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Sample records for aids-related immunoblastic large

  1. Gene Therapy After Frontline Chemotherapy in Treating Patients With AIDS-Related Non-Hodgkin Lymphoma

    ClinicalTrials.gov

    2016-03-14

    AIDS-related Diffuse Large Cell Lymphoma; AIDS-related Diffuse Mixed Cell Lymphoma; AIDS-related Diffuse Small Cleaved Cell Lymphoma; AIDS-related Immunoblastic Large Cell Lymphoma; AIDS-related Lymphoblastic Lymphoma; AIDS-related Small Noncleaved Cell Lymphoma; HIV Infection

  2. Loss of HLA-DR expression and immunoblastic morphology predict adverse outcome in diffuse large B-cell lymphoma – analyses of cases from two prospective randomized clinical trials

    PubMed Central

    Bernd, Heinz-Wolfram; Ziepert, Marita; Thorns, Christoph; Klapper, Wolfram; Wacker, Hans-Heinrich; Hummel, Michael; Stein, Harald; Hansmann, Martin-Leo; Ott, German; Rosenwald, Andreas; Müller-Hermelink, Hans-Konrad; Barth, Thomas F. E.; Möller, Peter; Cogliatti, Sergio B.; Pfreundschuh, Michael; Schmitz, Norbert; Trümper, Lorenz; Höller, Silvia; Löffler, Markus; Feller, Alfred C.

    2009-01-01

    Background Research on prognostically relevant immunohistochemical markers in diffuse large B-cell lymphomas has mostly been performed on retrospectively collected clinical data. This is also true for immunohistochemical classifiers that are thought to reflect the cell-of-origin subclassification of gene expression studies. In order to obtain deeper insight into the heterogeneous prognosis of diffuse large B-cell lymphomas and to validate a previously published immunohistochemical classifier, we analyzed data from a large set of cases from prospective clinical trials with long-term follow-up. Design and Methods We performed morphological and extensive immunohistochemical analyses in 414 cases of diffuse large B-cell lymphoma from two prospective randomized clinical trials (NHL-B1/B2, Germany). Classification into germinal center and non-germinal center subtypes of B-cell lymphoma was based on the expression pattern of CD10, BCL6, and IRF4. Multivariate analyses were performed adjusting for the factors in the International Prognostic Index. Results Analyzing 20 different epitopes on tissue microarrays, expression of HLA-DR, presence of CD23+ follicular dendritic cell meshworks, and monotypic light chain expression emerged as International Prognostic Index-independent markers of superior overall survival. Immunoblastic morphology was found to be related to poor event-free survival. The non-germinal center subtype, according to the three-epitope classifier (CD10, BCL6, and IRF4) did not have prognostic relevance when adjusted for International Prognostic Index factors (relative risk=1.2, p=0.328 for overall survival; and relative risk=1.1, p=0.644 for event-free survival). Conclusions The previously reported International Prognostic Index-independent prognostic value of stratification into germinal center/non-germinal center B-cell lymphoma using the expression pattern of CD10, BCL6, and IRF4 was not reproducible in our series. However, other markers and the

  3. Treatment outcomes in AIDS-related diffuse large B-cell lymphoma in the setting roll-out of combination antiretroviral therapy in South Africa

    PubMed Central

    de Witt, Pieter; Maartens, Deborah J; Uldrick, Thomas S; Sissolak, Gerhard

    2013-01-01

    Background Long term survival for patients with AIDS-related diffuse large B-cell lymphoma (DLBCL) is feasible in settings with available combination antiretroviral therapy (cART). However, given limited oncology resources, outcomes for AIDS-associated DLBCL in South Africa are unknown. Methods We performed a retrospective analysis of survival in patients with newly diagnosed AIDS-related diffuse large B-cell lymphoma (DLBCL) treated at a tertiary teaching hospital in Cape Town, South Africa with CHOP or CHOP-like chemotherapy (January 2004 until Dec 2010). HIV and lymphoma related prognostic factors were evaluated. Results 36 patients evaluated; median age 37.3 years, 52.8% men, and 61.1% black South Africans. Median CD4 count 184 cells/μl (in 27.8% this was < 100 cells/μl), 80% high-risk according to the age-adjusted International Prognostic Index. Concurrent Mycobacterium tuberculosis in 25%. Two-year overall survival (OS) was 40.5% (median OS 10.5 months, 95%CI 6.5 – 31.8). ECOG performance status of 2 or more (25.4% versus 50.0%, p = 0.01) and poor response to cART (18.0% versus 53.9%, p = 0.03) predicted inferior 2-year OS. No difference in 2-year OS was demonstrated in patients co-infected with Mycobacterium tuberculosis (p = 0.87). Conclusions Two-year OS for patients with AIDS-related DLBCL treated with CHOP like regimens and cART is comparable to that seen in the US and Europe. Important factors effecting OS in AIDS-related DLBCL in South Africa include performance status at presentation and response to cART. Patients with co-morbid Mycobacterium tuberculosis or hepatitis B seropositivity appear to tolerate CHOP in our setting. Additional improvements in outcomes are likely possible. PMID:23797692

  4. Hodgkin's disease terminating in a T-cell immunoblastic leukemia.

    PubMed

    Dick, F R; Maca, R D; Hankenson, R

    1978-09-01

    A patient who developed an immunoblastic leukemia of T-cell type two and one half years after initial diagnosis of mixed cellularity Hodgkin's disease, stage IIIB, is described. The patient's course was characterized by an initial 15-months remission following radiation therapy. A relapse of Hodgkin's disease was treated with intensive chemotherapy. Thirteen months later the patient entered a rapid terminal course with multiple organ infiltrates and a leukemic peripheral blood. The leukemic phase was characterized by a 55,000 WGC with 48% immunoblasts, greater than 90% of which marked as T-cells. Although acute myelogenous leukemia, acute lymphocytic leukemia, lymphosarcoma cell leukemia and other tumors have been described in Hodgkin's disease after intensive therapy, this is the first report of the unusual association of a T-cell immunoblastic leukemia with Hodgkin's disease. PMID:308839

  5. Immunophenotypic Analysis of AIDS-Related Diffuse Large B-Cell Lymphoma and Clinical Implications in Patients From AIDS Malignancies Consortium Clinical Trials 010 and 034

    PubMed Central

    Chadburn, Amy; Chiu, April; Lee, Jeannette Y.; Chen, Xia; Hyjek, Elizabeth; Banham, Alison H.; Noy, Ariela; Kaplan, Lawrence D.; Sparano, Joseph A.; Bhatia, Kishor; Cesarman, Ethel

    2009-01-01

    Purpose Diffuse large B-cell lymphoma (DLBCL) represents a clinically heterogeneous disease. Models based on immunohistochemistry predict clinical outcome. These include subdivision into germinal center (GC) versus non-GC subtypes; proliferation index (measured by expression of Ki-67), and expression of BCL-2, FOXP1, or B-lymphocyte-induced maturation protein (Blimp-1)/PRDM1. We sought to determine whether immunohistochemical analyses of biopsies from patients with DLBCL having HIV infection are similarly relevant for prognosis. Patients and Methods We examined 81 DLBCLs from patients with AIDS in AMC010 (cyclophosphamide, doxorubicin, vincristine, and prednisone [CHOP] v CHOP-rituximab) and AMC034 (etoposide, doxorubicin, vincristine, prednisone, and dose-adjusted cyclophosphamide plus rituximab concurrent v sequential) clinical trials and compared the immunophenotype with survival data, Epstein-Barr virus (EBV) positivity, and CD4 counts. Results The GC and non-GC subtypes of DLBCL did not differ significantly with respect to overall survival or CD4 count at cancer presentation. EBV could be found in both subtypes of DLBCL, although less frequently in the GC subtype, and did not affect survival. Expression of FOXP1, Blimp-1/PRDM1, or BCL-2 was not correlated with the outcome in patients with AIDS-related DLBCL. Conclusion These data indicate that with current treatment strategies for lymphoma and control of HIV infection, commonly used immunohistochemical markers may not be clinically relevant in HIV-infected patients with DLBCL. The only predictive immunohistochemical marker was found to be Ki-67, where a higher proliferation index was associated with better survival, suggesting a better response to therapy in patients whose tumors had higher proliferation rates. PMID:19752343

  6. Chronic myeloid leukemia with monoclonal gammopathy terminating in myeloid crisis and immunoblastic lymphoma.

    PubMed

    Larocca, L M; Zollino, M; Carbone, A; Eboli, M L; Mango, G; Leone, G

    1989-04-30

    A patient, with chronic myeloid leukemia and IgA monoclonal gammopathy, who contemporaneously developed myeloid blast crisis and immunoblastic lymphoma is reported. Cytogenetic studies showed complex chromosome abnormalities concerning chromosomes 8, 14 and 22, other than the Ph chromosome. A possible relationship between the emergence of immunoblasts from slow proliferating lymphoplasmacytoid cells, myeloid blasts crisis and chromosomal changes is discussed. PMID:2741214

  7. Immunoblastic transformation of a Sezary syndrome in a black Caribbean patient without evidence of HTLV-I.

    PubMed

    Matutes, E; Schulz, T; Dyer, M; Ellis, J; Hedges, M; Catovsky, D

    1995-08-01

    We describe an unusual case of Sezary syndrome which transformed into a large T-cell non Hodgkin's lymphoma (immunoblastic) in a black man of Caribbean descent with negative HTLV-I serology and no evidence of HTLV-I infection by DNA analysis using sensitive techniques. The disease presented as a small-cell Sezary syndrome and transformed in an inguinal lymph node one year from diagnosis. Immunological markers in the small and large cells showed a mature T-cell phenotype CD4+, CD8- with expression of T-cell activation markers and a high proliferative rate. Ultrastructural analysis confirmed small Sezary cells with serpentine nucleus in the peripheral blood and immunoblasts in the lymph node. Cytogenetics demonstrated complex clonal chromosome abnormalities with involvement of 7q35, the locus for the beta chain of the T-cell receptor (TCR). Southern-blot analysis showed the same rearrangement of the TCR beta, gamma, delta chain genes in lymph node and peripheral blood cells. Antibodies to HTLV-I were not detected in the serum by ELISA and particle agglutination (PA) nor HTLV-I specific sequences were demonstrated by nested polymerase chain reaction with primers to the envelope proteins, LTR and tax/rex of HTLV-I in both tissues, blood and lymph node. The disease had an aggressive course and was refractory to therapy; the patient died of progressive disease 28 months from presentation. Two unusual features characterised this patient's illness: immunoblastic transformation of a Sezary syndrome in a patient of Afro-Caribbean origin without evidence of HTLV-I DNA sequences and negative HTLV-I serology and the atypical lymph node histology resembling ATLL. PMID:8528063

  8. General Information about AIDS-Related Lymphoma

    MedlinePlus

    ... AIDS-Related Lymphoma Treatment (PDQ®)–Patient Version General Information About AIDS-Related Lymphoma Go to Health Professional ... the PDQ Adult Treatment Editorial Board . Clinical Trial Information A clinical trial is a study to answer ...

  9. Intravenous Chemotherapy or Oral Chemotherapy in Treating Patients With Previously Untreated Stage III-IV HIV-Associated Non-Hodgkin Lymphoma

    ClinicalTrials.gov

    2016-06-09

    AIDS-related Diffuse Large Cell Lymphoma; AIDS-related Diffuse Mixed Cell Lymphoma; AIDS-related Diffuse Small Cleaved Cell Lymphoma; AIDS-related Immunoblastic Large Cell Lymphoma; AIDS-related Lymphoblastic Lymphoma; AIDS-related Peripheral/Systemic Lymphoma; AIDS-related Small Noncleaved Cell Lymphoma; Stage III AIDS-related Lymphoma; Stage IV AIDS-related Lymphoma

  10. Aids-Related Cancers in Africa

    NASA Astrophysics Data System (ADS)

    Mbulaiteye, Sam M.

    2014-07-01

    Thank you Professor Zichichi for inviting me to give a talk about AIDS-related cancers in Africa. Let me begin by congratulating the team that organized the 46th Session of the Erice International Seminar Series, whose theme is THE ROLE OF SCIENCE IN THE THIRD MILLENIUM. I also congratulate the scientists from 38 countries who are attending these seminars. They are perpetuating the principle of SCIENCE WITHOUT SECRETS in the true spirit espoused by Archimedes, Galileo, and Fermi. It is a wonderful honor for me to be here to shed some light on the health impacts of the HIV epidemic in the area of cancer...

  11. Thymostimulin treatment in AIDS-related complex.

    PubMed

    Palmisano, L; Chisesi, T; Galli, M; Gritti, F M; Ielasi, G; Lazzarin, A; Mezzaroma, I; Moroni, M; Raise, E; Vaglia, A

    1988-06-01

    Thirty-four patients with AIDS-related complex (ARC) were treated for 6 months with thymostimulin, a thymic hormone. Clinical and immunological findings after a 1-year follow-up were compared with those in 24 age- and sex-matched controls receiving no immunotherapy. Statistical evaluation after 6 and 12 months showed significant differences in the two groups. The thymostimulin-treated group had higher leukocyte and lymphocyte counts, more positivity in intradermal tests with multiple recall antigens, and less lymphadenopathy and weight loss. The number of OKT3+ and OKT4+ lymphocytes decreased significantly in the control group, but did not change in the thymostimulin-treated patients. Finally, after 18 months of follow-up, no progression to AIDS was seen among the treated subjects, whereas 3 of the controls developed the disease. We conclude that thymostimulin, alone or in combination with antiviral drugs, may be helpful in the management of ARC patients. PMID:3259480

  12. Pancreatic abnormalities and AIDS related sclerosing cholangitis.

    PubMed Central

    Teare, J P; Daly, C A; Rodgers, C; Padley, S P; Coker, R J; Main, J; Harris, J R; Scullion, D; Bray, G P; Summerfield, J A

    1997-01-01

    OBJECTIVES: Biliary tract abnormalities are well recognised in AIDS, most frequently related to opportunistic infection with Cryptosporidium, Microsporidium, and cytomegalovirus. We noted a high frequency of pancreatic abnormalities associated with biliary tract disease. To define these further we reviewed the clinical and radiological features in these patients. METHODS: Notes and radiographs were available from two centres for 83 HIV positive patients who had undergone endoscopic retrograde cholangiopancreatography for the investigation of cholestatic liver function tests or abdominal pain. RESULTS: 56 patients had AIDS related sclerosing cholangitis (ARSC); 86% of these patients had epigastric or right upper quadrant pain and 52% had hepatomegaly. Of the patients with ARSC, 10 had papillary stenosis alone, 11 had intra- and extrahepatic sclerosing cholangitis alone, and 35 had a combination of the two. Ampullary biopsies performed in 24 patients confirmed an opportunistic infection in 16. In 15 patients, intraluminal polyps were noted on the cholangiogram. Pancreatograms were available in 34 of the 45 patients with papillary stenosis, in which 29 (81%) had associated pancreatic duct dilatation, often with associated features of chronic pancreatitis. In the remaining 27 patients, final diagnoses included drug induced liver disease, acalculous cholecystitis, gall bladder empyema, chronic B virus hepatitis, and alcoholic liver disease. CONCLUSION: Pancreatic abnormalities are commonly seen with ARSC and may be responsible for some of the pain not relieved by biliary sphincterotomy. The most frequent radiographic biliary abnormality is papillary stenosis combined with ductal sclerosis. Images PMID:9389948

  13. AIDS-related lymphoma. Histopathology, immunophenotype, and association with Epstein-Barr virus as demonstrated by in situ nucleic acid hybridization.

    PubMed Central

    Hamilton-Dutoit, S. J.; Pallesen, G.; Franzmann, M. B.; Karkov, J.; Black, F.; Skinhøj, P.; Pedersen, C.

    1991-01-01

    To investigate the range of pathology shown by acquired immune deficiency syndrome (AIDS)-related lymphomas arising in an epidemiologically well-defined group of patients, all cases of lymphoma recognized in Danish human immunodeficiency virus (HIV)-infected individuals up to the end of 1988 were studied. Twenty-seven cases (26 high-grade non-Hodgkin's lymphoma [NHL], 1 Hodgkin's disease) were found, to give a cumulative incidence rate of 8% among Danish AIDS patients. Morphologically most NHL patients were classified into two groups: 1) high-grade tumors with a predominant population of immunoblasts, either monomorphic or more often polymorphic with plasmacytic differentiation; 2) Burkitt-type. Of 26 NHLs, 22 had a B-cell paraffin-section immunophenotype and 4 were non-B, non-T. Epstein-Barr virus (EBV) DNA was demonstrated in tumor cells of 12 of 24 cases (50%) using in situ nucleic acid hybridization with a 35S-labeled probe in paraffin sections. Epstein-Barr virus DNA was found in 65% of group 1 and 20% of group 2 tumors. This study suggests the existence of two main groups of AIDS-related lymphoma with different pathogeneses. First there are immunoblast-rich lesions, which usually are associated with EBV and morphologically resemble lymphomas described in immunosuppressed organ-transplantation patients. Second there are Burkitt-type tumors in which EBV sequences are less common and that may be pathogenetically analogous to sporadic Burkitt's lymphoma. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 PMID:1846263

  14. AIDS-related apprehensions among nursing students of Delhi.

    PubMed

    Kumar, A; Lal, P; Ingle, G K; Gulati, N

    1999-12-01

    Students from a nursing school of Delhi were surveyed anonymously using a self-administered questionnaire to explore various AIDS-related apprehensions and their possible reasons. The observations revealed that, majority of the students and their families/friends feared that these students were at risk of contracting HIV infection while providing routine patient care. A large number of students also opined that they would feel uncomfortable while talking, hugging, shaking hands, and sharing a room with an HIV positive person. The main reasons for their apprehensions were unsatisfactory anti-AIDS campaigning by the government, non-availability of sufficient protective measures in the health care settings, inadequate professional education related to prevention of HIV infection, and increase in HIV transmission following false sense of security due to excessive condom promotion. Findings of the study imply imparting factual knowledge addressing the concerns and removing misconceptions which influence attitudes and willingness of the nursing students to provide care to the HIV positives/AIDS patients, facts regarding efficacy of various preventive measures, and provision of counselling services in the event of exposure. PMID:10937297

  15. The tumor virus landscape of AIDS-related lymphomas.

    PubMed

    Arvey, Aaron; Ojesina, Akinyemi I; Pedamallu, Chandra Sekhar; Ballon, Gianna; Jung, Joonil; Duke, Fujiko; Leoncini, Lorenzo; De Falco, Giulia; Bressman, Eric; Tam, Wayne; Chadburn, Amy; Meyerson, Matthew; Cesarman, Ethel

    2015-05-14

    Immunodeficiency dramatically increases susceptibility to cancer as a result of reduced immune surveillance and enhanced opportunities for virus-mediated oncogenesis. Although AIDS-related lymphomas (ARLs) are frequently associated with known oncogenic viruses, many cases contain no known transforming virus. To discover novel transforming viruses, we profiled a set of ARL samples using whole transcriptome sequencing. We determined that Epstein-Barr virus (EBV) was the only virus detected in the tumor samples of this cohort, suggesting that if unidentified pathogens exist in this disease, they are present in <10% of cases or undetectable by our methods. To evaluate the role of EBV in ARL pathogenesis, we analyzed viral gene expression and found highly heterogeneous patterns of viral transcription across samples. We also found significant heterogeneity of viral antigen expression across a large cohort, with many patient samples presenting with restricted type I viral latency, indicating that EBV latency proteins are under increased immunosurveillance in the post-combined antiretroviral therapies era. Furthermore, EBV infection of lymphoma cells in HIV-positive individuals was associated with a distinct host gene expression program. These findings provide insight into the joint host-virus regulatory network of primary ARL tumor samples and expand our understanding of virus-associated oncogenesis. Our findings may also have therapeutic implications, as treatment may be personalized to target specific viral and virus-associated host processes that are only present in a subset of patients. PMID:25827832

  16. Topotecan Hydrochloride in Treating Children With Meningeal Cancer That Has Not Responded to Previous Treatment

    ClinicalTrials.gov

    2013-02-20

    AIDS-related Diffuse Large Cell Lymphoma; AIDS-related Diffuse Mixed Cell Lymphoma; AIDS-related Diffuse Small Cleaved Cell Lymphoma; AIDS-related Immunoblastic Large Cell Lymphoma; AIDS-related Lymphoblastic Lymphoma; AIDS-related Peripheral/Systemic Lymphoma; AIDS-related Primary CNS Lymphoma; AIDS-related Small Noncleaved Cell Lymphoma; Childhood Diffuse Large Cell Lymphoma; Childhood Immunoblastic Large Cell Lymphoma; HIV-associated Hodgkin Lymphoma; Leptomeningeal Metastases; Recurrent Childhood Acute Lymphoblastic Leukemia; Recurrent Childhood Acute Myeloid Leukemia; Recurrent Childhood Large Cell Lymphoma; Recurrent Childhood Lymphoblastic Lymphoma; Recurrent Childhood Medulloblastoma; Recurrent Childhood Small Noncleaved Cell Lymphoma; Recurrent/Refractory Childhood Hodgkin Lymphoma; Unspecified Childhood Solid Tumor, Protocol Specific

  17. Psychological Consequences of AIDS-Related Bereavement among Gay Men.

    ERIC Educational Resources Information Center

    Martin, John L.

    1988-01-01

    Interviewed 745 homosexual men to examine relation between Acquired Immune Deficiency Syndrome (AIDS)-related bereavement and psychological distress. Loss of lover or close friend to AIDS was reported by 27 percent of sample. Found direct relation between number of bereavements and symptoms of traumatic stress response, demoralization, sleep…

  18. HIV/AIDS-related stigma in Kumasi, Ghana

    PubMed Central

    Ulasi, Chijioke I; Preko, Peter O; Baidoo, Joseph A.; Bayard, Budry; Ehiri, John E; Jolly, Curtis M; Jolly, Pauline E

    2009-01-01

    Objective To assess HIV/AIDS-related stigma and discrimination of people living with HIV/AIDS (PLWHA) in Kumasi, Ghana. Methods A cross-sectional survey of 104 adults from the four sub-districts in Kumasi was conducted. Results Four stigma constructs, employment-based discrimination, screening and identification of HIV positive people, revelation of HIV status and social contact stigma were determined based on reliability measures from responses to the questionnaire. Regression analysis showed that participants with higher educational attainment were more likely to favor policies denying employment to PLWHA (p<0.05), but disapproved of revealing HIV sero-status (p<0.05). Muslims were more likely than Christians to agree with identifying PLWHA (p<0.05) and more likely to advocate revealing HIV sero-status (p<0.05). Males were more likely to favor revealing HIV status (p<0.05). Employed persons were more likely to have social contact with PLWHA (p<0.05). Conclusions These findings are useful in guiding the design of interventions against HIV/AIDS-related stigma in Kumasi. PMID:18632302

  19. AIDS related knowledge and behaviours among college students, Gondar, Ethiopia: a comparative study.

    PubMed

    Teka, T

    1997-07-01

    AIDS-related knowledge and behaviours among students at the Gondar College of Medical Sciences, Gondar, Ethiopia were evaluated based on identical surveys conducted in 1990 and 1992. One hundred three second year students provided information in 1992. Analysis indicated that 49% were engaged in sexual intercourse and only a third of these group used condom despite their improved knowledge and belief on condom compared to their previous position in 1990 (p < 0.004). On the other hand, their sexual behaviours regarding sexual contact with high risk individuals decreased compared to 1990 (p < 0.0005). Their general level of AIDS-related preventive knowledge increased over time (p < 0.002), although there was no significant difference in knowledge observed among different sexes and departments. Among the sexually active, a large proportion of students (22%) still had sexual contact with high risk individuals and only 33% of them were using safer methods. Continuing efforts, including peer education, specific health education interventions are still crucially needed to bring a positive change in sexual behaviour. PMID:9558757

  20. Detection of polyomavirus simian virus 40 tumor antigen DNA in AIDS-related systemic non-Hodgkin lymphoma

    NASA Technical Reports Server (NTRS)

    Vilchez, Regis A.; Lednicky, John A.; Halvorson, Steven J.; White, Zoe S.; Kozinetz, Claudia A.; Butel, Janet S.

    2002-01-01

    Systemic non-Hodgkin lymphoma (S-NHL) is a common malignancy during HIV infection, and it is hypothesized that infectious agents may be involved in the etiology. Epstein-Barr virus DNA is found in <40% of patients with AIDS-related S-NHL, suggesting that other oncogenic viruses, such as polyomaviruses, may play a role in pathogenesis. We analyzed AIDS-related S-NHL samples, NHL samples from HIV-negative patients, peripheral blood leukocytes from HIV-infected and -uninfected patients without NHL, and lymph nodes without tumors from HIV-infected patients. Specimens were examined by polymerase chain reaction analysis with use of primers specific for an N-terminal region of the oncoprotein large tumor antigen ( T-ag ) gene conserved among all three polyomaviruses (simian virus 40 [SV40], JC virus, and BK virus). Polyomavirus T-ag DNA sequences, proven to be SV40-specific, were detected more frequently in AIDS-related S-NHL samples (6 of 26) than in peripheral blood leukocytes from HIV-infected patients (6 of 26 vs. 0 of 69; p =.0001), NHL samples from HIV-negative patients (6 of 26 vs. 0 of 10; p =.09), or lymph nodes (6 of 26 vs. 0 of 7; p =.16). Sequences of C-terminal T-ag DNA from SV40 were amplified from two AIDS-related S-NHL samples. Epstein-Barr virus DNA sequences were detected in 38% (10 of 26) AIDS-related S-NHL samples, 50% (5 of 10) HIV-negative S-NHL samples, and 57% (4 of 7) lymph nodes. None of the S-NHL samples were positive for both Epstein-Barr virus DNA and SV40 DNA. Further studies of the possible role of SV40 in the pathogenesis of S-NHL are warranted.

  1. Measuring HIV/AIDS-Related Stigma across South Africa: A Versatile and Multidimensional Scale

    ERIC Educational Resources Information Center

    Smith, Edward A.; Miller, Jacqueline A.; Newsome, Valerie; Sofolahan, Yewande A.; Airhihenbuwa, Collins O.

    2014-01-01

    Reducing HIV/AIDS-related stigma is critical in the fight against HIV/AIDS. Although national campaigns and prevention programs have been implemented across South Africa to address this critical concern, assessing the impact of these initiatives is difficult as it requires that measurement of HIV/AIDS-related stigma is uniform and comparable…

  2. Balancing engagement/detachment in AIDS-related multiple losses.

    PubMed

    Carmack, B J

    1992-01-01

    The process gay persons use to manage the multiple losses and cumulative grief from losing lovers, friends, colleagues and clients to AIDS was explored. Interviews with gay individuals (n = 19) in a large urban area in the West provided data for conceptual coding and comparative analysis. Balancing engagement and detachment was identified as the basic social-psychological process that described how gay individuals struggled to reach an optimal balance in their involvement in the needs of individuals and the community. Four conceptual categories were identified: dysfunctional engagement, functional engagement, functional detachment and dysfunctional detachment. These four categories occur within the contexts of previous life style and redefinition of personal values. PMID:1541482

  3. Recent advances in the treatment of AIDS-related Kaposi's sarcoma.

    PubMed

    Cattelan, Anna M; Trevenzoli, Marco; Aversa, Savina M L

    2002-01-01

    Kaposi's sarcoma (KS) is the most common malignancy associated with HIV infection and is considered an AIDS defining condition by the US Centers of Disease Control Guidelines. Several advances in the treatment of AIDS-related KS have been achieved over the past few years, even though a gold standard therapy for KS has not yet been defined and treatment must be tailored to individual needs. Since the availability of highly active antiretroviral therapy (HAART), a dramatic clinical response has been documented in patients with KS, making HAART an essential approach in the management of KS in most, if not all, patients with AIDS-related KS. However, in case of aggressive, visceral, and/or life-threatening KS, more complex therapeutic schedules have to be taken into account, including chemotherapy, radiotherapy, and/or immunotherapy. In general, systemic treatment for KS is limited to widespread, symptomatic disease, whereas local interventions are indicated for minimal, cosmetically troublesome lesions. Among new cytotoxic agents, liposomal anthracyclines and paclitaxel are highly effective molecules for KS and have been approved by the US Food and Drug Administration (FDA) as first-line and second-line monotherapy, respectively, for advanced KS. Furthermore, a greater understanding of the pathogenesis of KS has lead to the development of an array of new experimental agents. Many antiangiogenic agents such as AGM 1470 (TNP 470), thalidomide, and glufanide disodium (IM 862) have produced encouraging responses in patients with KS and large clinical trials are in progress. Retinoic acids may also block neoangiogenesis as well as proliferation of KS cells in vitro, and they have been used either systemically or topically with a high response rate. Thus, a topical compound 0.1% alitretinoin gel was approved in 1999 by the FDA for the treatment of skin lesions associated with KS. Human chorionic gonadotropin, a hormonal agent, has shown a strong inhibitory activity in KS

  4. Expression of immunohistochemical markers in patients with AIDS-related lymphoma.

    PubMed

    Barreto, Luciana; Azambuja, Denize; Morais, José Carlos de

    2012-01-01

    AIDS-related lymphomas (ARL) present high biological heterogeneity. For better characterization of this type of lymphoma, the objectives of the present study were to evaluate the expression of immunohistochemical markers of cell differentiation (CD10, Bcl-6, MUM-1) and determine cell origin profile according to Hans' classification of diffuse large B-cell lymphoma in AIDS patients. This study included 72 consecutive patients with ARL diagnosed at the University Hospital, Universidade Federal do Rio de Janeiro (UFRJ) and at the Brazilian Instituto Nacional de Câncer (INCA) from 2000 to 2006. The morphologic distribution of the lymphomas was the following: 61% were diffuse large B-cell lymphomas (DLBCLs), 15% were Burkitt's lymphomas, 13% were plasmablastic lymphomas, 10% were high-grade lymphomas and 1% was follicular lymphoma. The positivity for each immunohistochemical marker in DLBCLs, Burkitt's lymphoma and plasmablastic lymphoma was respectively: CD20, 84%, 100%, and 0; CD10, 55%, 100%, and 0; Bcl-6, 45%, 80%, and 0; MUM-1, 41%, 20%, and 88%. A higher positivity of CD20 (84% x 56%, p = 0.01) was found in DLBCL compared to non-DLBCL; in Burkitt's lymphomas a higher positivity of CD10 (100% x 49%, p = 0.04) and Bcl-6 (80% x 39%, p = 0.035) were found compared to non-Burkitt's lymphomas. Germinal center (GC) profile was detected in 60% of DLBCLs. Our study suggests particular findings in ARL, as the most frequent phenotype was GC, different from HIV-negative patients. PMID:22358360

  5. Endoscopic appearance of AIDS-related gastrointestinal lymphoma with c-MYC rearrangements: Case report and literature review

    PubMed Central

    Tanaka, Shohei; Nagata, Naoyoshi; Mine, Sohtaro; Igari, Toru; Kobayashi, Taiichiro; Sugihara, Jun; Honda, Haruhito; Teruya, Katsuji; Kikuchi, Yoshimi; Oka, Shinichi; Uemura, Naomi

    2013-01-01

    Acquired immune deficiency syndrome (AIDS)-related lymphoma (ARL) remains the main cause of AIDS-related deaths in the highly active anti-retroviral therapy (HAART) era. Recently, rearrangement of MYC is associated with poor prognosis in patients with diffuse large B-cell lymphoma. Here, we report a rare case of gastrointestinal (GI)-ARL with MYC rearrangements and coinfected with Epstein-Barr virus (EBV) infection presenting with various endoscopic findings. A 38-year-old homosexual man who presented with anemia and was diagnosed with an human immunodeficiency virus infection for the first time. GI endoscopy revealed multiple dish-like lesions, ulcerations, bloody spots, nodular masses with active bleeding in the stomach, erythematous flat lesions in the duodenum, and multiple nodular masses in the colon and rectum. Magnified endoscopy with narrow band imaging showed a honeycomb-like pattern without irregular microvessels in the dish-like lesions of the stomach. Biopsy specimens from the stomach, duodenum, colon, and rectum revealed diffuse large B-cell lymphoma concomitant with EBV infection that was detected by high tissue EBV-polymerase chain reaction levels and Epstein-Barr virus small RNAs in situ hybridization. Fluorescence in situ hybridization analysis revealed a fusion between the immunoglobulin heavy chain (IgH) and c-MYC genes, but not between the IgH and BCL2 loci. After 1-mo of treatment with HAART and R-CHOP, endoscopic appearance improved remarkably, and the histological features of the biopsy specimens revealed no evidence of lymphoma. However, he died from multiple organ failure on the 139th day after diagnosis. The cause of his poor outcome may be related to MYC rearrangement. The GI tract involvement in ARL is rarely reported, and its endoscopic findings are various and may be different from those in non-AIDS GI lymphoma; thus, we also conducted a literature review of GI-ARL cases. PMID:23922484

  6. Endoscopic appearance of AIDS-related gastrointestinal lymphoma with c-MYC rearrangements: case report and literature review.

    PubMed

    Tanaka, Shohei; Nagata, Naoyoshi; Mine, Sohtaro; Igari, Toru; Kobayashi, Taiichiro; Sugihara, Jun; Honda, Haruhito; Teruya, Katsuji; Kikuchi, Yoshimi; Oka, Shinichi; Uemura, Naomi

    2013-08-01

    Acquired immune deficiency syndrome (AIDS)-related lymphoma (ARL) remains the main cause of AIDS-related deaths in the highly active anti-retroviral therapy (HAART) era. Recently, rearrangement of MYC is associated with poor prognosis in patients with diffuse large B-cell lymphoma. Here, we report a rare case of gastrointestinal (GI)-ARL with MYC rearrangements and coinfected with Epstein-Barr virus (EBV) infection presenting with various endoscopic findings. A 38-year-old homosexual man who presented with anemia and was diagnosed with an human immunodeficiency virus infection for the first time. GI endoscopy revealed multiple dish-like lesions, ulcerations, bloody spots, nodular masses with active bleeding in the stomach, erythematous flat lesions in the duodenum, and multiple nodular masses in the colon and rectum. Magnified endoscopy with narrow band imaging showed a honeycomb-like pattern without irregular microvessels in the dish-like lesions of the stomach. Biopsy specimens from the stomach, duodenum, colon, and rectum revealed diffuse large B-cell lymphoma concomitant with EBV infection that was detected by high tissue EBV-polymerase chain reaction levels and Epstein-Barr virus small RNAs in situ hybridization. Fluorescence in situ hybridization analysis revealed a fusion between the immunoglobulin heavy chain (IgH) and c-MYC genes, but not between the IgH and BCL2 loci. After 1-mo of treatment with HAART and R-CHOP, endoscopic appearance improved remarkably, and the histological features of the biopsy specimens revealed no evidence of lymphoma. However, he died from multiple organ failure on the 139(th) day after diagnosis. The cause of his poor outcome may be related to MYC rearrangement. The GI tract involvement in ARL is rarely reported, and its endoscopic findings are various and may be different from those in non-AIDS GI lymphoma; thus, we also conducted a literature review of GI-ARL cases. PMID:23922484

  7. Brief Report: Role of Thymic Reconstitution in the Outcome of AIDS-Related PML.

    PubMed

    Chalkias, Spyridon G; Gheuens, Sarah; Bord, Evelyn; Batson, Stephanie; Koralnik, Igor J

    2015-12-01

    Implications of thymopoiesis in AIDS-related opportunistic infections remain unexplored. We used progressive multifocal leukoencephalopathy (PML), caused by JC virus (JCV), as an opportunistic infection model, and we simultaneously investigated thymic output and T-cell responses against JCV in 22 patients with PML treated with combined antiretroviral therapy. Thymic output was significantly associated with JCV-specific CD4⁺ and CD8⁺ T-cell responses and improved survival. Our data suggest that patients with AIDS-related PML and impaired thymopoiesis are less likely to develop a robust JCV-specific cellular immune response and consequently are at an increased risk for a poor clinical outcome. PMID:26181821

  8. Predicting AIDS-related events using CD4 percentage or CD4 absolute counts

    PubMed Central

    Pirzada, Yasmin; Khuder, Sadik; Donabedian, Haig

    2006-01-01

    Background The extent of immunosuppression and the probability of developing an AIDS-related complication in HIV-infected people is usually measured by the absolute number of CD4 positive T-cells. The percentage of CD4 positive cells is a more easily measured and less variable number. We analyzed sequential CD4 and CD8 numbers, percentages and ratios in 218 of our HIV infected patients to determine the most reliable predictor of an AIDS-related event. Results The CD4 percentage was an unsurpassed predictor of the occurrence of AIDS-related events when all subsets of patients are considered. The CD4 absolute count was the next most reliable, followed by the ratio of CD4/CD8 percentages. The value of CD4 percentage over the CD4 absolute count was seen even after the introduction of highly effective HIV therapy. Conclusion The CD4 percentage is unsurpassed as a parameter for predicting the onset of HIV-related diseases. The extra time and expense of measuring the CD4 absolute count may be unnecessary. PMID:16916461

  9. AIDS-Related Factors Predictive of Suicidal Ideation of Low and High Intent among Gay and Bisexual Men.

    ERIC Educational Resources Information Center

    Schneider, Stephen G.; And Others

    1991-01-01

    Studied Acquired Immune Deficiency Syndrome (AIDS)-related stressors and suicidal ideation/intent among 778 gay and bisexual men (none with AIDS). Compared to those who reported no suicidal ideation over past six months, those who reported ideation (n=212) were more likely to report recent bereavement of partner, AIDS-Related Disorder (ARC)…

  10. Productive human immunodeficiency virus infection levels correlate with AIDS-related manifestations in the patient

    SciTech Connect

    Mathez, D.; Paul, D.; de Belilovsky, C.; Sultan, Y.; Deleuze, J.; Gorin, I.; Saurin, W.; Decker, R.; Leibowitch, J. )

    1990-10-01

    Mononuclear cells were obtained from 71 human immunodeficiency virus type 1 (HIV-1) seropositive subjects presenting and first visit either as asymptomatic or with minor symptoms and with CD4 lymphocytes greater than 550 per mm3 (group A, 35 patients) or as patients with AIDS, AIDS-related illnesses, or CD4 lymphocytes less than 400 per mm3 (group B, 36 patients). After 1-5 years of follow-up, 13 patients of group A had essentially retained their initial status (asymptomatics); the 22 others had suffered clinical or immunological deterioration (progressors). Frozen cells were thawed and submitted to lethal gamma-irradiation in vitro (4500 rads; 1 rad = 0.01 Gy) before they were cultured with normal phytohemagglutinin-stimulated lymphocytes to determine radiation-resistant HIV expression ex vivo (R-HEV). HIV antigenemia correlated with R-HEV values in 142 samples (r = 0.92, P less than 0.001) but was a less sensitive predictor of disease than R-HEV. R-HEV was detected in all specimens from patients with major AIDS-related illnesses or HIV-associated CD4 lymphopenia. In 77% of the progressors from group A, R-HEV detection preceded the onset of AIDS-associated disease or CD4 lymphopenia by 1 year (average). Conversely, R-HEV was low or was not detected in 36 sequential specimens from the 13 patients who remained asymptomatic over the following 2-5 years. Thus, persistently low HIV expression in vivo predicted a nondiseased state, whereas higher HIV expression levels seemed necessary for disease to occur. These data indicate that R-HEV is related to productive HIV infection in vivo, the latter acting as a determinant of AIDS-related illnesses. In view of this, measurement of HIV expression levels in the patient should be useful in antiviral efficacy trials.

  11. Patterns of gallium-67 scintigraphy in patients with acquired immunodeficiency syndrome and the AIDS related complex

    SciTech Connect

    Bitran, J.; Bekerman, C.; Weinstein, R.; Bennett, C.; Ryo, U.; Pinsky, S.

    1987-07-01

    Thirty-two patients with AIDS related complex (ARC) or acquired immunodeficiency syndrome (AIDS) underwent /sup 67/Ga scans as part of their evaluation. Three patterns of /sup 67/Ga biodistribution were found: lymph node uptake alone; diffuse pulmonary uptake; normal scan. Gallium-67 scans were useful in identifying clinically occult Pneumocystis carinii pneumonia in seven of 15 patients with ARC who were asymptomatic and had normal chest radiographs. Gallium scans are a useful ancillary procedure in the evaluation of patients with ARC or AIDS.

  12. AIDS-related knowledge, attitudes, and behaviors among juvenile delinquents in Israel.

    PubMed

    Slonim-Nevo, V

    Fifty-six Israeli adolescents under the care of probation officers were interviewed about their AIDS-related knowledge, attitudes, and behaviors. The results suggest that these adolescents put themselves at risk of HIV infection. A substantial proportion of the sample demonstrated a lack of knowledge on issues relevant for AIDS prevention. The majority held negative attitudes toward condoms but were also sexually active, and some had experienced unprotected sexual intercourse, anal sex, and drug use. Most of the respondents, moreover, showed a lack of competence in handling situations that pressure them to act unsafely. Implications for practice are discussed. PMID:1343361

  13. Photodynamic therapy for treatment of AIDS-related mucocutaneous Kaposi's sarcoma (Invited Paper)

    NASA Astrophysics Data System (ADS)

    Schweitzer, Vanessa G.

    1992-06-01

    Since 1975, Phase I/II studies have demonstrated the successfulness of hematoporphyrin derivative photodynamic therapy (PDT) in the treatment of various malignancies of the skin, eye, bladder, lung, and head and neck. Moreover, in 1981 two cases of traditional Western cutaneous Kaposi's sarcoma (TKS) have been treated with photodynamic therapy with both early and late complete response. To date, attempts to cure and palliation of the more aggressive AIDS-related oral Kaposi's sarcoma with conventional radiation, chemotherapy or immunotherapy, or surgical excision have been limited and often associated with debilitating mucositis and further immunosuppression. Certain aspects of photodynamic therapy may be efficacious for treatment of mucocutaneous Kaposi's sarcoma: (1) the selective retention of hematoporphyrin derivative by neoplastic lesions (endothelial cell tumors); (2) a tumor- specific cytotoxic agent (i.e., free oxygen radical); (3) absence of systemic toxicity from immunosuppression; (4) the potential for retreatment without increasing side effects; and (5) porphyrin-mediated photoinactivation of enveloped viruses. Herein presented are seven cases of AIDS-related KS (EKS) with diffuse, superficial, and nodular mucocutaneous lesions treated with dihematoporphyrin derivative and photodynamic therapy with subsequent dramatic early partial and complete responses.

  14. Economic empowerment and AIDS-related stigma in rural Kenya: a double-edged sword?

    PubMed

    Gnauck, Katherine; Ruiz, Jamie; Kellett, Nicole; Sussman, Andrew; Sullivan, Mary Ann; Montoya, Maria; Levin, Nick; Tomedi, Angelo; Mwanthi, Mutuku A

    2013-01-01

    Economic empowerment, HIV risk and AIDS-related stigma appear intricately intertwined for women in Kenya. Their interaction must be understood in order to implement effective economic interventions that also decrease HIV risk and stigma. We conducted a qualitative study amongst women in a rural Kamba-speaking community of southeastern Kenya to pursue whether engagement in an economic empowerment initiative (a basket weaving cooperative) influences women's perspectives and experiences with HIV risk and AIDS-related stigma. We conducted seven women's focus groups: participants in the local basket-weaving cooperative comprised four focus groups and non-participants comprised the remaining three groups. The HIV status of the women was not known. Three dominant themes emerged from the focus groups: empowerment, pervasive vulnerability and unanticipated social paradoxes. Contradictions found in these themes suggest that economic empowerment can become a double-edged sword. Economic empowerment enhanced perceived individual, domestic and social community status. However, this enhancement was not protective of domestic violence and perceived HIV risk. Social perceptions may have paradoxically contributed barriers to HIV testing and treatment putting women at greater HIV risk. In conclusion, economic empowerment initiatives for women in developing countries in the context of the HIV epidemic should be coupled with peer mediated support and HIV-risk education. PMID:23668536

  15. HIV and AIDS-related stigma and discrimination: a conceptual framework and implications for action.

    PubMed

    Parker, Richard; Aggleton, Peter

    2003-07-01

    Internationally, there has been a recent resurgence of interest in HIV and AIDS-related stigma and discrimination, triggered at least in part by growing recognition that negative social responses to the epidemic remain pervasive even in seriously affected communities. Yet, rarely are existing notions of stigma and discrimination interrogated for their conceptual adequacy and their usefulness in leading to the design of effective programmes and interventions. Taking as its starting point, the classic formulation of stigma as a 'significantly discrediting' attribute, but moving beyond this to conceptualize stigma and stigmatization as intimately linked to the reproduction of social difference, this paper offers a new framework by which to understand HIV and AIDS-related stigma and its effects. It so doing, it highlights the manner in which stigma feeds upon, strengthens and reproduces existing inequalities of class, race, gender and sexuality. It highlights the limitations of individualistic modes of stigma alleviation and calls instead for new programmatic approaches in which the resistance of stigmatized individuals and communities is utilized as a resource for social change. PMID:12753813

  16. Responding to AIDS-related bereavement in the South African context.

    PubMed

    Demmer, Craig

    2007-10-01

    AIDS continues to be a death sentence for many individuals living in South Africa where it remains the leading cause of death. Little is currently known about what it is like to experience the loss of a loved one to AIDS from the South African perspective and how to assist individuals who are living in a context vastly different from similarly bereaved individuals in the West. The purpose of this article is to discuss contextual issues that may affect individuals in South Africa who are grieving AIDS-related deaths and to offer preliminary suggestions on how to help these individuals. The author draws on his experience in the province of KwaZulu-Natal working with people affected by the HIV/AIDS epidemic, as well as discussions with practitioners involved in HIV/AIDS care in this region. PMID:17886413

  17. Gender and AIDS-related psychosocial processes: a study of perceived susceptibility, social distance, and homophobia.

    PubMed

    Schieman, S

    1998-06-01

    Over the past decade, researchers have accumulated evidence that suggests six main factors are associated with AIDS-related risk reduction behavior: (a) perceived susceptibility (Dolcini et al., 1995; van der Plight & Richard, 1994); (b) attitudes toward condoms (Catania et al., 1994; Maticka-Tynadale, 1991); (c) personally knowing someone with HIV/AIDS (Joseph et al., 1987); (d) perceived peer norms about risk-reduction (Maticka-Tyndale, 1991); (e) previous sexual activity (Joseph et al., 1987); and (f) self-efficacy (Aspinwall, Kemeny, Taylor, & Schneider, 1991; van der Plight & Richard, 1994). Furthermore, there is some suggestion that the epidemiology and sociocultural constructions of the disease has led to considerable gender, racial, and class differences in awareness of AIDS, perception of HIV threat, and HIV-relevant behavior (Cohan & Atwood, 1994; Dolcini et al., 1995; Gillies, 1994). PMID:9642424

  18. Understanding and Addressing AIDS-Related Stigma: From Anthropological Theory to Clinical Practice in Haiti

    PubMed Central

    Castro, Arachu; Farmer, Paul

    2005-01-01

    For the past several years, diverse and often confused concepts of stigma have been invoked in discussions on AIDS. Many have argued compellingly that AIDS-related stigma acts as a barrier to voluntary counseling and testing. Less compelling are observations regarding the source of stigma or its role in decreasing interest in HIV care. We reviewed these claims as well as literature from anthropology, sociology, and public health. Preliminary data from research in rural Haiti suggest that the introduction of quality HIV care can lead to a rapid reduction in stigma, with resulting increased uptake of testing. Rather than stigma, logistic and economic barriers determine who will access such services. Implications for scale-up of integrated AIDS prevention and care are explored. PMID:15623859

  19. Successful treatment with autologous peripheral blood stem cell transplantation for acquired immunodeficiency syndrome (AIDS)-related malignant lymphoma.

    PubMed

    NAGAI, Yuya; MORI, Minako; INOUE, Daichi; KIMURA, Takaharu; SHIMOJI, Sonoko; TOGAMI, Katsuhiro; TABATA, Sumie; MATSUSHITA, Akiko; NAGAI, Kenichi; Imai, Yukihiro; Takafuta, Toshiro; Takahashi, Takayuki

    2009-11-01

    A 62-year-old man was diagnosed with human immunodeficiency virus (HIV) infection while suffering from recurrent herpes zoster infection. Laboratory examination revealed CD4(+) lymphocyte count 16 cells/mul and HIV loading 150,000 copies/ml at presentation. In addition, he had multiple lymph node swelling. Histologic diagnosis of a biopsied lymph node was diffuse, large, B cell-type malignant lymphoma. The karyotype of the lymphoma cells was t(8;14)(q24;q32), which was confirmed by G-banding and fluorescent in situ hybridization. Positron emission tomography (PET)-combined CT scanning revealed systemic extranodal tumors involving the gastrointestinal tract, pancreas, and bone marrow. The clinical stage of the lymphoma was IVB and the international prognosis index was categorized as high. Complete remission (CR) of the lymphoma was obtained after 2 courses of CHOP (cyclophosphamide, adriamycin, vincristine, prednisolone) chemotherapy and 4 subsequent courses of rituximab-combined CHOP (R-CHOP). Highly active antiretroviral therapy (HAART) was started at the initiation of CHOP. Because of the poor prognosis of AIDS-related lymphoma, he received autologous peripheral blood stem cell transplantation with the MEAM protocol (ranimustine, etoposide, cytarabine, melphalan) as a conditioning procedure without a severe infectious episode. He remains in CR 24 months after the transplantation. PMID:20009441

  20. AIDS-related knowledge, attitudes and behaviour among South African street youth: reflections on power, sexuality and the autonomous self.

    PubMed

    Swart-Kruger, J; Richter, L M

    1997-09-01

    Street children in South Africa are, in the main, between the ages of 11 and 17 years. Rape, prostitution, sexual bartering and exchange, casual sex and romantic sexual relationships all occur in the experiences of young people who live and work on inner-city streets. In this study, the AIDS-related knowledge, attitudes and behaviour of 141 street youth, living in seven large cities in South Africa, were elicited in focus group discussions. At the time of the study, 79 boys (56%) were living in shelters run by nongovernmental and welfare organisations, while 62 boys (44%) were sleeping "rough". The results, both qualitative and quantitative, indicated that the AIDS knowledge of South African street children was comparable to levels reported for groups of "hard-to-reach" youth in other parts of the world. Fear of HIV infection did not appear in a list of day-to-day priorities constructed by the children, a list dominated by survival concerns with food, money and clothes. However, more than half of the boys conceded that they engaged in sex for money, goods or protection, several boys indicated that they had been raped, and most reported being sexually active with "girlfriends", who themselves frequently engaged in transactional sex. The findings are interpreted in terms of the relationships between power dynamics surrounding race and age, and how they affect self-initiated controls over sexuality and sexual protection. PMID:9255928

  1. A systematic review of HIV/AIDS-related stigma and discrimination in India: current understanding and future needs.

    PubMed

    Bharat, Shalini

    2011-01-01

    HIV/AIDS-related stigma is recognised as a major barrier to HIV prevention efforts and an impediment to mitigating its impact on individuals and communities. This paper reviews the existing research literature on AIDS stigma in India with the objective of documenting the current status of research, highlighting major findings and identifying key gaps remaining. Thirty publications were identified through a careful search of which a majority focused on stigma assessment and very few on stigma measurement, conceptual aspects of stigma or stigma reduction interventions. A few standardised stigma measures are available but more are required to assess causes of stigma among general population and compounded and internalised stigma among positive people. Research exploring linkages between stigma and HIV services uptake or the effect of HIV care and treatment programs on stigma levels are largely missing and need to be prioritised. In addition, more research is needed to advance conceptual understanding of stigma within the cultural context of the country including research on the neglected groups such as, transgender people. Context-specific (health care, community) interventions are needed to address various forms of stigma - enacted, perceived, internalised and layered - including structural approaches besides inter-personal and information-based approaches. A major gap relates to meager research on developing and evaluating stigma reduction interventions and needs priority focus. Overall, the review recommends developing a national agenda on AIDS stigma research and interventions to help realise the government's goal of stigma reduction. PMID:23237728

  2. Understanding Internalized HIV/AIDS-Related Stigmas in the Dominican Republic: A Short Report

    PubMed Central

    Hampanda, Karen

    2016-01-01

    HIV/AIDS-related stigmas can become internalized, resulting in declines in physical and mental health. Pathways to internalized HIV-related stigma (IS), characterized by persistently negative, self-abasing thoughts, are not well established among women living with HIV/AIDS (WLWHA) in the Dominican Republic (DR). Identifying factors involved in self-directed shaming and blaming is important, given the high HIV prevalence in the DR’s most vulnerable populations. The present study sheds light on factors involved in negative and self-abasing thoughts in WLWHA in the DR by examining the relationship between depression, perceived HIV-related stigma from the community (PSC), perceived HIV-related stigma from family (PSF) and IS. The Internalized AIDS-Related Stigma Scale (IA-RSS), the Center for Epidemiologic Studies Short Depression Scale (CES-D 10), and an instrument designed to measure perceived HIV-related stigma from the community and family was administered to 233 WLWHA in Puerto Plata, DR. Data were analyzed using descriptive statistics and ordered multiple logistic regression. Results showed that depression (OR=1.60; p<0.05), PSC (OR=3.68; p<0.001), and PSF (OR=1.60; p<0.01) were positively associated with IS. These findings indicate that IS-reducing interventions should address HIV-related depression. Additionally, HIV-related treatment and care services should work with WLWHA to adopt healthier attitudes about how community members view people living with HIV/AIDS in the Dominican Republic. PMID:26466239

  3. Understanding internalized HIV/AIDS-related stigmas in the Dominican Republic: a short report.

    PubMed

    Rael, Christine Tagliaferri; Hampanda, Karen

    2016-03-01

    HIV/AIDS-related stigmas can become internalized, resulting in declines in physical and mental health. Pathways to internalized HIV-related stigma (IS), characterized by persistently negative, self-abasing thoughts, are not well established among women living with HIV/AIDS (WLWHA) in the Dominican Republic (DR). Identifying factors involved in self-directed shaming and blaming is important, given the high HIV prevalence in the DR's most vulnerable populations. The present study sheds light on factors involved in negative and self-abasing thoughts in WLWHA in the DR by examining the relationship between depression, perceived HIV-related stigma from the community (PSC), perceived HIV-related stigma from family (PSF), and IS. The Internalized AIDS-Related Stigma Scale (IA-RSS), the Center for Epidemiologic Studies Short Depression Scale (CES-D 10), and an instrument designed to measure perceived HIV-related stigma from the community and family was administered to 233 WLWHA in Puerto Plata, DR. Data were analyzed using descriptive statistics and ordered multiple logistic regression. Results showed that depression (OR = 1.60; p < .05), PSC (OR = 3.68; p < .001), and PSF (OR = 1.60; p < .01) were positively associated with IS. These findings indicate that IS-reducing interventions should address HIV-related depression. Additionally, HIV-related treatment and care services should work with WLWHA to adopt healthier attitudes about how community members view people living with HIV/AIDS in the DR. PMID:26466239

  4. Circulating Mediators of Inflammation and Immune Activation in AIDS-Related Non-Hodgkin Lymphoma

    PubMed Central

    Nolen, Brian M.; Breen, Elizabeth Crabb; Bream, Jay H.; Jenkins, Frank J.; Kingsley, Lawrence A.; Rinaldo, Charles R.; Lokshin, Anna E.

    2014-01-01

    Background Non-Hodgkin lymphoma (NHL) is the most common AIDS-related malignancy in developed countries. An elevated risk of developing NHL persists among HIV-infected individuals in comparison to the general population despite the advent of effective antiretroviral therapy. The mechanisms underlying the development of AIDS-related NHL (A-NHL) are not fully understood, but likely involve persistent B-cell activation and inflammation. Methods This was a nested case-control study within the ongoing prospective Multicenter AIDS Cohort Study (MACS). Cases included 47 HIV-positive male subjects diagnosed with high-grade B-cell NHL. Controls were matched to each case from among participating HIV-positive males who did not develop any malignancy. Matching criteria included time HIV+ or since AIDS diagnosis, age, race and CD4+ cell count. Sera were tested for 161 serum biomarkers using multiplexed bead-based immunoassays. Results A subset of 17 biomarkers, including cytokines, chemokines, acute phase proteins, tissue remodeling agents and bone metabolic mediators was identified to be significantly altered in A-NHL cases in comparison to controls. Many of the biomarkers included in this subset were positively correlated with HIV viral load. A pathway analysis of our results revealed an extensive network of interactions between current and previously identified biomarkers. Conclusions These findings support the current hypothesis that A-NHL develops in the context of persistent immune stimulation and inflammation. Further analysis of the biomarkers identified in this report should enhance our ability to diagnose, monitor and treat this disease. PMID:24922518

  5. The political context of AIDS-related stigma and knowledge in a South African township community.

    PubMed

    Forsyth, Brian; Vandormael, Alain; Kershaw, Trace; Grobbelaar, Janis

    2008-07-01

    The purpose of this study was to examine the presentation of AIDS-related stigma and knowledge within the political context of the South African government's response to the AIDS epidemic. It was during the 2000 - 2004 period that key government officials publicly challenged the orthodox views of HIV/AIDS, with the South African president, Thabo Mbeki, actively positing the primary role of poverty and other socio-economic stressors in the progression of the AIDS epidemic. This discursive position had real-time effects for AIDS policy-making and ultimately delayed the implementation of a national antiretroviral (ARV) rollout programme. Consequently this position was criticised by commentators in the media and elsewhere for contributing to an already widespread climate of AIDS stigmatization and misinformation. To shed more light on these claims we conducted a survey in 2005 in Atteridgeville, a South African township, and compared results with those of a similar survey conducted shortly after ARV medications became available in 2004. Results indicated a reduction in AIDS stigma levels across the 1-year period, and that those participants who endorsed contentious political views (such as those expressed by key government officials) were more likely to have a higher level of AIDS-related stigma than those who disagreed. Nevertheless, this study cautions against drawing a causal relationship between the South African government's position and IDS-stigmatizing attitudes, and suggests that further political and social factors be accounted for in an attempt to gain a fuller understanding of this seemingly complex relationship. PMID:18709210

  6. AIDS as social construction: text mining of AIDS-related information in the Italian press.

    PubMed

    Caputo, Andrea; Giacchetta, Agnese; Langher, Viviana

    2016-09-01

    Given the relevance of AIDS as a public health problem in the Italian context and of the role of mass media in the social construction of the phenomenon, the aim of the present study is twofold: (1) to explore the main AIDS-related themes in the Italian popular press; (2) to analyse the temporal trends of AIDS representations over the last decades. For the research, we decided to consult Italian newspaper articles produced between 1985 and 1990 and between 2005 and 2010 using the archives of the main two national newspapers (La Repubblica and Corriere della Sera), resulting in an overall sample of 446 newspaper articles. A computer-aided content analysis allowed the detection of five different thematic domains (clusters), respectively focused on: Medical care (7.47%), Family support (37.03%), Science and religion debate (27%), Social exclusion (17.6%) and Healthcare policies (10.9%). These thematic domains are conceived along two main latent dimensions (factors) which explain 72.47% of the data variance which respectively deal with: (1) Attitudes towards people with AIDS (care versus avoidance) and (2) Social mandate on AIDS (powerlessness versus control). The study results also reveal the potential evolution of representations of people with AIDS over time: from stigmatised subjects who represent a risk for the entire society within a climate of social control to people progressively symbolised as frail subjects that need to be taken care of. PMID:26923156

  7. Reducing AIDS-related stigma in developing countries: the importance of theory- and evidence-based interventions.

    PubMed

    Bos, Arjan E R; Schaalma, Herman P; Pryor, John B

    2008-08-01

    In many developing countries persons living with HIV and AIDS experience strong stigma and discrimination, and AIDS-related stigma has an enormous negative impact on their social relationships, access to resources, and psychological well being. Moreover, AIDS-related stigma hampers HIV-related health promotion, including voluntary HIV counselling and testing. In this article, we will argue that programs to reduce AIDS-related stigma are most likely to be effective if these programs are based upon thorough needs assessments, theory- and evidence-based intervention strategies and collaborative planning. A protocol for health promotion programs design is outlined. Furthermore, psychosocial correlates of AIDS-related stigma in developing countries, social-psychological theories that might be useful in designing intervention strategies to reduce stigmatisation and successful elements of previous interventions aimed at stigma reduction are discussed. It is concluded that psychological theory does provide guidelines for the development of stigma-reducing intervention programs, but that such programs can only be effective when based upon context-specific needs assessment and collaborative planning. PMID:18825583

  8. HIV/AIDS-Related Knowledge and Behaviors Among Most-at-Risk Populations in Vietnam

    PubMed Central

    Vian, Taryn; Semrau, Katherine; Hamer, Davidson H; Loan, Le Thi Thanh; Sabin, Lora L

    2012-01-01

    The U.S. President’s Emergency Plan for AIDS Relief (PEPFAR) has supported the Vietnamese Ministry of Health (MOH) in implementing behavior change strategies to slow the HIV epidemic. These programs target commercial sex workers (CSW), injection drug users (IDU), and men who have sex with men (MSM). Using data from a program evaluation to assess effectiveness of the PEPFAR intervention, we conducted a sub-analysis of HIV/AIDS knowledge, sexual behaviors, and injection drug risk behaviors among 2,199 Vietnamese respondents, including those reporting recent contact with an outreach worker and those who did not report contact. We found overall high levels of HIV/AIDS knowledge, low rates of needle sharing, and moderate to high rates of inconsistent condom use. Average knowledge scores of IDU were significantly higher than non-IDU for antiretroviral treatment knowledge, while MSM had significantly less knowledge of treatment compared to non-MSM. HIV/AIDS-related knowledge was not significantly associated with needle-sharing practices. Knowledge was modestly but significantly associated with more consistent use of condoms with primary and commercial sex partners, even after controlling for contact with an outreach worker. Contact with an outreach worker was also an independent predictor of more consistent condom use. Outreach programs appear to play a meaningful role in changing sexual behavior, though the effect of outreach on IDU risk behaviors was less clear. More research is needed to understand the relationship between outreach programs and skill development, motivation, and use of referral services by most-at-risk populations in Vietnam. PMID:23173025

  9. HIV/AIDS Related Stigma and Discrimination against PLWHA in Nigerian Population

    PubMed Central

    Bulgiba, Awang; Oche, Oche Mansur; Adekunjo, Felix Oluyemi

    2015-01-01

    Background HIV/AIDS remain a major public health concern in Nigeria. People living with HIV/AIDS (PLWHA) face not only personal medical problems but also social problems associated with the disease such as stigma and discriminatory attitudes. This study provides an insight into HIV/AIDS related stigma and discrimination against PLWHA in Nigeria. Methods The data for this study was extracted from the 2013 Nigeria Demographic and Health Survey conducted by the National Population Commission. All men and women aged 15–49 years, permanent residents and visitors of the households were eligible for the interview. Several questionnaires were used in the survey, some covering questions on HIV/AIDS. Results A total of 56 307 men and women aged 15–49 years participated in this national survey. About half of the population in Nigeria have HIV stigma. Younger persons, men, those without formal education and those within poor wealth index are more likely to have stigma towards PLWHA. In addition, married people are more likely to have stigma on PLWHA and are more likely to blame PLWHA for bringing the disease to the community. Also about half of the population discriminates against PLWHA. However, those with higher levels of education and those from higher wealth index seem to be more compassionate towards PLWHA. About 70% in the population are willing to care for relative with AIDS, even more so among those with higher level of education. Conclusion There is a high level of HIV stigma and discrimination against PLWHA in the Nigerian population. Education seems to play a major role in the society with respect to HIV stigma and discrimination against PLWHA. Educating the population with factual information on HIV/AIDS is needed to reduce stigma and discrimination towards PLWHA in the community. PMID:26658767

  10. Knowledge, attitude, and practice of HIV/AIDS-related stigma and discrimination reduction among nursing students in southwest Nigeria

    PubMed Central

    Farotimi, Adekunbi A; Nwozichi, Chinomso Ugochukwu; Ojediran, Tolulope D

    2015-01-01

    Background: One of the reported obstacles to the achievement of universal access to Human Immunodeficiency Virus (HIV) prevention, treatment, care, and support programs includes stigma and discrimination from health workers, particularly nurses. Since nursing students would become future practising nurses and are most likely exposed to caring for people living with HIV/AIDS (PL WHA) during their training, it is of great importance to assess the knowledge, attitude, and practice of student nurses toward the reduction of HIV/AIDS-related stigma and discrimination. Materials and Methods: A descriptive survey research design was used. A total of 150 nursing students were selected using the simple random sampling technique of fish bowl method with replacement. Data were obtained using a self-administered (33-item) validated questionnaire to assess the knowledge, attitude, and practice of student nurses with regard to HIV/AIDS-related stigma and discrimination reduction strategies. Reliability of the tool was tested using Cronbach alpha (R) yielding a reliability value of 0.72. Data collected were analyzed with descriptive statistics of frequencies and percentages. Results: Majority (76.0%) of the respondents were females and 82.7% were married. Respondents were found to have high knowledge (94.0%) of strategies for reducing HIV/AIDS-related stigma and discrimination. Also, 64% had moderate discriminatory attitude, 74% engaged in low discriminatory practice, while 26% engaged in high discriminatory practice. Conclusions: Student nurses had adequate knowledge about strategies for reducing HIV/AIDS-related stigma and discrimination; negative discriminatory attitude toward PLWHA and some form of discriminatory practices exist in participants’ training schools. It is, therefore, recommended that an educational package on reduction of HIV/AIDS-related stigma and discrimination be developed and implemented for the participants. PMID:26793257

  11. Genetically Modified Peripheral Blood Stem Cell Transplant in Treating Patients With HIV-Associated Non-Hodgkin or Hodgkin Lymphoma

    ClinicalTrials.gov

    2015-05-06

    Adult Nasal Type Extranodal NK/T-cell Lymphoma; AIDS-related Diffuse Large Cell Lymphoma; AIDS-related Diffuse Mixed Cell Lymphoma; AIDS-related Diffuse Small Cleaved Cell Lymphoma; AIDS-related Immunoblastic Large Cell Lymphoma; AIDS-related Lymphoblastic Lymphoma; AIDS-related Peripheral/Systemic Lymphoma; AIDS-related Small Noncleaved Cell Lymphoma; Anaplastic Large Cell Lymphoma; Angioimmunoblastic T-cell Lymphoma; Cutaneous B-cell Non-Hodgkin Lymphoma; Extranodal Marginal Zone B-cell Lymphoma of Mucosa-associated Lymphoid Tissue; Hepatosplenic T-cell Lymphoma; HIV-associated Hodgkin Lymphoma; Intraocular Lymphoma; Nodal Marginal Zone B-cell Lymphoma; Noncutaneous Extranodal Lymphoma; Peripheral T-cell Lymphoma; Recurrent Adult Burkitt Lymphoma; Recurrent Adult Diffuse Large Cell Lymphoma; Recurrent Adult Diffuse Mixed Cell Lymphoma; Recurrent Adult Diffuse Small Cleaved Cell Lymphoma; Recurrent Adult Grade III Lymphomatoid Granulomatosis; Recurrent Adult Hodgkin Lymphoma; Recurrent Adult Immunoblastic Large Cell Lymphoma; Recurrent Adult Lymphoblastic Lymphoma; Recurrent Adult T-cell Leukemia/Lymphoma; Recurrent Cutaneous T-cell Non-Hodgkin Lymphoma; Recurrent Grade 1 Follicular Lymphoma; Recurrent Grade 2 Follicular Lymphoma; Recurrent Grade 3 Follicular Lymphoma; Recurrent Mantle Cell Lymphoma; Recurrent Marginal Zone Lymphoma; Recurrent Mycosis Fungoides/Sezary Syndrome; Recurrent Small Lymphocytic Lymphoma; Refractory Hairy Cell Leukemia; Small Intestine Lymphoma; Splenic Marginal Zone Lymphoma; Stage I AIDS-related Lymphoma; Stage II AIDS-related Lymphoma; Stage III AIDS-related Lymphoma; Stage IV AIDS-related Lymphoma; T-cell Large Granular Lymphocyte Leukemia; Testicular Lymphoma; Waldenström Macroglobulinemia

  12. Romidepsin in Treating Patients With Lymphoma, Chronic Lymphocytic Leukemia, or Solid Tumors With Liver Dysfunction

    ClinicalTrials.gov

    2016-09-09

    Adult Mixed Glioma; Adult Pineal Gland Astrocytoma; Adult Solid Neoplasm; AIDS Related Immunoblastic Lymphoma; AIDS-Related Burkitt Lymphoma; AIDS-Related Diffuse Large Cell Lymphoma; AIDS-Related Diffuse Mixed Cell Lymphoma; AIDS-Related Diffuse Small Cleaved Cell Lymphoma; AIDS-Related Hodgkin Lymphoma; AIDS-Related Lymphoblastic Lymphoma; AIDS-Related Lymphoma; AIDS-Related Primary Central Nervous System Lymphoma; Glioma; Lymphoma; Recurrent Adult Brain Neoplasm; Recurrent Adult Soft Tissue Sarcoma; Recurrent Bladder Carcinoma; Recurrent Breast Carcinoma; Recurrent Chronic Lymphocytic Leukemia; Recurrent Colorectal Carcinoma; Recurrent Cutaneous T-Cell Non-Hodgkin Lymphoma; Recurrent Head and Neck Carcinoma; Recurrent Lung Carcinoma; Recurrent Mature T- and NK-Cell Non-Hodgkin Lymphoma; Recurrent Melanoma; Recurrent Pancreatic Carcinoma; Recurrent Prostate Carcinoma; Recurrent Renal Cell Carcinoma; Recurrent Thyroid Gland Carcinoma; Refractory Chronic Lymphocytic Leukemia; Refractory Cutaneous T-Cell Non-Hodgkin Lymphoma; Refractory Mature T-Cell and NK-Cell Non-Hodgkin Lymphoma

  13. Creating social spaces to tackle AIDS-related stigma: reviewing the role of church groups in Sub-Saharan Africa.

    PubMed

    Campbell, C; Skovdal, M; Gibbs, A

    2011-08-01

    An expanding body of literature explores the role of African church groups in facilitating or hindering the support of people living with AIDS and challenging or contributing to HIV/AIDS-related stigma. Treating church groups as social spaces in which HIV/AIDS-related stigma may potentially be challenged, we systematically review this literature, identifying five themes that highlight the complex and contradictory role of the church as a potential agent of health-enhancing social change. In many ways the church perpetuates HIV/AIDS-related stigma through (i) moralistic attitudes and (ii) its reinforcement of conservative gender ideologies. However some churches have managed move towards action that makes a more positive contribution to HIV/AIDS management through (iii) promoting various forms of social control for HIV prevention, (iv) contributing to the care and support of the AIDS-affected and (v) providing social spaces for challenging stigmatising ideas and practices. We conclude that church groups, including church leadership, can play a key role in facilitating or hindering the creation of supportive social spaces to challenge stigma. Much work remains to be done in developing deeper understandings of the multi-layered factors that enable some churches, but not others, to respond effectively to HIV/AIDS. PMID:20668927

  14. Creating Social Spaces to Tackle AIDS-Related Stigma: Reviewing the Role of Church Groups in Sub-Saharan Africa

    PubMed Central

    Skovdal, M.; Gibbs, A.

    2012-01-01

    An expanding body of literature explores the role of African church groups in facilitating or hindering the support of people living with AIDS and challenging or contributing to HIV/AIDS-related stigma. Treating church groups as social spaces in which HIV/AIDS-related stigma may potentially be challenged, we systematically review this literature, identifying five themes that highlight the complex and contradictory role of the church as a potential agent of health-enhancing social change. In many ways the church perpetuates HIV/AIDS-related stigma through (i) moralistic attitudes and (ii) its reinforcement of conservative gender ideologies. However some churches have managed move towards action that makes a more positive contribution to HIV/AIDS management through (iii) promoting various forms of social control for HIV prevention, (iv) contributing to the care and support of the AIDS-affected and (v) providing social spaces for challenging stigmatising ideas and practices. We conclude that church groups, including church leadership, can play a key role in facilitating or hindering the creation of supportive social spaces to challenge stigma. Much work remains to be done in developing deeper understandings of the multi-layered factors that enable some churches, but not others, to respond effectively to HIV/AIDS. PMID:20668927

  15. Belief in AIDS-Related Conspiracy Theories and Mistrust in the Government: Relationship With HIV Testing Among At-Risk Older Adults

    PubMed Central

    Ford, Chandra L.

    2013-01-01

    Purpose: One in 4 persons living with HIV/AIDS is an older adult (age 50 or older); unfortunately, older adults are disproportionately diagnosed in late stages of HIV disease. Psychological barriers, including belief in AIDS-related conspiracy theories (e.g., HIV was created to eliminate certain groups) and mistrust in the government, may influence whether adults undergo HIV testing. We examined relationships between these factors and recent HIV testing among at-risk, older adults. Design and Methods: This was a cross-sectional study among older adults enrolled in a large venue–based study. None had a previous diagnosis of HIV/AIDS; all were seeking care at venues with high HIV prevalence. We used multiple logistic regression to estimate the associations between self-reported belief in AIDS-related conspiracy theories, mistrust in the government, and HIV testing performed within the past 12 months. Results: Among the 226 participants, 30% reported belief in AIDS conspiracy theories, 72% reported government mistrust, and 45% reported not undergoing HIV testing within the past 12 months. Belief in conspiracy theories was positively associated with recent HIV testing (adjusted odds ratio [OR] = 1.94, 95% confidence interval [CI] = 1.05–3.60), whereas mistrust in the government was negatively associated with testing (OR = 0.43, 95% CI = 0.26–0.73). Implications: Psychological barriers are prevalent among at-risk older adults seeking services at venues with high HIV prevalences and may influence HIV testing. Identifying particular sources of misinformation and mistrust would appear useful for appropriate targeting of HIV testing strategies. PMID:23362210

  16. With and without: the bereavement experiences of gay men who have lost a partner to non-AIDS-related causes.

    PubMed

    Hornjatkevyc, Nina L

    2011-10-01

    This study gives voice to the experiences of gay men who have lost a partner to non-AIDS-related causes, a subject that has received little attention in the psychological literature. Interviews were conducted with 8 gay men. An analysis informed by hermeneutic phenomenology generated themes and contexualized meanings regarding the participants' diverse experiences. The themes identified areas of similarity and difference between the bereavement of these participants from those who have participated in general bereavement studies and from those who have lost a partner to AIDS. Implications for counseling practice and further research are discussed. PMID:24501836

  17. Recruiting Chinese American adolescents to HIV/AIDS-related research: a lesson learned from a cross-sectional study.

    PubMed

    Lee, Yi-Hui; Salman, Ali; Wang, Fan

    2012-02-01

    The purpose of this article was to report identified barriers and challenges experienced in the recruiting process of Chinese American adolescents to a cross-sectional HIV/AIDS-related study. Snowball sampling method was used to recruit Chinese American adolescents from Chinese American communities in a U.S. Midwestern state. Barriers and challenges to recruitment were reviewed and analyzed from Chinese cultural perspectives in the hope of aiding researchers and health care providers understand and facilitate future recruitment of Chinese Americans for HIV/AIDS prevention studies. Barriers to recruitment were found related to the taboo topic of sexual issues in Chinese culture, unawareness and denial of HIV/AIDS risks, authoritarian parenting style in Chinese culture, and the required active consents. Facilitating factors of recruiting Chinese American adolescents to future HIV/AIDS prevention research or intervention programs are discussed. Information provided in this article may increase nurses' awareness of various barriers that they might encounter when they conduct research or address HIV/AIDS-related topics of Chinese American adolescents. PMID:20974090

  18. Ethnobotanical Study of Plants Used in the Management of HIV/AIDS-Related Diseases in Livingstone, Southern Province, Zambia

    PubMed Central

    Chinsembu, Kazhila C.

    2016-01-01

    Faced with critical shortages of staff, long queues, and stigma at public health facilities in Livingstone, Zambia, persons who suffer from HIV/AIDS-related diseases use medicinal plants to manage skin infections, diarrhoea, sexually transmitted infections, tuberculosis, cough, malaria, and oral infections. In all, 94 medicinal plant species were used to manage HIV/AIDS-related diseases. Most remedies are prepared from plants of various families such as Combretaceae, Euphorbiaceae, Fabaceae, and Lamiaceae. More than two-thirds of the plants (mostly leaves and roots) are utilized to treat two or more diseases related to HIV infection. Eighteen plants, namely, Achyranthes aspera L., Lannea discolor (Sond.) Engl., Hyphaene petersiana Klotzsch ex Mart., Asparagus racemosus Willd., Capparis tomentosa Lam., Cleome hirta Oliv., Garcinia livingstonei T. Anderson, Euclea divinorum Hiern, Bridelia cathartica G. Bertol., Acacia nilotica Delile, Piliostigma thonningii (Schumach.) Milne-Redh., Dichrostachys cinerea (L.) Wight and Arn., Abrus precatorius L., Hoslundia opposita Vahl., Clerodendrum capitatum (Willd.) Schumach., Ficus sycomorus L., Ximenia americana L., and Ziziphus mucronata Willd., were used to treat four or more disease conditions. About 31% of the plants in this study were administered as monotherapies. Multiuse medicinal plants may contain broad-spectrum antimicrobial agents. However, since widely used plants easily succumb to the threats of overharvesting, they need special protocols and guidelines for their genetic conservation. There is still need to confirm the antimicrobial efficacies, pharmacological parameters, cytotoxicity, and active chemical ingredients of the discovered plants. PMID:27069489

  19. Ethnobotanical Study of Plants Used in the Management of HIV/AIDS-Related Diseases in Livingstone, Southern Province, Zambia.

    PubMed

    Chinsembu, Kazhila C

    2016-01-01

    Faced with critical shortages of staff, long queues, and stigma at public health facilities in Livingstone, Zambia, persons who suffer from HIV/AIDS-related diseases use medicinal plants to manage skin infections, diarrhoea, sexually transmitted infections, tuberculosis, cough, malaria, and oral infections. In all, 94 medicinal plant species were used to manage HIV/AIDS-related diseases. Most remedies are prepared from plants of various families such as Combretaceae, Euphorbiaceae, Fabaceae, and Lamiaceae. More than two-thirds of the plants (mostly leaves and roots) are utilized to treat two or more diseases related to HIV infection. Eighteen plants, namely, Achyranthes aspera L., Lannea discolor (Sond.) Engl., Hyphaene petersiana Klotzsch ex Mart., Asparagus racemosus Willd., Capparis tomentosa Lam., Cleome hirta Oliv., Garcinia livingstonei T. Anderson, Euclea divinorum Hiern, Bridelia cathartica G. Bertol., Acacia nilotica Delile, Piliostigma thonningii (Schumach.) Milne-Redh., Dichrostachys cinerea (L.) Wight and Arn., Abrus precatorius L., Hoslundia opposita Vahl., Clerodendrum capitatum (Willd.) Schumach., Ficus sycomorus L., Ximenia americana L., and Ziziphus mucronata Willd., were used to treat four or more disease conditions. About 31% of the plants in this study were administered as monotherapies. Multiuse medicinal plants may contain broad-spectrum antimicrobial agents. However, since widely used plants easily succumb to the threats of overharvesting, they need special protocols and guidelines for their genetic conservation. There is still need to confirm the antimicrobial efficacies, pharmacological parameters, cytotoxicity, and active chemical ingredients of the discovered plants. PMID:27069489

  20. AIDS-Related Stigma and Mental Disorders among People Living with HIV: A Cross-Sectional Study in Cambodia

    PubMed Central

    Yi, Siyan; Chhoun, Pheak; Suong, Samedy; Thin, Kouland; Brody, Carinne; Tuot, Sovannary

    2015-01-01

    Background AIDS-related stigma and mental disorders are the most common conditions in people living with HIV (PLHIV). We therefore conducted this study to examine the association of AIDS-related stigma and discrimination with mental disorders among PLHIV in Cambodia. Methods A two-stage cluster sampling method was used to select 1,003 adult PLHIV from six provinces. The People Living with HIV Stigma Index was used to measure stigma and discrimination, and a short version of general health questionnaire (GHQ-12) was used to measure mental disorders. Multivariate logistic regression analysis was conducted. Results The reported experiences of discrimination in communities in the past 12 months ranged from 0.8% for reports of being denied health services to 42.3% for being aware of being gossiped about. Internal stigma was also common ranging from 2.8% for avoiding going to a local clinic and/or hospital to 59.6% for deciding not to have (more) children. The proportions of PLHIV who reported fear of stigma and discrimination ranged from 13.9% for fear of being physically assaulted to 34.5% for fear of being gossiped about. The mean score of GHQ-12 was 3.2 (SD = 2.4). After controlling for several potential confounders, higher levels of mental disorders (GHQ-12≥ 4) remained significantly associated with higher levels of experiences of stigma and discrimination in family and communities (AOR = 1.9, 95% CI = 1.4–2.6), higher levels of internal stigma (AOR = 1.7, 95% CI = 1.2–2.3), and higher levels of fear of stigma and discrimination in family and communities (AOR = 1.5, 95% CI = 1.1–2.2). Conclusions AIDS-related stigma and discrimination among PLHIV in Cambodia are common and may have potential impacts on their mental health conditions. These findings indicate a need for community-based interventions to reduce stigma and discrimination in the general public and to help PLHIV to cope with this situation. PMID:25806534

  1. Amphotericin B lipid complex available for AIDS related cryptococcal meningitis. South Africa.

    PubMed

    1993-10-11

    Amphotericin B is generally considered to be the standard treatment against candidiasis, cryptococcal meningitis, and aspergillosis. The potential side effects of kidney toxicity and anemia, however, limit its use. Amphotericin B has therefore been incorporated into a lipid complex and clinical results thus far suggest that this ensemble may significantly reduce the risk of toxicity while maintaining or increasing drug efficacy. This modified version of amphotericin B (ABLC) is available on a compassionate use basis in the US and Europe for patients with life-threatening systemic fungal infections for whom currently marketed drugs are ineffective or too toxic. 250 patients have thus far been treated with ABLC under the compassionate use program; several hundred more have received it in controlled clinical trials; and additional large US phase 3 trials are being planned. The Liposome Company, Inc., of Princeton, New Jersey, has initiated named patient distribution of ABLC in the Republic of South Africa. 2 patients with cryptococcal meningitis have thus far received it. Cryptococcal meningitis is a type of fungal infection occurring in up to 10% of patients with AIDS; 20% of patients die within 30 days of diagnosis. The chairman and CEO of Liposome argues that getting the drug to AIDS patients in South Africa will help the company accumulate data quickly on the drug's efficacy and safety. The company is also working upon an application to get ABLC approved for use in Europe. PMID:12345310

  2. Specificity of anti-lymphocyte antibodies in sera from patients with AIDS-related complex (ARC) and healthy homosexuals.

    PubMed Central

    Warren, R Q; Johnson, E A; Donnelly, R P; Lavia, M F; Tsang, K Y

    1988-01-01

    The presence and specificity of anti-lymphocyte antibodies (ALA) was investigated in sera from male homosexuals with AIDS-Related Complex (ARC) as well as healthy homosexuals. Individuals in the healthy homosexual group had no detectable antibodies to human immunodeficiency virus (HIV). Antibodies reactive with normal peripheral blood mononuclear cells were detected by Western blot analysis in sera from both groups of homosexuals. Of those individuals whose sera contained ALA, 71% of ARC patients and 83% of healthy homosexuals had antibodies recognizing a 73 kilodalton (kD) molecule. ALA present in ARC sera reacted with CD3+, CD4+ and CD8+ lymphocytes while little reactivity with B cells was observed. Our results indicate that ALA appear in homosexuals prior to HIV infection and are reactive primarily with T lymphocytes. A 73 kD structure associated with the T cell membrane is frequently the target for these antibodies. Images Fig. 1 Fig. 2 Fig. 3 PMID:3052941

  3. PHASE II AIDS MALIGNANCY CONSORTIUM TRIAL OF TOPICAL HALOFUGINONE IN AIDS-RELATED KAPOSI’S SARCOMA

    PubMed Central

    Koon, Henry B.; Fingleton, Barbara; Lee, Jeannette Y.; Geyer, Julia T.; Cesarman, Ethel; Parise, Robert A.; Egorin, Merrill J.; Dezube, Bruce J.; Aboulafia, David; Krown, Susan E.

    2010-01-01

    Using a novel blinded intra-patient vehicle control design, we conducted a phase II study of topically-administered halofuginone, an angiogenesis inhibitor that inhibits collagen type-I and matrix metalloproteinases (MMPs), in patients with AIDS-related Kaposi’s sarcoma (KS). Serial KS biopsies assessed treatment effects on angiogenic factors and KSHV-LANA. We observed marked heterogeneity of KSHV-LANA expression. Although the small number of subjects whose response could be evaluated precluded definitive assessment of halofuginone’s efficacy, we observed a significant decrease in type-I collagen only in halofuginone-treated lesions, but no effect on MMP-2. The trial design is applicable to future studies of topical agents. PMID:21068672

  4. Help-seeking for AIDS-related concerns: a comparison of gay men with various HIV diagnoses.

    PubMed

    Hays, R B; Catania, J A; McKusick, L; Coates, T J

    1990-10-01

    Examined help-seeking and psychological distress among four groups of gay men (30 AIDS-diagnosed, 107 HIV-seropositive, 149 HIV-seronegative, 244 untested) in the AIDS Behavioral Research Project, a longitudinal survey of San Francisco gay men. The men reported high levels of anxiety, depression, and help-seeking from their social networks. AIDS-diagnosed and HIV-positives reported the most AIDS worry and were the most likely to seek help. High percentages of AIDS-diagnosed men sought help from all sources (peers, professionals, family), whereas nondiagnosed men were more likely to seek help from peers. Regardless of the men's HIV status, peers were perceived to be the most helpful source. Family members were less likely sought and perceived as least helpful. The strengths and limitations of peers as social support providers for AIDS-related concerns are discussed, including implications for the design of community programs to enhance the abilities of peer helpers. PMID:2075900

  5. Professionalisation and social attitudes: a protocol for measuring changes in HIV/AIDS-related stigma among healthcare students

    PubMed Central

    Ahmadi, Keivan; Reidpath, Daniel D; Allotey, Pascale; Hassali, Mohamed Azmi Ahmad

    2013-01-01

    Introduction HIV/AIDS-related stigma affects the access and utilisation of health services. Although HIV/AIDS-related stigma in the health services has been studied, little work has attended to the relationship between professional development and stigmatising attitudes. Hence, in this study, we will extend earlier research by examining the relationship between the stage of professional development and the kinds of stigmatising attitudes held about people living with HIV/AIDS. Methods and analysis A serial cross-sectional design will be combined with a two-point in time longitudinal design to measure the levels of stigma among healthcare students from each year of undergraduate and graduate courses in Malaysia and Australia. In the absence of suitable measures, we will carry out a sequential mixed methods design to develop such a tool. The questionnaire data will be analysed using mixed effects linear models to manage the repeated measures. Ethics and dissemination We have received ethical approval from the Monash MBBS executive committee as well as the Monash University Human Research Ethics Committee. We will keep the data in a locked filing cabinet in the Monash University (Sunway campus) premises for 5 years, after which the information will be shredded and disposed of in secure bins, and digital recordings will be erased in accordance with Monash University's regulations. Only the principal investigator and the researcher will have access to the filing cabinet. We aim to present and publish the results of this study in national and international conferences and peer-reviewed journals, respectively. PMID:23793653

  6. Altered natural history of AIDS-related opportunistic infections in the era of potent combination antiretroviral therapy.

    PubMed

    Jacobson, M A; French, M

    1998-01-01

    Since potent HIV protease inhibitor drugs became widely available in early 1996, many HIV clinical specialists have noted a marked decrease in the occurrence of AIDS-related opportunistic infections, and some specialists have reported unusual clinical presentations and manifestations of previously common opportunistic infections. In this article, we will review (1) the available data regarding recent trends in AIDS-related opportunistic infections incidence and manifestations, (2) clinical and immunologic evidence that potent combination antiretroviral therapy can alter the natural history of these opportunistic infections, and (3) the implications of these findings for current patient management practice and future clinical and immunologic research. As a preface to this review, however, it is important to acknowledge that any evaluation of the potential benefit of potent combination antiretroviral therapy in reducing the risk of serious opportunistic infections can be confounded by the concomitant use of prophylactic antimicrobial agents co-administered to prevent specific opportunistic infections. For example, it is standard clinical practice to administer trimethoprim-sulfamethoxazole (or another agent if trimethoprim-sulfamethoxazole cannot be tolerated) to patients with an absolute CD4 lymphocyte count < 200 cells/microliters, unexplained chronic fever or a history of oropharyngeal candidiasis. Similarly, specific antimicrobial prophylaxis to prevent disseminated Mycobacterium avium complex (MAC) infection in patients with absolute CD4 counts < 50 cells/microliters is also a widely recommended guideline. Although the relative efficacies of specific antimicrobial prophylaxis regimens in preventing the most common life- and sight-threatening opportunistic infectious complications of AIDS [Pneumocystis carinii pneumonia (PCP), disseminated MAC infection, and cytomegalovirus (CMV) retinitis] are now well established, these relative efficacies were established in

  7. HIV/AIDS-related stigmatizing and discriminatory attitudes and recent HIV testing among men who have sex with men in Beijing.

    PubMed

    Li, Xuefeng; Lu, Hongyan; Ma, Xiaoyan; Sun, Yanming; He, Xiong; Li, Chunmei; Raymond, H F; McFarland, Willi; Pan, Stephen W; Shao, Yiming; Vermund, Sten H; Xiao, Yan; Ruan, Yuhua; Jia, Yujiang

    2012-04-01

    This study assessed the correlates of recent HIV testing and HIV/AIDS-related stigmatizing and discriminatory attitudes among men who have sex with men (MSM) in Beijing, China. A cross-sectional study probed demographics, sexual and drug use behaviors, HIV testing, and prevention services. Of 500 participants, 39.3% recently received a test for HIV. Recent testing was independently associated with expressing lower levels of HIV/AIDS-related stigmatizing and discriminatory attitudes, more male sex partners, no female sexual partners and knowing HIV status of their last male partner. Expressing lower levels of HIV/AIDS-related stigmatizing and discriminatory attitudes was independently associated with recent testing, younger age, and knowing HIV status of their last male partner. This study revealed that HIV/AIDS-related stigmatizing and discriminatory attitudes were common and inversely associated with recent HIV testing. Low levels of testing highlighted the urgent needs to reduce HIV/AIDS-related stigma and discrimination and expand HIV testing among MSM in Beijing. PMID:22350831

  8. AIDS-related myopathy.

    PubMed

    Sheikh, Rafiq A.; Yasmeen, Shagufta; Munn, Robert; Ruebner, Boris H.; Ellis, William G.

    1999-09-01

    Infection with the human immunodeficiency virus (HIV) is often associated with the acquired immunodeficiency syndrome (AIDS), and wasting is one of the defining clinical features of AIDS. Muscular weakness due to myopathy may develop at any stage of HIV infection. We report two illustrative cases of HIV-associated myopathies. One was due to inflammatory myosits most likely directly related to the HIV infection, and the other was most likely the result of mitochondrial damage due to zidovudine, a nucleoside analogue commonly used in treating HIV infection. Biopsies from both patients showed alterations of myofiber structures, of varying severity, culminating in necrosis, lipid droplets, and lymphoplasmocytic inflammatory response. The zidovudine-treated patient also showed distinctive mitochondrial changes, predominantly enlargement, variation in shape and size, and disorganization of the cristae. These two types of HIV-associated inflammatory myopathies are reviewed, along with other HIV-associated myopathies, including HIV wasting syndrome, nemaline rod myopathy, pyomyositis, rhabdomyolysis, cardiomyopathy, and other miscellaneous myopathies associated with HIV infection. PMID:11810429

  9. HIV/AIDS - Related Knowledge, Attitudes, and Sexual Practices among Migrant Wives in Rural Anhui Province, China

    PubMed Central

    Zou, Huachun; Dai, Xin; Meng, Xiaojun; Wang, Huadong; Jiang, Chao; Wang, Yanchun; Zhang, Lin; Gao, Yongqing; Tang, Song; Xu, Tan; Sun, Wenjie; Wen, Yufeng

    2015-01-01

    Background Migrant wives have been increasing in some poor rural regions of China and they may bridge HIV transmission across regions. This study aimed to assess HIV/AIDS-related knowledge, attitudes and sexual practices among this population in rural Anhui Province, China. Methods A cross-sectional survey was conducted with questionnaire of HIV/AIDS-related knowledge, attitudes, and sexual practices between June 2011 and May 2012. A total of 730 migrant wives and 207 local women were enrolled in this study. Unpaired T-test, Chi-square was utilized to compare the difference of HIV/AIDS knowledge, attitudes and sexual practices between migrant wives and local women. Results Around 80% of the migrant wives were from Yunnan, Guizhou, or Sichuan Provinces. The main sources of HIV/AIDS information were TV/radio, posters, and newspapers/periodicals. HIV/AIDS knowledge level among migrant wives was significantly lower than that among local women (e.g. 47.1% vs 57.0% (p<0.001) answered “Yes” for the question “Can an apparently healthy person be HIV-infected?”), and stigma and prejudice towards HIV/AIDS among migrant wives were more common than those among local women (e.g. 73.2% vs 65.7% (p=0.006) answered “No” for the question “If a shopkeeper or food seller had the HIV, would you buy food from them?”). Compared to local women, migrant wives were more likely to have ever had sex during menstruation (6.8% vs 3.4%, p=0.065) and extramarital sex (17.5% vs 10.1%, p=0.01), and were less likely to consistently use condoms with their husbands (45.8% vs 57.5%, p<0.001) or extramarital sex partners (48.8% vs 58.95, p<0.001). Conclusions Migrant wives in rural China had a low HIV/AIDS knowledge level and high prevalence of stigma and prejudice and risky sexual behaviors. Local HIV/AIDS prevention programs should target this neglected population. PMID:25844269

  10. Toxoplasma gondii Infection in Kyrgyzstan: Seroprevalence, Risk Factor Analysis, and Estimate of Congenital and AIDS-Related Toxoplasmosis

    PubMed Central

    Bodosheva, Aigerim; Kuttubaev, Omurbek; Hehl, Adrian B.; Tanner, Isabelle; Ziadinov, Iskender; Torgerson, Paul R.; Deplazes, Peter

    2013-01-01

    Background HIV-prevalence, as well as incidence of zoonotic parasitic diseases like cystic echinococcosis, has increased in the Kyrgyz Republic due to fundamental socio-economic changes after the breakdown of the Soviet Union. The possible impact on morbidity and mortality caused by Toxoplasma gondii infection in congenital toxoplasmosis or as an opportunistic infection in the emerging AIDS pandemic has not been reported from Kyrgyzstan. Methodology/Principal Findings We screened 1,061 rural and 899 urban people to determine the seroprevalence of T. gondii infection in 2 representative but epidemiologically distinct populations in Kyrgyzstan. The rural population was from a typical agricultural district where sheep husbandry is a major occupation. The urban population was selected in collaboration with several diagnostic laboratories in Bishkek, the largest city in Kyrgyzstan. We designed a questionnaire that was used on all rural subjects so a risk-factor analysis could be undertaken. The samples from the urban population were anonymous and only data with regard to age and gender was available. Estimates of putative cases of congenital and AIDS-related toxoplasmosis in the whole country were made from the results of the serology. Specific antibodies (IgG) against Triton X-100 extracted antigens of T. gondii tachyzoites from in vitro cultures were determined by ELISA. Overall seroprevalence of infection with T. gondii in people living in rural vs. urban areas was 6.2% (95%CI: 4.8–7.8) (adjusted seroprevalence based on census figures 5.1%, 95% CI 3.9–6.5), and 19.0% (95%CI: 16.5–21.7) (adjusted 16.4%, 95% CI 14.1–19.3), respectively, without significant gender-specific differences. The seroprevalence increased with age. Independently low social status increased the risk of Toxoplasma seropositivity while increasing numbers of sheep owned decreased the risk of seropositivity. Water supply, consumption of unpasteurized milk products or undercooked meat, as

  11. HIV/AIDS-related knowledge and behaviors among rural married migrant women in Shandong Province, China: a comparison study.

    PubMed

    Song, Yapei; Kang, Dianmin; Wang, Guoyong; Wei, Chongyi; Tao, Xiaorun; Huang, Tao; Qian, Yuesheng; Zhu, Tiwen; Yang, Shan; Yu, Shaoqi; Wang, Hong; Ma, Wei

    2015-02-01

    Migrant women in China are disproportionately affected by HIV/AIDS. This study described HIV/AIDS-related knowledge and behaviors among married migrant women in Shandong province in comparison to non-migrant local women and identified factors associated with HIV testing history and extramarital sex among married migrant women. A probability-based sample of 1,076 migrant and 1,195 local women were included in the analyses. Compared to local women, married migrant women had lower levels of HIV/AIDS knowledge and were more likely to have had premarital sex, extramarital sex, history of sexually transmitted diseases, and drug use. Less than a quarter of migrant women used condoms consistently in extramarital sex. Only 31.0 % of married migrant women had ever tested for HIV, and the rate of premarital HIV testing was very low. Multivariable analysis showed that married migrant women with a history of extramarital sex were more likely to be from Yunnan province, be living in Yantai city, be in their first marriage, have lower family income, have poor relationship with spouses, use drug, have a history of sexually transmitted diseases, and have lower social support. Our findings provide further evidence that married migrant women are at higher risk for HIV infection and that targeted interventions need to be developed for this population. PMID:25323941

  12. Longitudinal Effects of Coping on Outcome in a Randomized Controlled Trial of a Group Intervention for HIV-Positive Adults with AIDS-Related Bereavement

    ERIC Educational Resources Information Center

    Hansen, Nathan B.; Tarakeshwar, Nalini; Ghebremichael, Musie; Zhang, Heping; Kochman, Arlene; Sikkema, Kathleen J.

    2006-01-01

    This study examined the longitudinal effects of coping on outcome one year following completion of a randomized, controlled trial of a group coping intervention for AIDS-related bereavement. Bereaved HIV-positive participants (N = 267) were administered measures of grief, psychiatric distress, quality of life, and coping at baseline,…

  13. With and With"out": The Bereavement Experiences of Gay Men Who Have Lost a Partner to Non-AIDS-Related Causes

    ERIC Educational Resources Information Center

    Hornjatkevyc, Nina L.; Alderson, Kevin G.

    2011-01-01

    This study gives voice to the experiences of gay men who have lost a partner to non-AIDS-related causes, a subject that has received little attention in the psychological literature. Interviews were conducted with 8 gay men. An analysis informed by hermeneutic phenomenology generated themes and contextualized meanings regarding the participants'…

  14. The Unfinished Nature of Rights-Informed HIV- and AIDS-Related Education: An Analysis of Three School-Based Initiatives

    ERIC Educational Resources Information Center

    Miedema, Esther; Maxwell, Claire; Aggleton, Peter

    2015-01-01

    Over the past 25 years, there has been growing investment in concepts of rights in the areas of HIV prevention, care and treatment, including HIV- and AIDS-related education delivered in schools. Despite this increasing commitment to the notion of rights, few efforts appear to have been made to understand the varying conceptions of rights that…

  15. Autograft HIV-DNA Load Predicts HIV-1 Peripheral Reservoir After Stem Cell Transplantation for AIDS-Related Lymphoma Patients

    PubMed Central

    Bortolin, Maria Teresa; Pratesi, Chiara; Tedeschi, Rosamaria; Basaglia, Giancarlo; Abbruzzese, Luciano; Mazzucato, Mario; Spina, Michele; Vaccher, Emanuela; Tirelli, Umberto; Rupolo, Maurizio; Michieli, Mariagrazia; Di Mascio, Michele; De Paoli, Paolo

    2015-01-01

    Abstract Autologous stem cell transplantation (ASCT) is a widely used procedure for AIDS-related lymphomas, and it represents an opportunity to evaluate strategies curing HIV-1 infection. The association of autograft HIV-DNA load with peripheral blood HIV-1 reservoir before ASCT and its contribution in predicting HIV-1 reservoir size and stability during combination antiretroviral therapy (cART) after transplantation are unknown. Aiming to obtain information suggesting new functional cure strategies by ASCT, we retrospectively evaluated HIV-DNA load in autograft and in peripheral blood before and after transplantation in 13 cART-treated HIV-1 relapse/refractoring lymphoma patients. Among them seven discontinued cART after autograft infusion. HIV-DNA was evaluated by a sensitive quantitative real-time polymerase chain reaction (PCR). After debulking chemotherapy/mobilization, the autograft HIV-1 reservoir was higher than and not associated with the peripheral HIV-1 reservoir at baseline [median 215 HIV-DNA copies/106 autograft mononuclear cells, range 13–706 vs. 82 HIV-DNA copies/106 peripheral blood mononuclear cells (PBMCs), range 13–479, p=0.03]. After high dose chemotherapy and autograft infusion, HIV-DNA levels reached a plateau between month 6 and 12 of follow-up. No association was found between peripheral HIV-DNA levels at baseline and after infusion in both cART interrupting and not interrupting patients. Only in the last subgroup, a stable significant linear association between autograft and peripheral blood HIV-1 reservoir emerged from month 1 (R2=0.84, p=0.01) to month 12 follow-up (R2=0.99, p=0.0005). In summary, autograft HIV-1 reservoir size could be influenced by the mobilization phase and predicts posttransplant peripheral HIV-1 reservoir size in patients on continuous cART. These findings could promote new research on strategies reducing the HIV-1 reservoir by using the ASCT procedure. PMID:25581618

  16. Risk factors for HIV infection in male sexual contacts of men with AIDS or an AIDS-related condition.

    PubMed

    Coates, R A; Calzavara, L M; Read, S E; Fanning, M M; Shepherd, F A; Klein, M H; Johnson, J K; Soskolne, C L

    1988-10-01

    A total of 246 healthy male sexual contacts of men with either acquired immunodeficiency syndrome (AIDS) or an AIDS-related condition were recruited into a prospective study in Toronto, Canada between July 1984 and July 1985. At induction, data were collected on the sexual relationship between the contact and his primary case, sexual activities with other men, history of sexually transmitted diseases and other diseases, and use of recreational drugs. At recruitment, 144 sexual contacts had antibodies to human immunodeficiency virus (HIV); 102 of the contacts were seronegative at induction and at three months following recruitment. No association between HIV seropositivity and total number of sexual partners could be demonstrated. In univariate and multivariate analyses, receptive and insertive anal intercourse with the primary cases, and activities which either indicated or potentially caused anorectal mucosal injury (rectal douching, perianal bleeding, receipt of objects in ano, and receptive fisting) were strongly associated with HIV seropositivity. In the final multiple logistic regression model, two significant interaction effects were observed: the interaction between receptive anal intercourse and insertive anal intercourse and that between receptive anal intercourse and the anorectal mucosal injury index. These two interaction terms had negative regression coefficients which suggested that change in one sexual activity would not decrementally reduce risk of HIV infection without a comparable modification in the other activity. No association could be demonstrated between oral-genital and oral-anal sexual contact and odds ratios for these sexual activities declined to levels below 1.0 when adjusted for frequency of receptive anal intercourse. PMID:3421239

  17. Fulminant inflammatory leukoencephalopathy associated with HAART-induced immune restoration in AIDS-related progressive multifocal leukoencephalopathy.

    PubMed

    Vendrely, Aurélie; Bienvenu, Boris; Gasnault, Jacques; Thiebault, Jean Baptiste; Salmon, Dominique; Gray, Françoise

    2005-04-01

    HAART-induced immune restoration is beneficial for patients with AIDS-related progressive multifocal leukoencephalopathy (PML). However, in rare instances, an immune-reconstitution inflammatory syndrome (IRIS) may cause paradoxical clinical deterioration. We report the neuropathological study of an AIDS patient who presented with progressive cognitive deterioration; CD4(+) count was 117 and the HIV viral load >10(4); imaging showed non-enhancing lesions consistent with PML. Following initiation of HAART, CD4(+) was 300 and HIV viral load <10(3), but his neurological symptoms continued to deteriorate. Imaging revealed an increase in the size and number of lesions and enhancement of all the lesions. A stereotactic biopsy showed severe inflammatory and demyelinating lesions with marked infiltration by macrophages and T lymphocytes in the absence of a detectable infectious agent. Despite high doses of steroids, the patient died 3 months after admission. Autopsy showed two types of lesions: (1) active inflammatory PML changes with abundant JC virus, and intraparenchymal and perivascular infiltration by T lymphocytes, and (2) acute perivenous leukoencephalitis devoid of JC virus. Most lymphocytes were CD8(+) lymphocytes; CD4(+) lymphocytes were virtually absent. Two pathological reactions were associated with the paradoxical clinical deterioration related to dysregulation of the immune response characteristic of IRIS in PML: (1) an accentuation of JCV infection, and (2) a nonspecific acute perivenous leukoencephalitis. We suggest that both these types of lesions are due to an imbalance of CD8(+)/CD4(+) T cells, with massive infiltration of the cerebral parenchyma by CD8(+) cytotoxic T lymphocytes in the absence of sufficient CD4(+) response. Better understanding of the mechanisms of the IRIS may enable prevention or cure of this severe, sometimes fatal complication of HAART. PMID:15739098

  18. Autograft HIV-DNA load predicts HIV-1 peripheral reservoir after stem cell transplantation for AIDS-related lymphoma patients.

    PubMed

    Zanussi, Stefania; Bortolin, Maria Teresa; Pratesi, Chiara; Tedeschi, Rosamaria; Basaglia, Giancarlo; Abbruzzese, Luciano; Mazzucato, Mario; Spina, Michele; Vaccher, Emanuela; Tirelli, Umberto; Rupolo, Maurizio; Michieli, Mariagrazia; Di Mascio, Michele; De Paoli, Paolo

    2015-01-01

    Autologous stem cell transplantation (ASCT) is a widely used procedure for AIDS-related lymphomas, and it represents an opportunity to evaluate strategies curing HIV-1 infection. The association of autograft HIV-DNA load with peripheral blood HIV-1 reservoir before ASCT and its contribution in predicting HIV-1 reservoir size and stability during combination antiretroviral therapy (cART) after transplantation are unknown. Aiming to obtain information suggesting new functional cure strategies by ASCT, we retrospectively evaluated HIV-DNA load in autograft and in peripheral blood before and after transplantation in 13 cART-treated HIV-1 relapse/refractoring lymphoma patients. Among them seven discontinued cART after autograft infusion. HIV-DNA was evaluated by a sensitive quantitative real-time polymerase chain reaction (PCR). After debulking chemotherapy/mobilization, the autograft HIV-1 reservoir was higher than and not associated with the peripheral HIV-1 reservoir at baseline [median 215 HIV-DNA copies/10(6) autograft mononuclear cells, range 13-706 vs. 82 HIV-DNA copies/10(6) peripheral blood mononuclear cells (PBMCs), range 13-479, p = 0.03]. After high dose chemotherapy and autograft infusion, HIV-DNA levels reached a plateau between month 6 and 12 of follow-up. No association was found between peripheral HIV-DNA levels at baseline and after infusion in both cART interrupting and not interrupting patients. Only in the last subgroup, a stable significant linear association between autograft and peripheral blood HIV-1 reservoir emerged from month 1 (R(2) = 0.84, p = 0.01) to month 12 follow-up (R(2) = 0.99, p = 0.0005). In summary, autograft HIV-1 reservoir size could be influenced by the mobilization phase and predicts posttransplant peripheral HIV-1 reservoir size in patients on continuous cART. These findings could promote new research on strategies reducing the HIV-1 reservoir by using the ASCT procedure. PMID:25581618

  19. The influence of personality disorder indication, social support, and grief on alcohol and cocaine use among HIV-positive adults coping with AIDS-related bereavement.

    PubMed

    Hansen, Nathan B; Cavanaugh, Courtenay E; Vaughan, Ellen L; Connell, Christian M; Tate, David C; Sikkema, Kathleen J

    2009-04-01

    Substance use is prevalent among HIV-positive adults and linked to a number of adverse health consequences; however little is known about risk and protective factors that influence substance use among HIV-positive adults coping with AIDS-related bereavement. Using structural equation modeling (SEM), male gender, diagnostic indications of antisocial and borderline personality disorders (PD), and grief severity were tested as risk factors, and social support as a protective factor, for alcohol and cocaine use among a diverse sample of 268 HIV-positive adults enrolled in an intervention for AIDS-related bereavement. Results indicated that the hypothesized model fit the study data. Male gender, PD indication, and social support had direct effects on substance use. PD had significant indirect effects on both alcohol and cocaine use, mediated by social support, but not by grief. Finally, both PD and social support had significant, but opposite, effects on grief. Implications for intervention and prevention efforts are discussed. PMID:17846878

  20. A comparison of HIV/AIDS-related stigma in four countries: Negative attitudes and perceived acts of discrimination towards people living with HIV/AIDS☆

    PubMed Central

    Genberg, Becky L.; Hlavka, Zdenek; Konda, Kelika A.; Maman, Suzanne; Chariyalertsak, Suwat; Chingono, Alfred; Mbwambo, Jessie; Modiba, Precious; Van Rooyen, Heidi; Celentano, David D.

    2010-01-01

    HIV/AIDS-related stigma and discrimination have a substantial impact on people living with HIV/AIDS (PLHA). The objectives of this study were: (1) to determine the associations of two constructs of HIV/AIDS-related stigma and discrimination (negative attitudes towards PLHA and perceived acts of discrimination towards PLHA) with previous history of HIV testing, knowledge of antiretroviral therapies (ARVs) and communication regarding HIV/AIDS and (2) to compare these two constructs across the five research sites with respect to differing levels of HIV prevalence and ARV coverage, using data presented from the baseline survey of U.S. National Institute of Mental Health (NIMH) Project Accept, a four-country HIV prevention trial in Sub-Saharan Africa (Tanzania, Zimbabwe and South Africa) and northern Thailand. A household probability sample of 14,203 participants completed a survey including a scale measuring HIV/AIDS-related stigma and discrimination. Logistic regression models determined the associations between negative attitudes and perceived discrimination with individual history of HIV testing, knowledge of ARVs and communication regarding HIV/AIDS. Spearman's correlation coefficients determined the relationships between negative attitudes and perceived discrimination and HIV prevalence and ARV coverage at the site-level. Negative attitudes were related to never having tested for HIV, lacking knowledge of ARVs, and never having discussed HIV/AIDS. More negative attitudes were found in sites with the lowest HIV prevalence (i.e., Tanzania and Thailand) and more perceived discrimination against PLHA was found in sites with the lowest ARV coverage (i.e., Tanzania and Zimbabwe). Programs that promote widespread HIV testing and discussion of HIV/AIDS, as well as education regarding and universal access to ARVs, may reduce HIV/AIDS-related stigma and discrimination. PMID:19427086

  1. Validity and Reliability of Persian Version of HIV/AIDS Related Stigma Scale for People Living With HIV/AIDS in Iran

    PubMed Central

    Pourmarzi, Davoud; Khoramirad, Ashraf; Ahmari Tehran, Hoda; Abedini, Zahra

    2015-01-01

    Objective: To assess the perceived HIV/AIDS related stigma a comprehensive and well developed stigma instrument is necessary. This study aimed to assess validity and reliability of the Persian version of HIV/AIDS related stigma scale which was developed by Kang et al for people living with HIV/AIDS in Iran. Materials and methods: Thescale was forward translatedby two bilingual academic members then both translations were discussed by expert team. Back-translation was done by two other bilingual translators then we carried out discussion with both of them. To evaluate understandability the scale was administered to 10 Persons Living with HIV/AIDS (PLWHA). Final Persian version was administered to 80 PLWHA in Qom, Iran in 2014. Test–retest reliability was assessed in a sample of 20 PLWHA after a week by intra-class correlation coefficient (ICC). Results: Cronbach’s alpha coefficient for overall scale was 0.85. Also Cronbach’s alpha coefficients for the five subscales were as follows: social rejection (9 items, α = 0.84), negative self-worth (4 items, α = 0.70), perceived interpersonal insecurity (2 items, α = 0.57), financial insecurity (3 items, α = 0.70), discretionary disclosure (2 items, α = 0.83). Test–retest reliability was also approved with ICC = 0.78. Correlation between items and their hypothesized subscale is greater than 0.5. Correlation between an item and its own subscale was significantly higher than its correlation with other subscales. Conclusion: This study demonstrate that the Persian version of HIV/AIDS related stigma scale is valid and reliable to assess HIV/AIDS related stigma perceived by people living whit HIV/AIDS in Iran. PMID:27047562

  2. A comparison of HIV/AIDS-related stigma in four countries: negative attitudes and perceived acts of discrimination towards people living with HIV/AIDS.

    PubMed

    Genberg, Becky L; Hlavka, Zdenek; Konda, Kelika A; Maman, Suzanne; Chariyalertsak, Suwat; Chingono, Alfred; Mbwambo, Jessie; Modiba, Precious; Van Rooyen, Heidi; Celentano, David D

    2009-06-01

    HIV/AIDS-related stigma and discrimination have a substantial impact on people living with HIV/AIDS (PLHA). The objectives of this study were: (1) to determine the associations of two constructs of HIV/AIDS-related stigma and discrimination (negative attitudes towards PLHA and perceived acts of discrimination towards PLHA) with previous history of HIV testing, knowledge of antiretroviral therapies (ARVs) and communication regarding HIV/AIDS and (2) to compare these two constructs across the five research sites with respect to differing levels of HIV prevalence and ARV coverage, using data presented from the baseline survey of U.S. National Institute of Mental Health (NIMH) Project Accept, a four-country HIV prevention trial in Sub-Saharan Africa (Tanzania, Zimbabwe and South Africa) and northern Thailand. A household probability sample of 14,203 participants completed a survey including a scale measuring HIV/AIDS-related stigma and discrimination. Logistic regression models determined the associations between negative attitudes and perceived discrimination with individual history of HIV testing, knowledge of ARVs and communication regarding HIV/AIDS. Spearman's correlation coefficients determined the relationships between negative attitudes and perceived discrimination and HIV prevalence and ARV coverage at the site-level. Negative attitudes were related to never having tested for HIV, lacking knowledge of ARVs, and never having discussed HIV/AIDS. More negative attitudes were found in sites with the lowest HIV prevalence (i.e., Tanzania and Thailand) and more perceived discrimination against PLHA was found in sites with the lowest ARV coverage (i.e., Tanzania and Zimbabwe). Programs that promote widespread HIV testing and discussion of HIV/AIDS, as well as education regarding and universal access to ARVs, may reduce HIV/AIDS-related stigma and discrimination. PMID:19427086

  3. A qualitative analysis of barriers to accessing HIV/AIDS-related services among newly diagnosed HIV-positive men who have sex with men in China.

    PubMed

    Li, Haochu Howard; Holroyd, Eleanor; Li, Xiaoming; Lau, Joseph

    2015-01-01

    In China, specific HIV/AIDS-related services have been in place since 2004. However, utilisation of these services remains limited among people living with HIV. We explored barriers to accessing HIV/AIDS-related services from the perspective of newly diagnosed HIV-positive men who have sex with men. We conducted repeated in-depth interviews with 31 newly diagnosed HIV-positive men who have sex with men, using the socio-ecological framework and thematic content analysis. Multiple barriers for utilisation of HIV/AIDS-related services were identified, including perceptions of subjective health and poor quality of services, mental and emotional health problems, lack of trust and understanding of the services on offer, low economic status, lack of insurance, and high medical fees, being refused access to services, and restrictive attendance policies. The findings provide information on potential multi-level obstacles preventing newly diagnosed HIV-positive men who have sex with men to use services that they need. It is recommended that policy makers should create a trustful and non-discriminating environment and services integrating physical and mental healthcare. PMID:24626063

  4. Individual attitudes and perceived social norms: Reports on HIV/AIDS-related stigma among service providers in China

    PubMed Central

    Li, Li; Liang, Li-Jung; Wu, Zunyou; Lin, Chunqing; Wen, Yi

    2009-01-01

    This study examined HIV/AIDS-related stigma among Chinese service providers by comparing their personal attitudes toward people living with HIV/AIDS with their perception of social norms related to people living with HIV/AIDS. We randomly selected three provincial hospitals, four city/prefecture hospitals, 10 county hospitals, 18 township health clinics, and 54 village clinics from Yunnan, China. Doctors and nurses were randomly sampled proportionally to the doctor-nurse ratio of each hospital or clinic. Lab technicians were over-sampled in order to include an adequate representation in the analysis. A total of 1,101 service providers participated in a voluntary, anonymous survey where demographic characteristics, individual attitude and perceived social norms toward people living with HIV/AIDS, discrimination intent at work, general prejudicial attitude and knowledge on HIV/AIDS were measured. A majority of the sample demonstrated a similarity between their personal views and what they thought most people in society believe. Multiple logistic regressions revealed that participants who were younger or reported personal contact with people living with HIV/AIDS were significantly more likely to report personal attitudes toward the population that were more liberal than their perceived social norms. Holding a more liberal personal attitude toward people living with HIV/AIDS than perceived social norms was significantly and negatively related to the level of discrimination intent at work, perceived discrimination at interpersonal level and the level of general prejudicial attitude toward people living with HIV/AIDS. Results underscored the importance of understanding social norms and personal attitudes in studying HIV-related stigma and called for the incorporation of existing human capital into future HIV stigma reduction programs. Cette étude a examiné le VIH/SIDA lié à stigmatisation parmi les agences chinoises fournissant des soins en comparant leurs attitudes

  5. Effect of media use on HIV/AIDS-related knowledge and condom use in sub-Saharan Africa: a cross-sectional study.

    PubMed

    Jung, Minsoo; Arya, Monisha; Viswanath, Kasisomayajula

    2013-01-01

    It is known that the level of HIV/AIDS-related knowledge and the degree of condom use varies by socioeconomic status (SES). However, there is limited research on the effect of mass media use on HIV/AIDS-related cognitive and behavioral outcomes in low-income countries and how it might influence the association between SES and HIV-related outcomes. We investigated the moderating effect of media use on the relationship between SES and HIV/AIDS-related knowledge and condom use in sub-Saharan Africa in terms of communication inequalities. Cross-sectional data from the Demographic Health Surveys from 13 sub-Saharan countries (2004-10) were pooled. Gender-stratified multivariable poisson regression of 151,209 women and 68,890 men were used to calculate adjusted relative ratios and 95% confidence intervals for the associations between SES, media use, HIV-related outcomes, and condom use. We found significant disparities in mass media use among people from different SES groups as well as among countries. Education and wealth are strongly and positively associated with awareness of HIV/AIDS and knowledge about transmission and prevention of HIV/AIDS and are significantly associated with condom use. These associations are attenuated when the use of various types of mass media is added to the models, with newspapers showing the strongest effect. The findings of this study suggest that media use has the potential to blunt the impact of socioeconomic status though not completely eliminate it. Thus, we need to pay attention to reducing communication inequalities among social groups and countries to moderate the effect of wealth and SES on HIV/AIDS. PMID:23874598

  6. HIV and/or AIDS-related deaths and modifiable risk factors: A descriptive study of medical admissions at Oshakati Intermediate Hospital in Northern Namibia

    PubMed Central

    Mgori, N.K.

    2015-01-01

    Background High rates of HIV infection have decreased life expectancy in many African countries. Regardless of worldwide efforts to escalate treatment, care and prevention strategies, the number of deaths due to AIDS-related disorders is still high. Local healthcare workers suspect that there are modifiable factors in the care of HIV and/or AIDS patients which can be identified and improved. Aim To describe the HIV and/or AIDS-related causes of adult mortality and identify modifiable factors amongst patients admitted to Oshakati Intermediate Hospital, northern Namibia. Methods Data was extracted retrospectively and coded using the modified CoDe protocol for AIDS. Modifiable factors relating to the patient, health system or clinical care were identified using a standardised data collection tool. Results A total of 177 HIV and/or AIDS patients were identified, 94 (53.1%) were male and 120 (68%) had a CD4 count of less than 200 cells/mL. The common HIV-related causes of death were tuberculosis (25.9%), renal failure (15.8%), Pneumocystis jirovecii pneumonia (11.3%), cryptococcal meningitis (9%), HIV wasting syndrome (7.9%) and AIDS-defining malignancy (7.9%). The analysis revealed 281 modifiable factors; patient-related factors were the most common (153 [54.4%]), followed by health system factors (97 [34.5%]) and healthcare personnel factors (31 [11%]). Conclusion Our findings have highlighted the challenges in overall HIV and/or AIDS inpatient care and surrounding primary care facilities. The identification of specific modifiable factors can be used to reduce mortality by providing training as well as rational monitoring, planning and resource allocation.

  7. Outcome of Patients with Relapsed/Refractory AIDS-Related Lymphoma Diagnosed 1999–2008 and Treated with Curative Intent in the AIDS Malignancy Consortium

    PubMed Central

    Bayraktar, U. D.; Ramos, J. C.; Petrich, A.; Gupta, N.; Lensing, S.; Moore, Page; Reid, E. G.; Aboulafia, D. M.; Ratner, L.; Mitsuyasu, R.; Cooley, Timothy; Henry, D. H.; Barr, P.; Noy, A.

    2012-01-01

    No comparative studies exist for relapsed/refractory (rel/rfr) AIDS-related lymphomas (ARLs). To determine practices over the last decade and to assess the outcomes of salvage chemotherapy with curative intent and autologous stem cell transplantation (ASCT), we retrospectively evaluated treatment outcomes in patients with rel/rfr ARL who were treated in 13 national AIDS Malignancy Consortium (AMC) sites between 1999 and 2008 (N=88). The most commonly used second line therapies were ICE (n=34), dose adjusted EPOCH (n=17), and ESHAP (n=11). The odds of achieving a response were lower for those with non-Hodgkin lymphoma (NHL) than those with HL and for those with primary refractory disease than those with relapse. Overall survival (OS) was significantly longer for those with relapsed disease compared to those with refractory disease and for those with non-Burkitt NHL compared to those with Burkitt. OS was longer in patients who underwent ASCT compared to those who did not (1-year OS: 63.2% vs. 37.2%). However, among 32 patients (36%) who achieved CR/PR after second-line therapy 1-year OS was not different between the 2 groups (87.5% for ASCT vs. 81.8% for non-ASCT). Long-term survival in some patients with rel/rfr ARL may be possible without transplant, although transplant remains the standard of care for chemotherapy sensitive disease. PMID:22642936

  8. Understanding the relationships among HIV/AIDS-related stigma, health service utilization, and HIV prevalence and incidence in Sub-Saharan Africa: a multi-level theoretical perspective.

    PubMed

    Williams, Leslie D

    2014-03-01

    HIV-positive individuals often face community-wide discrimination or public shame and humiliation as a result of their HIV-status. In Sub-Saharan Africa, high HIV incidence coupled with unique cultural contexts make HIV-positive individuals particularly likely to experience this kind of HIV/AIDS-related (HAR) stigma. To date, there is a relatively small amount of high-quality empirical literature specific to HAR stigma in this context, supporting the notion that a better understanding of this phenomenon is needed to inform potential interventions. This paper provides a thorough review of the literature specific to HAR stigma in Sub-Saharan Africa, finding (a) qualitative support for the existence of important relationships between HAR stigma and health service utilization and barriers; (b) a need for more quantitative study of stigma and its relationships both to health service utilization and to HIV outcomes directly; and (c) a disconnect between methodological techniques used in this context-specific literature and well-known theories about stigma as a general phenomenon. This paper then draws from its empirical literature review, as well as from well-known theoretical frameworks from multiple disciplines, to propose a theoretical framework for the ecological and multilevel relationships among HAR stigma, health service utilization, and HIV outcomes in this context. PMID:24477769

  9. Large B-cell lymphoma in a dog: A cyto-histopathological evaluation and Immunophenotyping according to WHO classification for canine lymphomas

    PubMed Central

    Nikousefat, Zahra; Hashemnia, Mohammad; Javdani, Moosa

    2016-01-01

    In the present study, we described cyto-histopathological features and immunophenotyping of the large B-cell lymphoma in an 8-year-old mixed breed dog with applying the World Health Organization (WHO) system of classification of canine lymphomas. In fine-needle aspiration (FNA), lymph nodes were involved by neoplastic cells of intermediate to large size with deep blue cytoplasm; consist of centroblasts, immunoblast and medium-sized cells. Histopathologically, the follicles and sinuses of lymph nodes were replaced by sheets of numerous immunoblasts (less than 90.0% of total cells) and centroblasts. Numerous mitotic figures were also observed. Immunohistochemical analysis presented that the neoplastic cells express B-cell phenotype CD20 and CD79a, but do not stain for T phenotype CD3. On the basis of cytology, histopathology and immunohistochemical findings, the present tumor was diagnosed as diffuse large B-cell lymphoma, high-grade centroblastic type (DLBCL-CB) according to WHO histological classification. Applying this classification system for diagnosis of canine lymphomas is very useful and has a high accuracy and consistency. However, further co-operative studies between clinicians and pathologists should be performed, in order to improve the effectiveness of this classification. PMID:27226892

  10. IgM, IgG and IgA rheumatoid factors and circulating immune complexes in patients with AIDS and AIDS-related complex with serological abnormalities.

    PubMed Central

    Procaccia, S; Lazzarin, A; Colucci, A; Gasparini, A; Forcellini, P; Lanzanova, D; Foppa, C U; Novati, R; Zanussi, C

    1987-01-01

    To investigate some humoral aspects which may reflect the involvement of B lymphocytes in the acquired immunodeficiency syndrome (AIDS), we used an enzyme-linked immunoassay (ELISA) to determine the levels of IgM, IgG and IgA rheumatoid factors (RF) in 16 patients suffering from full-blown AIDS and 32 patients with AIDS-related complex (ARC), in the clinical form of lymphoadenopathy syndrome (LAS), compared with 40 healthy, young heterosexual subjects. Both AIDS and ARC patients showed a greater incidence of high IgM RF levels, with mean values significantly higher than controls, but with no differences between the two pathological groups. IgG RF behaviour was similar in the two patient populations and the healthy subjects. IgA RF were significantly raised in AIDS and ARC. Further information on RF was obtained by determination of the immunoglobulin levels of the respective isotypes in the same patients. Mean IgG levels were above normal in AIDS and ARC patients, but the latter group showed a higher incidence of increased values and higher mean levels. The IgA isotype was significantly increased mainly in AIDS patients. The behaviour of IgM was virtually the same in the three groups studied. A difference between AIDS and ARC patients was established by the detection of circulating immune-complexes (IC) by the C1q-binding and CIC-conglutinin assays. IC were significantly high, by both methods, only in the ARC group, but normal or very low in AIDS. These overall findings suggest once again the impairment of B cell function in AIDS, with prevalent hyperactivation in ARC and exhaustion in full-blown AIDS, and apparent preservation, in the latter group, of the antibody responses which are more closely related to the activity of subsets of T helper cells. PMID:3608224

  11. High-dose cytosine-arabinoside and cisplatin regimens as salvage therapy for refractory or relapsed AIDS-related non-Hodgkin's lymphoma.

    PubMed

    Bi, J; Espina, B M; Tulpule, A; Boswell, W; Levine, A M

    2001-12-15

    No effective salvage regimen has been defined for patients with AIDS-related non-Hodgkin's lymphoma (AIDS-NHL) who do not respond to first-line chemotherapy that contains anthracycline. Combined dexamethasone, cytosine arabinoside, and cisplatin (DHAP) and etoposide, methylprednisolone, cytosine arabinoside, and cisplatin (ESHAP) have shown good response rates in HIV-negative patients with relapsed lymphomas. We retrospectively analyzed patients with refractory or relapsed AIDS-NHL who had been treated with either DHAP or ESHAP to evaluate the feasibility and efficacy of these regimens. Twenty-six patients with refractory or relapsed AIDS-NHL were treated between 1990 and 1999 either with DHAP ( n = 13) or with ESHAP ( n = 13). Only 1 patient from each group (8%) had achieved complete remission with any previous therapy, and most had progressive disease after the regimen immediately preceding DHAP or ESHAP. In the ESHAP group, 4 patients (31%) achieved complete remission (CR) and 3 patients (23%) attained partial remission (PR) for an overall response rate of 54%. The median survival was 7.1 months (range, 1-58.9+ months) from the time ESHAP was begun. Among the 3 patients with primary refractory lymphoma, there was 1 CR, 1 PR, and one patient with stable disease. In contrast, only 1 PR (7%) was observed with DHAP; the median survival was 3 months. Myelosuppression was the most significant toxicity with grade 4 neutropenia occurring in all who received ESHAP and in 54% of patients treated with DHAP. Neutropenic fever occurred in 8 (62%) ESHAP-treated and 6 (46%) DHAP-treated patients. Although hematologic toxicity is profound, ESHAP appears to be an active salvage regimen for patients with relapsed or refractory AIDS-NHL. PMID:11744828

  12. Correlation between viral load, plasma levels of CD4 - CD8 T lymphocytes and AIDS-related oral diseases: a multicentre study on 30 HIV+ children in the HAART era.

    PubMed

    Nesti, M; Carli, E; Giaquinto, C; Rampon, O; Nastasio, S; Giuca, M R

    2012-01-01

    This experimental retrospective multicenter study carried out on 30 seropositive children treated with Highly Active Antiretroviral Therapy (HAART), between the ages of 18 months and 14 years, in the clinical categories Centers for Disease Control (CDC) classification 1993 A (mildly symptomatic), B (moderately symptomatic) and C (severely symptomatic) aims to: 1) clinically and immunologically demonstrate the therapeutic benefits of HAART; 2) monitor the frequency of AIDS-related oral diseases in seropositive children with HAART therapy; 3) monitor the plasma levels of total CD4, CD4 percent, CD8 percent, CD4-CD8 lymphocytes and viral load from 1997 to 30 April, 2011. The statistic methods used are the analysis of covariance and the Bonferroni Test. More than 100 AIDS-related oral diseases were found in the study samples, the most frequent being: oral candidiasis, oropharyngeal candidiasis, HSV-1 herpetic esophagyitis, herpetic gingivolstomatitis (RHOG), recurrent aphthous stomatitis (RAS), parotid swelling, oral hairy leukoplakia (OHL), Herpes simplex 1 (HSV-1), linear gingival erythema (LGE), necrotizing gingivitis (NUG), facial lipodistrophy, facial-cervical lymphadenopathy (FCL), xerostomia, dysgeusia, hyposmia, oral mucosa hyperpigmentation (OMP). The Bonferroni test showed a significant difference between the mean plasma values (mpVTL) of total CD4, CD4 percentage, CD4-CD8 T lymphocytes and Viral Load (VL) of the various oral diseases found in the study samples. The therapeutic benefits of HAART are: immune reconstitution; reduction of the HIV/AIDS-related stomatology diseases; prevention and cure of the AIDS correlated neoplasias; reduction in maternal-fetal transmission of the HIV virus. The negative effects of HAART in relation to odontostomatolgy are: increase in oral lesions from HPV; xerostomia; dysgeusia/ageusia, hyposmia, perioral paresthesia; hyperpigmentation of oral mucosa; facial lipodystrophy, recurrent aphthous stomatitis (RAS). No case of

  13. Epstein-Barr virus-positive diffuse large B-cell lymphoma in children: a disease reminiscent of Epstein-Barr virus-positive diffuse large B-cell lymphoma of the elderly.

    PubMed

    Uccini, Stefania; Al-Jadiry, Mazin F; Scarpino, Stefania; Ferraro, Daniela; Alsaadawi, Adel R; Al-Darraji, Amir F; Moleti, Maria Luisa; Testi, Anna Maria; Al-Hadad, Salma A; Ruco, Luigi

    2015-05-01

    Pediatric Epstein-Barr virus (EBV)-positive diffuse large B-cell lymphoma (EBV+ DLBCL) is a rare disease in nonimmunocompromised hosts. In a review of 231 cases of malignant lymphoma (87 Hodgkin lymphoma and 144 non-Hodgkin lymphoma) occurring in Iraqi children, 7 cases (5% of NHLs) were classified as EBV+ DLBCL. Six children presented with nodal disease, and 1 presented with extranodal localization (bone). In all cases, the disease was at an advanced clinical stage (III/IV). Evidence of immunodeficiency (Evans syndrome and selective IgA deficiency) was observed in a single case. Two cases were "monomorphic" with immunoblastic histology, and 5 cases were "polymorphic" with histologic aspects reminiscent of nodular lymphocyte-predominant Hodgkin lymphoma (2 cases) and of CD30+ classical Hodgkin lymphoma (3 cases). In all cases, tumor cells were EBV infected (EBER+/LMP-1+), were medium-large B-cells (CD20+/CD79a+/PAX-5+/BOB-1+/OCT-2+) of non-germinal center (non-GC) origin (CD10-/MUM-1+), and had high proliferative activity (50%-70%). Chromosomal translocations involving BCL2, MYC, and IGH genes were not observed. IGH monoclonality could be demonstrated in 3 of 3 investigated cases. Six cases of EBV-negative DLBCL (4% of NHL) were present in the same series. All had monomorphic histology with centroblastic/immunoblastic morphology; 3 cases were of GC type and 3 of non-GC type. Our findings indicate that in Iraq, DLBCLs are 9% of NHLs. Moreover, 2 different types of the disease do exist; the EBV-positive cases, with strong histologic and immunohistochemical resemblance with EBV+ DLBCL of the elderly, and the EBV-negative cases, which are similar to the pediatric DLBCL usually observed in Western populations. PMID:25704629

  14. AIDS-related primary cardiac lymphoma with right-sided heart failure and high-grade AV block: insights from magnetic resonance imaging.

    PubMed

    Llitjos, J-F; Redheuil, A; Puymirat, E; Vedrenne, G; Danchin, N

    2014-04-01

    A 44-year-old patient, with personal history of AIDS, was referred to our emergency unit with tachycardia and moderate signs of right-sided heart failure. The cardiac MRI study showed an impairment of the right ventricular free and inferior wall and the interventricular septum. The mass was characterized by notable heterogeneity with mixed areas of hypo- and hypersignal intensity in SSFP and T2-weighted images with fat saturation. There was global hyperenhancement of the mass after gadolinium contrast injection on T1-weighted images with and without fat saturation. The entire right coronary artery was included into the infiltrative mass. One day after the admission, the patient suddenly presented a paroxysmal third degree atrioventricular block, permanently corrected by an implanted cardiac pacemaker. Endomyocardial biopsy conformed the diagnosis of B-cell lymphoma. The patient died 4months after the diagnosis of acute heart failure with multi-organ dysfunction, after a short period of improvement under chemotherapy. We present this case to highlight the importance to consider that a large, solitary, right atrial mass in conjunction with pericardial effusion in a patient with HIV infection should lead to consider, as soon as possible, the diagnosis of lymphoma. MRI has explained the conduction disorders by showing the septal extension of the mass, and by demonstrating right coronary artery involvement. PMID:23830566

  15. Vorinostat and Combination Chemotherapy With Rituximab in Treating Patients With HIV-Related Diffuse Large B-Cell Non-Hodgkin Lymphoma or Other Aggressive B-Cell Lymphomas

    ClinicalTrials.gov

    2016-09-08

    AIDS-Related Diffuse Large Cell Lymphoma; AIDS-Related Plasmablastic Lymphoma; AIDS-Related Primary Effusion Lymphoma; Grade 3b Follicular Lymphoma; HIV Infection; Plasmablastic Lymphoma; Primary Effusion Lymphoma; Recurrent Adult Diffuse Large Cell Lymphoma; Recurrent Grade 3 Follicular Lymphoma; Stage I Adult Diffuse Large Cell Lymphoma; Stage I Grade 3 Follicular Lymphoma; Stage II Contiguous Adult Diffuse Large Cell Lymphoma; Stage II Grade 3 Contiguous Follicular Lymphoma; Stage II Grade 3 Non-Contiguous Follicular Lymphoma; Stage II Non-Contiguous Adult Diffuse Large Cell Lymphoma; Stage III Adult Diffuse Large Cell Lymphoma; Stage III Grade 3 Follicular Lymphoma; Stage IV Adult Diffuse Large Cell Lymphoma; Stage IV Grade 3 Follicular Lymphoma

  16. Cilengitide (EMD 121974) in Treating Patients With Advanced Solid Tumors or Lymphoma

    ClinicalTrials.gov

    2013-01-23

    AIDS-related Peripheral/Systemic Lymphoma; AIDS-related Primary CNS Lymphoma; Anaplastic Large Cell Lymphoma; Angioimmunoblastic T-cell Lymphoma; Extranodal Marginal Zone B-cell Lymphoma of Mucosa-associated Lymphoid Tissue; Intraocular Lymphoma; Nodal Marginal Zone B-cell Lymphoma; Recurrent Adult Burkitt Lymphoma; Recurrent Adult Diffuse Large Cell Lymphoma; Recurrent Adult Diffuse Mixed Cell Lymphoma; Recurrent Adult Diffuse Small Cleaved Cell Lymphoma; Recurrent Adult Hodgkin Lymphoma; Recurrent Adult Immunoblastic Large Cell Lymphoma; Recurrent Adult Lymphoblastic Lymphoma; Recurrent Adult T-cell Leukemia/Lymphoma; Recurrent Cutaneous T-cell Non-Hodgkin Lymphoma; Recurrent Grade 1 Follicular Lymphoma; Recurrent Grade 2 Follicular Lymphoma; Recurrent Grade 3 Follicular Lymphoma; Recurrent Mantle Cell Lymphoma; Recurrent Marginal Zone Lymphoma; Recurrent Mycosis Fungoides/Sezary Syndrome; Recurrent Small Lymphocytic Lymphoma; Splenic Marginal Zone Lymphoma; Stage III Adult Burkitt Lymphoma; Stage III Adult Diffuse Large Cell Lymphoma; Stage III Adult Diffuse Mixed Cell Lymphoma; Stage III Adult Diffuse Small Cleaved Cell Lymphoma; Stage III Adult Hodgkin Lymphoma; Stage III Adult Immunoblastic Large Cell Lymphoma; Stage III Adult Lymphoblastic Lymphoma; Stage III Cutaneous T-cell Non-Hodgkin Lymphoma; Stage III Grade 1 Follicular Lymphoma; Stage III Grade 2 Follicular Lymphoma; Stage III Grade 3 Follicular Lymphoma; Stage III Mantle Cell Lymphoma; Stage III Marginal Zone Lymphoma; Stage III Mycosis Fungoides/Sezary Syndrome; Stage III Small Lymphocytic Lymphoma; Stage IV Adult Burkitt Lymphoma; Stage IV Adult Diffuse Large Cell Lymphoma; Stage IV Adult Diffuse Mixed Cell Lymphoma; Stage IV Adult Diffuse Small Cleaved Cell Lymphoma; Stage IV Adult Hodgkin Lymphoma; Stage IV Adult Immunoblastic Large Cell Lymphoma; Stage IV Adult Lymphoblastic Lymphoma; Stage IV Cutaneous T-cell Non-Hodgkin Lymphoma; Stage IV Grade 1 Follicular Lymphoma; Stage IV Grade 2

  17. RO4929097 and Capecitabine in Treating Patients With Refractory Solid Tumors

    ClinicalTrials.gov

    2014-11-06

    Adult Grade III Lymphomatoid Granulomatosis; Adult Nasal Type Extranodal NK/T-cell Lymphoma; AIDS-related Diffuse Large Cell Lymphoma; AIDS-related Diffuse Mixed Cell Lymphoma; AIDS-related Diffuse Small Cleaved Cell Lymphoma; AIDS-related Immunoblastic Large Cell Lymphoma; AIDS-related Lymphoblastic Lymphoma; AIDS-related Peripheral/Systemic Lymphoma; AIDS-related Primary CNS Lymphoma; AIDS-related Small Noncleaved Cell Lymphoma; Anaplastic Large Cell Lymphoma; Angioimmunoblastic T-cell Lymphoma; Cutaneous B-cell Non-Hodgkin Lymphoma; Extranodal Marginal Zone B-cell Lymphoma of Mucosa-associated Lymphoid Tissue; HER2-negative Breast Cancer; HIV-associated Hodgkin Lymphoma; Intraocular Lymphoma; Male Breast Cancer; Nodal Marginal Zone B-cell Lymphoma; Post-transplant Lymphoproliferative Disorder; Primary Central Nervous System Hodgkin Lymphoma; Primary Central Nervous System Non-Hodgkin Lymphoma; Recurrent Adult Burkitt Lymphoma; Recurrent Adult Diffuse Large Cell Lymphoma; Recurrent Adult Diffuse Mixed Cell Lymphoma; Recurrent Adult Diffuse Small Cleaved Cell Lymphoma; Recurrent Adult Grade III Lymphomatoid Granulomatosis; Recurrent Adult Hodgkin Lymphoma; Recurrent Adult Immunoblastic Large Cell Lymphoma; Recurrent Adult Lymphoblastic Lymphoma; Recurrent Adult T-cell Leukemia/Lymphoma; Recurrent Breast Cancer; Recurrent Colon Cancer; Recurrent Cutaneous T-cell Non-Hodgkin Lymphoma; Recurrent Grade 1 Follicular Lymphoma; Recurrent Grade 2 Follicular Lymphoma; Recurrent Grade 3 Follicular Lymphoma; Recurrent Mantle Cell Lymphoma; Recurrent Marginal Zone Lymphoma; Recurrent Mycosis Fungoides/Sezary Syndrome; Recurrent Rectal Cancer; Recurrent Small Lymphocytic Lymphoma; Small Intestine Lymphoma; Splenic Marginal Zone Lymphoma; Stage III Adult Burkitt Lymphoma; Stage III Adult Diffuse Large Cell Lymphoma; Stage III Adult Diffuse Mixed Cell Lymphoma; Stage III Adult Diffuse Small Cleaved Cell Lymphoma; Stage III Adult Hodgkin Lymphoma; Stage III Adult Immunoblastic

  18. Treatment Options for AIDS-Related Lymphoma

    MedlinePlus

    ... the picture. This procedure is also called nuclear magnetic resonance imaging (NMRI). Lumbar puncture : A procedure used to collect cerebrospinal fluid (CSF) from the spinal column . This is done ...

  19. Treatment Option Overview (AIDS Related-Lymphoma)

    MedlinePlus

    ... the picture. This procedure is also called nuclear magnetic resonance imaging (NMRI). Lumbar puncture : A procedure used to collect cerebrospinal fluid (CSF) from the spinal column . This is done ...

  20. Stages of AIDS-Related Lymphoma

    MedlinePlus

    ... the picture. This procedure is also called nuclear magnetic resonance imaging (NMRI). Lumbar puncture : A procedure used to collect cerebrospinal fluid (CSF) from the spinal column . This is done ...

  1. Dentistry and HIV/AIDS related stigma

    PubMed Central

    Elizondo, Jesus Eduardo; Treviño, Ana Cecilia; Violant, Deborah

    2015-01-01

    OBJECTIVE To analyze HIV/AIDS positive individual’s perception and attitudes regarding dental services. METHODS One hundred and thirty-four subjects (30.0% of women and 70.0% of men) from Nuevo León, Mexico, took part in the study (2014). They filled out structured, analytical, self-administered, anonymous questionnaires. Besides the sociodemographic variables, the perception regarding public and private dental services and related professionals was evaluated, as well as the perceived stigma associated with HIV/AIDS, through a Likert-type scale. The statistical evaluation included a factorial and a non-hierarchical cluster analysis. RESULTS Social inequalities were found regarding the search for public and private dental professionals and services. Most subjects reported omitting their HIV serodiagnosis and agreed that dentists must be trained and qualified to treat patients with HIV/AIDS. The factorial analysis revealed two elements: experiences of stigma and discrimination in dental appointments and feelings of concern regarding the attitudes of professionals or their teams concerning patients’ HIV serodiagnosis. The cluster analysis identified three groups: users who have not experienced stigma or discrimination (85.0%); the ones who have not had those experiences, but feel somewhat concerned (12.7%); and the ones who underwent stigma and discrimination and feel concerned (2.3%). CONCLUSIONS We observed a low percentage of stigma and discrimination in dental appointments; however, most HIV/AIDS patients do not reveal their serodiagnosis to dentists out of fear of being rejected. Such fact implies a workplace hazard to dental professionals, but especially to the very own health of HIV/AIDS patients, as dentists will not be able to provide them a proper clinical and pharmaceutical treatment. PMID:26538100

  2. Women and AIDS-Related Concerns

    PubMed Central

    Cochran, Susan D.; Mays, Vickie M.

    2014-01-01

    Acquired Immunodeficiency Syndrome (AIDS) has important implications for the practice of psychology. As the epidemic continues, the role of behavior change and psychosocial factors in the spread and transmission of Human Immunodeficiency Virus (HIV) infections assumes increasing significance. Psychologists, as behavior change experts, have a special and challenging role to play in educating the public, particularly women, about AIDS. This article examines AIDS- and HIV-related concerns in women with a focus on the personal dilemmas for the practicing psychologist, problems in health behavior advocacy, and methods and pitfalls in modifying sexual behaviors. PMID:2930055

  3. Bcl-2 protein expression is the strongest independent prognostic factor of survival in primary cutaneous large B-cell lymphomas.

    PubMed

    Grange, Florent; Petrella, Tony; Beylot-Barry, Marie; Joly, Pascal; D'Incan, Michel; Delaunay, Michele; Machet, Laurent; Avril, Marie-Francoise; Dalac, Sophie; Bernard, Philippe; Carlotti, Agnes; Esteve, Eric; Vergier, Beatrice; Dechelotte, Pierre; Cassagnau, Elisabeth; Courville, Philippe; Saiag, Philippe; Laroche, Liliane; Bagot, Martine; Wechsler, Janine

    2004-05-15

    Bcl-2 protein expression has been associated with poor prognosis in patients with noncutaneous diffuse large B-cell lymphomas. In primary cutaneous large B-cell lymphomas, the location on the leg, the round-cell morphology defined as the predominance of centroblasts and immunoblasts over large centrocytes, and multiple skin lesions were identified as adverse prognostic factors. The prognostic value of bcl-2 protein expression has not been studied in large series of patients. We evaluated 80 primary cutaneous large B-cell lymphomas collected by the French Study Group on Cutaneous Lymphomas. The prognostic value of age, sex, number of lesions, cutaneous extent, location, serum lactate dehydrogenase (LDH) level, B symptoms, morphology, and bcl-2 protein expression was studied. The overall 5-year specific survival rate was 65%. In univariate analysis, advanced age, multiple skin lesions (n = 48), location on the leg (n = 25), round-cell morphology (n = 32), and bcl-2 expression (n = 39) were significantly related to death from lymphoma. In multivariate analysis, bcl-2 expression (P =.0003), multiple skin lesions (P =.004), and age remained independent prognostic factors. The 5-year specific survival rates in bcl-2-positive and bcl-2-negative patients were 41% and 89%, respectively (P <.0001). A new prognostic classification of primary cutaneous B-cell lymphoma should be based primarily on bcl-2 protein expression rather than the location of skin lesions. PMID:14726400

  4. Thinking large.

    PubMed

    Devries, Egbert

    2016-05-01

    Egbert Devries was brought up on a farm in the Netherlands and large animal medicine has always been his area of interest. After working in UK practice for 12 years he joined CVS and was soon appointed large animal director with responsibility for building a stronger large animal practice base. PMID:27154956

  5. 17-N-Allylamino-17-Demethoxygeldanamycin in Treating Patients With Advanced Epithelial Cancer, Malignant Lymphoma, or Sarcoma

    ClinicalTrials.gov

    2013-02-06

    AIDS-related Peripheral/Systemic Lymphoma; AIDS-related Primary CNS Lymphoma; Anaplastic Large Cell Lymphoma; Angioimmunoblastic T-cell Lymphoma; Chondrosarcoma; Extranodal Marginal Zone B-cell Lymphoma of Mucosa-associated Lymphoid Tissue; Intraocular Lymphoma; Metastatic Ewing Sarcoma/Peripheral Primitive Neuroectodermal Tumor; Metastatic Osteosarcoma; Nodal Marginal Zone B-cell Lymphoma; Ovarian Sarcoma; Primary Central Nervous System Non-Hodgkin Lymphoma; Recurrent Adult Burkitt Lymphoma; Recurrent Adult Diffuse Large Cell Lymphoma; Recurrent Adult Diffuse Mixed Cell Lymphoma; Recurrent Adult Diffuse Small Cleaved Cell Lymphoma; Recurrent Adult Hodgkin Lymphoma; Recurrent Adult Immunoblastic Large Cell Lymphoma; Recurrent Adult Lymphoblastic Lymphoma; Recurrent Adult Soft Tissue Sarcoma; Recurrent Adult T-cell Leukemia/Lymphoma; Recurrent Cutaneous T-cell Non-Hodgkin Lymphoma; Recurrent Ewing Sarcoma/Peripheral Primitive Neuroectodermal Tumor; Recurrent Grade 1 Follicular Lymphoma; Recurrent Grade 2 Follicular Lymphoma; Recurrent Grade 3 Follicular Lymphoma; Recurrent Mantle Cell Lymphoma; Recurrent Marginal Zone Lymphoma; Recurrent Mycosis Fungoides/Sezary Syndrome; Recurrent Osteosarcoma; Recurrent Small Lymphocytic Lymphoma; Recurrent Uterine Sarcoma; Small Intestine Lymphoma; Splenic Marginal Zone Lymphoma; Stage IV Adult Burkitt Lymphoma; Stage IV Adult Diffuse Large Cell Lymphoma; Stage IV Adult Diffuse Mixed Cell Lymphoma; Stage IV Adult Diffuse Small Cleaved Cell Lymphoma; Stage IV Adult Hodgkin Lymphoma; Stage IV Adult Immunoblastic Large Cell Lymphoma; Stage IV Adult Lymphoblastic Lymphoma; Stage IV Adult Soft Tissue Sarcoma; Stage IV Adult T-cell Leukemia/Lymphoma; Stage IV Cutaneous T-cell Non-Hodgkin Lymphoma; Stage IV Grade 1 Follicular Lymphoma; Stage IV Grade 2 Follicular Lymphoma; Stage IV Grade 3 Follicular Lymphoma; Stage IV Mantle Cell Lymphoma; Stage IV Marginal Zone Lymphoma; Stage IV Mycosis Fungoides/Sezary Syndrome; Stage IV Small

  6. An unusual case of anaplastic lymphoma kinase-positive large B-cell lymphoma in an elderly patient: A case report and discussion

    PubMed Central

    XIONG, HANZHEN; LIU, SHAO-YAN; YANG, YUE-XIN; TAN, XUE-XIAN; LUO, QIU-PING; PENG, JUAN; XIONG, ZHONG-TANG; CHEN, HUI; CHEN, JUAN; LI, ZHI; JIANG, QING-PING

    2016-01-01

    We present an unusual case of anaplastic lymphoma kinase (ALK)-positive large B-cell lymphoma, with rapid clinical progression, which occurred in a 90-year-old male patient. The patient presented with numerous enlarged lymph nodes in the neck and mediastinum. Histopathological analysis of a single lymph node detected diffuse large immunoblastic- or plasmablastic-like tumor cells, which were strongly immunoreactive for ALK in a granular cytoplasmic distribution, but negative for the expression of CD20 and CD79a. In addition, polymerase chain reaction assays were unable to detect clonal rearrangements of the T cell receptor-γ and immunoglobulin heavy chain genes in the tumor lesion, and in situ hybridization tested negative for infection with Epstein-Barr virus. The patient underwent a single cycle of chemotherapy using the cyclophosphamide, doxorubicin, vincristine, prednisone, and etoposide (E-CHOP) regimen; however, the patient developed pleural effusions with respiratory distress, associated with clinical deterioration. The patient succumbed to the disease within 4 months of initial presentation. To the best of our knowledge, this is the eldest patient with this type of lymphoma to be reported in the literature. PMID:27168806

  7. Genetic Testing Plus Irinotecan in Treating Patients With Solid Tumors or Lymphoma

    ClinicalTrials.gov

    2013-01-23

    AIDS-related Peripheral/Systemic Lymphoma; AIDS-related Primary CNS Lymphoma; Anaplastic Large Cell Lymphoma; Angioimmunoblastic T-cell Lymphoma; Extranodal Marginal Zone B-cell Lymphoma of Mucosa-associated Lymphoid Tissue; Intraocular Lymphoma; Nodal Marginal Zone B-cell Lymphoma; Primary Central Nervous System Non-Hodgkin Lymphoma; Recurrent Adult Burkitt Lymphoma; Recurrent Adult Diffuse Large Cell Lymphoma; Recurrent Adult Diffuse Mixed Cell Lymphoma; Recurrent Adult Diffuse Small Cleaved Cell Lymphoma; Recurrent Adult Hodgkin Lymphoma; Recurrent Adult Immunoblastic Large Cell Lymphoma; Recurrent Adult Lymphoblastic Lymphoma; Recurrent Adult T-cell Leukemia/Lymphoma; Recurrent Cutaneous T-cell Non-Hodgkin Lymphoma; Recurrent Grade 1 Follicular Lymphoma; Recurrent Grade 2 Follicular Lymphoma; Recurrent Grade 3 Follicular Lymphoma; Recurrent Mantle Cell Lymphoma; Recurrent Marginal Zone Lymphoma; Recurrent Mycosis Fungoides/Sezary Syndrome; Recurrent Small Lymphocytic Lymphoma; Small Intestine Lymphoma; Splenic Marginal Zone Lymphoma; Stage III Adult Burkitt Lymphoma; Stage III Adult Diffuse Large Cell Lymphoma; Stage III Adult Diffuse Mixed Cell Lymphoma; Stage III Adult Diffuse Small Cleaved Cell Lymphoma; Stage III Adult Hodgkin Lymphoma; Stage III Adult Immunoblastic Large Cell Lymphoma; Stage III Adult Lymphoblastic Lymphoma; Stage III Adult T-cell Leukemia/Lymphoma; Stage III Cutaneous T-cell Non-Hodgkin Lymphoma; Stage III Grade 1 Follicular Lymphoma; Stage III Grade 2 Follicular Lymphoma; Stage III Grade 3 Follicular Lymphoma; Stage III Mantle Cell Lymphoma; Stage III Marginal Zone Lymphoma; Stage III Mycosis Fungoides/Sezary Syndrome; Stage III Small Lymphocytic Lymphoma; Stage IV Adult Burkitt Lymphoma; Stage IV Adult Diffuse Large Cell Lymphoma; Stage IV Adult Diffuse Mixed Cell Lymphoma; Stage IV Adult Diffuse Small Cleaved Cell Lymphoma; Stage IV Adult Hodgkin Lymphoma; Stage IV Adult Immunoblastic Large Cell Lymphoma; Stage IV Adult Lymphoblastic

  8. Fludarabine and Total-Body Irradiation Followed By Donor Stem Cell Transplant and Cyclosporine and Mycophenolate Mofetil in Treating HIV-Positive Patients With or Without Cancer

    ClinicalTrials.gov

    2015-08-28

    Accelerated Phase Chronic Myelogenous Leukemia; Acute Undifferentiated Leukemia; Adult Acute Lymphoblastic Leukemia in Remission; Adult Acute Myeloid Leukemia in Remission; Adult Acute Myeloid Leukemia With 11q23 (MLL) Abnormalities; Adult Acute Myeloid Leukemia With Del(5q); Adult Acute Myeloid Leukemia With Inv(16)(p13;q22); Adult Acute Myeloid Leukemia With t(15;17)(q22;q12); Adult Acute Myeloid Leukemia With t(16;16)(p13;q22); Adult Acute Myeloid Leukemia With t(8;21)(q22;q22); Adult Grade III Lymphomatoid Granulomatosis; Adult Nasal Type Extranodal NK/T-cell Lymphoma; Aggressive NK-cell Leukemia; AIDS-related Diffuse Large Cell Lymphoma; AIDS-related Diffuse Mixed Cell Lymphoma; AIDS-related Diffuse Small Cleaved Cell Lymphoma; AIDS-related Immunoblastic Large Cell Lymphoma; AIDS-related Lymphoblastic Lymphoma; AIDS-related Peripheral/Systemic Lymphoma; AIDS-related Primary CNS Lymphoma; AIDS-related Small Noncleaved Cell Lymphoma; Anaplastic Large Cell Lymphoma; Angioimmunoblastic T-cell Lymphoma; Blastic Phase Chronic Myelogenous Leukemia; Childhood Acute Lymphoblastic Leukemia in Remission; Childhood Acute Myeloid Leukemia in Remission; Childhood Burkitt Lymphoma; Childhood Chronic Myelogenous Leukemia; Childhood Diffuse Large Cell Lymphoma; Childhood Grade III Lymphomatoid Granulomatosis; Childhood Immunoblastic Large Cell Lymphoma; Childhood Myelodysplastic Syndromes; Childhood Nasal Type Extranodal NK/T-cell Lymphoma; Chronic Eosinophilic Leukemia; Chronic Myelomonocytic Leukemia; Chronic Neutrophilic Leukemia; Chronic Phase Chronic Myelogenous Leukemia; Contiguous Stage II Adult Burkitt Lymphoma; Contiguous Stage II Adult Diffuse Large Cell Lymphoma; Contiguous Stage II Adult Diffuse Mixed Cell Lymphoma; Contiguous Stage II Adult Diffuse Small Cleaved Cell Lymphoma; Contiguous Stage II Adult Immunoblastic Large Cell Lymphoma; Contiguous Stage II Adult Lymphoblastic Lymphoma; Contiguous Stage II Grade 1 Follicular Lymphoma; Contiguous Stage II Grade 2

  9. Primary mediastinal large B-cell lymphoma and its mimickers: a rare case report with literature review.

    PubMed

    Win, T T; Kamaludin, Z; Husin, A

    2016-08-01

    Primary mediastinal large B-cell lymphoma (PMLBL) is an uncommon non-Hodgkin lymphoma with a distinct clinicopathological entity in the WHO classification of lymphoid malignancies. It is known to originate from B-cells of the thymus. It mimics thymic neoplasms and other lymphomas clinically and histopathologically. We reported a 33-year-old obese man who presented with shortness of breath off and on for 4 years. Radiologically, there was a huge anterior mediastinal mass. Tru-cut biopsy was initially diagnosed as type-A thymoma. Histopathological examination of the excised specimen revealed PMLBL with stromal fibrosis and sclerosis which created a diagnostic difficulty. The neoplastic cells varied from medium-sized to large pleomorphic cells, including mononuclear cells with centroblastic and immunoblastic features as well as bi-lobed Reed Sternberg (RS)-like cells and horse-shoe like hallmark cells. Some interlacing spindle cells and epithelioid cells were also present. Immunohistochemically, tumour cells expressed diffuse positivity for LCA, CD20, CD79a, CD23, Bcl2, MUM-1 and heterogenous positivity for CD30 and EMA, and were negative for CD10, CD15 and ALK. Ki67 scoring was very high. Tumour cells infiltrated into peri-thymic fat and pericardium. No malignant cells were detected in the pleural fluid and there was no bone marrow infiltration. The patient showed partial response to 6 cycles of RICE chemotherapy, and was planned for second line chemotherapy using hyper-CVAD regimen followed by autologous stem cell transplantation. This case illustrates the importance of thorough sampling and immunohistochemistry in differentiating PMLBL from its differential diagnoses. PMID:27568673

  10. Immunophenotypic and genotypic analysis of acquired immunodeficiency syndrome-related non-Hodgkin's lymphomas. Correlation with histologic features in 36 cases. French Study Group of Pathology for HIV-Associated Tumors.

    PubMed

    Raphael, M M; Audouin, J; Lamine, M; Delecluse, H J; Vuillaume, M; Lenoir, G M; Gisselbrecht, C; Lennert, K; Diebold, J

    1994-06-01

    High-grade B-cell-type non-Hodgkin's lymphomas are observed in 5% to 8% of patients positive for the human immunodeficiency virus. Nearly all cases belong to one of the three major histologic types: centroblastic or large noncleaved cell, immunoblastic and Burkitt's lymphoma, or small noncleaved cell. Some cases that are polymorphic are termed high-grade B-cell, not otherwise specified (NOS). The authors determined the immunophenotype of each histologic category of acquired immunodeficiency syndrome (AIDS)-related non-Hodgkins' lymphoma and sought a relationship with the presence of the Epstein-Barr virus (EBV). B-cell differentiation antigens, activation marker expression (human leukocyte antigen-DR, CD10, CD19, CD20, CD21, CD22, CD23, CD25, CD30, CD38), and epithelial membrane antigen were analyzed. The clonality was determined by the detection of cytoplasmic immunoglobulin, surface immunoglobulin, and the analysis of joining region (JH) immunoglobulin gene configuration by Southern blot. Epstein-Barr virus was detected either by Southern blot analysis using BamHI W probe fragment or by in situ hybridization with EBV-encoded RNA transcripts-1 specific probe. The immunophenotypic and genotypic results were compared with the morphology results and with the presence or absence of EBV. Burkitt's lymphomas were associated with EBV in 50% of cases, were monoclonal, and expressed mostly immunoglobulin (Ig) MK, CD10, CD19, CD20, CD22, and CD38. This immunophenotypic profile closely resembled those of the centroblastic cases (large noncleaved cell), in which EBV was absent. Epstein-Barr virus was associated with 90% of immunoblastic cases, and only CD10, CD20, and CD38 were expressed. CD71 was expressed in all categories of non-Hodgkin's lymphoma, and CD21 and CD23 were rarely expressed. Two cases of immunoblastic lymphoma and one case of high-grade B-NOS were polyclonal regarding JH rearrangement, but EBV tested with 1.9-Kb Xhol fragment was clonal. No significant

  11. AIDS-Related Stigma and Health Professionals in Puerto Rico

    PubMed Central

    Ruiz-Torres, Yamilette; Cintrón-Bou, Francheska N.; Varas-Díaz, Nelson

    2009-01-01

    This study addresses an important issue in the AIDS epidemic in Puerto Rico: AIDS stigma among health professionals and health profession students. AIDS stigma has been documented among health services providers such as doctors, nurses, psychologists, and social workers. It has detrimental effects of the services provided and the lives of people living with HIV/AIDS (PLWHA). The main objective of this study was to explore AIDS stigma manifestations among a sample composed of eighty health professionals and health profession students who participated in in-depth qualitative interviews. Four thematic categories stemmed from the data analysis process. These addressed the following subjects: social manifestations of stigma, stigma manifestations in the workplace, use of sensitive information to control PLWHA, and surveillance of PLWHA. Participants manifested instances of stigmatization they had witnessed in their work and training scenarios. Furthermore, they elaborated on the need to place effective surveillance mechanism on PLWHA in order to control the epidemic. PMID:21423837

  12. AIDS-related reasons for gay men's adoption of celibacy.

    PubMed

    Siegel, K; Raveis, V H

    1993-01-01

    Since it was first recognized that human immunodeficiency virus (HIV) infection could be sexually transmitted, celibacy has been advocated by some as the only unequivocally effective adaptation for avoiding the risk of infection. Others, however, have countered that few will be willing to be celibate and, further, that such behavior may have adverse psychosocial consequences. As part of a qualitative study of gay men's sexual decision-making in the context of the AIDS/HIV epidemic, we identified a subsample of respondents who had adopted celibacy for varying periods of time as an adaptation to the threat of AIDS/HIV infection. A content analysis of these men's interviews revealed 5 principal themes relating their reasons for choosing celibacy. PMID:8297710

  13. Sunitinib Malate in Treating HIV-Positive Patients With Cancer Receiving Antiretroviral Therapy

    ClinicalTrials.gov

    2014-03-14

    Accelerated Phase Chronic Myelogenous Leukemia; Acute Myeloid Leukemia With Multilineage Dysplasia Following Myelodysplastic Syndrome; Acute Undifferentiated Leukemia; Adult Acute Lymphoblastic Leukemia in Remission; Adult Acute Myeloid Leukemia With 11q23 (MLL) Abnormalities; Adult Acute Myeloid Leukemia With Del(5q); Adult Acute Myeloid Leukemia With Inv(16)(p13;q22); Adult Acute Myeloid Leukemia With t(15;17)(q22;q12); Adult Acute Myeloid Leukemia With t(16;16)(p13;q22); Adult Acute Myeloid Leukemia With t(8;21)(q22;q22); Adult Grade III Lymphomatoid Granulomatosis; Adult Langerhans Cell Histiocytosis; Adult Nasal Type Extranodal NK/T-cell Lymphoma; Aggressive NK-cell Leukemia; AIDS-related Diffuse Large Cell Lymphoma; AIDS-related Diffuse Mixed Cell Lymphoma; AIDS-related Diffuse Small Cleaved Cell Lymphoma; AIDS-related Immunoblastic Large Cell Lymphoma; AIDS-related Lymphoblastic Lymphoma; AIDS-related Malignancies; AIDS-related Small Noncleaved Cell Lymphoma; Anaplastic Large Cell Lymphoma; Angioimmunoblastic T-cell Lymphoma; Atypical Chronic Myeloid Leukemia, BCR-ABL1 Negative; Chronic Eosinophilic Leukemia; Chronic Myelomonocytic Leukemia; Chronic Neutrophilic Leukemia; Chronic Phase Chronic Myelogenous Leukemia; Clear Cell Renal Cell Carcinoma; Cutaneous B-cell Non-Hodgkin Lymphoma; de Novo Myelodysplastic Syndromes; Essential Thrombocythemia; Extramedullary Plasmacytoma; Extranodal Marginal Zone B-cell Lymphoma of Mucosa-associated Lymphoid Tissue; Hepatosplenic T-cell Lymphoma; HIV Infection; HIV-associated Hodgkin Lymphoma; Intraocular Lymphoma; Isolated Plasmacytoma of Bone; Light Chain Deposition Disease; Mast Cell Leukemia; Myelodysplastic Syndrome With Isolated Del(5q); Myelodysplastic/Myeloproliferative Neoplasm, Unclassifiable; Myeloid/NK-cell Acute Leukemia; Nodal Marginal Zone B-cell Lymphoma; Noncutaneous Extranodal Lymphoma; Osteolytic Lesions of Multiple Myeloma; Peripheral T-cell Lymphoma; Plasma Cell Neoplasm; Polycythemia Vera; Post

  14. Tanespimycin and Bortezomib in Treating Patients With Advanced Solid Tumors or Lymphomas

    ClinicalTrials.gov

    2014-02-21

    Adult Grade III Lymphomatoid Granulomatosis; AIDS-related Peripheral/Systemic Lymphoma; Anaplastic Large Cell Lymphoma; Angioimmunoblastic T-cell Lymphoma; Extranodal Marginal Zone B-cell Lymphoma of Mucosa-associated Lymphoid Tissue; Nodal Marginal Zone B-cell Lymphoma; Recurrent Adult Burkitt Lymphoma; Recurrent Adult Diffuse Large Cell Lymphoma; Recurrent Adult Diffuse Mixed Cell Lymphoma; Recurrent Adult Diffuse Small Cleaved Cell Lymphoma; Recurrent Adult Grade III Lymphomatoid Granulomatosis; Recurrent Adult Hodgkin Lymphoma; Recurrent Adult Immunoblastic Large Cell Lymphoma; Recurrent Adult Lymphoblastic Lymphoma; Recurrent Adult T-cell Leukemia/Lymphoma; Recurrent Cutaneous T-cell Non-Hodgkin Lymphoma; Recurrent Grade 1 Follicular Lymphoma; Recurrent Grade 2 Follicular Lymphoma; Recurrent Grade 3 Follicular Lymphoma; Recurrent Mantle Cell Lymphoma; Recurrent Marginal Zone Lymphoma; Recurrent Mycosis Fungoides/Sezary Syndrome; Recurrent Small Lymphocytic Lymphoma; Stage III Adult Burkitt Lymphoma; Stage III Adult Diffuse Large Cell Lymphoma; Stage III Adult Diffuse Mixed Cell Lymphoma; Stage III Adult Diffuse Small Cleaved Cell Lymphoma; Stage III Adult Hodgkin Lymphoma; Stage III Adult Immunoblastic Large Cell Lymphoma; Stage III Adult Lymphoblastic Lymphoma; Stage III Adult T-cell Leukemia/Lymphoma; Stage III Cutaneous T-cell Non-Hodgkin Lymphoma; Stage III Grade 1 Follicular Lymphoma; Stage III Grade 2 Follicular Lymphoma; Stage III Grade 3 Follicular Lymphoma; Stage III Mantle Cell Lymphoma; Stage III Marginal Zone Lymphoma; Stage III Mycosis Fungoides/Sezary Syndrome; Stage III Small Lymphocytic Lymphoma; Stage IV Adult Burkitt Lymphoma; Stage IV Adult Diffuse Large Cell Lymphoma; Stage IV Adult Diffuse Mixed Cell Lymphoma; Stage IV Adult Diffuse Small Cleaved Cell Lymphoma; Stage IV Adult Hodgkin Lymphoma; Stage IV Adult Immunoblastic Large Cell Lymphoma; Stage IV Adult Lymphoblastic Lymphoma; Stage IV Adult T-cell Leukemia/Lymphoma; Stage IV Cutaneous

  15. Imatinib Mesylate in Treating Patients With Advanced Cancer and Liver Dysfunction

    ClinicalTrials.gov

    2013-02-06

    Accelerated Phase Chronic Myelogenous Leukemia; Acute Undifferentiated Leukemia; AIDS-related Peripheral/Systemic Lymphoma; AIDS-related Primary CNS Lymphoma; Anaplastic Large Cell Lymphoma; Angioimmunoblastic T-cell Lymphoma; Atypical Chronic Myeloid Leukemia, BCR-ABL1 Negative; Blastic Phase Chronic Myelogenous Leukemia; Childhood Myelodysplastic Syndromes; Chronic Eosinophilic Leukemia; Chronic Myelogenous Leukemia, BCR-ABL1 Positive; Chronic Myelomonocytic Leukemia; Chronic Neutrophilic Leukemia; Chronic Phase Chronic Myelogenous Leukemia; de Novo Myelodysplastic Syndromes; Essential Thrombocythemia; Extramedullary Plasmacytoma; Extranodal Marginal Zone B-cell Lymphoma of Mucosa-associated Lymphoid Tissue; Gastrointestinal Stromal Tumor; Intraocular Lymphoma; Isolated Plasmacytoma of Bone; Meningeal Chronic Myelogenous Leukemia; Monoclonal Gammopathy of Undetermined Significance; Myelodysplastic/Myeloproliferative Neoplasm, Unclassifiable; Nodal Marginal Zone B-cell Lymphoma; Polycythemia Vera; Previously Treated Myelodysplastic Syndromes; Primary Central Nervous System Non-Hodgkin Lymphoma; Primary Myelofibrosis; Primary Systemic Amyloidosis; Progressive Hairy Cell Leukemia, Initial Treatment; Prolymphocytic Leukemia; Recurrent Adult Acute Lymphoblastic Leukemia; Recurrent Adult Acute Myeloid Leukemia; Recurrent Adult Burkitt Lymphoma; Recurrent Adult Diffuse Large Cell Lymphoma; Recurrent Adult Diffuse Mixed Cell Lymphoma; Recurrent Adult Diffuse Small Cleaved Cell Lymphoma; Recurrent Adult Hodgkin Lymphoma; Recurrent Adult Immunoblastic Large Cell Lymphoma; Recurrent Adult Lymphoblastic Lymphoma; Recurrent Adult T-cell Leukemia/Lymphoma; Recurrent Cutaneous T-cell Non-Hodgkin Lymphoma; Recurrent Grade 1 Follicular Lymphoma; Recurrent Grade 2 Follicular Lymphoma; Recurrent Grade 3 Follicular Lymphoma; Recurrent Mantle Cell Lymphoma; Recurrent Marginal Zone Lymphoma; Recurrent Mycosis Fungoides/Sezary Syndrome; Recurrent Small Lymphocytic Lymphoma; Refractory

  16. Large bowel resection - slideshow

    MedlinePlus

    ... this page: //medlineplus.gov/ency/presentations/100089.htm Large bowel resection - Series To use the sharing features ... 6 out of 6 Normal anatomy Overview The large bowel [large intestine or the colon] is part ...

  17. Instantons and Large N

    NASA Astrophysics Data System (ADS)

    Mariño, Marcos

    2015-09-01

    Preface; Part I. Instantons: 1. Instantons in quantum mechanics; 2. Unstable vacua in quantum field theory; 3. Large order behavior and Borel summability; 4. Non-perturbative aspects of Yang–Mills theories; 5. Instantons and fermions; Part II. Large N: 6. Sigma models at large N; 7. The 1=N expansion in QCD; 8. Matrix models and matrix quantum mechanics at large N; 9. Large N QCD in two dimensions; 10. Instantons at large N; Appendix A. Harmonic analysis on S3; Appendix B. Heat kernel and zeta functions; Appendix C. Effective action for large N sigma models; References; Author index; Subject index.

  18. Large intestine (colon) (image)

    MedlinePlus

    The large intestine is the portion of the digestive system most responsible for absorption of water from the indigestible ... the ileum (small intestine) passes material into the large intestine at the cecum. Material passes through the ...

  19. Large displacement spherical joint

    DOEpatents

    Bieg, Lothar F.; Benavides, Gilbert L.

    2002-01-01

    A new class of spherical joints has a very large accessible full cone angle, a property which is beneficial for a wide range of applications. Despite the large cone angles, these joints move freely without singularities.

  20. Large mode radius resonators

    NASA Technical Reports Server (NTRS)

    Harris, Michael R.

    1987-01-01

    Resonator configurations permitting operation with large mode radius while maintaining good transverse mode discrimination are considered. Stable resonators incorporating an intracavity telescope and unstable resonator geometries utilizing an output coupler with a Gaussian reflectivity profile are shown to enable large radius single mode laser operation. Results of heterodyne studies of pulsed CO2 lasers with large (11mm e sup-2 radius) fundamental mode sizes are presented demonstrating minimal frequency sweeping in accordance with the theory of laser-induced medium perturbations.

  1. Large Print Bibliography, 1990.

    ERIC Educational Resources Information Center

    South Dakota State Library, Pierre.

    This bibliography lists materials that are available in large print format from the South Dakota State Library. The annotated entries are printed in large print and include the title of the material and its author, call number, publication date, and type of story or subject area covered. Some recorded items are included in the list. The entries…

  2. Large wind turbine generators

    NASA Technical Reports Server (NTRS)

    Thomas, R. L.; Donovon, R. M.

    1978-01-01

    The development associated with large wind turbine systems is briefly described. The scope of this activity includes the development of several large wind turbines ranging in size from 100 kW to several megawatt levels. A description of the wind turbine systems, their programmatic status and a summary of their potential costs is included.

  3. LARGE BUILDING RADON MANUAL

    EPA Science Inventory

    The report summarizes information on how bilding systems -- especially the heating, ventilating, and air-conditioning (HVAC) system -- inclurence radon entry into large buildings and can be used to mitigate radon problems. It addresses the fundamentals of large building HVAC syst...

  4. Large Scale Computing

    NASA Astrophysics Data System (ADS)

    Capiluppi, Paolo

    2005-04-01

    Large Scale Computing is acquiring an important role in the field of data analysis and treatment for many Sciences and also for some Social activities. The present paper discusses the characteristics of Computing when it becomes "Large Scale" and the current state of the art for some particular application needing such a large distributed resources and organization. High Energy Particle Physics (HEP) Experiments are discussed in this respect; in particular the Large Hadron Collider (LHC) Experiments are analyzed. The Computing Models of LHC Experiments represent the current prototype implementation of Large Scale Computing and describe the level of maturity of the possible deployment solutions. Some of the most recent results on the measurements of the performances and functionalities of the LHC Experiments' testing are discussed.

  5. Large bowel resection - discharge

    MedlinePlus

    ... large bowel). You may also have had a colostomy . ... have diarrhea. You may have problems with your colostomy. ... protect it if needed. If you have a colostomy, follow care instructions from your provider. Sitting on ...

  6. Large Customers (DR Sellers)

    SciTech Connect

    Kiliccot, Sila

    2011-10-25

    State of the large customers for demand response integration of solar and wind into electric grid; openADR; CAISO; DR as a pseudo generation; commercial and industrial DR strategies; California regulations

  7. Large scale dynamic systems

    NASA Technical Reports Server (NTRS)

    Doolin, B. F.

    1975-01-01

    Classes of large scale dynamic systems were discussed in the context of modern control theory. Specific examples discussed were in the technical fields of aeronautics, water resources and electric power.

  8. Closed Large Cell Clouds

    Atmospheric Science Data Center

    2013-04-19

    article title:  Closed Large Cell Clouds in the South Pacific     ... unperturbed by cyclonic or frontal activity. When the cell centers are cloudy and the main sinking motion is concentrated at cell ...

  9. Large pore alumina

    SciTech Connect

    Ternan, M. )

    1994-04-01

    Earlier the authors reported preparation conditions for an alumina material which contained large diameter macropores (0.1-100 [mu]). The preparation variable that caused the formation of the uncommonly large macropores was the large acid/alumina ratios which were very much greater than the ones used in the preparation of conventional porous aluminas. The alumina material had large BET surface areas (200 m[sup 2]/g) and small mercury porosimetry surface areas (1 m[sup 2]/g). This indicated that micropores (d[sub MIP]<2 nm) were present in the alumina, since they were large enough for nitrogen gas molecules to enter, but too small for mercury to enter. As a result they would be too small for significant diffusion rates of residuum molecules. In earlier work, the calcining temperature was fixed at 500[degrees]C. In the current work, variations in both calcining temperature and calcining time were used in an attempt to convert some of the micropores into mesopores. 12 refs., 2 figs., 1 tab.

  10. Large-Scale Disasters

    NASA Astrophysics Data System (ADS)

    Gad-El-Hak, Mohamed

    "Extreme" events - including climatic events, such as hurricanes, tornadoes, and drought - can cause massive disruption to society, including large death tolls and property damage in the billions of dollars. Events in recent years have shown the importance of being prepared and that countries need to work together to help alleviate the resulting pain and suffering. This volume presents a review of the broad research field of large-scale disasters. It establishes a common framework for predicting, controlling and managing both manmade and natural disasters. There is a particular focus on events caused by weather and climate change. Other topics include air pollution, tsunamis, disaster modeling, the use of remote sensing and the logistics of disaster management. It will appeal to scientists, engineers, first responders and health-care professionals, in addition to graduate students and researchers who have an interest in the prediction, prevention or mitigation of large-scale disasters.

  11. Large TV display system

    NASA Technical Reports Server (NTRS)

    Liu, Hua-Kuang (Inventor)

    1986-01-01

    A relatively small and low cost system is provided for projecting a large and bright television image onto a screen. A miniature liquid crystal array is driven by video circuitry to produce a pattern of transparencies in the array corresponding to a television image. Light is directed against the rear surface of the array to illuminate it, while a projection lens lies in front of the array to project the image of the array onto a large screen. Grid lines in the liquid crystal array are eliminated by a spacial filter which comprises a negative of the Fourier transform of the grid.

  12. Large gauged Q balls

    NASA Astrophysics Data System (ADS)

    Anagnostopoulos, K. N.; Axenides, M.; Floratos, E. G.; Tetradis, N.

    2001-12-01

    We study Q balls associated with local U(1) symmetries. Such Q balls are expected to become unstable for large values of their charge because of the repulsion mediated by the gauge force. We consider the possibility that the repulsion is eliminated through the presence in the interior of the Q ball of fermions with charge opposite to that of the scalar condensate. Another possibility is that two scalar condensates of opposite charge form in the interior. We demonstrate that both these scenarios can lead to the existence of classically stable, large, gauged Q balls. We present numerical solutions, as well as an analytical treatment of the ``thin-wall'' limit.

  13. Teaching Very Large Classes

    ERIC Educational Resources Information Center

    DeRogatis, Amy; Honerkamp, Kenneth; McDaniel, Justin; Medine, Carolyn; Nyitray, Vivian-Lee; Pearson, Thomas

    2014-01-01

    The editor of "Teaching Theology and Religion" facilitated this reflective conversation with five teachers who have extensive experience and success teaching extremely large classes (150 students or more). In the course of the conversation these professors exchange and analyze the effectiveness of several active learning strategies they…

  14. Large N Cosmology

    NASA Astrophysics Data System (ADS)

    Hawking, S. W.

    2001-09-01

    The large N approximation should hold in cosmology even at the origin of the universe. I use ADS-CFT to calculate the effective action and obtain a cosmological model in which inflation is driven by the trace anomaly. Despite having ghosts, this model can agree with observations.

  15. Developing Large CAI Packages.

    ERIC Educational Resources Information Center

    Reed, Mary Jac M.; Smith, Lynn H.

    1983-01-01

    When developing large computer-assisted instructional (CAI) courseware packages, it is suggested that there be more attentive planning to the overall package design before actual lesson development is begun. This process has been simplified by modifying the systems approach used to develop single CAI lessons, followed by planning for the…

  16. Risks of Large Portfolios

    PubMed Central

    Fan, Jianqing; Liao, Yuan; Shi, Xiaofeng

    2014-01-01

    The risk of a large portfolio is often estimated by substituting a good estimator of the volatility matrix. However, the accuracy of such a risk estimator is largely unknown. We study factor-based risk estimators under a large amount of assets, and introduce a high-confidence level upper bound (H-CLUB) to assess the estimation. The H-CLUB is constructed using the confidence interval of risk estimators with either known or unknown factors. We derive the limiting distribution of the estimated risks in high dimensionality. We find that when the dimension is large, the factor-based risk estimators have the same asymptotic variance no matter whether the factors are known or not, which is slightly smaller than that of the sample covariance-based estimator. Numerically, H-CLUB outperforms the traditional crude bounds, and provides an insightful risk assessment. In addition, our simulated results quantify the relative error in the risk estimation, which is usually negligible using 3-month daily data. PMID:26195851

  17. Teaching Large Evening Classes

    ERIC Educational Resources Information Center

    Wambuguh, Oscar

    2008-01-01

    High enrollments, conflicting student work schedules, and the sheer convenience of once-a-week classes are pushing many colleges to schedule evening courses. Held from 6 to 9 pm or 7 to 10 pm, these classes are typically packed, sometimes with more than 150 students in a large lecture theater. How can faculty effectively teach, control, or even…

  18. Death Writ Large

    ERIC Educational Resources Information Center

    Kastenbaum, Robert

    2004-01-01

    Mainstream thanatology has devoted its efforts to improving the understanding, care, and social integration of people who are confronted with life-threatening illness or bereavement. This article suggests that it might now be time to expand the scope and mission to include large-scale death and death that occurs through complex and multi-domain…

  19. LARGE BUILDING HVAC SIMULATION

    EPA Science Inventory

    The report discusses the monitoring and collection of data relating to indoor pressures and radon concentrations under several test conditions in a large school building in Bartow, Florida. The Florida Solar Energy Center (FSEC) used an integrated computational software, FSEC 3.0...

  20. Estimating Large Numbers

    ERIC Educational Resources Information Center

    Landy, David; Silbert, Noah; Goldin, Aleah

    2013-01-01

    Despite their importance in public discourse, numbers in the range of 1 million to 1 trillion are notoriously difficult to understand. We examine magnitude estimation by adult Americans when placing large numbers on a number line and when qualitatively evaluating descriptions of imaginary geopolitical scenarios. Prior theoretical conceptions…

  1. Launching large antennas

    NASA Astrophysics Data System (ADS)

    Brandli, H. W.

    1983-09-01

    Large antennas will provide communication to rural and remote areas in times of need. This is seen as facilitating the work of law enforcement agencies. All mobile radio communications will enjoy advantages in distances covered and information relayed owing to the large number of beams possible from super radio transmitters in space. If the antennas are placed in low-earth orbit, advantages will be realized in the remote sensing of the earth's resources. It is pointed out that with umbrella or bicyclelike antennas turned outward toward space, the universe could be scouted for signals from intelligent life. Various concepts that have been put forward by U.S. companies are described. These include the radial rib, wrap rib, and parabolic erectable truss designs. Others are the mesh hoop column collapsable umbrella made of gold and molybdenum and the maypole design.

  2. Coherent large telescopes

    NASA Astrophysics Data System (ADS)

    Nelson, J. E.

    Present ground-based telescopes are compared with those of the future. The inherent limitations of ground-based telescopes are reviewed, and existing telescopes and their evolution are briefly surveyed in order to see the trends that led to the present period of innovative telescope design. The major telescope types and the critical design factors that must be considered in designing large telescopes for the future are reviewed, emphasizing economicality. As an example, the Ten Meter Telescope project at the University of California is discussed in detail, including the telescope buildings, domes, and apertures, the telescope moving weights, the image quality, and the equipment. Finally, a brief review of current work in progress on large telescopes is given.

  3. Hulls for Large Seaplanes

    NASA Technical Reports Server (NTRS)

    Magaldi, Giulio

    1925-01-01

    In reality, the principle of similitude is not applicable to the hulls, the designing of which increases in difficulty with increasing size of the seaplanes. In order to formulate, at least in a general way, the basic principles of calculation, we must first summarize the essential characteristics of a hull with reference to its gradual enlargement. In this study, we will disregard hulls with wing stubs, as being inapplicable to large seaplanes.

  4. The Large Area Telescope

    SciTech Connect

    Michelson, Peter F.; /KIPAC, Menlo Park /Stanford U., HEPL

    2007-11-13

    The Large Area Telescope (LAT), one of two instruments on the Gamma-ray Large Area Space Telescope (GLAST) mission, is an imaging, wide field-of-view, high-energy pair-conversion telescope, covering the energy range from {approx}20 MeV to more than 300 GeV. The LAT is being built by an international collaboration with contributions from space agencies, high-energy particle physics institutes, and universities in France, Italy, Japan, Sweden, and the United States. The scientific objectives the LAT will address include resolving the high-energy gamma-ray sky and determining the nature of the unidentified gamma-ray sources and the origin of the apparently isotropic diffuse emission observed by EGRET; understanding the mechanisms of particle acceleration in celestial sources, including active galactic nuclei, pulsars, and supernovae remnants; studying the high-energy behavior of gamma-ray bursts and transients; using high-energy gamma-rays to probe the early universe to z {ge} 6; and probing the nature of dark matter. The components of the LAT include a precision silicon-strip detector tracker and a CsI(Tl) calorimeter, a segmented anticoincidence shield that covers the tracker array, and a programmable trigger and data acquisition system. The calorimeter's depth and segmentation enable the high-energy reach of the LAT and contribute significantly to background rejection. The aspect ratio of the tracker (height/width) is 0.4, allowing a large field-of-view and ensuring that nearly all pair-conversion showers initiated in the tracker will pass into the calorimeter for energy measurement. This paper includes a description of each of these LAT subsystems as well as a summary of the overall performance of the telescope.

  5. Large area LED package

    NASA Astrophysics Data System (ADS)

    Goullon, L.; Jordan, R.; Braun, T.; Bauer, J.; Becker, F.; Hutter, M.; Schneider-Ramelow, M.; Lang, K.-D.

    2015-03-01

    Solid state lighting using LED-dies is a rapidly growing market. LED-dies with the needed increasing luminous flux per chip area produce a lot of heat. Therefore an appropriate thermal management is required for general lighting with LEDdies. One way to avoid overheating and shorter lifetime is the use of many small LED-dies on a large area heat sink (down to 70 μm edge length), so that heat can spread into a large area while at the same time light also appears on a larger area. The handling with such small LED-dies is very difficult because they are too small to be picked with common equipment. Therefore a new concept called collective transfer bonding using a temporary carrier chip was developed. A further benefit of this new technology is the high precision assembly as well as the plane parallel assembly of the LED-dies which is necessary for wire bonding. It has been shown that hundred functional LED-dies were transferred and soldered at the same time. After the assembly a cost effective established PCB-technology was applied to produce a large-area light source consisting of many small LED-dies and electrically connected on a PCB-substrate. The top contacts of the LED-dies were realized by laminating an adhesive copper sheet followed by LDI structuring as known from PCB-via-technology. This assembly can be completed by adding converting and light forming optical elements. In summary two technologies based on standard SMD and PCB technology have been developed for panel level LED packaging up to 610x 457 mm2 area size.

  6. Gyrokinetic large eddy simulations

    SciTech Connect

    Morel, P.; Navarro, A. Banon; Albrecht-Marc, M.; Carati, D.; Merz, F.; Goerler, T.; Jenko, F.

    2011-07-15

    The large eddy simulation approach is adapted to the study of plasma microturbulence in a fully three-dimensional gyrokinetic system. Ion temperature gradient driven turbulence is studied with the GENE code for both a standard resolution and a reduced resolution with a model for the sub-grid scale turbulence. A simple dissipative model for representing the effect of the sub-grid scales on the resolved scales is proposed and tested. Once calibrated, the model appears to be able to reproduce most of the features of the free energy spectra for various values of the ion temperature gradient.

  7. Large space structures testing

    NASA Technical Reports Server (NTRS)

    Waites, Henry; Worley, H. Eugene

    1987-01-01

    There is considerable interest in the development of testing concepts and facilities that accurately simulate the pathologies believed to exist in future spacecraft. Both the Government and Industry have participated in the development of facilites over the past several years. The progress and problems associated with the development of the Large Space Structure Test Facility at the Marshall Flight Center are presented. This facility was in existence for a number of years and its utilization has run the gamut from total in-house involvement, third party contractor testing, to the mutual participation of other Government Agencies in joint endeavors.

  8. Large, Bright Wind Ripples

    NASA Technical Reports Server (NTRS)

    2003-01-01

    MGS MOC Release No. MOC2-397, 20 June 2003

    This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows large, relatively bright ripples of windblown sediment in the Sinus Sabaeus region south of Schiaparelli Basin. The surrounding substrate is thickly mantled by very dark material, possibly windblown silt that settled out of the atmosphere. The picture is located near 7.1oS, 343.7oW. Sunlight illuminates the scene from the left.

  9. Large Windblown Ripples

    NASA Technical Reports Server (NTRS)

    2003-01-01

    MGS MOC Release No. MOC2-519, 20 October 2003

    This April 2003 Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) high resolution image shows a depression in the martian southern cratered highlands near 1.3oS, 244.3oW. The floor of the depression and some nearby craters are covered by large windblown ripples or small sand dunes. This image of ancient martian terrain covers an area 3 km (1.9 mi) across and is illuminated by sunlight from the upper left.

  10. Large Spectral Library Problem

    SciTech Connect

    Chilton, Lawrence K.; Walsh, Stephen J.

    2008-10-03

    Hyperspectral imaging produces a spectrum or vector at each image pixel. These spectra can be used to identify materials present in the image. In some cases, spectral libraries representing atmospheric chemicals or ground materials are available. The challenge is to determine if any of the library chemicals or materials exist in the hyperspectral image. The number of spectra in these libraries can be very large, far exceeding the number of spectral channels collected in the ¯eld. Suppose an image pixel contains a mixture of p spectra from the library. Is it possible to uniquely identify these p spectra? We address this question in this paper and refer to it as the Large Spectral Library (LSL) problem. We show how to determine if unique identi¯cation is possible for any given library. We also show that if p is small compared to the number of spectral channels, it is very likely that unique identi¯cation is possible. We show that unique identi¯cation becomes less likely as p increases.

  11. Infinitely Large New Dimensions

    SciTech Connect

    Arkani-Hamed, Nima; Dimopoulos, Savas; Dvali, Gia; Kaloper, Nemanja

    1999-07-29

    We construct intersecting brane configurations in Anti-de-Sitter space localizing gravity to the intersection region, with any number n of extra dimensions. This allows us to construct two kinds of theories with infinitely large new dimensions, TeV scale quantum gravity and sub-millimeter deviations from Newton's Law. The effective 4D Planck scale M{sub Pl} is determined in terms of the fundamental Planck scale M{sub *} and the AdS radius of curvature L via the familiar relation M{sub Pl}{sup 2} {approx} M{sub *}{sup 2+n} L{sup n}; L acts as an effective radius of compactification for gravity on the intersection. Taking M{sub *} {approx} TeV and L {approx} sub-mm reproduces the phenomenology of theories with large extra dimensions. Alternately, taking M{sub *} {approx} L{sup -1} {approx} M{sub Pl}, and placing our 3-brane a distance {approx} 100M{sub Pl}{sup -1} away from the intersection gives us a theory with an exponential determination of the Weak/Planck hierarchy.

  12. Large Particle Titanate Sorbents

    SciTech Connect

    Taylor-Pashow, K.

    2015-10-08

    This research project was aimed at developing a synthesis technique for producing large particle size monosodium titanate (MST) to benefit high level waste (HLW) processing at the Savannah River Site (SRS). Two applications were targeted, first increasing the size of the powdered MST used in batch contact processing to improve the filtration performance of the material, and second preparing a form of MST suitable for deployment in a column configuration. Increasing the particle size should lead to improvements in filtration flux, and decreased frequency of filter cleaning leading to improved throughput. Deployment of MST in a column configuration would allow for movement from a batch process to a more continuous process. Modifications to the typical MST synthesis led to an increase in the average particle size. Filtration testing on dead-end filters showed improved filtration rates with the larger particle material; however, no improvement in filtration rate was realized on a crossflow filter. In order to produce materials suitable for column deployment several approaches were examined. First, attempts were made to coat zirconium oxide microspheres (196 µm) with a layer of MST. This proved largely unsuccessful. An alternate approach was then taken synthesizing a porous monolith of MST which could be used as a column. Several parameters were tested, and conditions were found that were able to produce a continuous structure versus an agglomeration of particles. This monolith material showed Sr uptake comparable to that of previously evaluated samples of engineered MST in batch contact testing.

  13. Large furlable antenna study

    NASA Technical Reports Server (NTRS)

    Campbell, G. K. C.

    1975-01-01

    The parametric study of the performance of large furlable antennas is described and the availability of various size antennas is discussed. Three types of unfurlable reflector designs are considered: the wrapped rib, the polyconic, and the maypole. On the basis of these approaches, a space shuttle launch capability, and state-of-the-art materials, it is possible to design unfurlable reflectors as large as 130 feet (40 meters) in diameter to operate at 10 GHz and 600 feet (183 meters) in diameter at 0.5 GHz. These figures can be increased if very low thermal coefficient of expansion materials can be developed over the next 2-5 years. It is recommended that a special effort be made to develop light weight materials that would provide nearly zero thermal coefficient of expansion and good thermal conductivity within the next 10 years. A conservative prediction of the kinds of unfurlable spacecraft antennas that will be available by 1985 with orbital performance predicted on the basis of test data and with developed manufacturing processes is summarized.

  14. Synchronizing large systolic arrays

    SciTech Connect

    Fisher, A.L.; Kung, H.T.

    1982-04-01

    Parallel computing structures consist of many processors operating simultaneously. If a concurrent structure is regular, as in the case of systolic array, it may be convenient to think of all processors as operating in lock step. Totally synchronized systems controlled by central clocks are difficult to implement because of the inevitable problem of clock skews and delays. An alternate means of enforcing necessary synchronization is the use of self-timed, asynchronous schemes, at the cost of increased design complexity and hardware cost. Realizing that different circumstances call for different synchronization methods, this paper provides a spectrum of synchronization models; based on the assumptions made for each model, theoretical lower bounds on clock skew are derived, and appropriate or best-possible synchronization schemes for systolic arrays are proposed. This paper represents a first step towards a systematic study of synchronization problems for large systolic arrays.

  15. Large area plasma source

    NASA Technical Reports Server (NTRS)

    Foster, John (Inventor); Patterson, Michael (Inventor)

    2008-01-01

    An all permanent magnet Electron Cyclotron Resonance, large diameter (e.g., 40 cm) plasma source suitable for ion/plasma processing or electric propulsion, is capable of producing uniform ion current densities at its exit plane at very low power (e.g., below 200 W), and is electrodeless to avoid sputtering or contamination issues. Microwave input power is efficiently coupled with an ionizing gas without using a dielectric microwave window and without developing a throat plasma by providing a ferromagnetic cylindrical chamber wall with a conical end narrowing to an axial entrance hole for microwaves supplied on-axis from an open-ended waveguide. Permanent magnet rings are attached inside the wall with alternating polarities against the wall. An entrance magnet ring surrounding the entrance hole has a ferromagnetic pole piece that extends into the chamber from the entrance hole to a continuing second face that extends radially across an inner pole of the entrance magnet ring.

  16. Contrasting Large Solar Events

    NASA Astrophysics Data System (ADS)

    Lanzerotti, Louis J.

    2010-10-01

    After an unusually long solar minimum, solar cycle 24 is slowly beginning. A large coronal mass ejection (CME) from sunspot 1092 occurred on 1 August 2010, with effects reaching Earth on 3 August and 4 August, nearly 38 years to the day after the huge solar event of 4 August 1972. The prior event, which those of us engaged in space research at the time remember well, recorded some of the highest intensities of solar particles and rapid changes of the geomagnetic field measured to date. What can we learn from the comparisons of these two events, other than their essentially coincident dates? One lesson I took away from reading press coverage and Web reports of the August 2010 event is that the scientific community and the press are much more aware than they were nearly 4 decades ago that solar events can wreak havoc on space-based technologies.

  17. Large Binocular Telescope Project

    NASA Astrophysics Data System (ADS)

    Hill, John M.; Salinari, Piero

    1998-08-01

    The Large Binocular Telescope (LBT) Project is a collaboration between institutions in Arizona, Germany, Italy, and Ohio. With the addition of the partners from Ohio State and Germany in February 1997, the Large Binocular Telescope Corporation has the funding required to build the full telescope populated with both 8.4 meter optical trans. The first of two 8.4 meter borosilicate honeycomb primary mirrors for LBT was cast at the Steward Observatory Mirror Lab in 1997. The baseline optical configuration of LBT includes adaptive infrared secondaries of a Gregorian design. The F/15 secondaries are undersized to provide a low thermal background focal plane. The interferometric focus combining the light from the two 8.4 meter primaries will reimage the two folded Gregorian focal planes to three central locations. The telescope elevation structure accommodates swing arms which allow rapid interchange of the various secondary and tertiary mirrors. Maximum stiffness and minimal thermal disturbance were important drivers for the design of the telescope in order to provide the best possible images for interferometric observations. The telescope structure accommodates installation of a vacuum bell jar for aluminizing the primary mirrors in-situ on the telescope. The detailed design of the telescope structure was completed in 1997 by ADS Italia (Lecco) and European Industrial Engineering (Mestre). A series of contracts for the fabrication and machining of the telescope structure had been placed at the end of 1997. The final enclosure design was completed at M3 Engineering & Technology (Tucson), EIE and ADS Italia. During 1997, the telescope pier and the concrete ring wall for the rotating enclosure were completed along with the steel structure of the fixed portion of the enclosure. The erection of the steel structure for the rotating portion of the enclosure will begin in the Spring of 1998.

  18. The large binocular telescope.

    PubMed

    Hill, John M

    2010-06-01

    The Large Binocular Telescope (LBT) Observatory is a collaboration among institutions in Arizona, Germany, Italy, Indiana, Minnesota, Ohio, and Virginia. The telescope on Mount Graham in Southeastern Arizona uses two 8.4 m diameter primary mirrors mounted side by side. A unique feature of the LBT is that the light from the two Gregorian telescope sides can be combined to produce phased-array imaging of an extended field. This cophased imaging along with adaptive optics gives the telescope the diffraction-limited resolution of a 22.65 m aperture and a collecting area equivalent to an 11.8 m circular aperture. This paper describes the design, construction, and commissioning of this unique telescope. We report some sample astronomical results with the prime focus cameras. We comment on some of the technical challenges and solutions. The telescope uses two F/15 adaptive secondaries to correct atmospheric turbulence. The first of these adaptive mirrors has completed final system testing in Firenze, Italy, and is planned to be at the telescope by Spring 2010. PMID:20517352

  19. Large area Czochralski silicon

    NASA Technical Reports Server (NTRS)

    Rea, S. N.; Gleim, P. S.

    1977-01-01

    The overall cost effectiveness of the Czochralski process for producing large-area silicon was determined. The feasibility of growing several 12 cm diameter crystals sequentially at 12 cm/h during a furnace run and the subsequent slicing of the ingot using a multiblade slurry saw were investigated. The goal of the wafering process was a slice thickness of 0.25 mm with minimal kerf. A slice + kerf of 0.56 mm was achieved on 12 cm crystal using both 400 grit B4C and SiC abrasive slurries. Crystal growth experiments were performed at 12 cm diameter in a commercially available puller with both 10 and 12 kg melts. Several modifications to the puller hoz zone were required to achieve stable crystal growth over the entire crystal length and to prevent crystallinity loss a few centimeters down the crystal. The maximum practical growth rate for 12 cm crystal in this puller design was 10 cm/h, with 12 to 14 cm/h being the absolute maximum range at which melt freeze occurred.

  20. Large forging manufacturing process

    DOEpatents

    Thamboo, Samuel V.; Yang, Ling

    2002-01-01

    A process for forging large components of Alloy 718 material so that the components do not exhibit abnormal grain growth includes the steps of: a) providing a billet with an average grain size between ASTM 0 and ASTM 3; b) heating the billet to a temperature of between 1750.degree. F. and 1800.degree. F.; c) upsetting the billet to obtain a component part with a minimum strain of 0.125 in at least selected areas of the part; d) reheating the component part to a temperature between 1750.degree. F. and 1800.degree. F.; e) upsetting the component part to a final configuration such that said selected areas receive no strains between 0.01 and 0.125; f) solution treating the component part at a temperature of between 1725.degree. F. and 1750.degree. F.; and g) aging the component part over predetermined times at different temperatures. A modified process achieves abnormal grain growth in selected areas of a component where desirable.

  1. Large scale tracking algorithms.

    SciTech Connect

    Hansen, Ross L.; Love, Joshua Alan; Melgaard, David Kennett; Karelitz, David B.; Pitts, Todd Alan; Zollweg, Joshua David; Anderson, Dylan Z.; Nandy, Prabal; Whitlow, Gary L.; Bender, Daniel A.; Byrne, Raymond Harry

    2015-01-01

    Low signal-to-noise data processing algorithms for improved detection, tracking, discrimination and situational threat assessment are a key research challenge. As sensor technologies progress, the number of pixels will increase signi cantly. This will result in increased resolution, which could improve object discrimination, but unfortunately, will also result in a significant increase in the number of potential targets to track. Many tracking techniques, like multi-hypothesis trackers, suffer from a combinatorial explosion as the number of potential targets increase. As the resolution increases, the phenomenology applied towards detection algorithms also changes. For low resolution sensors, "blob" tracking is the norm. For higher resolution data, additional information may be employed in the detection and classfication steps. The most challenging scenarios are those where the targets cannot be fully resolved, yet must be tracked and distinguished for neighboring closely spaced objects. Tracking vehicles in an urban environment is an example of such a challenging scenario. This report evaluates several potential tracking algorithms for large-scale tracking in an urban environment.

  2. Stability of large systems

    NASA Astrophysics Data System (ADS)

    Hastings, Harold

    2007-03-01

    We address a long-standing dilemma concerning stability of large systems. MacArthur (1955) and Hutchinson (1959) argued that more ``complex'' natural systems tended to be more stable than less complex systems based upon energy flow. May (1972) argued the opposite, using random matrix models; see Cohen and Newman (1984, 1985), Bai and Yin (1986). We show that in some sense both are right: under reasonable scaling assumptions on interaction strength, Lyapunov stability increases but structural stability decreases as complexity is increased (c.f. Harrison, 1979; Hastings, 1984). We apply this result to a variety of network systems. References: Bai, Z.D. & Yin, Y.Q. 1986. Probab. Th. Rel. Fields 73, 555. Cohen, J.E., & Newman, C.M. 1984. Annals Probab. 12, 283; 1985. Theoret. Biol. 113, 153. Harrison, G.W. 1979. Amer. Natur. 113, 659. Hastings, H.M. 1984. BioSystems 17, 171. Hastings, H.M., Juhasz, F., & Schreiber, M. 1992. .Proc. Royal Soc., Ser. B. 249, 223. Hutchinson, G.E. 1959. Amer. Natur. 93, 145, MacArthur, R. H. 1955. Ecology 35, 533, May, R.M. 1972. Nature 238, 413.

  3. The Large Millimeter Telescope

    NASA Astrophysics Data System (ADS)

    Hughes, D. H.; Schloerb, F. P.; LMT Project Team

    2009-05-01

    This paper, presented on behalf of the Large Millimeter Telescope (LMT) project team, describes the status and near-term plans for the telescope and its initial instrumentation. The LMT is a bi-national collaboration between México and the USA, led by the Instituto Nacional de Astrofísica, Óptica y Electrónica (INAOE) and the University of Massachusetts at Amherst, to construct, commission and operate a 50 m diameter millimeter-wave radio telescope. Construction activities are nearly complete at the LMT site, at an altitude of ˜ 4600 m on the summit of Sierra Negra, an extinct volcano in the Mexican state of Puebla. Full movement of the telescope, under computer control in both azimuth and elevation, has been achieved. First-light at centimeter wavelengths on astronomical sources was obtained in November 2006. Installation of precision surface segments for millimeter-wave operation is underway, with the inner 32 m diameter of the surface now complete and ready to be used to obtain first-light at millimeter wavelengths in 2008. Installation of the remainder of the reflector will continue during the next year and be completed in 2009 for final commissioning of the antenna. The full LMT antenna, outfitted with its initial complement of scientific instruments, will be a world-leading scientific research facility for millimeter-wave astronomy.

  4. The Large Millimeter Telescope

    NASA Astrophysics Data System (ADS)

    Schloerb, F. Peter

    2008-07-01

    This paper, presented on behalf of the Large Millimeter Telescope (LMT) project team, describes the status and near-term plans for the telescope and its initial instrumentation. The LMT is a bi-national collaboration between Mexico and the USA, led by the Instituto Nacional de Astrofísica, Optica y Electronica (INAOE) and the University of Massachusetts at Amherst, to construct, commission and operate a 50m-diameter millimeter-wave radio telescope. Construction activities are nearly complete at the 4600m LMT site on the summit of Sierra Negra, an extinct volcano in the Mexican state of Puebla. Full movement of the telescope, under computer control in both azimuth and elevation, has been achieved. First-light at centimeter wavelengths on astronomical sources was obtained in November 2006. Installation of precision surface segments for millimeter-wave operation is underway, with the inner 32m-diameter of the surface now complete and ready to be used to obtain first light at millimeter wavelengths in 2008. Installation of the remainder of the reflector will continue during the next year and be completed in 2009 for final commissioning of the antenna. The full LMT antenna, outfitted with its initial complement of scientific instruments, will be a world-leading scientific research facility for millimeter-wave astronomy.

  5. Large scale traffic simulations

    SciTech Connect

    Nagel, K.; Barrett, C.L.; Rickert, M.

    1997-04-01

    Large scale microscopic (i.e. vehicle-based) traffic simulations pose high demands on computational speed in at least two application areas: (i) real-time traffic forecasting, and (ii) long-term planning applications (where repeated {open_quotes}looping{close_quotes} between the microsimulation and the simulated planning of individual person`s behavior is necessary). As a rough number, a real-time simulation of an area such as Los Angeles (ca. 1 million travellers) will need a computational speed of much higher than 1 million {open_quotes}particle{close_quotes} (= vehicle) updates per second. This paper reviews how this problem is approached in different projects and how these approaches are dependent both on the specific questions and on the prospective user community. The approaches reach from highly parallel and vectorizable, single-bit implementations on parallel supercomputers for Statistical Physics questions, via more realistic implementations on coupled workstations, to more complicated driving dynamics implemented again on parallel supercomputers. 45 refs., 9 figs., 1 tab.

  6. Large Deployable Reflectarray Antenna

    NASA Technical Reports Server (NTRS)

    Fang, Houfei; Huang, John; Lou, Michael

    2006-01-01

    A report discusses a 7-meter-diameter reflectarray antenna that has been conceived in a continuing effort to develop large reflectarray antennas to be deployed in outer space. Major underlying concepts were reported in three prior NASA Tech Briefs articles: "Inflatable Reflectarray Antennas" (NPO-20433), Vol. 23, No. 10 (October 1999), page 50; "Tape-Spring Reinforcements for Inflatable Structural Tubes" (NPO-20615), Vol. 24, No. 7 (July 2000), page 58; and "Self-Inflatable/Self-Rigidizable Reflectarray Antenna" (NPO-30662), Vol. 28, No. 1 (January 2004), page 61. Like previous antennas in the series, the antenna now proposed would include a reflectarray membrane stretched flat on a frame of multiple inflatable booms. The membrane and booms would be rolled up and folded for compact stowage during transport. Deployment in outer space would be effected by inflating the booms to unroll and then to unfold the membrane, thereby stretching the membrane out flat to its full size. The membrane would achieve the flatness for a Ka-band application. The report gives considerable emphasis to designing the booms to rigidify themselves upon deployment: for this purpose, the booms could be made as spring-tape-reinforced aluminum laminate tubes like those described in two of the cited prior articles.

  7. Large Format Radiographic Imaging

    SciTech Connect

    J. S. Rohrer; Lacey Stewart; M. D. Wilke; N. S. King; S. A Baker; Wilfred Lewis

    1999-08-01

    Radiographic imaging continues to be a key diagnostic in many areas at Los Alamos National Laboratory (LANL). Radiographic recording systems have taken on many form, from high repetition-rate, gated systems to film recording and storage phosphors. Some systems are designed for synchronization to an accelerator while others may be single shot or may record a frame sequence in a dynamic radiography experiment. While film recording remains a reliable standby in the radiographic community, there is growing interest in investigating electronic recording for many applications. The advantages of real time access to remote data acquisition are highly attractive. Cooled CCD camera systems are capable of providing greater sensitivity with improved signal-to-noise ratio. This paper begins with a review of performance characteristics of the Bechtel Nevada large format imaging system, a gated system capable of viewing scintillators up to 300 mm in diameter. We then examine configuration alternatives in lens coupled and fiber optically coupled electro-optical recording systems. Areas of investigation include tradeoffs between fiber optic and lens coupling, methods of image magnification, and spectral matching from scintillator to CCD camera. Key performance features discussed include field of view, resolution, sensitivity, dynamic range, and system noise characteristics.

  8. [Large granular lymphocyte leukemia].

    PubMed

    Lazaro, Estibaliz; Caubet, Olivier; Menard, Fanny; Pellegrin, Jean-Luc; Viallard, Jean-François

    2007-11-01

    Large granular lymphocyte (LGL) leukemia is a clonal proliferation of cytotoxic cells, either CD3(+) (T-cell) or CD3(-) (natural killer, or NK). Both subtypes can manifest as indolent or aggressive disorders. T-LGL leukemia is associated with cytopenias and autoimmune diseases and most often has an indolent course and good prognosis. Rheumatoid arthritis and Felty syndrome are frequent. NK-LGL leukemias can be more aggressive. LGL expansion is currently hypothesized to be a virus (Ebstein Barr or human T-cell leukemia viruses) antigen-driven T-cell response that involves disruption of apoptosis. The diagnosis of T-LGL is suggested by flow cytometry and confirmed by T-cell receptor gene rearrangement studies. Clonality is difficult to determine in NK-LGL but use of monoclonal antibodies specific for killer cell immunoglobulin-like receptor (KIR) has improved this process. Treatment is required when T-LGL leukemia is associated with recurrent infections secondary to chronic neutropenia. Long-lasting remission can be obtained with immunosuppressive treatments such as methotrexate, cyclophosphamide, and cyclosporine A. NK-LGL leukemias may be more aggressive and refractory to conventional therapy. PMID:17596907

  9. Very Large Scale Optimization

    NASA Technical Reports Server (NTRS)

    Vanderplaats, Garrett; Townsend, James C. (Technical Monitor)

    2002-01-01

    The purpose of this research under the NASA Small Business Innovative Research program was to develop algorithms and associated software to solve very large nonlinear, constrained optimization tasks. Key issues included efficiency, reliability, memory, and gradient calculation requirements. This report describes the general optimization problem, ten candidate methods, and detailed evaluations of four candidates. The algorithm chosen for final development is a modern recreation of a 1960s external penalty function method that uses very limited computer memory and computational time. Although of lower efficiency, the new method can solve problems orders of magnitude larger than current methods. The resulting BIGDOT software has been demonstrated on problems with 50,000 variables and about 50,000 active constraints. For unconstrained optimization, it has solved a problem in excess of 135,000 variables. The method includes a technique for solving discrete variable problems that finds a "good" design, although a theoretical optimum cannot be guaranteed. It is very scalable in that the number of function and gradient evaluations does not change significantly with increased problem size. Test cases are provided to demonstrate the efficiency and reliability of the methods and software.

  10. Blood vessel growth blocker may treat AIDS-related Kaposi’s sarcoma

    Cancer.gov

    Patients with an AIDS-associated cancer, Kaposi's sarcoma (KS), showed improvement after receiving the combination of bevacizumab, a cancer drug that blocks the growth of new blood vessels, and highly active antiretroviral therapy (HAART).

  11. The influence of mental health problems on AIDS-related risk behaviors in young adults.

    PubMed

    Stiffman, A R; Doré, P; Earls, F; Cunningham, R

    1992-05-01

    This paper explores how symptoms of mental health problems influence acquired immune deficiency syndrome-related risk behaviors, and how changes in those symptoms relate to risk behaviors engaged in by young adults. Repeated interviews with 602 youths since 1984 provide a history of change in behaviors. Mental health symptoms during adolescence (alcohol/drug [r = .28]; conduct disorder [r = .27]; depression [r = .16]; suicide [r = .14]; anxiety [r = .16]; and posttraumatic stress [r = .09]) are associated with higher numbers of risk behaviors (specifically, prostitution, use of intravenous drugs, and choice of a high-risk sex partner) during young adulthood. Changes in mental health symptoms between adolescence and young adulthood are related to the number of risk behaviors engaged in by young adulthood (total number of symptoms [B = .10], alcohol/drug abuse or dependence [B = .34], depression [B = .20], suicidality [B = .35], anxiety [B = .13], and posttraumatic stress [B = .14]). Changes in symptoms of mental health problems are associated specifically with those risk behaviors that are initiated primarily in young adulthood: intravenous drug use, prostitution, and choice of risky partners. The findings show that prevention and treatment of mental health problems are important components of preventive interventions for human immunodeficiency virus infection in high-risk teens and young adults. PMID:1583474

  12. Circulating serum free light chains as predictive markers of AIDS-related lymphoma.

    PubMed

    Landgren, Ola; Goedert, James J; Rabkin, Charles S; Wilson, Wyndham H; Dunleavy, Kieron; Kyle, Robert A; Katzmann, Jerry A; Rajkumar, S Vincent; Engels, Eric A

    2010-02-10

    PURPOSE HIV-infected persons have an elevated risk of developing non-Hodgkin's lymphoma (NHL); this risk remains increased in the era of effective HIV therapy. We evaluated serum immunoglobulin (Ig) proteins as predictors of NHL risk among HIV-infected individuals. PATIENTS AND METHODS By using three cohorts of HIV-infected persons (from 1982 to 2005), we identified 66 individuals who developed NHL and 225 matched (by cohort, sex, ethnicity, age, and CD4 count), HIV-infected, lymphoma-free controls who had available stored prediagnostic blood samples. Serum/plasma samples obtained 0 to 2 years and 2 to 5 years before diagnosis/selection were assayed for IgG, IgM, and IgA levels; monoclonal (M) Igs; and kappa and lambda free light chain (FLC) levels. Patients and matched controls were compared by using conditional logistic regression. Results The kappa and lambda FLCs were both significantly higher in patients (eg, in 2- to 5-year window: median kappa, 4.24 v 3.43 mg/dL; median lambda, 4.04 v 3.09 mg/dL) and strongly predicted NHL in a dose-response manner up to 2 to 5 years before diagnosis/selection (eg, NHL risk 3.76-fold higher with kappa concentration at least 2.00 times the upper limit of normal, and 8.13-fold higher with lambda concentration at least 2.00 times the upper limit of normal compared with normal levels). In contrast, IgG, IgM, and IgA levels were similar in patients and controls. M proteins were detected in only two patients with NHL (3%) and in nine controls (4%), and they were not significantly associated with NHL risk. CONCLUSION Elevated FLCs may represent sensitive markers of polyclonal B-cell activation and dysfunction and could be useful for identifying HIV-infected persons at increased NHL risk. PMID:20048176

  13. The Impact of Residency Training on Physicians' AIDS-Related Treatment Practices: A Longitudinal Panel Study.

    ERIC Educational Resources Information Center

    Yedidia, Michael J.; Berry, Carolyn A.

    1999-01-01

    Study of 394 physicians graduating in 1989 from six New York medical schools found that certain residency-training factors had sustained effects on physician behavior in caring for AIDS (acquired immune deficiency syndrome) patients, but not on the number of patients treated. Determinants of treatment practice included residency environment,…

  14. Challenges to successful implementation of HIV and AIDS-related health policies in Cartagena, Colombia.

    PubMed

    Djellouli, Nehla; Quevedo-Gómez, María Cristina

    2015-05-01

    The Caribbean region presents the highest prevalence of HIV/AIDS worldwide after sub-Saharan Africa; leading to serious social, economic and health consequences at the local scale but also at the regional and global levels. In Colombia, a national plan to tackle the epidemic was formulated with little evidence that its implementation in the local context is effective. This study focused on Cartagena - one of Colombia's largest cities and an international touristic hub - that presents one of the highest HIV prevalences in the country, to investigate whether the national plan accounts for local specificities and what are the barriers to local implementation. Based on the Contextual Interaction Theory (CIT), this qualitative research relied upon 27 interviews and 13 life stories of local inhabitants and stakeholders, collected in a first fieldwork in 2006-2007. A follow-up data collection took place in 2013 with 10 participants: key policymakers and implementers, NGO representatives and local inhabitants. Barriers identified by the participants included: local population's understandings and beliefs on condom use; stigma and discrimination; lack of collaboration from the Church, the education sector and local politicians; corruption; high staff turnover; frequent changes in leadership; lack of economic and human resources; and barriers to health care access. The findings suggest that global influences also have an impact on the CIT framework (e.g. international organisations as a major financier in HIV prevention). The participants put forward several feasible solutions to implementation barriers. We discuss how several of the proposed solutions have been applied in other Latin American and Caribbean countries and yielded positive results. However, further research is needed to find possible ways of overcoming certain barriers identified by this study such as corruption, the lack of collaboration of the Church and barriers to health care access. PMID:25840048

  15. AIDS-related experiences of primary care physicians in rural California, 1995.

    PubMed Central

    Lewis, C E

    1996-01-01

    A telephone survey was conducted of primary care physicians in nonmetropolitan counties of California. In a random sample of those counties reporting fewer than 30 cases of the acquired immunodeficiency syndrome (AIDS) as of December 1994, all physicians in practice were called; in counties reporting from 31 to 150 cases of AIDS as of the same date, a 30% random sample was selected for interviewing. Completion rates were 82% in the smallest counties and 70% in the larger counties (overall 72%). Two thirds of physicians reported that they had seen a patient positive for the human immunodeficiency virus and were providing continuing care for the disease. In all, 60% of physicians had seen a patient with AIDS. In these counties, there were 653 primary care physicians and 873 patients living with AIDS. The proportion of physicians providing care to persons with AIDS was twice that reported in previous surveys done in Los Angeles, California. In the interval (1985-1994), there was a 20-fold increase in the number of AIDS cases in California. In the nonmetropolitan areas, the number of AIDS cases in late 1994 was 290 times that reported in 1985. PMID:8686298

  16. Predictors of Grief and Depressed Mood among Gay Men Following an Aids-Related Loss

    ERIC Educational Resources Information Center

    Wayment, Heidi A.; Kemeny, Margaret E.

    2004-01-01

    This prospective study examined the unique predictors of grief and depressed mood in a sample of gay men (34 HIV positive, 69 HIV negative) who lost a close friend to AIDS. Individuals low in self-esteem reported greater depressed mood but no differences in grief following the death. Individuals with personality factors that predispose toward…

  17. Human Exportin-1 is a Target for Combined Therapy of HIV and AIDS Related Lymphoma.

    PubMed

    Boons, Eline; Vanstreels, Els; Jacquemyn, Maarten; Nogueira, Tatiane C; Neggers, Jasper E; Vercruysse, Thomas; van den Oord, Joost; Tamir, Sharon; Shacham, Sharon; Landesman, Yosef; Snoeck, Robert; Pannecouque, Christophe; Andrei, Graciela; Daelemans, Dirk

    2015-09-01

    Infection with HIV ultimately leads to advanced immunodeficiency resulting in an increased incidence of cancer. For example primary effusion lymphoma (PEL) is an aggressive non-Hodgkin lymphoma with very poor prognosis that typically affects HIV infected individuals in advanced stages of immunodeficiency. Here we report on the dual anti-HIV and anti-PEL effect of targeting a single process common in both diseases. Inhibition of the exportin-1 (XPO1) mediated nuclear transport by clinical stage orally bioavailable small molecule inhibitors (SINE) prevented the nuclear export of the late intron-containing HIV RNA species and consequently potently suppressed viral replication. In contrast, in CRISPR-Cas9 genome edited cells expressing mutant C528S XPO1, viral replication was unaffected upon treatment, clearly demonstrating the anti-XPO1 mechanism of action. At the same time, SINE caused the nuclear accumulation of p53 tumor suppressor protein as well as inhibition of NF-κB activity in PEL cells resulting in cell cycle arrest and effective apoptosis induction. In vivo, oral administration arrested PEL tumor growth in engrafted mice. Our findings provide strong rationale for inhibiting XPO1 as an innovative strategy for the combined anti-retroviral and anti-neoplastic treatment of HIV and PEL and offer perspectives for the treatment of other AIDS-associated cancers and potentially other virus-related malignancies. PMID:26501108

  18. Human Exportin-1 is a Target for Combined Therapy of HIV and AIDS Related Lymphoma

    PubMed Central

    Boons, Eline; Vanstreels, Els; Jacquemyn, Maarten; Nogueira, Tatiane C.; Neggers, Jasper E.; Vercruysse, Thomas; van den Oord, Joost; Tamir, Sharon; Shacham, Sharon; Landesman, Yosef; Snoeck, Robert; Pannecouque, Christophe; Andrei, Graciela; Daelemans, Dirk

    2015-01-01

    Infection with HIV ultimately leads to advanced immunodeficiency resulting in an increased incidence of cancer. For example primary effusion lymphoma (PEL) is an aggressive non-Hodgkin lymphoma with very poor prognosis that typically affects HIV infected individuals in advanced stages of immunodeficiency. Here we report on the dual anti-HIV and anti-PEL effect of targeting a single process common in both diseases. Inhibition of the exportin-1 (XPO1) mediated nuclear transport by clinical stage orally bioavailable small molecule inhibitors (SINE) prevented the nuclear export of the late intron-containing HIV RNA species and consequently potently suppressed viral replication. In contrast, in CRISPR-Cas9 genome edited cells expressing mutant C528S XPO1, viral replication was unaffected upon treatment, clearly demonstrating the anti-XPO1 mechanism of action. At the same time, SINE caused the nuclear accumulation of p53 tumor suppressor protein as well as inhibition of NF-κB activity in PEL cells resulting in cell cycle arrest and effective apoptosis induction. In vivo, oral administration arrested PEL tumor growth in engrafted mice. Our findings provide strong rationale for inhibiting XPO1 as an innovative strategy for the combined anti-retroviral and anti-neoplastic treatment of HIV and PEL and offer perspectives for the treatment of other AIDS-associated cancers and potentially other virus-related malignancies. PMID:26501108

  19. Exploring the realities of HIV/AIDS-related discrimination in Manila, Philippines.

    PubMed

    Ortega, N L; Bicaldo, B F; Sobritchea, C; Tan, M L

    2005-07-01

    Operating according to UNAIDS' 'Protocol for the Identification of Discrimination against People Living with HIV', this study analysed health infrastructure in Manila, Philippines and determined that despite the existence of anti-discriminatory legislation, discrimination still occurred in practice. This was attributed to an absence of written regulations and inadequate training among health staff. Discrimination associated with HIV/AIDS has been found to be a hindrance to the development of successful preventive strategies, as it discourages people living with HIV/AIDS (PLWHA) and other people from contacting health and social services. This paper argues that if the Philippines is to maintain its low prevalence rate of HIV (and even reduce it), the discrimination that PLWHA incur must be addressed taking account of their human rights. PMID:16174626

  20. Evolution of college students' AIDS-related behavioral responses, attitudes, knowledge, and fear.

    PubMed

    Fisher, J D; Misovich, S J

    1990-01-01

    Data were collected (a) to document extant levels of AIDS-risk behavior, AIDS-preventive behavior, AIDS-knowledge, and attitudes toward prevention among college students, (b) to assess the evolution from 1986 to 1988 of college students' behavioral and attitudinal responses to the AIDS epidemic, and (c) to document changes over time in college students' knowledge about AIDS. Although students' current levels of AIDS-knowledge were found to be relatively high, and their attitudes toward prevention were in the neutral range, actual preventive behavior was low, and unsafe sexual practices were high. Concerning changes in these dimensions across time, data using comparable samples of undergraduates in 1986, 1987, and 1988 indicated that there were substantial increases in knowledge about AIDS, in the favorability of attitudes toward certain "safer-sex" behaviors (e.g., discussing "safer sex"), and in the utilization of relevant informational resources. Students' perceptions of others' vulnerability to AIDS (but not their own vulnerability), had also increased. However, at the same time, students reported a decrease in the safety of their sexual behaviors. Numbers of sexual partners, likelihood of being in an intimate (sexual) relationship, and unsafe sexual practices have all increased since 1986. Finally, evidence suggested that alcohol may play a significant role in students' AIDS-risk behavior. PMID:2288814

  1. Physicians Mutual Aid Group: A Response to AIDS-Related Burnout.

    ERIC Educational Resources Information Center

    Garside, Bruce

    1993-01-01

    Describes origins and functioning of physician's mutual aid group for physicians providing primary care to people with Acquired Immune Deficiency Syndrome (AIDS). Offers suggestions related to overcoming resistance physicians might have to participating in such a group and reviews modalities that were helpful in facilitating participants' ability…

  2. AIDS Related Stigma in Social Relations: A Qualitative Study in Turkey

    ERIC Educational Resources Information Center

    Kasapoglu, Aytul; Saillard, Elif Kus; Kaya, Nilay; Turan, Feryal

    2011-01-01

    The actual number of HIV/AIDS cases in Turkey is higher than the number of cases reported, and People Living with HIV (PLWHIV) may refrain from acknowledging their sickness or seeking help because of the stigma associated with HIV and fear of discrimination from their close friends, workmates, and even their families. In this paper we aim to…

  3. Internalized HIV/AIDS-related stigma in a sample of HIV-positive people in Bangladesh.

    PubMed

    Hasan, M Tanvir; Nath, Samir Ranjan; Khan, Nabilah S; Akram, Owasim; Gomes, Tony Michael; Rashid, Sabina F

    2012-03-01

    Internalized stigma among people living with HIV/AIDS (PLHA) is prevalent in Bangladesh. A better understanding of the effects of stigma on PLHA is required to reduce this and to minimize its harmful effects. This study employed a quantitative approach by conducting a survey with an aim to know the prevalence of internalized stigma and to identify the factors associated with internalized stigma among a sample of 238 PLHA (male=152 and female=86) in Bangladesh. The findings suggest that there is a significant difference between groups with the low- and the high-internalized HIV/AIDS stigma in terms of both age and gender. The prevalence of internalized stigma varied according to the poverty status of PLHA. An exploratory factor analysis (EFA) found 10 of 15 items loaded highly on the three factors labelled self-acceptance, self-exclusion, and social withdrawal. About 68% of the PLHA felt ashamed, and 54% felt guilty because of their HIV status. More than half (87.5% male and 19.8% female) of the PLHA blamed themselves for their HIV status while many of them (38.2% male and 8.1% female) felt that they should be punished. The male PLHA more frequently chose to withdraw themselves from family and social gatherings compared to the female PLHA. They also experienced a higher level of internalized stigma compared to the female PLHA. The results suggest that the prevalence of internalized stigma is high in Bangladesh, and much needs to be done by different organizations working for and with the PLHA to reduce internalized stigma among this vulnerable group. PMID:22524116

  4. Prediction of grief and HIV/AIDS-related burnout in volunteers.

    PubMed

    Nesbitt, W H; Ross, M W; Sunderland, R H; Shelp, E

    1996-04-01

    Burnout in volunteer workers in the HIV/AIDS area results in the loss of dedicated personnel, consequently straining the HIV/AIDS care delivery system. By assessing the predictors of burnout and grief this study describes the role of grief in HIV/AIDS volunteer burnout. Voluntary and anonymous questionnaires were sent to members of the Foundation for Interfaith Research and Ministry (FIRM), a multi-religious organization formed to provide volunteer work in HIV/AIDS care facilities around Houston, Texas. In 174 valid responses, grief was measured against work characteristics, burnout, rewards, stressors, and the general health questionnaire (GHQ). No significant relationship was found between grief and burnout; however, burnout in volunteers may be different from that in health care professionals for the following reasons: (1) volunteers choose to work in the HIV/AIDS area; (2) they have control over the time they spend volunteering; (3) volunteers are internally motivated to work in the HIV/AIDS area; and (4) if the volunteers do not enjoy the work, they can terminate their involvement with minimal cost. The best univariate predictors of grief are time spent as a volunteer and volunteer hours per week, where those who spend the most hours volunteering experience less grief The Reward/Stress measures most significantly associated with grief include empathy/self-knowing reward, emotional support reward, and emotional overload stress. The strongest predictors of grief in the regression analysis, which account for 21% of the variance, were time as a volunteer, emotional support, emotional overload, GHQ-somatic symptoms, and GHQ social dysfunction. The data suggest that in order to reduce grief special attention should be paid te allowing volunteers freely to express problems with emotional overload and workload adjustments, and providing clear emotional support as a reward. PMID:8861413

  5. [Acetaminophen-induced hypothermia, an AIDS related side-effect? About 4 cases].

    PubMed

    Denes, Eric; Amaniou, Monique; Rogez, Jean-Philippe; Weinbreck, Pierre; Merle, Louis

    2002-10-01

    Hypothermia is an uncommon side effect of acetaminophen. We report 4 cases of HIV-infected patients who developed hypothermia after intravenous injection of propacetamol (the parenteral formulation of acetaminophen). The mechanism of this hypothermia is unknown. AIDS-induced changes in the metabolism of acetaminophen, could be an explanation. AIDS-associated opportunistic diseases may account for part of the mechanism. These hypothermias occur within 6 hours after the injection, are well tolerated and regress spontaneously. PMID:12486392

  6. Reacting to AIDS-Related Suicide: Does Time since Diagnosis Matter?

    ERIC Educational Resources Information Center

    Range, Lillian M.; Alliston, Jerry R.

    1995-01-01

    Undergraduates (n=296) read a fictional vignette concerning a person diagnosed with either terminal cancer or AIDS, and for varying lengths of time. Student reactions indicated that a person with AIDS is associated with greater stigma than a person with another fatal disease, regardless of how long ago the diagnosis was made. (JPS)

  7. Responding to AIDS-Related Bereavement in the South African Context

    ERIC Educational Resources Information Center

    Demmer, Craig

    2007-01-01

    AIDS continues to be a death sentence for many individuals living in South Africa where it remains the leading cause of death. Little is currently known about what it is like to experience the loss of a loved one to AIDS from the South African perspective and how to assist individuals who are living in a context vastly different from similarly…

  8. HIV/AIDS-related stigma and information behaviour: an ethnographic study in the UK.

    PubMed

    Namuleme, Robinah Kalemeera

    2015-03-01

    This feature explores the information behaviour of people infected with or affected by HIV/AIDS. It investigates specifically the difficult issue of stigma and how this shapes the ways in which people interact with vital information. The study adopted an ethnographic whereby the researcher worked as a part-time volunteer at an HIV support centre in the North of England for over a year. This is the first time that such an approach has been reported in this feature and is interesting from this perspective alone. The very rich data which was gathered as a result of the approach is also instructive. The study formed part of a PhD thesis, which Robinah Kalemeera Namuleme completed at the University of Sheffield in March 2013. PMID:25684027

  9. Epidemic of AIDS related virus (HTLV-III/LAV) infection among intravenous drug abusers.

    PubMed

    Robertson, J R; Bucknall, A B; Welsby, P D; Roberts, J J; Inglis, J M; Peutherer, J F; Brettle, R P

    1986-02-22

    Stored blood samples from 164 intravenous drug abusers who attended a Scottish general practice were tested for HTLV-III/LAV (human T cell lymphotropic virus type III/lymphadenopathy associated virus) infection. Of those tested, 83 (51%) were seropositive, which is well above the prevalence reported elsewhere in Britain and Europe and approaches that observed in New York City. The timing of taking samples of negative sera and continued drug use suggest that as many as 85% of this population might now be infected. The infection became epidemic in late 1983 and early 1984, thereafter becoming endemic. The practice of sharing needles and syringes correlated with seropositivity, which, combined with the almost exclusive intravenous use of heroin and other behavioural patterns, may explain the high prevalence of HTLV-III/LAV infection in the area. Rapid and aggressive intervention is needed to control the spread of infection. PMID:3081158

  10. Immunophototherapy for the treatment of AIDS and AIDS-related infections

    NASA Astrophysics Data System (ADS)

    Schlager, Kenneth J.

    1992-06-01

    Immunophototherapy (IPT) is an experimental method of medical treatment that seeks to provide for the selective destruction of diseased cells and microbes such as human immunodeficiency virus (HIV)-T4 cells and the rapid elimination of their toxic by-products from the human body. Photosensitive monoclonal or polyclonal antibody fragments, which are specific to the diseased cell or microbe, will be used to treat acquired immunodeficiency syndrome (AIDS) and related infections. These antibody fragments are tagged with photosensitive compounds and metal colloids and then intravenously injected into the patient. The tagged antibodies quickly and selectively bind to the diseased cells or microbes in the blood stream and affected organs. These cells or microbes are then selectively destroyed by irradiation of these complexes with light of the proper wavelength. This light activates the photosensitive material which then creates singlet oxygen that destroys the microbe or cell. Toxic products of lysis are quickly discharged from the body by activation of the reticuloendothelial system. IPT has been demonstrated by Biotronics to be very effective in the in vitro selective destruction of specified cell types. In a proposed AIDS-treatment research program, IPT will be first demonstrated in vitro for a set of infected blood samples using commercially-available antibodies labeled with appropriate photosensitizers. Efficacy will be determined by a p24 antigen immunodiagnostic test that will indicate the % inhibition in comparison to controls and samples treated with the drug AZT. Subcontracted animal efficacy studies will use a SCID-hu mouse model and PCR/DNA-RNA for endpoint analysis. Toxicity studies of animal (rat) models will be based on post-treatment investigations of lymph nodes, spleen, liver and other organs.

  11. Large Binocular Telescope Project

    NASA Astrophysics Data System (ADS)

    Hill, John M.

    1997-03-01

    The large binocular telescope (LBT) project have evolved from concepts first proposed in 1985. The present partners involved in the design and construction of this 2 by 8.4 meter binocular telescope are the University of Arizona, Italy represented by the Osservatorio Astrofisico di Arcetri and the Research Corporation based in Tucson, Arizona. These three partners have committed sufficient funds to build the enclosure and the telescope populated with a single 8.4 meter optical train -- approximately 40 million dollars (1989). Based on this commitment, design and construction activities are now moving forward. Additional partners are being sought. The next mirror to be cast at the Steward Observatory Mirror Lab in the fall of 1996 will be the first borosilicate honeycomb primary for LBT. The baseline optical configuration of LBT includes wide field Cassegrain secondaries with optical foci above the primaries to provide a corrected one degree field at F/4. The infrared F/15 secondaries are a Gregorian design to allow maximum flexibility for adaptive optics. The F/15 secondaries are undersized to provide a low thermal background focal plane which is unvignetted over a 4 arcminute diameter field-of-view. The interferometric focus combining the light from the two 8.4 meter primaries will reimage two folded Gregorian focal planes to a central location. The telescope elevation structure accommodates swing arms which allow rapid interchange of the various secondary and tertiary mirrors. Maximum stiffness and minimal thermal disturbance continue to be important drivers for the detailed design of the telescope. The telescope structure accommodates installation of a vacuum bell jar for aluminizing the primary mirrors in-situ on the telescope. The detailed design of the telescope structure will be completed in 1996 by ADS Italia (Lecco) and European Industrial Engineering (Mestre). The final enclosure design is now in progress at M3 Engineering (Tucson), EIE and ADS Italia

  12. Applied large eddy simulation.

    PubMed

    Tucker, Paul G; Lardeau, Sylvain

    2009-07-28

    Large eddy simulation (LES) is now seen more and more as a viable alternative to current industrial practice, usually based on problem-specific Reynolds-averaged Navier-Stokes (RANS) methods. Access to detailed flow physics is attractive to industry, especially in an environment in which computer modelling is bound to play an ever increasing role. However, the improvement in accuracy and flow detail has substantial cost. This has so far prevented wider industrial use of LES. The purpose of the applied LES discussion meeting was to address questions regarding what is achievable and what is not, given the current technology and knowledge, for an industrial practitioner who is interested in using LES. The use of LES was explored in an application-centred context between diverse fields. The general flow-governing equation form was explored along with various LES models. The errors occurring in LES were analysed. Also, the hybridization of RANS and LES was considered. The importance of modelling relative to boundary conditions, problem definition and other more mundane aspects were examined. It was to an extent concluded that for LES to make most rapid industrial impact, pragmatic hybrid use of LES, implicit LES and RANS elements will probably be needed. Added to this further, highly industrial sector model parametrizations will be required with clear thought on the key target design parameter(s). The combination of good numerical modelling expertise, a sound understanding of turbulence, along with artistry, pragmatism and the use of recent developments in computer science should dramatically add impetus to the industrial uptake of LES. In the light of the numerous technical challenges that remain it appears that for some time to come LES will have echoes of the high levels of technical knowledge required for safe use of RANS but with much greater fidelity. PMID:19531503

  13. Combination Chemotherapy and Rituximab in Treating Young Patients With Recurrent or Refractory Non-Hodgkin's Lymphoma or Acute Lymphoblastic Leukemia

    ClinicalTrials.gov

    2013-10-07

    B-cell Childhood Acute Lymphoblastic Leukemia; Childhood Burkitt Lymphoma; Childhood Diffuse Large Cell Lymphoma; Childhood Immunoblastic Large Cell Lymphoma; L3 Childhood Acute Lymphoblastic Leukemia; Recurrent Childhood Acute Lymphoblastic Leukemia; Recurrent Childhood Large Cell Lymphoma; Recurrent Childhood Lymphoblastic Lymphoma; Recurrent Childhood Small Noncleaved Cell Lymphoma

  14. Large planer for finishing smooth, flat surfaces of large pieces ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Large planer for finishing smooth, flat surfaces of large pieces of metal; in operating condition and used for public demonstrations. - Thomas A. Edison Laboratories, Building No. 5, Main Street & Lakeside Avenue, West Orange, Essex County, NJ

  15. Large for gestational age (LGA)

    MedlinePlus

    ... medlineplus.gov/ency/article/002248.htm Large for gestational age (LGA) To use the sharing features on this page, please enable JavaScript. Large for gestational age means that a fetus or infant is larger ...

  16. Large-D gravity and low-D strings.

    PubMed

    Emparan, Roberto; Grumiller, Daniel; Tanabe, Kentaro

    2013-06-21

    We show that in the limit of a large number of dimensions a wide class of nonextremal neutral black holes has a universal near-horizon limit. The limiting geometry is the two-dimensional black hole of string theory with a two-dimensional target space. Its conformal symmetry explains the properties of massless scalars found recently in the large-D limit. For black branes with string charges, the near-horizon geometry is that of the three-dimensional black strings of Horne and Horowitz. The analogies between the α' expansion in string theory and the large-D expansion in gravity suggest a possible effective string description of the large-D limit of black holes. We comment on applications to several subjects, in particular to the problem of critical collapse. PMID:23829726

  17. Health impacts of large dams

    SciTech Connect

    Lerer, L.B.; Scudder, T.

    1999-03-01

    Large dams have been criticized because of their negative environmental and social impacts. Public health interest largely has focused on vector-borne diseases, such as schistosomiasis, associated with reservoirs and irrigation projects. Large dams also influence health through changes in water and food security, increases in communicable diseases, and the social disruption caused by construction and involuntary resettlement. Communities living in close proximity to large dams often do not benefit from water transfer and electricity generation revenues. A comprehensive health component is required in environmental and social impact assessments for large dam projects.

  18. Bryostatin and Vincristine in B-Cell Malignancies

    ClinicalTrials.gov

    2013-01-10

    Recurrent Adult Burkitt Lymphoma; Recurrent Adult Diffuse Large Cell Lymphoma; Recurrent Adult Diffuse Mixed Cell Lymphoma; Recurrent Adult Immunoblastic Large Cell Lymphoma; Recurrent Adult Lymphoblastic Lymphoma; Recurrent Grade 3 Follicular Lymphoma; Recurrent Mantle Cell Lymphoma; Refractory Chronic Lymphocytic Leukemia; Refractory Multiple Myeloma; Stage III Multiple Myeloma

  19. CD19 CAR T Cells for B Cell Malignancies After Allogeneic Transplant

    ClinicalTrials.gov

    2015-08-04

    Philadelphia Chromosome Negative Adult Precursor Acute Lymphoblastic Leukemia; Philadelphia Chromosome Positive Adult Precursor Acute Lymphoblastic Leukemia; Recurrent Adult Acute Lymphoblastic Leukemia; Recurrent Adult Diffuse Large Cell Lymphoma; Recurrent Adult Immunoblastic Large Cell Lymphoma; Recurrent Mantle Cell Lymphoma; Refractory Chronic Lymphocytic Leukemia

  20. Interleukin-2 or Observation Following Radiation Therapy, Combination Chemotherapy, and Peripheral Stem Cell Transplantation in Treating Patients With Recurrent Non-Hodgkin's Lymphoma

    ClinicalTrials.gov

    2013-02-27

    Recurrent Adult Burkitt Lymphoma; Recurrent Adult Diffuse Large Cell Lymphoma; Recurrent Adult Diffuse Mixed Cell Lymphoma; Recurrent Adult Diffuse Small Cleaved Cell Lymphoma; Recurrent Adult Immunoblastic Large Cell Lymphoma; Recurrent Grade 1 Follicular Lymphoma; Recurrent Grade 2 Follicular Lymphoma; Recurrent Grade 3 Follicular Lymphoma

  1. Analytic bootstrap at large spin

    NASA Astrophysics Data System (ADS)

    Kaviraj, Apratim; Sen, Kallol; Sinha, Aninda

    2015-11-01

    We use analytic conformal bootstrap methods to determine the anomalous dimensions and OPE coefficients for large spin operators in general conformal field theories in four dimensions containing a scalar operator of conformal dimension Δ ϕ . It is known that such theories will contain an infinite sequence of large spin operators with twists approaching 2Δ ϕ + 2 n for each integer n. By considering the case where such operators are separated by a twist gap from other operators at large spin, we analytically determine the n, Δ ϕ dependence of the anomalous dimensions. We find that for all n, the anomalous dimensions are negative for Δ ϕ satisfying the unitarity bound. We further compute the first subleading correction at large spin and show that it becomes universal for large twist. In the limit when n is large, we find exact agreement with the AdS/CFT prediction corresponding to the Eikonal limit of a 2-2 scattering with dominant graviton exchange.

  2. Querying Large Biological Network Datasets

    ERIC Educational Resources Information Center

    Gulsoy, Gunhan

    2013-01-01

    New experimental methods has resulted in increasing amount of genetic interaction data to be generated every day. Biological networks are used to store genetic interaction data gathered. Increasing amount of data available requires fast large scale analysis methods. Therefore, we address the problem of querying large biological network datasets.…

  3. Team Learning in Large Classes.

    ERIC Educational Resources Information Center

    Roueche, Suanne D., Ed.

    1984-01-01

    Information and suggestions are provided on the use of team learning in large college classes. Introductory material discusses the negative cycle of student-teacher interaction that may be provoked by large classes, and the use of permanent, heterogeneous, six- or seven-member student learning groups as the central focus of class activity as a…

  4. Robust large dimension terahertz cloaking.

    PubMed

    Liang, Dachuan; Gu, Jianqiang; Han, Jiaguang; Yang, Yuanmu; Zhang, Shuang; Zhang, Weili

    2012-02-14

    A large scale homogenous invisibility cloak functioning at terahertz frequencies is reported. The terahertz invisibility device features a large concealed volume, low loss, and broad bandwidth. In particular, it is capable of hiding objects with a dimension nearly an order of magnitude larger than that of its lithographic counterpart, but without involving complex and time-consuming cleanroom processing. PMID:22253094

  5. Sharpen Your Skills: Large Type.

    ERIC Educational Resources Information Center

    Knisely, Phillis; Wickham, Marian

    1984-01-01

    Three short articles about large type transcribing are provided for braille transcribers and teachers of the visually handicapped. The first article lists general suggestions for simple typewriter maintenance. The second article reviews the guidelines for typing fractions in large type for mathematics exercises. The third article describes a…

  6. Measuring happiness in large population

    NASA Astrophysics Data System (ADS)

    Wenas, Annabelle; Sjahputri, Smita; Takwin, Bagus; Primaldhi, Alfindra; Muhamad, Roby

    2016-01-01

    The ability to know emotional states for large number of people is important, for example, to ensure the effectiveness of public policies. In this study, we propose a measure of happiness that can be used in large scale population that is based on the analysis of Indonesian language lexicons. Here, we incorporate human assessment of Indonesian words, then quantify happiness on large-scale of texts gathered from twitter conversations. We used two psychological constructs to measure happiness: valence and arousal. We found that Indonesian words have tendency towards positive emotions. We also identified several happiness patterns during days of the week, hours of the day, and selected conversation topics.

  7. Large engines and vehicles, 1958

    NASA Technical Reports Server (NTRS)

    1978-01-01

    During the mid-1950s, the Air Force sponsored work on the feasibility of building large, single-chamber engines, presumably for boost-glide aircraft or spacecraft. In 1956, the Army missile development group began studies of large launch vehicles. The possibilities opened up by Sputnik accelerated this work and gave the Army an opportunity to bid for the leading role in launch vehicles. The Air Force had the responsibility for the largest ballistic missiles and hence a ready-made base for extending their capability for spaceflight. During 1958, actions taken to establish a civilian space agency, and the launch vehicle needs seen by its planners, added a third contender to the space vehicle competition. These activities during 1958 are examined as to how they resulted in the initiation of a large rocket engine and the first large launch vehicle.

  8. LSD: Large Survey Database framework

    NASA Astrophysics Data System (ADS)

    Juric, Mario

    2012-09-01

    The Large Survey Database (LSD) is a Python framework and DBMS for distributed storage, cross-matching and querying of large survey catalogs (>10^9 rows, >1 TB). The primary driver behind its development is the analysis of Pan-STARRS PS1 data. It is specifically optimized for fast queries and parallel sweeps of positionally and temporally indexed datasets. It transparently scales to more than >10^2 nodes, and can be made to function in "shared nothing" architectures.

  9. Does Yellowstone need large fires

    SciTech Connect

    Romme, W.H. ); Turner, M.G.; Gardner, R.H.; Hargrove, W.W. )

    1994-06-01

    This paper synthesizes several studies initiated after the 1988 Yellowstone fires, to address the question whether the ecological effects of large fires differ qualitatively as well as quantitatively from small fires. Large burn patches had greater dominance and contagion of burn severity classes, and a higher proportion of crown fire. Burned aspen stands resprouted vigorously over an extensive area, but heavy ungulate browsing prevented establishment of new tree-sized stems. A burst of sexual reproduction occurred in forest herbs that usually reproduce vegetatively, and new aspen clones became established from seed - a rare event in this region. We conclude that the effects of large fires are qualitatively different, but less dramatically so than expected.

  10. Inflating with large effective fields

    SciTech Connect

    Burgess, C.P.; Cicoli, M.; Quevedo, F.; Williams, M. E-mail: mcicoli@ictp.it E-mail: mwilliams@perimeterinsititute.ca

    2014-11-01

    We re-examine large scalar fields within effective field theory, in particular focussing on the issues raised by their use in inflationary models (as suggested by BICEP2 to obtain primordial tensor modes). We argue that when the large-field and low-energy regimes coincide the scalar dynamics is most effectively described in terms of an asymptotic large-field expansion whose form can be dictated by approximate symmetries, which also help control the size of quantum corrections. We discuss several possible symmetries that can achieve this, including pseudo-Goldstone inflatons characterized by a coset G/H (based on abelian and non-abelian, compact and non-compact symmetries), as well as symmetries that are intrinsically higher dimensional. Besides the usual trigonometric potentials of Natural Inflation we also find in this way simple large-field power laws (like V ∝ φ{sup 2}) and exponential potentials, V(φ) = ∑{sub k}V{sub x}e{sup −kφ/M}. Both of these can describe the data well and give slow-roll inflation for large fields without the need for a precise balancing of terms in the potential. The exponential potentials achieve large r through the limit |η| || ε and so predict r ≅ (8/3)(1-n{sub s}); consequently n{sub s} ≅ 0.96 gives r ≅ 0.11 but not much larger (and so could be ruled out as measurements on r and n{sub s} improve). We examine the naturalness issues for these models and give simple examples where symmetries protect these forms, using both pseudo-Goldstone inflatons (with non-abelian non-compact shift symmetries following familiar techniques from chiral perturbation theory) and extra-dimensional models.

  11. The MAGNEX large acceptance spectrometer

    SciTech Connect

    Cavallaro, M.; Cappuzzello, F.; Cunsolo, A.; Carbone, D.; Foti, A.

    2010-03-01

    The main features of the MAGNEX large acceptance magnetic spectrometer are described. It has a quadrupole + dipole layout and a hybrid detector located at the focal plane. The aberrations due to the large angular (50 msr) and momentum (+- 13%) acceptance are reduced by an accurate hardware design and then compensated by an innovative software ray-reconstruction technique. The obtained resolution in energy, angle and mass are presented in the paper. MAGNEX has been used up to now for different experiments in nuclear physics and astrophysics confirming to be a multipurpose device.

  12. Detecting communities in large networks

    NASA Astrophysics Data System (ADS)

    Capocci, A.; Servedio, V. D. P.; Caldarelli, G.; Colaiori, F.

    2005-07-01

    We develop an algorithm to detect community structure in complex networks. The algorithm is based on spectral methods and takes into account weights and link orientation. Since the method detects efficiently clustered nodes in large networks even when these are not sharply partitioned, it turns to be specially suitable for the analysis of social and information networks. We test the algorithm on a large-scale data-set from a psychological experiment of word association. In this case, it proves to be successful both in clustering words, and in uncovering mental association patterns.

  13. Fermi's Large Area Telescope (LAT)

    NASA Video Gallery

    Fermi’s Large Area Telescope (LAT) is the spacecraft’s main scientificinstrument. This animation shows a gamma ray (purple) entering the LAT,where it is converted into an electron (red) and a...

  14. The very large hadron collider

    SciTech Connect

    1998-09-01

    This paper reviews the purposes to be served by a very large hadron collider and the organization and coordination of efforts to bring it about. There is some discussion of magnet requirements and R&D and the suitability of the Fermilab site.

  15. Ideas for Managing Large Classes.

    ERIC Educational Resources Information Center

    Kabel, Robert L.

    1983-01-01

    Describes management strategies used in a large kinetics/industrial chemistry course. Strategies are designed to make instruction in such classes more efficient and effective. Areas addressed include homework assignment, quizzes, final examination, grading and feedback, and rewards for conducting the class in the manner described. (JN)

  16. CERN's Large Hadron Collider project

    NASA Astrophysics Data System (ADS)

    Fearnley, Tom A.

    1997-03-01

    The paper gives a brief overview of CERN's Large Hadron Collider (LHC) project. After an outline of the physics motivation, we describe the LHC machine, interaction rates, experimental challenges, and some important physics channels to be studied. Finally we discuss the four experiments planned at the LHC: ATLAS, CMS, ALICE and LHC-B.

  17. Large area CMOS image sensors

    NASA Astrophysics Data System (ADS)

    Turchetta, R.; Guerrini, N.; Sedgwick, I.

    2011-01-01

    CMOS image sensors, also known as CMOS Active Pixel Sensors (APS) or Monolithic Active Pixel Sensors (MAPS), are today the dominant imaging devices. They are omnipresent in our daily life, as image sensors in cellular phones, web cams, digital cameras, ... In these applications, the pixels can be very small, in the micron range, and the sensors themselves tend to be limited in size. However, many scientific applications, like particle or X-ray detection, require large format, often with large pixels, as well as other specific performance, like low noise, radiation hardness or very fast readout. The sensors are also required to be sensitive to a broad spectrum of radiation: photons from the silicon cut-off in the IR down to UV and X- and gamma-rays through the visible spectrum as well as charged particles. This requirement calls for modifications to the substrate to be introduced to provide optimized sensitivity. This paper will review existing CMOS image sensors, whose size can be as large as a single CMOS wafer, and analyse the technical requirements and specific challenges of large format CMOS image sensors.

  18. Large deviations and portfolio optimization

    NASA Astrophysics Data System (ADS)

    Sornette, Didier

    Risk control and optimal diversification constitute a major focus in the finance and insurance industries as well as, more or less consciously, in our everyday life. We present a discussion of the characterization of risks and of the optimization of portfolios that starts from a simple illustrative model and ends by a general functional integral formulation. A major item is that risk, usually thought of as one-dimensional in the conventional mean-variance approach, has to be addressed by the full distribution of losses. Furthermore, the time-horizon of the investment is shown to play a major role. We show the importance of accounting for large fluctuations and use the theory of Cramér for large deviations in this context. We first treat a simple model with a single risky asset that exemplifies the distinction between the average return and the typical return and the role of large deviations in multiplicative processes, and the different optimal strategies for the investors depending on their size. We then analyze the case of assets whose price variations are distributed according to exponential laws, a situation that is found to describe daily price variations reasonably well. Several portfolio optimization strategies are presented that aim at controlling large risks. We end by extending the standard mean-variance portfolio optimization theory, first within the quasi-Gaussian approximation and then using a general formulation for non-Gaussian correlated assets in terms of the formalism of functional integrals developed in the field theory of critical phenomena.

  19. Large gap magnetic suspension system

    NASA Technical Reports Server (NTRS)

    Abdelsalam, Moustafa K.; Eyssa, Y. M.

    1991-01-01

    The design of a large gap magnetic suspension system is discussed. Some of the topics covered include: the system configuration, permanent magnet material, levitation magnet system, superconducting magnets, resistive magnets, superconducting levitation coils, resistive levitation coils, levitation magnet system, and the nitrogen cooled magnet system.

  20. Mass spectrometry of large complexes.

    PubMed

    Bich, Claudia; Zenobi, Renato

    2009-10-01

    Mass spectrometry is becoming a more and more powerful tool for investigating protein complexes. Recent developments, based on different ionization techniques, electrospray, desorption/ionization and others are contributing to the usefulness of MS to describe the organization and structure of large non-covalent assemblies. PMID:19782560

  1. Unusually large submandibular gland stone.

    PubMed

    Al-Hussona, Aws Adel

    2015-01-01

    Submandibular gland calculi is the most common disease of the gland. In this article, we report a case with unusually large stone located at the hilum of the gland causing necrosis of the overlying duct and the oral mucosa (floor of mouth). PMID:25934409

  2. Energy conservation in large buildings

    NASA Astrophysics Data System (ADS)

    Rosenfeld, A.; Hafemeister, D.

    1985-11-01

    As energy prices rise, newly energy aware designers use better tools and technology to create energy efficient buildings. Thus the U.S. office stock (average age 20 years) uses 250 kBTU/ft2 of resource energy, but the guzzler of 1972 uses 500 (up×2), and the 1986 ASHRAE standards call for 100-125 (less than 25% of their 1972 ancestors). Surprisingly, the first real cost of these efficient buildings has not risen since 1972. Scaling laws are used to calculate heat gains and losses of buildings to obtain the ΔT(free) which can be as large as 15-30 °C (30-60 °F) for large buildings. The net thermal demand and thermal time constants are determined for the Swedish Thermodeck buildings which need essentially no heat in the winter and no chillers in summer. The BECA and other data bases for large buildings are discussed. Off-peak cooling for large buildings is analyzed in terms of saving peak-electrical power. By downsizing chillers and using cheaper, off-peak power, cost-effective thermal storage in new commercial buildings can reduce U.S. peak power demands by 10-20 GW in 15 years. A further potential of about 40 GW is available from adopting partial thermal storage and more efficient air conditioners in existing buildings.

  3. Galaxy clustering on large scales.

    PubMed

    Efstathiou, G

    1993-06-01

    I describe some recent observations of large-scale structure in the galaxy distribution. The best constraints come from two-dimensional galaxy surveys and studies of angular correlation functions. Results from galaxy redshift surveys are much less precise but are consistent with the angular correlations, provided the distortions in mapping between real-space and redshift-space are relatively weak. The galaxy two-point correlation function, rich-cluster two-point correlation function, and galaxy-cluster cross-correlation function are all well described on large scales ( greater, similar 20h-1 Mpc, where the Hubble constant, H0 = 100h km.s-1.Mpc; 1 pc = 3.09 x 10(16) m) by the power spectrum of an initially scale-invariant, adiabatic, cold-dark-matter Universe with Gamma = Omegah approximately 0.2. I discuss how this fits in with the Cosmic Background Explorer (COBE) satellite detection of large-scale anisotropies in the microwave background radiation and other measures of large-scale structure in the Universe. PMID:11607400

  4. Very Large Scale Integration (VLSI).

    ERIC Educational Resources Information Center

    Yeaman, Andrew R. J.

    Very Large Scale Integration (VLSI), the state-of-the-art production techniques for computer chips, promises such powerful, inexpensive computing that, in the future, people will be able to communicate with computer devices in natural language or even speech. However, before full-scale VLSI implementation can occur, certain salient factors must be…

  5. Large-scale polarimetry of large optical galaxies

    NASA Astrophysics Data System (ADS)

    Sholomitskii, G. B.; Maslov, I. A.; Vitrichenko, E. A.

    1999-11-01

    We present preliminary results of wide-field visual CCD polarimetry for large optical galaxies through a concentric multisector radial-tangential polaroid analyzer mounted at the intermediate focus of a Zeiss-1000 telescope. The mean degree of tangential polarization in a 13-arcmin field, which was determined by processing images with imprinted ``orthogonal'' sectors, ranges from several percent (M 82) and 0.51% (the spirals M 51, M 81) to lower values for elliptical galaxies (M 49, M 87). It is emphasized that the parameters of large-scale polarization can be properly determined by using physical models for galaxies; inclination and azimuthal dependences of the degree of polarization are given for spirals.

  6. The physics of large eruptions

    NASA Astrophysics Data System (ADS)

    Gudmundsson, Agust

    2015-04-01

    Based on eruptive volumes, eruptions can be classified as follows: small if the volumes are from less than 0.001 km3 to 0.1 km3, moderate if the volumes are from 0.1 to 10 km3, and large if the volumes are from 10 km3 to 1000 km3 or larger. The largest known explosive and effusive eruptions have eruptive volumes of 4000-5000 km3. The physics of small to moderate eruptions is reasonably well understood. For a typical mafic magma chamber in a crust that behaves as elastic, about 0.1% of the magma leaves the chamber (erupted and injected as a dyke) during rupture and eruption. Similarly, for a typical felsic magma chamber, the eruptive/injected volume during rupture and eruption is about 4%. To provide small to moderate eruptions, chamber volumes of the order of several tens to several hundred cubic kilometres would be needed. Shallow crustal chambers of these sizes are common, and deep-crustal and upper-mantle reservoirs of thousands of cubic kilometres exist. Thus, elastic and poro-elastic chambers of typical volumes can account for small to moderate eruptive volumes. When the eruptions become large, with volumes of tens or hundreds of cubic kilometres or more, an ordinary poro-elastic mechanism can no longer explain the eruptive volumes. The required sizes of the magma chambers and reservoirs to explain such volumes are simply too large to be plausible. Here I propose that the mechanics of large eruptions is fundamentally different from that of small to moderate eruptions. More specifically, I suggest that all large eruptions derive their magmas from chambers and reservoirs whose total cavity-volumes are mechanically reduced very much during the eruption. There are two mechanisms by which chamber/reservoir cavity-volumes can be reduced rapidly so as to squeeze out much of, or all, their magmas. One is piston-like caldera collapse. The other is graben subsidence. During large slip on the ring-faults/graben-faults the associated chamber/reservoir shrinks in volume

  7. Rituximab, Rasburicase, and Combination Chemotherapy in Treating Young Patients With Newly Diagnosed Advanced B-Cell Leukemia or Lymphoma

    ClinicalTrials.gov

    2014-09-10

    Childhood Burkitt Lymphoma; Childhood Diffuse Large Cell Lymphoma; Childhood Immunoblastic Large Cell Lymphoma; Stage I Childhood Large Cell Lymphoma; Stage I Childhood Small Noncleaved Cell Lymphoma; Stage II Childhood Large Cell Lymphoma; Stage II Childhood Small Noncleaved Cell Lymphoma; Stage III Childhood Large Cell Lymphoma; Stage III Childhood Small Noncleaved Cell Lymphoma; Stage IV Childhood Large Cell Lymphoma; Stage IV Childhood Small Noncleaved Cell Lymphoma; Untreated Childhood Acute Lymphoblastic Leukemia

  8. Large space structure damping design

    NASA Technical Reports Server (NTRS)

    Pilkey, W. D.; Haviland, J. K.

    1983-01-01

    Several FORTRAN subroutines and programs were developed which compute complex eigenvalues of a damped system using different approaches, and which rescale mode shapes to unit generalized mass and make rigid bodies orthogonal to each other. An analytical proof of a Minimum Constrained Frequency Criterion (MCFC) for a single damper is presented. A method to minimize the effect of control spill-over for large space structures is proposed. The characteristic equation of an undamped system with a generalized control law is derived using reanalysis theory. This equation can be implemented in computer programs for efficient eigenvalue analysis or control quasi synthesis. Methods to control vibrations in large space structure are reviewed and analyzed. The resulting prototype, using electromagnetic actuator, is described.

  9. Chunking of Large Multidimensional Arrays

    SciTech Connect

    Rotem, Doron; Otoo, Ekow J.; Seshadri, Sridhar

    2007-02-28

    Data intensive scientific computations as well on-lineanalytical processing applications as are done on very large datasetsthat are modeled as k-dimensional arrays. The storage organization ofsuch arrays on disks is done by partitioning the large global array intofixed size hyper-rectangular sub-arrays called chunks or tiles that formthe units of data transfer between disk and memory. Typical queriesinvolve the retrieval of sub-arrays in a manner that accesses all chunksthat overlap the query results. An important metric of the storageefficiency is the expected number of chunks retrieved over all suchqueries. The question that immediately arises is "what shapes of arraychunks give the minimum expected number of chunks over a query workload?"In this paper we develop two probabilistic mathematical models of theproblem and provide exact solutions using steepest descent and geometricprogramming methods. Experimental results, using synthetic workloads onreal life data sets, show that our chunking is much more efficient thanthe existing approximate solutions.

  10. Progress on large area GEMs

    NASA Astrophysics Data System (ADS)

    Villa, Marco; Duarte Pinto, Serge; Alfonsi, Matteo; Brock, Ian; Croci, Gabriele; David, Eric; de Oliveira, Rui; Ropelewski, Leszek; Taureg, Hans; van Stenis, Miranda

    2011-02-01

    The Gas Electron Multiplier (GEM) manufacturing technique has recently evolved to allow the production of large area GEMs. A novel approach based on single mask photolithography eliminates the mask alignment issue, which limits the dimensions in the traditional double mask process. Moreover, a splicing technique overcomes the limited width of the raw material. Stretching and handling issues in large area GEMs have also been addressed. Using the new improvements it was possible to build a prototype triple-GEM detector of ˜2000 cm2 active area, aimed at an application for the TOTEM T1 upgrade. Further refinements of the single mask technique allow great control over the shape of the GEM holes and the size of the rims, which can be tuned as needed. In this framework, simulation studies can help to understand the GEM behavior depending on the hole shape.

  11. Large aperture Fresnel telescopes/011

    SciTech Connect

    Hyde, R.A., LLNL

    1998-07-16

    At Livermore we`ve spent the last two years examining an alternative approach towards very large aperture (VLA) telescopes, one based upon transmissive Fresnel lenses rather than on mirrors. Fresnel lenses are attractive for VLA telescopes because they are launchable (lightweight, packagable, and deployable) and because they virtually eliminate the traditional, very tight, surface shape requirements faced by reflecting telescopes. Their (potentially severe) optical drawback, a very narrow spectral bandwidth, can be eliminated by use of a second (much smaller) chromatically-correcting Fresnel element. This enables Fresnel VLA telescopes to provide either single band ({Delta}{lambda}/{lambda} {approximately} 0.1), multiple band, or continuous spectral coverage. Building and fielding such large Fresnel lenses will present a significant challenge, but one which appears, with effort, to be solvable.

  12. Large aperture scanning airborne lidar

    NASA Technical Reports Server (NTRS)

    Smith, J.; Bindschadler, R.; Boers, R.; Bufton, J. L.; Clem, D.; Garvin, J.; Melfi, S. H.

    1988-01-01

    A large aperture scanning airborne lidar facility is being developed to provide important new capabilities for airborne lidar sensor systems. The proposed scanning mechanism allows for a large aperture telescope (25 in. diameter) in front of an elliptical flat (25 x 36 in.) turning mirror positioned at a 45 degree angle with respect to the telescope optical axis. The lidar scanning capability will provide opportunities for acquiring new data sets for atmospheric, earth resources, and oceans communities. This completed facility will also make available the opportunity to acquire simulated EOS lidar data on a near global basis. The design and construction of this unique scanning mechanism presents exciting technological challenges of maintaining the turning mirror optical flatness during scanning while exposed to extreme temperatures, ambient pressures, aircraft vibrations, etc.

  13. Large Scale Nanolaminate Deformable Mirror

    SciTech Connect

    Papavasiliou, A; Olivier, S; Barbee, T; Miles, R; Chang, K

    2005-11-30

    This work concerns the development of a technology that uses Nanolaminate foils to form light-weight, deformable mirrors that are scalable over a wide range of mirror sizes. While MEMS-based deformable mirrors and spatial light modulators have considerably reduced the cost and increased the capabilities of adaptive optic systems, there has not been a way to utilize the advantages of lithography and batch-fabrication to produce large-scale deformable mirrors. This technology is made scalable by using fabrication techniques and lithography that are not limited to the sizes of conventional MEMS devices. Like many MEMS devices, these mirrors use parallel plate electrostatic actuators. This technology replicates that functionality by suspending a horizontal piece of nanolaminate foil over an electrode by electroplated nickel posts. This actuator is attached, with another post, to another nanolaminate foil that acts as the mirror surface. Most MEMS devices are produced with integrated circuit lithography techniques that are capable of very small line widths, but are not scalable to large sizes. This technology is very tolerant of lithography errors and can use coarser, printed circuit board lithography techniques that can be scaled to very large sizes. These mirrors use small, lithographically defined actuators and thin nanolaminate foils allowing them to produce deformations over a large area while minimizing weight. This paper will describe a staged program to develop this technology. First-principles models were developed to determine design parameters. Three stages of fabrication will be described starting with a 3 x 3 device using conventional metal foils and epoxy to a 10-across all-metal device with nanolaminate mirror surfaces.

  14. Measuring Diameters Of Large Vessels

    NASA Technical Reports Server (NTRS)

    Currie, James R.; Kissel, Ralph R.; Oliver, Charles E.; Smith, Earnest C.; Redmon, John W., Sr.; Wallace, Charles C.; Swanson, Charles P.

    1990-01-01

    Computerized apparatus produces accurate results quickly. Apparatus measures diameter of tank or other large cylindrical vessel, without prior knowledge of exact location of cylindrical axis. Produces plot of inner circumference, estimate of true center of vessel, data on radius, diameter of best-fit circle, and negative and positive deviations of radius from circle at closely spaced points on circumference. Eliminates need for time-consuming and error-prone manual measurements.

  15. Large Component Removal/Disposal

    SciTech Connect

    Wheeler, D. M.

    2002-02-27

    This paper describes the removal and disposal of the large components from Maine Yankee Atomic Power Plant. The large components discussed include the three steam generators, pressurizer, and reactor pressure vessel. Two separate Exemption Requests, which included radiological characterizations, shielding evaluations, structural evaluations and transportation plans, were prepared and issued to the DOT for approval to ship these components; the first was for the three steam generators and one pressurizer, the second was for the reactor pressure vessel. Both Exemption Requests were submitted to the DOT in November 1999. The DOT approved the Exemption Requests in May and July of 2000, respectively. The steam generators and pressurizer have been removed from Maine Yankee and shipped to the processing facility. They were removed from Maine Yankee's Containment Building, loaded onto specially designed skid assemblies, transported onto two separate barges, tied down to the barges, th en shipped 2750 miles to Memphis, Tennessee for processing. The Reactor Pressure Vessel Removal Project is currently under way and scheduled to be completed by Fall of 2002. The planning, preparation and removal of these large components has required extensive efforts in planning and implementation on the part of all parties involved.

  16. Extremely Large Cusp Diamagnetic Cavities

    NASA Astrophysics Data System (ADS)

    Chen, J.; Fritz, T. A.

    2002-05-01

    Extremely large diamagnetic cavities with a size of as large as 6 Re have been observed in the dayside high-altitude cusp regions. Some of the diamagnetic cavities were independent of the IMF directions, which is unexpected by the current MHD (or ISM) models, suggesting that the cusp diamagnetic cavities are different from the magnetospheric sash, which provides a challenge to the existing MHD (or ISM) models. Associated with these cavities are ions with energies from 40 keV up to 8 MeV. The charge state distribution of these cusp cavity ions was indicative of their seed populations being a mixture of the ionospheric and the solar wind particles. The intensities of the cusp cavity energetic ions were observed to increase by as large as four orders of the magnitudes. During high solar wind pressure period on April 21, 1999, the POLAR spacecraft observed lower ion flux in the dayside high-latitude magnetosheath than that in the neighbouring cusp cavities. These observations indicate that the dayside high-altitude cusp diamagnetic cavity is a key region for transferring the solar wind energy, mass, and momentum into the Earth's magnetosphere. These energetic particles in the cusp diamagnetic cavity together with the cusp's connectivity have significant global impacts on the geospace environment research and will be shedding light on the long-standing unsolved fundamental issue about the origins of the energetic particles in the ring current and in upstream ion events.

  17. Extremely large cusp diamagnetic cavities

    NASA Astrophysics Data System (ADS)

    Chen, J.; Fritz, T.; Siscoe, G.

    Extremely large diamagnetic cavities with a size of as large as 6 Re have been observed in the dayside high-altitude cusp regions. These diamagnetic cavities are always there day by day. Some of the diamagnetic cavities have been observed in the morningside during intervals when the IMF By component was positive (duskward), suggesting that the cusp diamagnetic cavities are different from the magnetospheric sash predicted by MHD simulations. Associated with these cavities are ions with energies from 40 keV up to 8 MeV. The charge state distribution of these cusp cavity ions was indicative of their seed populations being a mixture of the ionospheric and the solar wind particles. The intensities of the cusp cavity energetic ions were observed to increase by as large as four orders of the magnitudes. These observations indicate that the dayside high-altitude cusp diamagnetic cavity is a key region for transferring the solar wind energy, mass, and momentum into the Earth's magnetosphere. These energetic particles in the cusp diamagnetic cavity together with the cusp's connectivity to the entire magnetopause may have significant global impacts on the geospace environment. They will possibly be shedding light on the long-standing unsolved fundamental issue about the origins of the energetic particles in the ring current and in the regions upstream of the subsolar magnetopause where energetic ion events frequently are observed.

  18. Deflectometric measurement of large mirrors

    NASA Astrophysics Data System (ADS)

    Olesch, Evelyn; Häusler, Gerd; Wörnlein, André; Stinzing, Friedrich; van Eldik, Christopher

    2014-06-01

    We discuss the inspection of large-sized, spherical mirror tiles by `Phase Measuring Deflectometry' (PMD). About 10 000 of such mirror tiles, each satisfying strict requirements regarding the spatial extent of the point-spread-function (PSF), are planned to be installed on the Cherenkov Telescope Array (CTA), a future ground-based instrument to observe the sky in very high energy gamma-rays. Owing to their large radii of curvature of up to 60 m, a direct PSF measurement of these mirrors with concentric geometry requires large space. We present a PMD sensor with a footprint of only 5×2×1.2 m3 that overcomes this limitation. The sensor intrinsically acquires the surface slope; the shape data are calculated by integration. In this way, the PSF can be calculated for real case scenarios, e.g., when the light source is close to infinity and off-axis. The major challenge is the calibration of the PMD sensor, specifically because the PSF data have to be reconstructed from different camera views. The calibration of the setup is described, and measurements presented and compared to results obtained with the direct approach.

  19. Large wood recruitment and transport during large floods: A review

    NASA Astrophysics Data System (ADS)

    Comiti, F.; Lucía, A.; Rickenmann, D.

    2016-09-01

    Large wood (LW) elements transported during large floods are long known to have the capacity to induce dangerous obstructions along the channel network, mostly at bridges and at hydraulic structures such as weirs. However, our current knowledge of wood transport dynamics during high-magnitude flood events is still very scarce, mostly because these are (locally) rare and thus unlikely to be directly monitored. Therefore, post-event surveys are invaluable ways to get insights (although indirectly) on LW recruitment processes, transport distance, and factors inducing LW deposition - all aspects that are crucial for the proper management of river basins related to flood hazard mitigation. This paper presents a review of the (quite limited) literature available on LW transport during large floods, drawing extensively on the authors' own experience in mountain and piedmont rivers, published and unpublished. The overall picture emerging from these studies points to a high, catchment-specific variability in all the different processes affecting LW dynamics during floods. Specifically, in the LW recruitment phase, the relative floodplain (bank erosion) vs. hillslope (landslide and debris flows) contribution in mountain rivers varies substantially, as it relates to the extent of channel widening (which depends on many variables itself) but also to the hillslope-channel connectivity of LW mobilized on the slopes. As to the LW transport phase within the channel network, it appears to be widely characterized by supply-limited conditions; whereby LW transport rates (and thus volumes) are ultimately constrained by the amount of LW that is made available to the flow. Indeed, LW deposition during floods was mostly (in terms of volume) observed at artificial structures (bridges) in all the documented events. This implies that the estimation of LW recruitment and the assessment of clogging probabilities for each structure (for a flood event of given magnitude) are the most important

  20. Large-bore pipe decontamination

    SciTech Connect

    Ebadian, M.A.

    1998-01-01

    The decontamination and decommissioning (D and D) of 1200 buildings within the US Department of Energy-Office of Environmental Management (DOE-EM) Complex will require the disposition of miles of pipe. The disposition of large-bore pipe, in particular, presents difficulties in the area of decontamination and characterization. The pipe is potentially contaminated internally as well as externally. This situation requires a system capable of decontaminating and characterizing both the inside and outside of the pipe. Current decontamination and characterization systems are not designed for application to this geometry, making the direct disposal of piping systems necessary in many cases. The pipe often creates voids in the disposal cell, which requires the pipe to be cut in half or filled with a grout material. These methods are labor intensive and costly to perform on large volumes of pipe. Direct disposal does not take advantage of recycling, which could provide monetary dividends. To facilitate the decontamination and characterization of large-bore piping and thereby reduce the volume of piping required for disposal, a detailed analysis will be conducted to document the pipe remediation problem set; determine potential technologies to solve this remediation problem set; design and laboratory test potential decontamination and characterization technologies; fabricate a prototype system; provide a cost-benefit analysis of the proposed system; and transfer the technology to industry. This report summarizes the activities performed during fiscal year 1997 and describes the planned activities for fiscal year 1998. Accomplishments for FY97 include the development of the applicable and relevant and appropriate regulations, the screening of decontamination and characterization technologies, and the selection and initial design of the decontamination system.

  1. Radiosurgery for Large Brain Metastases

    SciTech Connect

    Han, Jung Ho; Kim, Dong Gyu; Chung, Hyun-Tai; Paek, Sun Ha; Park, Chul-Kee; Jung, Hee-Won

    2012-05-01

    Purpose: To determine the efficacy and safety of radiosurgery in patients with large brain metastases treated with radiosurgery. Patients and Methods: Eighty patients with large brain metastases (>14 cm{sup 3}) were treated with radiosurgery between 1998 and 2009. The mean age was 59 {+-} 11 years, and 49 (61.3%) were men. Neurologic symptoms were identified in 77 patients (96.3%), and 30 (37.5%) exhibited a dependent functional status. The primary disease was under control in 36 patients (45.0%), and 44 (55.0%) had a single lesion. The mean tumor volume was 22.4 {+-} 8.8 cm{sup 3}, and the mean marginal dose prescribed was 13.8 {+-} 2.2 Gy. Results: The median survival time from radiosurgery was 7.9 months (95% confidence interval [CI], 5.343-10.46), and the 1-year survival rate was 39.2%. Functional improvement within 1-4 months or the maintenance of the initial independent status was observed in 48 (60.0%) and 20 (25.0%) patients after radiosurgery, respectively. Control of the primary disease, a marginal dose of {>=}11 Gy, and a tumor volume {>=}26 cm{sup 3} were significantly associated with overall survival (hazard ratio, 0.479; p = .018; 95% CI, 0.261-0.880; hazard ratio, 0.350; p = .004; 95% CI, 0.171-0.718; hazard ratio, 2.307; p = .006; 95% CI, 1.274-4.180, respectively). Unacceptable radiation-related toxicities (Radiation Toxicity Oncology Group central nervous system toxicity Grade 3, 4, and 5 in 7, 6, and 2 patients, respectively) developed in 15 patients (18.8%). Conclusion: Radiosurgery seems to have a comparable efficacy with surgery for large brain metastases. However, the rate of radiation-related toxicities after radiosurgery should be considered when deciding on a treatment modality.

  2. Challenges for Large Scale Simulations

    NASA Astrophysics Data System (ADS)

    Troyer, Matthias

    2010-03-01

    With computational approaches becoming ubiquitous the growing impact of large scale computing on research influences both theoretical and experimental work. I will review a few examples in condensed matter physics and quantum optics, including the impact of computer simulations in the search for supersolidity, thermometry in ultracold quantum gases, and the challenging search for novel phases in strongly correlated electron systems. While only a decade ago such simulations needed the fastest supercomputers, many simulations can now be performed on small workstation clusters or even a laptop: what was previously restricted to a few experts can now potentially be used by many. Only part of the gain in computational capabilities is due to Moore's law and improvement in hardware. Equally impressive is the performance gain due to new algorithms - as I will illustrate using some recently developed algorithms. At the same time modern peta-scale supercomputers offer unprecedented computational power and allow us to tackle new problems and address questions that were impossible to solve numerically only a few years ago. While there is a roadmap for future hardware developments to exascale and beyond, the main challenges are on the algorithmic and software infrastructure side. Among the problems that face the computational physicist are: the development of new algorithms that scale to thousands of cores and beyond, a software infrastructure that lifts code development to a higher level and speeds up the development of new simulation programs for large scale computing machines, tools to analyze the large volume of data obtained from such simulations, and as an emerging field provenance-aware software that aims for reproducibility of the complete computational workflow from model parameters to the final figures. Interdisciplinary collaborations and collective efforts will be required, in contrast to the cottage-industry culture currently present in many areas of computational

  3. The Large Synoptic Survey Telescope

    NASA Astrophysics Data System (ADS)

    Axelrod, T. S.

    2006-07-01

    The Large Synoptic Survey Telescope (LSST) is an 8.4 meter telescope with a 10 square degree field degree field and a 3 Gigapixel imager, planned to be on-sky in 2012. It is a dedicated all-sky survey instrument, with several complementary science missions. These include understanding dark energy through weak lensing and supernovae; exploring transients and variable objects; creating and maintaining a solar system map, with particular emphasis on potentially hazardous objects; and increasing the precision with which we understand the structure of the Milky Way. The instrument operates continuously at a rapid cadence, repetitively scanning the visible sky every few nights. The data flow rates from LSST are larger than those from current surveys by roughly a factor of 1000: A few GB/night are typical today. LSST will deliver a few TB/night. From a computing hardware perspective, this factor of 1000 can be dealt with easily in 2012. The major issues in designing the LSST data management system arise from the fact that the number of people available to critically examine the data will not grow from current levels. This has a number of implications. For example, every large imaging survey today is resigned to the fact that their image reduction pipelines fail at some significant rate. Many of these failures are dealt with by rerunning the reduction pipeline under human supervision, with carefully ``tweaked'' parameters to deal with the original problem. For LSST, this will no longer be feasible. The problem is compounded by the fact that the processing must of necessity occur on clusters with large numbers of CPU's and disk drives, and with some components connected by long-haul networks. This inevitably results in a significant rate of hardware component failures, which can easily lead to further software failures. Both hardware and software failures must be seen as a routine fact of life rather than rare exceptions to normality.

  4. LHC: The Large Hadron Collider

    SciTech Connect

    Lincoln, Don

    2015-03-04

    The Large Hadron Collider (or LHC) is the world’s most powerful particle accelerator. In 2012, scientists used data taken by it to discover the Higgs boson, before pausing operations for upgrades and improvements. In the spring of 2015, the LHC will return to operations with 163% the energy it had before and with three times as many collisions per second. It’s essentially a new and improved version of itself. In this video, Fermilab’s Dr. Don Lincoln explains both some of the absolutely amazing scientific and engineering properties of this modern scientific wonder.

  5. Uncertainties in large space systems

    NASA Technical Reports Server (NTRS)

    Fuh, Jon-Shen

    1988-01-01

    Uncertainties of a large space system (LSS) can be deterministic or stochastic in nature. The former may result in, for example, an energy spillover problem by which the interaction between unmodeled modes and controls may cause system instability. The stochastic uncertainties are responsible for mode localization and estimation errors, etc. We will address the effects of uncertainties on structural model formulation, use of available test data to verify and modify analytical models before orbiting, and how the system model can be further improved in the on-orbit environment.

  6. Microfluidic large-scale integration.

    PubMed

    Thorsen, Todd; Maerkl, Sebastian J; Quake, Stephen R

    2002-10-18

    We developed high-density microfluidic chips that contain plumbing networks with thousands of micromechanical valves and hundreds of individually addressable chambers. These fluidic devices are analogous to electronic integrated circuits fabricated using large-scale integration. A key component of these networks is the fluidic multiplexor, which is a combinatorial array of binary valve patterns that exponentially increases the processing power of a network by allowing complex fluid manipulations with a minimal number of inputs. We used these integrated microfluidic networks to construct the microfluidic analog of a comparator array and a microfluidic memory storage device whose behavior resembles random-access memory. PMID:12351675

  7. Large spin systematics in CFT

    NASA Astrophysics Data System (ADS)

    Alday, Luis F.; Bissi, Agnese; Lukowski, Tomasz

    2015-11-01

    Using conformal field theory (CFT) arguments we derive an infinite number of constraints on the large spin expansion of the anomalous dimensions and structure constants of higher spin operators. These arguments rely only on analyticity, unitarity, crossing-symmetry and the structure of the conformal partial wave expansion. We obtain results for both, perturbative CFT to all order in the perturbation parameter, as well as non-perturbatively. For the case of conformal gauge theories this provides a proof of the reciprocity principle to all orders in perturbation theory and provides a new "reciprocity" principle for structure constants. We argue that these results extend also to non-conformal theories.

  8. Large block test status report

    SciTech Connect

    Wilder, D.G.; Lin, W.; Blair, S.C.

    1997-08-26

    This report is intended to serve as a status report, which essentially transmits the data that have been collected to date on the Large Block Test (LBT). The analyses of data will be performed during FY98, and then a complete report will be prepared. This status report includes introductory material that is not needed merely to transmit data but is available at this time and therefore included. As such, this status report will serve as the template for the future report, and the information is thus preserved.

  9. the Large Aperture GRB Observatory

    SciTech Connect

    Bertou, Xavier

    2009-04-30

    The Large Aperture GRB Observatory (LAGO) aims at the detection of high energy photons from Gamma Ray Bursts (GRB) using the single particle technique (SPT) in ground based water Cherenkov detectors (WCD). To reach a reasonable sensitivity, high altitude mountain sites have been selected in Mexico (Sierra Negra, 4550 m a.s.l.), Bolivia (Chacaltaya, 5300 m a.s.l.) and Venezuela (Merida, 4765 m a.s.l.). We report on the project progresses and the first operation at high altitude, search for bursts in 6 months of preliminary data, as well as search for signal at ground level when satellites report a burst.

  10. Radiolabeled Monoclonal Antibody With or Without Peripheral Stem Cell Transplantation in Treating Children With Recurrent or Refractory Lymphoma

    ClinicalTrials.gov

    2013-01-16

    AIDS-related Peripheral/Systemic Lymphoma; AIDS-related Primary CNS Lymphoma; Post-transplant Lymphoproliferative Disorder; Recurrent Childhood Large Cell Lymphoma; Recurrent Childhood Lymphoblastic Lymphoma; Recurrent Childhood Small Noncleaved Cell Lymphoma; Recurrent/Refractory Childhood Hodgkin Lymphoma

  11. Large-mode enhancement cavities.

    PubMed

    Carstens, Henning; Holzberger, Simon; Kaster, Jan; Weitenberg, Johannes; Pervak, Volodymyr; Apolonski, Alexander; Fill, Ernst; Krausz, Ferenc; Pupeza, Ioachim

    2013-05-01

    In passive enhancement cavities the achievable power level is limited by mirror damage. Here, we address the design of robust optical resonators with large spot sizes on all mirrors, a measure that promises to mitigate this limitation by decreasing both the intensity and the thermal gradient on the mirror surfaces. We introduce a misalignment sensitivity metric to evaluate the robustness of resonator designs. We identify the standard bow-tie resonator operated close to the inner stability edge as the most robust large-mode cavity and implement this cavity with two spherical mirrors with 600 mm radius of curvature, two plane mirrors and a round trip length of 1.2 m, demonstrating a stable power enhancement of near-infrared laser light by a factor of 2000. Beam radii of 5.7 mm × 2.6 mm (sagittal × tangential 1/e(2) intensity radius) on all mirrors are obtained. We propose a simple all-reflective ellipticity compensation scheme. This will enable a significant increase of the attainable power and intensity levels in enhancement cavities. PMID:23670017

  12. Large aperture diffractive space telescope

    DOEpatents

    Hyde, Roderick A.

    2001-01-01

    A large (10's of meters) aperture space telescope including two separate spacecraft--an optical primary objective lens functioning as a magnifying glass and an optical secondary functioning as an eyepiece. The spacecraft are spaced up to several kilometers apart with the eyepiece directly behind the magnifying glass "aiming" at an intended target with their relative orientation determining the optical axis of the telescope and hence the targets being observed. The objective lens includes a very large-aperture, very-thin-membrane, diffractive lens, e.g., a Fresnel lens, which intercepts incoming light over its full aperture and focuses it towards the eyepiece. The eyepiece has a much smaller, meter-scale aperture and is designed to move along the focal surface of the objective lens, gathering up the incoming light and converting it to high quality images. The positions of the two space craft are controlled both to maintain a good optical focus and to point at desired targets which may be either earth bound or celestial.

  13. How Large Asexual Populations Adapt

    NASA Astrophysics Data System (ADS)

    Desai, Michael

    2007-03-01

    We often think of beneficial mutations as being rare, and of adaptation as a sequence of selected substitutions: a beneficial mutation occurs, spreads through a population in a selective sweep, then later another beneficial mutation occurs, and so on. This simple picture is the basis for much of our intuition about adaptive evolution, and underlies a number of practical techniques for analyzing sequence data. Yet many large and mostly asexual populations -- including a wide variety of unicellular organisms and viruses -- live in a very different world. In these populations, beneficial mutations are common, and frequently interfere or cooperate with one another as they all attempt to sweep simultaneously. This radically changes the way these populations adapt: rather than an orderly sequence of selective sweeps, evolution is a constant swarm of competing and interfering mutations. I will describe some aspects of these dynamics, including why large asexual populations cannot evolve very quickly and the character of the diversity they maintain. I will explain how this changes our expectations of sequence data, how sex can help a population adapt, and the potential role of ``mutator'' phenotypes with abnormally high mutation rates. Finally, I will discuss comparisons of these predictions with evolution experiments in laboratory yeast populations.

  14. Large amplitude drop shape oscillations

    NASA Technical Reports Server (NTRS)

    Trinh, E. H.; Wang, T. G.

    1982-01-01

    An experimental study of large amplitude drop shape oscillation was conducted in immiscible liquids systems and with levitated free liquid drops in air. In liquid-liquid systems the results indicate the existence of familiar characteristics of nonlinear phenomena. The resonance frequency of the fundamental quadrupole mode of stationary, low viscosity Silicone oil drops acoustically levitated in water falls to noticeably low values as the amplitude of oscillation is increased. A typical, experimentally determined relative frequency decrease of a 0.5 cubic centimeters drop would be about 10% when the maximum deformed shape is characterized by a major to minor axial ratio of 1.9. On the other hand, no change in the fundamental mode frequency could be detected for 1 mm drops levitated in air. The experimental data for the decay constant of the quadrupole mode of drops immersed in a liquid host indicate a slight increase for larger oscillation amplitudes. A qualitative investigation of the internal fluid flows for such drops revealed the existence of steady internal circulation within drops oscillating in the fundamental and higher modes. The flow field configuration in the outer host liquid is also significantly altered when the drop oscillation amplitude becomes large.

  15. Electron Collisions with Large Molecules

    NASA Astrophysics Data System (ADS)

    McKoy, Vincent

    2006-10-01

    In recent years, interest in electron-molecule collisions has increasingly shifted to large molecules. Applications within the semiconductor industry, for example, require electron collision data for molecules such as perfluorocyclobutane, while almost all biological applications involve macromolecules such as DNA. A significant development in recent years has been the realization that slow electrons can directly damage DNA. This discovery has spurred studies of low-energy collisions with the constituents of DNA, including the bases, deoxyribose, the phosphate, and larger moieties assembled from them. In semiconductor applications, a key goal is development of electron cross section sets for plasma chemistry modeling, while biological studies are largely focused on understanding the role of localized resonances in inducing DNA strand breaks. Accurate calculations of low-energy electron collisions with polyatomic molecules are computationally demanding because of the low symmetry and inherent many-electron nature of the problem; moreover, the computational requirements scale rapidly with the size of the molecule. To pursue such studies, we have adapted our computational procedure, known as the Schwinger multichannel method, to run efficiently on highly parallel computers. In this talk, we will present some of our recent results for fluorocarbon etchants used in the semiconductor industry and for constituents of DNA and RNA. In collaboration with Carl Winstead, California Institute of Technology.

  16. Large phased-array radars

    SciTech Connect

    Brookner, D.E.

    1988-12-15

    Large phased-array radars can play a very important part in arms control. They can be used to determine the number of RVs being deployed, the type of targeting of the RVs (the same or different targets), the shape of the deployed objects, and possibly the weight and yields of the deployed RVs. They can provide this information at night as well as during the day and during rain and cloud covered conditions. The radar can be on the ground, on a ship, in an airplane, or space-borne. Airborne and space-borne radars can provide high resolution map images of the ground for reconnaissance, of anti-ballistic missile (ABM) ground radar installations, missile launch sites, and tactical targets such as trucks and tanks. The large ground based radars can have microwave carrier frequencies or be at HF (high frequency). For a ground-based HF radar the signal is reflected off the ionosphere so as to provide over-the-horizon (OTH) viewing of targets. OTH radars can potentially be used to monitor stealth targets and missile traffic.

  17. Mesoscale Ocean Large Eddy Simulations

    NASA Astrophysics Data System (ADS)

    Pearson, Brodie; Fox-Kemper, Baylor; Bachman, Scott; Bryan, Frank

    2015-11-01

    The highest resolution global climate models (GCMs) can now resolve the largest scales of mesoscale dynamics in the ocean. This has the potential to increase the fidelity of GCMs. However, the effects of the smallest, unresolved, scales of mesoscale dynamics must still be parametrized. One such family of parametrizations are mesoscale ocean large eddy simulations (MOLES), but the effects of including MOLES in a GCM are not well understood. In this presentation, several MOLES schemes are implemented in a mesoscale-resolving GCM (CESM), and the resulting flow is compared with that produced by more traditional sub-grid parametrizations. Large eddy simulation (LES) is used to simulate flows where the largest scales of turbulent motion are resolved, but the smallest scales are not resolved. LES has traditionally been used to study 3D turbulence, but recently it has also been applied to idealized 2D and quasi-geostrophic (QG) turbulence. The MOLES presented here are based on 2D and QG LES schemes.

  18. Histotripsy Liquefaction of Large Hematomas.

    PubMed

    Khokhlova, Tatiana D; Monsky, Wayne L; Haider, Yasser A; Maxwell, Adam D; Wang, Yak-Nam; Matula, Thomas J

    2016-07-01

    Intra- and extra-muscular hematomas result from repetitive injury as well as sharp and blunt limb trauma. The clinical consequences can be serious, including debilitating pain and functional deficit. There are currently no short-term treatment options for large hematomas, only lengthy conservative treatment. The goal of this work was to evaluate the feasibility of a high intensity focused ultrasound (HIFU)-based technique, termed histotripsy, for rapid (within a clinically relevant timeframe of 15-20 min) liquefaction of large volume (up to 20 mL) extra-vascular hematomas for subsequent fine-needle aspiration. Experiments were performed using in vitro extravascular hematoma phantoms-fresh bovine blood poured into 50 mL molds and allowed to clot. The resulting phantoms were treated by boiling histotripsy (BH), cavitation histotripsy (CH) or a combination in a degassed water tank under ultrasound guidance. Two different transducers operating at 1 MHz and 1.5 MHz with f-number = 1 were used. The liquefied lysate was aspirated and analyzed by histology and sized in a Coulter Counter. The peak instantaneous power to achieve BH was lower than (at 1.5 MHz) or equal to (at 1 MHz) that which was required to initiate CH. Under the same exposure duration, BH-induced cavities were one and a half to two times larger than the CH-induced cavities, but the CH-induced cavities were more regularly shaped, facilitating easier aspiration. The lysates contained a small amount of debris larger than 70 μm, and 99% of particulates were smaller than 10 μm. A combination treatment of BH (for initial debulking) and CH (for liquefaction of small residual fragments) yielded 20 mL of lysate within 17.5 minutes of treatment and was found to be most optimal for liquefaction of large extravascular hematomas. PMID:27126244

  19. Large Space Antenna Systems Technology, 1984

    NASA Technical Reports Server (NTRS)

    Boyer, W. J. (Compiler)

    1985-01-01

    Mission applications for large space antenna systems; large space antenna structural systems; materials and structures technology; structural dynamics and control technology, electromagnetics technology, large space antenna systems and the Space Station; and flight test and evaluation were examined.

  20. Large Aperture Electrostatic Dust Detector

    SciTech Connect

    C.H. Skinner, R. Hensley, and A.L Roquemore

    2007-10-09

    Diagnosis and management of dust inventories generated in next-step magnetic fusion devices is necessary for their safe operation. A novel electrostatic dust detector, based on a fine grid of interlocking circuit traces biased to 30 or 50 ν has been developed for the detection of dust particles on remote surfaces in air and vacuum environments. Impinging dust particles create a temporary short circuit and the resulting current pulse is recorded by counting electronics. Up to 90% of the particles are ejected from the grid or vaporized suggesting the device may be useful for controlling dust inventories. We report measurements of the sensitivity of a large area (5x5 cm) detector to microgram quantities of dust particles and review its applications to contemporary tokamaks and ITER.

  1. Large area pulsed solar simulator

    NASA Technical Reports Server (NTRS)

    Kruer, Mark A. (Inventor)

    1999-01-01

    An advanced solar simulator illuminates the surface a very large solar array, such as one twenty feet by twenty feet in area, from a distance of about twenty-six feet with an essentially uniform intensity field of pulsed light of an intensity of one AMO, enabling the solar array to be efficiently tested with light that emulates the sun. Light modifiers sculpt a portion of the light generated by an electrically powered high power Xenon lamp and together with direct light from the lamp provide uniform intensity illumination throughout the solar array, compensating for the square law and cosine law reduction in direct light intensity, particularly at the corner locations of the array. At any location within the array the sum of the direct light and reflected light is essentially constant.

  2. Adaptive Optics for Large Telescopes

    SciTech Connect

    Olivier, S

    2008-06-27

    The use of adaptive optics was originally conceived by astronomers seeking to correct the blurring of images made with large telescopes due to the effects of atmospheric turbulence. The basic idea is to use a device, a wave front corrector, to adjust the phase of light passing through an optical system, based on some measurement of the spatial variation of the phase transverse to the light propagation direction, using a wave front sensor. Although the original concept was intended for application to astronomical imaging, the technique can be more generally applied. For instance, adaptive optics systems have been used for several decades to correct for aberrations in high-power laser systems. At Lawrence Livermore National Laboratory (LLNL), the world's largest laser system, the National Ignition Facility, uses adaptive optics to correct for aberrations in each of the 192 beams, all of which must be precisely focused on a millimeter scale target in order to perform nuclear physics experiments.

  3. Large scale topography of Io

    NASA Technical Reports Server (NTRS)

    Gaskell, R. W.; Synnott, S. P.

    1987-01-01

    To investigate the large scale topography of the Jovian satellite Io, both limb observations and stereographic techniques applied to landmarks are used. The raw data for this study consists of Voyager 1 images of Io, 800x800 arrays of picture elements each of which can take on 256 possible brightness values. In analyzing this data it was necessary to identify and locate landmarks and limb points on the raw images, remove the image distortions caused by the camera electronics and translate the corrected locations into positions relative to a reference geoid. Minimizing the uncertainty in the corrected locations is crucial to the success of this project. In the highest resolution frames, an error of a tenth of a pixel in image space location can lead to a 300 m error in true location. In the lowest resolution frames, the same error can lead to an uncertainty of several km.

  4. Safe handling of large animals.

    PubMed

    Grandin, T

    1999-01-01

    The major causes of accidents with cattle, horses, and other grazing animals are: panic due to fear, male dominance aggression, or the maternal aggression of a mother protecting her newborn. Danger is inherent when handling large animals. Understanding their behavior patterns improves safety, but working with animals will never be completely safe. Calm, quiet handling and non-slip flooring are beneficial. Rough handling and excessive use of electric prods increase chances of injury to both people and animals, because fearful animals may jump, kick, or rear. Training animals to voluntarily cooperate with veterinary procedures reduces stress and improves safety. Grazing animals have a herd instinct, and a lone, isolated animal can become agitated. Providing a companion animal helps keep an animal calm. PMID:10329901

  5. Biotherapies in large vessel vasculitis.

    PubMed

    Ferfar, Y; Mirault, T; Desbois, A C; Comarmond, C; Messas, E; Savey, L; Domont, F; Cacoub, P; Saadoun, D

    2016-06-01

    Giant cell arteritis (GCA) and Takayasu's arteritis (TA) are large vessel vasculitis (LVV) and aortic involvement is not uncommon in Behcet's disease (BD) and relapsing polychondritis (RP). Glucocorticosteroids are the mainstay of therapy in LVV. However, a significant proportion of patients have glucocorticoid dependance, serious side effects or refractory disease to steroids and other immunosuppressive treatments such as cyclophosphamide, azathioprine, mycophenolate mofetil and methotrexate. Recent advances in the understanding of the pathogenesis have resulted in the use of biological agents in patients with LVV. Anti-tumor necrosis factor-α drugs seem effective in patients with refractory Takayasu arteritis and vascular BD but have failed to do so in giant cell arteritis. Preliminary reports on the use of the anti-IL6-receptor antibody (tocilizumab), in LVV have been encouraging. The development of new biologic targeted therapies will probably open a promising future for patients with LVV. PMID:26883459

  6. Analysis of large urban fires

    SciTech Connect

    Kang, S.W.; Reitter, T.A.; Takata, A.N.

    1984-11-01

    Fires in urban areas caused by a nuclear burst are analyzed as a first step towards determining their smoke-generation chacteristics, which may have grave implications for global-scale climatic consequences. A chain of events and their component processes which would follow a nuclear attack are described. A numerical code is currently being developed to calculate ultimately the smoke production rate for a given attack scenario. Available models for most of the processes are incorporated into the code. Sample calculations of urban fire-development history performed in the code for an idealized uniform city are presented. Preliminary results indicate the importance of the wind, thermal radiation transmission, fuel distributions, and ignition thresholds on the urban fire spread characteristics. Future plans are to improve the existing models and develop new ones to characterize smoke production from large urban fires. 21 references, 18 figures.

  7. Intergalactic shells at large redshift

    NASA Technical Reports Server (NTRS)

    Shull, J. M.; Silk, J.

    1981-01-01

    The intergalactic shells produced by galactic explosions at large redshift, whose interiors cool by inverse Compton scattering off the cosmic background radiation, have a characteristic angular size of about 1 arcmin at peak brightness. At z values lower than 2, the shells typically have a radius of 0.5 Mpc, a velocity of about 50 km/sec, a metal abundance of about 0.0001 of cosmic values, and strong radiation in H I(Lyman-alpha), He II 304 A, and the IR fine-structure lines of C II and Si II. The predicted extragalactic background emission from many shells, strongly peaked toward the UV, sets an upper limit to the number of exploding sources at z values of about 10. Shell absorption lines of H I, C II, Si II, and Fe II, which may be seen at more recent epochs in quasar spectra, may probe otherwise invisible explosions in the early universe.

  8. Sweetwater, Texas Large N Experiment

    NASA Astrophysics Data System (ADS)

    Sumy, D. F.; Woodward, R.; Barklage, M.; Hollis, D.; Spriggs, N.; Gridley, J. M.; Parker, T.

    2015-12-01

    From 7 March to 30 April 2014, NodalSeismic, Nanometrics, and IRIS PASSCAL conducted a collaborative, spatially-dense seismic survey with several thousand nodal short-period geophones complemented by a backbone array of broadband sensors near Sweetwater, Texas. This pilot project demonstrates the efficacy of industry and academic partnerships, and leveraged a larger, commercial 3D survey to collect passive source seismic recordings to image the subsurface. This innovative deployment of a large-N mixed-mode array allows industry to explore array geometries and investigate the value of broadband recordings, while affording academics a dense wavefield imaging capability and an operational model for high volume instrument deployment. The broadband array consists of 25 continuously-recording stations from IRIS PASSCAL and Nanometrics, with an array design that maximized recording of horizontal-traveling seismic energy for surface wave analysis over the primary target area with sufficient offset for imaging objectives at depth. In addition, 2639 FairfieldNodal Zland nodes from NodalSeismic were deployed in three sub-arrays: the outlier, backbone, and active source arrays. The backbone array consisted of 292 nodes that covered the entire survey area, while the outlier array consisted of 25 continuously-recording nodes distributed at a ~3 km distance away from the survey perimeter. Both the backbone and outlier array provide valuable constraints for the passive source portion of the analysis. This project serves as a learning platform to develop best practices in the support of large-N arrays with joint industry and academic expertise. Here we investigate lessons learned from a facility perspective, and present examples of data from the various sensors and array geometries. We will explore first-order results from local and teleseismic earthquakes, and show visualizations of the data across the array. Data are archived at the IRIS DMC under stations codes XB and 1B.

  9. Large and small photovoltaic powerplants

    NASA Astrophysics Data System (ADS)

    Cormode, Daniel

    The installed base of photovoltaic power plants in the United States has roughly doubled every 1 to 2 years between 2008 and 2015. The primary economic drivers of this are government mandates for renewable power, falling prices for all PV system components, 3rd party ownership models, and a generous tariff scheme known as net-metering. Other drivers include a desire for decreasing the environmental impact of electricity generation and a desire for some degree of independence from the local electric utility. The result is that in coming years, PV power will move from being a minor niche to a mainstream source of energy. As additional PV power comes online this will create challenges for the electric grid operators. We examine some problems related to large scale adoption of PV power in the United States. We do this by first discussing questions of reliability and efficiency at the PV system level. We measure the output of a fleet of small PV systems installed at Tucson Electric Power, and we characterize the degradation of those PV systems over several years. We develop methods to predict energy output from PV systems and quantify the impact of negatives such as partial shading, inverter inefficiency and malfunction of bypass diodes. Later we characterize the variability from large PV systems, including fleets of geographically diverse utility scale power plants. We also consider the power and energy requirements needed to smooth those systems, both from the perspective of an individual system and as a fleet. Finally we report on experiments from a utility scale PV plus battery hybrid system deployed near Tucson, Arizona where we characterize the ability of this system to produce smoothly ramping power as well as production of ancillary energy services such as frequency response.

  10. Low Cost Large Space Antennas

    NASA Technical Reports Server (NTRS)

    Chmielewski, Artur B.; Freeland, Robert

    1997-01-01

    The mobile communication community could significantly benefit from the availability of low-cost, large space-deployable antennas. A new class of space structures, called inflatable deployable structures, will become an option for this industry in the near future. This new technology recently made significant progress with respect to reducing the risk of flying large inflatable structures in space. This progress can be attributed to the successful space flight of the Inflatable Antenna Experiment in May of 1996, which prompted the initiation of the NASA portion of the joint NASA/DOD coordinated Space Inflatables Program, which will develop the technology to be used in future mobile communications antennas along with other users. The NASA/DOD coordinated Space Inflatables Program was initiated in 1997 as a direct result of the Inflatable Antenna Experiment. The program adds a new NASA initiative to a substantial DOD program that involves developing a series of ground test hardware, starting with 3 meter diameter units and advancing the manufacturing techniques to fabricate a 25 meter ground demonstrator unit with surface accuracy exceeding the requirements for mobile communication applications. Simultaneously, the program will be advancing the state of the art in several important inflatable technology areas, such as developing rigidizable materials for struts and tori and investigating thin film technology issues, such as application of coatings, property measurement and materials processing and assembly techniques. A very important technology area being addressed by the program is deployment control techniques. The program will sponsor activities that will lead to understanding the effects of material strain energy release, residual air in the stowed structure, and the design of the launch restraint and release system needed to control deployment dynamics. Other technology areas directly applicable to developing inflatable mobile communication antennas in the near

  11. Large hole rotary drill performance

    SciTech Connect

    Workman, J.L.; Calder, P.N.

    1996-12-31

    Large hole rotary drilling is one of the most common methods of producing blastholes in open pit mining. Large hole drilling generally refers to diameters from 9 to 17 inch (229 to 432 mm), however a considerable amount of rotary drilling is done in diameters from 6{1/2} to 9 inch (165 to 229 mm). These smaller diameters are especially prevalent in gold mining and quarrying. Rotary drills are major mining machines having substantial capital cost. Drill bit costs can also be high, depending on the bit type and formation being drilled. To keep unit costs low the drills must perform at a high productivity level. The most important factor in rotary drilling is the penetration rate. This paper discusses the factors affecting penetration rate. An empirical factor in rotary drilling is the penetration rate. This paper discusses the factors affecting penetration rate. An empirical factor is given for calculating the penetration rate based on rock strength, pulldown weight and the RPM. The importance of using modern drill performance monitoring systems to calibrate the penetration equation for specific rock formations is discussed. Adequate air delivered to the bottom of the hole is very important to achieving maximum penetration rates. If there is insufficient bailing velocity cuttings will not be transported from the bottom of the hole rapidly enough and the penetration rate is very likely to decrease. An expression for the balancing air velocity is given. The amount by which the air velocity must exceed the balancing velocity for effective operation is discussed. The effect of altitude on compressor size is also provided.

  12. Large-Scale Information Systems

    SciTech Connect

    D. M. Nicol; H. R. Ammerlahn; M. E. Goldsby; M. M. Johnson; D. E. Rhodes; A. S. Yoshimura

    2000-12-01

    Large enterprises are ever more dependent on their Large-Scale Information Systems (LSLS), computer systems that are distinguished architecturally by distributed components--data sources, networks, computing engines, simulations, human-in-the-loop control and remote access stations. These systems provide such capabilities as workflow, data fusion and distributed database access. The Nuclear Weapons Complex (NWC) contains many examples of LSIS components, a fact that motivates this research. However, most LSIS in use grew up from collections of separate subsystems that were not designed to be components of an integrated system. For this reason, they are often difficult to analyze and control. The problem is made more difficult by the size of a typical system, its diversity of information sources, and the institutional complexities associated with its geographic distribution across the enterprise. Moreover, there is no integrated approach for analyzing or managing such systems. Indeed, integrated development of LSIS is an active area of academic research. This work developed such an approach by simulating the various components of the LSIS and allowing the simulated components to interact with real LSIS subsystems. This research demonstrated two benefits. First, applying it to a particular LSIS provided a thorough understanding of the interfaces between the system's components. Second, it demonstrated how more rapid and detailed answers could be obtained to questions significant to the enterprise by interacting with the relevant LSIS subsystems through simulated components designed with those questions in mind. In a final, added phase of the project, investigations were made on extending this research to wireless communication networks in support of telemetry applications.

  13. Large and small volcanic eruptions

    NASA Astrophysics Data System (ADS)

    Gudmundsson, Agust; Mohajeri, Nahid

    2013-04-01

    Despite great progress in volcanology in the past decades, we still cannot make reliable forecasts as to the likely size (volume, mass) of an eruption once it has started. Empirical data collected from volcanoes worldwide indicates that the volumes (or masses) of eruptive materials in volcanic eruptions are heavy-tailed. This means that most of the volumes erupted from a given magma chamber are comparatively small. Yet, the same magma chamber can, under certain conditions, squeeze out large volumes of magma. To know these conditions is of fundamental importance for forecasting the likely size of an eruption. Thermodynamics provides the basis for understanding the elastic energy available to (i) propagate an injected dyke from the chamber and to the surface to feed an eruption, and (ii) squeeze magma out of the chamber during the eruption. The elastic energy consists of two main parts: first, the strain energy stored in the volcano before magma-chamber rupture and dyke injection, and, second, the work done through displacement of the flanks of the volcano (or the margins of a rift zone) and the expansion and shrinkage of the magma chamber itself. Other forms of energy in volcanoes - thermal, seismic, kinetic - are generally important but less so for squeezing magma out of a chamber during an eruption. Here we suggest that for (basaltic) eruptions in rift zones the strain energy is partly related to minor doming above the reservoir, and partly to stretching of the rift zone before rupture. The larger the reservoir, the larger is the stored strain energy before eruption. However, for the eruption to be really large, the strain energy has to accumulate in the entire crustal segment above the reservoir and there will be additional energy input into the system during the eruption which relates to the displacements of the boundary of the rift-zone segment. This is presumably why feeder dykes commonly propagate laterally at the surface following the initial fissure

  14. Large Block Test Final Report

    SciTech Connect

    Lin, W

    2001-12-01

    This report documents the Large-Block Test (LBT) conducted at Fran Ridge near Yucca Mountain, Nevada. The LBT was a thermal test conducted on an exposed block of middle non-lithophysal Topopah Spring tuff (Tptpmn) and was designed to assist in understanding the thermal-hydrological-mechanical-chemical (THMC) processes associated with heating and then cooling a partially saturated fractured rock mass. The LBT was unique in that it was a large (3 x 3 x 4.5 m) block with top and sides exposed. Because the block was exposed at the surface, boundary conditions on five of the six sides of the block were relatively well known and controlled, making this test both easier to model and easier to monitor. This report presents a detailed description of the test as well as analyses of the data and conclusions drawn from the test. The rock block that was tested during the LBT was exposed by excavation and removal of the surrounding rock. The block was characterized and instrumented, and the sides were sealed and insulated to inhibit moisture and heat loss. Temperature on the top of the block was also controlled. The block was heated for 13 months, during which time temperature, moisture distribution, and deformation were monitored. After the test was completed and the block cooled down, a series of boreholes were drilled, and one of the heater holes was over-cored to collect samples for post-test characterization of mineralogy and mechanical properties. Section 2 provides background on the test. Section 3 lists the test objectives and describes the block site, the site configuration, and measurements made during the test. Section 3 also presents a chronology of events associated with the LBT, characterization of the block, and the pre-heat analyses of the test. Section 4 describes the fracture network contained in the block. Section 5 describes the heating/cooling system used to control the temperature in the block and presents the thermal history of the block during the test

  15. Large Volcanic Rises on Venus

    NASA Technical Reports Server (NTRS)

    Smrekar, Suzanne E.; Kiefer, Walter S.; Stofan, Ellen R.

    1997-01-01

    Large volcanic rises on Venus have been interpreted as hotspots, or the surface manifestation of mantle upwelling, on the basis of their broad topographic rises, abundant volcanism, and large positive gravity anomalies. Hotspots offer an important opportunity to study the behavior of the lithosphere in response to mantle forces. In addition to the four previously known hotspots, Atla, Bell, Beta, and western Eistla Regiones, five new probable hotspots, Dione, central Eistla, eastern Eistla, Imdr, and Themis, have been identified in the Magellan radar, gravity and topography data. These nine regions exhibit a wider range of volcano-tectonic characteristics than previously recognized for venusian hotspots, and have been classified as rift-dominated (Atla, Beta), coronae-dominated (central and eastern Eistla, Themis), or volcano-dominated (Bell, Dione, western Eistla, Imdr). The apparent depths of compensation for these regions ranges from 65 to 260 km. New estimates of the elastic thickness, using the 90 deg and order spherical harmonic field, are 15-40 km at Bell Regio, and 25 km at western Eistla Regio. Phillips et al. find a value of 30 km at Atla Regio. Numerous models of lithospheric and mantle behavior have been proposed to interpret the gravity and topography signature of the hotspots, with most studies focusing on Atla or Beta Regiones. Convective models with Earth-like parameters result in estimates of the thickness of the thermal lithosphere of approximately 100 km. Models of stagnant lid convection or thermal thinning infer the thickness of the thermal lithosphere to be 300 km or more. Without additional constraints, any of the model fits are equally valid. The thinner thermal lithosphere estimates are most consistent with the volcanic and tectonic characteristics of the hotspots. Estimates of the thermal gradient based on estimates of the elastic thickness also support a relatively thin lithosphere (Phillips et al.). The advantage of larger estimates of

  16. Anthropogenic Triggering of Large Earthquakes

    NASA Astrophysics Data System (ADS)

    Mulargia, Francesco; Bizzarri, Andrea

    2014-08-01

    The physical mechanism of the anthropogenic triggering of large earthquakes on active faults is studied on the basis of experimental phenomenology, i.e., that earthquakes occur on active tectonic faults, that crustal stress values are those measured in situ and, on active faults, comply to the values of the stress drop measured for real earthquakes, that the static friction coefficients are those inferred on faults, and that the effective triggering stresses are those inferred for real earthquakes. Deriving the conditions for earthquake nucleation as a time-dependent solution of the Tresca-Von Mises criterion applied in the framework of poroelasticity yields that active faults can be triggered by fluid overpressures < 0.1 MPa. Comparing this with the deviatoric stresses at the depth of crustal hypocenters, which are of the order of 1-10 MPa, we find that injecting in the subsoil fluids at the pressures typical of oil and gas production and storage may trigger destructive earthquakes on active faults at a few tens of kilometers. Fluid pressure propagates as slow stress waves along geometric paths operating in a drained condition and can advance the natural occurrence of earthquakes by a substantial amount of time. Furthermore, it is illusory to control earthquake triggering by close monitoring of minor ``foreshocks'', since the induction may occur with a delay up to several years.

  17. Anthropogenic triggering of large earthquakes.

    PubMed

    Mulargia, Francesco; Bizzarri, Andrea

    2014-01-01

    The physical mechanism of the anthropogenic triggering of large earthquakes on active faults is studied on the basis of experimental phenomenology, i.e., that earthquakes occur on active tectonic faults, that crustal stress values are those measured in situ and, on active faults, comply to the values of the stress drop measured for real earthquakes, that the static friction coefficients are those inferred on faults, and that the effective triggering stresses are those inferred for real earthquakes. Deriving the conditions for earthquake nucleation as a time-dependent solution of the Tresca-Von Mises criterion applied in the framework of poroelasticity yields that active faults can be triggered by fluid overpressures < 0.1 MPa. Comparing this with the deviatoric stresses at the depth of crustal hypocenters, which are of the order of 1-10 MPa, we find that injecting in the subsoil fluids at the pressures typical of oil and gas production and storage may trigger destructive earthquakes on active faults at a few tens of kilometers. Fluid pressure propagates as slow stress waves along geometric paths operating in a drained condition and can advance the natural occurrence of earthquakes by a substantial amount of time. Furthermore, it is illusory to control earthquake triggering by close monitoring of minor "foreshocks", since the induction may occur with a delay up to several years. PMID:25156190

  18. Amplification of large artificial chromosomes.

    PubMed Central

    Smith, D R; Smyth, A P; Moir, D T

    1990-01-01

    Yeast artificial chromosome cloning is an attractive technology for genomic mapping studies because very large DNA segments can be readily propagated. However, detailed analyses often require the extensive application of blotting-hybridization techniques because artificial chromosomes are normally present at only one copy per haploid genome. We have developed a cloning vector and host strain that alleviate this problem by permitting copy number amplification of artificial chromosomes. The vector includes a conditional centromere that can be turned on or off by changing the carbon source. Strong selective pressure for extra copies of the artificial chromosome can be applied by selecting for the expression of a heterologous thymidine kinase gene. When this system was used, artificial chromosomes ranging from about 100 to 600 kilobases in size were readily amplified 10- to 20-fold. The selective conditions did not induce obvious rearrangements in any of the clones tested. Reactivation of the centromere in amplified artificial chromosome clones resulted in stable maintenance of an elevated copy number for 20 generations. Applications of copy number control to various aspects of artificial chromosome analysis are addressed. Images PMID:2236036

  19. Large Scale Homing in Honeybees

    PubMed Central

    Pahl, Mario; Zhu, Hong; Tautz, Jürgen; Zhang, Shaowu

    2011-01-01

    Honeybee foragers frequently fly several kilometres to and from vital resources, and communicate those locations to their nest mates by a symbolic dance language. Research has shown that they achieve this feat by memorizing landmarks and the skyline panorama, using the sun and polarized skylight as compasses and by integrating their outbound flight paths. In order to investigate the capacity of the honeybees' homing abilities, we artificially displaced foragers to novel release spots at various distances up to 13 km in the four cardinal directions. Returning bees were individually registered by a radio frequency identification (RFID) system at the hive entrance. We found that homing rate, homing speed and the maximum homing distance depend on the release direction. Bees released in the east were more likely to find their way back home, and returned faster than bees released in any other direction, due to the familiarity of global landmarks seen from the hive. Our findings suggest that such large scale homing is facilitated by global landmarks acting as beacons, and possibly the entire skyline panorama. PMID:21602920

  20. The Mass of Large Impactors

    NASA Technical Reports Server (NTRS)

    Parisi, M. G.; Brunini, A.

    1996-01-01

    By means of a simplified dynamical model, we have computed the eccentricity change in the orbit of each giant planet, caused by a single, large impact at the end of the accretion process. In order to set an upper bound on this eccentricity change, we have considered the giant planets' present eccentricities as primordial ones. By means of this procedure, we were able to obtain an implicit relation for the impactor masses and maximum velocities. We have estimated by this method the maximum allowed mass to impact Jupiter to be approx. 1.136 x 10(exp -1), being in the case of Neptune approx. 3.99 x 10(exp -2) (expressed in units of each planet final mass). Due to the similar present eccentricities of Saturn, Uranus and Jupiter, the constraint masses and velocities of the bodies to impact them (in units of each planet final mass and velocity respectively) are almost the same for the three planets. These results are in good agreement with those obtained by Lissauer and Safronov. These bounds might be used to derive the mass distribution of planetesimals in the early solar system.

  1. Natural Selection in Large Populations

    NASA Astrophysics Data System (ADS)

    Desai, Michael

    2011-03-01

    I will discuss theoretical and experimental approaches to the evolutionary dynamics and population genetics of natural selection in large populations. In these populations, many mutations are often present simultaneously, and because recombination is limited, selection cannot act on them all independently. Rather, it can only affect whole combinations of mutations linked together on the same chromosome. Methods common in theoretical population genetics have been of limited utility in analyzing this coupling between the fates of different mutations. In the past few years it has become increasingly clear that this is a crucial gap in our understanding, as sequence data has begun to show that selection appears to act pervasively on many linked sites in a wide range of populations, including viruses, microbes, Drosophila, and humans. I will describe approaches that combine analytical tools drawn from statistical physics and dynamical systems with traditional methods in theoretical population genetics to address this problem, and describe how experiments in budding yeast can help us directly observe these evolutionary dynamics.

  2. How Large Should Whales Be?

    PubMed Central

    Clauset, Aaron

    2013-01-01

    The evolution and distribution of species body sizes for terrestrial mammals is well-explained by a macroevolutionary tradeoff between short-term selective advantages and long-term extinction risks from increased species body size, unfolding above the 2 g minimum size induced by thermoregulation in air. Here, we consider whether this same tradeoff, formalized as a constrained convection-reaction-diffusion system, can also explain the sizes of fully aquatic mammals, which have not previously been considered. By replacing the terrestrial minimum with a pelagic one, at roughly 7000 g, the terrestrial mammal tradeoff model accurately predicts, with no tunable parameters, the observed body masses of all extant cetacean species, including the 175,000,000 g Blue Whale. This strong agreement between theory and data suggests that a universal macroevolutionary tradeoff governs body size evolution for all mammals, regardless of their habitat. The dramatic sizes of cetaceans can thus be attributed mainly to the increased convective heat loss is water, which shifts the species size distribution upward and pushes its right tail into ranges inaccessible to terrestrial mammals. Under this macroevolutionary tradeoff, the largest expected species occurs where the rate at which smaller-bodied species move up into large-bodied niches approximately equals the rate at which extinction removes them. PMID:23342050

  3. Large N{sub c}

    SciTech Connect

    Jenkins, Elizabeth E.

    2009-12-17

    The 1/N{sub c} expansion of QCD with N{sub c} = 3 has been successful in explaining a wide variety of QCD phenomenology. Here I focus on the contracted spin-flavor symmetry of baryons in the large-N{sub c} limit and deviations from spin-flavor symmetry due to corrections suppressed by powers of 1/N{sub c}. Baryon masses provide an important example of the 1/N{sub c} expansion, and successful predictions of masses of heavy-quark baryons continue to be tested by experiment. The ground state charmed baryon masses have all been measured, and five of the eight ground state bottom baryon masses have been found. Results of the 1/N{sub c} expansion can aid in the discovery of the remaining bottom baryons. The brand new measurement of the {omega}{sub b}{sup -} mass by the CDF collaboration conflicts with the original D0 discovery value and is in excellent agreement with the prediction of the 1/N{sub c} expansion.

  4. Anthropogenic Triggering of Large Earthquakes

    PubMed Central

    Mulargia, Francesco; Bizzarri, Andrea

    2014-01-01

    The physical mechanism of the anthropogenic triggering of large earthquakes on active faults is studied on the basis of experimental phenomenology, i.e., that earthquakes occur on active tectonic faults, that crustal stress values are those measured in situ and, on active faults, comply to the values of the stress drop measured for real earthquakes, that the static friction coefficients are those inferred on faults, and that the effective triggering stresses are those inferred for real earthquakes. Deriving the conditions for earthquake nucleation as a time-dependent solution of the Tresca-Von Mises criterion applied in the framework of poroelasticity yields that active faults can be triggered by fluid overpressures < 0.1 MPa. Comparing this with the deviatoric stresses at the depth of crustal hypocenters, which are of the order of 1–10 MPa, we find that injecting in the subsoil fluids at the pressures typical of oil and gas production and storage may trigger destructive earthquakes on active faults at a few tens of kilometers. Fluid pressure propagates as slow stress waves along geometric paths operating in a drained condition and can advance the natural occurrence of earthquakes by a substantial amount of time. Furthermore, it is illusory to control earthquake triggering by close monitoring of minor “foreshocks”, since the induction may occur with a delay up to several years. PMID:25156190

  5. Large Angle Satellite Attitude Maneuvers

    NASA Technical Reports Server (NTRS)

    Cochran, J. E.; Junkins, J. L.

    1975-01-01

    Two methods are proposed for performing large angle reorientation maneuvers. The first method is based upon Euler's rotation theorem; an arbitrary reorientation is ideally accomplished by rotating the spacecraft about a line which is fixed in both the body and in space. This scheme has been found to be best suited for the case in which the initial and desired attitude states have small angular velocities. The second scheme is more general in that a general class of transition trajectories is introduced which, in principle, allows transfer between arbitrary orientation and angular velocity states. The method generates transition maneuvers in which the uncontrolled (free) initial and final states are matched in orientation and angular velocity. The forced transition trajectory is obtained by using a weighted average of the unforced forward integration of the initial state and the unforced backward integration of the desired state. The current effort is centered around practical validation of this second class of maneuvers. Of particular concern is enforcement of given control system constraints and methods for suboptimization by proper selection of maneuver initiation and termination times. Analogous reorientation strategies which force smooth transition in angular momentum and/or rotational energy are under consideration.

  6. Facilitating Navigation Through Large Archives

    NASA Technical Reports Server (NTRS)

    Shelton, Robert O.; Smith, Stephanie L.; Troung, Dat; Hodgson, Terry R.

    2005-01-01

    Automated Visual Access (AVA) is a computer program that effectively makes a large collection of information visible in a manner that enables a user to quickly and efficiently locate information resources, with minimal need for conventional keyword searches and perusal of complex hierarchical directory systems. AVA includes three key components: (1) a taxonomy that comprises a collection of words and phrases, clustered according to meaning, that are used to classify information resources; (2) a statistical indexing and scoring engine; and (3) a component that generates a graphical user interface that uses the scoring data to generate a visual map of resources and topics. The top level of an AVA display is a pictorial representation of an information archive. The user enters the depicted archive by either clicking on a depiction of subject area cluster, selecting a topic from a list, or entering a query into a text box. The resulting display enables the user to view candidate information entities at various levels of detail. Resources are grouped spatially by topic with greatest generality at the top layer and increasing detail with depth. The user can zoom in or out of specific sites or into greater or lesser content detail.

  7. How large should whales be?

    PubMed

    Clauset, Aaron

    2013-01-01

    The evolution and distribution of species body sizes for terrestrial mammals is well-explained by a macroevolutionary tradeoff between short-term selective advantages and long-term extinction risks from increased species body size, unfolding above the 2 g minimum size induced by thermoregulation in air. Here, we consider whether this same tradeoff, formalized as a constrained convection-reaction-diffusion system, can also explain the sizes of fully aquatic mammals, which have not previously been considered. By replacing the terrestrial minimum with a pelagic one, at roughly 7000 g, the terrestrial mammal tradeoff model accurately predicts, with no tunable parameters, the observed body masses of all extant cetacean species, including the 175,000,000 g Blue Whale. This strong agreement between theory and data suggests that a universal macroevolutionary tradeoff governs body size evolution for all mammals, regardless of their habitat. The dramatic sizes of cetaceans can thus be attributed mainly to the increased convective heat loss is water, which shifts the species size distribution upward and pushes its right tail into ranges inaccessible to terrestrial mammals. Under this macroevolutionary tradeoff, the largest expected species occurs where the rate at which smaller-bodied species move up into large-bodied niches approximately equals the rate at which extinction removes them. PMID:23342050

  8. Large Isotope Spectrometer for Astromag

    NASA Technical Reports Server (NTRS)

    Binns, W. R.; Klarmann, J.; Israel, M. H.; Garrard, T. L.; Mewaldt, R. A.; Stone, E. C.; Ormes, J. F.; Streitmatter, R. E.; Rasmussen, I. L.; Wiedenbeck, M. E.

    1990-01-01

    The Large Isotope Spectrometer for Astromag (LISA) is an experiment designed to measure the isotopic composition and energy spectra of cosmic rays for elements extending from beryllium through zinc. The overall objectives of this investigation are to study the origin and evolution of galactic matter; the acceleration, transport, and time scales of cosmic rays in the galaxy; and search for heavy antinuclei in the cosmic radiation. To achieve these objectives, the LISA experiment will make the first identifications of individual heavy cosmic ray isotopes in the energy range from about 2.5 to 4 GeV/n where relativistic time dilation effects enhance the abundances of radioactive clocks and where the effects of solar modulation and cross-section variations are minimized. It will extend high resolution measurements of individual element abundances and their energy spectra to energies of nearly 1 TeV/n, and has the potential for discovering heavy anti-nuclei which could not have been formed except in extragalactic sources.

  9. Control of large space structures

    NASA Technical Reports Server (NTRS)

    Gran, R.; Rossi, M.; Moyer, H. G.; Austin, F.

    1979-01-01

    The control of large space structures was studied to determine what, if any, limitations are imposed on the size of spacecraft which may be controlled using current control system design technology. Using a typical structure in the 35 to 70 meter size category, a control system design that used actuators that are currently available was designed. The amount of control power required to maintain the vehicle in a stabilized gravity gradient pointing orientation that also damped various structural motions was determined. The moment of inertia and mass properties of this structure were varied to verify that stability and performance were maintained. The study concludes that the structure's size is required to change by at least a factor of two before any stability problems arise. The stability margin that is lost is due to the scaling of the gravity gradient torques (the rigid body control) and as such can easily be corrected by changing the control gains associated with the rigid body control. A secondary conclusion from the study is that the control design that accommodates the structural motions (to damp them) is a little more sensitive than the design that works on attitude control of the rigid body only.

  10. Disorder in large- N theories

    NASA Astrophysics Data System (ADS)

    Aharony, Ofer; Komargodski, Zohar; Yankielowicz, Shimon

    2016-04-01

    We consider Euclidean Conformal Field Theories perturbed by quenched disorder, namely by random fluctuations in their couplings. Such theories are relevant for second-order phase transitions in the presence of impurities or other forms of disorder. Theories with quenched disorder often flow to new fixed points of the renormalization group. We begin with disorder in free field theories. Imry and Ma showed that disordered free fields can only exist for d > 4. For d > 4 we show that disorder leads to new fixed points which are not scale-invariant. We then move on to large- N theories (vector models or gauge theories in the `t Hooft limit). We compute exactly the beta function for the disorder, and the correlation functions of the disordered theory. We generalize the results of Imry and Ma by showing that such disordered theories exist only when disorder couples to operators of dimension Δ > d/4. Sometimes the disordered fixed points are not scale-invariant, and in other cases they have unconventional dependence on the disorder, including non-trivial effects due to irrelevant operators. Holography maps disorder in conformal theories to stochastic differential equations in a higher dimensional space. We use this dictionary to reproduce our field theory results. We also study the leading 1 /N corrections, both by field theory methods and by holography. These corrections are particularly important when disorder scales with the number of degrees of freedom.

  11. Chemotaxis of large granular lymphocytes

    SciTech Connect

    Pohajdak, B.; Gomez, J.; Orr, F.W.; Khalil, N.; Talgoy, M.; Greenberg, A.H.

    1986-01-01

    The hypothesis that large granular lymphocytes (LGL) are capable of directed locomotion (chemotaxis) was tested. A population of LGL isolated from discontinuous Percoll gradients migrated along concentration gradients of N-formyl-methionyl-leucyl-phenylalanine (f-MLP), casein, and C5a, well known chemoattractants for polymorphonuclear leukocytes and monocytes, as well as interferon-..beta.. and colony-stimulating factor. Interleukin 2, tuftsin, platelet-derived growth factor, and fibronectin were inactive. Migratory responses were greater in Percoll fractions with the highest lytic activity and HNK-1/sup +/ cells. The chemotactic response to f-MLP, casein, and C5a was always greater when the chemoattractant was present in greater concentration in the lower compartment of the Boyden chamber. Optimum chemotaxis was observed after a 1 hr incubation that made use of 12 ..mu..m nitrocellulose filters. LGL exhibited a high degree of nondirected locomotion when allowed to migrate for longer periods (> 2 hr), and when cultured in vitro for 24 to 72 hr in the presence or absence of IL 2 containing phytohemagluttinin-conditioned medium. LGL chemotaxis to f-MLP could be inhibited in a dose-dependent manner by the inactive structural analog CBZ-phe-met, and the RNK tumor line specifically bound f-ML(/sup 3/H)P, suggesting that LGL bear receptors for the chemotactic peptide.

  12. Large cities are less green

    NASA Astrophysics Data System (ADS)

    Oliveira, Erneson A.; Andrade, José S.; Makse, Hernán A.

    2014-02-01

    We study how urban quality evolves as a result of carbon dioxide emissions as urban agglomerations grow. We employ a bottom-up approach combining two unprecedented microscopic data on population and carbon dioxide emissions in the continental US. We first aggregate settlements that are close to each other into cities using the City Clustering Algorithm (CCA) defining cities beyond the administrative boundaries. Then, we use data on CO2 emissions at a fine geographic scale to determine the total emissions of each city. We find a superlinear scaling behavior, expressed by a power-law, between CO2 emissions and city population with average allometric exponent β = 1.46 across all cities in the US. This result suggests that the high productivity of large cities is done at the expense of a proportionally larger amount of emissions compared to small cities. Furthermore, our results are substantially different from those obtained by the standard administrative definition of cities, i.e. Metropolitan Statistical Area (MSA). Specifically, MSAs display isometric scaling emissions and we argue that this discrepancy is due to the overestimation of MSA areas. The results suggest that allometric studies based on administrative boundaries to define cities may suffer from endogeneity bias.

  13. Large optics inspection, tilting, and washing stand

    DOEpatents

    Ayers, Marion Jay; Ayers, Shannon Lee

    2012-10-09

    A large optics stand provides a risk free means of safely tilting large optics with ease and a method of safely tilting large optics with ease. The optics are supported in the horizontal position by pads. In the vertical plane the optics are supported by saddles that evenly distribute the optics weight over a large area.

  14. Large optics inspection, tilting, and washing stand

    DOEpatents

    Ayers, Marion Jay; Ayers, Shannon Lee

    2010-08-24

    A large optics stand provides a risk free means of safely tilting large optics with ease and a method of safely tilting large optics with ease. The optics are supported in the horizontal position by pads. In the vertical plane the optics are supported by saddles that evenly distribute the optics weight over a large area.

  15. The Large Synoptic Survey Telescope

    NASA Astrophysics Data System (ADS)

    Ivezic, Zeljko

    2007-05-01

    The Large Synoptic Survey Telescope (LSST) is currently by far the most ambitious proposed ground-based optical survey. With initial funding from the US National Science Foundation (NSF), Department of Energy (DOE) laboratories and private sponsors, the design and development efforts are well underway at many institutions, including top universities and leading national laboratories. The main science themes that drive the LSST system design are Dark Energy and Matter, the Solar System Inventory, Transient Optical Sky and the Milky Way Mapping. The LSST system, with its 8.4m telescope and 3,200 Megapixel camera, will be sited at Cerro Pachon in northern Chile, with the first light scheduled for 2014. In a continuous observing campaign, LSST will cover the entire available sky every three nights in two photometric bands to a depth of V=25 per visit (two 15 second exposures), with exquisitely accurate astrometry and photometry. Over the proposed survey lifetime of 10 years, each sky location would be observed about 1000 times, with the total exposure time of 8 hours distributed over six broad photometric bandpasses (ugrizY). This campaign will open a movie-like window on objects that change brightness, or move, on timescales ranging from 10 seconds to 10 years, and will produce a catalog containing over 10 billion galaxies and a similar number of stars. The survey will have a data rate of about 30 TB/night, and will collect over 60 PB of raw data over its lifetime, resulting in an incredibly rich and extensive public archive that will be a treasure trove for breakthroughs in many areas of astronomy and astrophysics.

  16. Fronts in Large Marine Ecosystems

    NASA Astrophysics Data System (ADS)

    Belkin, Igor M.; Cornillon, Peter C.; Sherman, Kenneth

    2009-04-01

    Oceanic fronts shape marine ecosystems; therefore front mapping and characterization are among the most important aspects of physical oceanography. Here we report on the first global remote sensing survey of fronts in the Large Marine Ecosystems (LME). This survey is based on a unique frontal data archive assembled at the University of Rhode Island. Thermal fronts were automatically derived with the edge detection algorithm of Cayula and Cornillon (1992, 1995, 1996) from 12 years of twice-daily, global, 9-km resolution satellite sea surface temperature (SST) fields to produce synoptic (nearly instantaneous) frontal maps, and to compute the long-term mean frequency of occurrence of SST fronts and their gradients. These synoptic and long-term maps were used to identify major quasi-stationary fronts and to derive provisional frontal distribution maps for all LMEs. Since SST fronts are typically collocated with fronts in other water properties such as salinity, density and chlorophyll, digital frontal paths from SST frontal maps can be used in studies of physical-biological correlations at fronts. Frontal patterns in several exemplary LMEs are described and compared, including those for: the East and West Bering Sea LMEs, Sea of Okhotsk LME, East China Sea LME, Yellow Sea LME, North Sea LME, East and West Greenland Shelf LMEs, Newfoundland-Labrador Shelf LME, Northeast and Southeast US Continental Shelf LMEs, Gulf of Mexico LME, and Patagonian Shelf LME. Seasonal evolution of frontal patterns in major upwelling zones reveals an order-of-magnitude growth of frontal scales from summer to winter. A classification of LMEs with regard to the origin and physics of their respective dominant fronts is presented. The proposed classification lends itself to comparative studies of frontal ecosystems.

  17. Temporal Large-Eddy Simulation

    NASA Technical Reports Server (NTRS)

    Pruett, C. D.; Thomas, B. C.

    2004-01-01

    In 1999, Stolz and Adams unveiled a subgrid-scale model for LES based upon approximately inverting (defiltering) the spatial grid-filter operator and termed .the approximate deconvolution model (ADM). Subsequently, the utility and accuracy of the ADM were demonstrated in a posteriori analyses of flows as diverse as incompressible plane-channel flow and supersonic compression-ramp flow. In a prelude to the current paper, a parameterized temporal ADM (TADM) was developed and demonstrated in both a priori and a posteriori analyses for forced, viscous Burger's flow. The development of a time-filtered variant of the ADM was motivated-primarily by the desire for a unifying theoretical and computational context to encompass direct numerical simulation (DNS), large-eddy simulation (LES), and Reynolds averaged Navier-Stokes simulation (RANS). The resultant methodology was termed temporal LES (TLES). To permit exploration of the parameter space, however, previous analyses of the TADM were restricted to Burger's flow, and it has remained to demonstrate the TADM and TLES methodology for three-dimensional flow. For several reasons, plane-channel flow presents an ideal test case for the TADM. Among these reasons, channel flow is anisotropic, yet it lends itself to highly efficient and accurate spectral numerical methods. Moreover, channel-flow has been investigated extensively by DNS, and a highly accurate data base of Moser et.al. exists. In the present paper, we develop a fully anisotropic TADM model and demonstrate its utility in simulating incompressible plane-channel flow at nominal values of Re(sub tau) = 180 and Re(sub tau) = 590 by the TLES method. The TADM model is shown to perform nearly as well as the ADM at equivalent resolution, thereby establishing TLES as a viable alternative to LES. Moreover, as the current model is suboptimal is some respects, there is considerable room to improve TLES.

  18. India's National Large Solar Telescope

    NASA Astrophysics Data System (ADS)

    Hasan, S. S.

    2012-12-01

    India's 2-m National Large Solar Telescope (NLST) is aimed primarily at carrying out observations of the solar atmosphere with high spatial and spectral resolution. A comprehensive site characterization program, that commenced in 2007, has identified two superb sites in the Himalayan region at altitudes greater than 4000-m that have extremely low water vapor content and are unaffected by monsoons. With an innovative optical design, the NLST is an on-axis Gregorian telescope with a low number of optical elements to reduce the number of reflections and yield a high throughput with low polarization. In addition, it is equipped with a high-order adaptive optics to produce close to diffraction limited performance. To control atmospheric and thermal perturbations of the observations, the telescope will function with a fully open dome, to achieve its full potential atop a 25 m tower. Given its design, NLST can also operate at night, without compromising its solar performance. The post-focus instruments include broad-band and tunable Fabry-Pérot narrow-band imaging instruments; a high resolution spectropolarimeter and an Echelle spectrograph for night time astronomy. This project is led by the Indian Institute of Astrophysics and has national and international partners. Its geographical location will fill the longitudinal gap between Japan and Europe and is expected to be the largest solar telescope with an aperture larger than 1.5 m till the ATST and EST come into operation. An international consortium has been identified to build the NLST. The facility is expected to be commissioned by 2016.

  19. Caste- and ethnicity-based inequalities in HIV/AIDS-related knowledge gap: a case of Nepal.

    PubMed

    Atteraya, Madhu; Kimm, HeeJin; Song, In Han

    2015-05-01

    Caste- and ethnicity-based inequalities are major obstacles to achieving health equity. The authors investigated whether there is any association between caste- and ethnicity-based inequalities and HIV-related knowledge within caste and ethnic populations. They used the 2011 Nepal Demographic and Health Survey, a nationally represented cross-sectional study data set. The study sample consisted of 11,273 women between 15 and 49 years of age. Univariate and logistic regression models were used to examine the relationship between caste- and ethnicity-based inequalities and HIV-related knowledge. The study sample was divided into high Hindu caste (47.9 percent), "untouchable" caste (18.4 percent), and indigenous populations (33.7 percent). Within the study sample, the high-caste population was found to have the greatest knowledge of the means by which HIV is prevented and transmitted. After controlling for socioeconomic and demographic characteristics, untouchables were the least knowledgeable. The odds ratio for incomplete knowledge about transmission among indigenous populations was 1.27 times higher than that for high Hindu castes, but there was no significant difference in knowledge of preventive measures. The findings suggest the existence of a prevailing HIV knowledge gap. This in turn suggests that appropriate steps need to be implemented to convey complete knowledge to underprivileged populations. PMID:26027418

  20. Monitoring HIV and AIDS Related Policy Reforms: A Road Map to Strengthen Policy Monitoring and Implementation in PEPFAR Partner Countries.

    PubMed

    Lane, Jeffrey; Verani, Andre; Hijazi, Mai; Hurley, Erin; Hagopian, Amy; Judice, Nicole; MacInnis, Ron; Sanford, Sallie; Zelek, Sarah; Katz, Aaron

    2016-01-01

    Achieving an AIDS-free generation will require the adoption and implementation of critical health policy reforms. However, countries with high HIV burden often have low policy development, advocacy, and monitoring capacity. This lack of capacity may be a significant barrier to achieving the AIDS-free generation goals. This manuscript describes the increased focus on policy development and implementation by the United States President's Emergency Plan for AIDS Relief (PEPFAR). It evaluates the curriculum and learning modalities used for two regional policy capacity building workshops organized around the PEPFAR Partnership Framework agreements and the Road Map for Monitoring and Implementing Policy Reforms. A total of 64 participants representing the U.S. Government, partner country governments, and civil society organizations attended the workshops. On average, participants responded that their policy monitoring skills improved and that they felt they were better prepared to monitor policy reforms three months after the workshop. When followed-up regarding utilization of the Road Map action plan, responses were mixed. Reasons cited for not making progress included an inability to meet or a lack of time, personnel, or governmental support. This lack of progress may point to a need for building policy monitoring systems in high HIV burden countries. Because the success of policy reforms cannot be measured by the mere adoption of written policy documents, monitoring the implementation of policy reforms and evaluating their public health impact is essential. In many high HIV burden countries, policy development and monitoring capacity remains weak. This lack of capacity could hinder efforts to achieve the ambitious AIDS-free generation treatment, care and prevention goals. The Road Map appears to be a useful tool for strengthening these critical capacities. PMID:26914708

  1. Retinal Detachment Associated with AIDS-Related Cytomegalovirus Retinitis: Risk Factors in a Resource-Limited Setting

    PubMed Central

    Yen, Michael; Chen, Jenny; Ausayakhun, Somsanguan; Kunavisarut, Paradee; Vichitvejpaisal, Pornpattana; Ausayakhun, Sakarin; Jirawison, Choeng; Shantha, Jessica; Holland, Gary N; Heiden, David; Margolis, Todd P; Keenan, Jeremy D

    2014-01-01

    Purpose To determine risk factors predictive of retinal detachment in patients with cytomegalovirus (CMV) retinitis in a setting with limited access to ophthalmic care. Design Case-control study. Methods Sixty-four patients with CMV retinitis and retinal detachment were identified from the Ocular Infectious Diseases and Retina Clinics at Chiang Mai University. Three control patients with CMV retinitis but no retinal detachment were selected for each case, matched by calendar date. The medical records of each patient were reviewed, with patient-level and eye-level features recorded for the clinic visit used to match cases and controls, and also for the initial clinic visit at which CMV retinitis was diagnosed. Risk factors for retinal detachment were assessed separately for each of these time points using multivariate conditional logistic regression models that included 1 eye from each patient. Results Patients with a retinal detachment were more likely than controls to have low visual acuity (OR, 1.24 per line of worse vision on the logMAR scale; 95%CI, 1.16-1.33) and bilateral disease (OR, 2.12; 95%CI, 0.92-4.90). Features present at the time of the initial diagnosis of CMV retinitis that predicted subsequent retinal detachment included bilateral disease (OR, 2.68; 95%CI, 1.18-6.08) and lesion size (OR, 2.64 per 10% increase in lesion size; 95%CI, 1.41-4.94). Conclusion Bilateral CMV retinitis and larger lesion sizes, each of which is a marker of advanced disease, were associated with subsequent retinal detachment. Earlier detection and treatment may reduce the likelihood that patients with CMV retinitis develop a retinal detachment. PMID:25448999

  2. AIDS-Related Stigmas and Safe-Sex Practices of African-American College Students: A Pilot Study.

    ERIC Educational Resources Information Center

    Chandler, Donald S., Jr.

    This study examined the safe-sex practices of African-American colleges students in light of culturally-specific beliefs that stigmatize Acquired Immune Deficiency Syndrome (AIDS) in the African-American community. A total of 21 self-selected, sexually-active African-American students (15 females and 6 males) aged 18-22 completed the AIDS…

  3. Understanding Culture and Its Influence on HIV/AIDS-Related Communication Among Minority Men Who Have Sex With Men.

    PubMed

    Basu, Ambar; Dillon, Patrick J; Romero-Daza, Nancy

    2016-11-01

    Scholarly research and government surveillance reports demonstrate that African American and Latino men who have sex with men (MSM) bear an inequitable burden of new HIV infections. Among the estimated 31,896 HIV infections attributed to male-to-male sexual contact in 2011, approximately 62% occurred in African American (38.2%) and Latino (23.5) MSM. Simultaneously, recent scholarship on minority MSM and HIV/AIDS reports a dearth of qualitative communication research that address this health issue. This manuscript reports a research study that seeks to fill this gap in health communication theory and praxis. Through in-depth interviews with 17 MSM of color, this article draws upon the culture-centered approach to demonstrate how cultural and contextual nuances, (in)access to structural resources, and participants' agentive capacity to act upon available knowledge/resources influences the ways they manage (the threat of) HIV/AIDS. PMID:27007012

  4. Measuring HIV- and AIDS-related stigma and discrimination in Nicaragua: results from a community-based study.

    PubMed

    Ugarte, William J; Högberg, Ulf; Valladares, Eliette C; Essén, Birgitta

    2013-04-01

    Psychometric properties of external HIV-related stigma and discrimination scales and their predictors were investigated. A cross-sectional community-based study was carried out among 520 participants using an ongoing health and demographic surveillance system in León, Nicaragua. Participants completed an 18-item HIV stigma scale and 19 HIV and AIDS discrimination-related statements. A factor analysis found that 15 of the 18 items in the stigma scale and 18 of the 19 items in the discrimination scale loaded clearly into five- and four-factor structures, respectively. Overall Cronbach's alpha of .81 for the HIV stigma scale and .91 for the HIV discrimination scale provided evidence of internal consistency. Hierarchical multiple linear regression analysis identified that females, rural residents, people with insufficient HIV-related transmission knowledge, those not tested for HIV, those reporting an elevated self-perception of HIV risk, and those unwilling to disclose their HIV status were associated with higher stigmatizing attitudes and higher discriminatory actions towards HIV-positive people. This is the first community-based study in Nicaragua that demonstrates that overall HIV stigma and discrimination scales were reliable and valid in a community-based sample comprised of men and women of reproductive age. Stigma and discrimination were reported high in the general population, especially among sub-groups. The findings in the current study suggest community-based strategies, including the monitoring of stigma and discrimination, and designing and implementing stigma reduction interventions, are greatly needed to reduce inequities and increase acceptance of persons with HIV. PMID:23514083

  5. Characterization of a new simian immunodeficiency virus strain in a naturally infected Pan troglodytes troglodytes chimpanzee with AIDS related symptoms

    PubMed Central

    2011-01-01

    Background Data on the evolution of natural SIV infection in chimpanzees (SIVcpz) and on the impact of SIV on local ape populations are only available for Eastern African chimpanzee subspecies (Pan troglodytes schweinfurthii), and no data exist for Central chimpanzees (Pan troglodytes troglodytes), the natural reservoir of the ancestors of HIV-1 in humans. Here, we report a case of naturally-acquired SIVcpz infection in a P.t.troglodytes chimpanzee with clinical and biological data and analysis of viral evolution over the course of infection. Results A male chimpanzee (Cam155), 1.5 years, was seized in southern Cameroon in November 2003 and screened SIV positive during quarantine. Clinical follow-up and biological analyses have been performed for 7 years and showed a significant decline of CD4 counts (1,380 cells/mm3 in 2004 vs 287 in 2009), a severe thrombocytopenia (130,000 cells/mm3 in 2004 vs 5,000 cells/mm3 in 2009), a weight loss of 21.8% from August 2009 to January 2010 (16 to 12.5 kg) and frequent periods of infections with diverse pathogens. DNA from PBMC, leftover from clinical follow-up samples collected in 2004 and 2009, was used to amplify overlapping fragments and sequence two full-length SIVcpzPtt-Cam155 genomes. SIVcpzPtt-Cam155 was phylogenetically related to other SIVcpzPtt from Cameroon (SIVcpzPtt-Cam13) and Gabon (SIVcpzPtt-Gab1). Ten molecular clones 5 years apart, spanning the V1V4 gp120 env region (1,100 bp), were obtained. Analyses of the env region showed positive selection (dN-dS >0), intra-host length variation and extensive amino acid diversity between clones, greater in 2009. Over 5 years, N-glycosylation site frequency significantly increased (p < 0.0001). Conclusions Here, we describe for the first time the clinical history and viral evolution of a naturally SIV infected P.t.troglodytes chimpanzee. The findings show an increasing viral diversity over time and suggest clinical progression to an AIDS-like disease, showing that SIVcpz can be pathogenic in its host, as previously described in P.t.schweinfurthii. Although studying the impact of SIV infection in wild apes is difficult, efforts should be made to better characterize the pathogenicity of the ancestors of HIV-1 in their natural host and to find out whether SIV infection also plays a role in ape population decline. PMID:21232091

  6. Concurrent zidovudine levels in semen and serum determined by radioimmunoassay in patients with AIDS or AIDS-related complex

    SciTech Connect

    Henry, K.; Chinnock, B.J.; Quinn, R.P.; Fletcher, C.V.; de Miranda, P.; Balfour, H.H.

    1988-05-27

    Zidovudine was present in the semen and serum of six patients with acquired immunodeficiency syndrome or the related complex who were receiving 200 mg of the drug orally every four to six hours. Mean semen zidovudine levels (as measured by a new radioimmunoassay) in samples collected 0.75 to 1.25 hours after oral dosing were 3.63 to 7.19 ..mu..mol/L. Levels in semen samples collected 3.0 to 4.5 hours after oral dosing were 1.68 to 6.43 ..mu..mol/L. These values are above the in vitro minimum inhibitory concentration for the human immunodeficiency virus type 1 (HIV-1). Mean serum concentrations at the early and late times after oral dosing were 0.22 to 3.07 ..mu..mol/L and 0.10 to 1.42 ..mu..mol/L, respectively. Ratios of semen/serum zidovudine levels ranged from 1.3 to 20.4. It is possible that a pH-dependent trapping mechanism, which has been described in the prostate for other antibiotics, was responsible for the relatively high semen levels observed.

  7. Monitoring HIV and AIDS Related Policy Reforms: A Road Map to Strengthen Policy Monitoring and Implementation in PEPFAR Partner Countries

    PubMed Central

    2016-01-01

    Achieving an AIDS-free generation will require the adoption and implementation of critical health policy reforms. However, countries with high HIV burden often have low policy development, advocacy, and monitoring capacity. This lack of capacity may be a significant barrier to achieving the AIDS-free generation goals. This manuscript describes the increased focus on policy development and implementation by the United States President’s Emergency Plan for AIDS Relief (PEPFAR). It evaluates the curriculum and learning modalities used for two regional policy capacity building workshops organized around the PEPFAR Partnership Framework agreements and the Road Map for Monitoring and Implementing Policy Reforms. A total of 64 participants representing the U.S. Government, partner country governments, and civil society organizations attended the workshops. On average, participants responded that their policy monitoring skills improved and that they felt they were better prepared to monitor policy reforms three months after the workshop. When followed-up regarding utilization of the Road Map action plan, responses were mixed. Reasons cited for not making progress included an inability to meet or a lack of time, personnel, or governmental support. This lack of progress may point to a need for building policy monitoring systems in high HIV burden countries. Because the success of policy reforms cannot be measured by the mere adoption of written policy documents, monitoring the implementation of policy reforms and evaluating their public health impact is essential. In many high HIV burden countries, policy development and monitoring capacity remains weak. This lack of capacity could hinder efforts to achieve the ambitious AIDS-free generation treatment, care and prevention goals. The Road Map appears to be a useful tool for strengthening these critical capacities. PMID:26914708

  8. HIV and AIDS Relative to Other Health, Social, and Relationship Concerns Among Low-Income Urban Women

    PubMed Central

    Carey, Michael P.; Braaten, Laura S.; Jaworski, Beth C.; Durant, Lauren E.; Forsyth, Andrew D.

    2008-01-01

    Objective To determine the priorities of low-income women regarding health, relationship, and social concerns. Method Street-intercept surveys conducted with 161 low-income urban women (M = 27 years; 85% African-American; 80% single mothers) regarding their perceptions of the threat associated with 48 health and social problems. Results Women rated AIDS as their most important health, social, or relationship concern; nearly one-half of all women indicated that they would attend risk reduction programs to learn how to avoid infection with HIV. Conclusions AIDS is perceived as a serious threat to women’s health, and that interventions to reduce risk are welcomed. PMID:10839652

  9. Systematic Review of the Effectiveness of Mass Communication Programs to Change HIV/AIDS-Related Behaviors in Developing Countries

    ERIC Educational Resources Information Center

    Bertrand, Jane T.; O'Reilly, Kevin; Denison, Julie; Anhang, Rebecca; Sweat, Michael

    2006-01-01

    This review systematically examined the effectiveness of 24 mass media interventions on changing human immunodeficiency virus (HIV)-related knowledge, attitudes and behaviors. The intervention studies were published from 1990 through 2004, reported data from developing countries and compared outcomes using (i) pre- and post-intervention data, (ii)…

  10. Examining a Financial Climate of Support: How Institutional-Level Financial Aid Relates to Teamwork, Leadership, and Critical Thinking

    ERIC Educational Resources Information Center

    Park, Julie J.; Denson, Nida; Johnson, Matthew

    2014-01-01

    Financial aid plays a critical role in college access and student success. It plays an increasingly important role as the college-going population continues to diversify and the cost of college continues to rise at both public and private institutions. In this study, the authors examined whether institutional level financial aid has any direct…

  11. The Role of Academic Discipline and Gender in High School Teachers' AIDS-Related Knowledge and Attitudes.

    ERIC Educational Resources Information Center

    Dawson, Lori J.; Chunis, Michelle L.; Smith, Danielle M.; Carboni, Anthony A.

    2001-01-01

    Surveyed 141 teachers from nine Massachusetts high schools to examine their knowledge of and attitudes toward AIDS. Results indicated a direct relationship between teachers' knowledge of HIV/AIDS and positive or supportive attitudes toward HIV/AIDS. There were significant differences based on academic discipline. Allied health teachers had…

  12. Plasma Fatty Acids in Zambian Adults with HIV/AIDS: Relation to Dietary Intake and Cardiovascular Risk Factors

    PubMed Central

    Nyirenda, Christopher K.; Kabagambe, Edmond K.; Koethe, John R.; Kiage, James N.; Chi, Benjamin H.; Musonda, Patrick; Blevins, Meridith; Bosire, Claire N.; Tsai, Michael Y.; Heimburger, Douglas C.

    2015-01-01

    Objective. To determine whether 24 hr dietary recalls (DR) are a good measure of polyunsaturated fatty acid (PUFA) intake when compared to plasma levels, and whether plasma PUFA is associated with markers of HIV/AIDS progression and cardiovascular disease (CVD) risk. Methods. In a cross-sectional study among 210 antiretroviral therapy-naïve HIV-infected adults from Lusaka, Zambia, we collected data on medical history and dietary intake using 24 hr DR. We measured fatty acids and markers of AIDS progression and CVD risk in fasting plasma collected at baseline. Results. PUFA intakes showed modest correlations with corresponding plasma levels; Spearman correlations were 0.36 (p < 0.01) for eicosapentaenoic acid and 0.21 (p = 0.005) for docosahexaenoic acid. While there were no significant associations (p > 0.05) between total plasma PUFA and C-reactive protein (CRP) or lipid levels, plasma arachidonic acid was inversely associated with CRP and triglycerides and positively associated with HDL-C, CD4+ T-cell count, and plasma albumin (p < 0.05). Plasma saturated fatty acids (SFA) were positively associated with CRP (β = 0.24; 95% CI: 0.08 to 0.40, p = 0.003) and triglycerides (β = 0.08; 95% CI: 0.03 to 0.12, p < 0.01). Conclusions. Our data suggest that a single DR is inadequate for assessing PUFA intake and that plasma arachidonic acid levels may modulate HIV/AIDS progression and CVD risk. PMID:26161268

  13. Large Alluvial Fans on Mars

    NASA Technical Reports Server (NTRS)

    Moore, Jeffrey M.; Howard, Alan D.

    2004-01-01

    Several dozen distinct alluvial fans, 10 to greater than 40 km long downslope are observed exclusively in highlands craters. Within a search region between 0 deg. and 30 deg. S, alluvial fan-containing craters were only found between 18 and 29 S, and they all occur at around plus or minus 1 km of the MOLA-defined Martian datum. Within the study area they are not randomly distributed but instead form three distinct clusters. Fans typically descend greater than 1 km from where they disgorge from their alcoves. Longitudinal profiles show that their surfaces are very slightly concave with a mean slope of 2 degrees. Many fans exhibit very long, narrow low-relief ridges radially oriented down-slope, often branching at their distal ends, suggestive of distributaries. Morphometric data for 31 fans was derived from MOLA data and compared with terrestrial fans with high-relief source areas, terrestrial low gradient alluvial ramps in inactive tectonic settings, and older Martian alluvial ramps along crater floors. The Martian alluvial fans generally fall on the same trends as the terrestrial alluvial fans, whereas the gentler Martian crater floor ramps are similar in gradient to the low relief terrestrial alluvial surfaces. For a given fan gradient, Martian alluvial fans generally have greater source basin relief than terrestrial fans in active tectonic settings. This suggests that the terrestrial source basins either yield coarser debris or have higher sediment concentrations than their Martian counterpoints. Martian fans and Basin and Range fans have steeper gradients than the older Martian alluvial ramps and terrestrial low relief alluvial surfaces, which is consistent with a supply of coarse sediment. Martian fans are relatively large and of low gradient, similar to terrestrial fluvial fans rather than debris flow fans. However, gravity scaling uncertainties make the flow regime forming Martian fans uncertain. Martian fans, at least those in Holden crater, apparently

  14. Interface structure at large supercooling

    NASA Astrophysics Data System (ADS)

    Misbah, C.; Müller-Krumbhaar, H.; Temkin, D. E.

    1991-04-01

    The front dynamics during the growth of a pure substance in the large undercooling limit including interface kinetics is analyzed. There exists a critical dimensionless undercooling Δ_s(>1) above which a planar front is linearly stable. For Δ < Δ_s the planar front is unstable against short wavenumbers k's perturbations, 01). Pour le front est instable vis-à-vis des perturbations de petit vecteur d'onde, 0

  15. Large space systems technology, 1981. [conferences

    NASA Technical Reports Server (NTRS)

    Boyer, W. J. (Compiler)

    1982-01-01

    A total systems approach including structures, analyses, controls, and antennas is presented as a cohesive, programmatic plan for large space systems. Specifically, program status, structures, materials, and analyses, and control of large space systems are addressed.

  16. Investing in a Large Stretch Press

    NASA Technical Reports Server (NTRS)

    Choate, M.; Nealson, W.; Jay, G.; Buss, W.

    1986-01-01

    Press for forming large aluminum parts from plates provides substantial economies. Study assessed advantages and disadvantages of investing in large stretch-forming press, and also developed procurement specification for press.

  17. Large Space Antenna Systems Technology, 1984

    NASA Technical Reports Server (NTRS)

    Boyer, W. J. (Compiler)

    1985-01-01

    Papers are presented which provide a comprehensive review of space missions requiring large antenna systems and of the status of key technologies required to enable these missions. Topic areas include mission applications for large space antenna systems, large space antenna structural systems, materials and structures technology, structural dynamics and control technology, electromagnetics technology, large space antenna systems and the space station, and flight test and evaluation.

  18. Large Devaluations and the Real Exchange Rate

    ERIC Educational Resources Information Center

    Burstein, Ariel; Eichenbaum, Martin; Rebelo, Sergio

    2005-01-01

    In this paper we argue that the primary force behind the large drop in real exchange rates that occurs after large devaluations is the slow adjustment in the prices of nontradable goods and services. Our empirical analysis uses data from five large devaluation episodes: Argentina (2002), Brazil (1999), Korea (1997), Mexico (1994), and Thailand…

  19. Large space systems technology, 1980, volume 1

    NASA Technical Reports Server (NTRS)

    Kopriver, F., III (Compiler)

    1981-01-01

    The technological and developmental efforts in support of the large space systems technology are described. Three major areas of interests are emphasized: (1) technology pertient to large antenna systems; (2) technology related to large space systems; and (3) activities that support both antenna and platform systems.

  20. 27 CFR 19.915 - Large plants.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Large plants. 19.915... OF THE TREASURY LIQUORS DISTILLED SPIRITS PLANTS Distilled Spirits For Fuel Use Permits § 19.915 Large plants. Any person wishing to establish a large plant shall make application for and obtain...

  1. Large N reduction on coset spaces

    SciTech Connect

    Kawai, Hikaru; Shimasaki, Shinji; Tsuchiya, Asato

    2010-04-15

    As an extension of our previous work concerning the large N reduction on group manifolds, we study the large N reduction on coset spaces. We show that large N field theories on coset spaces are described by certain corresponding matrix models. We also construct Chern-Simons-like theories on group manifolds and coset spaces, and give their reduced models.

  2. Large variable conductance heat pipe. Transverse header

    NASA Technical Reports Server (NTRS)

    Edelstein, F.

    1975-01-01

    The characteristics of gas-loaded, variable conductance heat pipes (VCHP) are discussed. The difficulties involved in developing a large VCHP header are analyzed. The construction of the large capacity VCHP is described. A research project to eliminate some of the problems involved in large capacity VCHP operation is explained.

  3. Geldanamycin Analogue in Treating Patients With Advanced Solid Tumors or Non-Hodgkin's Lymphoma

    ClinicalTrials.gov

    2013-12-13

    Extranodal Marginal Zone B-cell Lymphoma of Mucosa-associated Lymphoid Tissue; Nodal Marginal Zone B-cell Lymphoma; Non-Hodgkin Lymphoma; Recurrent Adult Burkitt Lymphoma; Recurrent Adult Diffuse Large Cell Lymphoma; Recurrent Adult Diffuse Mixed Cell Lymphoma; Recurrent Adult Diffuse Small Cleaved Cell Lymphoma; Recurrent Adult Immunoblastic Large Cell Lymphoma; Recurrent Adult Lymphoblastic Lymphoma; Recurrent Grade 1 Follicular Lymphoma; Recurrent Grade 2 Follicular Lymphoma; Recurrent Grade 3 Follicular Lymphoma; Recurrent Marginal Zone Lymphoma; Recurrent Small Lymphocytic Lymphoma; Splenic Marginal Zone Lymphoma; Stage IV Adult Burkitt Lymphoma; Stage IV Adult Diffuse Large Cell Lymphoma; Stage IV Adult Diffuse Mixed Cell Lymphoma; Stage IV Adult Diffuse Small Cleaved Cell Lymphoma; Stage IV Adult Immunoblastic Large Cell Lymphoma; Stage IV Adult Lymphoblastic Lymphoma; Stage IV Grade 1 Follicular Lymphoma; Stage IV Grade 2 Follicular Lymphoma; Stage IV Grade 3 Follicular Lymphoma; Stage IV Mantle Cell Lymphoma; Stage IV Marginal Zone Lymphoma; Stage IV Small Lymphocytic Lymphoma; Unspecified Adult Solid Tumor, Protocol Specific

  4. Large Space Systems Technology, Part 2, 1981

    NASA Technical Reports Server (NTRS)

    Boyer, W. J. (Compiler)

    1982-01-01

    Four major areas of interest are covered: technology pertinent to large antenna systems; technology related to the control of large space systems; basic technology concerning structures, materials, and analyses; and flight technology experiments. Large antenna systems and flight technology experiments are described. Design studies, structural testing results, and theoretical applications are presented with accompanying validation data. These research studies represent state-of-the art technology that is necessary for the development of large space systems. A total systems approach including structures, analyses, controls, and antennas is presented as a cohesive, programmatic plan for large space systems.

  5. Rituximab Plus Interleukin-2 in Treating Patients With Hematologic Cancer

    ClinicalTrials.gov

    2013-06-05

    B-cell Adult Acute Lymphoblastic Leukemia; Extranodal Marginal Zone B-cell Lymphoma of Mucosa-associated Lymphoid Tissue; Nodal Marginal Zone B-cell Lymphoma; Noncontiguous Stage II Adult Burkitt Lymphoma; Noncontiguous Stage II Adult Diffuse Large Cell Lymphoma; Noncontiguous Stage II Adult Diffuse Mixed Cell Lymphoma; Noncontiguous Stage II Adult Diffuse Small Cleaved Cell Lymphoma; Noncontiguous Stage II Adult Immunoblastic Large Cell Lymphoma; Noncontiguous Stage II Adult Lymphoblastic Lymphoma; Noncontiguous Stage II Grade 1 Follicular Lymphoma; Noncontiguous Stage II Grade 2 Follicular Lymphoma; Noncontiguous Stage II Grade 3 Follicular Lymphoma; Noncontiguous Stage II Mantle Cell Lymphoma; Noncontiguous Stage II Marginal Zone Lymphoma; Noncontiguous Stage II Small Lymphocytic Lymphoma; Recurrent Adult Acute Lymphoblastic Leukemia; Recurrent Adult Burkitt Lymphoma; Recurrent Adult Diffuse Large Cell Lymphoma; Recurrent Adult Diffuse Mixed Cell Lymphoma; Recurrent Adult Diffuse Small Cleaved Cell Lymphoma; Recurrent Adult Immunoblastic Large Cell Lymphoma; Recurrent Adult Lymphoblastic Lymphoma; Recurrent Grade 1 Follicular Lymphoma; Recurrent Grade 2 Follicular Lymphoma; Recurrent Grade 3 Follicular Lymphoma; Recurrent Mantle Cell Lymphoma; Recurrent Marginal Zone Lymphoma; Recurrent Small Lymphocytic Lymphoma; Splenic Marginal Zone Lymphoma; Stage III Adult Burkitt Lymphoma; Stage III Adult Diffuse Large Cell Lymphoma; Stage III Adult Diffuse Mixed Cell Lymphoma; Stage III Adult Diffuse Small Cleaved Cell Lymphoma; Stage III Adult Immunoblastic Large Cell Lymphoma; Stage III Adult Lymphoblastic Lymphoma; Stage III Grade 1 Follicular Lymphoma; Stage III Grade 2 Follicular Lymphoma; Stage III Grade 3 Follicular Lymphoma; Stage III Mantle Cell Lymphoma; Stage III Marginal Zone Lymphoma; Stage III Small Lymphocytic Lymphoma; Stage IV Adult Burkitt Lymphoma; Stage IV Adult Diffuse Large Cell Lymphoma; Stage IV Adult Diffuse Mixed Cell Lymphoma; Stage IV Adult

  6. Survey on large scale system control methods

    NASA Technical Reports Server (NTRS)

    Mercadal, Mathieu

    1987-01-01

    The problem inherent to large scale systems such as power network, communication network and economic or ecological systems were studied. The increase in size and flexibility of future spacecraft has put those dynamical systems into the category of large scale systems, and tools specific to the class of large systems are being sought to design control systems that can guarantee more stability and better performance. Among several survey papers, reference was found to a thorough investigation on decentralized control methods. Especially helpful was the classification made of the different existing approaches to deal with large scale systems. A very similar classification is used, even though the papers surveyed are somehow different from the ones reviewed in other papers. Special attention is brought to the applicability of the existing methods to controlling large mechanical systems like large space structures. Some recent developments are added to this survey.

  7. Shape control of large space structures

    NASA Technical Reports Server (NTRS)

    Hagan, M. T.

    1982-01-01

    A survey has been conducted to determine the types of control strategies which have been proposed for controlling the vibrations in large space structures. From this survey several representative control strategies were singled out for detailed analyses. The application of these strategies to a simplified model of a large space structure has been simulated. These simulations demonstrate the implementation of the control algorithms and provide a basis for a preliminary comparison of their suitability for large space structure control.

  8. Force Sensor for Large Robot Arms

    NASA Technical Reports Server (NTRS)

    Bejczy, A. K.; Primus, H. C.; Scheinman, V. D.

    1985-01-01

    Modified Maltese-cross force sensor larger and more sensitive than earlier designs. Measures inertial forces and torques exerted on large robot arms during free movement as well as those exerted by claw on manipulated objects. Large central hole of sensor allows claw drive mounted inside arm instead of perpendicular to its axis, eliminating potentially hazardous projection. Originally developed for Space Shuttle, sensor finds applications in large industrial robots.

  9. Improved Large-Field Focusing Schlieren System

    NASA Technical Reports Server (NTRS)

    Weinstein, Leonard M.

    1993-01-01

    System used to examine complicated two- and three-dimensional flows. High-brightness large-field focusing schlieren system incorporates Fresnel lens instead of glass diffuser. In system with large field of view, image may also be very large. Relay optical subsystem minifies large image while retaining all of light. Facilities candidates for use of focusing schlieren include low-speed wind and water tunnels. Heated or cooled flow tracers or injected low- or high-density tracers used to make flows visible for photographic recording.

  10. Sorafenib in Treating Patients With Metastatic or Unresectable Solid Tumors, Multiple Myeloma, or Non-Hodgkin's Lymphoma With or Without Impaired Liver or Kidney Function

    ClinicalTrials.gov

    2013-01-04

    Extranodal Marginal Zone B-cell Lymphoma of Mucosa-associated Lymphoid Tissue; Nodal Marginal Zone B-cell Lymphoma; Recurrent Adult Burkitt Lymphoma; Recurrent Adult Diffuse Large Cell Lymphoma; Recurrent Adult Diffuse Mixed Cell Lymphoma; Recurrent Adult Diffuse Small Cleaved Cell Lymphoma; Recurrent Adult Grade III Lymphomatoid Granulomatosis; Recurrent Adult Immunoblastic Large Cell Lymphoma; Recurrent Adult Lymphoblastic Lymphoma; Recurrent Grade 1 Follicular Lymphoma; Recurrent Grade 2 Follicular Lymphoma; Recurrent Grade 3 Follicular Lymphoma; Recurrent Mantle Cell Lymphoma; Recurrent Marginal Zone Lymphoma; Recurrent Small Lymphocytic Lymphoma; Refractory Multiple Myeloma; Splenic Marginal Zone Lymphoma; Stage II Multiple Myeloma; Stage III Adult Burkitt Lymphoma; Stage III Adult Diffuse Large Cell Lymphoma; Stage III Adult Diffuse Mixed Cell Lymphoma; Stage III Adult Diffuse Small Cleaved Cell Lymphoma; Stage III Adult Immunoblastic Large Cell Lymphoma; Stage III Adult Lymphoblastic Lymphoma; Stage III Grade 1 Follicular Lymphoma; Stage III Grade 2 Follicular Lymphoma; Stage III Grade 3 Follicular Lymphoma; Stage III Mantle Cell Lymphoma; Stage III Marginal Zone Lymphoma; Stage III Multiple Myeloma; Stage III Small Lymphocytic Lymphoma; Stage IV Adult Burkitt Lymphoma; Stage IV Adult Diffuse Large Cell Lymphoma; Stage IV Adult Diffuse Mixed Cell Lymphoma; Stage IV Adult Diffuse Small Cleaved Cell Lymphoma; Stage IV Adult Immunoblastic Large Cell Lymphoma; Stage IV Adult Lymphoblastic Lymphoma; Stage IV Grade 1 Follicular Lymphoma; Stage IV Grade 2 Follicular Lymphoma; Stage IV Grade 3 Follicular Lymphoma; Stage IV Mantle Cell Lymphoma; Stage IV Marginal Zone Lymphoma; Stage IV Small Lymphocytic Lymphoma; Unspecified Adult Solid Tumor, Protocol Specific; Waldenström Macroglobulinemia

  11. Collaborative Working for Large Digitisation Projects

    ERIC Educational Resources Information Center

    Yeates, Robin; Guy, Damon

    2006-01-01

    Purpose: To explore the effectiveness of large-scale consortia for disseminating local heritage via the web. To describe the creation of a large geographically based cultural heritage consortium in the South East of England and management lessons resulting from a major web site digitisation project. To encourage the improved sharing of experience…

  12. How Do People Apprehend Large Numerosities?

    ERIC Educational Resources Information Center

    Sophian, Catherine; Chu, Yun

    2008-01-01

    People discriminate remarkably well among large numerosities. These discriminations, however, need not entail numerical representation of the quantities being compared. This research evaluated the role of both non-numerical and numerical information in adult judgments of relative numerosity for large-numerosity spatial arrays. Results of…

  13. Fabrication of large ceramic electrolyte disks

    NASA Technical Reports Server (NTRS)

    Ring, S. A.

    1972-01-01

    Process for sintering compressed ceramic powders produces large ceramic disks for use as electrolytes in high-temperature electrolytic cells. Thin, strain-free uniformly dense disks as large as 30 cm squared have been fabricated by slicing ceramic slugs produced by this technique.

  14. Densifying forest biomass into large round bales

    SciTech Connect

    Fridley, J.; Burkhardt, T.H.

    1981-01-01

    A large round-bale hay baler was modified to examine the concept of baling forest biomass in large round bales. Material baled, feed orientation, and baler belt tension were varied to observe their effects on the baling process and bale density. The torque and power required to drive the baler were measured. 10 refs.

  15. Large-Scale Reform Comes of Age

    ERIC Educational Resources Information Center

    Fullan, Michael

    2009-01-01

    This article reviews the history of large-scale education reform and makes the case that large-scale or whole system reform policies and strategies are becoming increasingly evident. The review briefly addresses the pre 1997 period concluding that while the pressure for reform was mounting that there were very few examples of deliberate or…

  16. Large Lecture Format: Some Lessons Learned.

    ERIC Educational Resources Information Center

    Kryder, LeeAnne G.

    2002-01-01

    Shares some surprising results from a business communication program's recent experiment in using a large lecture format to teach an upper-division business communication course: approximately 90-95% of the students liked the large lecture format, and the quality of their communication deliverables was as good as that produced by students who took…

  17. Large-scale infrared scene projectors

    NASA Astrophysics Data System (ADS)

    Murray, Darin A.

    1999-07-01

    Large-scale infrared scene projectors, typically have unique opto-mechanical characteristics associated to their application. This paper outlines two large-scale zoom lens assemblies with different environmental and package constraints. Various challenges and their respective solutions are discussed and presented.

  18. 75 FR 73983 - Assessments, Large Bank Pricing

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-30

    ... Kapoor, Counsel, Legal Division, (202) 898-3960. Correction In proposed rule FR Doc. 2010-29138...; ] FEDERAL DEPOSIT INSURANCE CORPORATION 12 CFR Part 327 RIN 3064-AD66 Assessments, Large Bank Pricing AGENCY..., 2010, regarding Assessments, Large Bank Pricing. This correction clarifies that the comment period...

  19. 76 FR 17521 - Assessments, Large Bank Pricing

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-30

    ... Register of February 25, 2011 (76 FR 10672), regarding Assessments, Large Bank Pricing. This correction... 17th Street, NW., Washington, DC 20429. SUPPLEMENTARY INFORMATION: In FR Doc. 2011-3086, appearing on... 327 RIN 3064-AD66 Assessments, Large Bank Pricing AGENCY: Federal Deposit Insurance Corporation...

  20. The algebras of large N matrix mechanics

    SciTech Connect

    Halpern, M.B.; Schwartz, C.

    1999-09-16

    Extending early work, we formulate the large N matrix mechanics of general bosonic, fermionic and supersymmetric matrix models, including Matrix theory: The Hamiltonian framework of large N matrix mechanics provides a natural setting in which to study the algebras of the large N limit, including (reduced) Lie algebras, (reduced) supersymmetry algebras and free algebras. We find in particular a broad array of new free algebras which we call symmetric Cuntz algebras, interacting symmetric Cuntz algebras, symmetric Bose/Fermi/Cuntz algebras and symmetric Cuntz superalgebras, and we discuss the role of these algebras in solving the large N theory. Most important, the interacting Cuntz algebras are associated to a set of new (hidden!) local quantities which are generically conserved only at large N. A number of other new large N phenomena are also observed, including the intrinsic nonlocality of the (reduced) trace class operators of the theory and a closely related large N field identification phenomenon which is associated to another set (this time nonlocal) of new conserved quantities at large N.

  1. LARGE AND GREAT RIVERS: NEW ASSESSMENT TOOLS

    EPA Science Inventory

    The Ecological Exposure Research Division has been conducting research to support the development of the next generation of bioassessment and monitoring tools for large and great rivers. Focus has largely been on the development of standardized protocols for the traditional indi...

  2. Evaluating Large-Scale Interactive Radio Programmes

    ERIC Educational Resources Information Center

    Potter, Charles; Naidoo, Gordon

    2009-01-01

    This article focuses on the challenges involved in conducting evaluations of interactive radio programmes in South Africa with large numbers of schools, teachers, and learners. It focuses on the role such large-scale evaluation has played during the South African radio learning programme's development stage, as well as during its subsequent…

  3. Perception for a large deployable reflector telescope

    NASA Technical Reports Server (NTRS)

    Breckinridge, J. M.; Swanson, P. N.; Meinel, A. B.; Meinel, M. P.

    1984-01-01

    Optical science and technology concepts for a large deployable reflector for far-infrared and submillimeter astronomy from above the earth's atmosphere are discussed. Requirements given at the Asilomar Conference are reviewed. The technical challenges of this large-aperture (about 20-meter) telescope, which will be diffraction limited in the infrared, are highlighted in a brief discussion of one particular configuration.

  4. World atlas of large optical telescopes

    NASA Technical Reports Server (NTRS)

    Meszaros, S. P.

    1979-01-01

    By 1980 there will be approximately 100 large optical telescopes in the world with mirror or lens diameters of one meter (39 inches) and larger. This atlas gives information on these telescopes and shows their locations on continent-sized maps. Observatory locations considered suitable for the construction of future large telescopes are also shown.

  5. Implementing Large Projects in Software Engineering Courses

    ERIC Educational Resources Information Center

    Coppit, David

    2006-01-01

    In software engineering education, large projects are widely recognized as a useful way of exposing students to the real-world difficulties of team software development. But large projects are difficult to put into practice. First, educators rarely have additional time to manage software projects. Second, classrooms have inherent limitations that…

  6. ARPACK: Solving large scale eigenvalue problems

    NASA Astrophysics Data System (ADS)

    Lehoucq, Rich; Maschhoff, Kristi; Sorensen, Danny; Yang, Chao

    2013-11-01

    ARPACK is a collection of Fortran77 subroutines designed to solve large scale eigenvalue problems. The package is designed to compute a few eigenvalues and corresponding eigenvectors of a general n by n matrix A. It is most appropriate for large sparse or structured matrices A where structured means that a matrix-vector product w

  7. Large Eddy Simulation of a Turbulent Jet

    NASA Technical Reports Server (NTRS)

    Webb, A. T.; Mansour, Nagi N.

    2001-01-01

    Here we present the results of a Large Eddy Simulation of a non-buoyant jet issuing from a circular orifice in a wall, and developing in neutral surroundings. The effects of the subgrid scales on the large eddies have been modeled with the dynamic large eddy simulation model applied to the fully 3D domain in spherical coordinates. The simulation captures the unsteady motions of the large-scales within the jet as well as the laminar motions in the entrainment region surrounding the jet. The computed time-averaged statistics (mean velocity, concentration, and turbulence parameters) compare well with laboratory data without invoking an empirical entrainment coefficient as employed by line integral models. The use of the large eddy simulation technique allows examination of unsteady and inhomogeneous features such as the evolution of eddies and the details of the entrainment process.

  8. Generically large nongaussianity in small multifield inflation

    SciTech Connect

    Bramante, Joseph

    2015-07-07

    If forthcoming measurements of cosmic photon polarization restrict the primordial tensor-to-scalar ratio to r<0.01, small field inflation will be a principal candidate for the origin of the universe. Here we show that small multifield inflation, without the hybrid mechanism, typically results in large squeezed nongaussianity. Small multifield potentials contain multiple flat field directions, often identified with the gauge invariant field directions in supersymmetric potentials. We find that unless these field directions have equal slopes, large nongaussianity arises. After identifying relevant differences between large and small two-field potentials, we demonstrate that the latter naturally fulfill the Byrnes-Choi-Hall large nongaussianity conditions. Computations of the primordial power spectrum, spectral index, and squeezed bispectrum, reveal that small two-field models which otherwise match observed primordial perturbations, produce excludably large nongaussianity if the inflatons’ field directions have unequal slopes.

  9. Environmental effects and large space systems

    NASA Technical Reports Server (NTRS)

    Garrett, H. B.

    1981-01-01

    When planning large scale operations in space, environmental impact must be considered in addition to radiation, spacecraft charging, contamination, high power and size. Pollution of the atmosphere and space is caused by rocket effluents and by photoelectrons generated by sunlight falling on satellite surfaces even light pollution may result (the SPS may reflect so much light as to be a nuisance to astronomers). Large (100 Km 2) structures also will absorb the high energy particles that impinge on them. Altogether, these effects may drastically alter the Earth's magnetosphere. It is not clear if these alterations will in any way affect the Earth's surface climate. Large structures will also generate large plasma wakes and waves which may cause interference with communications to the vehicle. A high energy, microwave beam from the SPS will cause ionospheric turbulence, affecting UHF and VHF communications. Although none of these effects may ultimately prove critical, they must be considered in the design of large structures.

  10. Testing Large Structures in the Field

    NASA Technical Reports Server (NTRS)

    James, George; Carne, Thomas G.

    2009-01-01

    Field testing large structures creates unique challenges such as limited choices for boundary conditions and the fact that natural excitation sources cannot be removed. Several critical developments in field testing of large structures are reviewed, including: step relaxation testing which has been developed into a useful technique to apply large forces to operational systems by careful windowing; the capability of large structures testing with free support conditions which has been expanded by implementing modeling of the support structure; natural excitation which has been developed as a viable approach to field testing; and the hybrid approach which has been developed to allow forces to be estimated in operating structures. These developments have increased the ability to extract information from large structures and are highlighted in this presentation.

  11. Do large hiatal hernias affect esophageal peristalsis?

    PubMed Central

    Roman, Sabine; Kahrilas, Peter J; Kia, Leila; Luger, Daniel; Soper, Nathaniel; Pandolfino, John E

    2013-01-01

    Background & Aim Large hiatal hernias can be associated with a shortened or tortuous esophagus. We hypothesized that these anatomic changes may alter esophageal pressure topography (EPT) measurements made during high-resolution manometry (HRM). Our aim was to compare EPT measures of esophageal motility in patients with large hiatal hernias to those of patients without hernia. Methods Among 2000 consecutive clinical EPT, we identified 90 patients with large (>5 cm) hiatal hernias on endoscopy and at least 7 evaluable swallows on EPT. Within the same database a control group without hernia was selected. EPT was analyzed for lower esophageal sphincter (LES) pressure, Distal Contractile Integral (DCI), contraction amplitude, Contractile Front Velocity (CFV) and Distal Latency time (DL). Esophageal length was measured on EPT from the distal border of upper esophageal sphincter to the proximal border of the LES. EPT diagnosis was based on the Chicago Classification. Results The manometry catheter was coiled in the hernia and did not traverse the crural diaphragm in 44 patients (49%) with large hernia. Patients with large hernias had lower average LES pressures, lower DCI, slower CFV and shorter DL than patients without hernia. They also exhibited a shorter mean esophageal length. However, the distribution of peristaltic abnormalities was not different in patients with and without large hernia. Conclusions Patients with large hernias had an alteration of EPT measurements as a consequence of the associated shortened esophagus. However, the distribution of peristaltic disorders was unaffected by the presence of hernia. PMID:22508779

  12. On the distinction between large deformation and large distortion for anisotropic materials

    SciTech Connect

    BRANNON,REBECCA M.

    2000-02-24

    A motion involves large distortion if the ratios of principal stretches differ significantly from unity. A motion involves large deformation if the deformation gradient tensor is significantly different from the identity. Unfortunately, rigid rotation fits the definition of large deformation, and models that claim to be valid for large deformation are often inadequate for large distortion. An exact solution for the stress in an idealized fiber-reinforced composite is used to show that conventional large deformation representations for transverse isotropy give errant results. Possible alternative approaches are discussed.

  13. 1919 + 742 - A large double radio source

    NASA Astrophysics Data System (ADS)

    Strom, R. G.; Eckart, A.; Biermann, P.

    1985-10-01

    A 49-cm map of the source 1919 + 742 (previously catalogued as 4C74.24 and NB74.26) shows it to be a large double. Although the optical identification is unclear, there are several candidate objects near the source centroid which appear to be members of a small group of galaxies. The absence of bright identification candidates argues for a moderately distant, and hence intrinsically large (750 kpc overall size for z = 0.1) object. The spectrum between 80 and 600 MHz is determined, some intrinsic properties are derived, and these are briefly discussed in the context of other large sources.

  14. Experimental verification of a large flexible manipulator

    NASA Technical Reports Server (NTRS)

    Lee, Jac Won; Huggins, James D.; Book, Wayne J.

    1988-01-01

    A large experimental lightweight manipulator would be useful for material handling, for welding, or for ultrasonic inspection of a large structure, such as an airframe. The flexible parallel link mechanism is designed for high rigidity without increasing weight. This constrained system is analyzed by singular value decomposition of the constraint Jacobian matrix. A verification of the modeling using the assumed mode method is presented. Eigenvalues and eigenvectors of the linearized model are compared to the measured system natural frequencies and their associated mode shapes. The modeling results for large motions are compared to the time response data from the experiments. The hydraulic actuator is verified.

  15. Learning to build large structures in space

    NASA Technical Reports Server (NTRS)

    Hagler, T.; Patterson, H. G.; Nathan, C. A.

    1977-01-01

    The paper examines some of the key technologies and forms of construction know-how that will have to be developed and tested for eventual application to building large structures in space. Construction of a shuttle-tended space construction/demonstration platform would comprehensively demonstrate large structure technology, develop construction capability, and furnish a construction platform for a variety of operational large structures. Completion of this platform would lead to demonstrations of the Satellite Power System (SPS) concept, including microwave transmission, fabrication of 20-m-deep beams, conductor installation, rotary joint installation, and solar blanket installation.

  16. Experimental Simulations of Large-Scale Collisions

    NASA Technical Reports Server (NTRS)

    Housen, Kevin R.

    2002-01-01

    This report summarizes research on the effects of target porosity on the mechanics of impact cratering. Impact experiments conducted on a centrifuge provide direct simulations of large-scale cratering on porous asteroids. The experiments show that large craters in porous materials form mostly by compaction, with essentially no deposition of material into the ejecta blanket that is a signature of cratering in less-porous materials. The ratio of ejecta mass to crater mass is shown to decrease with increasing crater size or target porosity. These results are consistent with the observation that large closely-packed craters on asteroid Mathilde appear to have formed without degradation to earlier craters.

  17. Microwave sintering of large alumina bodies

    SciTech Connect

    Blake, R.D.; Katz, J.D.

    1993-05-01

    The application of microwaves as an energy source for materials processing of large alumina bodies at elevated temperatures has been limited to date. Most work has concerned itself with small laboratory samples. The nonuniformity of the microwave field within a cavity subjects large alumina bodies to areas of concentrated energy, resulting in uneven heating and subsequent cracking. Smaller bodies are not significantly affected by field nonuniformity due to their smaller mass. This work will demonstrate a method for microwave sintering of large alumina bodies while maintaining their structural integrity. Several alumina configurations were successfully sintered using a method which creates an artificial field or environment within the microwave cavity.

  18. Microwave sintering of large alumina bodies

    SciTech Connect

    Blake, R.D.; Katz, J.D.

    1993-01-01

    The application of microwaves as an energy source for materials processing of large alumina bodies at elevated temperatures has been limited to date. Most work has concerned itself with small laboratory samples. The nonuniformity of the microwave field within a cavity subjects large alumina bodies to areas of concentrated energy, resulting in uneven heating and subsequent cracking. Smaller bodies are not significantly affected by field nonuniformity due to their smaller mass. This work will demonstrate a method for microwave sintering of large alumina bodies while maintaining their structural integrity. Several alumina configurations were successfully sintered using a method which creates an artificial field or environment within the microwave cavity.

  19. Synthesis of small and large scale dynamos

    NASA Astrophysics Data System (ADS)

    Subramanian, Kandaswamy

    Using a closure model for the evolution of magnetic correlations, we uncover an interesting plausible saturated state of the small-scale fluctuation dynamo (SSD) and a novel analogy between quantum mechanical tunnelling and the generation of large-scale fields. Large scale fields develop via the α-effect, but as magnetic helicity can only change on a resistive timescale, the time it takes to organize the field into large scales increases with magnetic Reynolds number. This is very similar to the results which obtain from simulations using the full MHD equations.

  20. Efficient generation of large random networks

    NASA Astrophysics Data System (ADS)

    Batagelj, Vladimir; Brandes, Ulrik

    2005-03-01

    Random networks are frequently generated, for example, to investigate the effects of model parameters on network properties or to test the performance of algorithms. Recent interest in the statistics of large-scale networks sparked a growing demand for network generators that can generate large numbers of large networks quickly. We here present simple and efficient algorithms to randomly generate networks according to the most commonly used models. Their running time and space requirement is linear in the size of the network generated, and they are easily implemented.

  1. Optical metrology for very large convex aspheres

    NASA Astrophysics Data System (ADS)

    Burge, J. H.; Su, P.; Zhao, C.

    2008-07-01

    Telescopes with very large diameter or with wide fields require convex secondary mirrors that may be many meters in diameter. The optical surfaces for these mirrors can be manufactured to the accuracy limited by the surface metrology. We have developed metrology systems that are specifically optimized for measuring very large convex aspheric surfaces. Large aperture vibration insensitive sub-aperture Fizeau interferometer combined with stitching software give high resolution surface measurements. The global shape is corroborated with a coordinate measuring machine based on the swing arm profilometer.

  2. Very Large System Dynamics Models - Lessons Learned

    SciTech Connect

    Jacob J. Jacobson; Leonard Malczynski

    2008-10-01

    This paper provides lessons learned from developing several large system dynamics (SD) models. System dynamics modeling practice emphasize the need to keep models small so that they are manageable and understandable. This practice is generally reasonable and prudent; however, there are times that large SD models are necessary. This paper outlines two large SD projects that were done at two Department of Energy National Laboratories, the Idaho National Laboratory and Sandia National Laboratories. This paper summarizes the models and then discusses some of the valuable lessons learned during these two modeling efforts.

  3. The Amateurs' Love Affair with Large Datasets

    NASA Astrophysics Data System (ADS)

    Price, Aaron; Jacoby, S. H.; Henden, A.

    2006-12-01

    Amateur astronomers are professionals in other areas. They bring expertise from such varied and technical careers as computer science, mathematics, engineering, and marketing. These skills, coupled with an enthusiasm for astronomy, can be used to help manage the large data sets coming online in the next decade. We will show specific examples where teams of amateurs have been involved in mining large, online data sets and have authored and published their own papers in peer-reviewed astronomical journals. Using the proposed LSST database as an example, we will outline a framework for involving amateurs in data analysis and education with large astronomical surveys.

  4. Interannual Behavior of Large Regional Dust Storms

    NASA Astrophysics Data System (ADS)

    Kass, D. M.; Kleinboehl, A.; McCleese, D. J.; Schofield, J. T.; Smith, M. D.

    2014-07-01

    We examine large regional dust storms in MCS and TES retrieved temperature profiles. There is significant repeatability with three regional storms (A, B and C) each Mars year. Each type of storm is distinct seasonally and in its behavior.

  5. Large Area Synthesis of 2D Materials

    NASA Astrophysics Data System (ADS)

    Vogel, Eric

    Transition metal dichalcogenides (TMDs) have generated significant interest for numerous applications including sensors, flexible electronics, heterostructures and optoelectronics due to their interesting, thickness-dependent properties. Despite recent progress, the synthesis of high-quality and highly uniform TMDs on a large scale is still a challenge. In this talk, synthesis routes for WSe2 and MoS2 that achieve monolayer thickness uniformity across large area substrates with electrical properties equivalent to geological crystals will be described. Controlled doping of 2D semiconductors is also critically required. However, methods established for conventional semiconductors, such as ion implantation, are not easily applicable to 2D materials because of their atomically thin structure. Redox-active molecular dopants will be demonstrated which provide large changes in carrier density and workfunction through the choice of dopant, treatment time, and the solution concentration. Finally, several applications of these large-area, uniform 2D materials will be described including heterostructures, biosensors and strain sensors.

  6. A Computer Program for Clustering Large Matrices

    ERIC Educational Resources Information Center

    Koch, Valerie L.

    1976-01-01

    A Fortran V program is described derived for the Univac 1100 Series Computer for clustering into hierarchical structures large matrices, up to 1000 x 1000 and larger, of interassociations between objects. (RC)

  7. [Large articular geode cyst in rheumatoid polyarthritis].

    PubMed

    Sabri, F; Calmes, D; Muller, M J

    1989-01-01

    A case of a large bone cyst in the tibial condyle of a patient with rheumatoid arthritis is reported. The etiology and pathology are discussed, and preventive surgical treatment is recommended. PMID:2801089

  8. Large Meteor Tracked over Northeast Alabama

    NASA Video Gallery

    On the evening of May 18, NASA all-sky meteor cameras located at NASA’s Marshall Space Flight Center and at the Walker County Science Center near Chickamauga, Ga. tracked the entry of a large meteo...

  9. Large Grain Superconducting RF Cavities at DESY

    SciTech Connect

    Singer, W.; Brinkmann, A.; Ermakov, A.; Iversen, J.; Kreps, G.; Matheisen, A.; Proch, D.; Reschke, D.; Singer, X.; Spiwek, M.; Wen, H.; Brokmeier, H. G.

    2007-08-09

    The DESY R and D program on cavities fabricated from large grain niobium explores the potential of this material for the production of approx. 1000 nine-cell cavities for the European XFEL. The program investigates basic material properties, comparing large grain material to standard sheet niobium, as well as fabrication and preparation aspects. Several single-cell cavities of TESLA shape have been fabricated from large grain niobium. A gradient up to 41 MV/m at Q0 = 1.4{center_dot}1010 (TB = 2K) was measured after electropolishing. The first three large grain nine-cell cavities worldwide have been produced under contract of DESY with ACCEL Instruments Co. The first tests have shown that all three cavities reach an accelerating gradient up to 30 MV/m after BCP (Buffered Chemical Polishing) treatment, what exceeds the XFEL requirements for RF test in the vertical cryostat.

  10. Meaningful statistical analysis of large computational clusters.

    SciTech Connect

    Gentile, Ann C.; Marzouk, Youssef M.; Brandt, James M.; Pebay, Philippe Pierre

    2005-07-01

    Effective monitoring of large computational clusters demands the analysis of a vast amount of raw data from a large number of machines. The fundamental interactions of the system are not, however, well-defined, making it difficult to draw meaningful conclusions from this data, even if one were able to efficiently handle and process it. In this paper we show that computational clusters, because they are comprised of a large number of identical machines, behave in a statistically meaningful fashion. We therefore can employ normal statistical methods to derive information about individual systems and their environment and to detect problems sooner than with traditional mechanisms. We discuss design details necessary to use these methods on a large system in a timely and low-impact fashion.

  11. Bipartite Graphs of Large Clique-Width

    NASA Astrophysics Data System (ADS)

    Korpelainen, Nicholas; Lozin, Vadim V.

    Recently, several constructions of bipartite graphs of large clique-width have been discovered in the literature. In the present paper, we propose a general framework for developing such constructions and use it to obtain new results on this topic.

  12. Large-scale inhomogeneities and galaxy statistics

    NASA Technical Reports Server (NTRS)

    Schaeffer, R.; Silk, J.

    1984-01-01

    The density fluctuations associated with the formation of large-scale cosmic pancake-like and filamentary structures are evaluated using the Zel'dovich approximation for the evolution of nonlinear inhomogeneities in the expanding universe. It is shown that the large-scale nonlinear density fluctuations in the galaxy distribution due to pancakes modify the standard scale-invariant correlation function xi(r) at scales comparable to the coherence length of adiabatic fluctuations. The typical contribution of pancakes and filaments to the J3 integral, and more generally to the moments of galaxy counts in a volume of approximately (15-40 per h Mpc)exp 3, provides a statistical test for the existence of large scale inhomogeneities. An application to several recent three dimensional data sets shows that despite large observational uncertainties over the relevant scales characteristic features may be present that can be attributed to pancakes in most, but not all, of the various galaxy samples.

  13. Large-Larmor-radius interchange instability

    SciTech Connect

    Ripin, B.H.; McLean, E.A.; Manka, C.K.; Pawley, C.; Stamper, J.A.; Peyser, T.A.; Mostovych, A.N.; Grun, J.; Hassam, A.B.; Huba, J.

    1987-11-16

    We observe linear and nonlinear features of a strong plasma/magnetic field interchange Rayleigh-Taylor instability in the limit of large ion Larmor radius. The instability undergoes rapid linear growth culminating in free-streaming flute tips.

  14. Large, horizontal-axis wind turbines

    NASA Technical Reports Server (NTRS)

    Linscott, B. S.; Perkins, P.; Dennett, J. T.

    1984-01-01

    Development of the technology for safe, reliable, environmentally acceptable large wind turbines that have the potential to generate a significant amount of electricity at costs competitive with conventional electric generating systems are presented. In addition, these large wind turbines must be fully compatible with electric utility operations and interface requirements. There are several ongoing large wind system development projects and applied research efforts directed toward meeting the technology requirements for utility applications. Detailed information on these projects is provided. The Mod-O research facility and current applied research effort in aerodynamics, structural dynamics and aeroelasticity, composite and hybrid composite materials, and multiple system interaction are described. A chronology of component research and technology development for large, horizontal axis wind turbines is presented. Wind characteristics, wind turbine economics, and the impact of wind turbines on the environment are reported. The need for continued wind turbine research and technology development is explored. Over 40 references are sited and a bibliography is included.

  15. Large Space Antenna Systems Technology, part 1

    NASA Technical Reports Server (NTRS)

    Lightner, E. B. (Compiler)

    1983-01-01

    A compilation of the unclassified papers presented at the NASA Conference on Large Space Antenna Systems Technology covers the following areas: systems, structures technology, control technology, electromagnetics, and space flight test and evaluation.

  16. Large & Small: Exploring the Laws of Nature

    ERIC Educational Resources Information Center

    Creutz, E.

    1976-01-01

    Illustrates how both large entities (such as stars and galaxies) and small entities (such as fundamental particles) obey the same physical laws. Discusses quantum mechanics, Newton's laws, and general relativity. (MLH)

  17. Communication architecture for large geostationary platforms

    NASA Technical Reports Server (NTRS)

    Bond, F. E.

    1979-01-01

    Large platforms have been proposed for supporting multipurpose communication payloads to exploit economy of scale, reduce congestion in the geostationary orbit, provide interconnectivity between diverse earth stations, and obtain significant frequency reuse with large multibeam antennas. This paper addresses a specific system design, starting with traffic projections in the next two decades and discussing tradeoffs and design approaches for major components including: antennas, transponders, and switches. Other issues explored are selection of frequency bands, modulation, multiple access, switching methods, and techniques for servicing areas with nonuniform traffic demands. Three-major services are considered: a high-volume trunking system, a direct-to-user system, and a broadcast system for video distribution and similar functions. Estimates of payload weight and d.c. power requirements are presented. Other subjects treated are: considerations of equipment layout for servicing by an orbit transfer vehicle, mechanical stability requirements for the large antennas, and reliability aspects of the large number of transponders employed.

  18. Large Area Sputter Coating on Glass

    NASA Astrophysics Data System (ADS)

    Katayama, Yoshihito

    Large glass has been used for commercial buildings, housings and vehicles for many years. Glass size for flat displays is getting larger and larger. The glass for the 8th generation is more than 5 m2 in area. Demand of the large glass is increasing not only in these markets but also in a solar cell market growing drastically. Therefore, large area coating is demanded to plus something else on glass more than ever. Sputtering and pyrolysis are the major coating methods on large glass today. Sputtering process is particularly popular because it can deposit a wide variety of materials in good coating uniformity on the glass. This paper describes typical industrial sputtering system and recent progress in sputtering technology. It also shows typical coated glass products in architectural, automotive and display fields and comments on their functions, film stacks and so on.

  19. Cosmogenic Nuclides Study of Large Iron Meteorites

    NASA Astrophysics Data System (ADS)

    Hutzler, A.; Smith, T.; Rochette, P.; Bourles, D. L.; Leya, I.; Gattacceca, J.

    2014-09-01

    Six large iron meteorites were selected (Saint-Aubin, Mont-Dieu, Caille, Morasko, Agoudal, and Gebel Kamil). We measured stable and radiogenic cosmogenic nuclides, to study pre-atmospheric size, cosmic-ray exposure ages and terrestrial ages.

  20. Large-scale regions of antimatter

    SciTech Connect

    Grobov, A. V. Rubin, S. G.

    2015-07-15

    Amodified mechanism of the formation of large-scale antimatter regions is proposed. Antimatter appears owing to fluctuations of a complex scalar field that carries a baryon charge in the inflation era.

  1. A General Conditional Large Deviation Principle

    NASA Astrophysics Data System (ADS)

    La Cour, Brian R.; Schieve, William C.

    2015-10-01

    Given a sequence of Borel probability measures on a Hausdorff space which satisfy a large deviation principle (LDP), we consider the corresponding sequence of measures formed by conditioning on a set B. If the large deviation rate function I is good and effectively continuous, and the conditioning set has the property that (1) and (2) for all , then the sequence of conditional measures satisfies a LDP with the good, effectively continuous rate function , where if and otherwise.

  2. Adaptive Machining Of Large, Somewhat Flexible Parts

    NASA Technical Reports Server (NTRS)

    Gutow, David; Wagner, Garrett; Gilbert, Jeffrey L.; Deily, David

    1996-01-01

    Adaptive machining is method of machining large, somewhat flexible workpieces to close tolerances. Devised for machining precise weld lands on aft skirts of rocket nozzles, but underlying concept generally applicable to precise machining of any of large variety of workpieces deformed by thermal, gravitational, and/or machining forces. For example, in principle, method used to bore precise hole on unanchored end of long cantilever beam.

  3. Large Format Detector Arrays for Astrophysics

    NASA Technical Reports Server (NTRS)

    Moseley, Harvey

    2006-01-01

    Improvements in detector design and advances in fabrication techniques has resulted in devices which can reach fundamental sensitivity limits in many cases. Many pressing astrophysical questions require large arrays of such sensitive detectors. I will describe the state of far infrared through millimeter detector development at NASA/GSFC, the design and production of large format arrays, and the initial deployment of these powerful new tools.

  4. Zone generator for Large Space Telescope technology

    NASA Technical Reports Server (NTRS)

    Erickson, K. E.

    1974-01-01

    A concept is presented for monitoring the optical adjustment and performance of a Large Space Telescope which consists of a 1.2m diameter turntable with a laser stylus to operate at speeds up to 30 rpm. The focus of the laser stylus is under closed loop control. A technique for scribing zones of suitable depth, width, and uniformity applicable to large telescope mirrors is also reported.

  5. Anatomical repair of large incisional hernias.

    PubMed Central

    Loh, A.; Rajkumar, J. S.; South, L. M.

    1992-01-01

    We present a method of repair for large incisional hernias using lateral relieving incisions of the anterior rectus sheath. This is a modification of the methods previously described by Young (1), Hunter (2) and Maguire and Young (3). There were no recurrences in the 13 patients reviewed. Other methods of repair for large incisional hernias are discussed. Images Figure 2a,b Figure 3a,b Figure 4 Figure 5 PMID:1567126

  6. Slew maneuvers of large flexible spacecrafts

    NASA Technical Reports Server (NTRS)

    Kakad, Y. P.

    1990-01-01

    The dynamics and control of arbitrary slew maneuvers of a large flexible spacecraft are developed. The dynamics of slew maneuvers are nonlinear and include the coupling between the rigid orbiter and the flexible appendage. A decentralized control scheme is used to perform a large-angle slew maneuver about an arbitrary axis in space and to suppress the vibrations of the flexible appendage during and after the maneuver.

  7. Primary propulsion/large space system interactions

    NASA Technical Reports Server (NTRS)

    Dergance, R. H.

    1980-01-01

    Three generic types of structural concepts and nonstructural surface densities were selected and combined to represent potential LSS applications. The design characteristics of various classes of large space systems that are impacted by primary propulsion thrust required to effect orbit transfer were identified. The effects of propulsion system thrust-to-mass ratio, thrust transients, and performance on the mass, area, and orbit transfer characteristics of large space systems were determined.

  8. A case for Large Space Systems Technology

    NASA Technical Reports Server (NTRS)

    Huckins, E. K., III

    1980-01-01

    The NASA Large Space Systems Technology (LSST) program, devoted to the development of Space Shuttle-deployable orbiting structures, is reviewed. The LSST program elements are: antennas, space platforms, assembly equipment and devices, surface sensors and control, control and stabilization, and analysis and design systems. Among the specific prospective applications for this technology base may be counted: multipurpose platforms, materials experimentation facilities, energy satellites, large optical and radio arrays, and communications platforms.

  9. Vaccine Therapy With or Without Cryosurgery in Treating Patients With Residual, Relapsed, or Refractory B-Cell Non-Hodgkin Lymphoma

    ClinicalTrials.gov

    2016-04-19

    Cutaneous B-cell Non-Hodgkin Lymphoma; Extranodal Marginal Zone B-cell Lymphoma of Mucosa-associated Lymphoid Tissue; Nodal Marginal Zone B-cell Lymphoma; Adult Diffuse Mixed Cell Lymphoma; Adult Diffuse Small Cleaved Cell Lymphoma; Adult Grade III Lymphomatoid Granulomatosis; Adult Immunoblastic Large Cell Lymphoma; Adult Lymphoblastic Lymphoma; Grade 1 Follicular Lymphoma; Grade 2 Follicular Lymphoma; Grade 3 Follicular Lymphoma; Mantle Cell Lymphoma; Marginal Zone Lymphoma; Small Lymphocytic Lymphoma; Splenic Marginal Zone Lymphoma; Waldenstrom Macroglobulinemia With Nodal Disease

  10. Workflow management in large distributed systems

    NASA Astrophysics Data System (ADS)

    Legrand, I.; Newman, H.; Voicu, R.; Dobre, C.; Grigoras, C.

    2011-12-01

    The MonALISA (Monitoring Agents using a Large Integrated Services Architecture) framework provides a distributed service system capable of controlling and optimizing large-scale, data-intensive applications. An essential part of managing large-scale, distributed data-processing facilities is a monitoring system for computing facilities, storage, networks, and the very large number of applications running on these systems in near realtime. All this monitoring information gathered for all the subsystems is essential for developing the required higher-level services—the components that provide decision support and some degree of automated decisions—and for maintaining and optimizing workflow in large-scale distributed systems. These management and global optimization functions are performed by higher-level agent-based services. We present several applications of MonALISA's higher-level services including optimized dynamic routing, control, data-transfer scheduling, distributed job scheduling, dynamic allocation of storage resource to running jobs and automated management of remote services among a large set of grid facilities.

  11. Large Payload Ground Transportation and Test Considerations

    NASA Technical Reports Server (NTRS)

    Rucker, Michelle A.

    2016-01-01

    Many spacecraft concepts under consideration by the National Aeronautics and Space Administration’s (NASA’s) Evolvable Mars Campaign take advantage of a Space Launch System payload shroud that may be 8 to 10 meters in diameter. Large payloads can theoretically save cost by reducing the number of launches needed--but only if it is possible to build, test, and transport a large payload to the launch site in the first place. Analysis performed previously for the Altair project identified several transportation and test issues with an 8.973 meters diameter payload. Although the entire Constellation Program—including Altair—has since been canceled, these issues serve as important lessons learned for spacecraft designers and program managers considering large payloads for future programs. A transportation feasibility study found that, even broken up into an Ascent and Descent Module, the Altair spacecraft would not fit inside available aircraft. Ground transportation of such large payloads over extended distances is not generally permitted, so overland transportation alone would not be an option. Limited ground transportation to the nearest waterway may be possible, but water transportation could take as long as 67 days per production unit, depending on point of origin and acceptance test facility; transportation from the western United States would require transit through the Panama Canal to access the Kennedy Space Center launch site. Large payloads also pose acceptance test and ground processing challenges. Although propulsion, mechanical vibration, and reverberant acoustic test facilities at NASA’s Plum Brook Station have been designed to accommodate large spacecraft, special handling and test work-arounds may be necessary, which could increase cost, schedule, and technical risk. Once at the launch site, there are no facilities currently capable of accommodating the combination of large payload size and hazardous processing such as hypergolic fuels

  12. Megascours: the morphodynamics of large river confluences

    NASA Astrophysics Data System (ADS)

    Dixon, Simon; Sambrook Smith, Greg; Nicholas, Andrew; Best, Jim; Bull, Jon; Vardy, Mark; Goodbred, Steve; Haque Sarker, Maminul

    2015-04-01

    River confluences are wildly acknowledged as crucial controlling influences upon upstream and downstream morphology and thus landscape evolution. Despite their importance very little is known about their evolution and morphodynamics, and there is a consensus in the literature that confluences represent fixed, nodal points in the fluvial network. Confluences have been shown to generate substantial bed scours around five times greater than mean depth. Previous research on the Ganges-Jamuna junction has shown large river confluences can be highly mobile, potentially 'combing' bed scours across a large area, although the extent to which this is representative of large confluences in general is unknown. Understanding the migration of confluences and associated scours is important for multiple applications including: designing civil engineering infrastructure (e.g. bridges, laying cable, pipelines, etc.), sequence stratigraphic interpretation for reconstruction of past environmental and sea level change, and in the hydrocarbon industry where it is crucial to discriminate autocyclic confluence scours from widespread allocyclic surfaces. Here we present a wide-ranging global review of large river confluence planforms based on analysis of Landsat imagery from 1972 through to 2014. This demonstrates there is an array of confluence morphodynamic types: from freely migrating confluences such as the Ganges-Jamuna, through confluences migrating on decadal timescales and fixed confluences. Along with data from recent geophysical field studies in the Ganges-Brahmaputra-Meghna basin we propose a conceptual model of large river confluence types and hypothesise how these influence morphodynamics and preservation of 'megascours' in the rock record. This conceptual model has implications for sequence stratigraphic models and the correct identification of surfaces related to past sea level change. We quantify the abundance of mobile confluence types by classifying all large confluences

  13. Large Payload Transportation and Test Considerations

    NASA Technical Reports Server (NTRS)

    Rucker, Michelle A.; Pope, James C.

    2011-01-01

    Ironically, the limiting factor to a national heavy lift strategy may not be the rocket technology needed to throw a heavy payload, but rather the terrestrial infrastructure - roads, bridges, airframes, and buildings - necessary to transport, acceptance test, and process large spacecraft. Failure to carefully consider how large spacecraft are designed, and where they are manufactured, tested, or launched, could result in unforeseen cost to modify/develop infrastructure, or incur additional risk due to increased handling or elimination of key verifications. During test and verification planning for the Altair project, a number of transportation and test issues related to the large payload diameter were identified. Although the entire Constellation Program - including Altair - was canceled in the 2011 NASA budget, issues identified by the Altair project serve as important lessons learned for future payloads that may be developed to support national "heavy lift" strategies. A feasibility study performed by the Constellation Ground Operations (CxGO) project found that neither the Altair Ascent nor Descent Stage would fit inside available transportation aircraft. Ground transportation of a payload this large over extended distances is generally not permitted by most states, so overland transportation alone would not have been an option. Limited ground transportation to the nearest waterway may be permitted, but water transportation could take as long as 66 days per production unit, depending on point of origin and acceptance test facility; transportation from the western United States would require transit through the Panama Canal to access the Kennedy Space Center launch site. Large payloads also pose acceptance test and ground processing challenges. Although propulsion, mechanical vibration, and reverberant acoustic test facilities at NASA s Plum Brook Station have been designed to accommodate large spacecraft, special handling and test work-arounds may be necessary

  14. Lenalidomide and Combination Chemotherapy (DA-EPOCH-R) in Treating Patients With MYC-Associated B-Cell Lymphomas

    ClinicalTrials.gov

    2016-08-24

    Adult Grade III Lymphomatoid Granulomatosis; B-cell Chronic Lymphocytic Leukemia; Contiguous Stage II Adult Diffuse Large Cell Lymphoma; Contiguous Stage II Adult Diffuse Mixed Cell Lymphoma; Contiguous Stage II Adult Diffuse Small Cleaved Cell Lymphoma; Contiguous Stage II Adult Immunoblastic Large Cell Lymphoma; Contiguous Stage II Grade 1 Follicular Lymphoma; Contiguous Stage II Grade 2 Follicular Lymphoma; Contiguous Stage II Grade 3 Follicular Lymphoma; Contiguous Stage II Mantle Cell Lymphoma; Contiguous Stage II Marginal Zone Lymphoma; Contiguous Stage II Small Lymphocytic Lymphoma; Cutaneous B-cell Non-Hodgkin Lymphoma; Extranodal Marginal Zone B-cell Lymphoma of Mucosa-associated Lymphoid Tissue; Intraocular Lymphoma; Nodal Marginal Zone B-cell Lymphoma; Noncontiguous Stage II Adult Diffuse Large Cell Lymphoma; Noncontiguous Stage II Adult Diffuse Mixed Cell Lymphoma; Noncontiguous Stage II Adult Diffuse Small Cleaved Cell Lymphoma; Noncontiguous Stage II Adult Immunoblastic Large Cell Lymphoma; Noncontiguous Stage II Grade 1 Follicular Lymphoma; Noncontiguous Stage II Grade 2 Follicular Lymphoma; Noncontiguous Stage II Grade 3 Follicular Lymphoma; Noncontiguous Stage II Mantle Cell Lymphoma; Noncontiguous Stage II Marginal Zone Lymphoma; Noncontiguous Stage II Small Lymphocytic Lymphoma; Progressive Hairy Cell Leukemia, Initial Treatment; Small Intestine Lymphoma; Splenic Marginal Zone Lymphoma; Stage 0 Chronic Lymphocytic Leukemia; Stage I Adult Diffuse Large Cell Lymphoma; Stage I Adult Diffuse Mixed Cell Lymphoma; Stage I Adult Diffuse Small Cleaved Cell Lymphoma; Stage I Adult Hodgkin Lymphoma; Stage I Adult Immunoblastic Large Cell Lymphoma; Stage I Chronic Lymphocytic Leukemia; Stage I Grade 1 Follicular Lymphoma; Stage I Grade 2 Follicular Lymphoma; Stage I Grade 3 Follicular Lymphoma; Stage I Mantle Cell Lymphoma; Stage I Marginal Zone Lymphoma; Stage I Small Lymphocytic Lymphoma; Stage II Adult Hodgkin Lymphoma; Stage II Chronic Lymphocytic

  15. Metrology of Large Parts. Chapter 5

    NASA Technical Reports Server (NTRS)

    Stahl, H. Philip

    2012-01-01

    As discussed in the first chapter of this book, there are many different methods to measure a part using optical technology. Chapter 2 discussed the use of machine vision to measure macroscopic features such as length and position, which was extended to the use of interferometry as a linear measurement tool in chapter 3, and laser or other trackers to find the relation of key points on large parts in chapter 4. This chapter looks at measuring large parts to optical tolerances in the sub-micron range using interferometry, ranging, and optical tools discussed in the previous chapters. The purpose of this chapter is not to discuss specific metrology tools (such as interferometers or gauges), but to describe a systems engineering approach to testing large parts. Issues such as material warpage and temperature drifts that may be insignificant when measuring a part to micron levels under a microscope, as will be discussed in later chapters, can prove to be very important when making the same measurement over a larger part. In this chapter, we will define a set of guiding principles for successfully overcoming these challenges and illustrate the application of these principles with real world examples. While these examples are drawn from specific large optical testing applications, they inform the problems associated with testing any large part to optical tolerances. Manufacturing today relies on micrometer level part performance. Fields such as energy and transportation are demanding higher tolerances to provide increased efficiencies and fuel savings. By looking at how the optics industry approaches sub-micrometer metrology, one can gain a better understanding of the metrology challenges for any larger part specified to micrometer tolerances. Testing large parts, whether optical components or precision structures, to optical tolerances is just like testing small parts, only harder. Identical with what one does for small parts, a metrologist tests large parts and optics

  16. A Pilot Study to Evaluate the Co-Infusion of Ex Vivo Expanded Cord Blood Cells With an Unmanipulated Cord Blood Unit in Patients Undergoing Cord Blood Transplant for Hematologic Malignancies

    ClinicalTrials.gov

    2015-02-10

    Accelerated Phase Chronic Myelogenous Leukemia; Acute Myeloid Leukemia With Multilineage Dysplasia Following Myelodysplastic Syndrome; Adult Acute Lymphoblastic Leukemia in Remission; Adult Acute Myeloid Leukemia in Remission; Adult Acute Myeloid Leukemia With 11q23 (MLL) Abnormalities; Adult Acute Myeloid Leukemia With Del(5q); Adult Acute Myeloid Leukemia With Inv(16)(p13;q22); Adult Acute Myeloid Leukemia With t(15;17)(q22;q12); Adult Acute Myeloid Leukemia With t(16;16)(p13;q22); Adult Acute Myeloid Leukemia With t(8;21)(q22;q22); Adult Nasal Type Extranodal NK/T-cell Lymphoma; Anaplastic Large Cell Lymphoma; Childhood Acute Lymphoblastic Leukemia in Remission; Childhood Acute Myeloid Leukemia in Remission; Childhood Burkitt Lymphoma; Childhood Chronic Myelogenous Leukemia; Childhood Diffuse Large Cell Lymphoma; Childhood Immunoblastic Large Cell Lymphoma; Childhood Myelodysplastic Syndromes; Childhood Nasal Type Extranodal NK/T-cell Lymphoma; Chronic Phase Chronic Myelogenous Leukemia; Contiguous Stage II Adult Burkitt Lymphoma; Contiguous Stage II Adult Diffuse Large Cell Lymphoma; Contiguous Stage II Adult Diffuse Mixed Cell Lymphoma; Contiguous Stage II Adult Immunoblastic Large Cell Lymphoma; Contiguous Stage II Adult Lymphoblastic Lymphoma; Contiguous Stage II Grade 3 Follicular Lymphoma; Contiguous Stage II Mantle Cell Lymphoma; de Novo Myelodysplastic Syndromes; Extranodal Marginal Zone B-cell Lymphoma of Mucosa-associated Lymphoid Tissue; Nodal Marginal Zone B-cell Lymphoma; Noncontiguous Stage II Adult Burkitt Lymphoma; Noncontiguous Stage II Adult Diffuse Large Cell Lymphoma; Noncontiguous Stage II Adult Diffuse Mixed Cell Lymphoma; Noncontiguous Stage II Adult Immunoblastic Large Cell Lymphoma; Noncontiguous Stage II Adult Lymphoblastic Lymphoma; Noncontiguous Stage II Grade 3 Follicular Lymphoma; Noncontiguous Stage II Mantle Cell Lymphoma; Previously Treated Myelodysplastic Syndromes; Prolymphocytic Leukemia; Recurrent Adult Burkitt Lymphoma

  17. Large Fluvial Fans and Exploration for Hydrocarbons

    NASA Technical Reports Server (NTRS)

    Wilkinson, Murray Justin

    2005-01-01

    A report discusses the geological phenomena known, variously, as modern large (or large modern) fluvial fans or large continental fans, from a perspective of exploring for hydrocarbons. These fans are partial cones of river sediment that spread out to radii of 100 km or more. Heretofore, they have not been much recognized in the geological literature probably because they are difficult to see from the ground. They can, however, be seen in photographs taken by astronauts and on other remotely sensed imagery. Among the topics discussed in the report is the need for research to understand what seems to be an association among fluvial fans, alluvial fans, and hydrocarbon deposits. Included in the report is an abstract that summarizes the global distribution of large modern fluvial fans and a proposal to use that distribution as a guide to understanding paleo-fluvial reservoir systems where oil and gas have formed. Also included is an abstract that summarizes what a continuing mapping project has thus far revealed about the characteristics of large fans that have been found in a variety of geological environments.

  18. Development of large aperture composite adaptive optics

    NASA Astrophysics Data System (ADS)

    Kmetik, Viliam; Vitovec, Bohumil; Jiran, Lukas; Nemcova, Sarka; Zicha, Josef; Inneman, Adolf; Mikulickova, Lenka; Pavlica, Richard

    2015-01-01

    Large aperture composite adaptive optics for laser applications is investigated in cooperation of Institute of Plasma Physic, Department of Instrumentation and Control Engineering FME CTU and 5M Ltd. We are exploring opportunity of a large-size high-power-laser deformable-mirror production using a lightweight bimorph actuated structure with a composite core. In order to produce a sufficiently large operational free aperture we are developing new technologies for production of flexible core, bimorph actuator and deformable mirror reflector. Full simulation of a deformable-mirrors structure was prepared and validated by complex testing. A deformable mirror actuation and a response of a complicated structure are investigated for an accurate control of the adaptive optics. An original adaptive optics control system and a bimorph deformable mirror driver were developed. Tests of material samples, components and sub-assemblies were completed. A subscale 120 mm bimorph deformable mirror prototype was designed, fabricated and thoroughly tested. A large-size 300 mm composite-core bimorph deformable mirror was simulated and optimized, fabrication of a prototype is carried on. A measurement and testing facility is modified to accommodate large sizes optics.

  19. Evolution and interaction of large interplanetary streams

    NASA Technical Reports Server (NTRS)

    Whang, Y. C.; Burlaga, L. F.

    1985-01-01

    A computer simulation for the evolution and interaction of large interplanetary streams based on multi-spacecraft observations and an unsteady, one-dimensional MHD model is presented. Two events, each observed by two or more spacecraft separated by a distance of the order of 10 AU, were studied. The first simulation is based on the plasma and magnetic field observations made by two radially-aligned spacecraft. The second simulation is based on an event observed first by Helios-1 in May 1980 near 0.6 AU and later by Voyager-1 in June 1980 at 8.1 AU. These examples show that the dynamical evolution of large-scale solar wind structures is dominated by the shock process, including the formation, collision, and merging of shocks. The interaction of shocks with stream structures also causes a drastic decrease in the amplitude of the solar wind speed variation with increasing heliocentric distance, and as a result of interactions there is a large variation of shock-strengths and shock-speeds. The simulation results shed light on the interpretation for the interaction and evolution of large interplanetary streams. Observations were made along a few limited trajectories, but simulation results can supplement these by providing the detailed evolution process for large-scale solar wind structures in the vast region not directly observed. The use of a quantitative nonlinear simulation model including shock merging process is crucial in the interpretation of data obtained in the outer heliosphere.

  20. IAHS Symposium on Large River Basins

    NASA Astrophysics Data System (ADS)

    Frick, David M.

    The flow regime of large rivers is significantly influenced by man's activities, such as land use or river development. In other cases, there is evidence that climate change is the reason for modified flow regime. When basins are shared by a number of countries, the problems of hydrologic change become even more critical. Therefore, the social and economic consequences of changes in the flow regime of large river basins is far reaching,To improve the understanding of hydrologic processes and to investigate the availability of tools and methods that can be used to analyze the hydrological impacts of changes in flow, the International Association of Hydrologic Sciences (IAHS) and International Commission on Surface Water (ICSW) devoted its symposium, held at the August 1991 XXth General Assembly of the International Union of Geodesy and Geophysics (IUGG) in Vienna, Austria, to the theme “Hydrology for Water Management of Large River Basins.” The theme was divided into the four subtopics of water management and cooperation in large and/or international river basin: flow regimes and water management in relation to changes in climate, river development, and land use; water quality and sediment transport management in a large river environment; and operational flow and water quality forecasting. Both the general problem and organizational and operational aspects were investigated.

  1. Astronomy Outreach for Large and Unique Audiences

    NASA Astrophysics Data System (ADS)

    Lubowich, D.; Sparks, R. T.; Pompea, S. M.; Kendall, J. S.; Dugan, C.

    2013-04-01

    In this session, we discuss different approaches to reaching large audiences. In addition to star parties and astronomy events, the audiences for some of the events include music concerts or festivals, sick children and their families, minority communities, American Indian reservations, and tourist sites such as the National Mall. The goal is to bring science directly to the public—to people who attend astronomy events and to people who do not come to star parties, science museums, or science festivals. These programs allow the entire community to participate in astronomy activities to enhance the public appreciation of science. These programs attract large enthusiastic crowds often with young children participating in these family learning experiences. The public will become more informed, educated, and inspired about astronomy and will also be provided with information that will allow them to continue to learn after this outreach activity. Large and unique audiences often have common problems, and their solutions and the lessons learned will be presented. Interaction with the participants in this session will provide important community feedback used to improve astronomy outreach for large and unique audiences. New ways to expand astronomy outreach to new large audiences will be discussed.

  2. Hot seeding using large Y-123 seeds

    NASA Astrophysics Data System (ADS)

    Scruggs, S. J.; Putman, P. T.; Zhou, Y. X.; Fang, H.; Salama, K.

    2006-07-01

    There are several motivations for increasing the diameter of melt textured single domain discs. The maximum magnetic field produced by a trapped field magnet is proportional to the radius of the sample. Furthermore, the availability of trapped field magnets with large diameter could enable their use in applications that have traditionally been considered to require wound electromagnets, such as beam bending magnets for particle accelerators and electric propulsion. We have investigated the possibility of using large area epitaxial growth instead of the conventional point nucleation growth mechanism. This process involves the use of large Y123 seeds for the purpose of increasing the maximum achievable Y123 single domain size. The hot seeding technique using large Y-123 seeds was employed to seed Y-123 samples. Trapped field measurements indicate that single domain samples were indeed grown by this technique. Microstructural evaluation indicates that growth can be characterized by a rapid nucleation followed by the usual peritectic grain growth which occurs when large seeds are used. Critical temperature measurements show that no local Tc suppression occurs in the vicinity of the seed. This work supports the suggestion of using an iterative method for increasing the size of Y-123 single domains that can be grown.

  3. Baryon resonances in large Nc QCD

    NASA Astrophysics Data System (ADS)

    Matagne, N.; Stancu, Fl.

    2015-01-01

    The current status and open challenges of large Nc QCD baryon spectroscopy are reviewed. After introducing the 1 /Nc expansion method, the latest achievements for the ground state properties are revisited. Next the applicability of this method to excited states is presented using two different approaches with their advantages and disadvantages. Selected results for the spectrum and strong and electromagnetic decays are described. Also further developments for the applicability of the method to excited states are presented, based on the qualitative compatibility between the quark excitation picture and the meson-nucleon scattering picture. A quantitative comparison between results obtained from the mass formula of the 1 /Nc expansion method and quark models brings convincing support to quark models and the implications of different large Nc limits are discussed. The SU(6) spin-flavor structure of the large Nc baryon allows a convenient classification of highly excited resonances into SU(3) multiplets and predicts mass ranges for the missing partners.

  4. Control problems in very large accelerators

    SciTech Connect

    Crowley-Milling, M.C.

    1985-04-01

    There is no fundamental difference of kind in the control requirements between a small and a large accelerator since they are built of the same types of components, which individually have the same types of control inputs and outputs. The main difference is one of scale; the large machine has many more components of each type, and the distances involved are much greater. It is the purpose of this paper to look at the special control problems of large accelerators, which the author shall arbitrarily define as those with a length or circumference in excess of 10 km, and point out where special developments, or the adoption of developments from outside the accelerator control field, can be of assistance in minimizing the cost of the control system.

  5. Stimulated Raman scattering in large plasmas

    SciTech Connect

    Phillion, D.W.; Banner, D.L.

    1980-11-06

    Stimulated Raman scattering is of concern to laser fusion since it can create a hot electron environment which can increase the difficulty of achieving high final fuel densities. In earlier experiments with one micron laser light, the energy measured in Raman-scattered light has been insignificant. But these experiments were done with, at most, about 100 joules of laser energy. The Raman instability has a high threshold which also requires a large plasma to be irradiated with a large diameter spot. Only with a long interaction length can the Raman-scattered light wave convectively grow to a large amplitude, and only in recent long pulse, high energy experiments (4000 joules in 2 ns) at the Shiva laser facility have we observed as much as several percent of the laser light to be Raman-scattered. We find that the Raman instability has a much lower intensity threshold for longer laser pulselength and larger laser spot size on a solid target.

  6. Large molecules in diffuse interstellar clouds

    SciTech Connect

    Lepp, S.; Dalgarno, A.; Van Dishoeck, E.F.; Black, J.H.

    1988-06-01

    The effects of the presence of a substantial component of large molecules on the chemistry of diffuse molecular clouds are explored, and detailed models of the zeta Persei and zeta Ophiuchi clouds are constructed. The major consequence is a reduction in the abundances of singly charged atomic species. The long-standing discrepancy between cloud densities inferred from rotational and fine-structure level populations and from the ionization balance can be resolved by postulating a fractional abundance of large molecules of 1 x 10 to the -7th for zeta Persei and 6 x 10 to the -7th for zeta Ophiuchi. If the large molecules are polycyclic aromatic hydrocarbons (PAH) containing about 50 carbon atoms, they contain 1 percent of the carbon in zeta Persei and 7 percent in zeta Ophiuchi. Other consequences of the possible presence of PAH molecules are discussed. 23 references.

  7. Design of large aperture focal plane shutter

    NASA Astrophysics Data System (ADS)

    Hu, Jia-wen; Ma, Wen-li; Huang, Jin-long

    2012-09-01

    To satisfy the requirement of large telescope, a large aperture focal plane shutter with aperture size of φ200mm was researched and designed to realize, which could be started and stopped in a relative short time with precise position, and also the blades could open and close at the same time at any orientation. Timing-belts and stepper motors were adopted as the drive mechanism. Velocity and position of the stepper motors were controlled by the PWM pulse generated by DSP. Exponential curve is applied to control the velocity of the stepper motors to make the shutter start and stop in a short time. The closing/open time of shutter is 0.2s, which meets the performance requirements of large telescope properly.

  8. Some design considerations for large space structures

    NASA Technical Reports Server (NTRS)

    Bush, H. G.; Mikulas, M. M., Jr.; Heard, W. L., Jr.

    1977-01-01

    Physical characteristics of large skeletal frameworks for space applications are investigated by analyzing one concept: the tetrahedral truss, which is idealized as a sandwich plate with isotropic faces. Appropriate analytical relations are presented in terms of the truss column-element properties, which for calculations were taken as slender graphite/epoxy tubes. Column loads, resulting from gravity-gradient control and orbital transfer, are found to be small for the class structure investigated. Fundamental frequencies of large truss structures are shown to be an order of magnitude lower than large earth-based structures. Permissible loads are shown to result in small lateral deflections of the truss due to low strain at Euler buckling of the slender graphite/epoxy truss column elements. Lateral thermal deflections are found to be a fraction of the truss depth using graphite/epoxy columns.

  9. NASA technology for large space antennas

    NASA Technical Reports Server (NTRS)

    Russell, R. A.; Campbell, T. G.; Freeland, R. E.

    1979-01-01

    Technology developed by NASA in conjunction with industry for potential large, deployable space antennas with applications in communication, radio astronomy and earth observation is reviewed. Concepts for deployable antennas that have been developed to the point of detail design are summarized, including the advanced sunflower precision antenna, the radial rib antenna, the maypole (hoop/column) antenna and the parabolic erectable truss antenna. The assessment of state-of-the-art deployable antenna technology is discussed, and the approach taken by the NASA Large Space Systems Technology (LSST) Program to the development of technology for large space antenna systems is outlined. Finally, the further development of the wrap-rib antenna and the maypole (hoop/column) concept, which meet mission model requirements, to satisfy LSST size and frequency requirements is discussed.

  10. Statistical Ensemble of Large Eddy Simulations

    NASA Technical Reports Server (NTRS)

    Carati, Daniele; Rogers, Michael M.; Wray, Alan A.; Mansour, Nagi N. (Technical Monitor)

    2001-01-01

    A statistical ensemble of large eddy simulations (LES) is run simultaneously for the same flow. The information provided by the different large scale velocity fields is used to propose an ensemble averaged version of the dynamic model. This produces local model parameters that only depend on the statistical properties of the flow. An important property of the ensemble averaged dynamic procedure is that it does not require any spatial averaging and can thus be used in fully inhomogeneous flows. Also, the ensemble of LES's provides statistics of the large scale velocity that can be used for building new models for the subgrid-scale stress tensor. The ensemble averaged dynamic procedure has been implemented with various models for three flows: decaying isotropic turbulence, forced isotropic turbulence, and the time developing plane wake. It is found that the results are almost independent of the number of LES's in the statistical ensemble provided that the ensemble contains at least 16 realizations.

  11. Eyeglass. 1. Very large aperture diffractive telescopes.

    PubMed

    Hyde, R A

    1999-07-01

    The Eyeglass is a very large aperture (25-100-m) space telescope consisting of two distinct spacecraft, separated in space by several kilometers. A diffractive lens provides the telescope s large aperture, and a separate, much smaller, space telescope serves as its mobile eyepiece. Use of a transmissive diffractive lens solves two basic problems associated with very large aperture space telescopes; it is inherently launchable (lightweight, packagable, and deployable) it and virtually eliminates the traditional, very tight surface shape tolerances faced by reflecting apertures. The potential drawback to use of a diffractive primary (very narrow spectral bandwidth) is eliminated by corrective optics in the telescope s eyepiece; the Eyeglass can provide diffraction-limited imaging with either single-band (Deltalambda/lambda approximately 0.1), multiband, or continuous spectral coverage. PMID:18323902

  12. Large-scale sparse singular value computations

    NASA Technical Reports Server (NTRS)

    Berry, Michael W.

    1992-01-01

    Four numerical methods for computing the singular value decomposition (SVD) of large sparse matrices on a multiprocessor architecture are presented. Lanczos and subspace iteration-based methods for determining several of the largest singular triplets (singular values and corresponding left and right-singular vectors) for sparse matrices arising from two practical applications: information retrieval and seismic reflection tomography are emphasized. The target architectures for implementations are the CRAY-2S/4-128 and Alliant FX/80. The sparse SVD problem is well motivated by recent information-retrieval techniques in which dominant singular values and their corresponding singular vectors of large sparse term-document matrices are desired, and by nonlinear inverse problems from seismic tomography applications which require approximate pseudo-inverses of large sparse Jacobian matrices.

  13. Large Deformations of a Soft Porous Material

    NASA Astrophysics Data System (ADS)

    MacMinn, Christopher W.; Dufresne, Eric R.; Wettlaufer, John S.

    2016-04-01

    Compressing a porous material will decrease the volume of the pore space, driving fluid out. Similarly, injecting fluid into a porous material can expand the pore space, distorting the solid skeleton. This poromechanical coupling has applications ranging from cell and tissue mechanics to geomechanics and hydrogeology. The classical theory of linear poroelasticity captures this coupling by combining Darcy's law with Terzaghi's effective stress and linear elasticity in a linearized kinematic framework. Linear poroelasticity is a good model for very small deformations, but it becomes increasingly inappropriate for moderate to large deformations, which are common in the context of phenomena such as swelling and damage, and for soft materials such as gels and tissues. The well-known theory of large-deformation poroelasticity combines Darcy's law with Terzaghi's effective stress and nonlinear elasticity in a rigorous kinematic framework. This theory has been used extensively in biomechanics to model large elastic deformations in soft tissues and in geomechanics to model large elastoplastic deformations in soils. Here, we first provide an overview and discussion of this theory with an emphasis on the physics of poromechanical coupling. We present the large-deformation theory in an Eulerian framework to minimize the mathematical complexity, and we show how this nonlinear theory simplifies to linear poroelasticity under the assumption of small strain. We then compare the predictions of linear poroelasticity with those of large-deformation poroelasticity in the context of two uniaxial model problems: fluid outflow driven by an applied mechanical load (the consolidation problem) and compression driven by a steady fluid throughflow. We explore the steady and dynamical errors associated with the linear model in both situations, as well as the impact of introducing a deformation-dependent permeability. We show that the error in linear poroelasticity is due primarily to kinematic

  14. Heterothermy in large mammals: inevitable or implemented?

    PubMed

    Hetem, Robyn S; Maloney, Shane K; Fuller, Andrea; Mitchell, Duncan

    2016-02-01

    Advances in biologging techniques over the past 20 years have allowed for the remote and continuous measurement of body temperatures in free-living mammals. While there is an abundance of literature on heterothermy in small mammals, fewer studies have investigated the daily variability of body core temperature in larger mammals. Here we review measures of heterothermy and the factors that influence heterothermy in large mammals in their natural habitats, focussing on large mammalian herbivores. The mean 24 h body core temperatures for 17 species of large mammalian herbivores (>10 kg) decreased by ∼1.3°C for each 10-fold increase in body mass, a relationship that remained significant following phylogenetic correction. The degree of heterothermy, as measured by the 24 h amplitude of body core temperature rhythm, was independent of body mass and appeared to be driven primarily by energy and water limitations. When faced with the competing demands of osmoregulation, energy acquisition and water or energy use for thermoregulation, large mammalian herbivores appear to relax the precision of thermoregulation thereby conserving body water and energy. Such relaxation may entail a cost in that an animal moves closer to its thermal limits for performance. Maintaining homeostasis requires trade-offs between regulated systems, and homeothermy apparently is not accorded the highest priority; large mammals are able to maintain optimal homeothermy only if they are well nourished, hydrated, and not compromised energetically. We propose that the amplitude of the 24 h rhythm of body core temperature provides a useful index of any compromise experienced by a free-living large mammal and may predict the performance and fitness of an animal. PMID:25522232

  15. Large space structures - Fantasies and facts

    NASA Technical Reports Server (NTRS)

    Card, M. F.; Boyer, W. J.

    1980-01-01

    A review of large space structures activities from 1973 to 1979 is presented. Long-range studies of space colonies, gigantic solar power stations and projected earth applications revived interest in space activities. Studies suggest opportunities for advanced antenna and platform applications. Matching low-thrust propulsion to large flexible vehicles will be a key technology. Current structures technology investigations include deployable and erectable structures and assembly techniques. Based on orbited structures experience, deployment reliability is a critical issue for deployable structures. For erectable structures, concepts for earth-fabricated and space-fabricated memb

  16. Convergence of large-deviation estimators.

    PubMed

    Rohwer, Christian M; Angeletti, Florian; Touchette, Hugo

    2015-11-01

    We study the convergence of statistical estimators used in the estimation of large-deviation functions describing the fluctuations of equilibrium, nonequilibrium, and manmade stochastic systems. We give conditions for the convergence of these estimators with sample size, based on the boundedness or unboundedness of the quantity sampled, and discuss how statistical errors should be defined in different parts of the convergence region. Our results shed light on previous reports of "phase transitions" in the statistics of free energy estimators and establish a general framework for reliably estimating large-deviation functions from simulation and experimental data and identifying parameter regions where this estimation converges. PMID:26651644

  17. Method of Making Large Area Nanostructures

    NASA Technical Reports Server (NTRS)

    Marks, Alvin M.

    1995-01-01

    A method which enables the high speed formation of nanostructures on large area surfaces is described. The method uses a super sub-micron beam writer (Supersebter). The Supersebter uses a large area multi-electrode (Spindt type emitter source) to produce multiple electron beams simultaneously scanned to form a pattern on a surface in an electron beam writer. A 100,000 x 100,000 array of electron point sources, demagnified in a long electron beam writer to simultaneously produce 10 billion nano-patterns on a 1 meter squared surface by multi-electron beam impact on a 1 cm squared surface of an insulating material is proposed.

  18. Large horizontal axis wind turbine development

    NASA Technical Reports Server (NTRS)

    Robbins, W. H.; Thomas, R. L.

    1979-01-01

    The paper presents an overview of the NASA activities in large horizontal axis wind turbine development. First generation technology large wind turbines (Mod-0A, Mod-1) have been designed and are in operation at selected utility sites. Second generation machines (Mod-2) are scheduled to begin operations on a utility site in 1980. These machines are estimated to generate electricity at less than 4 cents/kWh when manufactured in modest production rates. Meanwhile, plans are being made to continue developing wind turbines which can meet the cost goals of 2 to 3 cents/kWh.

  19. Large-signal klystron simulations using KLSC

    SciTech Connect

    Carlsten, B.E.; Ferguson, P.

    1997-10-01

    The authors describe large-signal klystron simulations using the particle-in-cell code KLSC. This code uses the induced-current model to describe the steady-state cavity modulations and resulting rf fields, and advances the space-charge fields through maxwell`s equations. In this paper, an eight-cavity, high-power S-band klystron simulation is used to highlight various aspects of this simulation technique. In particular, there are specific issues associated with modeling the input cavity, the gain circuit, and the large-signal circuit (including the output cavities), that have to be treated carefully.

  20. The large-scale distribution of galaxies

    NASA Technical Reports Server (NTRS)

    Geller, Margaret J.

    1989-01-01

    The spatial distribution of galaxies in the universe is characterized on the basis of the six completed strips of the Harvard-Smithsonian Center for Astrophysics redshift-survey extension. The design of the survey is briefly reviewed, and the results are presented graphically. Vast low-density voids similar to the void in Bootes are found, almost completely surrounded by thin sheets of galaxies. Also discussed are the implications of the results for the survey sampling problem, the two-point correlation function of the galaxy distribution, the possibility of detecting large-scale coherent flows, theoretical models of large-scale structure, and the identification of groups and clusters of galaxies.

  1. Method and apparatus for extruding large honeycombs

    SciTech Connect

    Kragle, Harry A.; Lambert, David W.; Lipp, G. Daniel

    1996-09-03

    Extrusion die apparatus and an extrusion method for extruding large-cross-section honeycomb structures from plasticized ceramic batch materials are described, the apparatus comprising a die having a support rod connected to its central portion, the support rod being anchored to support means upstream of the die. The support rod and support means act to limit die distortion during extrusion, reducing die strain and stress to levels permitting large honeycomb extrusion without die failure. Dies of optimal thickness are disclosed which reduce the maximum stresses exerted on the die during extrusion.

  2. Electrical system for a large cogeneration plant

    SciTech Connect

    Arvay, G.J. ); Smith, R.T. )

    1992-01-01

    The electrical system, interface, commissioning, and operations requirements of a major multiunit cogeneration plant interconnected with a large utility system through a 230-kV sulfur hexafluoride (SF{sub 6}) gas-insulated substation (GIS) are complex and demanding. This paper describes the electrical requirements, including utility interfaces, engineering, and on-site testing, as applied to the execution of a large, multiunit turnkey cogeneration project in California. The benefits of careful engineering efforts are shown to result in timely and cost effective completion of engineering, manufacturing, installation, testing, and commercial operation.

  3. Production of a large, quiescent, magnetized plasma

    NASA Technical Reports Server (NTRS)

    Landt, D. L.; Ajmera, R. C.

    1976-01-01

    An experimental device is described which produces a large homogeneous quiescent magnetized plasma. In this device, the plasma is created in an evacuated brass cylinder by ionizing collisions between electrons emitted from a large-diameter electron gun and argon atoms in the chamber. Typical experimentally measured values of the electron temperature and density are presented which were obtained with a glass-insulated planar Langmuir probe. It is noted that the present device facilitates the study of phenomena such as waves and diffusion in magnetized plasmas.

  4. Black holes at the Large Hadron Collider.

    PubMed

    Dimopoulos, S; Landsberg, G

    2001-10-15

    If the scale of quantum gravity is near TeV, the CERN Large Hadron Collider will be producing one black hole (BH) about every second. The decays of the BHs into the final states with prompt, hard photons, electrons, or muons provide a clean signature with low background. The correlation between the BH mass and its temperature, deduced from the energy spectrum of the decay products, can test Hawking's evaporation law and determine the number of large new dimensions and the scale of quantum gravity. PMID:11690198

  5. Indian LSSC (Large Space Simulation Chamber) facility

    NASA Technical Reports Server (NTRS)

    Brar, A. S.; Prasadarao, V. S.; Gambhir, R. D.; Chandramouli, M.

    1988-01-01

    The Indian Space Agency has undertaken a major project to acquire in-house capability for thermal and vacuum testing of large satellites. This Large Space Simulation Chamber (LSSC) facility will be located in Bangalore and is to be operational in 1989. The facility is capable of providing 4 meter diameter solar simulation with provision to expand to 4.5 meter diameter at a later date. With such provisions as controlled variations of shroud temperatures and availability of infrared equipment as alternative sources of thermal radiation, this facility will be amongst the finest anywhere. The major design concept and major aspects of the LSSC facility are presented here.

  6. Knowledge Discovery in Large Data Sets

    SciTech Connect

    Simas, Tiago; Silva, Gabriel; Miranda, Bruno; Ribeiro, Rita

    2008-12-05

    In this work we briefly address the problem of unsupervised classification on large datasets, magnitude around 100,000,000 objects. The objects are variable objects, which are around 10% of the 1,000,000,000 astronomical objects that will be collected by GAIA/ESA mission. We tested unsupervised classification algorithms on known datasets such as OGLE and Hipparcos catalogs. Moreover, we are building several templates to represent the main classes of variable objects as well as new classes to build a synthetic dataset of this dimension. In the future we will run the GAIA satellite scanning law on these templates to obtain a testable large dataset.

  7. Structure of large dsDNA viruses

    PubMed Central

    Klose, Thomas; Rossmann, Michael G.

    2015-01-01

    Nucleocytoplasmic large dsDNA viruses (NCLDVs) encompass an ever-increasing group of large eukaryotic viruses, infecting a wide variety of organisms. The set of core genes shared by all these viruses includes a major capsid protein with a double jelly-roll fold forming an icosahedral capsid, which surrounds a double layer membrane that contains the viral genome. Furthermore, some of these viruses, such as the members of the Mimiviridae and Phycodnaviridae have a unique vertex that is used during infection to transport DNA into the host. PMID:25003382

  8. Ground test experiment for large space structures

    NASA Technical Reports Server (NTRS)

    Tollison, D. K.; Waites, H. B.

    1985-01-01

    In recent years a new body of control theory has been developed for the design of control systems for Large Space Structures (LSS). The problems of testing this theory on LSS hardware are aggravated by the expense and risk of actual in orbit tests. Ground tests on large space structures can provide a proving ground for candidate control systems, but such tests require a unique facility for their execution. The current development of such a facility at the NASA Marshall Space Flight Center (MSFC) is the subject of this report.

  9. Design and construction of large capacitor banks

    SciTech Connect

    Whitham, K.; Gritton, D.G.; Holloway, R.W.; Merritt, B.T.

    1983-01-01

    Over the past 12 years, the Laser Program at LLNL has actively pursued laser fusion, using a series of large, solid-state lasers to develop target data leading to reactor designs using the concept of inertial confinement fusion. These lasers are all linear chains of flashlamp driven, Nd-doped glass amplifiers with a master oscillator at the front end. Techniques have been developed during this time to scale the lasers to an arbitrarily large size. A table shows the series of lasers and their parameters that have been developed to date.

  10. Formal Verification of Large Software Systems

    NASA Technical Reports Server (NTRS)

    Yin, Xiang; Knight, John

    2010-01-01

    We introduce a scalable proof structure to facilitate formal verification of large software systems. In our approach, we mechanically synthesize an abstract specification from the software implementation, match its static operational structure to that of the original specification, and organize the proof as the conjunction of a series of lemmas about the specification structure. By setting up a different lemma for each distinct element and proving each lemma independently, we obtain the important benefit that the proof scales easily for large systems. We present details of the approach and an illustration of its application on a challenge problem from the security domain

  11. Deflection of large near-earth objects

    SciTech Connect

    Canavan, G.H.

    1999-01-11

    The Earth is periodically hit by near Earth objects (NEOs) ranging in size from dust to mountains. The small ones are a useful source of information, but those larger than about 1 km can cause global damage. The requirements for the deflection of NEOs with significant material strength are known reasonably well; however, the strength of large NEOs is not known, so those requirements may not apply. Meteor impacts on the Earth`s atmosphere give some information on strength as a function of object size and composition. This information is used here to show that large, weak objects could also be deflected efficiently, if addressed properly.

  12. European Extremely Large Telescope: progress report

    NASA Astrophysics Data System (ADS)

    Tamai, R.; Spyromilio, J.

    2014-07-01

    The European Extremely Large Telescope is a project of the European Southern Observatory to build and operate a 40-m class optical near-infrared telescope. The telescope design effort is largely concluded and construction contracts are being placed with industry and academic/research institutes for the various components. The siting of the telescope in Northern Chile close to the Paranal site allows for an integrated operation of the facility providing significant economies. The progress of the project in various areas is presented in this paper and references to other papers at this SPIE meeting are made.

  13. Large Horizontal-Axis Wind Turbines

    NASA Technical Reports Server (NTRS)

    Thresher, R. W. (Editor)

    1982-01-01

    The proceedings of a workshop held in Cleveland, July 28-30, 1981 are described. The workshop emphasized recent experience in building and testing large propeller-type wind turbines, expanding upon the proceedings of three previous DOE/NASA workshops at which design and analysis topics were considered. A total of 41 papers were presented on the following subjects: current and advanced large wind turbine systems, rotor blade design and manufacture, electric utility activities, research and supporting technology, meteorological characteristics for design and operation, and wind resources assessments for siting.

  14. Large Terrain Modeling and Visualization for Planets

    NASA Technical Reports Server (NTRS)

    Myint, Steven; Jain, Abhinandan; Cameron, Jonathan; Lim, Christopher

    2011-01-01

    Physics-based simulations are actively used in the design, testing, and operations phases of surface and near-surface planetary space missions. One of the challenges in realtime simulations is the ability to handle large multi-resolution terrain data sets within models as well as for visualization. In this paper, we describe special techniques that we have developed for visualization, paging, and data storage for dealing with these large data sets. The visualization technique uses a real-time GPU-based continuous level-of-detail technique that delivers multiple frames a second performance even for planetary scale terrain model sizes.

  15. Tensor methods for large, sparse unconstrained optimization

    SciTech Connect

    Bouaricha, A.

    1996-11-01

    Tensor methods for unconstrained optimization were first introduced by Schnabel and Chow [SIAM J. Optimization, 1 (1991), pp. 293-315], who describe these methods for small to moderate size problems. This paper extends these methods to large, sparse unconstrained optimization problems. This requires an entirely new way of solving the tensor model that makes the methods suitable for solving large, sparse optimization problems efficiently. We present test results for sets of problems where the Hessian at the minimizer is nonsingular and where it is singular. These results show that tensor methods are significantly more efficient and more reliable than standard methods based on Newton`s method.

  16. Large fracture toughness boron-epoxy composites

    NASA Technical Reports Server (NTRS)

    Atkins, A. G.

    1975-01-01

    The high tensile strengths of strong interfacial bonding may be combined with the large fracture toughness of weak interfacial bonding in brittle fiber/brittle matrix composites by intermittently coating the filaments before layup so as to have random alternate weak and strong regions. Appropriate coating materials enable Cook-Gordon Mode I interfacial debonding to take place, which produces very long pull-out lengths with an associated large contribution to toughness. Unidirectional boron-epoxy composites have been so made which have toughnesses greater than 200 kJ/sq m while retaining rule of mixtures tensile strengths. Similar trends have been observed for crossply layups.

  17. Large plasmids of avian Escherichia coli isolates.

    PubMed

    Doetkott, D M; Nolan, L K; Giddings, C W; Berryhill, D L

    1996-01-01

    The plasmid DNA of 30 Escherichia coli isolates from chickens was extracted and examined using techniques designed to isolate large plasmids. This plasmid DNA was examined for the presence of certain known virulence-related genes including cvaC, traT, and some aerobactin-related sequences. Seventeen of the 30 isolates contained from one to four plasmids greater than 50 kb in size. Eleven of these 17 strains possessed plasmids greater than 100 kb in size. Therefore, E. coli isolates of chickens frequently contain large plasmids, and many of these plasmids are likely to contain virulence-related sequences. PMID:8980827

  18. Large eddy simulation in the ocean

    NASA Astrophysics Data System (ADS)

    Scotti, Alberto

    2010-12-01

    Large eddy simulation (LES) is a relative newcomer to oceanography. In this review, both applications of traditional LES to oceanic flows and new oceanic LES still in an early stage of development are discussed. The survey covers LES applied to boundary layer flows, traditionally an area where LES has provided considerable insight into the physics of the flow, as well as more innovative applications, where new SGS closure schemes need to be developed. The merging of LES with large-scale models is also briefly reviewed.

  19. Large volume flow-through scintillating detector

    DOEpatents

    Gritzo, Russ E.; Fowler, Malcolm M.

    1995-01-01

    A large volume flow through radiation detector for use in large air flow situations such as incinerator stacks or building air systems comprises a plurality of flat plates made of a scintillating material arranged parallel to the air flow. Each scintillating plate has a light guide attached which transfers light generated inside the scintillating plate to an associated photomultiplier tube. The output of the photomultiplier tubes are connected to electronics which can record any radiation and provide an alarm if appropriate for the application.

  20. Cytogenetic findings in a large bowel adenocarcinoma.

    PubMed

    Ferti-Passantonopoulou, A; Panani, A; Avgerinos, A; Raptis, S

    1986-04-15

    Cytogenetic analysis of a biopsy specimen taken during sigmoidoscopy from an adenocarcinoma of the large bowel revealed a hypodiploid karyotype with numerical and structural abnormalities identified as trisomy 7, t(3;12), t(1;17), interstitial deletion of the long arm of a chromosome #5 and loss of the Y chromosome with double X chromosomes. The possibility of this karyotype being a further evolutionary step in a subgroup of large bowel cancers and the clinical value of the above findings are discussed. PMID:3456826

  1. Large muon electric dipole moment from flavor?

    SciTech Connect

    Hiller, Gudrun; Huitu, Katri; Rueppell, Timo; Laamanen, Jari

    2010-11-01

    We study the prospects and opportunities of a large muon electric dipole moment (EDM) of the order (10{sup -24}-10{sup -22}) ecm. We investigate how natural such a value is within the general minimal supersymmetric extension of the standard model with CP violation from lepton flavor violation in view of the experimental constraints. In models with hybrid gauge-gravity-mediated supersymmetry breaking, a large muon EDM is indicative for the structure of flavor breaking at the Planck scale, and points towards a high messenger scale.

  2. [Large vessels vasculopathy in systemic sclerosis].

    PubMed

    Tejera Segura, Beatriz; Ferraz-Amaro, Iván

    2015-12-01

    Vasculopathy in systemic sclerosis is a severe, in many cases irreversible, manifestation that can lead to amputation. While the classical clinical manifestations of the disease have to do with the involvement of microcirculation, proximal vessels of upper and lower limbs can also be affected. This involvement of large vessels may be related to systemic sclerosis, vasculitis or atherosclerotic, and the differential diagnosis is not easy. To conduct a proper and early diagnosis, it is essential to start prompt appropriate treatment. In this review, we examine the involvement of large vessels in scleroderma, an understudied manifestation with important prognostic and therapeutic implications. PMID:25726305

  3. Construction and assembly of large space structures

    NASA Technical Reports Server (NTRS)

    Mar, J. W.; Miller, R. H.; Bowden, M. L.

    1980-01-01

    Three aspects of the construction and assembly of large space structures, namely transportation costs, human productivity in space and the source of materials (lunar vs terrestrial), are considered. Studies on human productivity have been so encouraging that the cost of human labor is now regarded as much less important than transportation costs. It is pointed out that these costs, although high, are extremely demand-sensitive. Even with high demand, however, the construction of several large systems would warrant the use of lunar materials and space manufacturing. The importance of further research is stressed in order to establish the optimum tradeoff between automation and manual assembly.

  4. Timing signatures of large scale solar eruptions

    NASA Astrophysics Data System (ADS)

    Balasubramaniam, K. S.; Hock-Mysliwiec, Rachel; Henry, Timothy; Kirk, Michael S.

    2016-05-01

    We examine the timing signatures of large solar eruptions resulting in flares, CMEs and Solar Energetic Particle events. We probe solar active regions from the chromosphere through the corona, using data from space and ground-based observations, including ISOON, SDO, GONG, and GOES. Our studies include a number of flares and CMEs of mostly the M- and X-strengths as categorized by GOES. We find that the chromospheric signatures of these large eruptions occur 5-30 minutes in advance of coronal high temperature signatures. These timing measurements are then used as inputs to models and reconstruct the eruptive nature of these systems, and explore their utility in forecasts.

  5. Large natural geophysical events: planetary planning

    SciTech Connect

    Knox, J.B.; Smith, J.V.

    1984-09-01

    Geological and geophysical data suggest that during the evolution of the earth and its species, that there have been many mass extinctions due to large impacts from comets and large asteroids, and major volcanic events. Today, technology has developed to the stage where we can begin to consider protective measures for the planet. Evidence of the ecological disruption and frequency of these major events is presented. Surveillance and warning systems are most critical to develop wherein sufficient lead times for warnings exist so that appropriate interventions could be designed. The long term research undergirding these warning systems, implementation, and proof testing is rich in opportunities for collaboration for peace.

  6. 75 FR 21455 - Large Trader Reporting System

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-23

    ...; and (3) provide certain additional information in response to a Commission request. The proposed rule... regarding a response provided in Schedule 6 to a large trader's Form 13H concerning the identification of... the Federal eRulemaking Portal ( http://www.regulations.gov ). Follow the instructions for...

  7. 77 FR 18109 - Assessments, Large Bank Pricing

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-27

    ...The FDIC proposes to amend its regulations to revise some of the definitions used to determine assessment rates for large and highly complex insured depository institutions. The FDIC believes these proposed amendments will result in more consistent reporting, better reflect risk to the FDIC, significantly reduce reporting burden, and satisfy many concerns voiced by the banking...

  8. The Large Context Problem (LCP) Approach

    ERIC Educational Resources Information Center

    Stinner, Arthur

    2006-01-01

    This article traces the development of a contextual approach to the teaching of science (physics) subsequently called the Large Context Problem (LCP) approach. This approach is based on the general observation that learning could be well motivated by a context with one unifying central idea capable of capturing the imagination of the students. The…

  9. Large Scale Commodity Clusters for Lattice QCD

    SciTech Connect

    A. Pochinsky; W. Akers; R. Brower; J. Chen; P. Dreher; R. Edwards; S. Gottlieb; D. Holmgren; P. Mackenzie; J. Negele; D. Richards; J. Simone; W. Watson

    2002-06-01

    We describe the construction of large scale clusters for lattice QCD computing being developed under the umbrella of the U.S. DoE SciDAC initiative. We discuss the study of floating point and network performance that drove the design of the cluster, and present our plans for future multi-Terascale facilities.

  10. Large Indoor Sports and Recreation Facilities.

    ERIC Educational Resources Information Center

    Seidler, Todd

    This paper presents an overview and analysis of field houses, stadiums, arenas, and campus recreation centers. All are large indoor sports or recreation facilities. In general, stadiums and arenas are spectator facilities while field houses and campus recreation centers are primarily designed for activity. A college field house is a structure that…

  11. Responses of large mammals to climate change

    PubMed Central

    Hetem, Robyn S; Fuller, Andrea; Maloney, Shane K; Mitchell, Duncan

    2014-01-01

    Most large terrestrial mammals, including the charismatic species so important for ecotourism, do not have the luxury of rapid micro-evolution or sufficient range shifts as strategies for adjusting to climate change. The rate of climate change is too fast for genetic adaptation to occur in mammals with longevities of decades, typical of large mammals, and landscape fragmentation and population by humans too widespread to allow spontaneous range shifts of large mammals, leaving only the expression of latent phenotypic plasticity to counter effects of climate change. The expression of phenotypic plasticity includes anatomical variation within the same species, changes in phenology, and employment of intrinsic physiological and behavioral capacity that can buffer an animal against the effects of climate change. Whether that buffer will be realized is unknown, because little is known about the efficacy of the expression of plasticity, particularly for large mammals. Future research in climate change biology requires measurement of physiological characteristics of many identified free-living individual animals for long periods, probably decades, to allow us to detect whether expression of phenotypic plasticity will be sufficient to cope with climate change.

  12. Tutoring Large Numbers: An Unmet Challenge

    ERIC Educational Resources Information Center

    Lentell, Helen; O'Rourke, Jennifer

    2004-01-01

    Open and distance learning (ODL) is increasingly being regarded as a viable policy option for developing countries with limited educational resources for buildings, books and trained teachers, seeking to increase accessibility for large numbers of learners in education and training opportunities. Advocates of ODL as an appropriate solution to…

  13. Insights into Our Understandings of Large Numbers

    ERIC Educational Resources Information Center

    Kastberg, Signe E.; Walker, Vicki

    2008-01-01

    This article explores prospective teachers' understandings of one million to gain insights into the development of adult understanding of large numbers. Themes in the prospective teachers' work included number associated with a quantity of objects, number as an abstraction, and additive and multiplicative approaches. The authors suggest that the…

  14. Reading the World through Very Large Numbers

    ERIC Educational Resources Information Center

    Greer, Brian; Mukhopadhyay, Swapna

    2010-01-01

    One original, and continuing, source of interest in large numbers is observation of the natural world, such as trying to count the stars on a clear night or contemplation of the number of grains of sand on the seashore. Indeed, a search of the internet quickly reveals many discussions of the relative numbers of stars and grains of sand. Big…

  15. Uniform reflective films deposited on large surfaces

    NASA Technical Reports Server (NTRS)

    1966-01-01

    Specially designed baffle which intercepts varying amounts of the vapor stream from an evaporant source, vacuum deposits films of uniform thickness on large substrates, using a single small area evaporation source. A mirror coated by this method will have a reflectance as high as 82 percent at 1216 angstroms with a variation of only plus/minus 2 percent over the surface.

  16. Decorum in the Large Lecture Class

    ERIC Educational Resources Information Center

    Druger, Marvin

    2008-01-01

    Anyone who has taught a lecture to a large group of students has probably experienced undesirable student behaviors. The author, who has taught an introductory college biology course at Syracuse University for 45 years, relates that an important part of his teaching philosophy is that everyone should learn from everything that they do, and…

  17. Report of the large solenoid detector group

    SciTech Connect

    Hanson, G.G.; Mori, S.; Pondrom, L.G.; Williams, H.H.; Barnett, B.; Barnes, V.; Cashmore, R.; Chiba, M.; DeSalvo, R.; Devlin, T.

    1987-09-01

    This report presents a conceptual design of a large solenoid for studying physics at the SSC. The parameters and nature of the detector have been chosen based on present estimates of what is required to allow the study of heavy quarks, supersymmetry, heavy Higgs particles, WW scattering at large invariant masses, new W and Z bosons, and very large momentum transfer parton-parton scattering. Simply stated, the goal is to obtain optimum detection and identification of electrons, muons, neutrinos, jets, W's and Z's over a large rapidity region. The primary region of interest extends over +-3 units of rapidity, although the calorimetry must extend to +-5.5 units if optimal missing energy resolution is to be obtained. A magnetic field was incorporated because of the importance of identifying the signs of the charges for both electrons and muons and because of the added possibility of identifying tau leptons and secondary vertices. In addition, the existence of a magnetic field may prove useful for studying new physics processes about which we currently have no knowledge. Since hermeticity of the calorimetry is extremely important, the entire central and endcap calorimeters were located inside the solenoid. This does not at the moment seem to produce significant problems (although many issues remain to be resolved) and in fact leads to a very effective muon detector in the central region.

  18. Finite N from resurgent large N

    NASA Astrophysics Data System (ADS)

    Couso-Santamaría, Ricardo; Schiappa, Ricardo; Vaz, Ricardo

    2015-05-01

    Due to instanton effects, gauge-theoretic large N expansions yield asymptotic series, in powers of 1 /N2. The present work shows how to generically make such expansions meaningful via their completion into resurgent transseries, encoding both perturbative and nonperturbative data. Large N resurgent transseries compute gauge-theoretic finite N results nonperturbatively (no matter how small N is). Explicit calculations are carried out within the gauge theory prototypical example of the quartic matrix model. Due to integrability in the matrix model, it is possible to analytically compute (fixed integer) finite N results. At the same time, the large N resurgent transseries for the free energy of this model was recently constructed. Together, it is shown how the resummation of the large N resurgent transseries matches the analytical finite N results up to remarkable numerical accuracy. Due to lack of Borel summability, Stokes phenomena has to be carefully taken into account, implying that instantons play a dominant role in describing the finite N physics. The final resurgence results can be analytically continued, defining gauge theory for any complex value of N.

  19. Large astronomical catalog management for telescope operations

    NASA Astrophysics Data System (ADS)

    Baruffolo, Andrea; Benacchio, Leopoldo

    1998-07-01

    Large astronomical catalogues containing from a million up to hundreds of millions records are currently available, even larger catalogues will be released in the near future. They will have an important operational role since they will be used throughout the observing cycle of next generation large telescopes, for proposal and observation preparation, telescope scheduling, selection of guide stars, etc. These large databases pose new problems for fast and general access. Solutions based on custom software or on customized versions of specific catalogues have been proposed, but the problem will benefit from a more general database approach. While traditional database technologies have proven to be inadequate for this task, new technologies are emerging, in particular that of Object Relational DBMSs, that seem to be suitable to solve the problem. In this paper we describe our experiences in experimenting with ORDBMSs for the management of large astronomical catalogues. We worked especially on the database query language and access methods. In the first field to extend the database query language capabilities with astronomical functionalities and to support typical astronomical queries.In the second, to speed up the execution of queries containing astronomical predicates.

  20. Large area space solar cell assemblies

    NASA Technical Reports Server (NTRS)

    Spitzer, M. B.; Nowlan, M. J.

    1982-01-01

    Development of a large area space solar cell assembly is presented. The assembly consists of an ion implanted silicon cell and glass cover. The important attributes of fabrication are (1) use of a back surface field which is compatible with a back surface reflector, and (2) integration of coverglass application and call fabrication.

  1. Improving Interactions in the Large Language Class.

    ERIC Educational Resources Information Center

    Raymond, Patricia M.; Raymond, Jacques; Pilon, Daniel

    1998-01-01

    Describes a prototypical microcomputer system that improves the interactions between teacher and large language classes in a traditional language classroom setting. This system achieves dynamic interactions through multiple student/professor interventions, immediate and delayed feedback, and individual teacher/student conferences. The system uses…

  2. Large Deviations: Advanced Probability for Undergrads

    ERIC Educational Resources Information Center

    Rolls, David A.

    2007-01-01

    In the branch of probability called "large deviations," rates of convergence (e.g. of the sample mean) are considered. The theory makes use of the moment generating function. So, particularly for sums of independent and identically distributed random variables, the theory can be made accessible to senior undergraduates after a first course in…

  3. The Large Crater Origin of SNC Meteorites.

    PubMed

    Vickery, A M; Melosh, H J

    1987-08-14

    A large body of evidence strongly suggests that the shergottite, nakhlite, and Chassigny (SNC) meteorites are from Mars. Various mechanisms for the ejection of large rocks at martian escape velocity (5 kilometers per second) have been investigated, but none has proved wholly satisfactory. This article examines a number of possible ejection and cosmic-ray exposure histories to determine which is most plausible. For each possible history, the Melosh spallation model is used to estimate the size of the crater required to produce ejecta fragments of the required size with velocities >/=5 kilometers per second and to produce a total mass of solid ejecta consistent with the observed mass flux of SNC meteorites. Estimates of crater production rates on Mars are then used to evaluate the probability that sufficiently large craters have formed during the available time. The results indicate that the SNC meteorites were probably ejected from a very large crater (> 100 kilometers in diameter) about 200 million years ago, and that cosmic-ray exposure of the recovered meteorites was initiated after collisional fragmentation of the original ejecta in space at much later times (0.5 to 10 million years ago). PMID:17751563

  4. Microwave performance characterization of large space antennas

    NASA Technical Reports Server (NTRS)

    Bathker, D. A. (Editor)

    1977-01-01

    Performance capabilities of large microwave space antenna configurations with apertures generally from 100 wavelengths upwards are discussed. Types of antennas considered include: phased arrays, lenses, reflectors, and hybrid combinations of phased arrays with reflectors or lenses. The performance characteristics of these broad classes of antennas are examined and compared in terms of applications.

  5. Densifying forest biomass into large round bales

    SciTech Connect

    Fridley, J.L.; Burkhardt, T.H.

    1984-01-01

    A large round-bale hay baler was modified to handle forest biomass. Material baled, feed orientation, and baler belt tension were varied to observe their effects on the baling process and bale density. Torque and power required to drive the baler were measured. 12 references.

  6. The repetition of large-earthquake ruptures.

    PubMed Central

    Sieh, K

    1996-01-01

    This survey of well-documented repeated fault rupture confirms that some faults have exhibited a "characteristic" behavior during repeated large earthquakes--that is, the magnitude, distribution, and style of slip on the fault has repeated during two or more consecutive events. In two cases faults exhibit slip functions that vary little from earthquake to earthquake. In one other well-documented case, however, fault lengths contrast markedly for two consecutive ruptures, but the amount of offset at individual sites was similar. Adjacent individual patches, 10 km or more in length, failed singly during one event and in tandem during the other. More complex cases of repetition may also represent the failure of several distinct patches. The faults of the 1992 Landers earthquake provide an instructive example of such complexity. Together, these examples suggest that large earthquakes commonly result from the failure of one or more patches, each characterized by a slip function that is roughly invariant through consecutive earthquake cycles. The persistence of these slip-patches through two or more large earthquakes indicates that some quasi-invariant physical property controls the pattern and magnitude of slip. These data seem incompatible with theoretical models that produce slip distributions that are highly variable in consecutive large events. Images Fig. 3 Fig. 7 Fig. 9 PMID:11607662

  7. Management of large-scale technology

    NASA Technical Reports Server (NTRS)

    Levine, A.

    1985-01-01

    Two major themes are addressed in this assessment of the management of large-scale NASA programs: (1) how a high technology agency was a decade marked by a rapid expansion of funds and manpower in the first half and almost as rapid contraction in the second; and (2) how NASA combined central planning and control with decentralized project execution.

  8. Large-Scale Organizational Performance Improvement.

    ERIC Educational Resources Information Center

    Pilotto, Rudy; Young, Jonathan O'Donnell

    1999-01-01

    Describes the steps involved in a performance improvement program in the context of a large multinational corporation. Highlights include a training program for managers that explained performance improvement; performance matrices; divisionwide implementation, including strategic planning; organizationwide training of all personnel; and the…

  9. A Large Scale Computer Terminal Output Controller.

    ERIC Educational Resources Information Center

    Tucker, Paul Thomas

    This paper describes the design and implementation of a large scale computer terminal output controller which supervises the transfer of information from a Control Data 6400 Computer to a PLATO IV data network. It discusses the cost considerations leading to the selection of educational television channels rather than telephone lines for…

  10. The Large Area Crop Inventory Experiment (LACIE)

    NASA Technical Reports Server (NTRS)

    Macdonald, R. B.

    1976-01-01

    A Large Area Crop Inventory Experiment (LACIE) was undertaken to prove out an economically important application of remote sensing from space. The experiment focused upon determination of wheat acreages in the U.S. Great Plains and upon the development and testing of yield models. The results and conclusions are presented.

  11. Mass extinctions caused by large bolide impacts

    SciTech Connect

    Alvarez, L.W.

    1987-07-01

    Evidence indicates that the collision of Earth and a large piece of Solar System derbris such as a meteoroid, asteroid or comet caused the great extinctions of 65 million years ago, leading to the transition from the age of the dinosaurs to the age of the mammals.

  12. Employment of the Disabled in Large Corporations.

    ERIC Educational Resources Information Center

    Rabby, Rami

    1983-01-01

    Large corporations are in a unique position to employ the disabled, but they sometimes lack the motivation to do so. The author discusses elements of a corporate policy for the disabled, ways of formulating and disseminating it, assignment of responsibility, changes in management attitudes, and the special case of the multinational company.…

  13. Large size space construction for space exploitation

    NASA Astrophysics Data System (ADS)

    Kondyurin, Alexey

    2016-07-01

    Space exploitation is impossible without large space structures. We need to make sufficient large volume of pressurized protecting frames for crew, passengers, space processing equipment, & etc. We have to be unlimited in space. Now the size and mass of space constructions are limited by possibility of a launch vehicle. It limits our future in exploitation of space by humans and in development of space industry. Large-size space construction can be made with using of the curing technology of the fibers-filled composites and a reactionable matrix applied directly in free space. For curing the fabric impregnated with a liquid matrix (prepreg) is prepared in terrestrial conditions and shipped in a container to orbit. In due time the prepreg is unfolded by inflating. After polymerization reaction, the durable construction can be fitted out with air, apparatus and life support systems. Our experimental studies of the curing processes in the simulated free space environment showed that the curing of composite in free space is possible. The large-size space construction can be developed. A project of space station, Moon base, Mars base, mining station, interplanet space ship, telecommunication station, space observatory, space factory, antenna dish, radiation shield, solar sail is proposed and overviewed. The study was supported by Humboldt Foundation, ESA (contract 17083/03/NL/SFe), NASA program of the stratospheric balloons and RFBR grants (05-08-18277, 12-08-00970 and 14-08-96011).

  14. Technology for large tandem mirror experiments

    SciTech Connect

    Thomassen, K.I.

    1980-09-04

    Construction of a large tandem mirror (MFTF-B) will soon begin at Lawrence Livermore National Laboratory (LLNL). Designed to reach break-even plasma conditions, the facility will significantly advance the physics and technology of magnetic-mirror-based fusion reactors. This paper describes the objectives and the design of the facility.

  15. Large communications platforms versus smaller satellites

    NASA Technical Reports Server (NTRS)

    1979-01-01

    Communications systems using large platforms are compared with systems using conventional satellites. Systems models were generated and compared for U.S. domestic application and for 1 INTELSAT's international and domestic transponder lease application. Technology advances were assumed the platforms and the evolution of conventional satellites.

  16. Collaboration within Large Groups in the Classroom

    ERIC Educational Resources Information Center

    Szewkis, Eyal; Nussbaum, Miguel; Rosen, Tal; Abalos, Jose; Denardin, Fernanda; Caballero, Daniela; Tagle, Arturo; Alcoholado, Cristian

    2011-01-01

    The purpose of this paper is to show how a large group of students can work collaboratively in a synchronous way within the classroom using the cheapest possible technological support. Making use of the features of Single Display Groupware and of Multiple Mice we propose a computer-supported collaborative learning approach for big groups within…

  17. Kids and Chemistry: Large Event Guide.

    ERIC Educational Resources Information Center

    Tinnesand, Michael

    This guide is intended to provide Kids and Chemistry (K&C) with a variety of age-appropriate, fun, and safe demonstrations. It features information on planning a large event and includes safety guidelines. Several activities are included under each major topic. Topics include: (1) Acids and Bases; (2) Unsigned; (3) Kool Tie-Dye; (4) Secret…

  18. Modal Vibration Analysis of Large Castings

    NASA Technical Reports Server (NTRS)

    Werlink, Rudolph J.; Margasahayam, Ravi N.

    2009-01-01

    The art of experimental modal vibration analysis (MVA) has been extended to apply to large castings. This extension was made to enable the use of experimental MVA as a relatively inexpensive, simple means of assessing the internal structural integrity of tread shoes of crawler transporters used to move spacecraft to the launch pad at Kennedy Space Center. Each tread shoe is made from cast iron and weighs about a ton (has a mass .907 kg). The present extended version of experimental MVA could also be applied to other large castings. It could be especially useful to manufacturers as a means of rapidly discriminating against large castings that contain unacceptably large concentrations of internal defects. The use of experimental MVA to assess structural integrity is not new. What are new here are those aspects of the extension of experimental MVA that pertain to the application of MVA to objects so massive that it may not be practical or cost effective to mount them in special test fixtures that impose special test boundary conditions to test them in place under normal conditions of use.

  19. Large-Eddy Simulation and Multigrid Methods

    SciTech Connect

    Falgout,R D; Naegle,S; Wittum,G

    2001-06-18

    A method to simulate turbulent flows with Large-Eddy Simulation on unstructured grids is presented. Two kinds of dynamic models are used to model the unresolved scales of motion and are compared with each other on different grids. Thereby the behavior of the models is shown and additionally the feature of adaptive grid refinement is investigated. Furthermore the parallelization aspect is addressed.

  20. Design evolution of large wind turbine generators

    NASA Technical Reports Server (NTRS)

    Spera, D. A.

    1979-01-01

    During the past five years, the goals of economy and reliability have led to a significant evolution in the basic design--both external and internal--of large wind turbine systems. To show the scope and nature of recent changes in wind turbine designs, development of three types are described: (1) system configuration developments; (2) computer code developments; and (3) blade technology developments.

  1. Pronunciation Modeling for Large Vocabulary Speech Recognition

    ERIC Educational Resources Information Center

    Kantor, Arthur

    2010-01-01

    The large pronunciation variability of words in conversational speech is one of the major causes of low accuracy in automatic speech recognition (ASR). Many pronunciation modeling approaches have been developed to address this problem. Some explicitly manipulate the pronunciation dictionary as well as the set of the units used to define the…

  2. Computerized Torque Control for Large dc Motors

    NASA Technical Reports Server (NTRS)

    Willett, Richard M.; Carroll, Michael J.; Geiger, Ronald V.

    1987-01-01

    Speed and torque ranges in generator mode extended. System of shunt resistors, electronic switches, and pulse-width modulation controls torque exerted by large, three-phase, electronically commutated dc motor. Particularly useful for motor operating in generator mode because it extends operating range to low torque and high speed.

  3. Large-scale CFB combustion demonstration project

    SciTech Connect

    Nielsen, P.T.; Hebb, J.L.; Aquino, R.

    1998-07-01

    The Jacksonville Electric Authority's large-scale CFB demonstration project is described. Given the early stage of project development, the paper focuses on the project organizational structure, its role within the Department of Energy's Clean Coal Technology Demonstration Program, and the projected environmental performance. A description of the CFB combustion process in included.

  4. Large-scale CFB combustion demonstration project

    SciTech Connect

    Nielsen, P.T.; Hebb, J.L.; Aquino, R.

    1998-04-01

    The Jacksonville Electric Authority`s large-scale CFB demonstration project is described. Given the early stage of project development, the paper focuses on the project organizational structure, its role within the Department of Energy`s Clean Coal Technology Demonstration Program, and the projected environmental performance. A description of the CFB combustion process is included.

  5. Small and large number discrimination in guppies.

    PubMed

    Piffer, Laura; Agrillo, Christian; Hyde, Daniel C

    2012-03-01

    Non-verbal numerical behavior in human infants, human adults, and non-human primates appears to be rooted in two distinct mechanisms: a precise system for tracking and comparing small numbers of items simultaneously (up to 3 or 4 items) and an approximate system for estimating numerical magnitude of a group of objects. The most striking evidence that these two mechanisms are distinct comes from the apparent inability of young human infants and non-human primates to compare quantites across the small (<3 or 4)/large (>4) number boundary. We ask whether this distinction is present in lower animal species more distantly related to humans, guppies (Poecilia reticulata). We found that, like human infants and non-human primates, fish succeed at comparisons between large numbers only (5 vs. 10), succeed at comparisons between small numbers only (3 vs. 4), but systematically fail at comparisons that closely span the small/large boundary (3 vs. 5). Furthermore, increasing the distance between the small and large number resulted in successful discriminations (3 vs. 6, 3 vs. 7, and 3 vs. 9). This pattern of successes and failures is similar to those observed in human infants and non-human primates to suggest that the two systems are present and functionally distinct across a wide variety of animal species. PMID:21909934

  6. Modeling needs for very large systems.

    SciTech Connect

    Stein, Joshua S.

    2010-10-01

    Most system performance models assume a point measurement for irradiance and that, except for the impact of shading from nearby obstacles, incident irradiance is uniform across the array. Module temperature is also assumed to be uniform across the array. For small arrays and hourly-averaged simulations, this may be a reasonable assumption. Stein is conducting research to characterize variability in large systems and to develop models that can better accommodate large system factors. In large, multi-MW arrays, passing clouds may block sunlight from a portion of the array but never affect another portion. Figure 22 shows that two irradiance measurements at opposite ends of a multi-MW PV plant appear to have similar irradiance (left), but in fact the irradiance is not always the same (right). Module temperature may also vary across the array, with modules on the edges being cooler because they have greater wind exposure. Large arrays will also have long wire runs and will be subject to associated losses. Soiling patterns may also vary, with modules closer to the source of soiling, such as an agricultural field, receiving more dust load. One of the primary concerns associated with this effort is how to work with integrators to gain access to better and more comprehensive data for model development and validation.

  7. Understanding Student Performance in a Large Class

    ERIC Educational Resources Information Center

    Snowball, Jen D.; Boughey, Chrissie

    2012-01-01

    Across the world, university teachers are increasingly being required to engage with diversity in the classes they teach. Using the data from a large Economics 1 class at a South African university, this attempts to understand the effects of diversity on chances of success and how assessment can impact on this. By demonstrating how theory can be…

  8. Unification and large-scale structure.

    PubMed Central

    Laing, R A

    1995-01-01

    The hypothesis of relativistic flow on parsec scales, coupled with the symmetrical (and therefore subrelativistic) outer structure of extended radio sources, requires that jets decelerate on scales observable with the Very Large Array. The consequences of this idea for the appearances of FRI and FRII radio sources are explored. PMID:11607609

  9. Responses of large mammals to climate change.

    PubMed

    Hetem, Robyn S; Fuller, Andrea; Maloney, Shane K; Mitchell, Duncan

    2014-01-01

    Most large terrestrial mammals, including the charismatic species so important for ecotourism, do not have the luxury of rapid micro-evolution or sufficient range shifts as strategies for adjusting to climate change. The rate of climate change is too fast for genetic adaptation to occur in mammals with longevities of decades, typical of large mammals, and landscape fragmentation and population by humans too widespread to allow spontaneous range shifts of large mammals, leaving only the expression of latent phenotypic plasticity to counter effects of climate change. The expression of phenotypic plasticity includes anatomical variation within the same species, changes in phenology, and employment of intrinsic physiological and behavioral capacity that can buffer an animal against the effects of climate change. Whether that buffer will be realized is unknown, because little is known about the efficacy of the expression of plasticity, particularly for large mammals. Future research in climate change biology requires measurement of physiological characteristics of many identified free-living individual animals for long periods, probably decades, to allow us to detect whether expression of phenotypic plasticity will be sufficient to cope with climate change. PMID:27583293

  10. Sterilization for Large Volunteer Temporary Clinics.

    PubMed

    Cuny, Eve

    2015-12-01

    Large portable clinics staffed by volunteers present many unique challenges, including establishing appropriate instrument processing services. This article explores many of the specific steps an organization can take to ensure a safe care environment for patients and a safe working environment for volunteers. PMID:26819989

  11. Computational scalability of large size image dissemination

    NASA Astrophysics Data System (ADS)

    Kooper, Rob; Bajcsy, Peter

    2011-01-01

    We have investigated the computational scalability of image pyramid building needed for dissemination of very large image data. The sources of large images include high resolution microscopes and telescopes, remote sensing and airborne imaging, and high resolution scanners. The term 'large' is understood from a user perspective which means either larger than a display size or larger than a memory/disk to hold the image data. The application drivers for our work are digitization projects such as the Lincoln Papers project (each image scan is about 100-150MB or about 5000x8000 pixels with the total number to be around 200,000) and the UIUC library scanning project for historical maps from 17th and 18th century (smaller number but larger images). The goal of our work is understand computational scalability of the web-based dissemination using image pyramids for these large image scans, as well as the preservation aspects of the data. We report our computational benchmarks for (a) building image pyramids to be disseminated using the Microsoft Seadragon library, (b) a computation execution approach using hyper-threading to generate image pyramids and to utilize the underlying hardware, and (c) an image pyramid preservation approach using various hard drive configurations of Redundant Array of Independent Disks (RAID) drives for input/output operations. The benchmarks are obtained with a map (334.61 MB, JPEG format, 17591x15014 pixels). The discussion combines the speed and preservation objectives.

  12. Colonic stenting in malignant large bowel obstruction.

    PubMed

    Rajadurai, Vinita A; Levitt, Michael

    2016-06-01

    In patients who are surgical candidates, colonic stenting is beneficial for preoperative decompression in large bowel obstruction, as it can convert a surgical procedure from an emergent two-step approach into an elective one-step resection with a primary anastomosis. PMID:27398210

  13. Teaching Extra-Large Foreign Language Classes.

    ERIC Educational Resources Information Center

    Giauque, Gerald S.

    High quality instruction can be achieved in a foreign language classroom even though the class may be large by traditional standards, with as many as 60 students. Attitudes, class structure, classroom activities, and the teacher's role all play a part in this process in such classes. A positive attitude and enthusiasm on the teacher's part are…

  14. Analysis of large soil samples for actinides

    DOEpatents

    Maxwell, III; Sherrod L.

    2009-03-24

    A method of analyzing relatively large soil samples for actinides by employing a separation process that includes cerium fluoride precipitation for removing the soil matrix and precipitates plutonium, americium, and curium with cerium and hydrofluoric acid followed by separating these actinides using chromatography cartridges.

  15. Employment and Large Cities: Problems and Outlook.

    ERIC Educational Resources Information Center

    Bairoch, Paul

    1982-01-01

    This article traces the history of the emergence of large cities and examines the outlook for the future. It then answers questions about the effects of city size on general living conditions and on the various aspects of employment and the ways in which it might develop. (CT)

  16. Black Holes and the Large Hadron Collider

    ERIC Educational Resources Information Center

    Roy, Arunava

    2011-01-01

    The European Center for Nuclear Research or CERN's Large Hadron Collider (LHC) has caught our attention partly due to the film "Angels and Demons." In the movie, an antimatter bomb attack on the Vatican is foiled by the protagonist. Perhaps just as controversial is the formation of mini black holes (BHs). Recently, the American Physical Society…

  17. Aerodynamic beam generator for large particles

    DOEpatents

    Brockmann, John E.; Torczynski, John R.; Dykhuizen, Ronald C.; Neiser, Richard A.; Smith, Mark F.

    2002-01-01

    A new type of aerodynamic particle beam generator is disclosed. This generator produces a tightly focused beam of large material particles at velocities ranging from a few feet per second to supersonic speeds, depending on the exact configuration and operating conditions. Such generators are of particular interest for use in additive fabrication techniques.

  18. Conservative management of a large maxillary cyst.

    PubMed

    Rees, J S

    1997-01-01

    This article describes the treatment of a large maxillary cyst by root canal treatment and decompression using a hollow drain made from surgical suction tubing. The rationale behind the use of this technique is reviewed and its advantages highlighted. PMID:9477796

  19. Facing software complexity on large telescopes

    NASA Astrophysics Data System (ADS)

    Swart, Gerhard; Bester, Deon; Brink, Janus; Gumede, Clifford; Schalekamp, Hendrik J.

    2004-09-01

    The successful development of any complex control system requires a blend of good software management, an appropriate computer architecture and good software engineering. Due to the large number of controlled parts, high performance goals and required operational efficiency, the control systems for large telescopes are particularly challenging to develop and maintain. In this paper the authors highlight some of the specific challenges that need to be met by control system developers to meet the requirements within a limited budget and schedule. They share some of the practices applied during the development of the Southern African Large Telescope (SALT) and describe specific aspects of the design that contribute to meeting these challenges. The topics discussed include: development methodology, defining the level of system integration, computer architecture, interface management, software standards, language selection, user interface design and personnel selection. Time will reveal the full truth, but the authors believe that the significant progress achieved in commissioning SALT (now 6 months from telescope completion), can largely be attributed to the combined application of these practices and design concepts.

  20. Linking Large-Scale Reading Assessments: Comment

    ERIC Educational Resources Information Center

    Hanushek, Eric A.

    2016-01-01

    E. A. Hanushek points out in this commentary that applied researchers in education have only recently begun to appreciate the value of international assessments, even though there are now 50 years of experience with these. Until recently, these assessments have been stand-alone surveys that have not been linked, and analysis has largely focused on…