS

    EPA Science Inventory

    Urban storm-generated combined sewer overflows (CSOs) significantly contribute to the degradation of the nation's water quality. Although not one of the largest pollution sources by volume, their impacts on receiving waters can be locally intense and visible due to shock effect a...

  8. 7 CFR 29.42 - Receiving station.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 2 2014-01-01 2014-01-01 false Receiving station. 29.42 Section 29.42 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE COMMODITY STANDARDS AND STANDARD CONTAINER REGULATIONS...

  9. Workshop summary: Receivers for laser power beaming

    NASA Technical Reports Server (NTRS)

    Landis, Geoffrey A.

    1993-01-01

    At the Space Photovoltaics Research and Technology (SPRAT) conference at NASA Lewis Research Center, a workshop session was held to discuss issues involved in using photovoltaic arrays ('solar cells') to convert laser power into electrical power for use as receiving elements for beamed power.

  10. Reasons Parents Exempt Children from Receiving Immunizations

    ERIC Educational Resources Information Center

    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…

  11. Some Books about Alaska Received in 1987.

    ERIC Educational Resources Information Center

    Alaska State Dept. of Education, Juneau. Div. of State Libraries.

    This is the 1987 edition of an annual annotated listing of Alaska-Arctic related publications received by the Alaska Division of State Libraries. Divided into four sections, this bibliography describes each book, identifies the publisher and price per copy, and includes ISBN numbers. Some of the entries also include the Library of Congress numbers…

  12. 47 CFR 80.913 - Radiotelephone receivers.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... radiotelephone installation must have a sensitivity of at least 50 microvolts in the case of MF equipment, and 1... be capable of efficient operation when energized by the reserve source of energy. (g) The sensitivity... sensitivity of a required receiver computed on this basis must be furnished upon request of the Commission. ...

  13. 7 CFR 966.124 - Approved receiver.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Approved receiver. 966.124 Section 966.124 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements..., or its duly authorized agents, shall give prompt consideration to each application for an approved...

  14. Foliation Mapping at Depth Using Receiver Functions

    NASA Astrophysics Data System (ADS)

    Mahan, K. H.; Schulte-Pelkum, V.

    2013-12-01

    Seismic azimuthal and radial anisotropy are often treated separately for convenience and computational simplicity. When tilted symmetry axis anisotropy is present, nonlinear coupling effects lead to strong Love-to-Rayleigh scattering in surface waves and high-amplitude azimuthally dependent conversions in P-to-SV and P-to-SH converted body waves. The majority of receiver function studies that use waveform modeling thus infer steeply tilted symmetry axes of anisotropy - not because those are more common than horizontal symmetry axes in the lithosphere, but because of their much higher signal amplitudes compared to the horizontal symmetry axis case. Receiver function waveform modeling is subject to many tradeoffs; the signal amplitude depends on the tilt angle, strength of anisotropy, isotropic velocity contrast, and details of the elastic tensor symmetry (such as slow or fast symmetry axis, shape factor, etc.). We present an alternative approach that reduces the information in the waveforms to two parameters, namely the strike and depth of anisotropic and dipping structures. The method is based on finding polarity reversals in converted phases and makes use of a systematic relationship in back-azimuth between radial and tangential component receiver functions. It is insensitive to the tradeoffs mentioned above. We show that the technique reduces complex azimuthally dependent receiver functions to simple parameters that can be interpreted in a geological context. We present examples from Taiwan, the Himalaya, and the western US.

  15. Kopp Receives 2012 William Gilbert Award: Citation

    NASA Astrophysics Data System (ADS)

    Kirschvink, Joseph L.

    2013-10-01

    Robert E. Kopp received the 2012 William Gilbert Award at the 2012 AGU Fall Meeting, held 3-7 December in San Francisco, Calif. The award recognizes outstanding and unselfish work in magnetism of Earth materials and of the Earth and planets.

  16. Fung receives 2004 Roger Revelle Medal

    NASA Astrophysics Data System (ADS)

    Holland, Elisabeth A.; Doney, Scott A.; Fung, Inez

    Inez Fung received the Revelle Medal at the 2004 Fall Meeting Honors Ceremony on 15 December, in San Francisco, California. The medal is given for outstanding contributions in atmospheric sciences, atmosphere-ocean coupling, atmosphere-land coupling, biogeochemical cycles, climate, or related aspects of the Earth system.

  17. Using Unmanned Aerial Vehicles and GPS Receivers

    NASA Technical Reports Server (NTRS)

    Gary, B.

    1995-01-01

    It is proposed that a small fleet of unmanned aerial vehicles (UAVs) be used over a period of years to monitor the rise of pressure surfaces caused by the hypothesized rise in average temperature of the troposphere due to global warming. Global Positioning Satellite System (GPS) receivers would be used for the precise tracking required.

  18. Fatigue in patients receiving palliative care.

    PubMed

    Ream, Emma

    This article discusses fatigue in patients receiving palliative care. The article initially considers the prevalence of fatigue in different groups of palliative care patients, then addresses how it manifests before reviewing how it can be assessed and managed. The focus of the article is on palliative care but it draws on, and has relevance for, chronic disease more widely.

  19. Selling accounts receivable can improve cash flow.

    PubMed

    Spiegel, M

    1989-09-01

    New financing programs especially geared to accounts receivable allow healthcare organizations to convert these assets into cash literally overnight and at costs below the prime interest rate. Certain pooled versions of the financing strategy include non-recourse features that guard against sharing bad debts among the participants. These pooled programs generally allow hospitals to continue managing and billing their own accounts.

  20. Signal Reception via Multi-Platform Receivers

    DTIC Science & Technology

    2012-09-01

    interference cancellation, multi-platform receivers, signal collection, signal interception 15. NUMBER OF PAGES 71 16. PRICE CODE 17. SECURITY ...CLASSIFICATION OF REPORT Unclassified 18. SECURITY CLASSIFICATION OF THIS PAGE Unclassified 19. SECURITY CLASSIFICATION OF ABSTRACT Unclassified...Quadrature Phase Shift Keying SIC Successive Interference Cancellation SNR Signal-To-Noise Ratio SOI Signal Of Interest WLAN Wireless Local Area

  1. Some Books about Alaska Received in 1990.

    ERIC Educational Resources Information Center

    Alaska State Dept. of Education, Juneau. Div. of State Libraries.

    This annual bibliography of Alaska- and Arctic-related publications received by the Alaska Division of State Libraries is divided into three categories. There are 26 titles in the "Juvenile Fiction" section, 122 in the "Adult Non-Fiction" section, and 19 in the "Adult Fiction" section. Government publications are…

  2. 47 CFR 32.1170 - Receivables.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ..., matured rents, and interest receivable under monthly settlements on short-term loans, advances, and open... shall be included in Account 1410, Other noncurrent assets, as a reduction of the carrying value of the..., Other noncurrent assets. (h) Subsidiary record categories shall be maintained in order that the...

  3. 47 CFR 32.1170 - Receivables.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ..., matured rents, and interest receivable under monthly settlements on short-term loans, advances, and open... shall be included in Account 1410, Other noncurrent assets, as a reduction of the carrying value of the..., Other noncurrent assets. (h) Subsidiary record categories shall be maintained in order that the...

  4. Why Receiving Feedback Collides with Self Determination

    ERIC Educational Resources Information Center

    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…

  5. PiVoT GPS Receiver

    NASA Technical Reports Server (NTRS)

    Wennersten, Miriam Dvorak; Banes, Anthony Vince; Boegner, Gregory J.; Dougherty, Lamar; Edwards, Bernard L.; Roman, Joseph; Bauer, Frank H. (Technical Monitor)

    2001-01-01

    NASA Goddard Space Flight Center has built an open architecture, 24 channel space flight GPS receiver. The CompactPCI PiVoT GPS receiver card is based on the Mitel/GEC Plessey Builder-2 board. PiVoT uses two Plessey 2021 correlators to allow tracking of up to 24 separate GPS SV's on unique channels. Its four front ends can support four independent antennas, making it a useful card for hosting GPS attitude determination algorithms. It has been built using space quality, radiation tolerant parts. The PiVoT card will track a weaker signal than the original Builder 2 board. It also hosts an improved clock oscillator. The PiVoT software is based on the original Plessey Builder 2 software ported to the Linux operating system. The software is POSIX complaint and can easily be converted to other POSIX operating systems. The software is open source to anyone with a licensing agreement with Plessey. Additional tasks can be added to the software to support GPS science experiments or attitude determination algorithms. The next generation PiVoT receiver will be a single radiation hardened CompactPCI card containing the microprocessor and the GPS receiver optimized for use above the GPS constellation. PiVoT was flown successfully on a balloon in July, 2001, for its first non-simulated flight.

  6. Reasons Parents Exempt Children from Receiving Immunizations

    ERIC Educational Resources Information Center

    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…

  7. A 20 GHz Active Receive Slot Array

    NASA Technical Reports Server (NTRS)

    Tulintseff, A. N.; Lee, K.; Sukamto, L.; Chew, W.

    1994-01-01

    A 20 GHz active receive slot array has been developed for operation in the downlink frequency band of NASA's Advanced Communication Technology Satellite (ACTS) for the ACTS Mobile Terminal (AMT) project. The AMT is to demonstrate voice and data communication between a mobile terminal in Los Angeles, California, and a fixed terminal in Cleveland, Ohio, via the ACTS satellite.

  8. Guidelines for Receiving State Capital Outlay Funds.

    ERIC Educational Resources Information Center

    Georgia State Dept. of Education, Atlanta. Facilities Services Unit.

    This document presents Georgia's guidelines for receiving state capital outlay funds. The procedure is divided into three parts: preliminary planning, design and preconstruction, and construction. The guide describes how the preliminary planning phase utilizes the state's schedule of events for project administration and provides explicit…

  9. 7 CFR 29.42 - Receiving station.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 2 2011-01-01 2011-01-01 false Receiving station. 29.42 Section 29.42 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE COMMODITY STANDARDS AND STANDARD CONTAINER REGULATIONS TOBACCO...

  10. Omega time transmissions and receiving requirements

    NASA Technical Reports Server (NTRS)

    Chi, A. R.; Fletcher, L. A.; Casselman, C. J.

    1971-01-01

    A short history is given of the development of dual VLF time transmission techniques. The theory of time recovery from the relative phase of the dual frequency transmission is presented. The transmission and receiving requirements for cycle identification and cycle ambiguity resolution are described. Finally, an experiment to test the capability of time transmission of the OMEGA system is proposed

  11. Compact multichannel imaging laser radar receiver

    NASA Astrophysics Data System (ADS)

    Burns, Hoyt N.; Yun, Steven T.; Keltos, Michael L.; Kimmet, James S.

    1999-05-01

    Direct detection imaging Laser Radar (LADAR) produces 3-dimensional range imagery that can be processed to provide target acquisition and precision aimpoint definition in real time. This paper describes the current status of the Parallel Multichannel Imaging LADAR Receiver (PMR), developed under an SBIR Phase II program by the Air Force Research Laboratory, Munitions Directorate (AFRL/MN). The heart of the PMR is the Multichannel Optical Receiver Photonic Hybrid (MORPH), a high performance 16-channel LADAR receiver card which includes fiber-coupled detectors, pulse discrimination, and range counting circuitry on a 3 X 5 inch circuit card. The MORPH provides high downrange resolution (3 inches), multiple-hit (8 per channel) range and reflectance data for each detector. Silicon (Si) and indium gallium arsenide (InGaAs) pin diode or avalanche photodiode (APD) detectors are supported. The modular PMR uses an array of MORPH circuit cards to form a compact multichannel imaging LADAR receiver with any multiple of 16 channels. A 32-channel system measures 3 X 5 X 1.4 inches and weighs 1 lb. A prototype PMR system is currently undergoing field-testing. This paper focuses on field test results and applications of the PMR technology.

  12. Using Unmanned Aerial Vehicles and GPS Receivers

    NASA Technical Reports Server (NTRS)

    Gary, B.

    1995-01-01

    It is proposed that a small fleet of unmanned aerial vehicles (UAVs) be used over a period of years to monitor the rise of pressure surfaces caused by the hypothesized rise in average temperature of the troposphere due to global warming. Global Positioning Satellite System (GPS) receivers would be used for the precise tracking required.

  13. Woodhouse receives 2001 Inge Lehmann Award

    NASA Astrophysics Data System (ADS)

    Dziewonski, Adam M.; Woodhouse, John

    John Woodhouse received the Inge Lehmann Award at the 2001 Fall Meeting Honors Ceremony on 12 December, in San Francisco, California. The award is given for outstanding contributions to the understanding of the structure, composition, and dynamics of the Earth's mantle and core.

  14. Solar-central-receiver fuels and chemicals

    NASA Astrophysics Data System (ADS)

    Carling, R. W.; Fish, J. D.; Radosevich, L. G.; Vitko, J., Jr.

    1981-08-01

    Solar central receiver fuels and chemicals processes were studied. Ethane pyrolysis and steam reforming of methane were investigated in-depth in addition to coal gasification, oil shale retorting, and biomass flash pyrolysis. The study criteria, status of ongoing work, and future activities are described.

  15. Postsecondary Student Perceptions of Received Mathematical Proofs

    ERIC Educational Resources Information Center

    Wiest, John

    2015-01-01

    This article reports on a study investigating how postsecondary students interact with mathematical proofs with a focus on how they go about unpacking a "received proof," how they make meaning from what they are given, and whether they believe that mathematical meaning can be drawn from such proofs. Case studies were conducted with seven…

  16. Contemporary criticisms of the received wilderness idea

    Treesearch

    J. Baird Callicott

    2000-01-01

    Names are important. The name “wilderness” is fraught with historical baggage obfuscating the most important role of wilderness areas for contemporary conservation. The received wilderness idea has been and remains a tool of androcentrism, racism, colonialism, and genocide. It privileges virile and primitive recreation, because the...

  17. The hidden costs of accounts receivable.

    PubMed

    McCormick, E J

    1993-11-01

    To maintain and expand their missions, hospitals must make the best use of their assets. Knowing the true cost of accounts receivable is important for efficient operations. Knowing how to reduce this cost is critical for liquidity. This article offers a guide to ensuring these assets are used most productively.

  18. Hybrid receiver conceptual design and test report

    NASA Technical Reports Server (NTRS)

    Klare, S. W.; Crawford, J. J.

    1978-01-01

    The Hybrid Receiver described uses an acquisition and demodulation scheme tailored to the Jovian environment. The large Doppler offsets expected during initial acquisition led to development of the Hilbert Acquisition Aid, which provides for rapid acquisition for low signal to noise densities.

  19. Interpreting spatially stacked Sp receiver functions

    NASA Astrophysics Data System (ADS)

    Lekić, Vedran; Fischer, Karen M.

    2017-08-01

    Conversions of shear waves (S) to compressional waves (P), often analysed as Sp receiver functions, are useful for studying upper-mantle layering, and have been used to map upper-mantle seismic impedance interfaces in various tectonic settings. Recently, common conversion point (CCP) stacking of Sp receiver functions has revealed variations of lithospheric thickness across short horizontal distances. However, compared to Ps receiver functions and reflection, only limited work has been done towards quantifying the interpretability of Sp receiver functions, especially in settings where large lateral structure variations are present. Using the spectral element method, we model wave propagation and S-to-P conversion through simple synthetic models with varying velocity interface topography. We systematically explore the effects of wave frequency content, seismometer spacing and illumination geometry on CCP stacked Sp receiver functions in settings where velocity interface depth varies laterally. We observe that the resolving power of Sp receiver functions decreases with decreasing frequency content, and that upward deflections of velocity interfaces are more difficult to observe than are downward deflections, an asymmetry that primarily arises due to corner diffractions. Furthermore, we document how the relationship between the angle of illumination and the orientation of the topography of the velocity interfaces largely determines the apparent interface slope and strongly affects the amplitude of Sp phases in the CCP stacks. Indeed, under certain illumination geometries, strong velocity contrasts across a dipping lithosphere-asthenosphere boundary may not produce detectable Sp phases at the surface. Furthermore, diffractions arising from corners of interface topography can produce artefacts in CCP stacks that masquerade as mid-lithospheric impedance jumps or drops, as well as gently sloped sublithospheric impedance drops. We find that estimates based on Fresnel zone

  20. [Are domiciliary care patients receiving adequate thromboprophylaxis?].

    PubMed

    Cátedra, B; Muñoz, F; Cabello, L

    2014-01-01

    The study aims to determine the percentage of patients treated at home with an indication of prophylaxis of thromboembolic disease (TED) according to the PRETEMED guidelines and whether they receive such prophylaxis. A cross-sectional descriptive study was conducted in Segovia Palace Health Centre (Madrid). to be included in the domiciliary care protocol. terminal patient, hospitalised or surgery in the last 3 months. The variables used include, age, sex, duration of domiciliary care, mobility, anticoagulant or antiplatelet treatment and reason, and associated and precipitating factors to calculate the risk of TED according to the PRETEMED guidelines, and if they receive such prophylaxis, by reviewing computerised medical records and meeting with the staff responsible. The study included a total of 187 patients, of whom 81% were women There was a significant differences in mean age by sex (men, 76.91 years, 95% CI; 72.59-81.24, and women, 86.72 years, 95% CI; 72.59-81.24, P<.05). Almost two-thirds (65%) walked in the home. There were 3.7% patients who had an indication for receiving prophylaxis, but did not receive it, although 85.8% of them were on anticoagulants or antiplatelet therapy for other reasons. Most patients in domiciliary care have a low baseline risk of developing a TED episode in our study. There should be more emphasis placed on the prophylaxis of TED in acute medical episodes in which patients with slightly elevated risk may increase the likelihood of TED. Observational studies should be conducted to study the baseline risk and the subsequent development of TED in the population receiving home care. Copyright © 2012 Sociedad Española de Médicos de Atención Primaria (SEMERGEN). Publicado por Elsevier España. All rights reserved.

  1. Vulcan: A deep-towed CSEM receiver

    NASA Astrophysics Data System (ADS)

    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.

  2. The 30-GHz monolithic receive module

    NASA Technical Reports Server (NTRS)

    Bauhahn, P.; Geddes, J.; Sokolov, V.; Contolatis, T.

    1988-01-01

    The fourth year progress is described on a program to develop a 27.5 to 30 GHz GaAs monolithic receive module for spaceborne-communication antenna feed array applications, and to deliver submodules for experimental evaluation. Program goals include an overall receive module noise figure of 5 dB, a 30 dB RF to IF gain with six levels of intermediate gain control, a five bit phase shifter, and a maximum power consumption of 250 mW. Submicron gate length single and dual gate FETs are described and applied in the development of monolithic gain control amplifiers and low noise amplifiers. A two-stage monolithic gain control amplifier based on ion implanted dual gate MESFETs was designed and fabricated. The gain control amplifier has a gain of 12 dB at 29 GHz with a gain control range of over 13 dB. A two-stage monolithic low noise amplifier based on ion implanted MESFETs which provides 7 dB gain with 6.2 dB noise figure at 29 GHz was also developed. An interconnected receive module containing LNA, gain control, and phase shifter submodules was built using the LNA and gain control ICs as well as a monolithic phase shifter developed previously under this program. The design, fabrication, and evaluation of this interconnected receiver is presented. Progress in the development of an RF/IF submodule containing a unique ion implanted diode mixer diode and a broadband balanced mixer monolithic IC with on-chip IF amplifier and the initial design of circuits for the RF portion of a two submodule receiver are also discussed.

  3. Safety of daptomycin in patients receiving hemodialysis.

    PubMed

    Mueller, Bruce A; Crompton, Jason A; Donovan, Brian J; Yankalev, Sara; Lamp, Kenneth C

    2011-07-01

    To determine the safety of daptomycin administered using a variety of doses and dosing frequencies in patients receiving intermittent hemodialysis who had probable or confirmed gram-positive infections. Analysis of data from the Cubicin Outcomes Registry and Experience (CORE), a multicenter, retrospective, observational registry. Fifty-four study sites, mostly (46%) large teaching hospitals. Three hundred ninety-three adults in the CORE registry who received intermittent hemodialysis between 2005 and 2008. The CORE registry is noninterventional and collects standard-of-care data on daptomycin treatment from health care institutions. Of the 393 patients, 370 (94%) could be categorized by daptomycin dosing frequency: every 48 hours (251 patients [64%]), 3 times/week (87 [22%]), and every 24 hours (32 [8%]); the remaining 23 (6%) had unreported dosing frequencies or received a single dose of daptomycin. Three hundred eighty-four patients (98%) received part of their daptomycin therapy as an inpatient and 129 patients (33%) received part of their daptomycin therapy in an intensive care setting. The primary infection type was bacteremia (224 patients [57%]), and the most common pathogen was Staphylococcus aureus (155 patients [39%]). Thirty-eight adverse events possibly related to daptomycin occurred in 28 patients (7%); increased blood creatine kinase level (7 patients [1.8%]) was the most common adverse event. Adverse-event rates were similar across all dosing regimens. In these patients undergoing hemodialysis, daptomycin was a well-tolerated treatment for gram-positive infections across several doses and dosing frequencies. Further study in prospective trials is warranted.

  4. A GPS Receiver for Lunar Missions

    NASA Technical Reports Server (NTRS)

    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

  5. Taste Alteration in Patients Receiving Chemotherapy

    PubMed Central

    Sözeri, Elif; Kutlutürkan, Sevinç

    2015-01-01

    Objective This study is aimed to determine factors that affect conditions of patients receiving chemotherapy in terms of experienced taste alteration. Materials and Methods In this descriptive study, 184 patients receiving chemotherapy were included in the sample. Data were collected during the period of December 2013 to May 2014 using “Patient Characteristics Identification Form” and “Chemotherapy-induced Taste Alteration Scale (CiTAS).” The data were analyzed using SPSS 20 (SPSS Inc., Chicago IL, USA) statistical software in terms of number, percentage, Mann-Whitney U test, and Kruskal-Wallis H test. Results The mean age of the patients was 55.5±11.8 and 57.1% of them were female. The clinical diagnosis of the patients were most frequently breast cancer (n=46), colorectal cancer (n=45), and lung cancer (n=25). Furthermore, 37.5% of the patients were in clinical stage II; 15.8% of the patients received paclitaxel+herceptin and 14.1% received gemcitabine+cisplatin chemotherapy protocols. Data demonstrated significant differences in mean scores (p<0.05) taken from “Decline in Basic Taste” and “Phantogeusia and Parageusia” subscales with patients with or without xerostomia. There were significant differences in the average scores of the subscales between those with and without a sore mouth “Discomfort” and “General taste alterations” (p<0.05). Conclusion It has been established that patients receiving chemotherapy experience substantial alteration in taste by exposure of different subscales of CiTAS. Analysis of scores collected from different subscales of CiTAS with respect to sociodemographic and pathological differences showed that patients with xerostomia and sore mouth experienced more severe taste alterations.

  6. Signal processor for processing ultrasonic receiver signals

    DOEpatents

    Fasching, George E.

    1980-01-01

    A signal processor is provided which uses an analog integrating circuit in conjunction with a set of digital counters controlled by a precision clock for sampling timing to provide an improved presentation of an ultrasonic transmitter/receiver signal. The signal is sampled relative to the transmitter trigger signal timing at precise times, the selected number of samples are integrated and the integrated samples are transferred and held for recording on a strip chart recorder or converted to digital form for storage. By integrating multiple samples taken at precisely the same time with respect to the trigger for the ultrasonic transmitter, random noise, which is contained in the ultrasonic receiver signal, is reduced relative to the desired useful signal.

  7. Grooms receives 2011 Donald L. Turcotte Award

    NASA Astrophysics Data System (ADS)

    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.

  8. Graphene radio frequency receiver integrated circuit.

    PubMed

    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.

  9. Cryogenic Amplifier Based Receivers at Submillimeter Wavelengths

    NASA Technical Reports Server (NTRS)

    Chattopadhyay, Goutam; Reck, Theodore and; Schlecht, Erich; Lin, Robert; Deal, William

    2012-01-01

    The operating frequency of InP high electron mobility transistor (HEMT) based amplifiers has moved well in the submillimeter-wave frequencies over the last couple of years. Working amplifiers with usable gain in waveguide packages has been reported beyond 700 GHz. When cooled cryogenically, they have shown substantial improvement in their noise temperature. This has opened up the real possibility of cryogenic amplifier based heterodyne receivers at submillimeter wavelengths for ground-based, air-borne, and space-based instruments for astrophysics, planetary, and Earth science applications. This paper provides an overview of the science applications at submillimeter wavelengths that will benefit from this technology. It also describes the current state of the InP HEMT based cryogenic amplifier receivers at submillimeter wavelengths.

  10. North Dakota geology school receives major gift

    NASA Astrophysics Data System (ADS)

    Showstack, Randy

    2012-10-01

    Petroleum geology and related areas of study at the University of North Dakota (UND) received a huge financial boost with the announcement on 24 September of $14 million in private and public partnership funding. The university announced the naming of the Harold Hamm School of Geology and Geological Engineering, formerly a department within the College of Engineering and Mines, in recognition of $10 million provided as a gift by oilman Harold Hamm and Continental Resources, Inc. Hamm is the chair and chief executive officer of Continental, the largest leaseholder in the Bakken Play oil formation in North Dakota and Montana, and he is also an energy policy advisor to Republican presidential candidate Mitt Romney. UND also received $4 million from the Oil and Gas Research Program of the North Dakota Industrial Commission to support geology and geological engineering education and research.

  11. ICESat-2 / ATLAS Flight Science Receiver Algorithms

    NASA Astrophysics Data System (ADS)

    Mcgarry, J.; Carabajal, C. C.; Degnan, J. J.; Mallama, A.; Palm, S. P.; Ricklefs, R.; Saba, J. L.

    2013-12-01

    NASA's Advanced Topographic Laser Altimeter System (ATLAS) will be the single instrument on the ICESat-2 spacecraft which is expected to launch in 2016 with a 3 year mission lifetime. The ICESat-2 orbital altitude will be 500 km with a 92 degree inclination and 91-day repeat tracks. 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. Without some method of eliminating solar background noise in near real-time, the volume of ATLAS telemetry would far exceed the normal X-band downlink capability. To reduce the data volume to an acceptable level a set of onboard Receiver Algorithms has been developed. These Algorithms limit the daily data volume by distinguishing surface echoes from the background noise and allow the instrument to telemeter only a small vertical region about the signal. This is accomplished through the use of an onboard Digital Elevation Model (DEM), signal processing techniques, and an onboard relief map. Similar to what was flown on the ATLAS predecessor GLAS (Geoscience Laser Altimeter System) the DEM provides minimum and maximum heights for each 1 degree x 1 degree tile on the Earth. This information allows the onboard algorithm to limit its signal search to the region between minimum and maximum heights (plus some margin for errors). The understanding that the surface echoes will tend to clump while noise will be randomly distributed led us to histogram the received event times. The selection of the signal locations is based on those histogram bins with statistically significant counts. Once the signal location has been established the onboard Digital Relief Map (DRM) is used to determine the vertical width of the telemetry band about the signal. The ATLAS Receiver Algorithms are nearing completion of the development phase and are currently being tested using a Monte Carlo Software Simulator that models the instrument, the orbit and the environment

  12. Integrated Microphotonic Receiver for Ka-Band

    NASA Technical Reports Server (NTRS)

    Levi, A. F. J.

    2005-01-01

    This report consists of four main sections. Part I: LiNbO3 microdisk resonant optical modulator. Brief review of microdisk optical resonator and RF ring resonator. Microwave and photonic design challenges for achieving simultaneous RF-optical resonance are addressed followed by our solutions. Part II: Experimental demonstration of LiNbO3 microdisk modulator performance in wired and wireless RF-optical links. Part III: Microphotonic RF receiver architecture that exploits the nonlinear modulation in the LiNbO3 microdisk modulator to achieve direct photonic down-conversion from RF carrier without using any high-speed electronic elements. Part IV: Ultimate sensitivity of the microdisk photonic receiver and the future road map toward a practical device.

  13. Error probability performance of unbalanced QPSK receivers

    NASA Technical Reports Server (NTRS)

    Simon, M. K.

    1978-01-01

    A simple technique for calculating the error probability performance and associated noisy reference loss of practical unbalanced QPSK receivers is presented. The approach is based on expanding the error probability conditioned on the loop phase error in a power series in the loop phase error and then, keeping only the first few terms of this series, averaging this conditional error probability over the probability density function of the loop phase error. Doing so results in an expression for the average error probability which is in the form of a leading term representing the ideal (perfect synchronization references) performance plus a term proportional to the mean-squared crosstalk. Thus, the additional error probability due to noisy synchronization references occurs as an additive term proportional to the mean-squared phase jitter directly associated with the receiver's tracking loop. Similar arguments are advanced to give closed-form results for the noisy reference loss itself.

  14. Screen-printed flexible MRI receive coils

    PubMed Central

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

    2016-01-01

    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. PMID:26961073

  15. Screen-printed flexible MRI receive coils.

    PubMed

    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.

  16. Investigating EMI-Characteristics of Navigation Receivers

    NASA Astrophysics Data System (ADS)

    Geise, Robert; Kerfin, Oliver; Zimmer, Georg; Neubauer, Bjorn; Enders, Achim

    2016-05-01

    Typically, the investigations of electromagnetic interference (EMI) refer to single limit values that may not be exceeded at a receiver's input stage. In that manner the actual quality of a navigation signal is not assessed at all, neither related to individual disturbance levels that are not continuous wave. This contribution discusses test setups and configurations of how to measure the navigation signal quality including the dynamic and non-linear behaviour of navigation receivers.Measurement results are presented for the instrument landing system (ILS) and the VHF omni- directional radio range (VOR). In particular, the focus is on time-variant interferences that can occur either due to multipath propagation with rotating wind turbines or transient signals, such as noise.

  17. VLBI2010 Receiver Back End Comparison

    NASA Technical Reports Server (NTRS)

    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.

  18. Fused silica windows for solar receiver applications

    NASA Astrophysics Data System (ADS)

    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.

  19. The Portable Radio Science Receiver (RSR)

    NASA Astrophysics Data System (ADS)

    Rogstad, S.; Navarro, R.; Finley, S.; Goodhart, C.; Proctor, R.; Asmar, S.

    2009-08-01

    The radio science receiver (RSR) is an open-loop receiver that has been used in NASA's Deep Space Network (DSN) facilities for almost a decade and is a valuable resource used to record data for radio science experiments, radio astronomy observations, and very long baseline interferometry. In the last few years, NASA has needed to send RSRs to non-DSN facilities such as the Greenbank Telescope and Australia's Parkes and Narrabri antenna array for special events such as the Mars Exploration Rover entry, descent, and landing maneuver and the Huygens probe landing on Titan. The need to quickly and cost effectively ship and set up an RSR without taking away valuable existing DSN resources has led to the development of a prototype portable RSR (PRSR). The PRSR maintains most of the capabilities of a full RSR and greatly exceeds it in many ways while only a fraction of the cost and weight.

  20. Next generation receivers for the submillimeter array

    NASA Astrophysics Data System (ADS)

    Grimes, Paul; Blundell, Ray; Paine, Scott; Tong, C.-Y. Edward; Zeng, Lingzhen

    2016-07-01

    The Submillimeter Array (SMA) is an 8-element mm/sub-mm interferometer on the summit of Maunakea, Hawaii that is operated jointly by the Smithsonian Astrophysical Observatory (SAO) and the Academia Sinica Institute of Astronomy and Astrophysics (ASIAA). After nearly 13 years of operation, we are undertaking a major upgrade of the array's cryogenics, receivers and other systems that will enhance the science capabilities of the array and replace components reaching end-of-life. Here we describe the new receivers, containing dual-polarization, ultra-wideband SIS mixers operating at 230 and 345 GHz, the new ultra-wideband IF signal transport and correlator system, and the enhanced observing capabilities that will be enabled by this upgrade.

  1. Holevo Capacity Achieving Joint Detection Receiver

    DTIC Science & Technology

    2013-12-31

    and 1-a> + GENERATE MINIMUM PROBABILITY OF ERROR ,__,... 1320 (MPE) BASIS FOR CODEBOOK • EXTEND CODEWORDS OF CODEBOOK I_,... 1330 INTO A SET OF ALL...there exist error correction codes that allow a probability of error at a receiver to be made arbitrarily small. Thus, given the right error correction...probability of error (MPE) basis for the codebook; generating, by the computer device, a measurement unitary matrix for the codebook by expressing

  2. Air Brayton Solar Receiver, phase 1

    NASA Technical Reports Server (NTRS)

    Zimmerman, D. K.

    1979-01-01

    A six month analysis and conceptual design study of an open cycle Air Brayton Solar Receiver (ABSR) for use on a tracking, parabolic solar concentrator are discussed. The ABSR, which includes a buffer storage system, is designed to provide inlet air to a power conversion unit. Parametric analyses, conceptual design, interface requirements, and production cost estimates are described. The design features were optimized to yield a zero maintenance, low cost, high efficiency concept that will provide a 30 year operational life.

  3. Accounts receivable reports: underutilized mining tools.

    PubMed

    Wallace, R

    1999-01-01

    There is gold to be found in accounts receivable reports for those willing to mine the data. The key is to know how to interpret the information buried within the numbers and use it to recover monies owed. This article identifies seven reports that should be staples in every organization committed to improving its overall collection performance. Also included are tips on understanding reports and implementing changes.

  4. Optical antenna gain. II - Receiving antennas

    NASA Technical Reports Server (NTRS)

    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).

  5. Solar central receiver integration with Hoover Dam

    SciTech Connect

    Remmers, H.E.; Zelenka, R.L.; Kitchen, J.H.

    1980-01-01

    The technical and economic feasibility of integrating a 100 MWe solar central receiver powerplant located in Yuma, Arizona with the Hoover Dam hydroelectric power system is discussed. Technical feasibility was determined by evaluating the effects of integration on the hydrologic and power operations of the existing hydro system. Economic feasibility was determined by comparing the costs of the integrated system with that of the most likely alternative source of power generation--an oil-fired,combined-cycle plant.

  6. Robust quantum receivers for coherent state discrimination

    NASA Astrophysics Data System (ADS)

    Becerra, Francisco Elohim

    2014-05-01

    Quantum state discrimination is a central task for quantum information and is a fundamental problem in quantum mechanics. Nonorthogonal states, such as coherent states which have intrinsic quantum noise, cannot be discriminated with total certainty because of their intrinsic overlap. This nonorthogonality is at the heart of quantum key distribution for ensuring absolute secure communications between a transmitter and a receiver, and can enable many quantum information protocols based on coherent states. At the same time, while coherent states are used for communications because of their robustness to loss and simplicity of generation and detection, their nonorthogonality inherently produces errors in the process of decoding the information. The minimum error probability in the discrimination of nonorthogonal coherent states measured by an ideal lossless and noiseless conventional receiver is given by the standard quantum limit (SQL). This limit sets strict bounds on the ultimate performance of coherent communications and many coherent-state-based quantum information protocols. However, measurement strategies based on the quantum properties of these states can allow for better measurements that surpass the SQL and approach the ultimate measurement limits allowed by quantum mechanics. These measurement strategies can allow for optimally extracting information encoded in these states for coherent and quantum communications. We present the demonstration of a receiver based on adaptive measurements and single-photon counting that unconditionally discriminates multiple nonorthogonal coherent states below the SQL. We also discuss the potential of photon-number-resolving detection to provide robustness and high sensitivity under realistic conditions for an adaptive coherent receiver with detectors with finite photon-number resolution.

  7. Digital Signal Processor For GPS Receivers

    NASA Technical Reports Server (NTRS)

    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.

  8. Global Positioning System (GPS) Geodetic Receivers,

    DTIC Science & Technology

    1982-02-08

    Subti.) S. TYPE OF REPORT A PERFo COVERED Global Positioning System ( GPS ) Geodetic N/A Receivers S. PERFORMING OrG. REPORT NUMBER I N/A AUTNORf*) S...i N meueaed idautfy b block nmAr) The NAVSTAR Global Positioning System ( GPS ) when fully developed will pro- vide world-wide, all weather, continuous... Global Positioning System ( GPS ) when fully developed will provide world-wide, all weather, continuous, highly accurate radio navigation support to

  9. Radio Astronomy Software Defined Receiver Project

    SciTech Connect

    Vacaliuc, Bogdan; Leech, Marcus; Oxley, Paul; Flagg, Richard; Fields, David

    2011-01-01

    The paper describes a Radio Astronomy Software Defined Receiver (RASDR) that is currently under development. RASDR is targeted for use by amateurs and small institutions where cost is a primary consideration. The receiver will operate from HF thru 2.8 GHz. Front-end components such as preamps, block down-converters and pre-select bandpass filters are outside the scope of this development and will be provided by the user. The receiver includes RF amplifiers and attenuators, synthesized LOs, quadrature down converters, dual 8 bit ADCs and a Signal Processor that provides firmware processing of the digital bit stream. RASDR will interface to a user s PC via a USB or higher speed Ethernet LAN connection. The PC will run software that provides processing of the bit stream, a graphical user interface, as well as data analysis and storage. Software should support MAC OS, Windows and Linux platforms and will focus on such radio astronomy applications as total power measurements, pulsar detection, and spectral line studies.

  10. Optical antenna gain. 2: receiving antennas.

    PubMed

    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.

  11. Hypersensitivity reactions in patients receiving hemodialysis.

    PubMed

    Butani, Lavjay; Calogiuri, Gianfranco

    2017-06-01

    To describe hypersensitivity reactions in patients receiving maintenance hemodialysis. PubMed search of articles published during the past 30 years with an emphasis on publications in the past decade. Case reports and review articles describing hypersensitivity reactions in the context of hemodialysis. Pharmacologic agents are the most common identifiable cause of hypersensitivity reactions in patients receiving hemodialysis. These include iron, erythropoietin, and heparin, which can cause anaphylactic or pseudoallergic reactions, and topical antibiotics and anesthetics, which lead to delayed-type hypersensitivity reactions. Many hypersensitivity reactions are triggered by complement activation and increased bradykinin resulting from contact system activation, especially in the context of angiotensin-converting enzyme inhibitor use. Several alternative pharmacologic preparations and dialyzer membranes are available, such that once an etiology for the reaction is established, recurrences can be prevented without affecting the quality of care provided to patients. Although hypersensitivity reactions are uncommon in patients receiving hemodialysis, they can be life-threatening. Moreover, considering the large prevalence of the end-stage renal disease population, the implications of such reactions are enormous. Most reactions are pseudoallergic and not mediated by immunoglobulin E. The multiplicity of potential exposures and the complexity of the environment to which patients on dialysis are exposed make it challenging to identify the precise cause of these reactions. Great diligence is needed to investigate hypersensitivity reactions to avoid recurrence in this high-risk population. Copyright © 2017 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

  12. The experience of receiving therapeutic touch.

    PubMed

    Samarel, N

    1992-06-01

    The purpose of this qualitative study was to describe the patient's experience of receiving therapeutic touch (TT) treatments. The design was informed by phenomenology in the sense that it was searching for a definition of the lived experience of the phenomenon of TT. Data were obtained through one open-ended interview and a second clarifying interview of each subject. All data were subjected to content analysis. For participants, the lived experience of TT was described as a linear process that began with the perceived need for and decision to seek treatment. It progressed through one or more treatments and continued to have an impact upon the participants' lives. These findings were examined within the context of Martha Rogers' conceptual system. This study has shown that, for 20 participants receiving treatment, TT was a fulfilling multidimensional experience that facilitated personal growth. Such as experience can only enrich the lives of those who receive treatment. Certainly, a nursing intervention that can achieve such a positive influence has potential for use in all areas of nursing care and needs to be explored further.

  13. Transient simulation of molten salt central receiver

    NASA Astrophysics Data System (ADS)

    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.

  14. Cryogenic 160-GHz MMIC Heterodyne Receiver Module

    NASA Technical Reports Server (NTRS)

    Samoska, Lorene A.; Soria, Mary M.; Owen, Heather R.; Dawson, Douglas E.; Kangaslahti, Pekka P.; Gaier, Todd C.; Voll, Patricia; Lau, Judy; Sieth, Matt; Church, Sarah

    2011-01-01

    A cryogenic 160-GHz MMIC heterodyne receiver module has demonstrated a system noise temperature of 100 K or less at 166 GHz. This module builds upon work previously described in Development of a 150-GHz MMIC Module Prototype for Large-Scale CMB Radiation (NPO-47664), NASA Tech Briefs, Vol. 35, No. 8 (August 2011), p. 27. In the original module, the local oscillator signal was saturating the MMIC low-noise amplifiers (LNAs) with power. In order to suppress the local oscillator signal from reaching the MMIC LNAs, the W-band (75 110 GHz) signal had to be filtered out before reaching 140 170 GHz. A bandpass filter was developed to cover 120 170 GHz, using microstrip parallel-coupled lines to achieve the desired filter bandwidth, and ensure that the unwanted W-band local oscillator signal would be sufficiently suppressed. With the new bandpass filter, the entire receiver can work over the 140 180-GHz band, with a minimum system noise temperature of 460 K at 166 GHz. The module was tested cryogenically at 20 K ambient temperature, and it was found that the receiver had a noise temperature of 100 K over an 8-GHz bandwidth. The receiver module now includes a microstrip bandpass filter, which was designed to have a 3-dB bandwidth of approximately 120-170 GHz. The filter was fabricated on a 3-mil-thick alumina substrate. The filter design was based on a W-band filter design made at JPL and used in the QUIET (Q/U Imaging ExperimenT) radiometer modules. The W-band filter was scaled for a new center frequency of 150 GHz, and the microstrip segments were changed accordingly. Also, to decrease the bandwidth of the resulting scaled design, the center gaps between the microstrip lines were increased (by four micrometers in length) compared to the gaps near the edges. The use of the 150-GHz bandpass filter has enabled the receiver module to function well at room temperature. The system noise temperature was measured to be less than 600 K (at room temperature) from 154 to 168 GHz

  15. Solar receiver performance of point focusing collector system

    NASA Technical Reports Server (NTRS)

    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.

  16. Receivers Gather Data for Climate, Weather Prediction

    NASA Technical Reports Server (NTRS)

    2012-01-01

    Signals from global positioning system (GPS) satellites are now being used for more than just location and navigation information. By looking at the radio waves from GPS satellites, a technology developed at NASA s Jet Propulsion Laboratory (JPL) not only precisely calculates its position, but can also use a technique known as radio occultation to help scientists study the Earth s atmosphere and gravity field to improve weather forecasts, monitor climate change, and enhance space weather research. The University Corporation for Atmospheric Research (UCAR), a nonprofit group of universities in Boulder, Colorado, compares radio occultation to the appearance of a pencil when viewed though a glass of water. The water molecules change the path of visible light waves so that the pencil appears bent, just like molecules in the air bend GPS radio signals as they pass through (or are occulted by) the atmosphere. Through measurements of the amount of bending in the signals, scientists can construct detailed images of the ionosphere (the energetic upper part of the atmosphere) and also gather information about atmospheric density, pressure, temperature, and moisture. Once collected, this data can be input into weather forecasting and climate models for weather prediction and climate studies. Traditionally, such information is obtained through the use of weather balloons. In 1998, JPL started developing a new class of GPS space science receivers, called Black Jack, that could take precise measurements of how GPS signals are distorted or delayed along their way to the receiver. By 2006, the first demonstration of a GPS radio occultation constellation was launched through a collaboration among Taiwan s National Science Council and National Space Organization, the U.S. National Science Foundation, NASA, the National Oceanic and Atmospheric Administration (NOAA), and other Federal entities. Called the Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC

  17. Superconducting Submm Integrated Receiver for TELIS

    NASA Astrophysics Data System (ADS)

    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.

    2006-06-01

    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 a variety of atmospheric constituents of the stratosphere. The 550 - 650 GHz channel of TELIS is based on a phase-locked Superconducting Integrated Receiver (SIR). SIR is an on-chip combination of a low-noise Superconductor-Insulator-Superconductor (SIS) mixer with quasioptical antenna, a superconducting Flux Flow Oscillator (FFO) acting as Local Oscillator (LO), and SIS harmonic mixer (HM) for FFO phase locking. A number of new solutions were implemented in the new generation of SIR chips. To achieve the wide-band performance of the spectrometer, a side-feed twin-SIS mixer and balanced SIS mixer with 0.8 µm2 junctions integrated with a double-dipole (or double-slot) antenna is used. An improved design of the FFO for TELIS has been developed and optimized providing a free-running linewidth between 10 and 2 MHz in the frequency range 500 - 700 GHz. It is important to ensure that tuning of a phase-locked (PL) SIR can be performed remotely by telecommand. For this purpose a number of approaches for the PL SIR automatic computer control have been developed. All receiver components (including input optical elements and Martin-Puplett polarization rotating interferometer for single side band operation) will be mounted on a single 4.2 K plate inside a 40 × 180 × 80 mm3 box. First measurements give an uncorrected double side band (DSB) noise temperature below 250 K measured with the phase-locked FFO; more detailed results are presented at the conference.

  18. Aluminium speciation in effluents and receiving waters.

    PubMed

    Gardner, M J; Comber, S D W

    2003-12-01

    The respective speciation of aluminium in sewage effluent and in river water receiving effluent, has been examined. Results showed that concentrations of reactive aluminium changed over a timescale of hours and were controlled predominantly by pH. A minimum concentration of reactive aluminium occurred at a pH of approximately 6.8, coinciding with the prevalence of non-reactive, insoluble Al(OH)3 species. For receiving waters of low pH value, typically < pH 5, a large proportion of the 'naturally present' aluminium can be present in a reactive form at concentrations higher than the proposed Environmental Quality Standard (EQS). Mixing of waters of this type with effluent of a higher pH value leads to the precipitation of aluminium hydroxide. Mixing of effluent of pH value in the range 7.5-8.0 with river water in the same (or slightly higher) pH range appears to result in no appreciable change in the proportion of reactive aluminium; the change in concentration tends to be related simply to dilution. On the basis of a theoretical knowledge of aluminium speciation, results obtained in this work indicate that it is possible to make predictions about the proportion of reactive aluminium present in a receiving water, based on the pH values of the effluent water mixture and the concentration in the effluent. Reasonable comparisons between measured and predicted values were obtained at higher pH values, but the relationship was less certain at pH values less than 6.5 for which levels of reactive metal tended to be higher than the quality standard value.

  19. Flight evaluation: Ohio University omega receiver base

    NASA Technical Reports Server (NTRS)

    Chamberlin, K. A.; Lilley, R. W.; Salter, R. J.

    1974-01-01

    A flight evaluation is presented of the Ohio University Omega Receiver Base, developed under the NASA Tri-University Program in Air Transportation, to provide a vehicle for the transfer of flight-test data to NASA and to other participants in the Tri-University program. Chart recordings of flight data are given, along with chronological listings of significant events which occurred during the flight. Digital data was prepared in data-processing card form for distribution. Data include phase measurements from all eight Omega time-slots for the duration of the flight, plus event marks which serve to correlate the phase data with flight-path documentation.

  20. Solar energy receiver for a Stirling engine

    NASA Technical Reports Server (NTRS)

    Selcuk, M. K. (Inventor)

    1980-01-01

    A solar energy receiver includes a separable endless wall formed of a ceramic material in which a cavity of substantially cylindrical configuration is defined for entrapping solar flux. An acceptance aperture is adapted to admit to the cavity a concentrated beam of solar energy. The wall is characterized by at least one pair of contiguously related segments separated by lines of cleavage intercepting the aperture. At least one of the segments is supported for pivotal displacement. A thermal-responsive actuator is adapted to respond to excessive temperatures within the cavity for initiating pivoted displacement of one segment, whereby thermal flux is permitted to escape from the cavity.

  1. Reconfigurable Advanced Receiver Design and Implementation

    NASA Technical Reports Server (NTRS)

    Xu, Jianjing

    2005-01-01

    While the demand for real-time broadband information access has grown and continues to grow at a rapid Pace, the need for a reconfigurable receiver system has increased. To achieve the goal to communicate with multiple shuttles at a time, a filter bank in polyphase structure is introduced. This paper presents the design and implementation for high-speed, high-performance, and fixed-point polyphase filter banks. The polyphase filter structure is designed such that the use of a fixed-point system has minimum impact on the performance of the filter. The final hardware implementation is done on a Xilinx FPGA chip.

  2. MSW devices for EW receiver applications

    NASA Astrophysics Data System (ADS)

    Adam, J. D.

    A compressive electronic warfare receiver has been constructed using a magnetostatic wave (MSW) dispersive delay line and filter bank. Attention is presently given to the performance characteristics and potentialities of these devices with respect to dynamic range, probability of signal detection, and digital processing. Phase error and amplitude response improvements are noted to be required in order to achieve the full potential of this approach; in particular, the video outputs from a 1-GHz bandwidth delay line cannot be adequately processed by means of current electronic techniques.

  3. Line Focus Receiver Infrared Temperature Survey System

    SciTech Connect

    Wendelin, Tim

    2010-06-01

    For ongoing maintenance and performance purposes, solar parabolic trough field operators desire to know that the Heat Collection Elements (HCEs) are performing properly. Measuring their temperature is one way of doing this One 30MW field can contain approximately 10,000 HCE's. This software interfaces with a GPS receiver and an infrared camera. It takes global positioning data from the GPS and uses this information to automate the infrared image capture and temperature analysis of individual solar parabolic HCEs in a solar parabolic trough field With this software system an entire 30MW field can be surveyed in 2-3 days.

  4. GPS Receiver Performance Test at ROA

    DTIC Science & Technology

    2008-12-01

    models, and the capability to model second-order ionosphere effects. Then we used the NRCan 1087 software, provided by the Geodetic Survey Division...mentioned in the preceding section, two GTR50’s, one PolaRx2 GPS receiver, and a Symmetricom Active Hydrogen Maser (type MHM 2010) driven by a...solution, REF Clock (H- maser ) – IGST. 356 40th Annual Precise Time and Time Interval (PTTI) Meeting Figure 11. CV CGGTTS C/A GTR1-GTR3 in

  5. Advanced motor driven clamped borehole seismic receiver

    DOEpatents

    Engler, Bruce P.; Sleefe, Gerard E.; Striker, Richard P.

    1993-01-01

    A borehole seismic tool including a borehole clamp which only moves perpendicular to the borehole. The clamp is driven by an electric motor, via a right angle drive. When used as a seismic receiver, the tool has a three part housing, two of which are hermetically sealed. Accelerometers or geophones are mounted in one hermetically sealed part, the electric meter in the other hermetically sealed part, and the clamp and right angle drive in the third part. Preferably the tool includes cable connectors at both ends. Optionally a shear plate can be added to the clamp to extend the range of the tool.

  6. Lohman Receives 2013 Geodesy Section Award: Citation

    NASA Astrophysics Data System (ADS)

    Brown, Larry D.

    2014-09-01

    Rowena received her Ph.D. from the California Institute of Technology under the direction of Mark Simons, one of the pioneers in the relatively new field of satellite deformation imaging. In her own work, she has broken new ground by exploring the boundaries between geodesy and seismology. She has shown how the apparent disagreement between these two data types can provide novel insight into subsurface processes. For example, a discrepancy in seismic moment may indicate aseismic slip. Discrepancies in event locations can ferret out seismic mislocation biases with resulting improvement in global velocity models.

  7. Advanced motor driven clamped borehole seismic receiver

    DOEpatents

    Engler, B.P.; Sleefe, G.E.; Striker, R.P.

    1993-02-23

    A borehole seismic tool is described including a borehole clamp which only moves perpendicular to the borehole. The clamp is driven by an electric motor, via a right angle drive. When used as a seismic receiver, the tool has a three part housing, two of which are hermetically sealed. Accelerometers or geophones are mounted in one hermetically sealed part, the electric motor in the other hermetically sealed part, and the clamp and right angle drive in the third part. Preferably the tool includes cable connectors at both ends. Optionally a shear plate can be added to the clamp to extend the range of the tool.

  8. Diurnal measurements with prototype CMOS Omega receivers

    NASA Technical Reports Server (NTRS)

    Burhans, R. W.

    1976-01-01

    Diurnal signals from eight omega channels have been monitored at 10.2 KHz for selected station pairs. All eight Omega stations have been received at least 50 percent of the time over a 24 hour period during the month of October 1976. The data presented confirm the expected performance of the CMOS omega sensor processor in being able to digsignals out of a noisy environment. Of particular interest are possibilities for use of antipodal reception phenomena and a need for some ways of correcting for multi-modal propagation effects.

  9. A Mixer-Receiver for the Parametric Acoustic Receiving Array (PARRAY)

    DTIC Science & Technology

    1978-09-18

    oo NuMSIS _______ SEP05! I4 _ T~y~~~~f .~ ~ MIXER-BECEIVER FOR THE PARAMETRIC ACOUSTIC K ~~~~~ hnica l P.cP.rL) )RECEIVING ARRAY ( PARRAY ) ~~. I...ic receiver B PARRAY nonlinear acoustics $~~~~~~~t 5AC T ~CnntInu. on ,.v ~~.. •ld~ U n.c. .•I.y and Id.nSE~~ Ay bh~rA nu~~ba r) — — (U) A...receiver for a Parametric Acoustic Receiving Array ( PARRAY ’~ based on a high performance mixer appears to be well suited to the requirements of some PARRAY

  10. 7 CFR 46.18 - Record of produce received.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Record of produce received. 46.18 Section 46.18... Market Receivers § 46.18 Record of produce received. Market receivers shall keep in the order of receipt a record of all produce received and this record shall be in the form of a book (preferably a...

  11. Steam Rankine Solar Receiver, phase 2

    NASA Technical Reports Server (NTRS)

    Deanda, L. E.; Faust, M.

    1981-01-01

    A steam rankine solar receiver (SRSR) based on a tubular concept was designed and developed. The SRSR is an insulated, cylindrical coiled tube boiler which is mounted at the focal plane of a fully tracking parabolic solar reflector. The concentrated solar energy received at the focal plane is then transformed to thermal energy through steam generation. The steam is used in a small Rankine cycle heat engine to drive a generator for the production of electrical energy. The SRSR was designed to have a dual mode capability, performing as a once through boiler with and without reheat. This was achieved by means of two coils which constitute the boiler. The boiler core size of the SRSR is 17.0 inches in diameter and 21.5 inches long. The tube size is 7/16 inch I.D. by 0.070 inch wall for the primary, and 3/4 inch I.D. by 0.125 inch wall for the reheat section. The materials used were corrosion resistant steel (CRES) type 321 and type 347 stainless steel. The core is insulated with 6 inches of cerablanket insulation wrapped around the outer wall. The aperture end and the reflector back plate at the closed end section are made of silicon carbide. The SRSR accepts 85 kwth and has a design life of 10,000 hrs when producing steam at 1400 F and 2550 psig.

  12. Solar central receiver heliostat reflector assembly

    SciTech Connect

    Horton, R.H.; Zdeb, J.J.

    1980-06-24

    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 a 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. 14 figs.

  13. Solar central receiver heliostat reflector assembly

    SciTech Connect

    Horton, R.H.; Zdeb, J.J.

    1980-06-24

    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. 14 claims.

  14. Advanced Stirling receiver development program, phase 1

    NASA Technical Reports Server (NTRS)

    Lurio, Charles A.

    1990-01-01

    Critical technology experiments were designed and developed to evaluate the Stirling cavity heat pipe receiver for a space solar power system. Theoretical criteria were applied to the design of a module for containing energy storage phase change material while avoiding thermal ratcheting. Zero-g drop tower tests, without phase change, were conducted to affirm that the bubble location required to avoid ratcheting could be achieved without the use of container materials that are wetted by the phase change material. A full scale module was fabricated, but not tested. A fabrication method was successfully developed for the sodium evaporator dome, with a sintered screen wick, to be used as the focal point for the receiver. Crushing of the screen during hydroforming was substantially reduced over the results of other researchers by using wax impregnation. Superheating of the sodium in the wick under average flux conditions is expected to be under 10K. A 2000K furnace which will simulate solar flux conditions for testing the evaporator dome was successfully built and tested.

  15. Omnidirectional free-space optical receiver architecture

    NASA Astrophysics Data System (ADS)

    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.

  16. Awareness and education of patients receiving bisphosphonates.

    PubMed

    Bauer, Julia S; Beck, Nina; Kiefer, Julia; Stockmann, Philipp; Wichmann, Manfred; Eitner, Stephan

    2012-04-01

    Bisphosphonates are used to fight osteoporosis and for treating malignancies. In 2003, the first case reports appeared that described bisphosphonate-induced osteonecrosis of the jaw (BONJ). The aim of this study was to assess patient awareness of the adverse effects of bisphosphonates in order to improve cooperation among doctors and between doctors and patients. Patients with symptoms of osteoporosis, prostate cancer, or breast cancer were surveyed to determine their knowledge of bisphosphonates. The questionnaire comprised 12 questions that covered sociographic data, kind of medication, level of information, and side effects experienced. Out of 142 patients contacted, 55 participated in the study. 62% of patients received most of their knowledge about the prescribed drug from the package insert. Despite knowledge that the patient was under treatment with bisphosphonates, 80% of dental treatments were continued without modifications. Only 32% of patients that received intravenous bisphosphonate treatment were aware of the possible risks of developing BONJ. The level of information is poor concerning the side effects of bisphosphonates, particularly the risk of BONJ. Clinicians should aim to sensitize the relevant people about the risks before treatment. Copyright © 2011 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

  17. The 30-GHz monolithic receive module

    NASA Technical Reports Server (NTRS)

    Sokolov, V.; Geddes, J.; Bauhahn, P.

    1983-01-01

    Key requirements for a 30 GHz GaAs monolithic receive module for spaceborne communication antenna feed array applications include an overall receive module noise figure of 5 dB, a 30 dB RF to IF gain with six levels of intermediate gain control, a five-bit phase shifter, and a maximum power consumption of 250 mW. The RF designs for each of the four submodules (low noise amplifier, some gain control, phase shifter, and RF to IF sub-module) are presented. Except for the phase shifter, high frequency, low noise FETs with sub-half micron gate lengths are employed in the submodules. For the gain control, a two stage dual gate FET amplifier is used. The phase shifter is of the passive switched line type and consists of 5-bits. It uses relatively large gate width FETs (with zero drain to source bias) as the switching elements. A 20 GHz local oscillator buffer amplifier, a FET compatible balanced mixer, and a 5-8 GHz IF amplifier constitute the RF/IF sub-module. Phase shifter fabrication using ion implantation and a self-aligned gate technique is described. Preliminary RF results obtained on such phase shifters are included.

  18. Superconductor Digital-RF Receiver Systems

    NASA Astrophysics Data System (ADS)

    Mukhanov, Oleg A.; Kirichenko, Dmitri; Vernik, Igor V.; Filippov, Timur V.; Kirichenko, Alexander; Webber, Robert; Dotsenko, Vladimir; Talalaevskii, Andrei; Tang, Jia Cao; Sahu, Anubhav; Shevchenko, Pavel; Miller, Robert; Kaplan, Steven B.; Sarwana, Saad; Gupta, Deepnarayan

    Digital superconductor electronics has been experiencing rapid maturation with the emergence of smaller-scale, lower-cost communications applications which became the major technology drivers. These applications are primarily in the area of wireless communications, radar, and surveillance as well as in imaging and sensor systems. In these areas, the fundamental advantages of superconductivity translate into system benefits through novel Digital-RF architectures with direct digitization of wide band, high frequency radio frequency (RF) signals. At the same time the availability of relatively small 4K cryocoolers has lowered the foremost market barrier for cryogenically-cooled digital electronic systems. Recently, we have achieved a major breakthrough in the development, demonstration, and successful delivery of the cryocooled superconductor digital-RF receivers directly digitizing signals in a broad range from kilohertz to gigahertz. These essentially hybrid-technology systems combine a variety of superconductor and semiconductor technologies packaged with two-stage commercial cryocoolers: cryogenic Nb mixed-signal and digital circuits based on Rapid Single Flux Quantum (RSFQ) technology, room-temperature amplifiers, FPGA processing and control circuitry. The demonstrated cryocooled digital-RF systems are the world's first and fastest directly digitizing receivers operating with live satellite signals in X-band and performing signal acquisition in HF to L-band at ˜30GHz clock frequencies.

  19. Solar central receiver heliostat reflector assembly

    DOEpatents

    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.

  20. Advanced Stirling receiver development program, phase 1

    NASA Astrophysics Data System (ADS)

    Lurio, Charles A.

    1990-07-01

    Critical technology experiments were designed and developed to evaluate the Stirling cavity heat pipe receiver for a space solar power system. Theoretical criteria were applied to the design of a module for containing energy storage phase change material while avoiding thermal ratcheting. Zero-g drop tower tests, without phase change, were conducted to affirm that the bubble location required to avoid ratcheting could be achieved without the use of container materials that are wetted by the phase change material. A full scale module was fabricated, but not tested. A fabrication method was successfully developed for the sodium evaporator dome, with a sintered screen wick, to be used as the focal point for the receiver. Crushing of the screen during hydroforming was substantially reduced over the results of other researchers by using wax impregnation. Superheating of the sodium in the wick under average flux conditions is expected to be under 10K. A 2000K furnace which will simulate solar flux conditions for testing the evaporator dome was successfully built and tested.