Sample records for hemoglobinuria receiving eculizumab

  1. 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

  2. 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

  3. 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.

  4. Opportunity cost of funding drugs for rare diseases: the cost-effectiveness of eculizumab in paroxysmal nocturnal hemoglobinuria.

    PubMed

    Coyle, Doug; Cheung, Matthew C; Evans, Gerald A

    2014-11-01

    Both ethical and economics concerns have been raised with respect to the funding of drugs for rare diseases. This article reports both the cost-effectiveness of eculizumab for the treatment of paroxysmal nocturnal hemoglobinuria (PNH) and its associated opportunity costs. Analysis compared eculizumab plus current standard of care v. current standard of care from a publicly funded health care system perspective. A Markov model covered the major consequences of PNH and treatment. Cost-effectiveness was assessed in terms of the incremental cost per life year and per quality-adjusted life year (QALY) gained. Opportunity costs were assessed by the health gains foregone and the alternative uses for the additional resources. Eculizumab is associated with greater life years (1.13), QALYs (2.45), and costs (CAN$5.24 million). The incremental cost per life year and per QALY gained is CAN$4.62 million and CAN$2.13 million, respectively. Based on established thresholds, the opportunity cost of funding eculizumab is 102.3 discounted QALYs per patient funded. Sensitivity and subgroup analysis confirmed the robustness of the results. If the acquisition cost of eculizumab was reduced by 98.5%, it could be considered cost-effective. The nature of rare diseases means that data are often sparse for the conduct of economic evaluations. When data were limited, assumptions were made that biased results in favor of eculizumab. This study demonstrates the feasibility of conducting economic evaluations in the context of rare diseases. Eculizumab may provide substantive benefits to patients with PNH in terms of life expectancy and quality of life but at a high incremental cost and a substantial opportunity cost. Decision makers should fully consider the opportunity costs before making positive reimbursement decisions. © The Author(s) 2014.

  5. 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

  6. Therapeutic drug monitoring of eculizumab: Rationale for an individualized dosing schedule.

    PubMed

    Gatault, Philippe; Brachet, Guillaume; Ternant, David; Degenne, Danielle; Récipon, Guillaume; Barbet, Christelle; Gyan, Emmanuel; Gouilleux-Gruart, Valérie; Bordes, Cécile; Farrell, Alexandra; Halimi, Jean Michel; Watier, Hervé

    2015-01-01

    The annual cost of eculizumab maintenance therapy in paroxysmal nocturnal hemoglobinuria (PNH) and atypical hemolytic-uremic syndrome (aHUS) exceeds $300,000 per patient. A better understanding of eculizumab pharmacokinetics and subsequent individual dose adjustment could reduce this cost. We measured the trough eculizumab concentration in 9 patients with maintenance therapy (aHUS, n = 7; PNH, n = 2) and determined: 1) the intra- and inter-individual variability; 2) the influence of weight on eculizumab pharmacokinetics; and 3) the rate of elimination of eculizumab following discontinuation. A one-compartment model was developed to describe the pharmacokinetics of eculizumab and predicted complement activity by body weight. Trough eculizumab concentrations were >50 µg/mL in 9/9, >100 µg/mL in 8/9, and >300 µg/mL in 5/9 of patients. Intra-individual variability was low but eculizumab concentrations, closely correlated with patient weight (R(2) = 0.66, p = 0.034), varied broadly (55 ± 12 to 733 ± 164 µg/mL). Pharmacokinetic modeling showed that the elimination half-life varied greatly, with an increase from 7.8 d in a patient weighing 100 kg to 19.5 d in a 40 kg patient. We predicted that infusions of 1200 mg could be spaced every 4 or 6 weeks in patients weighing <90 and <70 kg, respectively. In this pilot study, the current recommended use of a fixed eculizumab dose for maintenance therapy is associated with excessively high trough concentrations in many patients. Further prospective larger studies are now required to support an individualized schedule adjusted for patient weight and based on the observed trough serum eculizumab concentration.

  7. Therapeutic drug monitoring of eculizumab: Rationale for an individualized dosing schedule

    PubMed Central

    Gatault, Philippe; Brachet, Guillaume; Ternant, David; Degenne, Danielle; Récipon, Guillaume; Barbet, Christelle; Gyan, Emmanuel; Gouilleux-Gruart, Valérie; Bordes, Cécile; Farrell, Alexandra; Halimi, Jean Michel; Watier, Hervé

    2015-01-01

    The annual cost of eculizumab maintenance therapy in paroxysmal nocturnal hemoglobinuria (PNH) and atypical hemolytic–uremic syndrome (aHUS) exceeds $300,000 per patient. A better understanding of eculizumab pharmacokinetics and subsequent individual dose adjustment could reduce this cost. We measured the trough eculizumab concentration in 9 patients with maintenance therapy (aHUS, n = 7; PNH, n = 2) and determined: 1) the intra- and inter-individual variability; 2) the influence of weight on eculizumab pharmacokinetics; and 3) the rate of elimination of eculizumab following discontinuation. A one-compartment model was developed to describe the pharmacokinetics of eculizumab and predicted complement activity by body weight. Trough eculizumab concentrations were >50 µg/mL in 9/9, >100 µg/mL in 8/9, and >300 µg/mL in 5/9 of patients. Intra-individual variability was low but eculizumab concentrations, closely correlated with patient weight (R2 = 0.66, p = 0.034), varied broadly (55 ± 12 to 733 ± 164 µg/mL). Pharmacokinetic modeling showed that the elimination half-life varied greatly, with an increase from 7.8 d in a patient weighing 100 kg to 19.5 d in a 40 kg patient. We predicted that infusions of 1200 mg could be spaced every 4 or 6 weeks in patients weighing <90 and <70 kg, respectively. In this pilot study, the current recommended use of a fixed eculizumab dose for maintenance therapy is associated with excessively high trough concentrations in many patients. Further prospective larger studies are now required to support an individualized schedule adjusted for patient weight and based on the observed trough serum eculizumab concentration. PMID:26337866

  8. Paroxysmal nocturnal hemoglobinuria clones in severe aplastic anemia patients treated with horse anti-thymocyte globulin plus cyclosporine

    PubMed Central

    Scheinberg, Phillip; Marte, Michael; Nunez, Olga; Young, Neal S.

    2010-01-01

    Background Clones of glycosylphosphatidylinositol-anchor protein-deficient cells are characteristic in paroxysmal nocturnal hemoglobinuria and are present in about 40–50% of patients with severe aplastic anemia. Flow cytometry has allowed for sensitive and precise measurement of glycosylphosphatidylinositol-anchor protein-deficient red blood cells and neutrophils in severe aplastic anemia. Design and Methods We conducted a retrospective analysis of paroxysmal nocturnal hemoglobinuria clones measured by flow cytometry in 207 consecutive severe aplastic anemia patients who received immunosuppressive therapy with a horse anti-thymocyte globulin plus cyclosporine regimen from 2000 to 2008. Results The presence of a glycosylphosphatidylinositol-anchor protein-deficient clone was detected in 83 (40%) patients pre-treatment, and the median clone size was 9.7% (interquartile range 3.5–29). In patients without a detectable clone pre-treatment, the appearance of a clone after immunosuppressive therapy was infrequent, and in most with a clone pre-treatment, clone size often decreased after immunosuppressive therapy. However, in 30 patients, an increase in clone size was observed after immunosuppressive therapy. The majority of patients with a paroxysmal nocturnal hemoglobinuria clone detected after immunosuppressive therapy did not have an elevated lactate dehydrogenase, nor did they experience hemolysis or thrombosis, and they did not require specific interventions with anticoagulation and/or eculizumab. Of the 7 patients who did require therapy for clinical paroxysmal nocturnal hemoglobinuria symptoms and signs, all had an elevated lactate dehydrogenase and a clone size greater than 50%. In all, 18 (8.6%) patients had a clone greater than 50% at any given time of sampling. Conclusions The presence of a paroxysmal nocturnal hemoglobinuria clone in severe aplastic anemia is associated with low morbidity and mortality, and specific measures to address clinical paroxysmal

  9. Eculizumab treatment and impaired opsonophagocytic killing of meningococci by whole blood from immunized adults.

    PubMed

    Konar, Monica; Granoff, Dan M

    2017-08-17

    Eculizumab, a humanized anti-complement C5 monoclonal antibody (mAb) for treatment of paroxysmal nocturnal hemoglobinuria (PNH) and atypical hemolytic uremic syndrome, blocks the terminal complement pathway required for serum bactericidal activity (SBA). Because treated patients are at >1000-fold increased risk of meningococcal disease, vaccination is recommended; whether vaccination can protect by opsonophagocytic activity in the absence of SBA is not known. Meningococci were added to anticoagulated blood from 12 healthy adults vaccinated with meningococcal serogroup B and serogroup A, C, W, Y vaccines. Bacterial survival was measured after 3-hour incubation in the presence of eculizumab or control complement factor D inhibitor ACH-4471, which blocks the complement alternative pathway (AP) and is in phase 2 development for treatment of PNH. In the absence of inhibitors, colony formation units (CFUs) per milliliter in blood from all 12 immunized subjects decreased from ∼4000 at time 0 to sterile cultures at 3 hours. In the presence of eculizumab, there was a >22-fold increase in geometric mean CFUs per milliliter (90 596 and 114 683 CFU/mL for serogroup B and C strains, respectively; P < .0001 compared with time 0). In the presence of ACH-4471, there was a >12-fold decrease (23 and 331 CFU/mL, respectively; P < .0001). The lack of meningococci killing by blood containing eculizumab resulted from inhibition of release of C5a, a C5 split product needed for upregulation of phagocytosis. The results provide an explanation for the large number of cases of meningococcal disease in immunized patients being treated with eculizumab and suggest that vaccination may provide better protection against meningococcal disease in patients treated with an AP-specific inhibitor. © 2017 by The American Society of Hematology.

  10. Presence of acute and chronic renal failure in patients with paroxysmal nocturnal hemoglobinuria: results of a retrospective analysis from the Spanish PNH Registry.

    PubMed

    Villegas, Ana; Núñez, Ramiro; Gaya, Anna; Cuevas-Ruiz, María Victoria; Bosch, José Miguel; Carral, Anna; Arrizabalaga, Beatriz; Gómez-Roncero, María Isabel; Mora, Asunción; Bravo, Pilar; Lavilla, Esperanza; Monteserín, Carmen; Hernández, Belén; Martínez-Barranco, Pilar; Jarque, Isidro; Urquía, María Anunciación; García-Donas, Gloria; Brunet, Salut; González, Fernando Ataulfo; Urbano, Álvaro

    2017-10-01

    Paroxysmal nocturnal hemoglobinuria (PNH) is a rare, life-threatening blood disease. With the advent of eculizumab treatment, renal function has substantially improved, although no data from real-world clinical practice are available. An observational, retrospective, multicenter study was conducted in Spain on clinical data obtained from outpatient visits of patients with PNH (Spanish PNH Registry) who had experienced acute (ARF) or chronic (CRF) renal failure. Of the 128 patients registered (April 2014), 60 were diagnosed with classic PNH. Twenty-seven (45.0%) patients with a mean age of 48.5 (±16.2) years had renal failure, ARF or CRF, and were included in this study. Near half of the patients (n = 13; 48.1%) presented with ARF alone, 33.3% (n = 9) had CRF with episodes of ARF, while 18.5% (n = 5) were diagnosed with CRF alone. For patients with diagnosis of PNH and renal failure (n = 27), the median time to the first ARF episode was 6.5 (CI 95%; 2.2, 14.9) years, whereas the median to the diagnosis of CRF was 14.5 (CI 95%; 3.8, 19.2) years after the diagnosis of PNH. Patients with ARF (n = 22) were treated with eculizumab and did not experience new episodes of ARF, except for one patient with sepsis. Of the patients with CRF, two received treatment without experiencing further episodes of ARF. Sixteen patients who completed treatment (11 with ARF and 5 with ARF + CRF) recovered from the episode of ARF or from CRF. Of the remaining patients treated with eculizumab, one patient improved from stages III to II, three patients stabilized without showing disease progression, and one patient progressed from stages III to IV. Treatment with eculizumab in PNH patients has beneficial effects on renal function, preventing ARF and progression to CRF.

  11. [Paroxysmal nocturnal hemoglobinuria: An unknown cause of thrombosis?].

    PubMed

    Doutrelon, C; Skopinski, S; Boulon, C; Constans, J; Viallard, J-F; Peffault de Latour, R

    2015-12-01

    Paroxysmal nocturnal hemoglobinuria (PNH) is a rare acquired disorder of hematopoietic stem cells. Somatic mutation in the phosphatidylinositol glycan class A (PIG-A), X-linked gene, is responsible for a deficiency in glycosphosphatidylinositol-anchored proteins (GPI-AP). The lack of one of the GPI-AP complement regulatory proteins (CD55, CD59) leads to hemolysis. The disease is diagnosed with hemolytic anemia, marrow failure and thrombosis. Thromboembolic complication occurs in 30% of patient after 10 years of follow-up and is the first event in one out of 10 patients. The two most common sites are hepatic and cerebral veins. These locations are correlated with high risk of death. Currently, these data are balanced with the use of a monoclonal antibody (Eculizumab), which has significantly improved the prognosis with a survival similar to general population after 36 months of follow-up. Anticoagulant treatment is recommended after a thromboembolic event but has no place in primary prophylaxis. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  12. Hemoglobinuria test

    MedlinePlus

    ... If the level of hemoglobin in the blood rises too high, then hemoglobin begins to appear in the urine. This is called hemoglobinuria. This test may be used to help diagnose causes of hemoglobinuria.

  13. Paroxysmal cold hemoglobinuria (PCH)

    MedlinePlus

    ... page: //medlineplus.gov/ency/article/000557.htm Paroxysmal cold hemoglobinuria (PCH) To use the sharing features on this page, please enable JavaScript. Paroxysmal cold hemoglobinuria (PCH) is a rare blood disorder in ...

  14. Hemoglobinuria Misidentified as Hematuria: Review of Discolored Urine and Paroxysmal Nocturnal Hemoglobinuria

    PubMed Central

    Veerreddy, Prashant

    2013-01-01

    Discolored urine is a common reason for office visits to a primary care physician and urology referral. Early differentiation of the type or cause of discolored urine is necessary for accurate diagnosis and prompt management. Paroxysmal nocturnal hemoglobinuria is a clonal disorder caused by acquired somatic mutations in the PIG-A gene on the X- chromosome of hemopoietic stem cells and leads to deficiency of surface membrane anchor proteins. The deficiency of these proteins leads to an increased risk of hemolysis of erythrocytes and structural damage of platelets, resulting in a clinical syndrome characterized by complement-mediated intravascular hemolytic anemia, bone marrow failure, and venous thrombosis. Patients with this clinical syndrome present with paroxysms of hemolysis, causing hemoglobinuria manifesting as discolored urine. This can be easily confused with other common causes of discolored urine and result in extensive urologic work-up. Three commonly confused entities of discolored urine include hematuria, hemoglobinuria, and myoglobinuria. Specific characteristics in a dipstick test or urinalysis can guide differentiation of these three causes of discolored urine. This article begins with a case summary of a woman presenting with cranberry-colored urine and a final delayed diagnosis of paryxysmal nocturnal hemoglobinuria. Her hemoglobinuria was misdiagnosed as hematuria, leading to extensive urologic work-up. The article also gives an overview of the approach to diagnosing and treating discolored urine. PMID:25512715

  15. 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.

  16. 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.

  17. Atypical haemolytic uraemic syndrome treated with the complement inhibitor eculizumab: the experience of the Australian compassionate access cohort.

    PubMed

    Mallett, A; Hughes, P; Szer, J; Tuckfield, A; Van Eps, C; Cambell, S B; Hawley, C; Burke, J; Kausman, J; Hewitt, I; Parnham, A; Ford, S; Isbel, N

    2015-10-01

    This study aimed to report the clinical characteristics and outcomes of Australian patients treated with eculizumab for atypical haemolytic uraemic syndrome (aHUS). A retrospective cohort study was undertaken of all patients in Australia treated with eculizumab provided in a compassionate access programme for a clinical diagnosis of aHUS using prospectively collected clinical data. A total of 10 patients with a median age of 23.5 years (interquartile range (IQR) 24.83 years) received compassionate access eculizumab for aHUS in Australia. Eight patients were female, and three had a family history of aHUS. Three received eculizumab for an initial acute aHUS presentation, three for relapsing and refractory acute aHUS, two for de novo aHUS post-renal transplantation, and one each for aHUS recurrence post-transplantation and facilitation of transplantation with a history of aHUS. The median duration of eculizumab therapy has been 911.5 days (IQR 569 days) with a cumulative exposure of 9184 days. At baseline all patients had renal and extra-renal aHUS involvement, with up to three non-renal organs affected. All but one patient, who died from uncontrollable gastrointestinal aHUS manifestations, have continued. The nine continuing patients achieved remission of aHUS. Two of the four patients requiring renal replacement therapy (RRT) at eculizumab commencement subsequently ceased RRT. Clinical events occurring in this cohort while on eculizumab treatment included neutropenia (two), posterior reversible encephalopathy syndrome (one), cardiomyopathy (one), pulmonary embolus (one), antibody-mediated rejection resulting in renal graft failure (one), iron deficiency (one), gastrointestinal haemorrhage (one) and death (one). Eculizumab has been an effective therapy for aHUS in this cohort, including when other therapies have failed. © 2015 Royal Australasian College of Physicians.

  18. Eculizumab Injection

    MedlinePlus

    ... myasthenia gravis (MG; a disorder of the nervous system that causes muscle weakness). Eculizumab injection is in a group of medications called monoclonal antibodies. It works by blocking the activity of the part of the immune system that may damage blood cells in people with ...

  19. Safety and efficacy of eculizumab in Guillain-Barré syndrome: a multicentre, double-blind, randomised phase 2 trial.

    PubMed

    Misawa, Sonoko; Kuwabara, Satoshi; Sato, Yasunori; Yamaguchi, Nobuko; Nagashima, Kengo; Katayama, Kanako; Sekiguchi, Yukari; Iwai, Yuta; Amino, Hiroshi; Suichi, Tomoki; Yokota, Takanori; Nishida, Yoichiro; Kanouchi, Tadashi; Kohara, Nobuo; Kawamoto, Michi; Ishii, Junko; Kuwahara, Motoi; Suzuki, Hidekazu; Hirata, Koichi; Kokubun, Norito; Masuda, Ray; Kaneko, Juntaro; Yabe, Ichiro; Sasaki, Hidenao; Kaida, Ken-Ichi; Takazaki, Hiroshi; Suzuki, Norihiro; Suzuki, Shigeaki; Nodera, Hiroyuki; Matsui, Naoko; Tsuji, Shoji; Koike, Haruki; Yamasaki, Ryo; Kusunoki, Susumu

    2018-06-01

    Despite the introduction of plasmapheresis and immunoglobulin therapy, many patients with Guillain-Barré syndrome still have an incomplete recovery. Evidence from pathogenesis studies suggests the involvement of complement-mediated peripheral nerve damage. We aimed to investigate the safety and efficacy of eculizumab, a humanised monoclonal antibody against the complement protein C5, in patients with severe Guillain-Barré syndrome. This study was a 24 week, multicentre, double-blind, placebo-controlled, randomised phase 2 trial done at 13 hospitals in Japan. Eligible patients with Guillain-Barré syndrome were aged 18 years or older and could not walk independently (Guillain-Barré syndrome functional grade 3-5). Patients were randomly assigned (2:1) to receive 4 weeks of intravenous immunoglobulin plus either eculizumab (900 mg) or placebo; randomisation was done via a computer-generated process and web response system with minimisation for functional grade and age. The study had a parallel non-comparative single-arm outcome measure. The primary outcomes were efficacy (the proportion of patients with restored ability to walk independently [functional grade ≤2] at week 4) in the eculizumab group and safety in the full analysis set. For the efficacy endpoint, we predefined a response rate threshold of the lower 90% CI boundary exceeding 50%. This trial is registered with ClinicalTrials.gov, number, NCT02493725. Between Aug 10, 2015, and April 21, 2016, 34 patients were assigned to receive either eculizumab (n=23) or placebo (n=11). At week 4, the proportion of the patients able to walk independently (functional grade ≤2) was 61% (90% CI 42-78; n=14) in the eculizumab group, and 45% (20-73; n=5) in the placebo group. Adverse events occurred in all 34 patients. Three patients had serious adverse events: two in the eculizumab group (anaphylaxis in one patient and intracranial haemorrhage and abscess in another patient) and one in the placebo group (depression

  20. 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

  1. Pathogenic Variants in Complement Genes and Risk of Atypical Hemolytic Uremic Syndrome Relapse after Eculizumab Discontinuation.

    PubMed

    Fakhouri, Fadi; Fila, Marc; Provôt, François; Delmas, Yahsou; Barbet, Christelle; Châtelet, Valérie; Rafat, Cédric; Cailliez, Mathilde; Hogan, Julien; Servais, Aude; Karras, Alexandre; Makdassi, Raifah; Louillet, Feriell; Coindre, Jean-Philippe; Rondeau, Eric; Loirat, Chantal; Frémeaux-Bacchi, Véronique

    2017-01-06

    The complement inhibitor eculizumab has dramatically improved the outcome of atypical hemolytic uremic syndrome. However, the optimal duration of eculizumab treatment in atypical hemolytic uremic syndrome remains debated. We report on the French atypical hemolytic uremic syndrome working group's first 2-year experience with eculizumab discontinuation in patients with atypical hemolytic uremic syndrome. Using the French atypical hemolytic uremic syndrome registry database, we retrospectively identified all dialysis-free patients with atypical hemolytic uremic syndrome who discontinued eculizumab between 2010 and 2014 and reviewed their relevant clinical and biologic data. The decision to discontinue eculizumab was made by the clinician in charge of the patient. All patients were closely monitored by regular urine dipsticks and blood tests. Eculizumab was rapidly (24-48 hours) restarted in case of relapse. Among 108 patients treated with eculizumab, 38 patients (nine children and 29 adults) discontinued eculizumab (median treatment duration of 17.5 months). Twenty-one patients (55%) carried novel or rare complement genes variants. Renal recovery under eculizumab was equally good in patients with and those without complement gene variants detected. After a median follow-up of 22 months, 12 patients (31%) experienced atypical hemolytic uremic syndrome relapse. Eight of 11 patients (72%) with complement factor H variants, four of eight patients (50%) with membrane cofactor protein variants, and zero of 16 patients with no rare variant detected relapsed. In relapsing patients, early reintroduction (≤48 hours) of eculizumab led to rapid (<7 days) hematologic remission and a return of serum creatinine to baseline level in a median time of 26 days. At last follow-up, renal function remained unchanged in nonrelapsing and relapsing patients compared with baseline values before eculizumab discontinuation. Pathogenic variants in complement genes were associated with higher

  2. Terminal Complement Blockade after Hematopoietic Stem Cell Transplantation Is Safe without Meningococcal Vaccination.

    PubMed

    Jodele, Sonata; Dandoy, Christopher E; Danziger-Isakov, Lara; Myers, Kasiani C; El-Bietar, Javier; Nelson, Adam; Wallace, Gregory; Teusink-Cross, Ashley; Davies, Stella M

    2016-07-01

    Eculizumab inhibits terminal complement-mediated intravascular hemolysis in patients with paroxysmal nocturnal hemoglobinuria and complement-mediated thrombotic microangiopathy (TMA) in patients with atypical hemolytic uremic syndrome and is now used as a first-line therapy in these diseases. Eculizumab is available only through a restricted program under a Risk Evaluation and Mitigation Strategy (REMS) because of an increased risk of meningococcal infections in persons without adequate functional complement. Administration of meningococcal vaccine is required at least 2 weeks before administering the first dose of eculizumab, and this advice is included in the product label. Eculizumab use for treatment of TMA in hematopoietic stem cell transplantation (HSCT) recipients brings a significant dilemma regarding REMS required meningococcal vaccination. TMA after HSCT usually occurs within the first 100 days after transplantation when patients are severely immunocompromised and are not able to mount a response to vaccines. We evaluated 30 HSCT recipients treated with eculizumab for high-risk TMA without meningococcal vaccine. All patients received antimicrobial prophylaxis adequate for Neisseria meningitides during eculizumab therapy and for 8 weeks after discontinuation of the drug. Median time to TMA diagnosis was 28 days after transplant (range, 13.8 to 48.5). Study subjects received a median of 14 eculizumab doses (range, 2 to 38 doses) for HSCT-associated TMA therapy. There were no incidences of meningococcal infections. The incidences of bacterial and fungal bloodstream infections were similar in patients treated with eculizumab (n = 30) as compared with those with HSCT-associated TMA who did not receive any complement blocking therapy (n = 39). Our data indicate that terminal complement blockade in the early post-transplant period can be performed without meningococcal vaccination while using appropriate antimicrobial prophylaxis until complement

  3. 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

  4. Use of eculizumab in a systemic lupus erythemathosus patient presenting thrombotic microangiopathy and heterozygous deletion in CFHR1-CFHR3. A case report and systematic review.

    PubMed

    de Holanda, Maria Izabel; Pôrto, Luis Cristóvão; Wagner, Teresa; Christiani, Luis Fernando; Palma, Lilian M P

    2017-12-01

    The association of thrombotic microangiopathy (TMA) with systemic lupus erythematosus (SLE) has been described in 0.5 to 10% of cases, and patients present worse outcome. TMA is described as the association of microangiopathic hemolytic anemia, thrombocytopenia, and an organ injury, frequently the kidney. This study describes a successful case of use of eculizumab in a patient with SLE and TMA refractory to standard therapy, and provides a literature review. Case description and search in PubMed and MEDLINE using systemic lupus erythemathous and/or antiphospholipid syndrome (APS) and eculizumab retrieved 15 case reports. Eighteen-year-old female presented acute renal failure and TMA and was diagnosed with SLE. Steroids and IV cyclophosphamide were started together with plasma exchange. After 55 days, she still persisted with microangiopathic anemia, thrombocytopenia, and anuria, and eculizumab was introduced. She had rapid improvement in hematological parameters, and dialysis was discontinued 25 days after the first dose. Genetic analysis showed large heterozygous deletion encompassing the entire CFHR1 and CFHR3, a finding previously associated with patients presenting atypical hemolytic-uremic syndrome (aHUS). Twenty patients who received eculizumab with SLE and/or APS have been published to date: 11 were female and mean age at presentation was 31 years. Seven out of the 20 patients presented only SLE, 5 patients only APS and 8 patients both SLE and APS. Eighteen patients underwent plasma exchange, with a mean of 20 (4-120) sessions per patient. Thirteen patients received rituximab. Hematological response was evident in 100% and kidney recovery in 85% of patients. The terminal complement blockade with eculizumab is an optional treatment for patients with SLE and/or APS presenting TMA and refractory to current immunosuppression therapies. Genetic testing may help recognize patients with aHUS and SLE/APS and therefore help to determine length of treatment with

  5. Eculizumab for dense deposit disease and C3 glomerulonephritis.

    PubMed

    Bomback, Andrew S; Smith, Richard J; Barile, Gaetano R; Zhang, Yuzhou; Heher, Eliot C; Herlitz, Leal; Stokes, M Barry; Markowitz, Glen S; D'Agati, Vivette D; Canetta, Pietro A; Radhakrishnan, Jai; Appel, Gerald B

    2012-05-01

    The principle defect in dense deposit disease and C3 glomerulonephritis is hyperactivity of the alternative complement pathway. Eculizumab, a monoclonal antibody that binds to C5 to prevent formation of the membrane attack complex, may prove beneficial. In this open-label, proof of concept efficacy and safety study, six subjects with dense deposit disease or C3 glomerulonephritis were treated with eculizumab every other week for 1 year. All had proteinuria >1 g/d and/or AKI at enrollment. Subjects underwent biopsy before enrollment and repeat biopsy at the 1-year mark. The subjects included three patients with dense deposit disease (including one patient with recurrent dense deposit disease in allograft) and three patients with C3 glomerulonephritis (including two patients with recurrent C3 glomerulonephritis in allograft). Genetic and complement function testing revealed a mutation in CFH and MCP in one subject each, C3 nephritic factor in three subjects, and elevated levels of serum membrane attack complex in three subjects. After 12 months, two subjects showed significantly reduced serum creatinine, one subject achieved marked reduction in proteinuria, and one subject had stable laboratory parameters but histopathologic improvements. Elevated serum membrane attack complex levels normalized on therapy and paralleled improvements in creatinine and proteinuria. Clinical and histopathologic data suggest a response to eculizumab in some but not all subjects with dense deposit disease and C3 glomerulonephritis. Elevation of serum membrane attack complex before treatment may predict response. Additional research is needed to define the subgroup of dense deposit disease/C3 glomerulonephritis patients in whom eculizumab therapy can be considered.

  6. Eculizumab for Dense Deposit Disease and C3 Glomerulonephritis

    PubMed Central

    Smith, Richard J.; Barile, Gaetano R.; Zhang, Yuzhou; Heher, Eliot C.; Herlitz, Leal; Stokes, M. Barry; Markowitz, Glen S.; D’Agati, Vivette D.; Canetta, Pietro A.; Radhakrishnan, Jai; Appel, Gerald B.

    2012-01-01

    Summary Background and objectives The principle defect in dense deposit disease and C3 glomerulonephritis is hyperactivity of the alternative complement pathway. Eculizumab, a monoclonal antibody that binds to C5 to prevent formation of the membrane attack complex, may prove beneficial. Design, setting, participants, & measurements In this open-label, proof of concept efficacy and safety study, six subjects with dense deposit disease or C3 glomerulonephritis were treated with eculizumab every other week for 1 year. All had proteinuria >1 g/d and/or AKI at enrollment. Subjects underwent biopsy before enrollment and repeat biopsy at the 1-year mark. Results The subjects included three patients with dense deposit disease (including one patient with recurrent dense deposit disease in allograft) and three patients with C3 glomerulonephritis (including two patients with recurrent C3 glomerulonephritis in allograft). Genetic and complement function testing revealed a mutation in CFH and MCP in one subject each, C3 nephritic factor in three subjects, and elevated levels of serum membrane attack complex in three subjects. After 12 months, two subjects showed significantly reduced serum creatinine, one subject achieved marked reduction in proteinuria, and one subject had stable laboratory parameters but histopathologic improvements. Elevated serum membrane attack complex levels normalized on therapy and paralleled improvements in creatinine and proteinuria. Conclusions Clinical and histopathologic data suggest a response to eculizumab in some but not all subjects with dense deposit disease and C3 glomerulonephritis. Elevation of serum membrane attack complex before treatment may predict response. Additional research is needed to define the subgroup of dense deposit disease/C3 glomerulonephritis patients in whom eculizumab therapy can be considered. PMID:22403278

  7. Clinical benefit of eculizumab in patients with no transfusion history in the International Paroxysmal Nocturnal Haemoglobinuria Registry.

    PubMed

    Almeida, Antonio M; Bedrosian, Camille; Cole, Alexander; Muus, Petra; Schrezenmeier, Hubert; Szer, Jeff; Rosse, Wendell F

    2017-09-01

    Eculizumab reduces intravascular haemolysis and improves disease symptoms in patients with paroxysmal nocturnal haemoglobinuria (PNH). To characterise, in a real-world setting, the effect of eculizumab in patients with haemolytic PNH (lactase dehydrogenase (LDH) ≥ 1.5 upper limit of normal) and no history of red blood cell transfusion, including those with high disease activity (HDA). Three populations from the International PNH Registry were studied: (i) non-transfused, untreated; (ii) non-transfused, eculizumab-treated and (iii) transfused, eculizumab-treated (≥1 transfusions in 6 months prior to eculizumab initiation). Using multivariate linear regression, the primary outcome was mean absolute change from baseline to 6 months in LDH (U/L) in non-transfused patients who were treated with eculizumab versus those who remained untreated. Secondary outcomes were mean changes in functional assessment of chronic illness therapy (FACIT)-Fatigue and European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC-QLQ)-C30 Fatigue scores from baseline to last available assessment. The study population included (i) 144 non-transfused, untreated patients; (ii) 45 non-transfused, eculizumab-treated patients and (iii) 105 transfused, eculizumab-treated patients. Of these, 136/144, 43/45 and 99/105 had HDA respectively. Compared with untreated patients, non-transfused, treated patients had greater absolute reduction in LDH (-1318.8 vs -39.4; P < 0.001) and greater percentage reduction in LDH (-69.9 vs -1.6%; P < 0.001). Clinically meaningful improvements in FACIT-Fatigue (73.7 vs 24.6%, respectively) and in EORTC-QLQ-C30 (84.2 vs 33.3%, respectively) were observed. Non-transfused, treated patients with HDA had significantly reduced LDH levels (P < 0.001) and clinically meaningful improvements in FACIT-Fatigue (P = 0.003) and EORTC-QLQ-C30 (P = 0.020) versus untreated patients. Significant LDH reduction and

  8. Prophylactic eculizumab for kidney transplantation in a child with atypical hemolytic uremic syndrome due to complement factor H mutation.

    PubMed

    Ranch, Daniel; Crowther, Barrett; Arar, Mazen; Assanasen, Chatchawin

    2014-09-01

    We present a case of successful deceased-donor kidney transplantation in a three-yr-old child with aHUS due to complement factor H mutation, using only prophylactic eculizumab treatment prior to transplant. She developed disease exacerbation in the immediate post-operative period despite having therapeutic eculizumab concentrations and evidence for complete complement pathway blockade. The patient responded well to additional doses of eculizumab and has maintained excellent graft function and disease control in the first year post-transplantation. The optimal dosing scheme for eculizumab in the perioperative period remains to be determined. More sensitive biomarkers of early disease activity are needed to improve disease monitoring. Finally, the duration of eculizumab therapy in patients with aHUS remains to be determined. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  9. 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.

  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. Safety and efficacy of eculizumab in anti-acetylcholine receptor antibody-positive refractory generalised myasthenia gravis (REGAIN): a phase 3, randomised, double-blind, placebo-controlled, multicentre study.

    PubMed

    Howard, James F; Utsugisawa, Kimiaki; Benatar, Michael; Murai, Hiroyuki; Barohn, Richard J; Illa, Isabel; Jacob, Saiju; Vissing, John; Burns, Ted M; Kissel, John T; Muppidi, Srikanth; Nowak, Richard J; O'Brien, Fanny; Wang, Jing-Jing; Mantegazza, Renato

    2017-12-01

    , staff, and outcome assessors were masked to treatment assignment. The primary efficacy endpoint was the change from baseline to week 26 in MG-ADL total score measured by worst-rank ANCOVA. The efficacy population set was defined as all patients randomly assigned to treatment groups who received at least one dose of study drug, had a valid baseline MG-ADL assessment, and at least one post-baseline MG-ADL assessment. The safety analyses included all randomly assigned patients who received eculizumab or placebo. This trial is registered with ClinicalTrials.gov, number NCT01997229. Between April 30, 2014, and Feb 19, 2016, we randomly assigned and treated 125 patients, 62 with eculizumab and 63 with placebo. The primary analysis showed no significant difference between eculizumab and placebo (least-squares mean rank 56·6 [SEM 4·5] vs 68·3 [4·5]; rank-based treatment difference -11·7, 95% CI -24·3 to 0·96; p=0·0698). No deaths or cases of meningococcal infection occurred during the study. The most common adverse events in both groups were headache and upper respiratory tract infection (ten [16%] for both events in the eculizumab group and 12 [19%] for both in the placebo group). Myasthenia gravis exacerbations were reported by six (10%) patients in the eculizumab group and 15 (24%) in the placebo group. Six (10%) patients in the eculizumab group and 12 (19%) in the placebo group required rescue therapy. The change in the MG-ADL score was not statistically significant between eculizumab and placebo, as measured by the worst-rank analysis. Eculizumab was well tolerated. The use of a worst-rank analytical approach proved to be an important limitation of this study since the secondary and sensitivity analyses results were inconsistent with the primary endpoint result; further research into the role of complement is needed. Alexion Pharmaceuticals. Copyright © 2017 Elsevier Ltd. All rights reserved.

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

    PubMed Central

    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

    2015-01-01

    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. PMID:26315930

  13. 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. Copyright© Ferrata Storti Foundation.

  14. QMG and MG-ADL correlations: Study of eculizumab treatment of myasthenia gravis.

    PubMed

    Howard, James F; Freimer, Miriam; O'Brien, Fanny; Wang, Jing Jing; Collins, Stephen R; Kissel, John T

    2017-08-01

    A phase 2 study of eculizumab for treating myasthenia gravis (MG) used the quantitative myasthenia gravis score (QMG) and myasthenia gravis activities of daily living profile (MG-ADL) to evaluate baseline disease severity and treatment response. Correlations were then analyzed between these assessments. Patients were given eculizumab or placebo during the first 16-week treatment period of the crossover study, with treatment assignments reversed for the second treatment period following a 5-week washout. QMG and MG-ADL scores at baseline and endpoint of each treatment period generated correlation coefficients for baseline status and treatment response during eculizumab therapy. Correlation strength between QMG and MG-ADL scores was higher for treatment response (R = 0.726; 95% confidence interval, 0.264-0.907; P = 0.0036) than for assessing baseline disease status (R = 0.552; 95% confidence interval, -0.022-0.839; P = 0.0495). MG-ADL may be more sensitive for assessing treatment response than point-in-time disease status. Muscle Nerve 56: 328-330, 2017. © 2016 Wiley Periodicals, Inc.

  15. Eculizumab for drug-induced de novo posttransplantation thrombotic microangiopathy: A case report.

    PubMed

    Safa, Kassem; Logan, Merranda S; Batal, Ibrahim; Gabardi, Steven; Rennke, Helmut G; Abdi, Reza

    2015-02-01

    De novo thrombotic microangiopathy (TMA) following renal transplantation is a severe complication associated with high rates of allograft failure. Several immunosuppressive agents are associated with TMA. Conventional approaches to managing this entity, such as withdrawal of the offending agent and/or plasmapheresis, often offer limited help, with high rates of treatment failure and graft loss. We herein report a case of drug induced de novo TMA successfully treated using the C5a inhibitor eculizumab in a renal transplant patient. This report highlights a potentially important role for eculizumab in settings where drug-induced de novo TMA is refractory to conventional therapies.

  16. 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

  17. Detection of paroxysmal nocturnal hemoglobinuria clones in patients with myelodysplastic syndromes and related bone marrow diseases, with emphasis on diagnostic pitfalls and caveats

    PubMed Central

    Wang, Sa A.; Pozdnyakova, Olga; Jorgensen, Jeffrey L.; Medeiros, L. Jeffrey; Stachurski, Dariusz; Anderson, Mary; Raza, Azra; Woda, Bruce A.

    2009-01-01

    Background The presence of paroxysmal nocturnal hemoglobinuria clones in the setting of aplastic anemia or myelodysplastic syndrome has been shown to have prognostic and therapeutic implications. However, the status of paroxysmal nocturnal hemoglobinuria clones in various categories of myelodysplastic syndrome and in other bone marrow disorders is not well-studied. Design and Methods By using multiparameter flow cytometry immunophenotypic analysis with antibodies specific for four glycosylphosphatidylinositol-anchored proteins (CD55, CD59, CD16, CD66b) and performing an aerolysin lysis confirmatory test in representative cases, we assessed the paroxysmal nocturnal hemoglobinuria-phenotype granulocytes in 110 patients with myelodysplastic syndrome, 15 with myelodysplastic/myeloproliferative disease, 5 with idiopathic myelofibrosis and 6 with acute myeloid leukemia. Results Paroxysmal nocturnal hemoglobinuria-phenotype granulocytes were detected in nine patients with low grade myelodysplastic syndrome who showed clinicopathological features of bone marrow failure, similar to aplastic anemia. All paroxysmal nocturnal hemoglobinuria-positive cases demonstrated loss of the four glycosylphosphatidylinositol-anchored proteins, with CD16−CD66b− clones being larger than those of CD55−CD59− (p<0.05). Altered glycosylphosphatidylinositol-anchored protein expression secondary to granulocytic hypogranulation, immaturity, and/or immunophenotypic abnormalities was present in a substantial number of cases and diagnostically challenging. Conclusions These results show that routine screening for paroxysmal nocturnal hemoglobinuria clones in patients with an intrinsic bone marrow disease who show no clinical evidence of hemolysis has an appreciable yield in patients with low grade myelodysplastic syndromes. The recognition of diagnostic caveats and pitfalls associated with the underlying intrinsic bone marrow disease is essential in interpreting paroxysmal nocturnal

  18. Detection of paroxysmal nocturnal hemoglobinuria clones in patients with myelodysplastic syndromes and related bone marrow diseases, with emphasis on diagnostic pitfalls and caveats.

    PubMed

    Wang, Sa A; Pozdnyakova, Olga; Jorgensen, Jeffrey L; Medeiros, L Jeffrey; Stachurski, Dariusz; Anderson, Mary; Raza, Azra; Woda, Bruce A

    2009-01-01

    The presence of paroxysmal nocturnal hemoglobinuria clones in the setting of aplastic anemia or myelodysplastic syndrome has been shown to have prognostic and therapeutic implications. However, the status of paroxysmal nocturnal hemoglobinuria clones in various categories of myelodysplastic syndrome and in other bone marrow disorders is not well-studied. By using multiparameter flow cytometry immunophenotypic analysis with antibodies specific for four glycosylphosphatidylinositol-anchored proteins (CD55, CD59, CD16, CD66b) and performing an aerolysin lysis confirmatory test in representative cases, we assessed the paroxysmal nocturnal hemoglobinuria-phenotype granulocytes in 110 patients with myelodysplastic syndrome, 15 with myelodysplastic/myeloproliferative disease, 5 with idiopathic myelofibrosis and 6 with acute myeloid leukemia. Paroxysmal nocturnal hemoglobinuria-phenotype granulocytes were detected in nine patients with low grade myelodysplastic syndrome who showed clinicopathological features of bone marrow failure, similar to aplastic anemia. All paroxysmal nocturnal hemoglobinuria-positive cases demonstrated loss of the four glycosylphosphatidylinositol-anchored proteins, with CD16(-)CD66b(-) clones being larger than those of CD55(-)CD59(-) (p<0.05). Altered glycosylphosphatidylinositol-anchored protein expression secondary to granulocytic hypogranulation, immaturity, and/or immunophenotypic abnormalities was present in a substantial number of cases and diagnostically challenging. These results show that routine screening for paroxysmal nocturnal hemoglobinuria clones in patients with an intrinsic bone marrow disease who show no clinical evidence of hemolysis has an appreciable yield in patients with low grade myelodysplastic syndromes. The recognition of diagnostic caveats and pitfalls associated with the underlying intrinsic bone marrow disease is essential in interpreting paroxysmal nocturnal hemoglobinuria testing correctly. In our experience, the CD

  19. Use of eculizumab and plasma exchange in successful combined liver-kidney transplantation in a case of atypical HUS associated with complement factor H mutation.

    PubMed

    Tran, Ha; Chaudhuri, Abanti; Concepcion, Waldo; Grimm, Paul C

    2014-03-01

    Atypical hemolytic uremic syndrome (aHUS) evolves into end-stage renal failure in nearly half of affected patients and is associated with defective regulation of the alternative complement pathway. Patients with a complement factor H (CFH) mutation have a 30-100% risk of graft loss due to aHUS recurrence or graft thrombosis. Since CFH is produced predominantly by the liver, combined liver-kidney transplant is a curative treatment option. One major unexpected risk includes liver failure secondary to uncontrolled complement activation. We report a successful combined liver-kidney transplantation with perioperative plasma exchange and use of the humanized anti-C5 monoclonal antibody eculizumab. An 11-month-old female presented with oliguric renal failure after 3 weeks of flu-like symptoms in the absence of diarrhea. Following the identification of Escherichia coli 0157:H7 in her stool, she was discharged home on peritoneal dialysis with a diagnosis of Shiga toxin-associated HUS. Three months later, she developed severe anemia, thrombocytopenia, and neurological involvement. aHUS was diagnosed and confirmed, and genetic testing revealed a mutation in CFH SCR20. Once donor organs became available, she received preoperative plasma exchange followed by eculizumab infusion with intra-operative fresh frozen plasma prior to combined liver-kidney transplant. At 19 months post-transplant, she continues to have excellent allograft and liver function without signs of disease recurrence. Perioperative use of eculizumab in conjunction with plasma exchange during simultaneous liver-kidney transplant can be used to inhibit terminal complement activity, thereby optimizing successful transplantation by reducing the risk of graft thrombosis.

  20. Use of eculizumab in crescentic IgA nephropathy: proof of principle and conundrum?

    PubMed Central

    Ring, Troels; Pedersen, Birgitte Bang; Salkus, Giedrius; Goodship, Timothy H.J.

    2015-01-01

    IgA nephropathy (IgAN) is characterized by a variable clinical course and multifaceted pathophysiology. There is substantial evidence to suggest that complement activation plays a pivotal role in the pathogenesis of the disease. Therefore, complement inhibition using the humanized anti-C5 monoclonal antibody eculizumab could be a rational treatment. We report here a 16-year-old male with the vasculitic form of IgAN who failed to respond to aggressive conventional therapy including high-dose steroids, cyclophosphamide and plasma exchange and who was treated with four weekly doses of 900 mg eculizumab followed by a single dose of 1200 mg. He responded rapidly to this treatment and has had a stable creatinine around 150 µmol/L (1.67 mg/dL) for >6 months. However, proteinuria was unabated on maximal conventional anti-proteinuric treatment, and a repeat renal biopsy 11 months after presentation revealed severe chronic changes. We believe this case provides proof of principle that complement inhibition may be beneficial in IgAN but also that development of chronicity may be independent of complement. PMID:26413271

  1. Retinal vein occlusion and paroxysmal nocturnal hemoglobinuria.

    PubMed

    Sorigue, Marc; Juncà, Jordi; Orna, Elisa; Romanic, Nevena; Sarrate, Edurne; Castellvi, Jordi; Soler, Montse; Rodríguez-Hernandez, Ines; Feliu, Evarist; Ruiz, Susana

    2017-07-01

    Paroxysmal nocturnal hemoglobinuria (PNH) is a rare disorder associated with increased risk for thrombosis and reduced life expectancy. Retinal vein occlusion (RVO) is a frequent cause of vision loss but its relationship with PNH has not been studied systematically. Patients followed up for RVO in our ophthalmology department were screened for the presence of a PNH clone in peripheral blood by means of flow cytometry. The presence of other well-documented risk factors for RVO was also analyzed. In a series of 110 patients (54 males, median age of 67) we found no evidence of PNH. Most patients (97/110) had cardiovascular risk factors and/or hyperhomocysteinemia (67/110). Inherited thrombophilias were rare (three confirmed cases). Therefore, PNH does not appear to play a role in the development of RVO. However, this finding does not necessarily apply to young patients and/or those with no conventional risk factors for RVO, due to the low number of patients in these subgroups in our population.

  2. 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.

  3. 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.

  4. Antibody mediated rejection associated with complement factor h-related protein 3/1 deficiency successfully treated with eculizumab.

    PubMed

    Noone, D; Al-Matrafi, J; Tinckam, K; Zipfel, P F; Herzenberg, A M; Thorner, P S; Pluthero, F G; Kahr, W H A; Filler, G; Hebert, D; Harvey, E; Licht, C

    2012-09-01

    Antibody mediated rejection (AMR) activates the classical complement pathway and can be detrimental to graft survival. AMR can be accompanied by thrombotic microangiopathy (TMA). Eculizumab, a monoclonal C5 antibody prevents induction of the terminal complement cascade (TCC) and has recently emerged as a therapeutic option for AMR. We present a highly sensitized 13-year-old female with end-stage kidney disease secondary to spina bifida-associated reflux nephropathy, who developed severe steroid-, ATG- and plasmapheresis-resistant AMR with TMA 1 week post second kidney transplant despite previous desensitization therapy with immunoglobulin infusions. Eculizumab rescue therapy resulted in a dramatic improvement in biochemical (C3; creatinine) and hematological (platelets) parameters within 6 days. The patient was proven to be deficient in complement Factor H-related protein 3/1 (CFHR3/1), a plasma protein that regulates the complement cascade at the level of C5 conversion and has been involved in the pathogenesis of atypical hemolytic uremic syndrome caused by CFH autoantibodies (DEAP-HUS). CFHR1 deficiency may have worsened the severe clinical progression of AMR and possibly contributed to the development of donor-specific antibodies. Thus, screening for CFHR3/1 deficiency should be considered in patients with severe AMR associated with TMA. © Copyright 2012 The American Society of Transplantation and the American Society of Transplant Surgeons.

  5. Outcomes of allogeneic stem cell transplantation in patients with paroxysmal nocturnal hemoglobinuria with or without aplastic anemia.

    PubMed

    Lee, Sung-Eun; Park, Sung Soo; Jeon, Young-Woo; Yoon, Jae-Ho; Cho, Byung-Sik; Eom, Ki-Sung; Kim, Yoo-Jin; Lee, Seok; Min, Chang-Ki; Kim, Hee-Je; Cho, Seok-Goo; Kim, Dong-Wook; Min, Woo-Sung; Lee, Jong Wook

    2017-10-01

    The aim of this study was to evaluate the long-term outcomes of allogeneic stem cell transplantation (SCT) in patients with paroxysmal nocturnal hemoglobinuria (PNH) with or without aplastic anemia (AA). A total of 33 patients with PNH clones who underwent allogeneic SCT were analyzed. After a median follow-up of 57 months (range, 6.0-151.3), the 5-year estimated overall survival rate was 87.9±5.7%. Four patients died of transplant-related mortality (TRM). With the exception of one patient with early TRM, 32 patients were engrafted. Two patients who had developed delayed GF received a second transplant and recovered. The cumulative incidences of acute graft-vs-host disease (GVHD) (≥grade II) and chronic GVHD (≥moderate) were 27.3±7.9% and 18.7±7.0%, respectively. Twenty-one patients receiving SCT with reduced-intensity conditioning (RIC) had available follow-up data for PNH cell population for the first 6 months post-transplant. Analysis of these data revealed that the PNH clones disappeared within approximately 2 months. RIC regimen was sufficient to eradicate PNH clones with sustained donor-type engraftment after allogeneic SCT. Therefore, application of allogeneic SCT with RIC should be considered in patients with PNH, in accordance with the severity of the underlying bone marrow failure. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  6. Evolutionary dynamics of paroxysmal nocturnal hemoglobinuria.

    PubMed

    Mon Père, Nathaniel; Lenaerts, Tom; Pacheco, Jorge M; Dingli, David

    2018-06-01

    Paroxysmal nocturnal hemoglobinuria (PNH) is an acquired clonal blood disorder characterized by hemolysis and a high risk of thrombosis, that is due to a deficiency in several cell surface proteins that prevent complement activation. Its origin has been traced to a somatic mutation in the PIG-A gene within hematopoietic stem cells (HSC). However, to date the question of how this mutant clone expands in size to contribute significantly to hematopoiesis remains under debate. One hypothesis posits the existence of a selective advantage of PIG-A mutated cells due to an immune mediated attack on normal HSC, but the evidence supporting this hypothesis is inconclusive. An alternative (and simpler) explanation attributes clonal expansion to neutral drift, in which case selection neither favours nor inhibits expansion of PIG-A mutated HSC. Here we examine the implications of the neutral drift model by numerically evolving a Markov chain for the probabilities of all possible outcomes, and investigate the possible occurrence and evolution, within this framework, of multiple independently arising clones within the HSC pool. Predictions of the model agree well with the known incidence of the disease and average age at diagnosis. Notwithstanding the slight difference in clonal expansion rates between our results and those reported in the literature, our model results lead to a relative stability of clone size when averaging multiple cases, in accord with what has been observed in human trials. The probability of a patient harbouring a second clone in the HSC pool was found to be extremely low ([Formula: see text]). Thus our results suggest that in clinical cases of PNH where two independent clones of mutant cells are observed, only one of those is likely to have originated in the HSC pool.

  7. Eculizumab treatment in severe pediatric STEC-HUS: a multicenter retrospective study.

    PubMed

    Percheron, Lucas; Gramada, Raluca; Tellier, Stéphanie; Salomon, Remi; Harambat, Jérôme; Llanas, Brigitte; Fila, Marc; Allain-Launay, Emma; Lapeyraque, Anne-Laure; Leroy, Valerie; Adra, Anne-Laure; Bérard, Etienne; Bourdat-Michel, Guylhène; Chehade, Hassid; Eckart, Philippe; Merieau, Elodie; Piètrement, Christine; Sellier-Leclerc, Anne-Laure; Frémeaux-Bacchi, Véronique; Dimeglio, Chloe; Garnier, Arnaud

    2018-03-23

    Hemolytic uremic syndrome related to Shiga-toxin-secreting Escherichia coli infection (STEC-HUS) remains a common cause of acute kidney injury in young children. No specific treatment has been validated for this severe disease. Recently, experimental studies highlight the potential role of complement in STEC-HUS pathophysiology. Eculizumab (EC), a monoclonal antibody against terminal complement complex, has been used in severe STEC-HUS patients, mostly during the 2011 German outbreak, with conflicting results. On behalf of the French Society of Pediatric Nephrology, we retrospectively studied 33 children from 15 centers treated with EC for severe STEC-HUS. Indication for EC was neurologic involvement in 20 patients, cardiac and neurologic involvement in 8, cardiac involvement in 2, and digestive involvement in 3. Based on medical status at last follow-up, patients were divided into two groups: favorable (n = 15) and unfavorable outcomes (n = 18). Among patients with favorable outcome, 11/14 patients (79%) displayed persistent blockade of complement activity before each EC reinjection. Conversely, in patients with unfavorable outcome, only 9/15 (53%) had persistent blockade (p = n.s.). Among 28 patients presenting neurological symptoms, 19 had favorable neurological outcome including 17 with prompt recovery following first EC injection. Only two adverse effects potentially related to EC treatment were reported. Taken together, these results may support EC use in severe STEC-HUS patients, especially those presenting severe neurological symptoms. The study, however, is limited by absence of a control group and use of multiple therapeutic interventions in treatment groups. Thus, prospective, controlled trials should be undertaken.

  8. High-dose Carboplatin/Etoposide/Melphalan increases risk of thrombotic microangiopathy and organ injury after autologous stem cell transplantation in patients with neuroblastoma.

    PubMed

    Jodele, Sonata; Dandoy, Christopher E; Myers, Kasiani; Wallace, Gregory; Lane, Adam; Teusink-Cross, Ashley; Weiss, Brian; Davies, Stella M

    2018-04-19

    Transplant-associated thrombotic microangiopathy (TA-TMA) is an increasingly recognized complication of hematopoietic cell transplant that can result in multi-organ failure (MOF). Patients undergoing high-dose chemotherapy with autologous stem cell transplant (aHCT) for neuroblastoma require good organ function to receive post-transplant radiation and immunotherapy. We examined TA-TMA incidence and transplant outcomes in patients with neuroblastoma receiving different transplant preparative regimens. Sixty patients underwent aHCT using high-dose chemotherapy: 41 patients received carboplatin/etoposide/melphalan (CEM), 13 patients busulfan/melphalan (Bu/Mel) and six patients received tandem transplant (cyclophosphamide/thiotepa and CEM). TA-TMA with MOF was diagnosed in 13 patients (21.7%) at a median of 18 days after aHCT. TA-TMA occurred in 12 patients receiving CEM and in 1 after cyclophosphamide/thiotepa. There were no incidences of TA-TMA after Bu/Mel regimen. Six of 13 patients with TA-TMA and MOF received terminal complement blocker eculizumab for therapy. They all recovered organ function and received planned post-transplant therapy. Out of seven patients who did not get eculizumab, two died from TA-TMA complications and four progressed to ESRD. We conclude that the CEM regimen is associated with a high incidence of clinically significant TA-TMA after aHCT and eculizumab can be safe and effective treatment option to remediate TA-TMA associated MOF.

  9. 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.

  10. 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.

  11. Preservation of renal function in atypical hemolytic uremic syndrome by eculizumab: a case report.

    PubMed

    Giordano, Mario; Castellano, Giuseppe; Messina, Giovanni; Divella, Claretta; Bellantuono, Rosa; Puteo, Flora; Colella, Vincenzo; Depalo, Tommaso; Gesualdo, Loreto

    2012-11-01

    Genetic mutations in complement components are associated with the development of atypical hemolytic uremic syndrome (aHUS), a rare disease with high morbidity rate triggered by infections or unidentified factors. The uncontrolled activation of the alternative pathway of complement results in systemic endothelial damage leading to progressive development of renal failure. A previously healthy 8-month-old boy was referred to our hospital because of onset of fever, vomiting, and a single episode of nonbloody diarrhea. Acute kidney injury with preserved diuresis, hemolytic anemia, and thrombocytopenia were detected, and common protocols for management of HUS were followed without considerable improvement. The persistent low levels of complement component C3 led us to hypothesize the occurrence of aHUS. In fact, the child carried a specific mutation in complement factor H (Cfh; nonsense mutation in 3514G>T, serum levels of Cfh 138 mg/L, normal range 350-750). Given the lack of response to therapy and the occurrence of kidney failure requiring dialysis, we used eculizumab as rescue therapy, a monoclonal humanized antibody against the complement component C5. One week from the first administration, we observed a significant improvement of all clinical and laboratory parameters with complete recovery from hemodialysis, even in the presence of systemic infections. Our case report shows that complement inhibiting treatment allows the preservation of renal function and avoids disease relapses during systemic infections.

  12. Frequency of and reasons for paroxysmal nocturnal haemoglobinuria screening in patients with unexplained anaemia.

    PubMed

    England, James T; Dalal, Bakul; Leitch, Heather A

    2018-04-01

    Referral to hematology for anemia is common. In paroxysmal nocturnal hemoglobinuria (PNH), cells deficient in the glycosylphosphatidyl inositol (GPI) anchor are lysed by complement. Eculizumab improves overall survival and quality of life while reducing hemolysis, transfusion requirements, and thrombosis. We evaluated the frequency of screening for PNH in patients with unexplained anemia. Key clinical features, laboratory data, and investigations were recorded for patients referred for anemia since 2010, without a specific cause found. PNH testing was done by flow cytometry. 540 patients had: anemia not yet diagnosed (NYD, n=318 (including unexplained iron deficiency, n=92; DAT-negative hemolysis, n=9)); anemia of chronic disease, n=173; and pancytopenia NYD, n=49. 82.4% had LDH testing done; 85.0% total bilirubin; 78.7% reticulocyte counts; and 40.6% haptoglobin level; 131 (24.2%) had possible hemolysis. PNH testing was done in 56 (10.4%). Those screened for PNH were more likely to have: younger age (P=0.04); a history of thrombosis (P<0.001); undergone a BMBx (P<0.001); received RBC transfusions (P=0.0018); or evidence of DAT-negative hemolysis (P<0.001). In summary, PNH was tested for in a minority of patients with unexplained anemia (10.4%) despite potential indicators of hemolysis in 24.2%. Increased screening could identify patients who would benefit from treatment and should be considered. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  13. [Evolution of paroxysmal nocturnal hemoglobinuria clone during an hemolytic crisis in a patient with aplastic anemia. Flow cytometry study].

    PubMed

    Canalejo, K; Galassi, N; Riera, N; Bengió, R; Aixalá, M

    2001-01-01

    The expansion of paroxysmal nocturnal hemoglobinuria (PHN) clone was evaluated in a patient with aplastic anemia (AA) of 18 years of evolution during an hemolytic crisis. On day 0, Ham and Sucrosa tests were positive and hematological parameters were altered. Low hemoglobin (Hb) levels and erythrocyte and leukocyte counts were found and continued decreasing on days 7 and 24 (last day of study). High LDH levels, indirect bilirubin and reticulocyte counts were detected throughout. We evaluated CD55 and CD59 on erythrocytes by flow cytometry. Our results showed low CD55 expression with respect to the normal pattern. Since day 0, CD59 staining detected two red cell populations: PNH I (48%), cells with positive fluorescence similar to normal and PNH III (52%), negative cells (PNH clone). These negative cells increased, reaching 70% on day 24. Other membrane anchored leukocyte proteins were also absent (CD14) or decreased (CD16). We found a good correlation between clinical observations, evolution of the laboratory values and expansion of the PNH clone.

  14. 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.

  15. Factor H autoantibody is associated with atypical hemolytic uremic syndrome in children in the United Kingdom and Ireland.

    PubMed

    Brocklebank, Vicky; Johnson, Sally; Sheerin, Thomas P; Marks, Stephen D; Gilbert, Rodney D; Tyerman, Kay; Kinoshita, Meredith; Awan, Atif; Kaur, Amrit; Webb, Nicholas; Hegde, Shivaram; Finlay, Eric; Fitzpatrick, Maggie; Walsh, Patrick R; Wong, Edwin K S; Booth, Caroline; Kerecuk, Larissa; Salama, Alan D; Almond, Mike; Inward, Carol; Goodship, Timothy H; Sheerin, Neil S; Marchbank, Kevin J; Kavanagh, David

    2017-11-01

    Factor H autoantibodies can impair complement regulation, resulting in atypical hemolytic uremic syndrome, predominantly in childhood. There are no trials investigating treatment, and clinical practice is only informed by retrospective cohort analysis. Here we examined 175 children presenting with atypical hemolytic uremic syndrome in the United Kingdom and Ireland for factor H autoantibodies that included 17 children with titers above the international standard. Of the 17, seven had a concomitant rare genetic variant in a gene encoding a complement pathway component or regulator. Two children received supportive treatment; both developed established renal failure. Plasma exchange was associated with a poor rate of renal recovery in seven of 11 treated. Six patients treated with eculizumab recovered renal function. Contrary to global practice, immunosuppressive therapy to prevent relapse in plasma exchange-treated patients was not adopted due to concerns over treatment-associated complications. Without immunosuppression, the relapse rate was high (five of seven). However, reintroduction of treatment resulted in recovery of renal function. All patients treated with eculizumab achieved sustained remission. Five patients received renal transplants without specific factor H autoantibody-targeted treatment with recurrence in one who also had a functionally significant CFI mutation. Thus, our current practice is to initiate eculizumab therapy for treatment of factor H autoantibody-mediated atypical hemolytic uremic syndrome rather than plasma exchange with or without immunosuppression. Based on this retrospective analysis we see no suggestion of inferior treatment, albeit the strength of our conclusions is limited by the small sample size. Copyright © 2017 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.

  16. ESCMID Study Group for Infections in Compromised Hosts (ESGICH) Consensus Document on the safety of targeted and biological therapies: an infectious diseases perspective (Soluble immune effector molecules [II]: agents targeting interleukins, immunoglobulins and complement factors).

    PubMed

    Winthrop, K L; Mariette, X; Silva, J T; Benamu, E; Calabrese, L H; Dumusc, A; Smolen, J S; Aguado, J M; Fernández-Ruiz, M

    2018-06-01

    The present review is part of the ESCMID Study Group for Infections in Compromised Hosts (ESGICH) Consensus Document on the safety of targeted and biological therapies. To review, from an Infectious Diseases perspective, the safety profile of agents targeting interleukins, immunoglobulins and complement factors and to suggest preventive recommendations. Computer-based MEDLINE searches with MeSH terms pertaining to each agent or therapeutic family. Patients receiving interleukin-1 (IL-1) -targeted (anakinra, canakinumab or rilonacept) or IL-5-targeted (mepolizumab) agents have a moderate risk of infection and no specific prevention strategies are recommended. The use of IL-6/IL-6 receptor-targeted agents (tocilizumab and siltuximab) is associated with a risk increase similar to that observed with anti-tumour necrosis factor-α agents. IL-12/23-targeted agents (ustekinumab) do not seem to pose a meaningful risk of infection, although screening for latent tuberculosis infection may be considered and antiviral prophylaxis should be given to hepatitis B surface antigen-positive patients. Therapy with IL-17-targeted agents (secukinumab, brodalumab and ixekizumab) may result in the development of mild-to-moderate mucocutaneous candidiasis. Pre-treatment screening for Strongyloides stercoralis and other geohelminths should be considered in patients who come from areas where these are endemic who are receiving IgE-targeted agents (omalizumab). C5-targeted agents (eculizumab) are associated with a markedly increased risk of infection due to encapsulated bacteria, particularly Neisseria spp. Meningococcal vaccination and chemoprophylaxis must be administered 2-4 weeks before initiating eculizumab. Patients with high-risk behaviours and their partners should also be screened for gonococcal infection. Preventive strategies are particularly encouraged to minimize the occurrence of neisserial infection associated with eculizumab. Copyright © 2018 European Society of Clinical

  17. Paroxysmal nocturnal hemoglobinuria first described in 1882 by Paul Strübing: an example of cooperation between clinical and basic research.

    PubMed

    Wilmanns, J C

    1982-12-01

    The 100th anniversary of the first description of paroxysmal nocturnal hemoglobinuria by Paul Strübing presents an opportunity to analyze the premises valid for the description of this disease in addition to an attempt at an extensive pathophysiological analysis. Strübing's two papers of 1882 were way ahead of his time, when pathophysiology was just at its beginning, particularly considering the fact that neither Marchiafava, who is still commonly credited wit the first description of this disease (1911) and its recognition as a clinical entity (1928), nor his student Micheli analyzed the PNH syndrome in pathophysiological terms as carefully as Strübing. Both of the former names were given to the disease, which is generally referred to as the Marchiafava-Micheli Anemia. William Crosby, who in 1951 in a historical review of PHN first pointed out the pioneering achievement of Strübing, suggested that it was mainly due to the lack of the right "intellectual climate" at the time that so little attention was paid to his work. Still another important aspect of the early history of PNH will be described in the present paper. The analysis of Strübing's publications leads to the conclusion that he was only able to make his important contribution to medical science because he not only had the appropriate clinical setting but also the scientific backup of the famous physiologist Leonhard Landois and his institute at the University of Greifswald, which is an excellent example of scientific progress through cooperation between a clinician and a research scientist.

  18. Atypical Hemolytic Uremic Syndrome: A Meta-Analysis of Case Reports Confirms the Prevalence of Genetic Mutations and the Shift of Treatment Regimens.

    PubMed

    Krishnappa, Vinod; Gupta, Mohit; Elrifai, Mohamed; Moftakhar, Bahar; Ensley, Michael J; Vachharajani, Tushar J; Sethi, Sidharth Kumar; Raina, Rupesh

    2018-04-01

    Atypical hemolytic uremic syndrome (aHUS) is a rare life-threatening thrombotic microangiopathy (TMA) affecting multiple organ systems. Recently, aHUS has been shown to be associated with uncontrolled complement activation due to mutations in the alternative pathway of complement components paving the way for targeted drug therapy. By meta-analysis of case reports, we discuss the impact of new treatment strategies on the resolution time of aHUS symptoms and mortality, and the distribution of genetic mutations. A PubMed/Medline search was conducted for "atypical hemolytic uremic syndrome" case reports published between November 2005 and November 2015. R Version 3.2.2 was used to calculate descriptive statistics and perform univariate analyses. Wilcoxon rank-sum test was used to compare time to symptoms resolution, creatinine and platelet count normalization across the treatment and mutation carrier groups. A total of 259 aHUS patients were reported in 176 articles between 2005 and 2015. In the last 5-year period compared to the precedent, there was an increase in the number of aHUS cases reported (180 vs. 79 cases) and the use of eculizumab also increased (6.3% to 46.1%, P < 0.000), although plasma exchange usage did not change (P = 0.281). CFH antibodies were present in a significantly higher number of patients treated with plasma exchange therapy (19.1%, P = 0.000) while none of the non-plasma exchange therapy group had CFH antibodies. Most common mutation was CFH (50%, 69/139) followed by CFHR1 (35%, 30/85), MCP (22.8%, 23/101) and CFI (16.6%, 17/102). Time to symptoms resolution and serum creatinine or platelet count normalization were not significantly different between eculizumab and non-eculizumab group (P = 0.166, P = 0.361, P = 0.834), and between plasma exchange and non-plasma exchange group (P = 0.150, P = 0.135, P = 0.784). However, both eculizumab and plasma exchange groups had early platelet recovery (22 vs. 30

  19. [Ex vivo expansion and clonal variation of CD34(+)CD59(+) cells from bone marrow in children with paroxysmal nocturnal hemoglobinuria].

    PubMed

    Xiao, Juan; Wu, Yong-Ji; Han, Bing; Dong, Hong-Yan; Chen, Shi-Ping

    2013-08-01

    To investigate the isolation, purification and ex vivo expansion of CD34(+)CD59(+) cells from the bone marrow of children with paroxysmal nocturnal hemoglobinuria (PNH), to evaluate the capability of long-term hematopoietic reconstruction of the expanded CD34(+)CD59(+) cells, and to provide a laboratory basis for novel treatment of PNH. CD34(+)CD59(+) cells were isolated from the bone marrow mononuclear cells of children with PNH using immunomagnetic beads and flow cytometer in sequence. The isolated cells were subjected to ex vivo expansion in the presence of different combinations of hematopoietic growth factors for two weeks. The colony-forming cells and long-term culture-initiating cells (LTC-ICs) were cultured and counted. The optimal combination of hematopoietic growth factors for ex vivo expansion was stem cell factor+interleukin (IL)-3+IL-6+FLT3 ligand+thrombopoietin+ery-thropoietin, and maximum expansion (30.4 ± 6.7 folds) was seen on day 7 of days 4 to 14 of ex vivo expansion. After ex vivo expansion, CD34(+)CD59(+) cells remained CD59-positive, retained strong capability of forming colony-forming units, and could still form LTC-ICs. There was no significant difference in capability of forming LTC-ICs between CD34(+)CD59(+) cells before and after expansion. The expansion capability of CD34(+)CD59(+) cells from children with PNH was significantly lower than that of CD34(+) cells from normal controls (P<0.01). The CD34(+)CD59(+) cells from children with PNH can be expanded in vitro. Post-expansion CD34(+)CD59(+) cells retain capability of long-term hematopoietic reconstruction. CD34(+)CD59(+) cells showed no trend towards PNH clone during culture. Ex vivo expansion of CD34(+)CD59(+) cells from children with PNH might be practical in performing autologous transplantation clinically for these children.

  20. Paroxysmal Nocturnal Hemoglobinuria is rare cause for thrombosis of the intra-abdominal veins in the ethnic Indian population - results from FLAER-based flowcytometry screening.

    PubMed

    Ahluwalia, Jasmina; Naseem, Shano; Sachdeva, Man Updesh Singh; Bose, Parveen; Bose, Sunil Kumar; Kumar, Narender; Thapa, Babu Ram; Varma, Neelam; Chawla, Yogesh Kumar

    2014-01-01

    Paroxysmal nocturnal hemoglobinuria (PNH) may present as cytopenia, hemolysis, or thrombosis at unusual sites including splanchnic vessels. Thrombosis of the portal veins and hepatic veins are associated with thrombophilic risk factors: deficiencies of protein C, protein S, and antithrombin, positivity for antiphospholipid antibodies, and factor V Leiden mutation. There is limited information regarding PNH presenting primarily as a thrombotic event. We prospectively screened 142 consecutive patients with intrabdominal thrombosis and 106 controls with fluorescently labeled inactive toxin aerolysin (FLAER)-based flowcytometry to assess the frequency of PNH as a thrombophilic risk factor in patients with intra-abdominal thrombosis. Granulocytes of patients and controls were screened with CD 24 and FLAER and monocytes with CD 14 and FLAER. Dual negativity of >1% events in both lineages was interpreted as a positive PNH clone. Screening for thrombophilia risk factors was carried out. Two (1.4%) cases had large PNH clones. RBC also demonstrated the PNH defect. Thrombophilia risk factors were as follows: deficiency of protein S, protein C, and antithrombin in 13.4%, 4.9%, and 2.1%, respectively, and positivity for anti-beta-2 glycoprotein 1, anticardiolipin antibodies, and lupus anticoagulant in 9.2%, 1.4%, and 0.7%, respectively. Factor V Leiden mutation was seen in 1.4% patients. PNH was uncommon in patients with intra-abdominal thrombosis in the ethnic Indian population. Despite low positivity, screening by flowcytometry for PNH is of value in this group of patients because it provides an opportunity to rapidly establish the diagnosis of this treatable disorder, which might otherwise be missed if the initial presentation is only thrombotic. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  1. Glucose-6-Phosphate Dehydrogenase Deficiency Mimicking Atypical Hemolytic Uremic Syndrome.

    PubMed

    Walsh, Patrick R; Johnson, Sally; Brocklebank, Vicky; Salvatore, Jacobo; Christian, Martin; Kavanagh, David

    2018-02-01

    A 4-year-old boy presented with nonimmune hemolysis, thrombocytopenia, and acute kidney injury. Investigations for an underlying cause failed to identify a definitive cause and a putative diagnosis of complement-mediated atypical hemolytic uremic syndrome (aHUS) was made. The patient was started initially on plasma exchange and subsequently eculizumab therapy, after which his kidney function rapidly improved. While on eculizumab therapy, despite adequate complement blockade, he presented 2 more times with hemolytic anemia and thrombocytopenia, but without renal involvement. Genetic analysis did not uncover a mutation in any known aHUS gene (CFH, CFI, CFB, C3, CD46, THBD, INF2, and DGKE) and anti-factor H antibodies were undetectable. Whole-exome sequencing was undertaken to identify a cause for the eculizumab resistance. This revealed a pathogenic variant in G6PD (glucose-6-phosphate dehydrogenase), which was confirmed by functional analysis demonstrating decreased erythrocyte G6PD activity. Eculizumab therapy was withdrawn. Complement-mediated aHUS is a diagnosis of exclusion and this case highlights the diagnostic difficulty that remains without an immediately available biomarker for confirmation. This case of G6PD deficiency presented with a phenotype clinically indistinguishable from complement-mediated aHUS. We recommend that G6PD deficiency be included in the differential diagnosis of patients presenting with aHUS and suggest measuring erythrocyte G6PD concentrations in these patients. Copyright © 2017. Published by Elsevier Inc.

  2. 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.

  3. Factors Predicting Risk for Antibody-mediated Rejection and Graft Loss in Highly Human Leukocyte Antigen Sensitized Patients Transplanted After Desensitization.

    PubMed

    Vo, Ashley A; Sinha, Aditi; Haas, Mark; Choi, Jua; Mirocha, James; Kahwaji, Joseph; Peng, Alice; Villicana, Rafael; Jordan, Stanley C

    2015-07-01

    Desensitization with intravenous immunoglobulin and rituximab (I+R) significantly improves transplant rates in highly sensitized patients, but antibody-mediated rejection (ABMR) remains a concern. Between July 2006 and December 2012, 226 highly sensitized patients received transplants after desensitization. Most received alemtuzumab induction and standard immunosuppression. Two groups were examined: ABMR (n = 181) and ABMR (n = 45, 20%). Risk factors for ABMR, pathology, and outcomes were assessed. Significant risks for ABMR included previous transplants and pregnancies as sensitizing events, donor-specific antibody (DSA) relative intensity scores greater than 17, presence of both class I and II DSAs at transplant and time on waitlist. The ABMR showed a significant benefit for graft survival and glomerular filtration rate at 5 years (P < 0.0001). Banff pathology characteristics for ABMR patients with or without graft loss did not differ. C4d versus C4d ABMR did not predict graft loss (P = 0.086). Thrombotic microangiopathy (TMA) significantly predicted graft failure (P = 0.045). The ABMR episodes were treated with I+R (n = 25), or, in more severe ABMR, plasma exchange (PLEX)+I+R (n = 20). Graft survival for patients treated with I+R was superior (P = 0.028). Increased mortality was seen in ABMR patients experiencing graft loss after ABMR treatment (P = 0.004). The PLEX + Eculizumab improved graft survival for TMA patients (P = 0.036). Patients desensitized with I+R who remain ABMR have long-term graft and patient survival. The ABMR patients have significantly reduced graft survival and glomerular filtration rate at 5 years, especially TMA. Severe ABMR episodes benefit from treatment with PLEX + Eculizumab. The DSA-relative intensity scores at transplant was a strong predictor of ABMR. Donor-specific antibody avoidance and reduction strategies before transplantation are critical to avoiding ABMR and improving long-term outcomes.

  4. Receivers

    NASA Technical Reports Server (NTRS)

    Donnelly, H.

    1983-01-01

    Before discussing Deep Space Network receivers, a brief description of the functions of receivers and how they interface with other elements of the Network is presented. Different types of receivers are used in the Network for various purposes. The principal receiver type is used for telemetry and tracking. This receiver provides the capability, with other elements of the Network, to track the space probe utilizing Doppler and range measurements, and to receive telemetry, including both scientific data from the onboard experiments and engineering data pertaining to the health of the probe. Another type of receiver is used for radio science applications. This receiver measures phase perturbations on the carrier signal to obtain information on the composition of solar and planetary atmospheres and interplanetary space. A third type of receiver utilizes very long baseline interferometry (VLBI) techniques for both radio science and spacecraft navigation data. Only the telemetry receiver is described in detail in this document. The integration of the Receiver-Exciter subsystem with other portions of the Deep Space Network is described.

  5. Increased Expression of Complement Regulators CD55 and CD59 on Peripheral Blood Cells in Patients with EAHEC O104:H4 Infection

    PubMed Central

    Ullrich, Sebastian; Fraedrich, Katharina; Schulze zur Wiesch, Julian; Fründt, Thorben; Tiegs, Gisa; Lohse, Ansgar; Lüth, Stefan

    2013-01-01

    Background An outbreak of Shiga Toxin 2 (Stx-2) producing enterohemorrhagic and enteroaggregative E.coli (EAHEC) O104H4 infection in May 2011 caused enterocolitis and an unprecedented high 22% rate of hemolytic uremic syndrome (HUS). The monoclonal anti-C5 antibody Eculizumab (ECU) has been used experimentally in EAHEC patients with HUS but treatment efficacy is uncertain. ECU can effectively prevent hemolysis in paroxysmal nocturnal hemoglobinuria (PNH) caused by a lack of complement-regulating CD55 and CD59 on blood cells. We hypothesized a low expression of CD55 and CD59, as seen in PNH, might correlate with HUS development in EAHEC patients. Methods 76 EAHEC patients (34 only gastrointestinal symptoms [GI], 23: HUS, 19: HUS and neurological symptoms [HUS/N]) and 12 healthy controls (HC) were tested for the expression of CD55 and CD59 on erythrocytes and leukocytes retrospectively. Additionally, the effect of Stx-2 on CD55 and CD59 expression on erythrocytes and leukocytes was studied ex vivo. Results CD55 expression on erythrocytes was similar in all patient groups and HC while CD59 showed a significantly higher expression in HUS and HUS/N patients compared to HC and the GI group. CD55 and CD59 expression on leukocytes and their subsets was significantly higher in all patient groups compared to HC regardless of treatment type. However, CD59 expression on erythrocytes was significantly higher in HUS and HUS/N patients treated combined with plasma separation (PS) and ECU compared to HC. Adding Stx-2 ex vivo had no effect on CD55 and CD59 expression on leukocytes from HC or patients. Conclusion HUS evolved independently from CD55 and CD59 expression on peripheral blood cells in EAHEC O104:H4 infected patients. Our data do not support a role for CD55 and CD59 in HUS development during EAHEC O104:H4 infection and point to a different mechanism within the complement system for HUS development in EAHEC patients. PMID:24086391

  6. Stem Cell Transplantation as Immunotherapy for Hematologic Malignancies

    ClinicalTrials.gov

    2009-01-28

    Leukemia; Acute Lymphoblastic Leukemia; Acute Myeloid Leukemia; Chronic Myeloid Leukemia; Juvenile Myelomonocytic Leukemia; Myelodysplastic Syndrome; Paroxysmal Nocturnal Hemoglobinuria; Hodgkin's Lymphoma; Non-Hodgkin Lymphoma

  7. Paroxysmal nocturnal hemoglobinuria (PNH)

    MedlinePlus

    ... blood cells that are missing a gene called PIG-A. This gene allows a substance called glycosyl- ... to help certain proteins stick to cells. Without PIG-A, important proteins cannot connect to the cell ...

  8. Paroxysmal Nocturnal Hemoglobinuria (PNH)

    MedlinePlus

    ... break apart. Normal red blood cells have a shield of proteins that protect them from coming under ... own immune system. PNH occurs because that protein shield is missing. PNH is often associated with reduced ...

  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. Basiliximab #2: In-Vivo Activated T-Cell Depletion to Prevent Graft-Versus_Host Disease (GVHD) After Nonmyeloablative Allotransplantation for the Treatment of Blood Cancer

    ClinicalTrials.gov

    2016-01-28

    Acute Myelogenous Leukemia; Acute Lymphocytic Leukemia; Chronic Myelogenous Leukemia; Chronic Lymphocytic Leukemia; Myelodysplasia; Non-Hodgkin's Lymphoma; Hodgkin's Disease; Multiple Myeloma; Myelofibrosis; Anemia, Aplastic; Hemoglobinuria, Paroxysmal

  11. Hematopoietic Stem Cell Transplant for High Risk Hemoglobinopathies

    ClinicalTrials.gov

    2017-12-03

    Sickle Cell Disease; Transfusion Dependent Alpha- or Beta- Thalassemia; Diamond Blackfan Anemia; Paroxysmal Nocturnal Hemoglobinuria; Glanzmann Thrombasthenia; Severe Congenital Neutropenia; Shwachman-Diamond Syndrome; Non-Malignant Hematologic Disorders

  12. Haploidentical Stem Cell Transplantation for Patients With Hematologic Malignancies

    ClinicalTrials.gov

    2009-01-28

    Leukemia, Acute Lymphocytic (ALL); Leukemia, Myeloid, Acute(AML); Leukemia, Myeloid, Chronic(CML); Juvenile Myelomonocytic Leukemia(JMML); Hemoglobinuria, Paroxysmal Nocturnal (PNH); Lymphoma, Non-Hodgkin (NHL); Myelodysplastic Syndrome (MDS)

  13. Ham test

    MedlinePlus

    Acid hemolysin test; Paroxysmal nocturnal hemoglobinuria - Ham test; PNH - Ham test ... BJ. In: Chernecky CC, Berger BJ, eds. Laboratory Tests and Diagnostic Procedures . 6th ed. Philadelphia, PA: Elsevier ...

  14. Mismatched Family Member Donor Transplantation for Children and Young Adults With High Risk Hematological Malignancies

    ClinicalTrials.gov

    2018-05-09

    Leukemia, Acute Lymphocytic (ALL); Leukemia, Myeloid, Acute(AML); Leukemia, Myeloid, Chronic(CML); Juvenile Myelomonocytic Leukemia (JMML); Hemoglobinuria, Paroxysmal Nocturnal (PNH); Hodgkin Lymphoma; Lymphoma, Non-Hodgkin (NHL); Myelodysplastic Syndrome (MDS)

  15. Haploidentical Stem Cell Transplant for Treatment Refractory Hematological Malignancies

    ClinicalTrials.gov

    2009-02-12

    Acute Lymphoblastic Leukemia (ALL); Acute Myeloid Leukemia (AML); Secondary AML; Myelodysplastic Syndrome (MDS); Secondary MDS; Chronic Myeloid Leukemia; Juvenile Myelomonocytic Leukemia (JMML); Paroxysmal Nocturnal Hemoglobinuria (PNH); Lymphoma, Non-Hodgkin; Hodgkin Disease

  16. 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.

  17. 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.

  18. CALUTRON RECEIVERS

    DOEpatents

    Lofgren, E.J.

    1958-09-01

    Improvements are described in isotope separation devices of the calutron type and, in particular, deals with a novel caiutron receiver which passes the optimum portions of the ion beam to a collecting chamber. In broad aspects the receiver provides means for pass delimited pontion of the beam and an elongated collecting pocket disposed to receive ions passed by the beam delimiting means. The collecting pocket is transversely partitioned into a plurality of ion receiving compartments respectively defined by a corresponding plurality of separately removable liner elements.

  19. 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.

  20. Unrelated Donor Stem Cell Transplantation

    ClinicalTrials.gov

    2013-12-05

    Severe Aplastic Anemia; Paroxysmal Nocturnal Hemoglobinuria; Acute Myelogenous Leukemia; Acute Lymphoblastic Leukemia; Myelodysplastic Syndromes; Myeloproliferative Syndromes; Chronic Myelogenous Leukemia; Hodgkin's Lymphoma; Non-Hodgkin's Lymphoma; Multiple Myeloma; Chronic Lymphocytic Leukemia; Small Lymphocytic Lymphoma; Large Granulocytic Leukemia

  1. Data-fusion receiver

    DOEpatents

    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".

  2. Nonmyeloablative Allogeneic Transplant

    ClinicalTrials.gov

    2013-12-05

    Aplastic Anemia; Paroxysmal Nocturnal Hemoglobinuria; Acute Myelogenous Leukemia; Acute Lymphocytic Leukemia; Myelodysplastic Syndrome; Chronic Myelogenous Leukemia; Chronic Lymphocytic Leukemia; Hodgkin's Lymphoma; Non-Hodgkin's Lymphoma; Mantle Cell Lymphoma; Multiple Myeloma; Waldenstrom Macroglobulinemia; Breast Cancer; Renal Cell Carcinoma; Melanoma; Sarcoma; Ovarian Cancer; Thymoma

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. Receiver Test Selection Criteria

    DOT National Transportation Integrated Search

    2015-03-12

    The DOT requests that GPS manufacturers submit receivers for test in the following TWG categories: - Aviation (non-certified), cellular, general location/navigation, high precision, timing, networks, and space-based receivers - Each receiver should b...

  11. Genetics Home Reference: paroxysmal nocturnal hemoglobinuria

    MedlinePlus

    ... at increased risk of developing cancer in blood-forming cells (leukemia). In some cases, people who have ... mutations of the PIGA gene occur in blood-forming cells called hematopoietic stem cells, which are found ...

  12. 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.

  13. Optical superheterodyne receiver.

    PubMed

    Lucy, R F; Lang, K; Peters, C J; Duval, K

    1967-08-01

    Optical communications experiments at 6328 A, comparing the fading characteristics of coherent and noncoherent optical detection, have been performed over a 1-km real atmospheric path in different weather conditions. The results show that fading is less severe for noncoherent detection and that the fading characteristic for both types vary significantly with weather conditions. In addition, the similarity of optical FM to rf FM is demonstrated. The measurements were performed using a remote laser transmitter and an optical superheterodyne receiver operating simultaneously in both a coherent and noncoherent detection mode. The receiver, tunable over a frequency range of 1 GHz at the IF difference frequency of 30 MHz, has automatic frequency control and also uses a precision angle tracking servo to maintain receiver spatial alignment with a remote transmitter. The angle and frequency tracking capability permit operation between moving transmitter and receiver terminals.

  14. Advanced space solar dynamic receivers

    NASA Technical Reports Server (NTRS)

    Strumpf, Hal J.; Coombs, Murray G.; Lacy, Dovie E.

    1988-01-01

    A study has been conducted to generate and evaluate advanced solar heat receiver concepts suitable for orbital application with Brayton and Stirling engine cycles in the 7-kW size range. The generated receiver designs have thermal storage capability (to enable power production during the substantial eclipse period which accompanies typical orbits) and are lighter and smaller than state-of-the-art systems, such as the Brayton solar receiver being designed and developed by AiResearch for the NASA Space Station. Two receiver concepts have been developed in detail: a packed bed receiver and a heat pipe receiver. The packed bed receiver is appropriate for a Brayton engine; the heat pipe receiver is applicable for either a Brayton or Stirling engine. The thermal storage for both concepts is provided by the melting and freezing of a salt. Both receiver concepts offer substantial improvements in size and weight compared to baseline receivers.

  15. Receiver For Solar Air Turbine

    NASA Technical Reports Server (NTRS)

    Kofal, A.; Shannon, R.; Zimmerman, D. K.

    1985-01-01

    Solar receiver heats air to temperature high enough to drive gas turbine. Receiver has thermal output of about 70 kilowatts. Pointing downward at focal position of solar reflector, proposed receiver accepts intense concentrated sunlight. Although temperatures in receiver may rise to 1,500 degrees F (816 degrees C) or more, calculations show receiver loses less than 10 percent of insolation by convection through aperture. Receiver designed for 30-year life without scheduled maintenance or replacement.

  16. [Gemcitabine-induced thrombotic microangiopathy: Can we improve screening and treatment?

    PubMed

    Charmetant, Xavier; Jolivot, Anne; Fournier, Thomas; Puthet, Jean-Charles; Cassier, Philippe; Lemoine, Sandrine; Juillard, Laurent

    2017-06-01

    Thrombotic microangiopathy is a rare but severe complication of treatment with gemcitabine. Its prevalence increases because gemcitabine's indications are growing. We report four cases, which presented with common clinical and biological manifestations, i.e. high blood pressure, proteinuria and increasing plasmatic creatinine level. However, severity was not similar, hemodialysis was inconstant. There is no consensus on treatment for this condition. Stopping gemcitabine is essential. Treatment was dispensed considering the severity of the presentation: plasma exchange therapy of variable outcome, and eculizumab, which was efficient when used. It's important to note that this syndrome includes common and frequent signs in patients receiving chemotherapies. But they must encourage the research of most specific signs, such as hypertension, mechanic hemolysis signs, proteinuria or hematuria, in order to recognize thrombotic microangiopathy as early as possible to treat it precociously, and to prevent additional gemcitabine injections. Copyright © 2017 Société francophone de néphrologie, dialyse et transplantation. Published by Elsevier Masson SAS. All rights reserved.

  17. 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.

  18. High temperature solar receiver

    NASA Technical Reports Server (NTRS)

    1981-01-01

    The development of a high temperature solar thermal receiver is described. A prototype receiver and associated test support (auxiliary) hardware was fabricated. Shakedown and initial performance tests of the prototype receiver were performed. Maximum outlet temperatures of 1600 F were achieved at 100% solar (70-75 kW) input power with 900 F inlet temperatures and a subsequent testing was concluded by a 2550 F outlet run. The window retaining assembly was modified to improve its tolerance for thermal distortion of the flanges. It is shown that cost effective receiver designs can be implemented within the framework of present materials technology.

  19. Progress in Desensitization of the Highly HLA Sensitized Patient.

    PubMed

    Jordan, S C; Choi, J; Kahwaji, J; Vo, A

    2016-04-01

    The presence of HLA antibodies remains a significant and often impenetrable barrier to kidney transplantation, leading to increased morbidity and mortality for patients remaining on long-term dialysis. In recent years, a number of new approaches have been developed to overcome these barriers. Intravenous immunoglobulin (IVIG) remains the lynchpin of HLA desensitization therapy and has been shown in a prospective, randomized, placebo-controlled trial to improve transplantation rates. In addition, IVIG used in low doses with plasma exchange is a reliable protocol for desensitization. Another significant advancement was the addition of rituximab (anti-B-cell therapy) to IVIG and plasma exchange-based desensitization. This approach has significantly improved rates of transplantation and outcomes. There is limited experience with bortezomib (anti-plasma cell therapy) and eculizumab (complement inhibition) for desensitization. However, recent data from a completed trial of eculizumab failed to show a significant benefit for prevention of antibody-mediated rejection compared with standard therapy plus placebo, and bortezomib produced inconsistent results. There is a growing interest in developing new therapeutic agents for desensitization. Newer approaches that address antibody reduction with B-cell depletion are discussed. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. 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.

  1. 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.

  2. 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.

  3. Airflow Assists Solar Receiver

    NASA Technical Reports Server (NTRS)

    Revere, W. R.; Laumann, E. A.

    1984-01-01

    Heat loss by convection reduced. Simplified solar receiver concept involves inwardly directed flow of cooling air and "air door" to reduce loss by convection. Receiver is constructed from inexpensive materials.

  4. Ceramics for Solar Receivers

    NASA Technical Reports Server (NTRS)

    Kudirka, A. A.

    1984-01-01

    Materials for high-temperature use reviewed. Report discusses characteristics of ceramics and assesses potential of candidate materials in solar receivers. Design requirements presented, including those for receiver with fluid exit temperatures up to 1,425 degrees C.

  5. Repetitive reddish discoloration of urine in a female adolescent following short-distance walking on a smooth road: Questions.

    PubMed

    Siomou, Ekaterini; Baziou, Maria; Premetis, Evagelos; Vercellati, Cristina; Chaliasos, Nikolaos; Makis, Alexandros

    2017-12-01

    A previously healthy 15-year-old girl was evaluated following five episodes of reddish urine discoloration after walking for approximately 30 min on a smooth roadway. In each episode, the discoloration lasted for four to five urinations and followed by normal urine dipstick tests. No other exercise-produced urine discoloration and no other symptoms were reported. Laboratory evaluation during the episodes revealed a reddish urine sample with 3+ hemoglobin/myoglobin and absence of hematuria. Full blood count, serum creatinine, liver function tests, and electrolyte levels were all within normal limits. Myoglobulinuria was excluded, since muscle enzymes were within normal limits. Blood smear analysis showed mild anisopoikilocytosis with stomatocytes and ovalocytes, leading to extended evaluation for erythrocyte disorders. This case is interesting in that the hemoglobinuria occurred after mild walking and was accompanied by erythrocyte morphological changes. This quiz discusses the differential diagnosis of hemoglobinuria with particular reference to the conditions of appearance (after walking) and emphasizes the importance of step-by-step investigations to reach a definitive diagnosis.

  6. 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.

  7. Real-time software receiver

    NASA Technical Reports Server (NTRS)

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

  8. Real-time software receiver

    NASA Technical Reports Server (NTRS)

    Psiaki, Mark L. (Inventor); Ledvina, Brent M. (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.

  9. Advanced solar receivers for space power

    NASA Technical Reports Server (NTRS)

    Strumpf, H. J.; Coombs, M. G.; Lacy, D. E.

    1988-01-01

    A study has been conducted to generate and evaluate advanced solar heat receiver concepts suitable for orbital application with Brayton and Stirling engine cycles in the 7-kW size range. The generated receiver designs have thermal storage capability and, when implemented, will be lighter, smaller, and/or more efficient than baseline systems such as the configuration used for the Brayton solar receiver under development by Garrett AiResearch for the NASA Space Station. In addition to the baseline designs, four other receiver concepts were designed and evaluated with respect to Brayton and Stirling engines. These concepts include a higher temperature version of the baseline receiver, a packed bed receiver, a plate-fin receiver, and a heat pipe receiver. The thermal storage for all designs is provided by the melting and freezing of a salt.

  10. 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.

  11. Numerical modeling of reflux solar receivers

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hogan, R.E. Jr.

    1993-05-01

    Using reflux solar receivers to collect solar energy for dish-Stirling electric power generation systems is presently being investigated by several organizations, including Sandia National Laboratories, Albuquerque, N. Mex. In support of this program, Sandia has developed two numerical models describing the thermal performance of pool-boiler and heat-pipe reflux receivers. Both models are applicable to axisymmetric geometries and they both consider the radiative and convective energy transfer within the receiver cavity, the conductive and convective energy transfer from the receiver housing, and the energy transfer to the receiver working fluid. The primary difference between the models is the level of detailmore » in modeling the heat conduction through the receiver walls. The more detailed model uses a two-dimensional finite control volume method, whereas the simpler model uses a one-dimensional thermal resistance approach. The numerical modeling concepts presented are applicable to conventional tube-type solar receivers, as well as to reflux receivers. Good agreement between the two models is demonstrated by comparing the predicted and measured performance of a pool-boiler reflux receiver being tested at Sandia. For design operating conditions, the receiver thermal efficiencies agree within 1 percent and the average receiver cavity temperature within 1.3 percent. The thermal efficiency and receiver temperatures predicted by the simpler thermal resistance model agree well with experimental data from on-sun tests of the Sandia reflux pool-boiler receiver. An analysis of these comparisons identifies several plausible explanations for the differences between the predicted results and the experimental data.« less

  12. Fludarabine Phosphate and Total Body Irradiation Followed by a Donor Peripheral Stem Cell Transplant in Treating Patients With Myelodysplastic Syndromes or Myeloproliferative Disorders

    ClinicalTrials.gov

    2018-03-28

    Atypical Chronic Myeloid Leukemia, BCR-ABL1 Negative; Chronic Myelomonocytic Leukemia; de Novo Myelodysplastic Syndrome; Essential Thrombocythemia; Myeloproliferative Neoplasm; Paroxysmal Nocturnal Hemoglobinuria; Polycythemia Vera; Polycythemia Vera, Post-Polycythemic Myelofibrosis Phase; Primary Myelofibrosis; Refractory Anemia; Refractory Anemia With Excess Blasts; Refractory Anemia With Ring Sideroblasts; Refractory Cytopenia With Multilineage Dysplasia; Refractory Cytopenia With Multilineage Dysplasia and Ring Sideroblasts

  13. Receiver function HV ratio: a new measurement for reducing non-uniqueness of receiver function waveform inversion

    NASA Astrophysics Data System (ADS)

    Chong, Jiajun; Chu, Risheng; Ni, Sidao; Meng, Qingjun; Guo, Aizhi

    2018-02-01

    It is known that a receiver function has relatively weak constraint on absolute seismic wave velocity, and that joint inversion of the receiver function with surface wave dispersion has been widely applied to reduce the trade-off of velocity with interface depth. However, some studies indicate that the receiver function itself is capable for determining the absolute shear-wave velocity. In this study, we propose to measure the receiver function HV ratio which takes advantage of the amplitude information of the receiver function to constrain the shear-wave velocity. Numerical analysis indicates that the receiver function HV ratio is sensitive to the average shear-wave velocity in the depth range it samples, and can help to reduce the non-uniqueness of receiver function waveform inversion. A joint inversion scheme has been developed, and both synthetic tests and real data application proved the feasibility of the joint inversion.

  14. 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.

  15. 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.

  16. 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.

  17. 47 CFR 15.121 - Scanning receivers and frequency converters used with scanning receivers.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... transmissions to analog voice audio. (2) Be designed so that the tuning, control and filtering circuitry is inaccessible. The design must be such that any attempts to modify the equipment to receive transmissions from... Radiotelephone Service transmissions. (e) Scanning receivers and frequency converters designed for use with...

  18. 47 CFR 15.121 - Scanning receivers and frequency converters used with scanning receivers.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... transmissions to analog voice audio. (2) Be designed so that the tuning, control and filtering circuitry is inaccessible. The design must be such that any attempts to modify the equipment to receive transmissions from... Radiotelephone Service transmissions. (e) Scanning receivers and frequency converters designed for use with...

  19. 47 CFR 15.121 - Scanning receivers and frequency converters used with scanning receivers.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... transmissions to analog voice audio. (2) Be designed so that the tuning, control and filtering circuitry is inaccessible. The design must be such that any attempts to modify the equipment to receive transmissions from... Radiotelephone Service transmissions. (e) Scanning receivers and frequency converters designed for use with...

  20. 47 CFR 15.121 - Scanning receivers and frequency converters used with scanning receivers.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... transmissions to analog voice audio. (2) Be designed so that the tuning, control and filtering circuitry is inaccessible. The design must be such that any attempts to modify the equipment to receive transmissions from... Radiotelephone Service transmissions. (e) Scanning receivers and frequency converters designed for use with...

  1. 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.

  2. 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.

  3. Advanced solar receiver conceptual design study

    NASA Technical Reports Server (NTRS)

    Kesseli, J. B.; Lacy, D. E.

    1987-01-01

    High temperature solar dynamic Brayton and Stirling receivers are investigated as candidate electrical power generating systems for future LEO missions. These receivers are smaller and more efficient than conventional receivers, and they offer less structural complexity and fewer thermal stress problems. Use of the advanced Direct Absorption Storage Receiver allows many of the problems associated with working with high-volumetric-change phase-change materials to be avoided. A specific mass reduction of about 1/3 with respect to the baseline receiver has been realized.

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  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. 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.

  12. Optical superheterodyne receiver.

    NASA Technical Reports Server (NTRS)

    Duval, K.; Lang, K.; Lucy, R. F.; Peters, C. J.

    1967-01-01

    Optical communication experiments to compare coherent and noncoherent optical detection fading characteristics in different weather conditions, using laser transmitter and optical superheterodyne receiver

  13. A minimalist approach to receiver architecture

    NASA Technical Reports Server (NTRS)

    Collins, O.

    1991-01-01

    New signal processing techniques are described for Deep Space Network radios and a proposed receiver architecture is presented, as well as experimental results on this new receiver's analog front end. The receiver's design employs direct downconversion rather than high speed digitization, and it is just as suitable for use as a space based probe relay receiver as it is for installation at a ground antenna. The advantages of having an inexpensive, shoe box size receiver, which could be carried around to antennas of opportunity, used for spacecraft testing or installed in the base of every antenna in a large array are the force behind this project.

  14. 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.

  15. The USDOE Reflux Receiver Development Program

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Klimas, P.C.; Andraka, C.E.; Moreno, J.B.

    1992-01-01

    The US DOE's Solar Thermal Electric Program, through its Sandia and Renewable Energy National Laboratories, has been actively developing liquid metal reflux receivers for application to modular parabolic dish concentrator/Stirling cycle converter solar energy systems. These systems are intended for use in high-value remote and grid-connected utility applications. The liquid-metal reflux-receiver concept was selected because this type of solar receiver (1) can optically mate a given dish with a given engine, and (2) can provide an isothermal environment for the high-temperature heat-input portion of the l engine, thus enhancing reliability. The Program is investigating two types of reflux receivers: heatmore » pipes and pool boilers. Sintered-nickel-wick sodium heat-pipe receivers rated at 30 kW[sub t] have been extensively tested as part of DOE/Cummins cooperative commercialization programs. One recent test article was tested at rated and power temperature for 500 hours. This same receiver demonstrated a 40 kW[sub t] throughput, believed to be the most ever for a solar heated heat-pipe receiver. Another 30-kW[sub t] sodium heat-pipe receiver, this one using a stainless-steel-screen wick design, was also tested as part of these cooperative programs. Much of experimental reflux receiver work conducted at the program's laboratories involves the pool-boiler concept. During nearly 50 hours of solar testing, the Sandia 75-kW[sub t] pool-boiler receiver demonstrated stable sodium boiling over a wide range of temperatures. Hot restarts after simulated cloud passages were investigated using various quantities of added non-condensible gases. Novel x-ray techniques provided information on instantaneous void fractions in the receiver. Present work is focusing on longer lived designs having low-cost, high-strength boiling surface enhancements and using eutectic NaK as the working fluid. The paper will summarize the developments leading to the present and describe future plans.« less

  16. The USDOE Reflux Receiver Development Program

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Klimas, P.C.; Andraka, C.E.; Moreno, J.B.

    1992-11-01

    The US DOE`s Solar Thermal Electric Program, through its Sandia and Renewable Energy National Laboratories, has been actively developing liquid metal reflux receivers for application to modular parabolic dish concentrator/Stirling cycle converter solar energy systems. These systems are intended for use in high-value remote and grid-connected utility applications. The liquid-metal reflux-receiver concept was selected because this type of solar receiver (1) can optically mate a given dish with a given engine, and (2) can provide an isothermal environment for the high-temperature heat-input portion of the l engine, thus enhancing reliability. The Program is investigating two types of reflux receivers: heatmore » pipes and pool boilers. Sintered-nickel-wick sodium heat-pipe receivers rated at 30 kW{sub t} have been extensively tested as part of DOE/Cummins cooperative commercialization programs. One recent test article was tested at rated and power temperature for 500 hours. This same receiver demonstrated a 40 kW{sub t} throughput, believed to be the most ever for a solar heated heat-pipe receiver. Another 30-kW{sub t} sodium heat-pipe receiver, this one using a stainless-steel-screen wick design, was also tested as part of these cooperative programs. Much of experimental reflux receiver work conducted at the program`s laboratories involves the pool-boiler concept. During nearly 50 hours of solar testing, the Sandia 75-kW{sub t} pool-boiler receiver demonstrated stable sodium boiling over a wide range of temperatures. Hot restarts after simulated cloud passages were investigated using various quantities of added non-condensible gases. Novel x-ray techniques provided information on instantaneous void fractions in the receiver. Present work is focusing on longer lived designs having low-cost, high-strength boiling surface enhancements and using eutectic NaK as the working fluid. The paper will summarize the developments leading to the present and describe future plans.« less

  17. 30 CFR 56.13011 - Air receiver tanks.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Air receiver tanks. 56.13011 Section 56.13011... § 56.13011 Air receiver tanks. Air receiver tanks shall be equipped with one or more automatic pressure... the maximum allowable working pressure in a receiver tank by not more than 10 percent. Air receiver...

  18. Industrial Technology Modernization Program. Project 28. Automation of Receiving, Receiving Inspection and Stores

    DTIC Science & Technology

    1987-06-15

    001 GENERAL DYNAMICS 00 FORT WORTH DIVISION INDUSTRIAL TECHNOLOGY MODERNIZATION PROGRAM Phase 2 Final Project Repc t JUNG 0 ?7 PROJECT 28 AUTOMATION...DYNAMICS FORT WORTH DIVISION INDUSTRIAL TECHNOLOGY MODERNIZATION PROGRAM Phase 2 Final Project Report PROJECT 28 AUTOMATION OF RECEIVING, RECEIVING...13 6 PROJECT ASSUMPTIONS 20 7 PRELIMINARY/FINAL DESIGN AND FINDINGS 21 8 SYSTEM/EQUIPMENT/MACHINING SPECIFICATIONS 37 9 VENDOR/ INDUSTRY ANALYSIS

  19. 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.

  20. 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 other...

  1. 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 cleaning...

  2. 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 other...

  3. 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 cleaning...

  4. 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 cleaning...

  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 other...

  6. 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 other...

  7. 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 cleaning...

  8. 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 cleaning...

  9. 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 other...

  10. 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.

  11. 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 in...

  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 in...

  13. 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 in...

  14. 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 in...

  15. 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 in...

  16. Receiver System: Lessons Learned From Solar Two

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    LITWIN, ROBERT Z.; PACHECO, JAMES E.

    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,more » 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.« less

  17. 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.

  18. Water jacket for solid particle solar receiver

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wasyluk, David T.

    A solar receiver includes: water jacket panels each having a light-receiving side and a back side with a watertight sealed plenum defined in-between; light apertures passing through the watertight sealed plenums to receive light from the light-receiving sides of the water jacket panels; a heat transfer medium gap defined between the back sides of the water jacket panels and a cylindrical back plate; and light channeling tubes optically coupled with the light apertures and extending into the heat transfer medium gap. In some embodiments ends of the light apertures at the light receiving side of the water jacket panel aremore » welded together to define at least a portion of the light-receiving side. A cylindrical solar receiver may be constructed using a plurality of such water jacket panels arranged with their light-receiving sides facing outward.« less

  19. 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.

  20. 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.

  1. Adaptive receiver structures for asynchronous CDMA systems

    NASA Astrophysics Data System (ADS)

    Rapajic, Predrag B.; Vucetic, Branka S.

    1994-05-01

    Adaptive linear and decision feedback receiver structures for coherent demodulation in asynchronous code division multiple access (CDMA) systems are considered. It is assumed that the adaptive receiver has no knowledge of the signature waveforms and timing of other users. The receiver is trained by a known training sequence prior to data transmission and continuously adjusted by an adaptive algorithm during data transmission. The proposed linear receiver is as simple as a standard single-user detector receiver consisting of a matched filter with constant coefficients, but achieves essential advantages with respect to timing recovery, multiple access interference elimination, near/far effect, narrowband and frequency-selective fading interference suppression, and user privacy. An adaptive centralized decision feedback receiver has the same advantages of the linear receiver but, in addition, achieves a further improvement in multiple access interference cancellation at the expense of higher complexity. The proposed receiver structures are tested by simulation over a channel with multipath propagation, multiple access interference, narrowband interference, and additive white Gaussian noise.

  2. 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.

  3. Receiver design and performance characteristics

    NASA Technical Reports Server (NTRS)

    Simon, M. K.; Yuen, J. H.

    1982-01-01

    The basic design, principles of operation, and characteristics of deep space communications receivers are examined. In particular, the basic fundamentals of phase-locked loop and Costas loop receivers used for synchronization, tracking, and demodulation of phase-coherent signals in residual carrier and suppressed carrier systems are addressed.

  4. 30 CFR 57.13011 - Air receiver tanks.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Air receiver tanks. 57.13011 Section 57.13011... Boilers § 57.13011 Air receiver tanks. Air receiver tanks shall be equipped with one or more automatic... exceeding the maximum allowable working pressure in a receiver tank by not more than 10 percent. Air...

  5. 30 CFR 57.13011 - Air receiver tanks.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Air receiver tanks. 57.13011 Section 57.13011... Boilers § 57.13011 Air receiver tanks. Air receiver tanks shall be equipped with one or more automatic... exceeding the maximum allowable working pressure in a receiver tank by not more than 10 percent. Air...

  6. 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.

  7. 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.

  8. 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.

  9. 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

  10. 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.

  11. 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.

  12. 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.

  13. Time domain multiplexed spatial division multiplexing receiver.

    PubMed

    van Uden, Roy G H; Okonkwo, Chigo M; Chen, Haoshuo; de Waardt, Hugo; Koonen, Antonius M J

    2014-05-19

    A novel time domain multiplexed (TDM) spatial division multiplexing (SDM) receiver which allows for the reception of >1 dual polarization mode with a single coherent receiver, and corresponding 4-port oscilloscope, is experimentally demonstrated. Received by two coherent receivers and respective 4-port oscilloscopes, a 3 mode transmission of 28GBaud QPSK, 8, 16, and 32QAM over 41.7km of few-mode fiber demonstrates the performance of the TDM-SDM receiver with respect to back-to-back. In addition, by using carrier phase estimation employing one digital phase locked loop per output, the frequency offset between the transmitter laser and local oscillator is shown to perform similar to previous work which employs 3 coherent receivers and 4-port oscilloscopes which are dedicated to the reception of each the three modes.

  14. 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.

  15. Effects of Oxytocin Administration on Receiving Help.

    PubMed

    Human, Lauren J; Woolley, Joshua D; Mendes, Wendy Berry

    2017-11-27

    Receiving help can be a "mixed blessing." Despite the many psychosocial benefits it can carry, it sometimes has negative psychological consequences, such as loss in self-esteem or enhanced guilt. It is, therefore, important to understand the factors that modify responses to receiving help from others. We explored the role of the hormone oxytocin (OT) on affective and social responses to receiving help, given the putative role of OT in social bonding and attunement. To this end, we manipulated whether help was received from a same-sex interaction partner (confederate) versus a control condition, crossed with a double-blind administration of intranasal OT (vs. placebo), and examined subjective and observer-rated participant responses to help. We observed significant interactions between OT and the help manipulation. In the placebo condition, receiving help from the interaction partner compared with the control condition had negative consequences, such that participants reported greater negative affect and came to view themselves and their interaction partners more negatively after interacting together on several tasks. What is important, however, is that OT administration buffered against these negative subjective responses to receiving help. Further, outside observers rated participants who received OT administration as expressing greater happiness and gratitude in response to help, relative to those who received placebo. In sum, in the context of receiving help from a stranger, oxytocin administration fostered more positive affective and social responses. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  16. GNSS Receiver Identification Using Clock-Derived Metrics.

    PubMed

    Borio, Daniele; Gioia, Ciro; Cano Pons, Eduardo; Baldini, Gianmarco

    2017-09-15

    Falsifying Global Navigation Satellite System (GNSS) data with a simulator or with a fake receiver can have a significant economic or safety impact in many transportation applications where Position, Velocity and Time (PVT) are used to enforce a regulation. In this context, the authentication of the source of the PVT data (i.e., the GNSS receiver) is a requirement since data faking can become a serious threat. Receiver fingerprinting techniques represent possible countermeasures to verify the authenticity of a GNSS receiver and of its data. Herein, the potential of clock-derived metrics for GNSS receiver fingerprinting is investigated, and a filter approach is implemented for feature selection. Novel experimental results show that three intrinsic features are sufficient to identify a receiver. Moreover, the adopted technique is time effective as data blocks of about 40 min are sufficient to produce stable features for fingerprinting.

  17. Full-wave receiver architecture for the homodyne motion sensor

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Haugen, Peter C.; Dallum, Gregory E.; Welsh, Patrick A.

    A homodyne motion sensor or detector based on ultra-wideband radar utilizes the entire received waveform through implementation of a voltage boosting receiver. The receiver includes a receiver input and a receiver output. A first diode is connected to the receiver output. A first charge storage capacitor is connected from between the first diode and the receiver output to ground. A second charge storage capacitor is connected between the receiver input and the first diode. A second diode is connected from between the second charge storage capacitor and the first diode to ground. The dual diode receiver performs voltage boosting ofmore » a RF signal received at the receiver input, thereby enhancing receiver sensitivity.« less

  18. Full-wave receiver architecture for the homodyne motion sensor

    DOEpatents

    Haugen, Peter C; Dallum, Gregory E; Welsh, Patrick A; Romero, Carlos E

    2013-11-19

    A homodyne motion sensor or detector based on ultra-wideband radar utilizes the entire received waveform through implementation of a voltage boosting receiver. The receiver includes a receiver input and a receiver output. A first diode is connected to the receiver output. A first charge storage capacitor is connected from between the first diode and the receiver output to ground. A second charge storage capacitor is connected between the receiver input and the first diode. A second diode is connected from between the second charge storage capacitor and the first diode to ground. The dual diode receiver performs voltage boosting of a RF signal received at the receiver input, thereby enhancing receiver sensitivity.

  19. Sensitivity analysis of heliostat aiming strategies and receiver size on annual thermal production of a molten salt external receiver

    NASA Astrophysics Data System (ADS)

    Servert, Jorge; González, Ana; Gil, Javier; López, Diego; Funes, Jose Felix; Jurado, Alfonso

    2017-06-01

    Even though receiver size and aiming strategy are to be jointly analyzed to optimize the thermal energy that can be extracted from a solar tower receiver, customarily, they have been studied as separated problems. The main reason is the high-level of detail required to define aiming strategies, which are often simplified in annual simulation models. Aiming strategies are usually focused on obtaining a homogeneous heat flux on the central receiver, with the goal to minimize the maximum heat flux value that may lead to damaging it. Some recent studies have addressed the effect of different aiming strategies on different receiver types, but they have only focused on the optical efficiency. The receiver size is also an additional parameter that has to be considered: larger receiver sizes provide a larger aiming surface and a reduction on spillage losses, but require higher investment while penalizing the thermal performance of the receiver due to the greater external convection losses. The present paper presents a sensitivity analysis of both factors for a predefined solar field at a fixed location, using a central receiver and molten salts as HTF. The analysis includes the design point values and annual energy outputs comparing the effect on the optical performance (measured using a spillage factor) and thermal energy production.

  20. Open fitting: performance verification of receiver in the ear and receiver in the aid.

    PubMed

    Mondelli, Maria Fernanda Capoani Garcia; Garcia, Tatiana Manfrini; Hashimoto, Fabiana Midori Tokuhara; Rocha, Andressa Vital

    2015-01-01

    To verify the receiver in the ear and receiver in the aid adaptations by measuring in situ the speech perception and users' level of satisfaction. The study was approved by the research ethics committee (Process: 027/2011). Twenty subjects older than 18 years with audiological diagnosis of mild and moderate bilateral descending sensorineural hearing loss were evaluated. The subjects were divided into two groups, where G1 (group 1) was fitted with open-fit hearing aids with the built-in receiver unit (receiver in the ear) and G2 (group 2) was fitted with open-fit hearing aids with RITE. A probe microphone measurement was performed to check the gain and output provided by the amplification and for assessment of speech perception with Hearing in Noise Test with and without hearing aids. After a period of six weeks of use without interruption, the subjects returned for follow-up and answered the Satisfaction with Amplification in Daily Life questionnaire, and were again subjected to Hearing in Noise Test. Both groups presented better test results for speech recognition in the presence of noise. Groups 1 and 2 were satisfied with the use of hearing aids and improved speech recognition in silent and noisy situations with hearing aids. Copyright © 2014 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

  1. Development of advanced space solar dynamic receiver

    NASA Astrophysics Data System (ADS)

    Abe, Yoshiyuki; Tanaka, Kotaro; Nomura, Osami; Kanari, Katsuhiko; Takahashi, Yoshio; Kamimoto, Masayuki

    Work on an advanced solar dynamic receiver is reviewed. The authors first describe the component test of the receiver tube with LiF in metallic containers, which was performed in a closed high-temperature He-Xe loop. They then give the details of the development of composite phase change materials, such as ceramic/molten salts or carbon/molten salts for advanced receiver concepts. As for SiC/LiF composites, the performance test of the receiver component will soon be ready to begin.

  2. 47 CFR 80.290 - Auxiliary receiving antenna.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 5 2013-10-01 2013-10-01 false Auxiliary receiving antenna. 80.290 Section 80... antenna. An auxiliary receiving antenna must be provided when necessary to avoid unauthorized interruption or reduced efficiency of the required watch because the normal receiving antenna is not available...

  3. 47 CFR 80.290 - Auxiliary receiving antenna.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 5 2011-10-01 2011-10-01 false Auxiliary receiving antenna. 80.290 Section 80... antenna. An auxiliary receiving antenna must be provided when necessary to avoid unauthorized interruption or reduced efficiency of the required watch because the normal receiving antenna is not available...

  4. 47 CFR 80.290 - Auxiliary receiving antenna.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 5 2014-10-01 2014-10-01 false Auxiliary receiving antenna. 80.290 Section 80... antenna. An auxiliary receiving antenna must be provided when necessary to avoid unauthorized interruption or reduced efficiency of the required watch because the normal receiving antenna is not available...

  5. 47 CFR 80.290 - Auxiliary receiving antenna.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 5 2012-10-01 2012-10-01 false Auxiliary receiving antenna. 80.290 Section 80... antenna. An auxiliary receiving antenna must be provided when necessary to avoid unauthorized interruption or reduced efficiency of the required watch because the normal receiving antenna is not available...

  6. 47 CFR 80.290 - Auxiliary receiving antenna.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Auxiliary receiving antenna. 80.290 Section 80... antenna. An auxiliary receiving antenna must be provided when necessary to avoid unauthorized interruption or reduced efficiency of the required watch because the normal receiving antenna is not available...

  7. Receiver concepts for data transmission at 10 microns

    NASA Astrophysics Data System (ADS)

    Scholtz, A. L.; Philipp, H. K.; Leeb, W. R.

    1984-05-01

    Receivers for digitally modulated CO2 laser signals are compared. Incoherent heterodyne receivers and coherent homodyne setups, including the linear phase locked loop (PLL) receiver, the low intermediate frequency translation loop, and the Costas loop receiver were studied. Experiments covered the homodyne systems, emphasizing the linear PLL receiver. Reliable phase lock of the receiver is achieved at carrier levels as low as 3 nW. Reception of signals phase shift keyed with a data rate of up to 150 Mbit/sec is demonstrated at subnanowatt sideband power levels.

  8. Decoding algorithm for vortex communications receiver

    NASA Astrophysics Data System (ADS)

    Kupferman, Judy; Arnon, Shlomi

    2018-01-01

    Vortex light beams can provide a tremendous alphabet for encoding information. We derive a symbol decoding algorithm for a direct detection matrix detector vortex beam receiver using Laguerre Gauss (LG) modes, and develop a mathematical model of symbol error rate (SER) for this receiver. We compare SER as a function of signal to noise ratio (SNR) for our algorithm and for the Pearson correlation algorithm. To our knowledge, this is the first comprehensive treatment of a decoding algorithm of a matrix detector for an LG receiver.

  9. Zero-power receiver

    DOEpatents

    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.

  10. Support and maneuvering apparatus for solar energy receivers

    DOEpatents

    Murphy, L.M.

    1988-07-28

    A support and maneuvering apparatus is disclosed for a solar energy receiving device adapted for receiving and concentrating solar energy and having a central axis extending through the center thereof. The apparatus includes a frame for mounting the perimeter of said solar energy receiving device. A support member extends along the central axis of the receiving device and has a base end passing through the center of the receiving device and an outer distal end adapted for carrying a solar energy receiving and conversion mechanism. A variable tension mechanism interconnects the support member with the frame to provide stiffening for the support member and the frame and to assist in the alignment of the frame to optimize the optical efficiency of the solar energy receiving device. A rotatable base is provided, and connecting members extend from the base for pivotable attachment to the frame at spaced positions therealong. Finally, an elevation assembly is connected to the receiving device for selectively pivoting the receiving about an axis defined between the attachment positions of the connecting members on the frame. 4 figs.

  11. Support and maneuvering apparatus for solar energy receivers

    DOEpatents

    Murphy, Lawrence M.

    1989-01-01

    A support and maneuvering apparatus is disclosed for a solar energy receiving device adpated for receiving and concentrating solar energy and having a central axis extending through the center thereof. The apparatus includes a frame for mounting the perimeter of said solar energy receiving device. A support member extends along the central axis of the receiving device and has a base end passing through the center of the receiving device and an outer distal end adapted for carrying a solar energy receiving and conversion mechanism. A variable tension mechanism interconnects the support member with the frame to provide stiffening for the support member and the frame and to assist in the alignment of the frame to optimize the optical efficiency of the solar energy receiving device. A rotatable base is provided, and connecting members extend from the base for pivotable attachment to the frame at spaced positions therealong. Finally, an elevation assembly is connected to the receiving device for selectively pivoting the receiving device about an axis defined between the attachment positions of the connecting members on the frame.

  12. PiVoT GPS Receiver

    NASA Technical Reports Server (NTRS)

    Wennersten, Miriam; Banes, Vince; Boegner, Greg; Clagnett, Charles; Dougherty, Lamar; Edwards, Bernard; Roman, Joe; Bauer, Frank H. (Technical Monitor)

    2001-01-01

    NASA Goddard Space Flight Center has built an open architecture, 24 channel spaceflight Global Positioning System (GPS) receiver. The compact PCI 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 works at a lower signal to noise ratio than the original Builder 2 board. It also hosts an improved clock oscillator. The PiVoT software is based on the original Piessey Builder 2 software ported to the Linux operating system. The software is posix compliant and can be easily 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 compact PCI card containing the microprocessor and the GPS receiver optimized for use above the GPS constellation.

  13. 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.

  14. Clinical implications of somatic mutations in aplastic anemia and myelodysplastic syndrome in genomic age.

    PubMed

    Maciejewski, Jaroslaw P; Balasubramanian, Suresh K

    2017-12-08

    Recent technological advances in genomics have led to the discovery of new somatic mutations and have brought deeper insights into clonal diversity. This discovery has changed not only the understanding of disease mechanisms but also the diagnostics and clinical management of bone marrow failure. The clinical applications of genomics include enhancement of current prognostic schemas, prediction of sensitivity or refractoriness to treatments, and conceptualization and selective application of targeted therapies. However, beyond these traditional clinical aspects, complex hierarchical clonal architecture has been uncovered and linked to the current concepts of leukemogenesis and stem cell biology. Detection of clonal mutations, otherwise typical of myelodysplastic syndrome, in the course of aplastic anemia (AA) and paroxysmal nocturnal hemoglobinuria has led to new pathogenic concepts in these conditions and created a new link between AA and its clonal complications, such as post-AA and paroxysmal nocturnal hemoglobinuria. Distinctions among founder vs subclonal mutations, types of clonal evolution (linear or branching), and biological features of individual mutations (sweeping, persistent, or vanishing) will allow for better predictions of the biologic impact they impart in individual cases. As clonal markers, mutations can be used for monitoring clonal dynamics of the stem cell compartment during physiologic aging, disease processes, and leukemic evolution. © 2016 by The American Society of Hematology. All rights reserved.

  15. 30 CFR 56.13011 - Air receiver tanks.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Air receiver tanks. 56.13011 Section 56.13011... SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Compressed Air and Boilers § 56.13011 Air receiver tanks. Air receiver tanks shall be equipped with one or more automatic pressure...

  16. 30 CFR 56.13011 - Air receiver tanks.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Air receiver tanks. 56.13011 Section 56.13011... SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Compressed Air and Boilers § 56.13011 Air receiver tanks. Air receiver tanks shall be equipped with one or more automatic pressure...

  17. 30 CFR 57.13011 - Air receiver tanks.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Air receiver tanks. 57.13011 Section 57.13011... SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Compressed Air and Boilers § 57.13011 Air receiver tanks. Air receiver tanks shall be equipped with one or more automatic...

  18. 30 CFR 56.13011 - Air receiver tanks.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Air receiver tanks. 56.13011 Section 56.13011... SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Compressed Air and Boilers § 56.13011 Air receiver tanks. Air receiver tanks shall be equipped with one or more automatic pressure...

  19. 30 CFR 57.13011 - Air receiver tanks.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Air receiver tanks. 57.13011 Section 57.13011... SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Compressed Air and Boilers § 57.13011 Air receiver tanks. Air receiver tanks shall be equipped with one or more automatic...

  20. 30 CFR 56.13011 - Air receiver tanks.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Compressed Air and Boilers § 56.13011 Air receiver tanks. Air receiver tanks shall be equipped with one or more automatic pressure... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Air receiver tanks. 56.13011 Section 56.13011...

  1. 30 CFR 57.13011 - Air receiver tanks.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Compressed Air and Boilers § 57.13011 Air receiver tanks. Air receiver tanks shall be equipped with one or more automatic... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Air receiver tanks. 57.13011 Section 57.13011...

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 49 CFR 236.730 - Coil, receiver.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ..., MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Definitions § 236.730 Coil, receiver. Concentric layers of insulated wire wound around the core of a receiver of an automatic train stop, train control or cab signal device on a locomotive. ...

  7. 21 CFR 1020.10 - Television receivers.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ..., under normal usage, are not accessible to the user. (4) Television receiver means an electronic product designed to receive and display a television picture through broadcast, cable, or closed circuit television... from that component or circuit failure which maximizes x-radiation emissions. (4) Critical component...

  8. 21 CFR 1020.10 - Television receivers.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ..., under normal usage, are not accessible to the user. (4) Television receiver means an electronic product designed to receive and display a television picture through broadcast, cable, or closed circuit television... from that component or circuit failure which maximizes x-radiation emissions. (4) Critical component...

  9. 21 CFR 1020.10 - Television receivers.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ..., under normal usage, are not accessible to the user. (4) Television receiver means an electronic product designed to receive and display a television picture through broadcast, cable, or closed circuit television... from that component or circuit failure which maximizes x-radiation emissions. (4) Critical component...

  10. 21 CFR 1020.10 - Television receivers.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ..., under normal usage, are not accessible to the user. (4) Television receiver means an electronic product designed to receive and display a television picture through broadcast, cable, or closed circuit television... from that component or circuit failure which maximizes x-radiation emissions. (4) Critical component...

  11. 21 CFR 1020.10 - Television receivers.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ..., under normal usage, are not accessible to the user. (4) Television receiver means an electronic product designed to receive and display a television picture through broadcast, cable, or closed circuit television... from that component or circuit failure which maximizes x-radiation emissions. (4) Critical component...

  12. 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.

  13. 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.

  14. 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).

  15. Modified timing module for Loran-C receiver

    NASA Technical Reports Server (NTRS)

    Lilley, R. W.

    1983-01-01

    Full hardware documentation is provided for the circuit card implementing the Loran-C timing loop, and the receiver event-mark and re-track functions. This documentation is to be combined with overall receiver drawings to form the as-built record for this device. Computer software to support this module is integrated with the remainder of the receiver software, in the LORPROM program.

  16. Optical Vector Receiver Operating Near the Quantum Limit

    NASA Astrophysics Data System (ADS)

    Vilnrotter, V. A.; Lau, C.-W.

    2005-05-01

    An optical receiver concept for binary signals with performance approaching the quantum limit at low average-signal energies is developed and analyzed. A conditionally nulling receiver that reaches the quantum limit in the absence of background photons has been devised by Dolinar. However, this receiver requires ideal optical combining and complicated real-time shaping of the local field; hence, it tends to be difficult to implement at high data rates. A simpler nulling receiver that approaches the quantum limit without complex optical processing, suitable for high-rate operation, had been suggested earlier by Kennedy. Here we formulate a vector receiver concept that incorporates the Kennedy receiver with a physical beamsplitter, but it also utilizes the reflected signal component to improve signal detection. It is found that augmenting the Kennedy receiver with classical coherent detection at the auxiliary beamsplitter output, and optimally processing the vector observations, always improves on the performance of the Kennedy receiver alone, significantly so at low average-photon rates. This is precisely the region of operation where modern codes approach channel capacity. It is also shown that the addition of background radiation has little effect on the performance of the coherent receiver component, suggesting a viable approach for near-quantum-limited performance in high background environments.

  17. Improved Noncoherent UWB Receiver for Implantable Biomedical Devices.

    PubMed

    Nagaraj, Santosh; Rassam, Faris G

    2016-10-01

    The purpose of this paper is to describe a novel noncoherent receiver architecture to improve the error performance of impulse-radio ultrawideband (IR-UWB) in bioimplanted devices. IR-UWB receivers based on energy detection are popular in biomedical applications owing to the low implementation cost/complexity and the high data rates that UWB can potentially support. Implanted devices suffer from severe frequency-dependent attenuation due to human blood and tissues, while most receivers in the literature are designed based on commonly used indoor wireless channel models. We propose a novel receiver design that is based on judiciously combining the energies in different bands of the signal spectrum with a weighted linear combiner. We derive the optimum coefficients of the combiner. The receiver retains almost all of the advantages of a conventional noncoherent detector, but can also compensate for attenuation properties of blood/tissue. The receiver design can be adapted to different implantation depths by simply varying the combiner weights. The receiver can also be considered to be a simple form of equalizer for noncoherent reception. Our simulations show about 2-dB improvement over other commonly used receivers. This receiver design is significant in that it can enhance critical battery life of implanted transmitters.

  18. 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.

  19. 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

  20. 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.

  1. 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.

  2. QPPM receiver for free-space laser communications

    NASA Technical Reports Server (NTRS)

    Budinger, J. M.; Mohamed, J. H.; Nagy, L. A.; Lizanich, P. J.; Mortensen, D. J.

    1994-01-01

    A prototype receiver developed at NASA Lewis Research Center for direct detection and demodulation of quaternary pulse position modulated (QPPM) optical carriers is described. The receiver enables dual-channel communications at 325-Megabits per second (Mbps) per channel. The optical components of the prototype receiver are briefly described. The electronic components, comprising the analog signal conditioning, slot clock recovery, matched filter and maximum likelihood data recovery circuits are described in more detail. A novel digital symbol clock recovery technique is presented as an alternative to conventional analog methods. Simulated link degradations including noise and pointing-error induced amplitude variations are applied. The bit-error-rate performance of the electronic portion of the prototype receiver under varying optical signal-to-noise power ratios is found to be within 1.5-dB of theory. Implementation of the receiver as a hybrid of analog and digital application specific integrated circuits is planned.

  3. 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.

  4. Interference-Detection Module in a Digital Radar Receiver

    NASA Technical Reports Server (NTRS)

    Fischman, Mark; Berkun, Andrew; Chu, Anhua; Freedman, Adam; Jourdan, Michael; McWatters, Dalia; Paller, Mimi

    2009-01-01

    A digital receiver in a 1.26-GHz spaceborne radar scatterometer now undergoing development includes a module for detecting radio-frequency interference (RFI) that could contaminate scientific data intended to be acquired by the scatterometer. The role of the RFI-detection module is to identify time intervals during which the received signal is likely to be contaminated by RFI and thereby to enable exclusion, from further scientific data processing, of signal data acquired during those intervals. The underlying concepts of detection of RFI and rejection of RFI-contaminated signal data are also potentially applicable in advanced terrestrial radio receivers, including software-defined radio receivers in general, receivers in cellular telephones and other wireless consumer electronic devices, and receivers in automotive collision-avoidance radar systems.

  5. 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.

  6. 7 CFR 966.124 - Approved receiver.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 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...

  7. A digital-receiver for the MurchisonWidefield Array

    NASA Astrophysics Data System (ADS)

    Prabu, Thiagaraj; Srivani, K. S.; Roshi, D. Anish; Kamini, P. A.; Madhavi, S.; Emrich, David; Crosse, Brian; Williams, Andrew J.; Waterson, Mark; Deshpande, Avinash A.; Shankar, N. Udaya; Subrahmanyan, Ravi; Briggs, Frank H.; Goeke, Robert F.; Tingay, Steven J.; Johnston-Hollitt, Melanie; R, Gopalakrishna M.; Morgan, Edward H.; Pathikulangara, Joseph; Bunton, John D.; Hampson, Grant; Williams, Christopher; Ord, Stephen M.; Wayth, Randall B.; Kumar, Deepak; Morales, Miguel F.; deSouza, Ludi; Kratzenberg, Eric; Pallot, D.; McWhirter, Russell; Hazelton, Bryna J.; Arcus, Wayne; Barnes, David G.; Bernardi, Gianni; Booler, T.; Bowman, Judd D.; Cappallo, Roger J.; Corey, Brian E.; Greenhill, Lincoln J.; Herne, David; Hewitt, Jacqueline N.; Kaplan, David L.; Kasper, Justin C.; Kincaid, Barton B.; Koenig, Ronald; Lonsdale, Colin J.; Lynch, Mervyn J.; Mitchell, Daniel A.; Oberoi, Divya; Remillard, Ronald A.; Rogers, Alan E.; Salah, Joseph E.; Sault, Robert J.; Stevens, Jamie B.; Tremblay, S.; Webster, Rachel L.; Whitney, Alan R.; Wyithe, Stuart B.

    2015-03-01

    An FPGA-based digital-receiver has been developed for a low-frequency imaging radio interferometer, the Murchison Widefield Array (MWA). The MWA, located at the Murchison Radio-astronomy Observatory (MRO) in Western Australia, consists of 128 dual-polarized aperture-array elements (tiles) operating between 80 and 300 MHz, with a total processed bandwidth of 30.72 MHz for each polarization. Radio-frequency signals from the tiles are amplified and band limited using analog signal conditioning units; sampled and channelized by digital-receivers. The signals from eight tiles are processed by a single digital-receiver, thus requiring 16 digital-receivers for the MWA. The main function of the digital-receivers is to digitize the broad-band signals from each tile, channelize them to form the sky-band, and transport it through optical fibers to a centrally located correlator for further processing. The digital-receiver firmware also implements functions to measure the signal power, perform power equalization across the band, detect interference-like events, and invoke diagnostic modes. The digital-receiver is controlled by high-level programs running on a single-board-computer. This paper presents the digital-receiver design, implementation, current status, and plans for future enhancements.

  8. 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.

  9. Myasthenia gravis: the role of complement at the neuromuscular junction.

    PubMed

    Howard, James F

    2018-01-01

    Generalized myasthenia gravis (gMG) is a rare autoimmune disorder characterized by skeletal muscle weakness caused by disrupted neurotransmission at the neuromuscular junction (NMJ). Approximately 74-88% of patients with gMG have acetylcholine receptor (AChR) autoantibodies. Complement plays an important role in innate and antibody-mediated immunity, and activation and amplification of complement results in the formation of membrane attack complexes (MACs), lipophilic proteins that damage cell membranes. The role of complement in gMG has been demonstrated in animal models and patients. Studies in animals lacking specific complement proteins have confirmed that MAC formation is required to induce experimental autoimmune MG (EAMG) and NMJ damage. Complement inhibition in EAMG models can prevent disease induction and reverse its progression. Patients with anti-AChR + MG have autoantibodies and MACs present at NMJs. Damaged NMJs are associated with more severe disease, fewer AChRs, and MACs in synaptic debris. Current MG therapies do not target complement directly. Eculizumab is a humanized monoclonal antibody that inhibits cleavage of complement protein C5, preventing MAC formation. Eculizumab treatment improved symptoms compared with placebo in a phase II study in patients with refractory gMG. Direct complement inhibition could preserve NMJ physiology and muscle function in patients with anti-AChR + gMG. © 2017 The Authors. Annals of the New York Academy of Sciences published by Wiley Periodicals Inc. on behalf of The New York Academy of Sciences.

  10. Concentrated solar power generation using solar receivers

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Anderson, Bruce N.; Treece, William Dean; Brown, Dan

    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.

  11. RF subsystem design for microwave communication receivers

    NASA Astrophysics Data System (ADS)

    Bickford, W. J.; Brodsky, W. G.

    A system review of the RF subsystems of (IFF) transponders, tropscatter receivers and SATCOM receivers is presented. The quantity potential for S-band and X-band IFF transponders establishes a baseline requirement. From this, the feasibility of a common design for these and other receivers is evaluated. Goals are established for a GaAs MMIC (monolithic microwave integrated circuit) device and related local oscillator preselector and self-test components.

  12. Long-Term Heating to Improve Receiver Performance

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Glatzmaier, Greg C.; Cable, Robert; Newmarker, Marc

    The buildup of hydrogen in the heat transfer fluid (HTF) that circulates through components of parabolic trough power plants decreases receiver thermal efficiency, and ultimately, it decreases plant performance and electricity output. The generation and occurrence of hydrogen in the HTF provides the driving force for hydrogen to permeate from the HTF through the absorber tube wall and into the receiver annulus. Getters adsorb hydrogen from the annulus volume until they saturate and are no longer able to maintain low hydrogen pressure. The increase in hydrogen pressure within the annulus significantly degrades thermal performance of the receiver and decreases overallmore » power-plant efficiency. NREL and Acciona Energy North America (Acciona) are developing a method to control the levels of dissolved hydrogen in the circulating HTF. The basic approach is to remove hydrogen from the expansion tanks of the HTF subsystem at a rate that maintains hydrogen in the circulating HTF to a target level. Full-plant steady-state models developed by the National Renewable Energy Laboratory (NREL) predict that if hydrogen is removed from the HTF within the expansion tanks, the HTF that circulates through the collector field remains essentially free of hydrogen until the HTF returns to the power block in the hot headers. One of the key findings of our modeling is the prediction that hydrogen will reverse-permeate out of the receiver annulus if dissolved hydrogen in the HTF is kept sufficiently low. To test this prediction, we performed extended heating of an in-service receiver that initially had high levels of hydrogen in its annulus. The heating was performed using NREL's receiver test stand. Results of our testing showed that receiver heat loss steadily decreased with daily heating, resulting in a corresponding improvement in receiver thermal efficiency.« less

  13. 24 CFR 982.355 - Portability: Administration by receiving PHA.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... by the receiving PHA. (1) If funding is available under the consolidated ACC for the receiving PHA... consolidated ACC for the receiving PHA tenant-based program. (2) HUD may require that the receiving PHA absorb... families to the receiving PHA from funds available under the initial PHA ACC. (2) HUD may provide...

  14. 24 CFR 982.355 - Portability: Administration by receiving PHA.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... by the receiving PHA. (1) If funding is available under the consolidated ACC for the receiving PHA... consolidated ACC for the receiving PHA tenant-based program. (2) HUD may require that the receiving PHA absorb... families to the receiving PHA from funds available under the initial PHA ACC. (2) HUD may provide...

  15. OMEGA time transmissions and receiver design.

    NASA Technical Reports Server (NTRS)

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

    1972-01-01

    This document gives a short history of the development of dual VLF time-transmission technique. 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, a prototype OMEGA timing receiving design is described.

  16. Heat receivers for solar dynamic space power systems

    NASA Astrophysics Data System (ADS)

    Perez-Davis, Marla Esther

    A review of state-of-the-art technology is presented and discussed for phase change materials. Some of the advanced solar dynamic designs developed as part of the Advanced Heat Receiver Conceptual Design Study performed for LeRC are discussed. The heat receivers are analyzed and several recommendations are proposed, including two new concepts. The first concept evaluated the effect of tube geometries inside the heat receiver. It was found that a triangular configuration would provide better heat transfer to the working fluid, although not necessarily with a reduction in receiver size. A sensible heat receiver considered in this study uses vapor grown graphite fiber-carbon (VGCF/C) composite as the thermal storage media and was designed for a 7 kW Brayton engine. The proposed heat receiver stores the required energy to power the system during eclipse in the VGCF/C composite. The heat receiver analysis was conducted through the Systems Improved Numerical Differencing Analyzer and Fluid Integrator (SINDA) software package. The proposed heat receiver compares well with other latent and advanced sensible heat receivers while avoiding the problems associated with latent heat storage salts and liquid metal heat pipes. The weight and size of the system can be optimized by changes in geometry and technology advances for this new material. In addition to the new concepts, the effect of atomic oxygen on several materials is reviewed. A test was conducted for atomic oxygen attack on boron nitride, which experienced a negligible mass loss when exposed to an atomic oxygen fluence of 5 x 10 exp 21 atoms/sq cm. This material could be used to substitute the graphite aperture plate of the heat receiver.

  17. A 30-GHz monolithic receiver

    NASA Technical Reports Server (NTRS)

    Liu, Louis C. T.; Liu, Carol S.; Kessler, Joel R.; Wang, Shing-Kuo; Chang, Ching-Der

    1986-01-01

    Several monolithic integrated circuits have been developed to make a 30-GHz receiver. The receiver components include a low-noise amplifier (LNA), an IF amplifier, a mixer, and a phase shifter. The LNA has a 7-dB noise figure with over 17 dB of associated gain. The IF amplifier has a 13-dB gain with a 30-dB control range. The mixer has a conversion loss of 10.5 dB. The phase shifter has a 180-deg phase shift control and a minimum insertion loss of 1.6 dB.

  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. A Novel Multi-Receiver Signcryption Scheme with Complete Anonymity.

    PubMed

    Pang, Liaojun; Yan, Xuxia; Zhao, Huiyang; Hu, Yufei; Li, Huixian

    2016-01-01

    Anonymity, which is more and more important to multi-receiver schemes, has been taken into consideration by many researchers recently. To protect the receiver anonymity, in 2010, the first multi-receiver scheme based on the Lagrange interpolating polynomial was proposed. To ensure the sender's anonymity, the concept of the ring signature was proposed in 2005, but afterwards, this scheme was proven to has some weakness and at the same time, a completely anonymous multi-receiver signcryption scheme is proposed. In this completely anonymous scheme, the sender anonymity is achieved by improving the ring signature, and the receiver anonymity is achieved by also using the Lagrange interpolating polynomial. Unfortunately, the Lagrange interpolation method was proven a failure to protect the anonymity of receivers, because each authorized receiver could judge whether anyone else is authorized or not. Therefore, the completely anonymous multi-receiver signcryption mentioned above can only protect the sender anonymity. In this paper, we propose a new completely anonymous multi-receiver signcryption scheme with a new polynomial technology used to replace the Lagrange interpolating polynomial, which can mix the identity information of receivers to save it as a ciphertext element and prevent the authorized receivers from verifying others. With the receiver anonymity, the proposed scheme also owns the anonymity of the sender at the same time. Meanwhile, the decryption fairness and public verification are also provided.

  20. Spread Spectrum Receiver Electromagnetic Interference (EMI) Test Guide

    NASA Technical Reports Server (NTRS)

    Wheeler, Mark L.

    1998-01-01

    This program consisted of: (1) a study to define appropriate EMI test guidelines and test methods for direct sequence (DS) spread spectrum receivers; and (2) preparation of a written test guide to document the recommended test methods. The scope of this test guide includes: (1) a discussion of generic DS receiver performance characteristics; (2) a summary of S-band TDRSS receiver operation; (3) a discussion of DS receiver EMI susceptibility mechanisms and characteristics; (4) a summary of military standard test guidelines; (5) recommended test approach and methods; and (6) general conclusions and recommendations for future studies in the area of spread spectrum receiver testing.

  1. Unprecented syntonization and syncronization accuracy via simultaneous viewing with GPS receivers: Construction characteristics of an NBS/GPS receiver

    NASA Technical Reports Server (NTRS)

    Davis, D. D.; Weiss, M.; Clements, A.; Allan, D. W.

    1982-01-01

    The National Bureau of Standards/Global Positioning System (NBS/GPS) receiver is discussed. It is designed around the concept of obtaining high accuracy, low cost time and frequency comparisons between remote frequency standards and clocks with the intent to aid international time and frequency coordination. Preliminary tests of this comparison technique between Boulder, CO and Washington, D.C indicate the ability to do accurate time transfer to better that 10 ns, and frequency measurements to better than 1 part in 10 to the 14th power. The hardware and software of the receiver is detailed. The receiver is fully automatic with a built-in 0.1 ns resolution time interval counter. A microprocessor does data processing. Satellite signal stabilities are routinely at the 5 ns level for 15 s averages, and the internal receiver stabilities are at the 1 ns level.

  2. 47 CFR 15.117 - TV broadcast receivers.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... service on the frequencies allocated for broadcast television service. (j) For a TV broadcast receiver... prominently display in close proximity to the images or descriptions of such television broadcast receivers...

  3. 47 CFR 15.117 - TV broadcast receivers.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... service on the frequencies allocated for broadcast television service. (j) For a TV broadcast receiver... prominently display in close proximity to the images or descriptions of such television broadcast receivers...

  4. Advanced Receiver For Phase-Shift-Keyed Signals

    NASA Technical Reports Server (NTRS)

    Hinedi, Sami M.

    1992-01-01

    ARX II is second "breadboard" version of advanced receiver, a hybrid digital/analog receiving subsystem, extracting symbols and Doppler shifts from weak phase-shift-keyed signals. Useful in terrestrial digital communication systems.

  5. 47 CFR 15.117 - TV broadcast receivers.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... receive TV service on the frequencies allocated for broadcast television service. (j) For a TV broadcast... in close proximity to the images or descriptions of such television broadcast receivers, in clear and...

  6. 47 CFR 15.117 - TV broadcast receivers.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... receive TV service on the frequencies allocated for broadcast television service. (j) For a TV broadcast... in close proximity to the images or descriptions of such television broadcast receivers, in clear and...

  7. 47 CFR 15.117 - TV broadcast receivers.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... receive TV service on the frequencies allocated for broadcast television service. (j) For a TV broadcast... in close proximity to the images or descriptions of such television broadcast receivers, in clear and...

  8. 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.

  9. 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.

  10. 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.

  11. Precision Continuum Receivers for Astrophysical Applications

    NASA Technical Reports Server (NTRS)

    Wollack, Edward J.

    2011-01-01

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

  12. 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.

  13. Which patients receive advice on diet and exercise? Do certain characteristics affect whether they receive such advice?

    PubMed

    Sinclair, Jennifer; Lawson, Beverley; Burge, Fred

    2008-03-01

    To examine whether patients' characteristics, familiarity with the clinic, or perspectives on the quality of their care predict whether they receive advice from physicians regarding diet and exercise. Secondary data analysis of responses to the Primary Care Practice Survey. Capital District Health Authority in Nova Scotia. Residents of the Capital District Health Authority 18 years old and older (N = 1562). Percentage of patients who reported frequently receiving advice from their family physicians regarding diet and exercise. Almost 38% of respondents reported frequently receiving advice from their physicians on diet. Those more likely to receive advice on diet were male (adjusted odds ratio [AOR] 1.6, 95% confidence interval [CI] 1.2 to 2.1), were 35 to 54 years old (compared with those aged 18 to 34) (AOR 1.5, 95% CI 1.1 to 2.2), had more chronic illnesses (AOR 1.3, 95% CI 1.2 to 1.6), had good relationships with their health care providers (AOR 2.3, 95% CI 1.8 to 3.1), or reported higher scores on an enablement scale (AOR 2.2, 95% CI 1.6 to 3.1). Respondents who reported their health status as excellent were less likely to receive advice on diet (AOR 0.5, 95% CI 0.3 to 0.9). About 42% of respondents reported frequently receiving advice on exercise. Men (AOR 1.7, 95% CI 1.3 to 2.2), those older than 35 years (AOR 1.7, 95% CI 1.2 to 2.4 for those aged 35 to 54; AOR 1.6, 95% CI 1.1 to 2.3 for those 55 and older), those rating their health as good (AOR 1.6, 95% CI 1.1 to 2.4), those with more chronic illnesses (AOR 1.3, 95% CI 1.1 to 1.5), and those reporting higher scores on communication (AOR 3.2, 95% CI 2.3 to 4.4) and enablement (AOR 1.8, 95% CI 1.3 to 2.4) scales were more likely to receive advice on exercise. Strategies to increase the number of patients who receive advice on diet and exercise would likely include enhancing communication between patients and their physicians, improving relationships between patients and their physicians, and improving

  14. 49 CFR 220.33 - Receiving a radio transmission.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION RAILROAD COMMUNICATIONS Radio and Wireless Communication Procedures § 220.33 Receiving a radio transmission. (a) Upon receiving a radio call, an employee shall promptly... 49 Transportation 4 2013-10-01 2013-10-01 false Receiving a radio transmission. 220.33 Section 220...

  15. 49 CFR 220.33 - Receiving a radio transmission.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION RAILROAD COMMUNICATIONS Radio and Wireless Communication Procedures § 220.33 Receiving a radio transmission. (a) Upon receiving a radio call, an employee shall promptly... 49 Transportation 4 2014-10-01 2014-10-01 false Receiving a radio transmission. 220.33 Section 220...

  16. Hematologic and Selected Hepatic Changes Produced by Substituted p-Bensoquinones in the Rat.

    DTIC Science & Technology

    1980-07-01

    DIVISION OF NUTRITION TECHNOLOGY *DIVISION OF CUTANEOUS HAZARDS I LEECE D IBAI7 TA EMENl AU I __ b rouleISO, Ca. JULYV 1980 CD, LA. 9=3TIRMAN ARMY...jaundice, anemia, hemoglobinuria, and cachexia (8). In previous studies, we found that benzoquinone tox- icity in rats resulted in respiratory depression...randomly housed in stainless steel wire-bottomed cages, one to a cage, and fed a stock diet (Rodent Laboratory Chow #5001, Ralston Purina Co., St. Louis

  17. Receiver subsystem analysis report (RADL Item 4-1). The 10-MWe solar thermal central-receiver pilot plant: Solar-facilities design integration

    NASA Astrophysics Data System (ADS)

    1982-04-01

    The results of thermal hydraulic, design for the stress analyses which are required to demonstrate that the receiver design for the Barstow Solar Pilot Plant satisfies the general design and performance requirements during the plant's design life are presented. Recommendations are made for receiver operation. The analyses are limited to receiver subsystem major structural parts (primary tower, receiver unit core support structure), pressure parts (absorber panels, feedwater, condensate and steam piping/components, flash tank, and steam mainfold) and shielding.

  18. Advanced sensible heat solar receiver for space power

    NASA Technical Reports Server (NTRS)

    Bennett, Timothy J.; Lacy, Dovie E.

    1988-01-01

    NASA Lewis, through in-house efforts, has begun a study to generate a conceptual design of a sensible heat solar receiver and to determine the feasibility of such a system for space power applications. The sensible heat solar receiver generated in this study uses pure lithium as the thermal storage medium and was designed for a 7 kWe Brayton (PCS) operating at 1100 K. The receiver consists of two stages interconnected via temperature sensing variable conductance sodium heat pipes. The lithium is contained within a niobium vessel and the outer shell of the receiver is constructed of third generation rigid, fibrous ceramic insulation material. Reradiation losses are controlled with niobium and aluminum shields. By nature of design, the sensible heat receiver generated in this study is comparable in both size and mass to a latent heat system of similar thermal capacitance. The heat receiver design and thermal analysis was conducted through the combined use of PATRAN, SINDA, TRASYS, and NASTRAN software packages.

  19. Advanced sensible heat solar receiver for space power

    NASA Technical Reports Server (NTRS)

    Bennett, Timothy J.; Lacy, Dovie E.

    1988-01-01

    NASA Lewis, through in-house efforts, has begun a study to generate a conceptual design of a sensible heat solar receiver and to determine the feasibility of such a system for space power applications. The sensible heat solar receiver generated in this study uses pure lithium as the thermal storage medium and was designed for a 7 kWe Brayton (PCS) operating at 1100 K. The receiver consists of two stages interconnected via temperature sensing variable conductance sodium heat pipes. The lithium is contained within a niobium vessel and the outer shell of the receiver is constructed of third generation rigid, fibrous ceramic insulation material. Reradiation losses are controlled with niobium and aluminum shields. By nature of design, the sensible heat receiver generated in this study is comparable in both size and mass to a latent heat system of similar thermal capacitance. The heat receiver design and thermal analysis were conducted through the combined use of PATRAN, SINDA, TRASYS, and NASTRAN software packages.

  20. Communications/Electronics Receiver Performance Degradation Handbook (Second Edition)

    DTIC Science & Technology

    1975-08-01

    receiver to another in the Rf and IF filter characteristics modify the transfer of inter- forence power through the receiver to the IF output, and so the...modulation system the transmitted and received messages arce in general different bemaus* of small inte, forence or noise perturbations. The probability of

  1. FFT analysis of sensible-heat solar-dynamic receivers

    NASA Astrophysics Data System (ADS)

    Lund, Kurt O.

    The use of solar dynamic receivers with sensible energy storage in single-phase materials is considered. The feasibility of single-phase designs with weight and thermal performance comparable to existing two-phase designs is addressed. Linearized heat transfer equations are formulated for the receiver heat storage, representing the periodic input solar flux as the sum of steady and oscillating distributions. The steady component is solved analytically to produce the desired receiver steady outlet gas temperature, and the FFT algorithm is applied to the oscillating components to obtain the amplitudes and mode shapes of the oscillating solid and gas temperatures. The results indicate that sensible-heat receiver designs with performance comparable to state-of-the-art two-phase receivers are available.

  2. Spread Spectrum Receiver Electromagnetic Interference (EMI) Test Guide

    NASA Technical Reports Server (NTRS)

    Wheeler, M. L.

    1998-01-01

    The objective of this test guide is to document appropriate unit level test methods and techniques for the performance of EMI testing of Direct Sequence (DS) spread spectrum receivers. Consideration of EMI test methods tailored for spread spectrum receivers utilizing frequency spreading, techniques other than direct sequence (such as frequency hopping, frequency chirping, and various hybrid methods) is beyond the scope of this test guide development program and is not addressed as part of this document EMI test requirements for NASA programs are primarily developed based on the requirements contained in MIL-STD-46 1 D (or earlier revisions of MIL-STD-46 1). The corresponding test method guidelines for the MIL-STD-461 D tests are provided in MIL-STD-462D. These test methods are well documented with the exception of the receiver antenna port susceptibility tests (intermodulation, cross modulation, and rejection of undesired signals) which must be tailored to the specific type of receiver that is being tested. Thus, test methods addressed in this guide consist only of antenna port tests designed to evaluate receiver susceptibility characteristics. MIL-STD-462D should be referred for guidance pertaining to test methods for EMI tests other than the antenna port tests. The scope of this test guide includes: (1) a discussion of generic DS receiver performance characteristics; (2) a summary of S-band TDRSS receiver operation; (3) a discussion of DS receiver EMI susceptibility mechanisms and characteristics; (4) a summary of military standard test guidelines; (5) recommended test approach and methods; and (6) general conclusions and recommendations for future studies in the area of spread spectrum receiver testing.

  3. Photonic compressed sensing nyquist folding receiver

    DTIC Science & Technology

    2017-09-01

    filter . Two independent photonic receiver architectures are designed and analyzed over the course of this research. Both receiver designs are...undersamples the signals using an opti- cal modulator configuration at 1550 nm and collects the detected samples in a low pass interpolation filter ...Electronic Intelligence EW Electronic Warfare FM Frequency Modulated LNA Low Noise Amplifier LPF Low Pass Filter MZI Mach-Zehnder Interferometer NYFR Nyquist

  4. Calibration of the BEV GPS Receiver by Using TWSTFT

    DTIC Science & Technology

    2008-12-01

    40th Annual Precise Time and Time Interval (PTTI) Meeting 543 CALIBRATION OF THE BEV GPS RECEIVER BY USING TWSTFT A. Niessner1, W...a calibration of the BEV reference GPS time receiver by using Two-way Satellite Time and Frequency Transfer ( TWSTFT ). Due to antenna changes, a new...calibration of the BEV receiver was necessary. This receiver is the first GPS receiver with calibration through TWSTFT and used for UTC computation

  5. 49 CFR 220.33 - Receiving a radio transmission.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... § 220.33 Receiving a radio transmission. (a) Upon receiving a radio call, an employee shall promptly acknowledge the call, identifying the employee's station in accordance with the requirements of § 220.27 and... with other immediate duties relating to the safety of railroad operations. (b) An employee who receives...

  6. 49 CFR 220.33 - Receiving a radio transmission.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... § 220.33 Receiving a radio transmission. (a) Upon receiving a radio call, an employee shall promptly acknowledge the call, identifying the employee's station in accordance with the requirements of § 220.27 and... with other immediate duties relating to the safety of railroad operations. (b) An employee who receives...

  7. 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.

  8. 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.

  9. Estimating Total Electron Content Using 1,000+ GPS Receivers

    NASA Technical Reports Server (NTRS)

    Komjathy, Attila; Mannucci, Anthony

    2006-01-01

    A computer program uses data from more than 1,000 Global Positioning System (GPS) receivers in an Internet-accessible global network to generate daily estimates of the global distribution of vertical total electron content (VTEC) of the ionosphere. This program supersedes an older program capable of processing readings from only about 200 GPS receivers. This program downloads the data via the Internet, then processes the data in three stages. In the first stage, raw data from a global subnetwork of about 200 receivers are preprocessed, station by station, in a Kalman-filter-based least-squares estimation scheme that estimates satellite and receiver differential biases for these receivers and for satellites. In the second stage, an observation equation that incorporates the results from the first stage and the raw data from the remaining 800 receivers is solved to obtain the differential biases for these receivers. The only remaining error sources for which an account cannot be given are multipath and receiver noise contributions. The third stage is a postprocessing stage in which all the processed data are combined and used to generate new data products, including receiver differential biases and global and regional VTEC maps and animations.

  10. Fabrication and installation of the Solar Two central receiver

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Litwin, R.Z.; Rogers, R.D.

    The heart of the Solar Two power plant is the molten salt central receiver that has been designed, fabricated, and installed over an 18 month schedule. During this time, the receiver system from Solar One was also completely disassembled and removed. The receiver tower structure, for the most part, was left intact because Solar Two was designed to fit this structure such that construction time and costs could be minimized. In order to meet this aggressive schedule, receiver panel fabrication required the parallel production of many components. The sequence for assembly of the four major receiver panel components (i.e., tubes,more » header assembly, strongback, and header oven covers) and key fabrication activities such as welding are described. Once the receiver panels were complete, their installation at the site was begun, and the order in which receiver system components were installed in the tower is described. The completion of the Solar Two receiver proved the fabricability of this important system. However, successful operation of the system at Solar Two is needed to demonstrate the technical feasibility of the molten salt central receiver concept.« less

  11. Receiver-Coupling Schemes Based On Optimal-Estimation Theory

    NASA Technical Reports Server (NTRS)

    Kumar, Rajendra

    1992-01-01

    Two schemes for reception of weak radio signals conveying digital data via phase modulation provide for mutual coupling of multiple receivers, and coherent combination of outputs of receivers. In both schemes, optimal mutual-coupling weights computed according to Kalman-filter theory, but differ in manner of transmission and combination of outputs of receivers.

  12. 10 CFR 733.5 - Allegations received by DOE.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false Allegations received by DOE. 733.5 Section 733.5 Energy DEPARTMENT OF ENERGY ALLEGATIONS OF RESEARCH MISCONDUCT § 733.5 Allegations received by DOE. If DOE receives directly a written allegation of research misconduct with regard to research under a DOE contract or...

  13. 10 CFR 733.5 - Allegations received by DOE.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 4 2011-01-01 2011-01-01 false Allegations received by DOE. 733.5 Section 733.5 Energy DEPARTMENT OF ENERGY ALLEGATIONS OF RESEARCH MISCONDUCT § 733.5 Allegations received by DOE. If DOE receives directly a written allegation of research misconduct with regard to research under a DOE contract or...

  14. 10 CFR 733.5 - Allegations received by DOE.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 4 2012-01-01 2012-01-01 false Allegations received by DOE. 733.5 Section 733.5 Energy DEPARTMENT OF ENERGY ALLEGATIONS OF RESEARCH MISCONDUCT § 733.5 Allegations received by DOE. If DOE receives directly a written allegation of research misconduct with regard to research under a DOE contract or...

  15. 10 CFR 733.5 - Allegations received by DOE.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 4 2013-01-01 2013-01-01 false Allegations received by DOE. 733.5 Section 733.5 Energy DEPARTMENT OF ENERGY ALLEGATIONS OF RESEARCH MISCONDUCT § 733.5 Allegations received by DOE. If DOE receives directly a written allegation of research misconduct with regard to research under a DOE contract or...

  16. 10 CFR 733.5 - Allegations received by DOE.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 4 2014-01-01 2014-01-01 false Allegations received by DOE. 733.5 Section 733.5 Energy DEPARTMENT OF ENERGY ALLEGATIONS OF RESEARCH MISCONDUCT § 733.5 Allegations received by DOE. If DOE receives directly a written allegation of research misconduct with regard to research under a DOE contract or...

  17. 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.

  18. GPU Acceleration of DSP for Communication Receivers.

    PubMed

    Gunther, Jake; Gunther, Hyrum; Moon, Todd

    2017-09-01

    Graphics processing unit (GPU) implementations of signal processing algorithms can outperform CPU-based implementations. This paper describes the GPU implementation of several algorithms encountered in a wide range of high-data rate communication receivers including filters, multirate filters, numerically controlled oscillators, and multi-stage digital down converters. These structures are tested by processing the 20 MHz wide FM radio band (88-108 MHz). Two receiver structures are explored: a single channel receiver and a filter bank channelizer. Both run in real time on NVIDIA GeForce GTX 1080 graphics card.

  19. Progress in integrated-circuit horn antennas for receiver applications. Part 2: A 90 GHz quasi-integrated horn antenna receiver

    NASA Technical Reports Server (NTRS)

    Ali-Ahmad, Walid Y.; Eleftheriades, George V.; Rebeiz, Gabriel M.

    1992-01-01

    A receiver belonging to the family of integrated planar receivers has been developed at 90 GHz. It consists of a planar Schottky-diode placed at the feed of a dipole-probe suspended inside an integrated horn antenna. The measured planar mixer single-sideband conversion loss at 91.2 GHz (LO) with a 200 MHz IF frequency is 8.3dB plus or minus 0.3dB. The low cost of fabrication and simplicity of this design makes it ideal for millimeter and submillimeter-wave receivers.

  20. 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.

  1. 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.

  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. Integrated Cryogenic Satellite Communications Cross-Link Receiver Experiment

    NASA Technical Reports Server (NTRS)

    Romanofsky, R. R.; Bhasin, K. B.; Downey, A. N.; Jackson, C. J.; Silver, A. H.; Javadi, H. H. S.

    1995-01-01

    An experiment has been devised which will validate, in space, a miniature, high-performance receiver. The receiver blends three complementary technologies; high temperature superconductivity (HTS), pseudomorphic high electron mobility transistor (PHEMT) monolithic microwave integrated circuits (MMIC), and a miniature pulse tube cryogenic cooler. Specifically, an HTS band pass filter, InP MMIC low noise amplifier, HTS-sapphire resonator stabilized local oscillator (LO), and a miniature pulse tube cooler will be integrated into a complete 20 GHz receiver downconverter. This cooled downconverter will be interfaced with customized signal processing electronics and integrated onto the space shuttle's 'HitchHiker' carrier. A pseudorandom data sequence will be transmitted to the receiver, which is in low Earth orbit (LEO), via the Advanced Communication Technology Satellite (ACTS) on a 20 GHz carrier. The modulation format is QPSK and the data rate is 2.048 Mbps. The bit error rate (BER) will be measured in situ. The receiver is also equipped with a radiometer mode so that experiment success is not totally contingent upon the BER measurement. In this mode, the receiver uses the Earth and deep space as a hot and cold calibration source, respectively. The experiment closely simulates an actual cross-link scenario. Since the receiver performance depends on channel conditions, its true characteristics would be masked in a terrestrial measurement by atmospheric absorption and background radiation. Furthermore, the receiver's performance depends on its physical temperature, which is a sensitive function of platform environment, thermal design, and cryocooler performance. This empirical data is important for building confidence in the technology.

  4. 47 CFR 95.27 - Paging receiver description.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... receiver is a unit capable of receiving the radio signals from a base station for the bearer to hear a page (someone's name or other identifier said in order to find, summon or notify him/her) spoken by the base station operator. ...

  5. 48 CFR 1846.672-7 - Receiving instructions.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 6 2010-10-01 2010-10-01 true Receiving instructions. 1846.672-7 Section 1846.672-7 Federal Acquisition Regulations System NATIONAL AERONAUTICS AND SPACE ADMINISTRATION CONTRACT MANAGEMENT QUALITY ASSURANCE Material Inspection and Receiving Reports 1846.672-7...

  6. Flexible All-Digital Receiver for Bandwidth Efficient Modulations

    NASA Technical Reports Server (NTRS)

    Gray, Andrew; Srinivasan, Meera; Simon, Marvin; Yan, Tsun-Yee

    2000-01-01

    An all-digital high data rate parallel receiver architecture developed jointly by Goddard Space Flight Center and the Jet Propulsion Laboratory is presented. This receiver utilizes only a small number of high speed components along with a majority of lower speed components operating in a parallel frequency domain structure implementable in CMOS, and can currently process up to 600 Mbps with standard QPSK modulation. Performance results for this receiver for bandwidth efficient QPSK modulation schemes such as square-root raised cosine pulse shaped QPSK and Feher's patented QPSK are presented, demonstrating the flexibility of the receiver architecture.

  7. Signal-processing theory for the TurboRogue receiver

    NASA Technical Reports Server (NTRS)

    Thomas, J. B.

    1995-01-01

    Signal-processing theory for the TurboRogue receiver is presented. The signal form is traced from its formation at the GPS satellite, to the receiver antenna, and then through the various stages of the receiver, including extraction of phase and delay. The analysis treats the effects of ionosphere, troposphere, signal quantization, receiver components, and system noise, covering processing in both the 'code mode' when the P code is not encrypted and in the 'P-codeless mode' when the P code is encrypted. As a possible future improvement to the current analog front end, an example of a highly digital front end is analyzed.

  8. Advances in central receivers for concentrating solar applications

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ho, Clifford K.

    This paper provides a review of current state-of-the-art commercial central receiver systems and emerging technologies intended to increase the outlet temperature to >700 °C. Research on particle-based, gas-based, and liquid-based receiver designs that can achieve these higher temperatures are discussed. Particle-based technologies include directly irradiated designs (free-falling, obstructed, centrifugal) and enclosed designs (gravity fed, fluidized). New gas-based receivers include micro-channel designs and light-trapping configurations that increase the surface area, heat transfer, and solar absorptance to enable higher fluxes and pressures. Liquid-based receivers and materials that are reviewed include high-temperature halide salts (chlorides and fluorides), carbonate salts, and liquid metals (sodiummore » and lead bismuth). Advantages and challenges associated with each of the technologies and receiver designs are presented.« less

  9. Advances in central receivers for concentrating solar applications

    DOE PAGES

    Ho, Clifford K.

    2017-04-09

    This paper provides a review of current state-of-the-art commercial central receiver systems and emerging technologies intended to increase the outlet temperature to >700 °C. Research on particle-based, gas-based, and liquid-based receiver designs that can achieve these higher temperatures are discussed. Particle-based technologies include directly irradiated designs (free-falling, obstructed, centrifugal) and enclosed designs (gravity fed, fluidized). New gas-based receivers include micro-channel designs and light-trapping configurations that increase the surface area, heat transfer, and solar absorptance to enable higher fluxes and pressures. Liquid-based receivers and materials that are reviewed include high-temperature halide salts (chlorides and fluorides), carbonate salts, and liquid metals (sodiummore » and lead bismuth). Advantages and challenges associated with each of the technologies and receiver designs are presented.« less

  10. Digital coherent receiver based transmitter penalty characterization.

    PubMed

    Geisler, David J; Kaufmann, John E

    2016-12-26

    For optical communications links where receivers are signal-power-starved, such as through free-space, it is important to design transmitters and receivers that can operate as close as practically possible to theoretical limits. A total system penalty is typically assessed in terms of how far the end-to-end bit-error rate (BER) is from these limits. It is desirable, but usually difficult, to determine the division of this penalty between the transmitter and receiver. This paper describes a new rigorous and computationally based method that isolates which portion of the penalty can be assessed against the transmitter. There are two basic parts to this approach: (1) use of a coherent optical receiver to perform frequency down-conversion of a transmitter's optical signal waveform to the electrical domain, preserving both optical field amplitude and phase information, and (2): software-based analysis of the digitized electrical waveform. The result is a single numerical metric that quantifies how close a transmitter's signal waveform is to the ideal, based on its BER performance with a perfect software-defined matched-filter receiver demodulator. A detailed description of applying the proposed methodology to the waveform characterization of an optical burst-mode differential phase-shifted keying (DPSK) transmitter is experimentally demonstrated.

  11. 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.

  12. Perception of Non-surgical Periodontal Treatment in Individuals Receiving or Not Receiving Local Anaesthesia.

    PubMed

    Leung, W Keung; Duan, Yi Ran; Dong, Xiao Xiao; Yeung, Kim Wai Shadow; Zhou, Shuang Ying; Corbet, Esmonde F; Meng, Huan Xin

    2016-01-01

    Patients might refuse the offer of local anaesthesia (LA) administration prior to dental treatment. This study investigates subjective discomfort perception during non-surgical mechanical periodontal therapy delivered with or without LA. Sixty patients with mild to moderate chronic periodontitis and prior periodontal debridement experience were randomly enrolled in nonsurgical therapy of a quadrant with or without LA administration. Patients were free to comply or not with the allocated LA arrangement. Visual analogue scales (VAS) of discomfort perception at various stages of the treatment as well as overall satisfaction were recorded. Demographic, psychosocial and periodontal parameters were recorded. Thirty-one patients undergoing nonsurgical periodontal therapy not receiving (LA-) and 29 participants receiving LA (LA+) were studied. Compared to LA- patients, LA+ individuals perceived less discomfort during treatment and reported less dental anxiety (p<0.05). Lower overall treatment satisfaction was associated with prior unpleasant periodontal experience (p=0.047). Overall, debridement discomfort was associated with not receiving LA, noncompliance with the pain control regimen allocated, longer treatment duration, greater gingival inflammation and a higher percentage sites with probing pocket depths≥5 mm (p<0.05). Clinicians should be aware that patients who refuse LA can experience higher dental anxiety and therefore may require various pain control strategies for comfort during nonsurgical periodontal therapy, which, if not employed, can lead to less periodontal treatment satisfaction.

  13. Analysis of Optimum Heterodyne Receivers for Coherent Lidar Applications

    NASA Technical Reports Server (NTRS)

    Amzajerdian, Farzin

    2002-01-01

    A full analysis of the combined effects of all the noise sources of optical heterodyne receiver and the interaction between the competing control parameters of the receiver detector and pre-amplifier will be presented. This analysis provides the mean for true optimization of the coherent lidar receiver. The significance of the optimization of heterodyne receiver is shown for 2-micron coherent lidar.

  14. Radiant energy receiver having improved coolant flow control means

    DOEpatents

    Hinterberger, H.

    1980-10-29

    An improved coolant flow control for use in radiant energy receivers of the type having parallel flow paths is disclosed. A coolant performs as a temperature dependent valve means, increasing flow in the warmer flow paths of the receiver, and impeding flow in the cooler paths of the receiver. The coolant has a negative temperature coefficient of viscosity which is high enough such that only an insignificant flow through the receiver is experienced at the minimum operating temperature of the receiver, and such that a maximum flow is experienced at the maximum operating temperature of the receiver. The valving is accomplished by changes in viscosity of the coolant in response to the coolant being heated and cooled. No remotely operated valves, comparators or the like are needed.

  15. 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.

  16. Campus Projects Receiving "Earmarks."

    ERIC Educational Resources Information Center

    Schonberger, Benjamin

    1991-01-01

    Specific campus projects that Congress has directed federal agencies to support this year at over 120 colleges and universities are listed. The agencies neither requested support nor sponsored merit-based competitions for the awards. In some cases, the institutions have a history of receiving special federal treatment. (MSE)

  17. Mentally disordered women in jail: who receives services?

    PubMed Central

    Teplin, L A; Abram, K M; McClelland, G M

    1997-01-01

    OBJECTIVES: Many jail inmates have severe psychiatric disorders (e.g., schizophrenia, major affective disorders). The courts have mandated that detainees have a constitutional right to treatment. We investigated what proportion of female jail detainees needed mental health services, what proportion received services, and what variables predicted who received services. METHODS: Trained interviewers administered a psychiatric evaluation (the NIMH Diagnostic Interview Schedule) to 1272 randomly selected female jail detainees during jail intake in a large Midwestern city. Project staff then documented whether women subsequently received services, using records and case files. RESULTS: Of the women who needed services, 23.5% received them while they were in jail. Type of disorder, treatment history, and socio-demographic variables all affected the odds of a mentally ill woman's receiving services. CONCLUSIONS: Correctional health care is a growing national public health problem. The magnitude of mental health service needs far exceeds current resources. PMID:9146439

  18. Achieving excellence in the management of accounts receivable.

    PubMed

    Ladewig, T L; Hecht, B A

    1993-09-01

    Recent changes in healthcare reimbursement rules and practices have made the task of accounts receivable management a particularly demanding one for most financial managers. One multihospital system, after pursuing numerous strategies to reduce its accounts receivable with only marginal levels of success, launched a systemwide initiative to share both the positive and the negative accounts receivable management experiences of each department at each hospital in the system with all patient accounting staff. The objective of the initiative was to use the lessons learned from those experiences to attain excellence in accounts receivable management throughout the system. The ultimate success of the initiative is detailed in the following article.

  19. 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.

  20. Design of simplified maximum-likelihood receivers for multiuser CPM systems.

    PubMed

    Bing, Li; Bai, Baoming

    2014-01-01

    A class of simplified maximum-likelihood receivers designed for continuous phase modulation based multiuser systems is proposed. The presented receiver is built upon a front end employing mismatched filters and a maximum-likelihood detector defined in a low-dimensional signal space. The performance of the proposed receivers is analyzed and compared to some existing receivers. Some schemes are designed to implement the proposed receivers and to reveal the roles of different system parameters. Analysis and numerical results show that the proposed receivers can approach the optimum multiuser receivers with significantly (even exponentially in some cases) reduced complexity and marginal performance degradation.

  1. Selected accounts receivable performance statistics for radiology practices: an analysis of the adjusted collection percentage and days charges in accounts receivable.

    PubMed

    Cergnul, John J; Russell, Philip J; Sunshine, Jonathan H

    2005-12-01

    To provide comparative data and analysis with respect to accounts receivable management performance criteria. Data from 3 sources were analyzed: the Radiology Business Management Association's (RBMA) 2003 Accounts Receivable Performance Survey; the RBMA's 2003 Accounts Receivable Survey; and Hogan and Sunshine's 2004 Radiology article "Financial Ratios in Diagnostic Radiology Practices: Variability and Trends," the data for which were drawn primarily from the ACR's 1999 Survey of Practices. The RBMA surveyed (via e-mail and postal mail) only its members, with response rates of 15% and 9%, respectively. The ACR's survey response rate was 66%, via postal mail, and was distributed without regard to the RBMA membership status of the practice manager or even whether the practice employed a practice manager. Comparison among the survey results provided information on trends. Median practice professional component adjusted collection percentage (ACP) deteriorated from 87.3% to 85.1% between the RBMA surveys. Practices limited to global fee billing faired much better when performing their billing in house, as opposed to using a billing service, with mean ACPs of 91.2% and 79.4%, respectively. Days charges in accounts receivable 2004 mean results for professional component billing and global fee billing were nearly identical at 56.11 and 55.54 days, respectively. The 2003 RBMA survey reported 63.74 days for professional component billing and 77.33 days for global fee billing. The improvement from 2003 to 2004 was highly significant for both professional component billing and global fee billing. The 2004 RBMA survey also reflected a rather dramatic improvement in days charges in accounts receivable compared with Hogan and Sunshine's results, which showed a mean of 69 days charges in accounts receivable. The conflicting trends between ACP performance and days charges in accounts receivable performance may be explained by the increasing sophistication of accounts receivable

  2. Improved noise-adding radiometer for microwave receivers

    NASA Technical Reports Server (NTRS)

    Batelaan, P. D.; Stelzried, C. T.; Goldstein, R. M.

    1973-01-01

    Use of input switch and noise reference standard is avoided by using noise-adding technique. Excess noise from solid state noise-diode is coupled into receiver through directional coupler and square-wave modulated at low rate. High sensitivity receivers for radioastronomy applications are utilized with greater confidence in stability of radiometer.

  3. Miniature Low-Noise G-Band I-Q Receiver

    NASA Technical Reports Server (NTRS)

    Kangaslahti, Pekka P.; Pukala, David M.; Gaier, Todd C.; Tanner, Alan B.; O'Dwyer, Ian J.; Lambrigtsen, Bjom H.; Soria, Mary M.; Owen, Heather R.; Lai, Richard; Mei, Xiaobing

    2010-01-01

    Weather forecasting, hurricane tracking, and atmospheric science applications depend on humidity sounding of atmosphere. Current instruments provide these measurements from groundbased, airborne, and low Earth orbit (LEO) satellites by measuring radiometric temperature on the flanks of the 183-GHz water vapor line. Miniature, low-noise receivers have been designed that will enable these measurements from a geostationary, thinned array sounder, which is based on hundreds of low-noise receivers that convert the 180-GHz signal directly to baseband in-phase and in-quadrature signals for digitization and correlation. The developed receivers provide a noise temperature of 450 K from 165 to 183 GHz (NF = 4.1 dB), and have a mass of 3 g while consuming 24 mW of power. These are the most sensitive broadband I-Q receivers at this frequency range that operate at room temperature, and are significantly lower in mass and power consumption than previously reported receivers.

  4. Ultrabroadband Phased-Array Receivers Based on Optical Techniques

    DTIC Science & Technology

    2016-02-26

    AFRL-AFOSR-VA-TR-2016-0121 Ultrabroadband Phased- array Receivers Based on Optical Techniques Christopher Schuetz UNIVERSITY OF DELAWARE Final Report...Jul 15 4. TITLE AND SUBTITLE Ultrabroadband Phased- Array Receivers Based on Optical Techniques 5a. CONTRACT NUMBER 5b. GRANT NUMBER FA9550-12-1...receiver that enables us to capture and convert signals across an array using photonic modulators, routing these signals to a central location using

  5. 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.

  6. Towards Self-Clocked Gated OCDMA Receiver

    NASA Astrophysics Data System (ADS)

    Idris, S.; Osadola, T.; Glesk, I.

    2013-02-01

    A novel incoherent OCDMA receiver with incorporated all-optical clock recovery for self-synchronization of a time gate for the multi access interferences (MAI) suppression and minimizing the effect of data time jitter in incoherent OCDMA system was successfully developed and demonstrated. The solution was implemented and tested in a multiuser environment in an out of the laboratory OCDMA testbed with two-dimensional wavelength-hopping time-spreading coding scheme and OC-48 (2.5 Gbp/s) data rate. The self-clocked all-optical time gate uses SOA-based fibre ring laser optical clock, recovered all-optically from the received OCDMA traffic to control its switching window for cleaning the autocorrelation peak from the surrounding MAI. A wider eye opening was achieved when the all-optically recovered clock from received data was used for synchronization if compared to a static approach with the RF clock being generated by a RF synthesizer. Clean eye diagram was also achieved when recovered clock is used to drive time gating.

  7. Wideband fixed-tuned SIS receiver for 200-GHz operation

    NASA Technical Reports Server (NTRS)

    Blundell, Raymond; Tong, Cheuk-Yu E.; Papa, D. Cosmo; Leombruno, R. Louie; Zhang, Xiaolei; Paine, Scott; Stern, Jeffrey A.; Leduc, Henry G.; Bumble, Bruce

    1995-01-01

    We report on the design and development of a heterodyne receiver, designed to cover the frequency range 176-256 GHz. This receiver incorporates a niobium superconductor-insulator-superconductor (SIS) tunnel junction mixer, which, chiefly for reasons of reliability and ease of operation, is a fixed-tuned waveguide design. On-chip tuning is provided to resonate out the junction's geometric capacitance and produce a good match to the waveguide circuit. Laboratory measurements on the first test receiver indicate that the required input bandwidth (about 40%) is achieved with an average receiver noise temperature of below 50 K. Mixer conversion gain is observed at some frequencies, and the lowest measured receiver noise is less than 30 K. Furthermore, the SIS mixer used in this receiver is of simple construction, is easy to assemble and is therefore a good candidate for duplication.

  8. Calibrated Noise Measurements with Induced Receiver Gain Fluctuations

    NASA Technical Reports Server (NTRS)

    Racette, Paul; Walker, David; Gu, Dazhen; Rajola, Marco; Spevacek, Ashly

    2011-01-01

    The lack of well-developed techniques for modeling changing statistical moments in our observations has stymied the application of stochastic process theory in science and engineering. These limitations were encountered when modeling the performance of radiometer calibration architectures and algorithms in the presence of non stationary receiver fluctuations. Analyses of measured signals have traditionally been limited to a single measurement series. Whereas in a radiometer that samples a set of noise references, the data collection can be treated as an ensemble set of measurements of the receiver state. Noise Assisted Data Analysis is a growing field of study with significant potential for aiding the understanding and modeling of non stationary processes. Typically, NADA entails adding noise to a signal to produce an ensemble set on which statistical analysis is performed. Alternatively as in radiometric measurements, mixing a signal with calibrated noise provides, through the calibration process, the means to detect deviations from the stationary assumption and thereby a measurement tool to characterize the signal's non stationary properties. Data sets comprised of calibrated noise measurements have been limited to those collected with naturally occurring fluctuations in the radiometer receiver. To examine the application of NADA using calibrated noise, a Receiver Gain Modulation Circuit (RGMC) was designed and built to modulate the gain of a radiometer receiver using an external signal. In 2010, an RGMC was installed and operated at the National Institute of Standards and Techniques (NIST) using their Noise Figure Radiometer (NFRad) and national standard noise references. The data collected is the first known set of calibrated noise measurements from a receiver with an externally modulated gain. As an initial step, sinusoidal and step-function signals were used to modulate the receiver gain, to evaluate the circuit characteristics and to study the performance of

  9. 47 CFR 15.121 - Scanning receivers and frequency converters used with scanning receivers.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... incapable of operating (tuning), or readily being altered by the user to operate, within the frequency bands...). Scanning receivers capable of “readily being altered by the user” include, but are not limited to, those... by this paragraph shall be placed in a prominent location in the instruction manual or pamphlet...

  10. Getting tough with home health accounts receivable.

    PubMed

    Cantone, L; Bullock, A

    2000-04-01

    Home health organizations seeking to improve the performance of their accounts receivable should concentrate first on establishing practices that promote the greatest percentage of clean claims and reviewing payments received to be sure rates paid are optimal. They also may find it worthwhile to survey their business office operations for potential improvements to key areas.

  11. Structural analysis of a reflux pool-boiler solar receiver

    NASA Astrophysics Data System (ADS)

    Hoffman, E. L.; Stone, C. M.

    1991-06-01

    Coupled thermal-structural finite element calculations of a reflux pool-boiler solar receiver were performed to characterize the operating stresses and to address issues affecting the service life of the receiver. Analyses performed using shell elements provided information for receiver material selection and design optimization. Calculations based on linear elastic fracture mechanics principles were performed using continuum elements to assess the vulnerability of a seam-weld to fatigue crack growth. All calculations were performed using ABAQUS, a general purpose finite element code, and elements specifically formulated for coupled thermal-structural analysis. Two materials were evaluated: 316L SS and Haynes 230 alloys. The receiver response was simulated for a combination of structural and thermal loads that represent the startup and operating conditions of the receiver. For both materials, maximum stresses in the receiver developed shortly after startup due to uneven temperature distribution across the receiver surface. The largest effective stress was near yield in the 316L SS receiver and below 39 percent of yield in the Haynes 230 receiver. The calculations demonstrated that stress reductions of over 25 percent could be obtained by reducing the aft dome thickness to one closer to the absorber. The fatigue calculations demonstrated that the stress distribution near the seam-weld notch depends primarily on the structural load created by internal pressurization of the receiver rather than the thermal, indicating that the thermal loads can be neglected when assessing the stress intensity near the seam-weld notch. The stress intensity factor, computed using the J-integral method and crack opening-displacement field equations, was significantly below the fatigue threshold for most steels. The calculations indicated that the weld notch was always loaded in compression, a condition which is not conducive to fatigue crack growth.

  12. Graphene integrated circuits: new prospects towards receiver realisation.

    PubMed

    Saeed, Mohamed; Hamed, Ahmed; Wang, Zhenxing; Shaygan, Mehrdad; Neumaier, Daniel; Negra, Renato

    2017-12-21

    This work demonstrates a design approach which enables the fabrication of fully integrated radio frequency (RF) and millimetre-wave frequency direct-conversion graphene receivers by adapting the frontend architecture to exploit the state-of-the-art performance of the recently reported wafer-scale CVD metal-insulator-graphene (MIG) diodes. As a proof-of-concept, we built a fully integrated microwave receiver in the frequency range 2.1-2.7 GHz employing the strong nonlinearity and the high responsivity of MIG diodes to successfully receive and demodulate complex, digitally modulated communication signals at 2.45 GHz. In addition, the fabricated receiver uses zero-biased MIG diodes and consumes zero dc power. With the flexibility to be fabricated on different substrates, the prototype receiver frontend is fabricated on a low-cost, glass substrate utilising a custom-developed MMIC process backend which enables the high performance of passive components. The measured performance of the prototype makes it suitable for Internet-of-Things (IoT) and Radio Frequency Identification (RFID) systems for medical and communication applications.

  13. Dynamic-Receive Focusing with High-Frequency Annular Arrays

    NASA Astrophysics Data System (ADS)

    Ketterling, J. A.; Mamou, J.; Silverman, R. H.

    High-frequency ultrasound is commonly employed for ophthalmic and small-animal imaging because of the fine-resolution images it affords. Annular arrays allow improved depth of field and lateral resolution versus commonly used single-element, focused transducers. The best image quality from an annular array is achieved by using synthetic transmit-to-receive focusing while utilizing data from all transmit-to-receive element combinations. However, annular arrays must be laterally scanned to form an image and this requires one pass for each of the array elements when implementing full synthetic transmit-to-receive focusing. A dynamic-receive focusing approach permits a single pass, although at a sacrifice of depth of field and lateral resolution. A five-element, 20-MHz annular array is examined to determine the acoustic beam properties for synthetic and dynamic-receive focusing. A spatial impulse response model is used to simulate the acoustic beam properties for each focusing case and then data acquired from a human eye-bank eye are processed to demonstrate the effect of each approach on image quality.

  14. Smooth time-dependent receiver operating characteristic curve estimators.

    PubMed

    Martínez-Camblor, Pablo; Pardo-Fernández, Juan Carlos

    2018-03-01

    The receiver operating characteristic curve is a popular graphical method often used to study the diagnostic capacity of continuous (bio)markers. When the considered outcome is a time-dependent variable, two main extensions have been proposed: the cumulative/dynamic receiver operating characteristic curve and the incident/dynamic receiver operating characteristic curve. In both cases, the main problem for developing appropriate estimators is the estimation of the joint distribution of the variables time-to-event and marker. As usual, different approximations lead to different estimators. In this article, the authors explore the use of a bivariate kernel density estimator which accounts for censored observations in the sample and produces smooth estimators of the time-dependent receiver operating characteristic curves. The performance of the resulting cumulative/dynamic and incident/dynamic receiver operating characteristic curves is studied by means of Monte Carlo simulations. Additionally, the influence of the choice of the required smoothing parameters is explored. Finally, two real-applications are considered. An R package is also provided as a complement to this article.

  15. Support System for Solar Receivers

    NASA Technical Reports Server (NTRS)

    Kiceniuk, T.

    1985-01-01

    Hinged split-ring mounts insure safe support of heavy receivers. In addition to safer operation and damage-free mounting system provides more accurate focusing, and small incremental adjustments of ring more easily made.

  16. Optical coupling elements for coherent optical multiport receivers

    NASA Astrophysics Data System (ADS)

    Langenhorst, Ralf

    1992-05-01

    Three by three (3 by 3) and four by four (4 by 4) port coupling elements and receivers for heterodyne multiport systems are realized. Commercial (3 by 3) fiber coupling elements were used to achieve a usual (3 by 3) port receiver and a (3 by 3) port receiver in pushpull switching, whose concept was theoretically and experimentally analyzed. It is established that intensity oscillations of laser sources are suppressed by pushpull switching. The influence of thermal noise of opto-electronic input levels is shown to be weaker than in usual (3 by 3) port and (4 by 4) port receivers. Thermal noise effect in pushpull switching is similar to this one in heterodyne receivers. An integrated optical coupling element in LiNbO3 was made with bridge circuit from four waveguide coupling elements and two phase converters, which are electro-optically tunable so that a continuous regulation of intermediate frequency phase can be compensated by temperature variations of the element. To obtain fiber-to-fiber losses lower than a dB, a compact crystal optical coupling element was developed with reference to polarization properties of optical waves. This element supplied the eight necessary intermediate frequency output signals. A direct experimental comparison of bandwidth efficiency of multiport and heterodyne receivers shows a factor two in optical area and a factor three in electrical frequency area.

  17. 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

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. Multistatic GNSS Receiver Array for Passive Air Surveillance

    NASA Astrophysics Data System (ADS)

    Wachtl, Stefan; Koch, Volker; Westphal, Robert; Schmidt, Lorenz-Peter

    2016-03-01

    The performance of a passive air surveillance sensor based on Global Navigation Satellite Systems (GNSS) is mainly limited by the receiver noise efficiency, the achievable signal processing gain and the radar cross section (RCS) of an airplane. For surveillance applications large detection ranges as well as a high probability of detection are crucial parameters. Due to the very low GNSS signal powers received on the earth's surface, high radar cross sections are mandatory to achieve detection ranges for airplanes at some kilometers distance. This paper will discuss a multistatic transmitter and receiver arrangement, which is indispensable to get a reasonable detection rate with respect to a hemispheric field of view. The strong performance dependency of such a sensor on the number of transmitters and receivers will be shown by means of some exemplary simulation results.

  3. 47 CFR 15.111 - Antenna power conduction limits for receivers.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 1 2014-10-01 2014-10-01 false Antenna power conduction limits for receivers... DEVICES Unintentional Radiators § 15.111 Antenna power conduction limits for receivers. (a) In addition to... CB receivers that provide terminals for the connection of an external receiving antenna may be tested...

  4. 47 CFR 15.111 - Antenna power conduction limits for receivers.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 1 2010-10-01 2010-10-01 false Antenna power conduction limits for receivers... DEVICES Unintentional Radiators § 15.111 Antenna power conduction limits for receivers. (a) In addition to... CB receivers that provide terminals for the connection of an external receiving antenna may be tested...

  5. 47 CFR 15.111 - Antenna power conduction limits for receivers.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 1 2013-10-01 2013-10-01 false Antenna power conduction limits for receivers... DEVICES Unintentional Radiators § 15.111 Antenna power conduction limits for receivers. (a) In addition to... CB receivers that provide terminals for the connection of an external receiving antenna may be tested...

  6. 47 CFR 15.111 - Antenna power conduction limits for receivers.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 1 2012-10-01 2012-10-01 false Antenna power conduction limits for receivers... DEVICES Unintentional Radiators § 15.111 Antenna power conduction limits for receivers. (a) In addition to... CB receivers that provide terminals for the connection of an external receiving antenna may be tested...

  7. 47 CFR 15.111 - Antenna power conduction limits for receivers.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 1 2011-10-01 2011-10-01 false Antenna power conduction limits for receivers... DEVICES Unintentional Radiators § 15.111 Antenna power conduction limits for receivers. (a) In addition to... CB receivers that provide terminals for the connection of an external receiving antenna may be tested...

  8. 33 CFR 17.01-10 - Authority to receive gifts.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Authority to receive gifts. 17.01... GENERAL UNITED STATES COAST GUARD GENERAL GIFT FUND General Provisions § 17.01-10 Authority to receive gifts. (a) The Commandant, United States Coast Guard, may accept, receive, hold, or administer gifts...

  9. 5 CFR 551.425 - Time spent receiving medical attention.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Time spent receiving medical attention... Relation to Other Activities § 551.425 Time spent receiving medical attention. (a) Time spent waiting for and receiving medical attention for illness or injury shall be considered hours of work if: (1) The...

  10. Radio Astronomy Software Defined Receiver Project

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Vacaliuc, Bogdan; Leech, Marcus; Oxley, Paul

    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 usermore » 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.« less

  11. 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.

  12. TDRSS S-shuttle unique receiver equipment

    NASA Astrophysics Data System (ADS)

    Weinberg, A.; Schwartz, J. J.; Spearing, R.

    1985-01-01

    Beginning with STS-9, the Tracking and Date Relay Satellite system (TDRSS) will start providing S- and Ku-band communications and tracking support to the Space Shuttle and its payloads. The most significant element of this support takes place at the TDRSS White Sands Ground Terminal, which processes the Shuttle return link S- and Ku-band signals. While Ku-band hardware available to other TDRSS users is also applied to Ku-Shuttle, stringent S-Shuttle link margins have precluded the application of the standard TDRSS S-band processing equipment to S-Shuttle. It was therfore found necessary to develop a unique S-Shuttle Receiver that embodies state-of-the-art digital technology and processing techniques. This receiver, developed by Motorola, Inc., enhances link margins by 1.5 dB relative to the standard S-band equipment and its bit error rate performance is within a few tenths of a dB of theory. An overview description of the Space Shuttle Receiver Equipment (SSRE) is presented which includes the presentation of block diagrams and salient design features. Selected, measured performance results are also presented.

  13. A wide-band 760-GHz planar integrated Schottky receiver

    NASA Technical Reports Server (NTRS)

    Gearhart, Steven S.; Hesler, Jeffrey; Bishop, William L.; Crowe, Thomas W.; Rebeiz, Gabriel M.

    1993-01-01

    A wideband planar integrated heterodyne receiver has been developed for use at submillimeter-wave to FIR frequencies. The receiver consists of a log-periodic antenna integrated with a planar 0.8-micron GaAs Schottky diode. The monolithic receiver is placed on a silicon lens and has a measured room temperature double side-band conversion loss and noise temperature of 14.9 +/- 1.0 dB and 8900 +/- 500 K, respectively, at 761 GHz. These results represent the best performance to date for room temperature integrated receivers at this frequency.

  14. Frequency Estimator Performance for a Software-Based Beacon Receiver

    NASA Technical Reports Server (NTRS)

    Zemba, Michael J.; Morse, Jacquelynne Rose; Nessel, James A.; Miranda, Felix

    2014-01-01

    As propagation terminals have evolved, their design has trended more toward a software-based approach that facilitates convenient adjustment and customization of the receiver algorithms. One potential improvement is the implementation of a frequency estimation algorithm, through which the primary frequency component of the received signal can be estimated with a much greater resolution than with a simple peak search of the FFT spectrum. To select an estimator for usage in a QV-band beacon receiver, analysis of six frequency estimators was conducted to characterize their effectiveness as they relate to beacon receiver design.

  15. Low-noise 115-GHz receiver using superconducting tunnel junctions

    NASA Technical Reports Server (NTRS)

    Pan, S.-K.; Feldman, M. J.; Kerr, A. R.; Timble, P.

    1983-01-01

    A 110-118-GHz receiver based on a superconducting quasiparticle tunnel junction mixer is described. The single-sideband noise temperature is as low as 68 + or - 3 K. This is nearly twice the sensitivity of any other receiver at this frequency. The receiver was designed using a low-frequency scale model in conjunction with the quantum mixer theory. A scaled version of the receiver for operation at 46 GHz has a single-sideband noise temperature of 55 K. The factors leading to the success of this design are discussed.

  16. Frequency Estimator Performance for a Software-Based Beacon Receiver

    NASA Technical Reports Server (NTRS)

    Zemba, Michael J.; Morse, Jacquelynne R.; Nessel, James A.

    2014-01-01

    As propagation terminals have evolved, their design has trended more toward a software-based approach that facilitates convenient adjustment and customization of the receiver algorithms. One potential improvement is the implementation of a frequency estimation algorithm, through which the primary frequency component of the received signal can be estimated with a much greater resolution than with a simple peak search of the FFT spectrum. To select an estimator for usage in a Q/V-band beacon receiver, analysis of six frequency estimators was conducted to characterize their effectiveness as they relate to beacon receiver design.

  17. 32 CFR 750.7 - Claims: Action by receiving command.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 32 National Defense 5 2011-07-01 2011-07-01 false Claims: Action by receiving command. 750.7... CLAIMS REGULATIONS General Provisions for Claims § 750.7 Claims: Action by receiving command. (a) Record date of receipt. The first command receiving a claim shall stamp or mark the date of receipt on the...

  18. 32 CFR 750.7 - Claims: Action by receiving command.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 32 National Defense 5 2013-07-01 2013-07-01 false Claims: Action by receiving command. 750.7... CLAIMS REGULATIONS General Provisions for Claims § 750.7 Claims: Action by receiving command. (a) Record date of receipt. The first command receiving a claim shall stamp or mark the date of receipt on the...

  19. 32 CFR 750.7 - Claims: Action by receiving command.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 5 2010-07-01 2010-07-01 false Claims: Action by receiving command. 750.7... CLAIMS REGULATIONS General Provisions for Claims § 750.7 Claims: Action by receiving command. (a) Record date of receipt. The first command receiving a claim shall stamp or mark the date of receipt on the...

  20. 32 CFR 750.7 - Claims: Action by receiving command.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 32 National Defense 5 2014-07-01 2014-07-01 false Claims: Action by receiving command. 750.7... CLAIMS REGULATIONS General Provisions for Claims § 750.7 Claims: Action by receiving command. (a) Record date of receipt. The first command receiving a claim shall stamp or mark the date of receipt on the...

  1. 32 CFR 750.7 - Claims: Action by receiving command.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 32 National Defense 5 2012-07-01 2012-07-01 false Claims: Action by receiving command. 750.7... CLAIMS REGULATIONS General Provisions for Claims § 750.7 Claims: Action by receiving command. (a) Record date of receipt. The first command receiving a claim shall stamp or mark the date of receipt on the...

  2. Performance Assessment of Two GPS Receivers on Space Shuttle

    NASA Technical Reports Server (NTRS)

    Schroeder, Christine A.; Schutz, Bob E.

    1996-01-01

    Space Shuttle STS-69 was launched on September 7, 1995, carrying the Wake Shield Facility (WSF-02) among its payloads. The mission included two GPS receivers: a Collins 3M receiver onboard the Endeavour and an Osborne flight TurboRogue, known as the TurboStar, onboard the WSF-02. Two of the WSF-02 GPS Experiment objectives were to: (1) assess the ability to use GPS in a relative satellite positioning mode using the receivers on Endeavour and WSF-02; and (2) assess the performance of the receivers to support high precision orbit determination at the 400 km altitude. Three ground tests of the receivers were conducted in order to characterize the respective receivers. The analysis of the tests utilized the Double Differencing technique. A similar test in orbit was conducted during STS-69 while the WSF-02 was held by the Endeavour robot arm for a one hour period. In these tests, biases were observed in the double difference pseudorange measurements, implying that biases up to 140 m exist which do not cancel in double differencing. These biases appear to exist in the Collins receiver, but their effect can be mitigated by including measurement bias parameters to accommodate them in an estimation process. An additional test was conducted in which the orbit of the combined Endeavour/WSF-02 was determined independently with each receiver. These one hour arcs were based on forming double differences with 13 TurboRogue receivers in the global IGS network and estimating pseudorange biases for the Collins. Various analyses suggest the TurboStar overall orbit accuracy is about one to two meters for this period, based on double differenced phase residuals of 34 cm. These residuals indicate the level of unmodeled forces on Endeavour produced by gravitational and nongravitational effects. The rms differences between the two independently determined orbits are better than 10 meters, thereby demonstrating the accuracy of the Collins-determined orbit at this level as well as the

  3. 12 CFR 627.2725 - Powers and duties of the receiver.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... receivership and all costs of carrying out or exercising the rights, powers, privileges, and duties as receiver... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Powers and duties of the receiver. 627.2725..., RECEIVERS, AND VOLUNTARY LIQUIDATIONS Receivers and Receiverships § 627.2725 Powers and duties of the...

  4. 12 CFR 627.2725 - Powers and duties of the receiver.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... receivership and all costs of carrying out or exercising the rights, powers, privileges, and duties as receiver... 12 Banks and Banking 6 2011-01-01 2011-01-01 false Powers and duties of the receiver. 627.2725..., RECEIVERS, AND VOLUNTARY LIQUIDATIONS Receivers and Receiverships § 627.2725 Powers and duties of the...

  5. Physical and non-physical energy in scattered wave source-receiver interferometry.

    PubMed

    Meles, Giovanni Angelo; Curtis, Andrew

    2013-06-01

    Source-receiver interferometry allows Green's functions between sources and receivers to be estimated by means of convolution and cross-correlation of other wavefields. Source-receiver interferometry has been observed to work surprisingly well in practical applications when theoretical requirements (e.g., complete enclosing boundaries of other sources and receivers) are contravened: this paper contributes to explain why this may be true. Commonly used inter-receiver interferometry requires wavefields to be generated around specific stationary points in space which are controlled purely by medium heterogeneity and receiver locations. By contrast, application of source-receiver interferometry constructs at least kinematic information about physically scattered waves between a source and a receiver by cross-convolution of scattered waves propagating from and to any points on the boundary. This reduces the ambiguity in interpreting wavefields generated using source-receiver interferometry with only partial boundaries (as is standard in practical applications), as it allows spurious or non-physical energy in the constructed Green's function to be identified and ignored. Further, source-receiver interferometry (which includes a step of inter-receiver interferometry) turns all types of non-physical or spurious energy deriving from inter-receiver interferometry into what appears to be physical energy. This explains in part why source-receiver interferometry may perform relatively well compared to inter-receiver interferometry when constructing scattered wavefields.

  6. Performance and durability testing of parabolic trough receivers

    NASA Astrophysics Data System (ADS)

    Lei, Dongqiang; Fu, Xuqiang; Zhao, Dongming; Yuan, Guofeng; Wang, Zhifeng; Guo, Minghuan

    2017-06-01

    The paper describes the key performance and durability testing facilities of the parabolic trough receiver developed by Institute of Electrical Engineering, Chinese Academy of Sciences. The indoor heat loss test can be applied at 4-7 different temperature levels within 200-550 on receivers. The optical efficiency test bench consists of 12 metal halide lamps as the solar simulator and a 5 m length half-elliptical cylinder reflector with flat end reflectors. 3 ultra-precision temperature sensors are used in receiver each end to get the temperature difference. The residual gas analysis test bench is applied to analyze and predict the vacuum lifetime of the receiver. It can test the variations of composition and partial pressure of residual gases with temperature and time in the receiver annulus space by a high sensitivity quadrupole mass spectrometer gas analyzer. A coating accelerated ageing test bench, which is also used to test the thermal cycle, has been developed. This test bench uses the absorber tube of the recevier as the resistance heater to heat up the whole receiver. The coating lifetime can be predicted by the Arrhenius parameters. For the cycling test, the compressed air is used to directly cool the inner surface of the absorber tube. The thermal cycling test is performed with temperature cycles from 150 °C to 450 °C for 160 cycles. The maximum thermal cycling frequency is 8 cycles per day. The mechanical fatigue test bench is used to test the bellows and the glass-to-metal seals durability at the same time. Both bellows are expanded and compressed to 6.5 mm in turn with 10,000 cycles. A new rotating test bench was also developed to test the thermal efficiency of the receiver.

  7. A reprogrammable receiver architecture for wireless signal interception

    NASA Astrophysics Data System (ADS)

    Yao, Timothy S.

    2003-09-01

    In this paper, a re-programmable receiver architecture, based on software-defined-radio concept, for wireless signal interception is presented. The radio-frequency (RF) signal that the receiver would like to intercept may come from a terrestrial cellular network or communication satellites, which their carrier frequency are in the range from 800 MHz (civilian mobile) to 15 GHz (Ku band). To intercept signals from such a wide range of frequency in these variant communication systems, the traditional way is to deploy multiple receivers to scan and detect the desired signal. This traditional approach is obviously unattractive due to the cost, efficiency, and accuracy. Instead, we propose a universal receiver, which is software-driven and re-configurable, to intercept signals of interest. The software-defined-radio based receiver first intercepts RF energy of wide spectrum (25MHz) through antenna, performs zero-IF down conversion (homodyne architecture) to baseband, and digital channelizes the baseband signal. The channelization module is a bank of high performance digital filters. The bandwidth of the filter bank is programmable according to the wireless communication protocol under watch. In the baseband processing, high-performance digital signal processors carry out the detection process and microprocessors handle the communication protocols. The baseband processing is also re-configurable for different wireless standards and protocol. The advantages of the software-defined-radio architecture over traditional RF receiver make it a favorable technology for the communication signal interception and surveillance.

  8. Fast-synchronizing high-fidelity spread-spectrum receiver

    DOEpatents

    Moore, Michael Roy; Smith, Stephen Fulton; Emery, Michael Steven

    2004-06-01

    A fast-synchronizing receiver having a circuit including an equalizer configured for manipulating an analog signal; a detector in communication with the equalizer; a filter in communication with the detector; an oscillator in communication with the filter; a gate for receiving the manipulated signal; a circuit portion for synchronizing and tracking the manipulated signal; a summing circuit in communication with the circuit portion; and an output gate.

  9. The Stability of GPS Carrier-Phase Receivers

    DTIC Science & Technology

    2010-11-01

    Frequency Transfer ( TWSTFT ) method [2]. For both CP and TWSTFT , accuracy in time transfer is achieved through special calibration efforts that retain...View (CV) receivers and TWSTFT equipment. Many of these geodetic receivers operate continuously within the International GNSS Service (IGS), and...with TWSTFT , GPS CV, and GPS P3. If ionosphere-free measurements are used in combination with nominally compensated tropospheric corrections, a

  10. An Array of Optical Receivers for Deep-Space Communications

    NASA Technical Reports Server (NTRS)

    Vilnrotter, Chi-Wung; Srinivasan, Meera; Andrews, Kenneth

    2007-01-01

    An array of small optical receivers is proposed as an alternative to a single large optical receiver for high-data-rate communications in NASA s Deep Space Network (DSN). Because the telescope for a single receiver capable of satisfying DSN requirements must be greater than 10 m in diameter, the design, building, and testing of the telescope would be very difficult and expensive. The proposed array would utilize commercially available telescopes of 1-m or smaller diameter and, therefore, could be developed and verified with considerably less difficulty and expense. The essential difference between a single-aperture optical-communications receiver and an optical-array receiver is that a single-aperture receiver focuses all of the light energy it collects onto the surface of an optical detector, whereas an array receiver focuses portions of the total collected energy onto separate detectors, optically detects each fractional energy component, then combines the electrical signal from the array of detector outputs to form the observable, or "decision statistic," used to decode the transmitted data. A conceptual block diagram identifying the key components of the optical-array receiver suitable for deep-space telemetry reception is shown in the figure. The most conspicuous feature of the receiver is the large number of small- to medium-size telescopes, with individual apertures and number of telescopes selected to make up the desired total collecting area. This array of telescopes is envisioned to be fully computer- controlled via the user interface and prediction-driven to achieve rough pointing and tracking of the desired spacecraft. Fine-pointing and tracking functions then take over to keep each telescope pointed toward the source, despite imperfect pointing predictions, telescope-drive errors, and vibration caused by wind.

  11. Semuloparin for thromboprophylaxis in patients receiving chemotherapy for cancer.

    PubMed

    Agnelli, Giancarlo; George, Daniel J; Kakkar, Ajay K; Fisher, William; Lassen, Michael R; Mismetti, Patrick; Mouret, Patrick; Chaudhari, Umesh; Lawson, Francesca; Turpie, Alexander G G

    2012-02-16

    Patients receiving chemotherapy for cancer are at increased risk for venous thromboembolism. Limited data support the clinical benefit of antithrombotic prophylaxis. In this double-blind, multicenter trial, we evaluated the efficacy and safety of the ultra-low-molecular-weight heparin semuloparin for prevention of venous thromboembolism in patients receiving chemotherapy for cancer. Patients with metastatic or locally advanced solid tumors who were beginning to receive a course of chemotherapy were randomly assigned to receive subcutaneous semuloparin, 20 mg once daily, or placebo until there was a change of chemotherapy regimen. The primary efficacy outcome was the composite of any symptomatic deep-vein thrombosis, any nonfatal pulmonary embolism, and death related to venous thromboembolism. Clinically relevant bleeding (major and nonmajor) was the main safety outcome. The median treatment duration was 3.5 months. Venous thromboembolism occurred in 20 of 1608 patients (1.2%) receiving semuloparin, as compared with 55 of 1604 (3.4%) receiving placebo (hazard ratio, 0.36; 95% confidence interval [CI], 0.21 to 0.60; P<0.001), with consistent efficacy among subgroups defined according to the origin and stage of cancer and the baseline risk of venous thromboembolism. The incidence of clinically relevant bleeding was 2.8% and 2.0% in the semuloparin and placebo groups, respectively (hazard ratio, 1.40; 95% CI, 0.89 to 2.21). Major bleeding occurred in 19 of 1589 patients (1.2%) receiving semuloparin and 18 of 1583 (1.1%) receiving placebo (hazard ratio, 1.05; 95% CI, 0.55 to 1.99). Incidences of all other adverse events were similar in the two study groups. Semuloparin reduces the incidence of thromboembolic events in patients receiving chemotherapy for cancer, with no apparent increase in major bleeding. (Funded by Sanofi; ClinicalTrials.gov number, NCT00694382.).

  12. A superconducting tunnel junction receiver for millimeter-wave astronomy

    NASA Technical Reports Server (NTRS)

    Pan, S. K.; Kerr, A. R.

    1986-01-01

    The development and construction of an ultralow noise heterodyne receiver for millimeter wave astronomy is described along with its use for 115.3 GHz Co line observations. The receiver uses a Superconductor-Insulator-Superconductor (SIS) quasiparticle tunnel junction mixer to convert the millimeter wave signal to a microwave intermediate frequency. Experiments aimed at quantitative verification of J. R. Tucker's quantum mixer theory are studied, to see whether it could be used as the basis for the design of a practical receiver. The experimental results were in excellent agreement with the theory, assuming the three frequency approximation. Infinite available gain and negative output resistance were observed for the first time, nonclassical effects which are not seen in conventional diode mixers. Using Tucker's theory, an SIS receiver was then designed and constructed. At 115 GHz, the single sideband receiver noise temperature is 83K, the lowest ever reported in this frequency range. A CO survey toward Cygnus-X region, using this SIS receiver on the Columbia-GISS 4 ft. telescope, is also described.

  13. Solar central receiver reformer system for ammonia plants

    NASA Astrophysics Data System (ADS)

    1980-07-01

    An overview of a study to retrofit the Valley Nitrogen Producers, Inc., El Centro, California 600 ST/SD Ammonia Plant with Solar Central Receiver Technology is presented. The retrofit system consists of a solar central receiver reformer (SCRR) operating in parallel with the existing fossil fired reformer. Steam and hydrocarbon react in the catalyst filled tubes of the inner cavity receiver to form a hydrogen rich mixture which is the syngas feed for the ammonia production. The SCRR system will displace natural gas presently used in the fossil reformer combustion chamber.

  14. 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.

  15. Sensible heat receiver for solar dynamic space power system

    NASA Astrophysics Data System (ADS)

    Perez-Davis, Marla E.; Gaier, James R.; Petrefski, Chris

    A sensible heat receiver is considered which uses a vapor grown carbon fiber-carbon (VGCF/C) composite as the thermal storage medium and which was designed for a 7-kW Brayton engine. This heat receiver stores the required energy to power the system during eclipse in the VGCF/C composite. The heat receiver thermal analysis was conducted through the Systems Improved Numerical Differencing Analyzer and Fluid Integrator (SINDA) software package. The sensible heat receiver compares well with other latent and advanced sensible heat receivers analyzed in other studies, while avoiding the problems associated with latent heat storage salts and liquid metal heat pipes. The concept also satisfies the design requirements for a 7-kW Brayton engine system. The weight and size of the system can be optimized by changes in geometry and technology advances for this new material.

  16. Hybrid sodium heat pipe receivers for dish/Stirling systems

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Laing, D.; Reusch, M.

    1997-12-31

    The design of a hybrid solar/gas heat pipe receiver for the SBP 9 kW dish/Stirling system using a United Stirling AB V160 Stirling engine and the results of on-sun testing in alternative and parallel mode will be reported. The receiver is designed to transfer a thermal power of 35 kW. The heat pipe operates at around 800 C, working fluid is sodium. Operational options are solar-only, gas augmented and gas-only mode. Also the design of a second generation hybrid heat pipe receiver currently developed under a EU-funded project, based on the experience gained with the first hybrid receiver, will bemore » reported. This receiver is designed for the improved SPB/L. and C.-10 kW dish/Stirling system with the reworked SOLO V161 Stirling engine.« less

  17. Sensible heat receiver for solar dynamic space power system

    NASA Technical Reports Server (NTRS)

    Perez-Davis, Marla E.; Gaier, James R.; Petrefski, Chris

    1991-01-01

    A sensible heat receiver considered in this study uses a vapor grown carbon fiber-carbon (VGCF/C) composite as the thermal storage media and was designed for a 7 kW Brayton engine. The proposed heat receiver stores the required energy to power the system during eclipse in the VGCF/C composite. The heat receiver thermal analysis was conducted through the Systems Improved Numerical Differencing Analyzer and Fluid Integrator (SINDA) software package. The sensible heat receiver compares well with other latent and advanced sensible heat receivers analyzed in other studies while avoiding the problems associated with latent heat storage salts and liquid metal heat pipes. The concept also satisfies the design requirements for a 7 kW Brayton engine system. The weight and size of the system can be optimized by changes in geometry and technology advances for this new material.

  18. Sensible heat receiver for solar dynamic space power system

    NASA Technical Reports Server (NTRS)

    Perez-Davis, Marla E.; Gaier, James R.; Petrefski, Chris

    1991-01-01

    A sensible heat receiver is considered which uses a vapor grown carbon fiber-carbon (VGCF/C) composite as the thermal storage medium and which was designed for a 7-kW Brayton engine. This heat receiver stores the required energy to power the system during eclipse in the VGCF/C composite. The heat receiver thermal analysis was conducted through the Systems Improved Numerical Differencing Analyzer and Fluid Integrator (SINDA) software package. The sensible heat receiver compares well with other latent and advanced sensible heat receivers analyzed in other studies, while avoiding the problems associated with latent heat storage salts and liquid metal heat pipes. The concept also satisfies the design requirements for a 7-kW Brayton engine system. The weight and size of the system can be optimized by changes in geometry and technology advances for this new material.

  19. Radiation energy receiver for laser and solar propulsion systems

    NASA Technical Reports Server (NTRS)

    Rault, D. F. G.; Hertzberg, A.

    1983-01-01

    The concept of remotely heating a rocket propellant with a high intensity radiant energy flux is especially attractive due to its high specific impulse and large payload mass capabilities. In this paper, a radiation receiver-thruster which is especially suited to the particular thermodynamic and spectral characteristics of highly concentrated solar energy is proposed. In this receiver, radiant energy is volumetrically absorbed within a hydrogen gas seeded with alkali metal vapors. The alkali atoms and molecules absorb the radiant flux and, subsequently, transfer their internal excitation to hydrogen molecules through collisional quenching. It is shown that such a radiation receiver would outperform a blackbody cavity type receiver in both efficiency and maximum operating temperatures. A solar rocket equipped with such a receiver-thruster would deliver thrusts of several hundred newtons at a specific impulse of 1000 seconds.

  20. 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.

  1. Design of radar receivers

    NASA Astrophysics Data System (ADS)

    Sokolov, M. A.

    This handbook treats the design and analysis of of pulsed radar receivers, with emphasis on elements (especially IC elements) that implement optimal and suboptimal algorithms. The design methodology is developed from the viewpoint of statistical communications theory. Particular consideration is given to the synthesis of single-channel and multichannel detectors, the design of analog and digital signal-processing devices, and the analysis of IF amplifiers.

  2. United States Department of Energy solar receiver technology development

    NASA Astrophysics Data System (ADS)

    Klimas, P. C.; Diver, R. B.; Chavez, J. M.

    The United States Department of Energy (DOE), through Sandia National Laboratories, has been conducting a Solar Thermal Receiver Technology Development Program, which maintains a balance between analytical modeling, bench and small scale testing, and experimentation conducted at scales representative of commercially-sized equipment. Central receiver activities emphasize molten salt-based systems on large scales and volumetric devices in the modeling and small scale testing. These receivers are expected to be utilized in solar power plants rated between 100 and 200 MW. Distributed receiver research focuses on liquid metal refluxing devices. These are intended to mate parabolic dish concentrators with Stirling cycle engines in the 5 to 25 kW(sub e) power range. The effort in the area of volumetric receivers is less intensive and highly cooperative in nature. A ceramic foam absorber of Sandia design was successfully tested on the 200 kW(sub t) test bed at Plataforma Solar during 1989. Material integrity during the approximately 90-test series was excellent. Significant progress has been made with parabolic dish concentrator-mounted receivers using liquid metals (sodium or a potassium/sodium mixture) as heat transport media. Sandia has successfully solar-tested a pool boiling reflux receiver sized to power a 25 kW Stirling engine. Boiling stability and transient operation were both excellent. This document describes these activities in detail and will outline plans for future development.

  3. LANL receiver system development

    DOE Office of Scientific and Technical Information (OSTI.GOV)

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

    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 bemore » 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.« less

  4. 7 CFR 1956.71 - Settling uncollectible recapture receivables.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 14 2010-01-01 2009-01-01 true Settling uncollectible recapture receivables. 1956.71 Section 1956.71 Agriculture Regulations of the Department of Agriculture (Continued) RURAL HOUSING SERVICE... Multi-Family Housing § 1956.71 Settling uncollectible recapture receivables. The settlement of...

  5. A Polarization-Diversity Simultaneous-Lobing Angle-Tracking Receiver

    NASA Technical Reports Server (NTRS)

    Renhult, W. B.

    1961-01-01

    This report describes a simultaneous-lobing angle-tracking receiver operating in the 225-260 milli-cycle-per-second telemetry band and employing polarization diversity. Its operation is considered primarily in the context of the Mercury range and tracking of the Mercury capsule. Several methods of providing diversity are briefly considered, and a number of ways of implementing the phase shifts required at one polarization for coherent signal addition are discussed. A prototype receiver is briefly described although circuitry which may be somewhat novel is covered in greater detail. No attempt has been made to include all of the sophistication one might expect in a receiver of this type; circuits have been simplified in some areas where, for example, a manual control can replace an automatic function and reduce complexity. Some conclusions are drawn as to how this receiver might perform in the Mercury environment.

  6. Contrasting two models of academic self-efficacy--domain-specific versus cross-domain--in children receiving and not receiving special instruction in mathematics.

    PubMed

    Jungert, Tomas; Hesser, Hugo; Träff, Ulf

    2014-10-01

    In social cognitive theory, self-efficacy is domain-specific. An alternative model, the cross-domain influence model, would predict that self-efficacy beliefs in one domain might influence performance in other domains. Research has also found that children who receive special instruction are not good at estimating their performance. The aim was to test two models of how self-efficacy beliefs influence achievement, and to contrast children receiving special instruction in mathematics with normally-achieving children. The participants were 73 fifth-grade children who receive special instruction and 70 children who do not receive any special instruction. In year four and five, the children's skills in mathematics and reading were assessed by national curriculum tests, and in their fifth year, self-efficacy in mathematics and reading were measured. Structural equation modeling showed that in domains where children do not receive special instruction in mathematics, self-efficacy is a mediating variable between earlier and later achievement in the same domain. Achievement in mathematics was not mediated by self-efficacy in mathematics for children who receive special instruction. For normal achieving children, earlier achievement in the language domain had an influence on later self-efficacy in the mathematics domain, and self-efficacy beliefs in different domains were correlated. Self-efficacy is mostly domain specific, but may play a different role in academic performance depending on whether children receive special instruction. The results of the present study provided some support of the Cross-Domain Influence Model for normal achieving children. © 2014 Scandinavian Psychological Associations and John Wiley & Sons Ltd.

  7. Kramers-Kronig receiver operable without digital upsampling.

    PubMed

    Bo, Tianwai; Kim, Hoon

    2018-05-28

    The Kramers-Kronig (KK) receiver is capable of retrieving the phase information of optical single-sideband (SSB) signal from the optical intensity when the optical signal satisfies the minimum phase condition. Thus, it is possible to direct-detect the optical SSB signal without suffering from the signal-signal beat interference and linear transmission impairments. However, due to the spectral broadening induced by nonlinear operations in the conventional KK algorithm, it is necessary to employ the digital upsampling at the beginning of the digital signal processing (DSP). The increased number of samples at the DSP would hinder the real-time implementation of this attractive receiver. Hence, we propose a new DSP algorithm for KK receiver operable at 2 samples per symbol. We adopt a couple of mathematical approximations to avoid the use of nonlinear operations such as logarithm and exponential functions. By using the proposed algorithm, we demonstrate the transmission of 112-Gb/s SSB orthogonal frequency-division-multiplexed signal over an 80-km fiber link. The results show that the proposed algorithm operating at 2 samples per symbol exhibits similar performance to the conventional KK one operating at 6 samples per symbol. We also present the error analysis of the proposed algorithm for KK receiver in comparison with the conventional one.

  8. 12 CFR 614.4700 - Financing foreign trade receivables.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 12 Banks and Banking 7 2013-01-01 2013-01-01 false Financing foreign trade receivables. 614.4700... OPERATIONS Banks for Cooperatives and Agricultural Credit Banks Financing International Trade § 614.4700 Financing foreign trade receivables. (a) Banks for cooperatives and agricultural credit banks, under...

  9. 12 CFR 614.4700 - Financing foreign trade receivables.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 12 Banks and Banking 7 2014-01-01 2014-01-01 false Financing foreign trade receivables. 614.4700... OPERATIONS Banks for Cooperatives and Agricultural Credit Banks Financing International Trade § 614.4700 Financing foreign trade receivables. (a) Banks for cooperatives and agricultural credit banks, under...

  10. 12 CFR 614.4700 - Financing foreign trade receivables.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... OPERATIONS Banks for Cooperatives and Agricultural Credit Banks Financing International Trade § 614.4700 Financing foreign trade receivables. (a) Banks for cooperatives and agricultural credit banks, under... 12 Banks and Banking 7 2012-01-01 2012-01-01 false Financing foreign trade receivables. 614.4700...

  11. 12 CFR 614.4700 - Financing foreign trade receivables.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Financing foreign trade receivables. 614.4700... OPERATIONS Banks for Cooperatives and Agricultural Credit Banks Financing International Trade § 614.4700 Financing foreign trade receivables. (a) Banks for cooperatives and agricultural credit banks, under...

  12. 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.

  13. Optical superheterodyne receiver uses laser for local oscillator

    NASA Technical Reports Server (NTRS)

    Lucy, R. F.

    1966-01-01

    Optical superheterodyne receiver uses a laser coupled to a frequency translator to supply both the incident signal and local oscillator signal and thus permit reception of amplitude modulated video bandwidth signals through the atmosphere. This receiver is useful in scientific propagation experiments, tracking experiments, and communication experiments.

  14. Does receiving genetic counseling impact genetic counselor practice?

    PubMed

    Peters, Elizabeth; McCarthy Veach, Patricia; Ward, Erin E; LeRoy, Bonnie S

    2004-10-01

    This study was an investigation of whether genetic counselors have received genetic counseling and if so, how they believe it affects their practice. One thousand genetic counselors were mailed surveys about the nature of genetic counseling services received, impact on their clinical practice, frequency and reasons for disclosing about their receipt of counseling to their clients, and demographics. Ninety-three of the 510 respondents reported receiving genetic counseling. Of these, almost three-fourths were practicing genetic counselors while receiving services. Reasons for services include prenatal concerns, family history of cancer, and history/risk of other genetic conditions. Frequently endorsed effects on practice include increased empathy and understanding of client decisions, feeling more connected with clients, greater emphasis on psychosocial support, and sympathy. Forty-six respondents disclosed to clients about their receipt of genetic counseling. Prevalent reasons include client asked, help clients feel they are not alone, demonstrate counselor understanding, decrease client anxiety, build rapport, and normalize client feelings. Practice and research recommendations are given.

  15. 20 CFR 663.240 - Are there particular intensive services an individual must receive before receiving training...

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... service, such as development of an individual employment plan with a case manager or individual counseling and career planning, before the individual may receive training services. (b) The case file must...

  16. Calibration of Hurricane Imaging Radiometer C-Band Receivers

    NASA Technical Reports Server (NTRS)

    Biswas, Sayak K.; Cecil, Daniel J.; James, Mark W.

    2017-01-01

    The laboratory calibration of airborne Hurricane Imaging Radiometer's C-Band multi-frequency receivers is described here. The method used to obtain the values of receiver frontend loss, internal cold load brightness temperature and injected noise diode temperature is presented along with the expected RMS uncertainty in the final calibration.

  17. 5 CFR 582.201 - Agent to receive process.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Agent to receive process. 582.201 Section 582.201 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS COMMERCIAL GARNISHMENT OF FEDERAL EMPLOYEES' PAY Service of Legal Process § 582.201 Agent to receive process. (a) Except...

  18. 5 CFR 581.201 - Agent to receive process.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 5 Administrative Personnel 1 2014-01-01 2014-01-01 false Agent to receive process. 581.201 Section 581.201 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS PROCESSING GARNISHMENT ORDERS FOR CHILD SUPPORT AND/OR ALIMONY Service of Process § 581.201 Agent to receive process. (a...

  19. 5 CFR 582.201 - Agent to receive process.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 5 Administrative Personnel 1 2014-01-01 2014-01-01 false Agent to receive process. 582.201 Section 582.201 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS COMMERCIAL GARNISHMENT OF FEDERAL EMPLOYEES' PAY Service of Legal Process § 582.201 Agent to receive process. (a) Except...

  20. 5 CFR 581.201 - Agent to receive process.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 5 Administrative Personnel 1 2012-01-01 2012-01-01 false Agent to receive process. 581.201 Section 581.201 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS PROCESSING GARNISHMENT ORDERS FOR CHILD SUPPORT AND/OR ALIMONY Service of Process § 581.201 Agent to receive process. (a...

  1. 5 CFR 581.201 - Agent to receive process.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Agent to receive process. 581.201 Section 581.201 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS PROCESSING GARNISHMENT ORDERS FOR CHILD SUPPORT AND/OR ALIMONY Service of Process § 581.201 Agent to receive process. (a...

  2. 5 CFR 582.201 - Agent to receive process.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 5 Administrative Personnel 1 2012-01-01 2012-01-01 false Agent to receive process. 582.201 Section 582.201 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS COMMERCIAL GARNISHMENT OF FEDERAL EMPLOYEES' PAY Service of Legal Process § 582.201 Agent to receive process. (a) Except...

  3. 5 CFR 581.201 - Agent to receive process.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 5 Administrative Personnel 1 2011-01-01 2011-01-01 false Agent to receive process. 581.201 Section 581.201 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS PROCESSING GARNISHMENT ORDERS FOR CHILD SUPPORT AND/OR ALIMONY Service of Process § 581.201 Agent to receive process. (a...

  4. 5 CFR 582.201 - Agent to receive process.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 5 Administrative Personnel 1 2011-01-01 2011-01-01 false Agent to receive process. 582.201 Section 582.201 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS COMMERCIAL GARNISHMENT OF FEDERAL EMPLOYEES' PAY Service of Legal Process § 582.201 Agent to receive process. (a) Except...

  5. 5 CFR 581.201 - Agent to receive process.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 5 Administrative Personnel 1 2013-01-01 2013-01-01 false Agent to receive process. 581.201 Section 581.201 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS PROCESSING GARNISHMENT ORDERS FOR CHILD SUPPORT AND/OR ALIMONY Service of Process § 581.201 Agent to receive process. (a...

  6. 5 CFR 582.201 - Agent to receive process.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 5 Administrative Personnel 1 2013-01-01 2013-01-01 false Agent to receive process. 582.201 Section 582.201 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS COMMERCIAL GARNISHMENT OF FEDERAL EMPLOYEES' PAY Service of Legal Process § 582.201 Agent to receive process. (a) Except...

  7. Gambling problems and health functioning in individuals receiving disability.

    PubMed

    Morasco, Benjamin J; Petry, Nancy M

    2006-05-30

    This study evaluated the rates and correlates of disordered gambling, with a focus on gambling behavior among participants receiving disability. The sample consisted of 723 patients seeking free or reduced-cost dental care. Participants completed the South Oaks Gambling Screen (SOGS), Short Form-12 Health Survey, Second Edition (SF-12v2), and questions assessing demographic characteristics and frequency and intensity of current gambling behaviors. Results indicate a significantly higher prevalence of disordered gambling among participants receiving disability (26%) than in the remainder of the sample (14%; p < 0.001). Of the 135 individuals receiving disability, disordered gambling was associated with decreased physical and mental health functioning. These data indicate that individuals receiving disability have high rates of disordered gambling, and gambling behavior in this population is associated with poorer health functioning. Results suggest that disordered gamblers who receive disability have an increased need for interventions to reduce gambling and associated problems.

  8. Dual-Polarization, Sideband-Separating, Balanced Receiver for 1.5 THz

    NASA Technical Reports Server (NTRS)

    Chattopadhyay, Goutman; Ward, John; Manohara, Harish; Siegel, Peter

    2009-01-01

    A proposed heterodyne receiver would be capable of detecting electromagnetic radiation in both of two orthogonal linear polarizations, separating sidebands, and providing balanced outputs in a frequency band centered at 1.5 THz with a fractional bandwidth greater than 40 percent. Dual polarization, sideband-separating, and balanced-output receivers are well-known and have been used extensively at frequencies up to about 100 GHz; and there was an earlier proposal for such a receiver for frequencies up to 900 GHz. However, the present proposal represents the first realistic design concept for such a receiver capable of operating above 1 THz. The proposed receiver is intended to be a prototype of mass-producible receiver units, operating at frequencies up to 6 THz, that would be incorporated into highly sensitive heterodyne array instruments to be used in astronomical spectroscopic and imaging studies.

  9. Benefits of Software GPS Receivers for Enhanced Signal Processing

    DTIC Science & Technology

    2000-01-01

    1 Published in GPS SOLUTIONS 4(1) Summer, 2000, pages 56-66. Benefits of Software GPS Receivers for Enhanced Signal Processing Alison Brown...Diego, CA 92110-3127 Number of Pages: 24 Number of Figures: 20 ABSTRACT In this paper the architecture of a software GPS receiver is described...and an analysis is included of the performance of a software GPS receiver when tracking the GPS signals in challenging environments. Results are

  10. New type of nonglossy image-receiving sheet

    NASA Astrophysics Data System (ADS)

    Aono, Toshiaki; Shibata, Takeshi; Nakamura, Yoshisada

    1990-07-01

    We have developed a new type of non-glossy surface of an image receiving sheet for a photothermographic color hardcopy system. There is a basic conflict in realizing uniform dye transfer with use of a receiving sheet having a matted surface, because when the degree of roughness exceeds a certain extent, uneven dye transfer readily takes place. It: has been solved by use of "microscopic" phase separation of a certain water-soluble polymer blend which constitutes the surface layer of the image receiving sheet. One of the preferable polymer blends for our purpose proved to be a ternary system, consisting of sodium salt of polymethacrylic acid (PMAA-Na), ammonium salt of polyacrylic acid (PAA-NH4) and water. Phase separation, which proceeded during the evaporation of water from the coated mixture, turned out to be of a spinodal decomposition type and thus capable of stably providing a desirable non-glossy surface.

  11. 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.

  12. SCaN Network Ground Station Receiver Performance for Future Service Support

    NASA Technical Reports Server (NTRS)

    Estabrook, Polly; Lee, Dennis; Cheng, Michael; Lau, Chi-Wung

    2012-01-01

    Objectives: Examine the impact of providing the newly standardized CCSDS Low Density Parity Check (LDPC) codes to the SCaN return data service on the SCaN SN and DSN ground stations receivers: SN Current Receiver: Integrated Receiver (IR). DSN Current Receiver: Downlink Telemetry and Tracking (DTT) Receiver. Early Commercial-Off-The-Shelf (COTS) prototype of the SN User Service Subsystem Component Replacement (USS CR) Narrow Band Receiver. Motivate discussion of general issues of ground station hardware design to enable simple and cheap modifications for support of future services.

  13. 7 CFR 981.472 - Report of almonds received.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Report of almonds received. 981.472 Section 981.472... Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE ALMONDS GROWN IN CALIFORNIA Administrative Rules and Regulations § 981.472 Report of almonds received. (a) Each handler shall report to the...

  14. Thermal State-of-Charge in Solar Heat Receivers

    NASA Technical Reports Server (NTRS)

    Hall, Carsie A., Jr.; Glakpe, Emmanuel K.; Cannon, Joseph N.; Kerslake, Thomas W.

    1998-01-01

    A theoretical framework is developed to determine the so-called thermal state-of-charge (SOC) in solar heat receivers employing encapsulated phase change materials (PCMS) that undergo cyclic melting and freezing. The present problem is relevant to space solar dynamic power systems that would typically operate in low-Earth-orbit (LEO). The solar heat receiver is integrated into a closed-cycle Brayton engine that produces electric power during sunlight and eclipse periods of the orbit cycle. The concepts of available power and virtual source temperature, both on a finite-time basis, are used as the basis for determining the SOC. Analytic expressions for the available power crossing the aperture plane of the receiver, available power stored in the receiver, and available power delivered to the working fluid are derived, all of which are related to the SOC through measurable parameters. Lower and upper bounds on the SOC are proposed in order to delineate absolute limiting cases for a range of input parameters (orbital, geometric, etc.). SOC characterization is also performed in the subcooled, two-phase, and superheat regimes. Finally, a previously-developed physical and numerical model of the solar heat receiver component of NASA Lewis Research Center's Ground Test Demonstration (GTD) system is used in order to predict the SOC as a function of measurable parameters.

  15. Natural interference phenomena affecting spaceborne receivers

    NASA Technical Reports Server (NTRS)

    Stacey, J. M.

    1984-01-01

    Earth orbiting microwave receivers which are vulnerable to the interference from natural sources, mainly, the Sun and the Moon, are discussed. The irradiance from the Sun affects microwave receivers in two ways: (1) the infrared component of the irradiance causes nonuniform heating in metal structures and produces distortions that affect electrical performance; and (2) the graybody radiation component of the solar irradiance enters the collecting aperture of the antenna and the feed ports of the calibration circuits. The graybody radiation operates to degrade the signal to noise ratios and vitiate the internal calibration accuracy. The magnitudes of interference from the Sun and the Moon are analyzed and mathematical expressions are derived which serve to quantify the expected interference levels.

  16. 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.

  17. Micropower RF transponder with superregenerative receiver and RF receiver with sampling mixer

    DOEpatents

    McEwan, Thomas E.

    1997-01-01

    A micropower RF transdponder employs a novel adaptation of the superregenerative receiver wherein the quench oscillator is external to the regenerative transistor. The quench oscillator applies an exponentially decaying waveform rather than the usual sinewave to achieve high sensitivity at microampere current levels. Further improvements include circuit simplifications for antenna coupling, extraction of the detected signal, and a low-voltage bias configuration that allows operation with less than a 1-volt rail voltage. The inventive transponder is expected to operate as long as the battery shelf life.

  18. The Sender-Receiver Model and the Targeting Process.

    ERIC Educational Resources Information Center

    Larson, Mark A.

    The goal of this paper is to describe how one classroom teacher uses the Sender-Receiver Communications Model to illustrate for students in a lively and memorable way the process of "targeting your audience" with medium and message. Students are used as examples of Receivers, or target audience, illustrating the potential range of…

  19. 12 CFR 614.4700 - Financing foreign trade receivables.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 12 Banks and Banking 6 2011-01-01 2011-01-01 false Financing foreign trade receivables. 614.4700 Section 614.4700 Banks and Banking FARM CREDIT ADMINISTRATION FARM CREDIT SYSTEM LOAN POLICIES AND OPERATIONS Banks for Cooperatives and Agricultural Credit Banks Financing International Trade § 614.4700 Financing foreign trade receivables. (a) Banks...

  20. 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.

  1. 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.

  2. Design for On-Sun Evaluation of Evaporator Receivers

    NASA Technical Reports Server (NTRS)

    Jaworske, Donald A.; Colozza, Anthony; Sechkar, Edward A.

    2011-01-01

    A heat pipe designed for operation as a solar power receiver should be optimized to accept the solar energy flux and transfer this heat into a reactor. Optical properties of the surface, thermal conductance of the receiver wall, contact resistance of the heat pipe wick, and other heat pipe wick properties ultimately define the maximum amount of power that can be extracted from the concentrated sunlight impinging on the evaporator surface. Modeling of solar power receivers utilizing optical and physical properties provides guidance to their design. On-sun testing is another important means of gathering information on performance. A test rig is being designed and built to conduct on-sun testing. The test rig is incorporating a composite strip mirror concentrator developed as part of a Small Business Innovative Research effort and delivered to NASA Glenn Research Center. In the strip concentrator numerous, lightweight composite parabolic strips of simple curvature were combined to form an array 1.5 m x 1.5 m in size. The line focus of each strip is superimposed in a central area simulating a point of focus. A test stand is currently being developed to hold the parabolic strip concentrator, track the sun, and turn the beam downward towards the ground. The hardware is intended to be sufficiently versatile to accommodate on-sun testing of several receiver concepts, including those incorporating heat pipe evaporators. Characterization devices are also being developed to evaluate the effectiveness of the solar concentrator, including a receiver designed to conduct calorimetry. This paper describes the design and the characterization devices of the on-sun test rig, and the prospect of coupling the concentrated sunlight to a heat pipe solar power receiver developed as part of another Small Business Innovative Research effort.

  3. Receiver function deconvolution using transdimensional hierarchical Bayesian inference

    NASA Astrophysics Data System (ADS)

    Kolb, J. M.; Lekić, V.

    2014-06-01

    Teleseismic waves can convert from shear to compressional (Sp) or compressional to shear (Ps) across impedance contrasts in the subsurface. Deconvolving the parent waveforms (P for Ps or S for Sp) from the daughter waveforms (S for Ps or P for Sp) generates receiver functions which can be used to analyse velocity structure beneath the receiver. Though a variety of deconvolution techniques have been developed, they are all adversely affected by background and signal-generated noise. In order to take into account the unknown noise characteristics, we propose a method based on transdimensional hierarchical Bayesian inference in which both the noise magnitude and noise spectral character are parameters in calculating the likelihood probability distribution. We use a reversible-jump implementation of a Markov chain Monte Carlo algorithm to find an ensemble of receiver functions whose relative fits to the data have been calculated while simultaneously inferring the values of the noise parameters. Our noise parametrization is determined from pre-event noise so that it approximates observed noise characteristics. We test the algorithm on synthetic waveforms contaminated with noise generated from a covariance matrix obtained from observed noise. We show that the method retrieves easily interpretable receiver functions even in the presence of high noise levels. We also show that we can obtain useful estimates of noise amplitude and frequency content. Analysis of the ensemble solutions produced by our method can be used to quantify the uncertainties associated with individual receiver functions as well as with individual features within them, providing an objective way for deciding which features warrant geological interpretation. This method should make possible more robust inferences on subsurface structure using receiver function analysis, especially in areas of poor data coverage or under noisy station conditions.

  4. Solar central receiver reformer system for ammonia plants

    NASA Astrophysics Data System (ADS)

    1980-07-01

    Details of the conceptual design, economic analysis, and development plan for a solar central receiver system for retrofitting the Valley Nitrogen Producers, Inc., El Centro, California 600 ST/SD Ammonia Plant are presented. The retrofit system consists of a solar central receiver reformer (SCRR) operating in parallel with the existing fossil fired reformer. Steam and hydrocarbon react in the catalyst filled tubes of the inner cavity receiver to form a hydrogen rich mixture which is the syngas feed for the ammonia production. The SCRR system displaces natural gas presently used in the fossil reformer combustion chamber. The solar reformer retrofit system characteristics and its interface with the existing plant are simple, incorporating state of the art components with proven technology. A northfield composed of one thousand forty second generation heliostats provides solar energy to the receiver which is positioned on top of a 90 meter high steel tower. The overall economics of this system can provide over 20% discount cash flow rate of return with proper investment and market conditions.

  5. 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.

  6. 10 CFR 20.1906 - Procedures for receiving and opening packages.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 1 2014-01-01 2014-01-01 false Procedures for receiving and opening packages. 20.1906 Section 20.1906 Energy NUCLEAR REGULATORY COMMISSION STANDARDS FOR PROTECTION AGAINST RADIATION... received at the licensee's facility if it is received during the licensee's normal working hours, or not...

  7. 10 CFR 20.1906 - Procedures for receiving and opening packages.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 1 2013-01-01 2013-01-01 false Procedures for receiving and opening packages. 20.1906 Section 20.1906 Energy NUCLEAR REGULATORY COMMISSION STANDARDS FOR PROTECTION AGAINST RADIATION... received at the licensee's facility if it is received during the licensee's normal working hours, or not...

  8. 10 CFR 20.1906 - Procedures for receiving and opening packages.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 1 2010-01-01 2010-01-01 false Procedures for receiving and opening packages. 20.1906 Section 20.1906 Energy NUCLEAR REGULATORY COMMISSION STANDARDS FOR PROTECTION AGAINST RADIATION... received at the licensee's facility if it is received during the licensee's normal working hours, or not...

  9. 10 CFR 20.1906 - Procedures for receiving and opening packages.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 1 2012-01-01 2012-01-01 false Procedures for receiving and opening packages. 20.1906 Section 20.1906 Energy NUCLEAR REGULATORY COMMISSION STANDARDS FOR PROTECTION AGAINST RADIATION... received at the licensee's facility if it is received during the licensee's normal working hours, or not...

  10. 10 CFR 20.1906 - Procedures for receiving and opening packages.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 1 2011-01-01 2011-01-01 false Procedures for receiving and opening packages. 20.1906 Section 20.1906 Energy NUCLEAR REGULATORY COMMISSION STANDARDS FOR PROTECTION AGAINST RADIATION... received at the licensee's facility if it is received during the licensee's normal working hours, or not...

  11. Behavior Disorders in Persons with Mental Retardation Receiving Antipsychotic Medication.

    ERIC Educational Resources Information Center

    Ono, Yoshiro

    1998-01-01

    The behavior disorders of 54 Japanese individuals with mental retardation receiving antipsychotic medication were compared to 52 subjects receiving anticonvulsants and 202 subjects without medication. Results found the problem behaviors of subjects receiving antipsychotic drugs were more severe and severity of disability was associated with higher…

  12. 47 CFR 87.151 - Special requirements for differential GPS receivers.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 5 2011-10-01 2011-10-01 false Special requirements for differential GPS receivers. 87.151 Section 87.151 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND... differential GPS receivers. (a) The receiver shall achieve a message failure rate less than or equal to one...

  13. Communications Satellite Receiver Systems for Public Schools: A Technical Primer.

    ERIC Educational Resources Information Center

    Texas Education Agency, Austin.

    Designed to aid school districts contemplating use of some of the telecommunications services now available by satellite, this document contains information on home satellite receiving dishes (Television Receive-Only--TVROs), which can receive radio signals carrying television, sound, and data. This information includes: some factors involved in…

  14. Testing the Grandchildren's Received Affection Scale using Affection Exchange Theory.

    PubMed

    Mansson, Daniel H

    2013-04-01

    The purpose of this study was to test the Grandchildren's Received Affection Scale (GRAS) using Affection Exchange Theory (Floyd, 2006). In accordance with Affection Exchange Theory, it was hypothesized that grandchildren's scores on the Trait Affection Received Scale (i.e., the extent to which individuals by nature receive affection) would be related significantly and positively to their reports of received affection from their grandparents (i.e., their scores on the GRAS). Additionally, a research question was asked to explore if grandchildren's received affection from their grandparents is dependent on their grandparent's biological sex or lineage (i.e., maternal vs paternal). Thus, young adult grandchildren (N = 422) completed the GRAS and the Trait Affection Received Scale. The results of zero-order Pearson correlational analyses provided support for the hypothesis, whereas the results of MANOVAs tests only partially support extant grandparent-grandchild theory and research. These findings broaden the scope of Affection Exchange Theory and also bolster the GRAS's utility in future grandparent-grandchild affectionate communication research.

  15. A low noise 665 GHz SIS quasi-particle waveguide receiver

    NASA Technical Reports Server (NTRS)

    Kooi, J. W.; Walker, C. K.; Leduc, H. G.; Hunter, T. R.; Benford, D. J.; Phillips, T. G.

    1993-01-01

    Recent results on a 565-690 GHz SIS heterodyne receiver employing a 0.36 micron(sup 2) Nb/AlOx/Nb SIS tunnel junction with high quality circular non-contacting back short and E-plane tuners in a full height wave guide mount are reported. No resonant tuning structures were incorporated in the junction design at this time, even though such structures are expected to help the performance of the receiver. The receiver operates to at least the gap frequency of Niobium, approximately 680 GHz. Typical receiver noise temperatures from 565-690 GHz range from 160K to 230K with a best value of 185K DSB at 648 GHz. With the mixer cooled from 4.3K to 2K the measured receiver noise temperatures decreased by approximately 15 percent, giving roughly 180K DSB from 660 to 680 GHz. The receiver has a full 1 GHz IF pass band and was successfully installed at the Caltech Submillimeter Observatory in Hawaii.

  16. Advanced development receiver thermal vacuum tests with cold wall

    NASA Technical Reports Server (NTRS)

    Sedgwick, Leigh M.

    1991-01-01

    The first ever testing of a full size solar dynamic heat receiver using high temperature thermal energy storage was completed. The heat receiver was designed to meet the requirements for operation on the Space Station Freedom. The purpose of the test program was to quantify the receiver thermodynamic performance, its operating temperatures, and thermal response to changes in environmental and power module interface boundary conditions. The heat receiver was tested in a vacuum chamber with liquid nitrogen cold shrouds and an aperture cold plate to partially simulate a low Earth orbit environment. The cavity of the receiver was heated by an infrared quartz lamp heater with 30 independently controllable zones to produce flux distributions typical of candidate concentrators. A closed Brayton cycle engine simulator conditioned a helium xenon gas mixture to specific interface conditions to simulate various operational modes of the solar dynamic power module. Inlet gas temperature, pressure, and flow rate were independently varied. A total of 58 simulated orbital cycles were completed during the test conduct period. The test hardware, execution of testing, test data, and post test inspections are described.

  17. Hybrid Analog/Digital Receiver

    NASA Technical Reports Server (NTRS)

    Brown, D. H.; Hurd, W. J.

    1989-01-01

    Advanced hybrid analog/digital receiver processes intermediate-frequency (IF) signals carrying digital data in form of phase modulation. Uses IF sampling and digital phase-locked loops to track carrier and subcarrier signals and to synchronize data symbols. Consists of three modules: IF assembly, signal-processing assembly, and test-signal assembly. Intended for use in Deep Space Network, but presumably basic design modified for such terrestrial uses as communications or laboratory instrumentation where signals weak and/or noise strong.

  18. Measuring Balance Across Multiple Radar Receiver Channels.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Doerry, Armin W.; Bickel, Douglas L.

    When radar receivers employ multiple channels, the general intent is for the receive channels to be as alike as possible, if not as ideal as possible. This is usually done via prudent hardware design, supplemented by system calibration. Towards this end, we require a quality metric for ascertaining the goodness of a radar channel, and the degree of match to sibling channels. We propose a relevant and useable metric to do just that. Acknowledgements This report was the result of an unfunded research and development activity.

  19. 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.

  20. Suppression of Interchannel Interference in FM Receivers

    DTIC Science & Technology

    1979-07-01

    construed as an official Depart- ment of the Army position, unlessa so designated by other authorized docum ents. 19. KE£Y WORiZS (Centinae an toeva side...receiver structure is derived. Then, experimental results on a detector designed by copying the topology of the optimum receiver structure are...and autocorrelation Rm (T) and R (T). We designate t xl(t) = J rl(u) du (2) -t Xz(t) m n(u)du (3) This converts the FM waves s1(t) and s,(t) into

  1. Simplified Calculation Of Solar Fluxes In Solar Receivers

    NASA Technical Reports Server (NTRS)

    Bhandari, Pradeep

    1990-01-01

    Simplified Calculation of Solar Flux Distribution on Side Wall of Cylindrical Cavity Solar Receivers computer program employs simple solar-flux-calculation algorithm for cylindrical-cavity-type solar receiver. Results compare favorably with those of more complicated programs. Applications include study of solar energy and transfer of heat, and space power/solar-dynamics engineering. Written in FORTRAN 77.

  2. Micropower RF transponder with superregenerative receiver and RF receiver with sampling mixer

    DOEpatents

    McEwan, T.E.

    1997-05-13

    A micropower RF transponder employs a novel adaptation of the superregenerative receiver wherein the quench oscillator is external to the regenerative transistor. The quench oscillator applies an exponentially decaying waveform rather than the usual sinewave to achieve high sensitivity at microampere current levels. Further improvements include circuit simplifications for antenna coupling, extraction of the detected signal, and a low-voltage bias configuration that allows operation with less than a 1-volt rail voltage. The inventive transponder is expected to operate as long as the battery shelf life. 13 figs.

  3. 47 CFR 11.56 - EAS Participants receive CAP-formatted alerts.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 1 2010-10-01 2010-10-01 false EAS Participants receive CAP-formatted alerts... SYSTEM (EAS) Emergency Operations § 11.56 EAS Participants receive CAP-formatted alerts. Notwithstanding anything herein to the contrary, all EAS Participants must be able to receive CAP-formatted EAS alerts no...

  4. CESA-1 receiver design review. Phase 1. Final report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1980-07-01

    The Central Electrica Solar de Almeria CESA-1 is a 1.0 MWe water/steam solar central receiver electric power plant being built by the Spanish in Almeria, Spain. Centro de Estudios de la Energia (CEE) is responsible for the management, design, and construction of the project. At the request of the Solar Energy Research Institute and with the approval of the Department of Energy, Sandia National Laboratories, Livermore is providing technical assistance in areas unique to solar applications to CEE. At the request of CEE, Sandia contracted with Foster Wheeler Development Corporation (FWDC) to critically review and evaluate the CESA-1 receiver design.more » Foster Wheeler Iberia (FWI) was subcontracted to FWDC to coordinate efforts with CEE in Madrid. The FWDC program which was started on July 9, 1979, was subdivided into three tasks: (1) design basis review: critical review of the receiver design specifications and requirements; (2) design review and analyses: critical review of thermal/hydraulic, structural, and materials aspects of the receiver design and the design and analysis procedures used by the designer in critical areas of the design; and (3) operational review: critical review of receiver instrumentation and controls and the operational and safety aspects of the receiver. Results of the design review and evaluation are presented. (WHK)« less

  5. High-k Scattering Receiver Mixer Performance for NSTX-U

    NASA Astrophysics Data System (ADS)

    Barchfeld, Robert; Riemenschneider, Paul; Domier, Calvin; Luhmann, Neville; Ren, Yang; Kaita, Robert

    2016-10-01

    The High-k Scattering system detects primarily electron-scale turbulence k θ spectra for studying electron thermal transport in NSTX-U. A 100 mW, 693 GHz probe beam passes through plasma, and scattered power is detected by a 4-pixel quasi optical, mixer array. Remotely controlled receiving optics allows the scattering volume to be located from core to edge with a k θ span of 7 to 40 cm-1. The receiver array features 4 RF diagonal input horns, where the electric field polarization is aligned along the diagonal of a square cross section horn, at 30 mm channel spacing. The local oscillator is provided by a 14.4 GHz source followed by a x48 multiplier chain, giving an intermediate frequency of 1 GHz. The receiver optics receive 4 discreet scattering angles simultaneously, and then focus the signals as 4 parallel signals to their respective horns. A combination of a steerable probe beam, and translating receiver, allows for upward or downward scattering which together can provide information about 2D turbulence wavenumber spectrum. IF signals are digitized and stored for later computer analysis. The performance of the receiver mixers is discussed, along with optical design features to enhance the tuning and performance of the mixers. Work supported in part by U.S. DOE Grant DE-FG02-99ER54518 and DE-AC02-09CH1146.

  6. Health Research Participants’ Preferences for Receiving Research Results

    PubMed Central

    Long, Christopher R.; Stewart, M. Kathryn; Cunningham, Thomas V.; Warmack, T. Scott; McElfish, Pearl A.

    2017-01-01

    Background Participants in health research studies typically express interest in receiving results from the studies in which they participate. However, participants’ preferences and experiences related to receiving results are not well understood. In general, existing studies have had relatively small sample sizes and typically address specific and often sensitive issues within targeted populations. Methods The present study used an online survey to explore attitudes and experiences of registrants in ResearchMatch, a large database of past, present, and potential health research participants. Survey respondents provided information related to whether or not they received research results from studies in which they participated, the methods used to communicate results, their satisfaction with results, and when and how they would like to receive research results from future studies. 70,699 ResearchMatch registrants were notified of the study’s topic. Of the 5,207 registrants who requested full information about the study, 3,381 respondents completed the survey. Results Approximately 33% of respondents with previous health research participation reported receiving results. Approximately half of respondents with previous research participation reported no opportunity to request results. However, almost all respondents said researchers should always or sometimes offer results to participants. Respondents expressed particular interest in results related to their (or a loved one's) health, as well as information about studies’ purposes and any medical advances based on the results. In general, respondents’ most preferred dissemination methods for results were email and website postings. The least desirable dissemination methods for results included Twitter, conference calls, and text messages. Across all results, we compare the responses of respondents with and without previous research participation experience, and those who have worked in research organizations

  7. Health research participants' preferences for receiving research results.

    PubMed

    Long, Christopher R; Stewart, M Kathryn; Cunningham, Thomas V; Warmack, T Scott; McElfish, Pearl A

    2016-12-01

    Participants in health research studies typically express interest in receiving the results from the studies in which they participate. However, participants' preferences and experiences related to receiving the results are not well understood. In general, the existing studies have had relatively small sample sizes and typically address specific and often sensitive issues within targeted populations. This study used an online survey to explore attitudes and experiences of registrants in ResearchMatch, a large database of past, present, and potential health research participants. Survey respondents provided information related to whether or not they received research results from studies in which they participated, the methods used to communicate the results, their satisfaction with the results, and when and how they would like to receive research results from future studies. In all, 70,699 ResearchMatch registrants were notified of the study's topic. Of the 5207 registrants who requested full information about the study, 3381 respondents completed the survey. Approximately 33% of respondents with previous health research participation reported receiving the results. Approximately half of respondents with previous research participation reported no opportunity to request the results. However, almost all respondents said researchers should always or sometimes offer the results to participants. Respondents expressed particular interest in the results related to their (or a loved one's) health, as well as information about studies' purposes and any medical advances based on the results. In general, respondents' most preferred dissemination methods for the results were email and website postings. The least desirable dissemination methods for the results included Twitter, conference calls, and text messages. Across all the results, we compare the responses of respondents with and without previous research participation experience and those who have worked in research

  8. Design and implementation of a low-power SOI CMOS receiver

    NASA Astrophysics Data System (ADS)

    Zencir, Ertan

    There is a strong demand for wireless communications in civilian and military applications, and space explorations. This work attempts to implement a low-power, high-performance fully-integrated receiver for deep space communications using Silicon on Insulator (SOI) CMOS technology. Design and implementation of a UHF low-IF receiver front-end in a 0.35-mum SOI CMOS technology are presented. Problems and challenges in implementing a highly integrated receiver at UHF are identified. Low-IF architecture, suitable for low-power design, has been adopted to mitigate the noise at the baseband. Design issues of the receiver building blocks including single-ended and differential LNA's, passive and active mixers, and variable gain/bandwidth complex filters are discussed. The receiver is designed to have a variable conversion gain of more than 100 dB with a 70 dB image rejection and a power dissipation of 45 mW from a 2.5-V supply. Design and measured performance of the LNA's, and the mixer are presented. Measurement results of RF front-end blocks including a single-ended LNA, a differential LNA, and a double-balanced mixer demonstrate the low power realizability of RF front-end circuits in SOI CMOS technology. We also report on the design and simulation of the image-rejecting complex IF filter and the full receiver circuit. Gain, noise, and linearity performance of the receiver components prove the viability of fully integrated low-power receivers in SOI CMOS technology.

  9. Multi-Gnss Receiver for Aerospace Navigation and Positioning Applications

    NASA Astrophysics Data System (ADS)

    Peres, T. R.; Silva, J. S.; Silva, P. F.; Carona, D.; Serrador, A.; Palhinha, F.; Pereira, R.; Véstias, M.

    2014-03-01

    The upcoming Galileo system opens a wide range of new opportunities in the Global Navigation Satellite System (GNSS) market. However, the characteristics of the future GNSS signals require the development of new GNSS receivers. In the frame of the REAGE project, DEIMOS and ISEL have developed a GNSS receiver targeted for aerospace applications, supporting current and future GPS L1 and Galileo E1 signals, based on commercial (or, in the furthest extent, industrial) grade components. Although the REAGE project aimed at space applications, the REAGE receiver is also applicable to many terrestrial applications (ground or airborne), such as Georeferencing and Unmanned Aerial Vehicle (UAV) navigation. This paper presents the architecture and features of the REAGE receiver, as well as some results of the validation campaign with GPS L1 and Galileo E1 signals.

  10. Dynamic detailed model of a molten salt tower receiver, with ThermoSysPro library: Impacts of several failures or operational transients on the receiver dynamic behavior

    NASA Astrophysics Data System (ADS)

    Hefni, Baligh El; Bourdil, Charles

    2017-06-01

    Molten salt technology represents nowadays the most cost-effective technology for electricity generation for solar power plant. The molten salt tower receiver is based on a field of individually sun-tracking mirrors (heliostats) that reflect the incident sunshine to a receiver at the top of a centrally located tower. The objective of this study is to assess the impact of several transients issued from different scenarios (failure or normal operation mode) on the receiver dynamic behavior. A dynamic detailed model of Solar Two molten salt central receiver has been developed. The component model is meant to be used for receiver modeling with the ThermoSysPro library, developed by EDF. The paper also gives the results of the dynamic simulation for the selected scenarios on Solar Two receiver.

  11. SEPIA - a new single pixel receiver at the APEX telescope

    NASA Astrophysics Data System (ADS)

    Belitsky, V.; Lapkin, I.; Fredrixon, M.; Meledin, D.; Sundin, E.; Billade, B.; Ferm, S.-E.; Pavolotsky, A.; Rashid, H.; Strandberg, M.; Desmaris, V.; Ermakov, A.; Krause, S.; Olberg, M.; Aghdam, P.; Shafiee, S.; Bergman, P.; Beck, E. De; Olofsson, H.; Conway, J.; Breuck, C. De; Immer, K.; Yagoubov, P.; Montenegro-Montes, F. M.; Torstensson, K.; Pérez-Beaupuits, J.-P.; Klein, T.; Boland, W.; Baryshev, A. M.; Hesper, R.; Barkhof, J.; Adema, J.; Bekema, M. E.; Koops, A.

    2018-04-01

    Context. We describe the new Swedish-ESO PI Instrument for APEX (SEPIA) receiver, which was designed and built by the Group for Advanced Receiver Development (GARD), at Onsala Space Observatory (OSO) in collaboration with ESO. It was installed and commissioned at the APEX telescope during 2015 with an ALMA Band 5 receiver channel and updated with a new frequency channel (ALMA Band 9) in February 2016. Aim. This manuscript aims to provide, for observers who use the SEPIA receiver, a reference in terms of the hardware description, optics and performance as well as the commissioning results. Methods: Out of three available receiver cartridge positions in SEPIA, the two current frequency channels, corresponding to ALMA Band 5, the RF band 158-211 GHz, and Band 9, the RF band 600-722 GHz, provide state-of-the-art dual polarization receivers. The Band 5 frequency channel uses 2SB SIS mixers with an average SSB noise temperature around 45 K with IF (intermediate frequency) band 4-8 GHz for each sideband providing total 4 × 4 GHz IF band. The Band 9 frequency channel uses DSB SIS mixers with a noise temperature of 75-125 K with IF band 4-12 GHz for each polarization. Results: Both current SEPIA receiver channels are available to all APEX observers.

  12. 12 CFR 650.20 - Powers and duties of the receiver.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... assist the receiver) and all costs of carrying out or exercising the rights, powers, privileges, and... 12 Banks and Banking 6 2011-01-01 2011-01-01 false Powers and duties of the receiver. 650.20... MORTGAGE CORPORATION GENERAL PROVISIONS § 650.20 Powers and duties of the receiver. (a) General. (1) Upon...

  13. 12 CFR 650.20 - Powers and duties of the receiver.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... assist the receiver) and all costs of carrying out or exercising the rights, powers, privileges, and... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Powers and duties of the receiver. 650.20... MORTGAGE CORPORATION GENERAL PROVISIONS § 650.20 Powers and duties of the receiver. (a) General. (1) Upon...

  14. 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.

  15. 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

  16. Low Noise 1.2 THz SIS Receiver

    NASA Technical Reports Server (NTRS)

    Karpov, A.; Miller, D.; Rice, F.; Zmuidzinas, J.; Stern, J. A.; Bumble, B.; LeDuc, H. G.

    2001-01-01

    We present the development of a low noise superconductor insulator superconductor (SIS) mixer for the 1.1 - 1.25 THz heterodyne receiver of FIRST space radiotelescope. The quasi-optical SIS mixer has two NbTiN/AlN/Nb junctions with critical current density 30 kA/sq cm. The individual junction area is close to 0.65 square micrometers. The SIS junctions are coupled to the optical input beam through a planar double slot antenna and a Si hyperhemispherical lens. The minimum DSB receiver noise temperature is 650 K, about 12 hv/k.

  17. Are the Right Students Receiving Need Based Federal Student Financial Aid

    ERIC Educational Resources Information Center

    Kennedy, Joseph

    2009-01-01

    Students at a college or university who receive need-based financial aid, receive a tremendous financial resource compared to those students who do not receive need based financial aid. A sample of 100 students from various backgrounds and skills were surveyed. The survey asked questions of the two student groups: received need based financial aid…

  18. Impact of donor-specific HLA antibodies in transplantation, a review of the literature published in the last three years.

    PubMed

    Kaneku, Hugo

    2010-01-01

    This chapter summarizes some of the recent findings published on the role in organ transplantation of HLA antibodies, and--more important--donor-specific HLA antibodies. The negative impact of both, preformed and de novo DSA is now better recognized in recipients of kidney, heart, lung, liver, pancreas, islet cells and bone marrow transplants. An appropriate design of a schedule to monitor HLA antibodies may identify patients at higher risk for immunological events earlier and allow interventions to avoid later graft loss. The value of strategies like preemptive treatment of antibodies and the use of new agents like bortezomib and eculizumab are of interest and need further investigation.

  19. Receiver function analysis applied to refraction survey data

    NASA Astrophysics Data System (ADS)

    Subaru, T.; Kyosuke, O.; Hitoshi, M.

    2008-12-01

    For the estimation of the thickness of oceanic crust or petrophysical investigation of subsurface material, refraction or reflection seismic exploration is one of the methods frequently practiced. These explorations use four-component (x,y,z component of acceleration and pressure) seismometer, but only compressional wave or vertical component of seismometers tends to be used in the analyses. Hence, it is needed to use shear wave or lateral component of seismograms for more precise investigation to estimate the thickness of oceanic crust. Receiver function is a function at a place that can be used to estimate the depth of velocity interfaces by receiving waves from teleseismic signal including shear wave. Receiver function analysis uses both vertical and horizontal components of seismograms and deconvolves the horizontal with the vertical to estimate the spectral difference of P-S converted waves arriving after the direct P wave. Once the phase information of the receiver function is obtained, then one can estimate the depth of the velocity interface. This analysis has advantage in the estimation of the depth of velocity interface including Mohorovicic discontinuity using two components of seismograms when P-to-S converted waves are generated at the interface. Our study presents results of the preliminary study using synthetic seismograms. First, we use three types of geological models that are composed of a single sediment layer, a crust layer, and a sloped Moho, respectively, for underground sources. The receiver function can estimate the depth and shape of Moho interface precisely for the three models. Second, We applied this method to synthetic refraction survey data generated not by earthquakes but by artificial sources on the ground or sea surface. Compressional seismic waves propagate under the velocity interface and radiate converted shear waves as well as at the other deep underground layer interfaces. However, the receiver function analysis applied to the

  20. Co-Channel Interference Mitigation Using Satellite Based Receivers

    DTIC Science & Technology

    2014-12-01

    NAVAL POSTGRADUATE SCHOOL MONTEREY, CALIFORNIA THESIS CO-CHANNEL INTERFERENCE MITIGATION USING SATELLITE BASED RECEIVERS by John E. Patterson...07-02-2012 to 12-19-2014 4. TITLE AND SUBTITLE CO-CHANNEL INTERFERENCE MITIGATION USING SATELLITE BASED RE- CEIVERS 5. FUNDING NUMBERS 6. AUTHOR(S...Approved for public release; distribution is unlimited CO-CHANNEL INTERFERENCE MITIGATION USING SATELLITE BASED RECEIVERS John E. Patterson Commander

  1. 40 CFR 98.473 - Calculating CO2 received.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    .... (a) You must calculate and report the annual mass of CO2 received by pipeline using the procedures in... applicable. (1) For a mass flow meter, you must calculate the total annual mass of CO2 in a CO2 stream received in metric tons by multiplying the mass flow by the CO2 concentration in the flow, according to...

  2. 40 CFR 98.473 - Calculating CO2 received.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    .... (a) You must calculate and report the annual mass of CO2 received by pipeline using the procedures in... applicable. (1) For a mass flow meter, you must calculate the total annual mass of CO2 in a CO2 stream received in metric tons by multiplying the mass flow by the CO2 concentration in the flow, according to...

  3. 40 CFR 98.473 - Calculating CO2 received.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    .... (a) You must calculate and report the annual mass of CO2 received by pipeline using the procedures in... applicable. (1) For a mass flow meter, you must calculate the total annual mass of CO2 in a CO2 stream received in metric tons by multiplying the mass flow by the CO2 concentration in the flow, according to...

  4. 40 CFR 98.473 - Calculating CO2 received.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    .... (a) You must calculate and report the annual mass of CO2 received by pipeline using the procedures in... applicable. (1) For a mass flow meter, you must calculate the total annual mass of CO2 in a CO2 stream received in metric tons by multiplying the mass flow by the CO2 concentration in the flow, according to...

  5. Point-Focusing Solar-Power Distributed Receivers

    NASA Technical Reports Server (NTRS)

    Lucas, J. W.

    1985-01-01

    Two-volume annual report describes development work aimed at achieving large-scale production of modular, point-focusing distributed receivers (PFDR's) for solar-powered generation of electricity or thermal power for industrial use.

  6. Development of the Multi-Level Seismic Receiver (MLSR)

    NASA Astrophysics Data System (ADS)

    Sleefe, G. E.; Engler, B. P.; Drozda, P. M.; Franco, R. J.; Morgan, Jeff

    1995-02-01

    The Advanced Geophysical Technology Department (6114) and the Telemetry Technology Development Department (2664) have, in conjunction with the Oil Recovery Technology Partnership, developed a Multi-Level Seismic Receiver (MLSR) for use in crosswell seismic surveys. The MLSR was designed and evaluated with the significant support of many industry partners in the oil exploration industry. The unit was designed to record and process superior quality seismic data operating in severe borehole environments, including high temperature (up to 200 C) and static pressure (10,000 psi). This development has utilized state-of-the-art technology in transducers, data acquisition, and real-time data communication and data processing. The mechanical design of the receiver has been carefully modeled and evaluated to insure excellent signal coupling into the receiver.

  7. The 30 GHz communications satellite low noise receiver

    NASA Technical Reports Server (NTRS)

    Steffek, L. J.; Smith, D. W.

    1983-01-01

    A Ka-band low noise front end in proof of concept (POC) model form for ultimate spaceborne communications receiver deployment was developed. The low noise receiver consists of a 27.5 to 30.0 GHz image enhanced mixer integrated with a 3.7 to 6.2 GHz FET low noise IF amplifier and driven by a self contained 23.8 GHz phase locked local oscillator source. The measured level of receiver performance over the 27.3 to 30.0 GHz RF/3.7 to 6.2 GHz IF band includes 5.5 to 6.5 dB (typ) SSB noise figure, 20.5 + or - 1.5 dB conversion gain and +23 dBm minimum third order two tone intermodulation output intercept point.

  8. A spaceborne receiver for measuring electromagnetic field intensity

    NASA Technical Reports Server (NTRS)

    Reich, B. W.; Van Dusen, M. R.; Habib, E. J.

    1973-01-01

    Description of a very accurately controlled receiver for monitoring the electromagnetic radiations in both existing and projected space communication bands. Based on analysis of the existing and projected space communication bands, 108 to 174 MHz, 240 to 478 MHz, and 1535 to 1665 MHz were covered. The receiver achieves accurate control via a digitally tuned synthesizer and a wide range of digital control including frequency band coverage and gain control selection. Digital memory was provided to store 16 separate digital command instructions which can be programmed via a command data link. The receiver provides for transmission to the ground of both a predetection signal and signals in digital format, which in turn, were provided by sampling and analog-to-digital conversions.

  9. Social effects of migration in receiving countries.

    PubMed

    Ohndorf, W

    1989-06-01

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

  10. Performance prediction evaluation of ceramic materials in point-focusing solar receivers

    NASA Technical Reports Server (NTRS)

    Ewing, J.; Zwissler, J.

    1979-01-01

    A performance prediction was adapted to evaluate the use of ceramic materials in solar receivers for point focusing distributed applications. System requirements were determined including the receiver operating environment and system operating parameters for various engine types. Preliminary receiver designs were evolved from these system requirements. Specific receiver designs were then evaluated to determine material functional requirements.

  11. Low proportion of high school senior athletes receiving recommended immunizations.

    PubMed

    Karpinos, Ashley Rowatt; Rizzone, Katherine H; Cribbs, Sarah P; Roumie, Christianne L

    2014-05-01

    The preparticipation physical evaluation (PPE) often serves as the only preventive health care visit for athletes, but immunization status is not uniformly addressed in such visits. Thus, athletes may not be receiving recommended immunizations. Our aim was to determine the proportion of high school senior athletes who received all recommended immunizations. Our hypothesis was that females would be less likely than males to receive all recommended immunizations given suboptimal human papillomavirus (HPV) vaccine uptake. We conducted a cross-sectional survey evaluation of the immunization status of high school senior athletes in Davidson County, TN. The primary composite outcome was receipt of recommended immunizations for tetanus, meningococcal, and seasonal influenza. For females, the primary outcome also included completion of the HPV series. A total of 162 participants, 104 males and 58 females, were included. More males than females received all recommended immunizations (15.4% vs 3.5%; P = 0.02). When HPV immunization was excluded from the composite outcome, there was no difference in the proportion of males and females who received all recommended immunizations (15.4% vs 15.5%; P = 0.98). The odds of receiving all recommended immunizations was 0.14 (95% CI, 0.03-0.72) for females compared with males when adjusted for covariates. Athletes seen at retail-based clinics for their PPE were less likely to receive all recommended immunizations compared with athletes seen in primary care (OR, 0.13; 95% CI, 0.02-0.69). Only 1 in 6 high school senior athletes received the recommended tetanus, meningococcal, and influenza immunizations. A lower proportion of females, only 1 in 28, received all recommended immunizations due to the HPV series. Policy changes requiring a review of immunizations at the PPE would benefit many high school athletes.

  12. High temperature helical tubular receiver for concentrating solar power system

    NASA Astrophysics Data System (ADS)

    Hossain, Nazmul

    In the field of conventional cleaner power generation technology, concentrating solar power systems have introduced remarkable opportunity. In a solar power tower, solar energy concentrated by the heliostats at a single point produces very high temperature. Falling solid particles or heat transfer fluid passing through that high temperature region absorbs heat to generate electricity. Increasing the residence time will result in more heat gain and increase efficiency. A novel design of solar receiver for both fluid and solid particle is approached in this paper which can increase residence time resulting in higher temperature gain in one cycle compared to conventional receivers. The helical tubular solar receiver placed at the focused sunlight region meets the higher outlet temperature and efficiency. A vertical tubular receiver is modeled and analyzed for single phase flow with molten salt as heat transfer fluid and alloy625 as heat transfer material. The result is compared to a journal paper of similar numerical and experimental setup for validating our modeling. New types of helical tubular solar receivers are modeled and analyzed with heat transfer fluid turbulent flow in single phase, and granular particle and air plug flow in multiphase to observe the temperature rise in one cyclic operation. The Discrete Ordinate radiation model is used for numerical analysis with simulation software Ansys Fluent 15.0. The Eulerian granular multiphase model is used for multiphase flow. Applying the same modeling parameters and boundary conditions, the results of vertical and helical receivers are compared. With a helical receiver, higher temperature gain of heat transfer fluid is achieved in one cycle for both single phase and multiphase flow compared to the vertical receiver. Performance is also observed by varying dimension of helical receiver.

  13. 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

  14. 25 CFR 20.332 - Who can receive Adult Care Assistance?

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Who can receive Adult Care Assistance? 20.332 Section 20... AND SOCIAL SERVICES PROGRAMS Direct Assistance Adult Care Assistance § 20.332 Who can receive Adult Care Assistance? An adult Indian is eligible to receive adult care assistance under this part if he/she...

  15. 25 CFR 20.332 - Who can receive Adult Care Assistance?

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 25 Indians 1 2014-04-01 2014-04-01 false Who can receive Adult Care Assistance? 20.332 Section 20... AND SOCIAL SERVICES PROGRAMS Direct Assistance Adult Care Assistance § 20.332 Who can receive Adult Care Assistance? An adult Indian is eligible to receive adult care assistance under this part if he/she...

  16. 25 CFR 20.332 - Who can receive Adult Care Assistance?

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 25 Indians 1 2013-04-01 2013-04-01 false Who can receive Adult Care Assistance? 20.332 Section 20... AND SOCIAL SERVICES PROGRAMS Direct Assistance Adult Care Assistance § 20.332 Who can receive Adult Care Assistance? An adult Indian is eligible to receive adult care assistance under this part if he/she...

  17. 25 CFR 20.332 - Who can receive Adult Care Assistance?

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 25 Indians 1 2012-04-01 2011-04-01 true Who can receive Adult Care Assistance? 20.332 Section 20... AND SOCIAL SERVICES PROGRAMS Direct Assistance Adult Care Assistance § 20.332 Who can receive Adult Care Assistance? An adult Indian is eligible to receive adult care assistance under this part if he/she...

  18. 25 CFR 20.332 - Who can receive Adult Care Assistance?

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 25 Indians 1 2011-04-01 2011-04-01 false Who can receive Adult Care Assistance? 20.332 Section 20... AND SOCIAL SERVICES PROGRAMS Direct Assistance Adult Care Assistance § 20.332 Who can receive Adult Care Assistance? An adult Indian is eligible to receive adult care assistance under this part if he/she...

  19. Quantum limited performance of optical receivers

    NASA Astrophysics Data System (ADS)

    Farrell, Thomas C.

    2018-05-01

    While the fundamental performance limit for traditional radio frequency (RF) communications is often set by background noise on the channel, the fundamental limit for optical communications is set by the quantum nature of light. Both types of systems are based on electro-magnetic waves, differing only in carrier frequency. It is, in fact, the frequency that determines which of these limits dominates. We explore this in the first part of this paper. This leads to a difference in methods of analysis of the two different types of systems. While equations predicting the probability of bit error for RF systems are usually based on the signal to background noise ratio, similar equations for optical systems are often based on the physics of the quantum limit and are simply a function of the detected signal energy received per bit. These equations are derived in the second part of this paper for several frequently used modulation schemes: On-off keying (OOK), pulse position modulation (PPM), and binary differential phase shift keying (DPSK). While these equations ignore the effects of background noise and non-quantum internal noise sources in the detector and receiver electronics, they provide a useful bound for obtainable performance of optical communication systems. For example, these equations may be used in initial link budgets to assess the feasibility of system architectures, even before specific receiver designs are considered.

  20. 50th Anniversary of the World's First Extraterrestrial Sample Receiving Laboratory: The Apollo Program's Lunar Receiving Laboratory

    NASA Technical Reports Server (NTRS)

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

    2017-01-01

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

  1. New Results on Unconditionally Secure Multi-receiver Manual Authentication

    NASA Astrophysics Data System (ADS)

    Wang, Shuhong; Safavi-Naini, Reihaneh

    Manual authentication is a recently proposed model of communication motivated by the settings where the only trusted infrastructure is a low bandwidth authenticated channel, possibly realized by the aid of a human, that connects the sender and the receiver who are otherwise connected through an insecure channel and do not have any shared key or public key infrastructure. A good example of such scenarios is pairing of devices in Bluetooth. Manual authentication systems are studied in computational and information theoretic security model and protocols with provable security have been proposed. In this paper we extend the results in information theoretic model in two directions. Firstly, we extend a single receiver scenario to multireceiver case where the sender wants to authenticate the same message to a group of receivers. We show new attacks (compared to single receiver case) that can launched in this model and demonstrate that the single receiver lower bound 2log(1/ɛ) + O(1) on the bandwidth of manual channel stays valid in the multireceiver scenario. We further propose a protocol that achieves this bound and provides security, in the sense that we define, if up to c receivers are corrupted. The second direction is the study of non-interactive protocols in unconditionally secure model. We prove that unlike computational security framework, without interaction a secure authentication protocol requires the bandwidth of the manual channel to be at least the same as the message size, hence non-trivial protocols do not exist.

  2. Second-law efficiency of solar-thermal cavity receivers

    NASA Technical Reports Server (NTRS)

    Moynihan, P. I.

    1983-01-01

    Properly quantified performance of a solar-thermal cavity receiver must not only account for the energy gains and losses as dictated by the First Law of thermodynamics, but it must also account for the quality of that energy. However, energy quality can only be determined from the Second Law. An equation for the Second Law efficiency of a cavity receiver is derived from the definition of available energy, which is a thermodynamic property that measures the maximum amount of work obtainable when a system is allowed to come into unrestrained equilibrium with the surrounding environment. The fundamental concepts of the entropy and availability of radiation were explored from which a workable relationship among the reflected cone half-angle, the insolation, and the concentrator geometric characteristics was developed as part of the derivation of the Second Law efficiency. First and Second Law efficiencies were compared for data collected from two receivers that were designed for different purposes. A Second Law approach to quantifying the performance of a solar-thermal cavity receiver lends greater insight into the total performance than does the conventional First Law method.

  3. Compact Efficient Lidar Receiver for Measuring Atmospheric Aerosols

    NASA Technical Reports Server (NTRS)

    Gili, Christopher; De Young, Russell

    2006-01-01

    A small, light weight, and efficient aerosol lidar receiver was constructed and tested. Weight and space savings were realized by using rigid optic tubes and mounting cubes to package the steering optics and detectors in a compact assembly. The receiver had a 1064nm channel using an APD detector. The 532nm channel was split (90/10) into an analog channel (90%) and a photon counting channel (10%). The efficiency of the 1064nm channel with optical filter was 44.0%. The efficiency of the analog 532nm channel was 61.4% with the optical filter, and the efficiency of the 532nm photon counting channel was 7.6% with the optical filter. The results of the atmospheric tests show that the detectors were able to consistently return accurate results. The lidar receiver was able to detect distinct cloud layers, and the lidar returns also agreed across the different detectors. The use of a light weight fiber-coupled telescope reduced weight and allowed great latitude in detector assembly positioning due to the flexibility enabled by the use of fiber optics. The receiver is now ready to be deployed for aircraft or ground based aerosol lidar measurements.

  4. High Flux Microchannel Receiver Development with Adap-tive Flow Control

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Drost, Kevin

    This project is focused on the demonstration of a microchannel-based solar receiver (MSR). The MSR concept consists of using a modular arrangement of arrayed microchannels to heat a working fluid in a concentrating solar receiver, allowing a much higher solar flux on the receiver and consequently a significant reduction in thermal losses, size, and cost.

  5. Review and future perspective of central receiver design and performance

    NASA Astrophysics Data System (ADS)

    Zhu, Guangdong; Libby, Cara

    2017-06-01

    Concentrating solar power (CSP) technology provides a commercial solar option to the utility-scale electricity market. CSP is unique in its ability to include low-cost thermal storage; thus, it can generate electricity when the sun is not available and dispatch electricity to meet varying load requirements. Within the suite of CSP technologies, the central receiver design represents the state-of-the-art technology, promising low cost, high performance, and dispatchable energy production. Current total capacity of central receiver plants worldwide is about 1.0 gigawatt (electric) with operating plants in Spain and the United States, as well as projects under construction in Asia, the Middle East, and North Africa. Central receiver technology has been under development since the 1950s, and a variety of central receiver designs have been explored. A distinguishing feature is the heat transfer medium. Central receiver designs exist that use dense fluids, gases, and solid particles in this role. Water/steam and molten salt receivers have been adopted in current commercial plants and are often coupled with a steam-Rankine power cycle with an operating temperature of less than 600°C. Many new central receiver concepts, such as the volumetric air, supercritical carbon dioxide (sCO2), solid particle, and liquid-metal receiver designs, are under active research and development (R&D). New designs target operating temperatures generally higher than 700°C-800°C—and even above 1000°C—so that higher-performance power cycles such as the sCO2-Brayton cycle or air-Brayton/steam-Rankine combined cycle can be used to promote greater overall system efficiency. Central receiver thermal storage provides dispatchability unavailable from variable-output renewables such as solar photovoltaic and wind power. Case study analysis of the California grid shows that there is a limit on the amount of non-dispatchable renewable generation that the grid can accommodate, beyond which

  6. Review and Future Perspective of Central Receiver Design and Performance

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zhu, Guangdong; Libby, Cara

    Concentrating solar power (CSP) technology provides a commercial solar option to the utility-scale electricity market. CSP is unique in its ability to include low-cost thermal storage; thus, it can generate electricity when the sun is not available and dispatch electricity to meet varying load requirements. Within the suite of CSP technologies, the central receiver design represents the state-of-the-art technology, promising low cost, high performance, and dispatchable energy production. Current total capacity of central receiver plants worldwide is about 1.0 gigawatt (electric) with operating plants in Spain and the United States, as well as projects under construction in Asia, the Middlemore » East, and North Africa. Central receiver technology has been under development since the 1950s, and a variety of central receiver designs have been explored. A distinguishing feature is the heat transfer medium. Central receiver designs exist that use dense fluids, gases, and solid particles in this role. Water/steam and molten salt receivers have been adopted in current commercial plants and are often coupled with a steam-Rankine power cycle with an operating temperature of less than 600 degrees C. Many new central receiver concepts, such as the volumetric air, supercritical carbon dioxide (sCO2), solid particle, and liquid-metal receiver designs, are under active research and development (R&D). New designs target operating temperatures generally higher than 700 degrees C-800 degrees C -- and even above 1000 degrees C -- so that higher-performance power cycles such as the sCO2-Brayton cycle or air-Brayton/steam-Rankine combined cycle can be used to promote greater overall system efficiency. Central receiver thermal storage provides dispatchability unavailable from variable-output renewables such as solar photovoltaic and wind power. Case study analysis of the California grid shows that there is a limit on the amount of non-dispatchable renewable generation that the grid

  7. Financial reserve. Hospitals leery of credit lines, factoring receivables.

    PubMed

    Edwards, D E; Hamilton, W C; Hauser, R

    1991-10-01

    Opening lines of credit and factoring (selling) accounts receivable are two ways to generate operating cash that non-healthcare industries have long used successfully. A recent survey of hospital officials across the nation, however, showed these techniques are used infrequently in health care. Among the 281 hospitals responding: Only 45 percent use lines of credit; Less than 5 percent pursue accounts receivable factoring; and Only 12 percent plan to begin factoring receivables in the future. As hospitals look for ways to offset depleted cash reserves, these percentages may increase.

  8. 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.

  9. Analysis of the WindSat Receiver Frequency Passbands

    DTIC Science & Technology

    2014-09-12

    water vapor ( PWV ) calculated for each atmospheric profile. The differences for the 18.7 and 23.8 GHz bands vary with PWV . Modeled Tb’s for receiver...precipitable water vapor ( PWV ). WindSat Receiver Frequency Passbands 11 22 24 26 28 30 32 34 36 38 40 REU Temperature (°C) 0 1 2 3 4 5 P er ce nt o f O cc

  10. Superconductive hot-electron-bolometer mixer receiver for 800-GHz operation

    NASA Astrophysics Data System (ADS)

    Kawamura, J.; Blundell, R.; Tong, C.-Y. E.; Papa, D. C.; Hunter, T. R.; Paine, S. N.; Patt, F.; Gol'Tsman, G.; Cherednichenko, S.; Voronov, B.; Gershenzon, E.

    2000-04-01

    In this paper, we describe a superconductive hot-electron-bolometer mixer receiver designed to operate in the partially transmissive 350-μm atmospheric window. The receiver employs an NbN thin-film microbridge as the mixer element, in which the main cooling mechanism of the hot electrons is through electron-phonon interaction. At a local-oscillator frequency of 808 GHz, the measured double-sideband receiver noise temperature is Trx=970 K, across a 1-GHz intermediate-frequency bandwidth centered at 1.8 GHz. We have measured the linearity of the receiver and the amount of local-oscillator power incident on the mixer for optimal operation, which is PLO ≈ 1 microwatt. This receiver was used in making observations as a facility instrument at the Heinrich Hertz Telescope, Mt. Graham, AZ, during the 1998-1999 winter observing season.

  11. Receiver psychology turns 20: is it time for a broader approach?

    PubMed Central

    Miller, Cory T.; Bee, Mark A.

    2013-01-01

    Twenty years ago, a new conceptual paradigm known as ‘receiver psychology’ was introduced to explain the evolution of animal communication systems. This paradigm advanced the idea that psychological processes in the receiver's nervous system influence a signal's detectability, discriminability and memorability, and thereby serve as powerful sources of selection shaping signal design. While advancing our understanding of signal diversity, more recent studies make clear that receiver psychology, as a paradigm, has been structured too narrowly and does not incorporate many of the perceptual and cognitive processes of signal reception that operate between sensory transduction and a receiver's response. Consequently, the past two decades of research on receiver psychology have emphasized considerations of signal evolution but failed to ask key questions about the mechanisms of signal reception and their evolution. The primary aim of this essay is to advocate for a broader receiver psychology paradigm that more explicitly includes a research focus on receivers' psychological landscapes. We review recent experimental studies of hearing and sound communication to illustrate how considerations of several general perceptual and cognitive processes will facilitate future research on animal signalling systems. We also emphasize how a rigorous comparative approach to receiver psychology is critical to explicating the full range of perceptual and cognitive processes involved in receiving and responding to signals. PMID:24013277

  12. 25 CFR 171.205 - How much water will I receive?

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 25 Indians 1 2012-04-01 2011-04-01 true How much water will I receive? 171.205 Section 171.205 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER IRRIGATION OPERATION AND MAINTENANCE Irrigation Service § 171.205 How much water will I receive? The amount of water you receive will be based on your request, your legal...

  13. 25 CFR 171.205 - How much water will I receive?

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 25 Indians 1 2011-04-01 2011-04-01 false How much water will I receive? 171.205 Section 171.205 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER IRRIGATION OPERATION AND MAINTENANCE Irrigation Service § 171.205 How much water will I receive? The amount of water you receive will be based on your request, your legal...

  14. 25 CFR 171.205 - How much water will I receive?

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false How much water will I receive? 171.205 Section 171.205 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER IRRIGATION OPERATION AND MAINTENANCE Irrigation Service § 171.205 How much water will I receive? The amount of water you receive will be based on your request, your legal...

  15. Evaluation of the variability of wind speed at different heights and its impact on the receiver efficiency of central receiver systems

    NASA Astrophysics Data System (ADS)

    Delgado, A.; Gertig, C.; Blesa, E.; Loza, A.; Hidalgo, C.; Ron, R.

    2016-05-01

    Typical plant configurations for Central Receiver Systems (CRS) are comprised of a large field of heliostats which concentrate solar irradiation onto the receiver, which is elevated hundreds of meters above the ground. Wind speed changes with altitude above ground, impacting on the receiver thermal efficiency due to variations of the convective heat losses. In addition, the physical properties of air vary at high altitudes to a significant degree, which should be considered in the thermal losses calculation. DNV GL has long-reaching experience in wind energy assessment with reliable methodologies to reduce the uncertainty of the determination of the wind regime. As a part of this study, DNV GL estimates the wind speed at high altitude for different sites using two methods, a detailed estimation applying the best practices used in the wind energy sector based on measurements from various wind sensors and a simplified estimation applying the power law (1, 2) using only one wind measurement and a representative value for the surface roughness. As a result of the study, a comparison of the wind speed estimation considering both methods is presented and the impact on the receiver performance for the evaluated case is estimated.

  16. Multistage estimation of received carrier signal parameters under very high dynamic conditions of the receiver

    NASA Technical Reports Server (NTRS)

    Kumar, Rajendra (Inventor)

    1991-01-01

    A multistage estimator is provided for the parameters of a received carrier signal possibly phase-modulated by unknown data and experiencing very high Doppler, Doppler rate, etc., as may arise, for example, in the case of Global Positioning Systems (GPS) where the signal parameters are directly related to the position, velocity and jerk of the GPS ground-based receiver. In a two-stage embodiment of the more general multistage scheme, the first stage, selected to be a modified least squares algorithm referred to as differential least squares (DLS), operates as a coarse estimator resulting in higher rms estimation errors but with a relatively small probability of the frequency estimation error exceeding one-half of the sampling frequency, provides relatively coarse estimates of the frequency and its derivatives. The second stage of the estimator, an extended Kalman filter (EKF), operates on the error signal available from the first stage refining the overall estimates of the phase along with a more refined estimate of frequency as well and in the process also reduces the number of cycle slips.

  17. Multistage estimation of received carrier signal parameters under very high dynamic conditions of the receiver

    NASA Technical Reports Server (NTRS)

    Kumar, Rajendra (Inventor)

    1990-01-01

    A multistage estimator is provided for the parameters of a received carrier signal possibly phase-modulated by unknown data and experiencing very high Doppler, Doppler rate, etc., as may arise, for example, in the case of Global Positioning Systems (GPS) where the signal parameters are directly related to the position, velocity and jerk of the GPS ground-based receiver. In a two-stage embodiment of the more general multistage scheme, the first stage, selected to be a modified least squares algorithm referred to as differential least squares (DLS), operates as a coarse estimator resulting in higher rms estimation errors but with a relatively small probability of the frequency estimation error exceeding one-half of the sampling frequency, provides relatively coarse estimates of the frequency and its derivatives. The second stage of the estimator, an extended Kalman filter (EKF), operates on the error signal available from the first stage refining the overall estimates of the phase along with a more refined estimate of frequency as well and in the process also reduces the number of cycle slips.

  18. Flight Performance Evaluation of Three GPS Receivers for Sounding Rocket Tracking

    NASA Technical Reports Server (NTRS)

    Bull, Barton; Diehl, James; Montenbruck, Oliver; Markgraf, Markus; Bauer, Frank (Technical Monitor)

    2001-01-01

    In preparation for the European Space Agency Maxus-4 mission, a sounding rocket test flight was carried out at Esrange,, near Kiruna, Sweden on February 19, 2001 to validate existing ground facilities and range safety installations. Due to the absence of a dedicated scientific payload, the flight offered the opportunity to test multiple GPS receivers and assess their performance for the tracking of sounding rockets. The receivers included an Ashtech G12 HDMA receiver, a BAE (Canadian Marconi) Allstar receiver and a Mitel Orion receiver. All of them provide CIA code tracking on the L1 frequency to determine the user position and make use of Doppler measurements to derive the instantaneous velocity. Among the receivers, the G12 has been optimized for use under highly dynamic conditions and has earlier been flown successfully on NASA sounding rockets [Bull, ION-GPS-2000]. The Allstar is representative of common single frequency receivers for terrestrial applications and received no particular modification, except for the disabling of the common altitude and velocity constraints that would otherwise inhibit its use for space application. The Orion receiver, finally, employs the same Mitel chipset as the Allstar, but has received various firmware modifications by DLR to safeguard it against signal losses and improve its tracking performance [Montenbruck et al., ION-GPS-2000]. While the two NASA receivers were driven by a common wrap-around antenna, the DLR experiment made use of a switchable antenna system comprising a helical antenna in the tip of the rocket and two blade antennas attached to the body of the vehicle. During the boost a peak acceleration of roughly 17g's was achieved which resulted in a velocity of about 1100 m/s at the end of the burn. At apogee, the rocket reached a maximum altitude of over 80 km. A detailed analysis of the attained flight data will be given in the paper together with a evaluation of different receiver designs and antenna concepts.

  19. Flight Performance Evaluation of Three GPS Receivers for Sounding Rocket Tracking

    NASA Technical Reports Server (NTRS)

    Bull, Barton; Diehl, James; Montenbruck, Oliver; Markgraf, Markus; Bauer, Frank (Technical Monitor)

    2002-01-01

    In preparation for the European Space Agency Maxus-4 mission, a sounding rocket test flight was carried out at Esrange, near Kiruna, Sweden on February 19, 2001 to validate existing ground facilities and range safety installations. Due to the absence of a dedicated scientific payload, the flight offered the opportunity to test multiple GPS receivers and assess their performance for the tracking of sounding rockets. The receivers included an Ashtech G12 HDMA receiver, a BAE (Canadian Marconi) Allstar receiver and a Mitel Orion receiver. All of them provide C/A code tracking on the L1 frequency to determine the user position and make use of Doppler measurements to derive the instantaneous velocity. Among the receivers, the G12 has been optimized for use under highly dynamic conditions and has earlier been flown successfully on NASA sounding rockets. The Allstar is representative of common single frequency receivers for terrestrial applications and received no particular modification, except for the disabling of the common altitude and velocity constraints that would otherwise inhibit its use for space application. The Orion receiver, finally, employs the same Mitel chipset as the Allstar, but has received various firmware modifications by DLR to safeguard it against signal losses and improve its tracking performance. While the two NASA receivers were driven by a common wrap-around antenna, the DLR experiment made use of a switchable antenna system comprising a helical antenna in the tip of the rocket and two blade antennas attached to the body of the vehicle. During the boost a peak acceleration of roughly l7g's was achieved which resulted in a velocity of about 1100 m/s at the end of the burn. At apogee, the rocket reached an altitude of over 80 km. A detailed analysis of the attained flight data is given together with a evaluation of different receiver designs and antenna concepts.

  20. 47 CFR 27.58 - Interference to BRS/EBS receivers.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 2 2011-10-01 2011-10-01 false Interference to BRS/EBS receivers. 27.58 Section 27.58 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES Technical Standards § 27.58 Interference to BRS/EBS receivers. (a...

  1. Survey of State-of-the-Art LORAN-C Receivers

    DOT National Transportation Integrated Search

    1984-01-01

    This report is a summary of the state-of-the-art in LORAN-C receiver design (April 1984). The data sources were manufacturers, designers, and trade literature. Every effort was made to accurately depict the status of receiver design activity in the m...

  2. Monolithic optoelectronic integrated broadband optical receiver with graphene photodetectors

    NASA Astrophysics Data System (ADS)

    Cheng, Chuantong; Huang, Beiju; Mao, Xurui; Zhang, Zanyun; Zhang, Zan; Geng, Zhaoxin; Xue, Ping; Chen, Hongda

    2017-07-01

    Optical receivers with potentially high operation bandwidth and low cost have received considerable interest due to rapidly growing data traffic and potential Tb/s optical interconnect requirements. Experimental realization of 65 GHz optical signal detection and 262 GHz intrinsic operation speed reveals the significance role of graphene photodetectors (PDs) in optical interconnect domains. In this work, a novel complementary metal oxide semiconductor post-backend process has been developed for integrating graphene PDs onto silicon integrated circuit chips. A prototype monolithic optoelectronic integrated optical receiver has been successfully demonstrated for the first time. Moreover, this is a firstly reported broadband optical receiver benefiting from natural broadband light absorption features of graphene material. This work is a perfect exhibition of the concept of monolithic optoelectronic integration and will pave way to monolithically integrated graphene optoelectronic devices with silicon ICs for three-dimensional optoelectronic integrated circuit chips.

  3. AEETES - A solar reflux receiver thermal performance numerical model

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hogan, R.E. Jr.

    1994-02-01

    Reflux solar receivers for dish-Stirling electric power generation systems are currently being investigated by several companies and laboratories. In support of these efforts, the AEETES thermal performance numerical model has been developed to predict thermal performance of pool-boiler and heat-pipe reflux receivers. The formulation of the AEETES numerical model, which is applicable to axisymmetric geometries with asymmetric incident fluxes, is presented in detail. Thermal efficiency predictions agree to within 4.1% with test data from on-sun tests of a pool-boiler reflux receiver. Predicted absorber and sidewall temperatures agree with thermocouple data to within 3.3 and 7.3%, respectively. The importance of accountingmore » for the asymmetric incident fluxes is demonstrated in comparisons with predictions using azimuthally averaged variables. The predicted receiver heat losses are characterized in terms of convective, solar radiative, and infrared radiative, and conductive heat transfer mechanisms.« less

  4. Four-channel magnetic resonance imaging receiver using frequency domain multiplexing.

    PubMed

    He, Wang; Qin, Xu; Jiejing, Ren; Gengying, Li

    2007-01-01

    An alternative technique that uses frequency domain multiplexing to acquire phased array magnetic resonance images is discussed in detail. The proposed method has advantages over traditional independent receiver chains in that it utilizes an analog-to-digital converter and a single-chip multicarrier receiver with high performance to reduce the size and cost of the phased array receiver system. A practical four-channel digital receiver using frequency domain multiplexing was implemented and verified on a home-built 0.3 T magnetic resonance imaging system. The experimental results confirmed that the cross talk between each channel was below -60 dB, the phase fluctuations were about 1 degrees , and there was no obvious signal-to-noise ratio degradation. It is demonstrated that the frequency domain multiplexing is a valuable and economical technique, particularly for array coil systems where the multichannel receiver is indispensable and dynamic range is not a critical problem.

  5. Breakthrough Clostridium difficile Infection in Cirrhotic Patients Receiving Rifaximin.

    PubMed

    Reigadas, Elena; Alcalá, Luis; Gómez, Javier; Marín, Mercedes; Martin, Adoración; Onori, Raffaella; Muñoz, Patricia; Bouza, Emilio

    2018-03-19

    Patients with cirrhosis are at high risk of Clostridium difficile infection (CDI). Rifaximin is commonly used in cirrhotic patients as prophylaxis for hepatic encephalopathy (HE). Several studies have demonstrated the efficacy of rifaximin in the treatment of CDI; however, resistance to rifaximin has also been reported. Few studies have assessed the risk of developing CDI in cirrhotic patients receiving rifaximin. Our objective was to assess the incidence and characteristics of CDI in patients with cirrhosis, especially in those who received rifaximin. We assessed the incidence and clinical characteristics of CDI in cirrhotic patients over a 6-year period in our hospital. Medical charts were retrospectively reviewed. Ribotyping and antimicrobial susceptibility testing of all strains against rifaximin were performed. A total of 388 cirrhotic patients were included, of whom 127 patients had at least 1 episode of diarrhea in which a sample was sent to the laboratory. CDI was detected in 46 patients. Fourteen patients (30.4%) were receiving rifaximin as prophylaxis for HE. The main ribotypes detected were 001 (30.4%), followed by 014 (19.6%). Resistance to rifaximin was 34.1% overall, and 84.6% in patients who had received rifaximin. Multivariate analysis showed that rifamycin therapy and ribotype 001 were significant risk factors for having a rifaximin-resistant C. difficile strain. A high percentage of CDI cases were detected in cirrhotic patients receiving rifaximin, mostly owing to selection of rifaximin-resistant C. difficile strains. Clinicians should be aware of the risk of CDI in cirrhotic patients, even in those receiving rifaximin.

  6. Moving receive beam method and apparatus for synthetic aperture radar

    DOEpatents

    Kare, Jordin T.

    2001-01-01

    A method and apparatus for improving the performance of Synthetic Aperture Radar (SAR) systems by reducing the effect of "edge losses" associated with nonuniform receiver antenna gain. By moving the receiver antenna pattern in synchrony with the apparent motion of the transmitted pulse along the ground, the maximum available receiver antenna gain can be used at all times. Also, the receiver antenna gain for range-ambiguous return signals may be reduced, in some cases, by a large factor. The beam motion can be implemented by real-time adjustment of phase shifters in an electronically-steered phased-array antenna or by electronic switching of feed horns in a reflector antenna system.

  7. 48 CFR 246.370 - Material inspection and receiving report.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... deliverable is a scientific or technical report; (5) Research and development contracts not requiring the... receiving report. 246.370 Section 246.370 Federal Acquisition Regulations System DEFENSE ACQUISITION... Material inspection and receiving report. (a) Use the clause at 252.246-7000, Material Inspection and...

  8. 48 CFR 246.370 - Material inspection and receiving report.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... deliverable is a scientific or technical report; (5) Research and development contracts not requiring the... receiving report. 246.370 Section 246.370 Federal Acquisition Regulations System DEFENSE ACQUISITION... Material inspection and receiving report. (a) Use the clause at 252.246-7000, Material Inspection and...

  9. A Brayton cycle solar dynamic heat receiver for space

    NASA Technical Reports Server (NTRS)

    Sedgwick, L. M.; Nordwall, H. L.; Kaufmann, K. J.; Johnson, S. D.

    1989-01-01

    The detailed design of a heat receiver developed to meet the requirements of the Space Station Freedom, which will be assembled and operated in low earth orbit beginning in the mid-1990's, is described. The heat receiver supplies thermal energy to a nominal 25-kW closed-Brayton-cycle power conversion unit. The receiver employs an integral thermal energy storage system utilizing the latent heat of a eutectic-salt phase-change mixture to store energy for eclipse operation. The salt is contained within a felt metal matrix which enhances heat transfer and controls the salt void distribution during solidification.

  10. ALMA Band 5 receiver cartridge. Design, performance, and commissioning

    NASA Astrophysics Data System (ADS)

    Belitsky, V.; Bylund, M.; Desmaris, V.; Ermakov, A.; Ferm, S.-E.; Fredrixon, M.; Krause, S.; Lapkin, I.; Meledin, D.; Pavolotsky, A.; Rashid, H.; Shafiee, S.; Strandberg, M.; Sundin, E.; Aghdam, P. Yadranjee; Hesper, R.; Barkhof, J.; Bekema, M. E.; Adema, J.; Haan, R. de; Koops, A.; Boland, W.; Yagoubov, P.; Marconi, G.; Siringo, G.; Humphreys, E.; Tan, G. H.; Laing, R.; Testi, L.; Mroczkowski, T.; Wild, W.; Saini, K. S.; Bryerton, E.

    2018-04-01

    We describe the design, performance, and commissioning results for the new ALMA Band 5 receiver channel, 163-211 GHz, which is in the final stage of full deployment and expected to be available for observations in 2018. This manuscript provides the description of the new ALMA Band 5 receiver cartridge and serves as a reference for observers using the ALMA Band 5 receiver for observations. At the time of writing this paper, the ALMA Band 5 Production Consortium consisting of NOVA Instrumentation group, based in Groningen, NL, and GARD in Sweden have produced and delivered to ALMA Observatory over 60 receiver cartridges. All 60 cartridges fulfil the new more stringent specifications for Band 5 and demonstrate excellent noise temperatures, typically below 45 K single sideband (SSB) at 4 K detector physical temperature and below 35 K SSB at 3.5 K (typical for operation at the ALMA Frontend), providing the average sideband rejection better than 15 dB, and the integrated cross-polarization level better than -25 dB. The 70 warm cartridge assemblies, hosting Band 5 local oscillator and DC bias electronics, have been produced and delivered to ALMA by NRAO. The commissioning results confirm the excellent performance of the receivers.

  11. Network of Internet-Controlled HF Receivers for Ionospheric Researches

    NASA Astrophysics Data System (ADS)

    Koloskov, A. V.; Yampolski, Y. M.; Zalizovski, A. V.; Galushko, V. G.; Kascheev, A. S.; La Hoz, C.; Brekke, A.; Beley, V. S.; Rietveld, M. T.

    2014-12-01

    A network of HF receivers intended for multi-position monitoring of the ionosphere is described. At present, it includes nine observation sites located at high, middle and low latitudes in both hemispheres of the Earth. The basic element of the network is a small- size receiving and measuring units designed at the Institute of Radio Astronomy (IRA) of the National Academy of Sciences of Ukraine (NASU) on the basis of a personal computer equipped with commercial digital receiving modules. Software packages developed by the authors make it possible to remotely control the facilities via the Internet network. The received emissions are HF signals from special transmitters and broadcast radio stations. These are processed using Doppler and pulse selection algorithms. In the Internet-controlled mode, the observation results are transferred to the main server in real time to be automatically processed and visualized at the website of the IRA NASU’s Department of Radiophysics of Geospace. Several examples of using the observation results obtained with the HF receiver network for diagnostics of dynamic processes in the near-Earth plasma are presented. The advantages of the multiposition mode of observations are discussed. The possibility of upgrading the HF facilities to provide measuring angles of arrival of signals is considered.

  12. 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.

  13. ACHP | ACHP Receives Section 213 Report on Presidio of San Francisco

    Science.gov Websites

    Search skip specific nav links Home arrow News arrow ACHP Receives Section 213 Report on Presidio of San Francisco ACHP Receives Section 213 Report on Presidio of San Francisco The ACHP received its requested

  14. Design of coherent receiver optical front end for unamplified applications.

    PubMed

    Zhang, Bo; Malouin, Christian; Schmidt, Theodore J

    2012-01-30

    Advanced modulation schemes together with coherent detection and digital signal processing has enabled the next generation high-bandwidth optical communication systems. One of the key advantages of coherent detection is its superior receiver sensitivity compared to direct detection receivers due to the gain provided by the local oscillator (LO). In unamplified applications, such as metro and edge networks, the ultimate receiver sensitivity is dictated by the amount of shot noise, thermal noise, and the residual beating of the local oscillator with relative intensity noise (LO-RIN). We show that the best sensitivity is achieved when the thermal noise is balanced with the residual LO-RIN beat noise, which results in an optimum LO power. The impact of thermal noise from the transimpedance amplifier (TIA), the RIN from the LO, and the common mode rejection ratio (CMRR) from a balanced photodiode are individually analyzed via analytical models and compared to numerical simulations. The analytical model results match well with those of the numerical simulations, providing a simplified method to quantify the impact of receiver design tradeoffs. For a practical 100 Gb/s integrated coherent receiver with 7% FEC overhead, we show that an optimum receiver sensitivity of -33 dBm can be achieved at GFEC cliff of 8.55E-5 if the LO power is optimized at 11 dBm. We also discuss a potential method to monitor the imperfections of a balanced and integrated coherent receiver.

  15. Fiber-based free-space optical coherent receiver with vibration compensation mechanism.

    PubMed

    Zhang, Ruochi; Wang, Jianmin; Zhao, Guang; Lv, Junyi

    2013-07-29

    We propose a novel fiber-based free-space optical (FSO) coherent receiver for inter-satellite communication. The receiver takes advantage of established fiber-optic components and utilizes the fine-pointing subsystem installed in FSO terminals to minimize the influence of satellite platform vibrations. The received beam is coupled to a single-mode fiber, and the coupling efficiency of the system is investigated both analytically and experimentally. A receiving sensitivity of -38 dBm is obtained at the forward error correction limit with a transmission rate of 22.4 Gbit/s. The proposed receiver is shown to be a promising component for inter-satellite optical communication.

  16. 20 CFR 663.220 - Who may receive intensive services?

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...) ADULT AND DISLOCATED WORKER ACTIVITIES UNDER TITLE I OF THE WORKFORCE INVESTMENT ACT Intensive Services § 663.220 Who may receive intensive services? There are two categories of adults and dislocated workers who may receive intensive services: (a) Adults and dislocated workers who are unemployed, have...

  17. 7 CFR 400.209 - Electronic transmission and receiving system.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 6 2013-01-01 2013-01-01 false Electronic transmission and receiving system. 400.209... Contract-Standards for Approval § 400.209 Electronic transmission and receiving system. Any Contractor...; (b) Maintain an electronic system which must be tested and approved by the Corporation; (c) Maintain...

  18. 7 CFR 400.209 - Electronic transmission and receiving system.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 6 2011-01-01 2011-01-01 false Electronic transmission and receiving system. 400.209... Contract-Standards for Approval § 400.209 Electronic transmission and receiving system. Any Contractor...; (b) Maintain an electronic system which must be tested and approved by the Corporation; (c) Maintain...

  19. 7 CFR 400.209 - Electronic transmission and receiving system.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 6 2010-01-01 2010-01-01 false Electronic transmission and receiving system. 400.209... Contract-Standards for Approval § 400.209 Electronic transmission and receiving system. Any Contractor...; (b) Maintain an electronic system which must be tested and approved by the Corporation; (c) Maintain...

  20. 7 CFR 400.209 - Electronic transmission and receiving system.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 6 2012-01-01 2012-01-01 false Electronic transmission and receiving system. 400.209... Contract-Standards for Approval § 400.209 Electronic transmission and receiving system. Any Contractor...; (b) Maintain an electronic system which must be tested and approved by the Corporation; (c) Maintain...