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Sample records for proviral hiv-dna load

  1. Quantification of HTLV-I proviral load in experimentally infected rabbits

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    Kindt Thomas J

    2005-05-01

    Full Text Available Abstract Background Levels of proviral load in HTLV-1 infected patients correlate with clinical outcome and are reasonably prognostic. Adaptation of proviral load measurement techniques is examined here for use in an experimental rabbit model of HTLV-1 infection. Initial efforts sought to correlate proviral load with route and dose of inoculation and with clinical outcome in this model. These methods contribute to our continuing goal of using the model to test treatments that alleviate virus infection. Results A real-time PCR assay was used to measure proviral load in blood and tissue samples from a series of rabbits infected using HTLV-1 inocula prepared as either cell-free virus particles, infected cells or blood, or by naked DNA injection. Proviral loads from asymptomatically infected rabbits showed levels corresponding to those reported for human patients with clinically silent HTLV-1 infections. Proviral load was comparably increased in 50% of experimentally infected rabbits that developed either spontaneous benign or malignant tumors while infected. Similarly elevated provirus was found in organs of rabbits with experimentally induced acute leukemia/lymphoma-like disease. Levels of provirus in organs taken at necropsy varied widely suggesting that reservoirs of infections exist in non-lymphoid organs not traditionally thought to be targets for HTLV-1. Conclusion Proviral load measurement is a valuable enhancement to the rabbit model for HTLV-1 infection providing a metric to monitor clinical status of the infected animals as well as a means for the testing of treatment to combat infection. In some cases proviral load in blood did not reflect organ proviral levels, revealing a limitation of this method for monitoring health status of HTLV-1 infected individuals.

  2. Quantification of HTLV-I proviral load in experimentally infected rabbits

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    Zhao, Tong-Mao; Hague, Bishop; Caudell, David L; Simpson, R Mark; Kindt, Thomas J

    2005-01-01

    Background Levels of proviral load in HTLV-1 infected patients correlate with clinical outcome and are reasonably prognostic. Adaptation of proviral load measurement techniques is examined here for use in an experimental rabbit model of HTLV-1 infection. Initial efforts sought to correlate proviral load with route and dose of inoculation and with clinical outcome in this model. These methods contribute to our continuing goal of using the model to test treatments that alleviate virus infection. Results A real-time PCR assay was used to measure proviral load in blood and tissue samples from a series of rabbits infected using HTLV-1 inocula prepared as either cell-free virus particles, infected cells or blood, or by naked DNA injection. Proviral loads from asymptomatically infected rabbits showed levels corresponding to those reported for human patients with clinically silent HTLV-1 infections. Proviral load was comparably increased in 50% of experimentally infected rabbits that developed either spontaneous benign or malignant tumors while infected. Similarly elevated provirus was found in organs of rabbits with experimentally induced acute leukemia/lymphoma-like disease. Levels of provirus in organs taken at necropsy varied widely suggesting that reservoirs of infections exist in non-lymphoid organs not traditionally thought to be targets for HTLV-1. Conclusion Proviral load measurement is a valuable enhancement to the rabbit model for HTLV-1 infection providing a metric to monitor clinical status of the infected animals as well as a means for the testing of treatment to combat infection. In some cases proviral load in blood did not reflect organ proviral levels, revealing a limitation of this method for monitoring health status of HTLV-1 infected individuals. PMID:15910683

  3. Single nucleotide polymorphisms in the bovine MHC region of Japanese Black cattle are associated with bovine leukemia virus proviral load.

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    Takeshima, Shin-Nosuke; Sasaki, Shinji; Meripet, Polat; Sugimoto, Yoshikazu; Aida, Yoko

    2017-04-04

    Bovine leukemia virus (BLV) is the causative agent of enzootic bovine leukosis, a malignant B cell lymphoma that has spread worldwide and causes serious problems for the cattle industry. The BLV proviral load, which represents the BLV genome integrated into host genome, is a useful index for estimating disease progression and transmission risk. Here, we conducted a genome-wide association study to identify single nucleotide polymorphisms (SNPs) associated with BLV proviral load in Japanese Black cattle. The study examined 93 cattle with a high proviral load and 266 with a low proviral load. Three SNPs showed a significant association with proviral load. One SNP was detected in the CNTN3 gene on chromosome 22, and two (which were not in linkage disequilibrium) were detected in the bovine major histocompatibility complex region on chromosome 23. These results suggest that polymorphisms in the major histocompatibility complex region affect proviral load. This is the first report to detect SNPs associated with BLV proviral load in Japanese Black cattle using whole genome association study, and understanding host factors may provide important clues for controlling the spread of BLV in Japanese Black cattle.

  4. Risk factors associated with increased bovine leukemia virus proviral load in infected cattle in Japan from 2012 to 2014.

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    Ohno, Ayumu; Takeshima, Shin-nosuke; Matsumoto, Yuki; Aida, Yoko

    2015-12-02

    Bovine leukemia virus (BLV) is the causative agent of enzootic bovine leukosis, a malignant B cell lymphoma. BLV has spread worldwide and causes serious problems. After infection, the BLV genome is integrated into the host DNA and can be amplified during periods of latency. We previously designed degenerate primers using the Coordination of Common Motifs (CoCoMo) algorithm to establish a new quantitative real-time PCR method (BLV-CoCoMo-qPCR-2) of measuring the proviral load of both known and novel BLV variants. Here, we aimed to examine the correlation between proviral load and risk factors for BLV infection, such as breeding systems, parousity, and colostrum feeding. Blood and serum samples were collected from 83 BLV-positive farms in 22 prefectures of Japan, and the BLV proviral load and anti-BLV antibody levels were measured. BLV was detected in 73.3% (1039/1,417) of cattle by BLV-CoCoMo-qPCR-2 and the provirus was detected in 93 of 1039 antibody-negative samples. The results showed that the proviral load increased with progression of lymphocytosis. Next, the risk factors associated with increasing BLV infection rate were examined along with any association with proviral load. The proviral load was higher in cattle with lymphocytosis than in healthy cattle, and higher in multiparous cows than in nulliparous cows. Finally, proviral loads were higher in contact breeding systems than in non-contact breeding systems. Taken together, these findings may help to formulate a plan for eliminating BLV from contaminated farms. This is the first nationwide study to estimate BLV proviral load in Japanese cattle. Copyright © 2015 Elsevier B.V. All rights reserved.

  5. Telomere Length, Proviral Load and Neurologic Impairment in HTLV-1 and HTLV-2-Infected Subjects

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    Benjamin Usadi

    2016-08-01

    Full Text Available Short or damaged telomeres have been implicated in degenerative conditions. We hypothesized that analysis of telomere length (TL in human T-cell lymphotropic virus (HTLV infection and HTLV-associated neuropathy might provide clues to the etiology of HTLV-associated disease and viral dynamics. A subset of 45 human T-cell lymphotropic virus type 1 (HTLV-1, 45 human T-cell lymphotropic virus type 2 (HTLV-2, and 45 seronegative subjects was selected from the larger HTLV Outcomes Study (HOST cohort, matched on age, sex and race/ethnicity. Telomere-to-single-copy gene (T/S ratio (a measure of TL and HTLV-1 and HTLV-2 proviral loads were measured in peripheral blood mononuclear cells (PBMCs using quantitative PCR (qPCR. Vibration sensation measured by tuning fork during neurologic examinations performed as part of the HOST study allowed for an assessment of peripheral neuropathy. TL was compared between groups using t-tests, linear and logistic regression. Mean T/S ratio was 1.02 ± 0.16 in HTLV-1, 1.03 ± 0.17 in HTLV-2 and 0.99 ± 0.18 in HTLV seronegative subjects (p = 0.322. TL was not associated with HTLV-1 or -2 proviral load. Shorter TL was significantly associated with impaired vibration sense in the HTLV-2 positive group only. Overall, we found no evidence that telomere length was affected by chronic HTLV-1 and HTLV-2 infection. That TL was only associated with peripheral neuropathy in the HTLV-2-positive group is intriguing, but should be interpreted cautiously. Studies with larger sample size and telomere length measurement in lymphocyte subsets may clarify the relationship between TL and HTLV-infection.

  6. Evaluation of HTLV-1 activity in HAM/TSP patients using proviral load and Tax mRNA expression after In Vitro lymphocyte activation.

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    Yari, Atefeh; Rezaee, Seyyed Abdolrahim; Valizadeh, Narges; Rajaee, Taraneh; Jazayeri, Seyyed Mohammad; Soltani, Mojdeh; Norouzi, Mehdi

    2014-07-01

    HTLV-1 is the first human retrovirus that has been recognized and is associated with HAM/TSP and ATLL. Studies have shown that less than five percent of HTLV-1 infected carriers develop HAM/TSP or ATLL and about ninety-five percent remain asymptomatic. Therefore, the proviral load with Tax may affect cellular genes such as cytokines and oncogenes, as well as involve in pathogenicity. Thirty HAM/TSP patients, thirty HTLV-1 healthy carriers, and MT-2 cell line were evaluated for HTLV-1 activity. PBMCs were isolated and activated using PMA and ionomycine. Real-time PCR and TaqMan methods were performed using specific primers and fluorescence probes for Tax expression and proviral load assessment. B2microglobulin (β2m) and albumin were used as controls in Tax expression and in proviral load, respectively. An insignificant increase in Tax expression was observed in rest PBMCs of HAM/TSP patients compared to healthy carriers. However, after lymphocyte activation there was a significant increase in Tax expression in HAM/TSP patients (P=0.042). The Proviral load in patients was significantly higher than in carriers. Moreover, there was a significant correlation between Tax mRNA expression in activated PBMCs and proviral load (R=0.37, P=0.012). Although proviral load had been addressed as a valuable index for monitoring HTLV-1 infected subjects, the results of this study demonstrated that Tax expression in activated PBMCs along with proviral load assessment in HAM/TSP patients are a more reliable factor for determining the prognosis and monitoring healthy carriers and HAM/TSP patients.

  7. Identification of bovine leukocyte antigen class II haplotypes associated with variations in bovine leukemia virus proviral load in Japanese Black cattle.

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    Miyasaka, T; Takeshima, S-n; Jimba, M; Matsumoto, Y; Kobayashi, N; Matsuhashi, T; Sentsui, H; Aida, Y

    2013-02-01

    Bovine leukemia virus (BLV) is the etiological agent of enzootic bovine leukosis, which is the most common neoplastic disease of cattle. Bovine leukocyte antigen (BoLA) is strongly involved in the subclinical progression of BLV infections. Recent studies show that the BoLA-DRB3 gene might play a direct role in controlling the number of BLV-infected peripheral B lymphocytes in vivo in Holstein cattle. However, the specific BoLA class II allele and DRB3-DQA1 haplotypes determining the BLV proviral load in Japanese Black cattle are yet to be identified. In this study, we focused on the association of BLV proviral load and polymorphism of BoLA class II in Japanese Black cattle. We genotyped 186 BLV-infected, clinically normal cattle for BoLA-DRB3 and BoLA-DQA1 using a polymerase chain reaction-sequence-based typing method. BoLA-DRB3*0902 and BoLA-DRB3*1101 were associated with a low proviral load (LPVL), and BoLA-DRB3*1601 was associated with a high proviral load (HPVL). Furthermore, BoLA-DQA1*0204 and BoLA-DQA1*10012 were related to LPVL and HPVL, respectively. Furthermore, we confirmed the correlation between the DRB3-DQA1 haplotype and BLV proviral load. Two haplotypes, namely 0902B or C (DRB3*0902-DQA1*0204) and 1101A (DRB3*1101-DQA1*10011), were associated with a low BLV proviral load, whereas one haplotype 1601B (DRB3*1601-DQA1*10012) was associated with a high BLV proviral load. We conclude that resistance is a dominant trait and susceptibility is a recessive trait. Additionally, resistant alleles were common between Japanese Black and Holstein cattle, and susceptible alleles differed. This is the first report to identify an association between the DRB3-DQA1 haplotype and variations in BLV proviral load. © 2012 John Wiley & Sons A/S.

  8. Comparison of HTLV-I Proviral Load in Adult T Cell Leukemia/Lymphoma (ATL), HTLV-I-Associated Myelopathy (HAM-TSP) and Healthy Carriers.

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    Akbarin, Mohammad Mehdi; Rahimi, Hossein; Hassannia, Tahereh; Shoja Razavi, Ghazaleh; Sabet, Faezeh; Shirdel, Abbas

    2013-03-01

    Human T Lymphocyte Virus Type one (HTLV-I) is a retrovirus that infects about 10-20 million people worldwide. Khorasan province in Iran is an endemic area. The majority of HTLV-I-infected individuals sustain healthy carriers but small proportion of infected population developed two progressive diseases: HAM/TSP and ATL. The proviral load could be a virological marker for disease monitoring, therefore in the present study HTLV-I proviral load has been evaluated in ATL and compared to HAM/TSP and healthy carriers. In this case series study, 47 HTLV-I infected individuals including 13 ATL, 23 HAM/TSP and 11 asymptomatic subjects were studied. Peripheral blood mononuclear cells (PBMCs) were investigated for presence of HTLV-I DNA provirus by PCR using LTR and Tax fragments. Then in infected subjects, HTLV-I proviral load was measured using real time PCR TaqMan method. The average age of patients in ATL was 52±8, in HAM/TSP 45.52±15.17 and in carrier's 38.65±14.9 years which differences were not statistically significant. The analysis of data showed a significant difference in mean WBC among study groups (ATL vs HAM/TSP and carriers P=0.0001). Moreover, mean HTLV-I proviral load was 11967.2 ± 5078, 409 ± 71.3 and 373.6 ± 143.3 in ATL, HAM/TSP and Healthy Carriers, respectively. The highest HTLV-I proviral load was measured in ATL group that had a significant correlation with WBC count (R=0.495, P=0.001). The proviral load variations between study groups was strongly significant (ATL vs carrier P=0.0001; ATL vs HAM/TSP P= 0.0001 and HAM/TSP vs carriers PTSP and healthy carriers. Therefore, HTLV-I proviral load is a prognostic factor for development of HTLV-I associated diseases and can be used as a monitoring marker for the efficiency of therapeutic regime.

  9. Association between HLA Class I Alleles and Proviral Load in HTLV-I Associated Myelopathy/Tropical Spastic Paraperesis (HAM/TSP) Patients in Iranian Population.

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    Taghaddosi, Mahdi; Rezaee, S A Rahim; Rafatpanah, Houshang; Rajaei, Taraneh; Farid Hosseini, Reza; Narges, Valizadeh

    2013-03-01

    The aim of this study was to investigate the association between HLA class I alleles (HLA-A*02, HLA-A*24, HLA-Cw*08, HLA-B5401) and proviral load in HTLV-I associated myelopathy/tropical spastic paraperesis (HAM/TSP) patients in Iranian population. 20 new cases of HAM/TSP patients and 30 HTLV-I infected healthy carriers were recruited. Peripheral blood samples were collected. Peripheral blood mononuclear cells (PBMCs) were isolated. DNA was extracted from PBMC.HTLV-I proviral load was calculated by Taqman quantitative real time polymerase chain reaction (qRT-PCR). PCR sequence-specific primer (PCR-SSP) reactions were performed to detect HLA-A, HLA-B and, HLA-Cw alleles. There was no significant difference in sex and age between asymptomatic and HAM/TSP group. The Mann-Whitney U test was used to compare proviral load between HAM/TSP patients and healthy carrier. Provirus load of HAM/TSP patients was significantly higher than that of HCs (P=0.003, Mann-Whitney U test).Odd ratio was calculated to determine association between class I alleles including (HLA-A*02, HLA-A*24, HLA-Cw*08) and risk of HAM/TSP development. We couldn't find any association between these class I alleles and risk of HAM/TSP development in our study. In our survey HLA-A*02, HLA-A24, HLA-Cw*08 didn't have protective effect on proviral load (P=0.075, P=0.060 and 0.650 Mann-Whitney U test respectively). In conclusion, certain HLA alleles with protective effect in one population may have not similar effect in other population. This may be because of pathogen polymorphism or host genetic heterogeneity and allele frequency in desired population.

  10. High HTLV-1 proviral load, a marker for HTLV-1-associated myelopathy/tropical spastic paraparesis, is also detected in patients with infective dermatitis associated with HTLV-1

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    Primo, J.; Siqueira, I.; Nascimento, M.C.F.; Oliveira, M.F.; Farre, L.; Carvalho, E.M.; Bittencourt, A.L.

    2010-01-01

    Salvador (BA, Brazil) is an endemic area for human T-cell lymphotrophic virus type 1 (HTLV-1). The overall prevalence of HTLV-1 infection in the general population has been estimated to be 1.76%. HTLV-1 carriers may develop a variety of diseases such as adult T-cell leukemia/lymphoma, HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) and infective dermatitis associated with HTLV-1 (IDH). IDH is a chronic and severe form of childhood exudative and infective dermatitis involving mainly the scalp, neck and ears. It has recently been observed that 30% of patients with IDH develop juvenile HAM/TSP. The replication of HTLV-1 has been reported to be greater in adult HAM/TSP patients than in asymptomatic HTLV-1 carriers. In the current study, the proviral load of 28 children and adolescents with IDH not associated with HAM/TSP was determined and the results were compared to those obtained in 28 HTLV-1 adult carriers and 28 adult patients with HAM/TSP. The proviral load in IDH patients was similar to that of patients with HAM/TSP and much higher than that found in HTLV-1 carriers. The high levels of proviral load in IDH patients were not associated with age, duration of illness, duration of breast-feeding, or activity status of the skin disease. Since proviral load is associated with neurological disability, these data support the view that IDH patients are at high risk of developing HAM/TSP. PMID:19578703

  11. Human T cell lymphotropic virus type 1 (HTLV-1) proviral load of HTLV-associated myelopathy/tropical spastic paraparesis (HAM/TSP) patients according to new diagnostic criteria of HAM/TSP.

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    Grassi, Maria Fernanda Rios; Olavarria, Viviana Nilla; Kruschewsky, Ramon de Almeida; Mascarenhas, Rita Elizabeth; Dourado, Inês; Correia, Luis C L; de Castro-Costa, Carlos Maurício; Galvão-Castro, Bernardo

    2011-07-01

    A high human T-cell lymphotropic virus type 1 (HTLV-1) proviral load is described in HTLV-1-associated diseases, especially HAM/TSP. However, the cut-off value to define high levels of HTLV-1 proviral load is not well established. 281 HTLV-1-infected patients from the HTLV reference center in Salvador, Brazil, were followed from 2005 to 2008. Patients were classified as asymptomatic, possible-, probable-, and definite-HAM/TSP, in accordance with diagnostic criteria proposed by De Castro-Costa et al. (2006): AIDS Res Hum Retroviruses 22:931-935. HTLV-1 proviral load was determined using real-time PCR. A receiver operator characteristic (ROC) curve was constructed using only asymptomatic individuals and definite-HAM/TSP patients. The ROC curve was used to predict the proviral load level that differentiates these two groups. Out of 281 patients, 189 were asymptomatic and 92 were diagnosed with HAM/TSP (22 possible, 23 probable, 47 definite). The mean HTLV-1 proviral load was higher in possible- (89,104 ± 93,006 copies/106 PBMC), -probable (175,854 ± 128,083 copies/106 PBMC), and definite-HAM/TSP patients (150,667 ± 122,320 copies/106 PBMC),when compared to asymptomatic individuals (27,178 ± 41,155 copies/106 PBMC) (P TSP groups showed the highest proviral loads in probable-HAM/TSP patients, yet the differences in mean values were not statistically significant. The ROC curve suggested a value of 49,865 copies/106 PBMC, with 87% sensitivity (95% CI ¼ 74-95) and 81% specificity (95% CI ¼ 75-86), as the best proviral load cut-off point to differentiate definite HAM/TSP patients from asymptomatic individuals. HTLV-1 proviral loads are higher in groups of infected patients with eurological symptoms and may represent a relevant biological marker of disease progression.

  12. Proviral load and the balance of serum cytokines in HTLV-1-asymptomatic infection and in HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP).

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    Starling, Ana Lúcia Borges; Martins-Filho, Olindo Assis; Lambertucci, José Roberto; Labanca, Ludimila; de Souza Pereira, Silvio Roberto; Teixeira-Carvalho, Andréa; Martins, Marina Lobato; Ribas, João Gabriel; Carneiro-Proietti, Anna Bárbara F; Gonçalves, Denise Utsch

    2013-01-01

    This study compared the proviral load and the plasma cytokine profiles (interleukin-IL-2, IL-4, IL-6, IL-10, TNF-α, IFN-γ) in 87 HTLV-1-infected individuals, including 28 with HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP), 32 with possible pHAM/TSP and 27 asymptomatic carriers (AC). The control group was composed by 21 HTLV-1-seronegative individuals. Our finding demonstrated that HAM/TSP group presented higher proviral load as compared to all other HTLV-1 groups (pTSP group showed higher serum concentration of IL-6 (p=0.0009) as compared to all other groups. Moreover, higher serum concentration of IFN-γ (p=0.0118) and IL-4 (p=0.0166) were observed in HAM/TSP group as compared to the healthy controls. Additionally, the HAM/TSP group also showed higher serum concentration of TNF-α (p=0.0239) and IFN-γ (p=0.0118) as compared to AC. No differences in the serum concentration of IL-2 and IL-10 were observed among the groups. The analysis of cytokine balance demonstrated that HAM/TSP presented higher pro-inflammatory profile with enhanced IFN-γ/IL-10 and IFN-γ/IL-4 ratio as compared to AC and pHAM/TSP. Further analysis pointed out to a positive correlation between the IFN-γ response and the proviral load in AC. Conversely, a negative association between TNF-α and IL-2 with the proviral load was the hallmark of HAM/TSP group. These findings suggested that the proviral load and the pro-inflammatory cytokine profile may be independent events in the peripheral blood of HAM/TSP individuals. The knowledge about the existence of individual virological/immunological behavior upon HTLV-1 infection, may guide to the establishment of more effective therapeutic interventions. Copyright © 2012 Elsevier B.V. All rights reserved.

  13. Evaluation of the role of TAX, HBZ, and HTLV-1 proviral load on the survival of ATLL patients.

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    Akbarin, Mohammad Mehdi; Shirdel, Abbas; Bari, Alireza; Mohaddes, Seyedeh Tahereh; Rafatpanah, Houshang; Karimani, Ehsan Ghayour; Etminani, Kobra; Golabpour, Amin; Torshizi, Reza

    2017-06-01

    Adult T-cell leukemia/lymphoma (ATLL) is an aggressive malignancy with very poor prognosis and short survival, caused by the human T-lymphotropic virus type-1 (HTLV-1). The HTLV-1 biomarkers trans-activator x (TAX) and HTLV-1 basic leucine zipper factor (HBZ) are main oncogenes and life-threatening elements. This study aimed to assess the role of the TAX and HBZ genes and HTLV-1 proviral load (PVL) in the survival of patients with ATLL. Forty-three HTLV-1-infected individuals, including 18 asymptomatic carriers (AC) and 25 ATLL patients (ATLL), were evaluated between 2011 and 2015. The mRNA expression of TAX and HBZ and the HTLV-1 PVL were measured by quantitative PCR. Significant differences in the mean expression levels of TAX and HBZ were observed between the two study groups (ATLL and AC, P=0.014 and P=0.000, respectively). In addition, the ATLL group showed a significantly higher PVL than AC (P=0.000). There was a significant negative relationship between PVL and survival among all study groups (P=0.047). The HTLV-1 PVL and expression of TAX and HBZ were higher in the ATLL group than in the AC group. Moreover, a higher PVL was associated with shorter survival time among all ATLL subjects. Therefore, measurement of PVL, TAX, and HBZ may be beneficial for monitoring and predicting HTLV-1-infection outcomes, and PVL may be useful for prognosis assessment of ATLL patients. This research demonstrates the possible correlation between these virological markers and survival in ATLL patients.

  14. The FAS-670 AA genotype is associated with high proviral load in peruvian HAM/TSP patients.

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    Rosado, Jason; Morales, Sandra; López, Giovanni; Clark, Daniel; Verdonck, Kristien; Gotuzzo, Eduardo; Van Camp, Guy; Talledo, Michael

    2017-04-01

    Human T-lymphotropic virus 1 (HTLV-1) is the etiologic agent of the HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). Apoptosis is a mechanism of defense elicited by many triggers, including cross-linking of the FAS receptor expressed in viruses-infected cells, and the ligand FASL presented by T-cytotoxic cells. As HAM/TSP has been associated with high levels of proviral load (PVL), we hypothesized that certain genotypes of single-nucleotide polymorphisms (SNPs) associated with a decreased protein expression of FAS and FASL could be risk factors for this disease. Three SNPs: FAS-670A/G (rs1800682), FAS-1377G/A (rs2234767), and FASL-844C/T (rs763110) were analyzed in 73 HAM/TSP patients and 143 HTLV-1 asymptomatic carriers. Ancestry informative markers were used to adjust for ethnicity through a principal component analysis. Gender, age, PVL, and the first three principal components were used as covariates. The FAS/FASL genotype distribution was not associated with HAM/TSP presence (P-> 0.05). The FAS-670 AA genotype was associated with high PVL in comparison to FAS-670 GG in HAM/TSP patients (P = 0.015), while in asymptomatic carriers low levels of PVL were observed (P > 0.05). Our findings suggest that rs1800682, rs2234767, and rs763110 genotypes are not associated with the presence of HAM/TSP, but that the FAS-670 AA genotype can promote higher PVL values in HAM/TSP patients. J. Med. Virol. 89:726-731, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  15. Dynamic interaction between STLV-1 proviral load and T-cell response during chronic infection and after immunosuppression in non-human primates.

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    Sandrine Souquière

    Full Text Available We used mandrills (Mandrillus sphinx naturally infected with simian T-cell leukemia virus type 1 (STLV-1 as a model for evaluating the influence of natural STLV-1 infection on the dynamics and evolution of the immune system during chronic infection. Furthermore, in order to evaluate the role of the immune system in controlling the infection during latency, we induced immunosuppression in the infected monkeys. We first showed that the STLV-1 proviral load was higher in males than in females and increased significantly with the duration of infection: mandrills infected for 10-6 years had a significantly higher proviral load than those infected for 2-4 years. Curiously, this observation was associated with a clear reduction in CD4+ T-cell number with age. We also found that the percentage of CD4(+ T cells co-expressing the activation marker HLA-DR and the mean percentage of CD25(+ in CD4(+ and CD8(+ T cells were significantly higher in infected than in uninfected animals. Furthermore, the STLV-1 proviral load correlated positively with T-cell activation but not with the frequency of T cells secreting interferon gamma in response to Tax peptides. Lastly, we showed that, during immunosuppression in infected monkeys, the percentages of CD8(+ T cells expressing HLA-DR(+ and of CD4(+ T cells expressing the proliferation marker Ki67 decreased significantly, although the percentage of CD8(+ T cells expressing HLA-DR(+ and Ki67 increased significantly by the end of treatment. Interestingly, the proviral load increased significantly after immunosuppression in the monkey with the highest load. Our study demonstrates that mandrills naturally infected with STLV-1 could be a suitable model for studying the relations between host and virus. Further studies are needed to determine whether the different compartments of the immune response during infection induce the long latency by controlling viral replication over time. Such studies would provide important

  16. BLV-CoCoMo-qPCR: Quantitation of bovine leukemia virus proviral load using the CoCoMo algorithm

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    Matoba Kazuhiro

    2010-11-01

    Full Text Available Abstract Background Bovine leukemia virus (BLV is closely related to human T-cell leukemia virus (HTLV and is the etiological agent of enzootic bovine leukosis, a disease characterized by a highly extended course that often involves persistent lymphocytosis and culminates in B-cell lymphomas. BLV provirus remains integrated in cellular genomes, even in the absence of detectable BLV antibodies. Therefore, to understand the mechanism of BLV-induced leukemogenesis and carry out the selection of BLV-infected animals, a detailed evaluation of changes in proviral load throughout the course of disease in BLV-infected cattle is required. The aim of this study was to develop a new quantitative real-time polymerase chain reaction (PCR method using Coordination of Common Motifs (CoCoMo primers to measure the proviral load of known and novel BLV variants in clinical animals. Results Degenerate primers were designed from 52 individual BLV long terminal repeat (LTR sequences identified from 356 BLV sequences in GenBank using the CoCoMo algorithm, which has been developed specifically for the detection of multiple virus species. Among 72 primer sets from 49 candidate primers, the most specific primer set was selected for detection of BLV LTR by melting curve analysis after real-time PCR amplification. An internal BLV TaqMan probe was used to enhance the specificity and sensitivity of the assay, and a parallel amplification of a single-copy host gene (the bovine leukocyte antigen DRA gene was used to normalize genomic DNA. The assay is highly specific, sensitive, quantitative and reproducible, and was able to detect BLV in a number of samples that were negative using the previously developed nested PCR assay. The assay was also highly effective in detecting BLV in cattle from a range of international locations. Finally, this assay enabled us to demonstrate that proviral load correlates not only with BLV infection capacity as assessed by syncytium formation, but

  17. Evaluation of HTLV-1 HBZ and proviral load, together with host IFN λ3, in pathogenesis of HAM/TSP.

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    Mozhgani, Sayed-Hamidreza; Jaberi, Najmeh; Rezaee, Seyed Abdolrahim; Bustani, Reza; Jazayeri, Seyed Mohammad; Akbarin, Mohammad Mehdi; Milani, Saeideh; Tarokhian, Hanieh; Norouzi, Mehdi

    2017-06-01

    Human T-cell lymphotropic virus 1 (HTLV-1) is associated with two progressive diseases: HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) and adult T-cell leukemia/lymphoma (ATLL). Although HTLV-1 proviral load (PVL) has been introduced as a risk factor for these diseases' progression, it is not sufficient on its own to yield an accurate estimation of the outcome of the infection. In the present study, PVL and HTLV-1 basic leucine zipper factor (HBZ) expression level as viral factors, and IFN λ3 as a host factor, were evaluated in HAM/TSP patients and HTLV-1 asymptomatic carriers (ACs). During 2014-2015, 12 HAM/TSP patients and 18 ACs who had been referred to the HTLV-1 Clinic, Ghaem Hospital, Mashhad University of Medical Sciences (MUMS), Mashhad, Iran, were enrolled in this study. Peripheral blood mononuclear cells (PBMCs) were isolated and the DNA and mRNA were extracted for quantification of HBZ, IFN λ3 expression, and PVL using real-time PCR (TaqMan method). Although the PVL was higher in the HAM/TSP group, with a 94% confidence interval, there were no considerable differences in terms of HBZ mRNA and PVL between ACs and HAM patients. IFN λ3 expression in the HAM/TSP group was significantly higher than in the ACs (P = 0.02). To the best of our knowledge, no study has evaluated the expression level of IFN λ3 in HTLV-1 positive patients. The immune response against HTLV-1 viral antigens and virulent factors will therefore further refine our knowledge of interactions between the virus and host in the pathogenesis of HTLV-1-related disorders. The virus PVL and the host IFN λ3 can be used as pathogenic factors of HTLV-1 infected patients at risk of HAM/TSP manifestation. J. Med. Virol. 89:1102-1107, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  18. Interferon Beta-1a Improves Urinary Symptoms, Reduces Proviral Load, and Modifies the Immune Response in a Patient with HAM/TSP.

    Science.gov (United States)

    Costa, Davi Tanajura; Sundberg, Michael; Passos, Lúcia; Muniz, André Luiz; Santos, Silvane

    2012-01-01

    The human T-cell lymphotropic virus type 1 (HTLV-1) is the known causative agent of a chronic neurologic condition known as HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). Although several therapies have been evaluated for HAM/TSP, none have been approved for use in humans. In this paper, we describe a 55-year-old female patient with HAM/TSP who was treated with interferon beta-1a. This patient, in comparison to 20 female patients with HAM/TSP who were not treated, showed improvement in urinary symptoms over four years of therapy, as well as a reduction in HTLV-1 proviral load and serum cytokine levels typically observed in HAM/TSP. This improved outcome merits further controlled studies on the use and efficacy of interferon beta-1a as a therapy for HAM/TSP.

  19. Proviral Loads and Clonal Expansion of HTLV-1-Infected Cells following Vertical Transmission: A 10-Year Follow-Up of Children in Jamaica

    Science.gov (United States)

    Umeki, Kazumi; Hisada, Michie; Maloney, Elizabeth M.; Hanchard, Barrie; Okayama, Akihiko

    2009-01-01

    Objective Few studies have specifically examined proviral load (PVL) and clonal evolution of human T-lymphotropic virus type 1 (HTLV-1)-infected cells in vertically infected children. Methods Sequential samples (from ages 1 to 16 years) from 3 HTLV-1-infected children (cases A, B and C) in the Jamaica Mother Infant Cohort Study were analyzed for their PVL and clonal expansion of HTLV-1-infected cells in peripheral blood mononuclear cells (PBMCs) by inverse-long PCR. Results The baseline PVL (per 100,000 PBMCs) of case A was 260 (at 1 year of age) and of case B it was 1,867 (at 3 years of age), and they remained constant for more than 10 years. Stochastic patterns of clonal expansion of HTLV-1-infected cells were predominately detected. In contrast, case C, who had lymphadenopathy, seborrheic dermatitis and hyperreflexia, showed an increase in PVL from 2,819 at 1.9 years to 13,358 at 13 years of age, and expansion of 2 dominant clones. Conclusion The clonal expansion of HTLV-1-infected cells is induced in early childhood after infection acquired from their mothers. Youths with high PVL and any signs and symptoms associated with HTLV-1 infection should be closely monitored. PMID:19468234

  20. Characterization of HIV-1 Near Full-Length Proviral Genome Quasispecies from Patients with Undetectable Viral Load Undergoing First-Line HAART Therapy

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    Brunna M. Alves

    2017-12-01

    Full Text Available Increased access to highly active antiretroviral therapy (HAART by human immunodeficiency virus postive (HIV+ individuals has become a reality worldwide. In Brazil, HAART currently reaches over half of HIV-infected subjects. In the context of a remarkable HIV-1 genetic variability, highly related variants, called quasispecies, are generated. HIV quasispecies generated during infection can influence virus persistence and pathogenicity, representing a challenge to treatment. However, the clinical relevance of minority quasispecies is still uncertain. In this study, we have determined the archived proviral sequences, viral subtype and drug resistance mutations from a cohort of HIV+ patients with undetectable viral load undergoing HAART as first-line therapy using next-generation sequencing for near full-length virus genome (NFLG assembly. HIV-1 consensus sequences representing NFLG were obtained for eleven patients, while for another twelve varying genome coverage rates were obtained. Phylogenetic analysis showed the predominance of subtype B (83%; 19/23. Considering the minority variants, 18 patients carried archived virus harboring at least one mutation conferring antiretroviral resistance; for six patients, the mutations correlated with the current ARVs used. These data highlight the importance of monitoring HIV minority drug resistant variants and their clinical impact, to guide future regimen switches and improve HIV treatment success.

  1. HTLV-1 Tax-Specific CTL Epitope-Pulsed Dendritic Cell Therapy Reduces Proviral Load in Infected Rats with Immune Tolerance against Tax.

    Science.gov (United States)

    Ando, Satomi; Hasegawa, Atsuhiko; Murakami, Yuji; Zeng, Na; Takatsuka, Natsuko; Maeda, Yasuhiro; Masuda, Takao; Suehiro, Youko; Kannagi, Mari

    2017-02-01

    Adult T cell leukemia/lymphoma (ATL), a CD4(+) T cell malignancy with a poor prognosis, is caused by human T cell leukemia virus type 1 (HTLV-1) infection. High proviral load (PVL) is a risk factor for the progression to ATL. We previously reported that some asymptomatic carriers had severely reduced functions of CTLs against HTLV-1 Tax, the major target Ag. Furthermore, the CTL responses tended to be inversely correlated with PVL, suggesting that weak HTLV-1-specific CTL responses may be involved in the elevation of PVL. Our previous animal studies indicated that oral HTLV-1 infection, the major route of infection, caused persistent infection with higher PVL in rats compared with other routes. In this study, we found that Tax-specific CD8(+) T cells were present, but not functional, in orally infected rats as observed in some human asymptomatic carriers. Even in the infected rats with immune unresponsiveness against Tax, Tax-specific CTL epitope-pulsed dendritic cell (DC) therapy reduced the PVL and induced Tax-specific CD8(+) T cells capable of proliferating and producing IFN-γ. Furthermore, we found that monocyte-derived DCs from most infected individuals still had the capacity to stimulate CMV-specific autologous CTLs in vitro, indicating that DC therapy may be applicable to most infected individuals. These data suggest that peptide-pulsed DC immunotherapy will be useful to induce functional HTLV-1-specific CTLs and decrease PVL in infected individuals with high PVL and impaired HTLV-1-specific CTL responses, thereby reducing the risk of the development of ATL. Copyright © 2017 by The American Association of Immunologists, Inc.

  2. Low Proviral Load is Associated with Indeterminate Western Blot Patterns in Human T-Cell Lymphotropic Virus Type 1 Infected Individuals: Could Punctual Mutations be Related?

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    Cánepa, Camila; Salido, Jimena; Ruggieri, Matías; Fraile, Sindy; Pataccini, Gabriela; Berini, Carolina; Biglione, Mirna

    2015-10-28

    indeterminate Western blot (WB) patterns are a major concern for diagnosis of human T-cell lymphotropic virus type 1 (HTLV-1) infection, even in non-endemic areas. (a) to define the prevalence of indeterminate WB among different populations from Argentina; (b) to evaluate if low proviral load (PVL) is associated with indeterminate WB profiles; and (c) to describe mutations in LTR and tax sequence of these cases. Among 2031 samples, 294 were reactive by screening. Of them, 48 (16.3%) were WB indeterminate and of those 15 (31.3%) were PCR+. Quantitative real-time PCR (qPCR) was performed to 52 HTLV-1+ samples, classified as Group 1 (G1): 25 WB+ samples from individuals with pathologies; Group 2 (G2): 18 WB+ samples from asymptomatic carriers (AC); and Group 3 (G3): 9 seroindeterminate samples from AC. Median PVL was 4.78, 2.38, and 0.15 HTLV-1 copies/100 PBMCs, respectively; a significant difference (p=0.003) was observed. Age and sex were associated with PVL in G1 and G2, respectively. Mutations in the distal and central regions of Tax Responsive Elements (TRE) 1 and 2 of G3 were observed, though not associated with PVL.The 8403A>G mutation of the distal region, previously related to high PVL, was absent in G3 but present in 50% of WB+ samples (p = 0.03). indeterminate WB results confirmed later as HTLV-1 positive may be associated with low PVL levels. Mutations in LTR and tax are described; their functional relevance remains to be determined.

  3. T-cell tropism of simian T-cell leukaemia virus type 1 and cytokine profiles in relation to proviral load and immunological changes during chronic infection of naturally infected mandrills (Mandrillus sphinx).

    Science.gov (United States)

    Souquière, Sandrine; Mouinga-Ondeme, Augustin; Makuwa, Maria; Beggio, Paola; Radaelli, Antonia; De Giuli Morghen, Carlo; Mortreux, Franck; Kazanji, Mirdad

    2009-08-01

    Although a wide variety of non-human primates are susceptible to simian T-cell leukaemia virus type 1 (STLV-1), little is known about the virological or molecular determinants of natural STLV-1 infection. We determined STLV-1 virus tropism in vivo and its relation to the immune response by evaluating cytokine production and T-cell subsets in naturally infected and uninfected mandrills. With real-time PCR methods, we found that STLV-1 in mandrills infects both CD4(+) and CD8(+) T cells; however, proviral loads were significantly higher (P = 0.01) in CD4(+) than in CD8(+) cells (mean STLV-1 copies number per 100 cells (+/- SD) was 7.8 +/- 8 in CD4(+) T cells and 3.9 +/- 4.5 in CD8(+) T cells). After culture, STLV-1 provirus was detected in enriched CD4(+) but not in enriched CD8(+) T cells. After 6 months of culture, STLV-1-transformed cell lines expressing CD3(+), CD4(+) and HLADR(+) were established, and STLV-1 proteins and tax/rex mRNA were detected. In STLV-1 infected monkeys, there was a correlation between high proviral load and elevated levels of interleukin (IL)-2, IL-6, IL-10, interferon-gamma and tumour necrosis factor-alpha. The two monkeys with the highest STLV-1 proviral load had activated CD4(+)HLADR(+) and CD8(+)HLADR(+) T-cell subsets and a high percentage of CD25(+) in CD4(+) and CD8(+) T cells. Our study provides the first cellular, immunological and virological characterization of natural STLV-1 infection in mandrills and shows that they are an appropriate animal model for further physiopathological studies of the natural history of human T-cell leukaemia viruses.

  4. The effect of HTLV-1 virulence factors (HBZ, Tax, proviral load), HLA class I and plasma neopterin on manifestation of HTLV-1 associated myelopathy tropical spastic paraparesis.

    Science.gov (United States)

    Tarokhian, Hanieh; Taghadosi, Mahdi; Rafatpanah, Hushang; Rajaei, Taraneh; Azarpazhooh, Mahmoud Reza; Valizadeh, Narges; Rezaee, S A Rahim

    2017-01-15

    Previous studies have suggested debatable roles of Tax and HBZ gene expression in the pathogenesis of HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). In this study, HTLV-1 and host interactions in the manifestation of HAM/TSP were evaluated. A cross-sectional study was conducted on 33 HAM/TSP patients and 38 HTLV-1 asymptomatic carriers (ACs). HTLV-1-Tax, HBZ gene expression, and proviral load (PVL) were assessed using the quantitative real-time PCR (TaqMan), host plasma neopterin level, and HLA-I, and the clinical manifestation were evaluated. The HTLV-1 PVLs in HAM/TSP and ACs were 306±360.741 copies/10(4) PBMCs and 250.98±629.94 copies/10(4) PBMCs, respectively; the PVL was higher in HAM/TSP than that in ACs (p=0.004). HTLV-1 Tax and HBZ expression in HAM/TSP was higher than that in ACs, wherein only the Tax expression was statistically significant (p=0.039). In contrast to Japanese HTLV-1-infected subjects, HLA-A*02, HLA-A*24, HLA-Cw*08, and HLA-B*5401 did not exhibit preventive effects for HAM/TSP manifestation. The plasma neopterin level was significantly higher in HAM/TSPs than that in ACs; furthermore, there was a strong significant correlation between plasma neopterin and PVL (R=0.76, p=0.001). Moreover, there were significant correlation between urinary disturbances and haematological indices, including the RBC count (R=-0.61, p=0.01) and Hematocrit (Ht) index (R=-0.75, p=0.002), and between mobility disturbances with Tax expression (R=-0.58, p=0.02) and WBC counts (R=-0.54, p=0.04), and finally, a significant association was found between the sensory disturbances and PVL (p=0.05). Overall, HTLV-1 PVL and Tax may be the valid predictors of disease development, and the neopterin level may be a valid predictor of disease progression. In addition, Tax and neopterin are more helpful than PVL for the monitoring of HTLV-1-infected patients. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. New entity, definition and diagnostic criteria of cutaneous adult T-cell leukemia/lymphoma: human T-lymphotropic virus type 1 proviral DNA load can distinguish between cutaneous and smoldering types.

    Science.gov (United States)

    Amano, Masahiro; Kurokawa, Motoki; Ogata, Katsumi; Itoh, Hiroshi; Kataoka, Hiroaki; Setoyama, Mitsuru

    2008-05-01

    Adult T-cell leukemia/lymphoma (ATLL) has been divided into four subtypes up to now: (i) acute; (ii) lymphoma; (iii) chronic; and (iv) smoldering. Skin lesion(s) may be present and the cases showing less than 5% abnormal T-lymphocytes in peripheral blood without involvement of other organs, have been classified as smoldering ATLL. However, this type of ATLL with skin manifestations had a worse prognosis than that without skin lesions. This study aimed to define and distinguish cutaneous ATLL lacking nodal lymphoma and leukemic change from smoldering ATLL. We propose an entity of cutaneous ATLL, which has less than 5% abnormal T lymphocyte in peripheral blood, a normal lymphocyte count (i.e. smoldering ATLL. HTLV-1 proviral loads, soluble interleukin-2 receptors and other parameters were examined in each case. HTLV-1 proviral DNA loads in smoldering ATLL group are significantly higher than those in asymptomatic carrier and cutaneous ATLL group. Cutaneous ATLL may be a distinct entity that should be separated from smoldering ATLL clinically and virologically.

  6. Estimation of bovine leukemia virus (BLV) proviral load harbored by lymphocyte subpopulations in BLV-infected cattle at the subclinical stage of enzootic bovine leucosis using BLV-CoCoMo-qPCR.

    Science.gov (United States)

    Panei, Carlos Javier; Takeshima, Shin-nosuke; Omori, Takashi; Nunoya, Tetsuo; Davis, William C; Ishizaki, Hiroshi; Matoba, Kazuhiro; Aida, Yoko

    2013-05-04

    Bovine leukemia virus (BLV) is associated with enzootic bovine leukosis (EBL), which is the most common neoplastic disease of cattle. BLV infection may remain clinically silent at the aleukemic (AL) stage, cause persistent lymphocytosis (PL), or, more rarely, B cell lymphoma. BLV has been identified in B cells, CD2+ T cells, CD3+ T cells, CD4+ T cells, CD8+ T cells, γ/δ T cells, monocytes, and granulocytes in infected cattle that do not have tumors, although the most consistently infected cell is the CD5+ B cell. The mechanism by which BLV causes uncontrolled CD5+ B cell proliferation is unknown. Recently, we developed a new quantitative real-time polymerase chain reaction (PCR) method, BLV-CoCoMo-qPCR, which enabled us to demonstrate that the proviral load correlates not only with BLV infection, as assessed by syncytium formation, but also with BLV disease progression. The present study reports the distribution of BLV provirus in peripheral blood mononuclear cell subpopulations isolated from BLV-infected cows at the subclinical stage of EBL as examined by cell sorting and BLV-CoCoMo-qPCR. Phenotypic characterization of five BLV-infected but clinically normal cattle with a proviral load of > 100 copies per 1 × 105 cells identified a high percentage of CD5+ IgM+ cells (but not CD5- IgM+ B cells, CD4+ T cells, or CD8+T cells). These lymphocyte subpopulations were purified from three out of five cattle by cell sorting or using magnetic beads, and the BLV proviral load was estimated using BLV-CoCoMo-qPCR. The CD5+ IgM+ B cell population in all animals harbored a higher BLV proviral load than the other cell populations. The copy number of proviruses infecting CD5- IgM+ B cells, CD4+ cells, and CD8+ T cells (per 1 ml of blood) was 1/34 to 1/4, 1/22 to 1/3, and 1/31 to 1/3, respectively, compared with that in CD5+ IgM+ B cells. Moreover, the BLV provirus remained integrated into the genomic DNA of CD5+ IgM+ B cells, CD5- IgM+ B cells, CD4+ T cells, and CD8+ T cells

  7. Human T-lymphotropic virus type 1 (HTLV-1 prevalence and quantitative detection of DNA proviral load in individuals with indeterminate/positive serological results

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    Bon Isabella

    2006-03-01

    Full Text Available Abstract Background HTLV-1 infection is currently restricted to endemic areas. To define the prevalence of HTLV-1 infection in patients living in Italy, we first carried out a retrospective serological analysis in a group of people originating from African countries referred to our hospital from January 2003 to February 2005. We subsequently applied a real time PCR on peripheral blood mononuclear cells from subjects with positive or indeterminate serological results. Methods All the sera were first analysed by serological methods (ELISA and/or Western Blotting and then the peripheral blood mononuclear cells from subjects with positive or inconclusive serological results were analyzed for the presence of proviral DNA by a sensitive SYBR Green real time PCR. In addition, twenty HTLV-I ELISA negative samples were assayed by real time PCR approach as negative controls. Results Serological results disclosed serum reactivity by ELISA (absorbance values equal or greater than the cut-off value in 9 out of 3408 individuals attending the Sexually Transmitted Diseases Clinic and/or Oncology Department, and 2 out 534 blood donors enrolled as a control population. Irrespective of positive or inconclusive serological results, all these subjects were analyzed for the presence of proviral DNA in peripheral blood mononuclear cells by SYBR real time PCR. A clear-cut positive result for the presence of HTLV-1 DNA was obtained in two subjects from endemic areas. Conclusion SYBR real time PCR cut short inconclusive serological results. This rapid and inexpensive assay showed an excellent linear dynamic range, specificity and reproducibility readily revealing and quantifying the presence of virus in PBMCs. Our results highlight the need to monitor the presence of HTLV-1 in countries which have seen a large influx of immigrants in recent years. Epidemiological surveillance and correct diagnosis are recommended to verify the prevalence and incidence of a new

  8. Cell-associated HIV DNA measured early during infection has prognostic value independent of serum HIV RNA measured concomitantly

    DEFF Research Database (Denmark)

    Katzenstein, Terese L; Oliveri, Roberto S; Benfield, Thomas

    2002-01-01

    Using data from the Danish AIDS Cohort of HIV-infected homosexual men established in the 1980s, the prognostic value of early HIV DNA loads was evaluated. In addition to DNA measurements, concomitant serum HIV RNA levels, CD4 cell counts and CCR5 genotypes were determined. The patients were divided...... of serum HIV RNA (p DNA, HIV RNA and CD4 cell counts were all included in a Cox model, only serum HIV RNA had independent prognostic value. Patients heterozygous for the CCR5 delta 32 allele had significantly lower HIV DNA loads than those homozygous for the normal allele (p ....05). The interplay between HIV RNA and DNA levels is discussed, together with the possibility that cell-associated HIV DNA load is a marker of the HIV RNA peak seen shortly after primary HIV infection....

  9. Cell-associated HIV DNA measured early during infection has prognostic value independent of serum HIV RNA measured concomitantly

    DEFF Research Database (Denmark)

    Katzenstein, Terese L; Oliveri, Roberto S; Benfield, Thomas

    2002-01-01

    Using data from the Danish AIDS Cohort of HIV-infected homosexual men established in the 1980s, the prognostic value of early HIV DNA loads was evaluated. In addition to DNA measurements, concomitant serum HIV RNA levels, CD4 cell counts and CCR5 genotypes were determined. The patients were divided...

  10. Damaging the Integrated HIV Proviral DNA with TALENs.

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    Christy L Strong

    Full Text Available HIV-1 integrates its proviral DNA genome into the host genome, presenting barriers for virus eradication. Several new gene-editing technologies have emerged that could potentially be used to damage integrated proviral DNA. In this study, we use transcription activator-like effector nucleases (TALENs to target a highly conserved sequence in the transactivation response element (TAR of the HIV-1 proviral DNA. We demonstrated that TALENs cleave a DNA template with the HIV-1 proviral target site in vitro. A GFP reporter, under control of HIV-1 TAR, was efficiently inactivated by mutations introduced by transfection of TALEN plasmids. When infected cells containing the full-length integrated HIV-1 proviral DNA were transfected with TALENs, the TAR region accumulated indels. When one of these mutants was tested, the mutated HIV-1 proviral DNA was incapable of producing detectable Gag expression. TALEN variants engineered for degenerate recognition of select nucleotide positions also cleaved proviral DNA in vitro and the full-length integrated proviral DNA genome in living cells. These results suggest a possible design strategy for the therapeutic considerations of incomplete target sequence conservation and acquired resistance mutations. We have established a new strategy for damaging integrated HIV proviral DNA that may have future potential for HIV-1 proviral DNA eradication.

  11. Construction of a High Titer Infectious HIV-1 Subtype C Proviral Clone from South Africa

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    Jochen Bodem

    2012-09-01

    Full Text Available The Human Immunodeficiency Virus type 1 (HIV-1 subtype C is currently the predominant subtype worldwide. Cell culture studies of Sub-Saharan African subtype C proviral plasmids are hampered by the low replication capacity of the resulting viruses, although viral loads in subtype C infected patients are as high as those from patients with subtype B. Here, we describe the sequencing and construction of a new HIV-1 subtype C proviral clone (pZAC, replicating more than one order of magnitude better than the previous subtype C plasmids. We identify the env-region for being the determinant for the higher viral titers and the pZAC Env to be M-tropic. This higher replication capacity does not lead to a higher cytotoxicity compared to previously described subtype C viruses. In addition, the pZAC Vpu is also shown to be able to down-regulate CD4, but fails to fully counteract CD317.

  12. The frequency of CD127low expressing CD4+CD25high T regulatory cells is inversely correlated with human T lymphotrophic virus type-1 (HTLV-1 proviral load in HTLV-1-infection and HTLV-1-associated myelopathy/tropical spastic paraparesis

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    Chieia Marco

    2008-07-01

    Full Text Available Abstract Background CD4+CD25high regulatory T (TReg cells modulate antigen-specific T cell responses, and can suppress anti-viral immunity. In HTLV-1 infection, a selective decrease in the function of TReg cell mediated HTLV-1-tax inhibition of FOXP3 expression has been described. The purpose of this study was to assess the frequency and phenotype of TReg cells in HTLV-1 asymptomatic carriers and in HTLV-1-associated neurological disease (HAM/TSP patients, and to correlate with measures of T cell activation. Results We were able to confirm that HTLV-I drives activation, spontaneous IFNγ production, and proliferation of CD4+ T cells. We also observed a significantly lower proportion of CTLA-4+ TReg cells (CD4+CD25high T cells in subjects with HAM/TSP patients compared to healthy controls. Ki-67 expression was negatively correlated to the frequency of CTLA-4+ TReg cells in HAM/TSP only, although Ki-67 expression was inversely correlated with the percentage of CD127low TReg cells in healthy control subjects. Finally, the proportion of CD127low TReg cells correlated inversely with HTLV-1 proviral load. Conclusion Taken together, the results suggest that TReg cells may be subverted in HAM/TSP patients, which could explain the marked cellular activation, spontaneous cytokine production, and proliferation of CD4+ T cells, in particular those expressing the CD25highCD127low phenotype. TReg cells represent a potential target for therapeutic intervention for patients with HTLV-1-related neurological diseases.

  13. HTLV-1 proviral integration sites differ between asymptomatic carriers and patients with HAM/TSP.

    Science.gov (United States)

    Niederer, Heather A; Laydon, Daniel J; Melamed, Anat; Elemans, Marjet; Asquith, Becca; Matsuoka, Masao; Bangham, Charles R M

    2014-09-30

    HTLV-1 causes proliferation of clonal populations of infected T cells in vivo, each clone defined by a unique proviral integration site in the host genome. The proviral load is strongly correlated with odds of the inflammatory disease HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). There is evidence that asymptomatic HTLV-1 carriers (ACs) have a more effective CD8 + T cell response, including a higher frequency of HLA class I alleles able to present peptides from a regulatory protein of HTLV-1, HBZ. We have previously shown that specific features of the host genome flanking the proviral integration site favour clone survival and spontaneous expression of the viral transactivator protein Tax in naturally infected PBMCs ex vivo. However, the previous studies were not designed or powered to detect differences in integration site characteristics between ACs and HAM/TSP patients. Here, we tested the hypothesis that the genomic environment of the provirus differs systematically between ACs and HAM/TSP patients, and between individuals with strong or weak HBZ presentation. We used our recently described high-throughput protocol to map and quantify integration sites in 95 HAM/TSP patients and 68 ACs from Kagoshima, Japan, and 75 ACs from Kumamoto, Japan. Individuals with 2 or more HLA class I alleles predicted to bind HBZ peptides were classified 'strong' HBZ binders; the remainder were classified 'weak binders'. The abundance of HTLV-1-infected T cell clones in vivo was correlated with proviral integration in genes and in areas with epigenetic marks associated with active regulatory elements. In clones of equivalent abundance, integration sites in genes and active regions were significantly more frequent in ACs than patients with HAM/TSP, irrespective of HBZ binding and proviral load. Integration sites in genes were also more frequent in strong HBZ binders than weak HBZ binders. Clonal abundance is correlated with integration in a

  14. HIV sequence diversity during the early phase of infection is associated with HIV DNA reductions during antiretroviral therapy.

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    Wang, Nidan; Li, Yijia; Han, Yang; Xie, Jing; Li, Taisheng

    2017-06-01

    The association between baseline human immunodeficiency virus (HIV) sequence diversity and HIV DNA decay after the initiation of antiretroviral therapy (ART) remains uncharacterized during the early stages of HIV infection. Samples were obtained from a cohort of 17 patients with early HIV infection (infection) who initiated ART, and the C2V5 region of the HIV-1 envelope (env) gene was amplified via single genome amplification (SGA) to determine the peripheral plasma HIV quasispecies. We categorized HIV quasispecies into two groups according to baseline viral sequence genetic distance, which was determined by the Poisson-Fitter tool. Total HIV DNA in peripheral blood mononuclear cells (PBMCs), viral load, and T cell subsets were measured prior to and after the initiation of ART. The median SGA sequence number was 17 (range 6-28). At baseline, we identified 7 patients with homogeneous viral populations (designated the Homogeneous group) and 10 patients with heterogeneous viral populations (designated the Heterogeneous group) based on SGA sequences. Both groups exhibited similar HIV DNA decay rates during the first 6 months of ART (P > 0.99), but the Homogenous group experienced more prominent decay than the Heterogeneous group after 6 months (P = 0.037). The Heterogeneous group had higher CD4 cell counts after ART initiation; however, both groups had comparable recovery in terms of CD4/CD8 ratios and CD8 T cell activation levels. Viral population homogeneity upon the initiation of ART is associated with a decrease in HIV DNA levels during ART. J. Med. Virol. 89:982-988, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  15. Peripheral blood mononuclear cells HIV DNA levels impact intermittently on neurocognition.

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    Lucette A Cysique

    Full Text Available To determine the contribution of peripheral blood mononuclear cells' (PBMCs HIV DNA levels to HIV-associated dementia (HAD and non-demented HIV-associated neurocognitive disorders (HAND in chronically HIV-infected adults with long-term viral suppression on combined antiretroviral treatment (cART.Eighty adults with chronic HIV infection on cART (>97% with plasma and CSF HIV RNA <50 copies/mL were enrolled into a prospective observational cohort and underwent assessments of neurocognition and pre-morbid cognitive ability at two visits 18 months apart. HIV DNA in PBMCs was measured by real-time PCR at the same time-points.At baseline, 46% had non-demented HAND; 7.5% had HAD. Neurocognitive decline occurred in 14% and was more likely in those with HAD (p<.03. Low pre-morbid cognitive ability was uniquely associated with HAD (p<.05. Log10 HIV DNA copies were stable between study visits (2.26 vs. 2.22 per 106 PBMC. Baseline HIV DNA levels were higher in those with lower pre-morbid cognitive ability (p<.04, and higher in those with no ART treatment during HIV infection 1st year (p = .03. Baseline HIV DNA was not associated with overall neurocognition. However, % ln HIV DNA change was associated with decline in semantic fluency in unadjusted and adjusted analyses (p = .01-.03, and motor-coordination (p = .02-.12 to a lesser extent.PBMC HIV DNA plays a role in HAD pathogenesis, and this is moderated by pre-morbid cognitive ability in the context of long-term viral suppression. While the HIV DNA levels in PBMC are not associated with current non-demented HAND, increasing HIV DNA levels were associated with a decline in neurocognitive functions associated with HAND progression.

  16. Peripheral Blood Mononuclear Cells HIV DNA Levels Impact Intermittently on Neurocognition

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    Cysique, Lucette A.; Hey-Cunningham, William J.; Dermody, Nadene; Chan, Phillip; Brew, Bruce J.; Koelsch, Kersten K.

    2015-01-01

    Objectives To determine the contribution of peripheral blood mononuclear cells’ (PBMCs) HIV DNA levels to HIV-associated dementia (HAD) and non-demented HIV-associated neurocognitive disorders (HAND) in chronically HIV-infected adults with long-term viral suppression on combined antiretroviral treatment (cART). Methods Eighty adults with chronic HIV infection on cART (>97% with plasma and CSF HIV RNA HIV DNA in PBMCs was measured by real-time PCR at the same time-points. Results At baseline, 46% had non-demented HAND; 7.5% had HAD. Neurocognitive decline occurred in 14% and was more likely in those with HAD (pHIV DNA copies were stable between study visits (2.26 vs. 2.22 per 106 PBMC). Baseline HIV DNA levels were higher in those with lower pre-morbid cognitive ability (pHIV infection 1st year (p = .03). Baseline HIV DNA was not associated with overall neurocognition. However, % ln HIV DNA change was associated with decline in semantic fluency in unadjusted and adjusted analyses (p = .01-.03), and motor-coordination (p = .02-.12) to a lesser extent. Conclusions PBMC HIV DNA plays a role in HAD pathogenesis, and this is moderated by pre-morbid cognitive ability in the context of long-term viral suppression. While the HIV DNA levels in PBMC are not associated with current non-demented HAND, increasing HIV DNA levels were associated with a decline in neurocognitive functions associated with HAND progression. PMID:25853424

  17. Using Resurrected Ancestral Proviral Proteins to Engineer Virus Resistance

    Directory of Open Access Journals (Sweden)

    Asunción Delgado

    2017-05-01

    Full Text Available Proviral factors are host proteins hijacked by viruses for processes essential for virus propagation such as cellular entry and replication. Pathogens and their hosts co-evolve. It follows that replacing a proviral factor with a functional ancestral form of the same protein could prevent viral propagation without fatally compromising organismal fitness. Here, we provide proof of concept of this notion. Thioredoxins serve as general oxidoreductases in all known cells. We report that several laboratory resurrections of Precambrian thioredoxins display substantial levels of functionality within Escherichia coli. Unlike E. coli thioredoxin, however, these ancestral thioredoxins are not efficiently recruited by the bacteriophage T7 for its replisome and therefore prevent phage propagation in E. coli. These results suggest an approach to the engineering of virus resistance. Diseases caused by viruses may have a devastating effect in agriculture. We discuss how the suggested approach could be applied to the engineering of plant virus resistance.

  18. Early antiretroviral therapy reduces HIV DNA following perinatal HIV infection.

    Science.gov (United States)

    Foster, Caroline; Pace, Matthew; Kaye, Steve; Hopkins, Emily; Jones, Mathew; Robinson, Nicola; Mant, Christine; Cason, John; Fidler, Sarah; Frater, John

    2017-08-24

    : The impact of antiretroviral therapy (ART) on the size of the HIV reservoir has implications for virological remission in adults, but is not well characterized in perinatally acquired infection. In a prospective observational study of 20 children with perinatally acquired infection and sustained viral suppression on ART for more than 5 years, proviral DNA was significantly higher in deferred (>4 years) versus early (first year of life) ART recipients (P = 0.0062), and correlated with age of initiation (P = 0.13; r = 0.57). No difference was seen in cell-associated viral RNA (P = 0.36). Identifying paediatric populations with smaller reservoirs may inform strategies with potential to induce ART-free remission.

  19. HIV DNA reservoir increases risk for cognitive disorders in cART-naïve patients.

    Directory of Open Access Journals (Sweden)

    Victor G Valcour

    Full Text Available Cognitive impairment remains frequent in HIV, despite combination antiretroviral therapy (cART. Leading theories implicate peripheral monocyte HIV DNA reservoirs as a mechanism for spread of the virus to the brain. These reservoirs remain present despite cART. The objective of this study was to determine if the level of HIV DNA in CD14(+ enriched monocytes predicted cognitive impairment and brain injury.We enrolled 61 cART-naïve HIV-infected Thais in a prospective study and measured HIV DNA in CD14(+ enriched monocyte samples in a blinded fashion. We determined HAND diagnoses by consensus panel and all participants underwent magnetic resonance spectroscopy (MRS to measure markers of brain injury. Immune activation was measured via cytokines in cerebrospinal fluid (CSF.The mean (SD age was 35 (6.9 years, CD4 T-lymphocyte count was 236 (139 and log10 plasma HIV RNA was 4.8 (0.73. Twenty-eight of 61 met HAND criteria. The log10 CD14(+ HIV DNA was associated with HAND in unadjusted and adjusted models (p = 0.001. There was a 14.5 increased odds ratio for HAND per 1 log-value of HIV DNA (10-fold increase in copy number. Plasma CD14(+ HIV DNA was associated with plasma and CSF neopterin (p = 0.023 and with MRS markers of neuronal injury (lower N-acetyl aspartate and glial dysfunction (higher myoinositol in multiple brain regions.Reservoir burden of HIV DNA in monocyte-enriched (CD14(+ peripheral blood cells increases risk for HAND in treatment-naïve HIV+ subjects and is directly associated with CSF immune activation and both brain injury and glial dysfunction by MRS.

  20. Using Resurrected Ancestral Proviral Proteins to Engineer Virus Resistance.

    Science.gov (United States)

    Delgado, Asunción; Arco, Rocio; Ibarra-Molero, Beatriz; Sanchez-Ruiz, Jose M

    2017-05-09

    Proviral factors are host proteins hijacked by viruses for processes essential for virus propagation such as cellular entry and replication. Pathogens and their hosts co-evolve. It follows that replacing a proviral factor with a functional ancestral form of the same protein could prevent viral propagation without fatally compromising organismal fitness. Here, we provide proof of concept of this notion. Thioredoxins serve as general oxidoreductases in all known cells. We report that several laboratory resurrections of Precambrian thioredoxins display substantial levels of functionality within Escherichia coli. Unlike E. coli thioredoxin, however, these ancestral thioredoxins are not efficiently recruited by the bacteriophage T7 for its replisome and therefore prevent phage propagation in E. coli. These results suggest an approach to the engineering of virus resistance. Diseases caused by viruses may have a devastating effect in agriculture. We discuss how the suggested approach could be applied to the engineering of plant virus resistance. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

  1. False-positive HIV DNA PCR testing of infants: implications in a changing epidemic.

    Science.gov (United States)

    Feucht, Ute Dagmar; Forsyth, Brian; Kruger, Mariana

    2012-02-23

    To examine false-positive HIV DNA polymerase chain reaction (PCR) test results in children, and the potential implications for the paediatric HIV epidemic in sub-Saharan Africa. A review was done of records over a 6-year period of children less than 18 months old at an HIV treatment site in South Africa, to evaluate those with an initial 'false'-positive HIV DNA PCR result, but later proven to be HIV-uninfected with HIV DNA PCR and/or quantitative HIV RNA PCR tests. We calculated the influence of changing HIV transmission rates on predictive values (PV) of HIV DNA PCR tests in a hypothetical population of all HIV-exposed infants over a 1-year period. (Positive PV: proportion of individuals with a positive test with disease; negative PV: proportion of individuals with negative test and no disease). Of 718 children, 40 with an initial positive HIV DNA PCR test were subsequently proven to be HIV-uninfected, resulting in a positive PV of 94.4%. Most (75%) uninfected children had PMTCT interventions and were asymptomatic or mildly symptomatic (77.5%). Calculations using a test specificity of 99.4%, as reported previously, show a decrease in positive PV using a single-test strategy from 98.6% at 30% HIV transmission rate, to 94.8% at 10% transmission, to 62.5% at 1% transmission. Reduction in test specificity further decreases positive PV at low transmission rates. Decreasing mother-to-child HIV transmission rates reduce the positive predictive value of a single HIV DNA PCR test result, necessitating adaptations to diagnostic algorithms to avoid misdiagnosis and inappropriate treatment, especially with early initiation of antiretroviral therapy in asymptomatic infants.

  2. HIV DNA and Dementia in Treatment-Naïve HIV-1-Infected Individuals in Bangkok, Thailand

    Science.gov (United States)

    Shiramizu, Bruce; Ratto-Kim, Silvia; Sithinamsuwan, Pasiri; Nidhinandana, Samart; Thitivichianlert, Sataporn; Watt, George; deSouza, Mark; Chuenchitra, Thippawan; Sukwit, Suchitra; Chitpatima, Suwicha; Robertson, Kevin; Paul, Robert; Shikuma, Cecilia; Valcour, Victor

    2007-01-01

    High HIV-1 DNA (HIV DNA) levels in peripheral blood mononuclear cells (PBMC) correlate with HIV-1-associated dementia (HAD) in patients on highly active antiretroviral therapy (HAART). If this relationship also exists among HAART-naïve patients, then HIV DNA may be implicated in the pathogenesis of HAD. In this study, we evaluated the relationship between HIV DNA and cognition in subjects naïve to HAART in a neuro AIDS cohort in Bangkok, Thailand. Subjects with and without HAD were recruited and matched for age, gender, education, and CD4 cell count. PBMC and cellular subsets were analyzed for HIV DNA using real-time PCR. The median log10 HIV DNA copies per 106 PBMC for subjects with HAD (n=15) was 4.27, which was higher than that found in subjects without dementia (ND; n=15), 2.28, p<0.001. This finding was unchanged in a multivariate model adjusting for plasma HIV-1 RNA levels. From a small subset of individuals, in which adequate number of cells were available, more HIV DNA was in monocytes/macrophages from those with HAD compared to those with ND. These results are consistent with a previous report among HAART-experienced subjects, thus further implicating HIV DNA in the pathogenesis of HAD. PMID:17211496

  3. Proviral Features of Human T Cell Leukemia Virus Type 1 in Carriers with Indeterminate Western Blot Analysis Results.

    Science.gov (United States)

    Kuramitsu, Madoka; Sekizuka, Tsuyoshi; Yamochi, Tadanori; Firouzi, Sanaz; Sato, Tomoo; Umeki, Kazumi; Sasaki, Daisuke; Hasegawa, Hiroo; Kubota, Ryuji; Sobata, Rieko; Matsumoto, Chieko; Kaneko, Noriaki; Momose, Haruka; Araki, Kumiko; Saito, Masumichi; Nosaka, Kisato; Utsunomiya, Atae; Koh, Ki-Ryang; Ogata, Masao; Uchimaru, Kaoru; Iwanaga, Masako; Sagara, Yasuko; Yamano, Yoshihisa; Okayama, Akihiko; Miura, Kiyonori; Satake, Masahiro; Saito, Shigeru; Itabashi, Kazuo; Yamaguchi, Kazunari; Kuroda, Makoto; Watanabe, Toshiki; Okuma, Kazu; Hamaguchi, Isao

    2017-09-01

    Western blotting (WB) for human T cell leukemia virus type 1 (HTLV-1) is performed to confirm anti-HTLV-1 antibodies detected at the initial screening of blood donors and in pregnant women. However, the frequent occurrence of indeterminate results is a problem with this test. We therefore assessed the cause of indeterminate WB results by analyzing HTLV-1 provirus genomic sequences. A quantitative PCR assay measuring HTLV-1 provirus in WB-indeterminate samples revealed that the median proviral load was approximately 100-fold lower than that of WB-positive samples (0.01 versus 0.71 copy/100 cells). Phylogenic analysis of the complete HTLV-1 genomes of WB-indeterminate samples did not identify any specific phylogenetic groups. When we analyzed the nucleotide changes in 19 HTLV-1 isolates from WB-indeterminate samples, we identified 135 single nucleotide substitutions, composed of four types, G to A (29%), C to T (19%), T to C (19%), and A to G (16%). In the most frequent G-to-A substitution, 64% occurred at GG dinucleotides, indicating that APOBEC3G is responsible for mutagenesis in WB-indeterminate samples. Moreover, interestingly, five WB-indeterminate isolates had nonsense mutations in Pol and/or Tax, Env, p12, and p30. These findings suggest that WB-indeterminate carriers have low production of viral antigens because of a combination of a low proviral load and mutations in the provirus, which may interfere with host recognition of HTLV-1 antigens. Copyright © 2017 American Society for Microbiology.

  4. Virological and immunological profiles among patients with undetectable viral load followed prospectively for 24 months

    DEFF Research Database (Denmark)

    Katzenstein, T L; Ullum, H; Røge, Birgit T

    2003-01-01

    OBJECTIVE: To quantify HIV-RNA in plasma, in lymphoid tissue and proviral DNA in peripheral blood mononuclear cells and to relate these to immunological markers among patients with plasma viral load counts of

  5. Quadratic recycling amplification for label-free and sensitive visual detection of HIV DNA.

    Science.gov (United States)

    Zhou, Wenjiao; Gong, Xue; Xiang, Yun; Yuan, Ruo; Chai, Yaqin

    2014-05-15

    Visual detections have attracted great research attentions recently due to their convenient monitoring of the target analytes without using any advanced instruments. However, achieving visual detection of trace amounts of biomolecules with PCR-like sensitivity remains a major challenge. In current work, we describe a new quadratic signal amplification strategy for sensitive visual detection of HIV DNA biomarkers based on exonuclease III (Exo III)-assisted DNA recycling amplification and DNAzymes. The presence of the target HIV DNA leads to two independent and simultaneous DNA recycling processes to achieve quadratic signal amplification with the assistance of Exo III. This quadratic signal amplification results in catalytic cleavage of the G-quadruplex sequence-locked hairpin probes to release numerous active G-quadruplex sequences, which further associate with hemin to form DNAzymes and cause significantly intensified color change for sensitive and visual detection of HIV DNA down to 2.5 pM. The proposed visual detection method employs un-modified hairpin DNA as probes, avoids using any complex and expensive instruments for signal transduction and is essentially simple. This method also shows single-base mismatch discrimination capability as well. All these features make our developed DNA detection method holds great potential for visual monitoring of various DNA biomarkers at ultralow levels with careful and proper probe designs. Copyright © 2013 Elsevier B.V. All rights reserved.

  6. Marcadores virológicos no convencionales en pacientes infectados con el virus de la inmunodeficiencia humana: ADN HIV-T, ADN HIV- 2LTR y ARN de HIV Non conventional virological markers in HIV-infected patients: T-HIV DNA, 2LTR-HIV DNA and HIV RNA

    Directory of Open Access Journals (Sweden)

    Rosana Gariglio

    2004-10-01

    study, we analyzed the presence of total HIV DNA (T-HIV DNA, non-integrated DNA with 2LTR (2LTR-HIV DNA and HIV RNA in a group of 55 HIV-positive subjects from Rosario City, with different clinical stages, with and without HAART. All markers were evaluated by PCR assays optimized in our laboratory that included colorimetric detection in microplate. HIV RNA clinical sensitivity was compared with a reference test, bDNA, resulting in 74% and 64% respectively, with an 85% of agreement. Thus, our HIV RNA assay could be used to monitor patients under HAART and at risk of infection. The 2LTR-HIV DNA was 54% positive although it was absent in patients with high VL. This marker was considered a labile product therefore its presence was associated with recent infection. However, current evidences question its stability. Thus, its clinical significance should be reconsidered. The absence of 2LTR-HIV DNA in patients with detectable VL may relate to the heterogeneity of the sequence used for its detection. T-HIV DNA was present in 100% of the samples and could be a relevant remission marker when therapies that effectively eradicate the infection became available.

  7. Multiple proviral integration events after virological synapse-mediated HIV-1 spread.

    Science.gov (United States)

    Russell, Rebecca A; Martin, Nicola; Mitar, Ivonne; Jones, Emma; Sattentau, Quentin J

    2013-08-15

    HIV-1 can move directly between T cells via virological synapses (VS). Although aspects of the molecular and cellular mechanisms underlying this mode of spread have been elucidated, the outcomes for infection of the target cell remain incompletely understood. We set out to determine whether HIV-1 transfer via VS results in productive, high-multiplicity HIV-1 infection. We found that HIV-1 cell-to-cell spread resulted in nuclear import of multiple proviruses into target cells as seen by fluorescence in-situ hybridization. Proviral integration into the target cell genome was significantly higher than that seen in a cell-free infection system, and consequent de novo viral DNA and RNA production in the target cell detected by quantitative PCR increased over time. Our data show efficient proviral integration across VS, implying the probability of multiple integration events in target cells that drive productive T cell infection. Copyright © 2013. Published by Elsevier Inc.

  8. Polo-like-kinase 1 is a proviral host-factor for hepatitis B virus replication

    Science.gov (United States)

    Diab, Ahmed M.; Foca, Adrien; Fusil, Floriane; Lahlali, Thomas; Jalaguier, Pascal; Amirache, Fouzia; N’Guyen, Lia; Isorce, Nathalie; Cosset, François-Loïc; Zoulim, Fabien; Andrisani, Ourania M; Durantel, David

    2017-01-01

    Chronic Hepatitis B Virus (HBV) infection is a major risk factor for hepatocellular carcinoma (HCC) and current treatments for CHB and HCC are perfectible. Herein, we identified cellular Serine/Threonine Polo-like-kinase 1 (PLK1) as a positive effector of HBV replication. The aim of this study was to demonstrate the proviral role of PLK1 in HBV biosynthesis and validate PLK1 inhibition a potential antiviral strategy. To this end, we employed physiologically relevant HBV infection models of Primary Human Hepatocytes (PHH) and differentiated HepaRG cells, in conjunction with pharmacologic PLK1 inhibitors, siRNA-mediated knockdown, and overexpression of constitutively active PLK1 (PLK1CA). In addition, humanized liver FRG mouse model was used to determine antiviral effect of PLK1 inhibitor BI-2536 on HBV infection in vivo. Lastly, in vitro PLK1 kinase assays and site-directed mutagenesis were employed to demonstrate HBV core protein (HBc) is a PLK1 substrate. We demonstrate HBV infection activated cellular PLK1 in PHH and dHepaRG cells. PLK1 inhibition by BI-2536 or siRNA-mediated knockdown suppressed, whereas overexpression of PLK1CA increased HBV DNA biosynthesis, supporting PLK1 effects on viral biosynthesis are specific, and PLK1 is a proviral cellular factor. Significantly, BI-2536 administration to HBV-infected humanized liver FRG mice strongly inhibited HBV infection, validating PLK1 as a novel antiviral target in vivo. The proviral action of PLK1 is associated with the biogenesis of the nucleocapsid, as BI-2536 leads to its decreased intracellular formation/accumulation. In this respect, our studies identified HBc as a PLK1 substrate in vitro, and mapped PLK1 phosphorylation sites on this protein. PLK1 is a proviral host factor that could be envisaged as a target for combined antiviral and antitumoral strategies against HBV infection and HBV mediated carcinogenesis. PMID:28445592

  9. HIV drug resistance mutations in proviral DNA from a community treatment program.

    Directory of Open Access Journals (Sweden)

    Anne Derache

    Full Text Available Drug resistance mutations archived in resting memory CD4+ cells may persist despite suppression of HIV RNA to <50 copies/ml. We sequenced pol gene from proviral DNA among viremic and suppressed patients to identify drug resistance mutations.The Peninsula AIDS Research Cohort study enrolled and followed over 2 years 120 HIV infected patients from San Mateo and San Francisco Counties. HIV-1 pol genotyping by bulk sequencing was performed on 38 DNA and RNA from viremic patients and DNA only among 82 suppressed patients at baseline. Antiretroviral susceptibility was predicted by HIVDB.stanford.edu.Among 120 subjects, 81% were on antiretroviral therapy and had been treated for a median time of 7 years. Thirty-two viremic patients showed concordant RNA and DNA genotypes (84%; the discordant profiles were mainly observed in patients with low-level viremia. Among suppressed patients, 21 had drug resistance mutations in proviral DNA (26% with potential resistance to one, two or three ARV classes in 16, 4 and 1 samples respectively.The high level of genotype concordance between DNA and RNA in viremic patients suggested that DNA genotyping might be used to assess drug resistance in resource-limited settings, and further investigation of extracted DNA from dried blood spots is needed. Drug resistance mutations in proviral DNA in 26% of subjects with less than 50 copies/ml pose a risk for the transmission of drug resistant virus with virologic failure, treatment interruption or decreased adherence.

  10. Distinctive Drug-resistant Mutation Profiles and Interpretations of HIV-1 Proviral DNA Revealed by Deep Sequencing in Reverse Transcriptase.

    Science.gov (United States)

    Yin, Qian Qian; Li, Zhen Peng; Zhao, Hai; Pan, Dong; Wang, Yan; Xu, Wei Si; Xing, Hui; Feng, Yi; Jiang, Shi Bo; Shao, Yi Ming; Ma, Li Ying

    2016-04-01

    To investigate distinctive features in drug-resistant mutations (DRMs) and interpretations for reverse transcriptase inhibitors (RTIs) between proviral DNA and paired viral RNA in HIV-1-infected patients. Forty-three HIV-1-infected individuals receiving first-line antiretroviral therapy were recruited to participate in a multicenter AIDS Cohort Study in Anhui and Henan Provinces in China in 2004. Drug resistance genotyping was performed by bulk sequencing and deep sequencing on the plasma and whole blood of 77 samples, respectively. Drug-resistance interpretation was compared between viral RNA and paired proviral DNA. Compared with bulk sequencing, deep sequencing could detect more DRMs and samples with DRMs in both viral RNA and proviral DNA. The mutations M184I and M230I were more prevalent in proviral DNA than in viral RNA (Fisher's exact test, PDNA, and 5 of these samples with different DRMs between proviral DNA and paired viral RNA showed a higher level of drug resistance to the first-line drugs. Considering 'minority resistant variants', 22 samples (28.57%) were associated with a higher level of drug resistance to the tested RTIs for proviral DNA when compared with paired viral RNA. Compared with viral RNA, the distinctive information of DRMs and drug resistance interpretations for proviral DNA could be obtained by deep sequencing, which could provide more detailed and precise information for drug resistance monitoring and the rational design of optimal antiretroviral therapy regimens. Copyright © 2016 The Editorial Board of Biomedical and Environmental Sciences. Published by China CDC. All rights reserved.

  11. Genome organization of the Chelonus inanitus polydnavirus: excision sites, spacers and abundance of proviral and excised segments.

    Science.gov (United States)

    Annaheim, Marc; Lanzrein, Beatrice

    2007-02-01

    Polydnaviruses are only found in symbiotic association with parasitic wasps within the families Ichneumonidae and Braconidae (ichnoviruses and bracoviruses). They have a segmented genome consisting of circular double-stranded DNA. In the proviral linear form they are integrated in the wasp's genome; in two bracoviruses, segments were found to be clustered. Proviral segments have direct terminal repeats. Segment excision has been proposed to occur through juxtaposition of these repeats by formation of a loop and recombination; one copy of the repeat then ends up in the circular segment and one in the rejoined DNA. Here we analysed the excision/circularization site of four segments of the Chelonus inanitus bracovirus (CiV) and found that they are similar to the two already known sites; on the basis of the combined data an extended excision site motif was found. Analyses of segment flanking sequences led to the first identification of one complete and several partial spacers between proviral segments in a polydnavirus. The spacer between the proviral segments CiV14 and CiV22.5 has a length of 2065 bp; the terminal repeats of CiV14 and CiV22.5 were seen to have an opposite orientation and from this a model on the spacial organization of the loops of the proviral cluster is proposed. Through various approaches it was shown that spacers are not excised or injected into the host. Measurement of relative abundances of various segments in proviral and excised form indicates for the first time that abundant segments are present in multiple copies in the proviral form.

  12. Polo-like-kinase 1 is a proviral host factor for hepatitis B virus replication.

    Science.gov (United States)

    Diab, Ahmed; Foca, Adrien; Fusil, Floriane; Lahlali, Thomas; Jalaguier, Pascal; Amirache, Fouzia; N'Guyen, Lia; Isorce, Nathalie; Cosset, François-Loïc; Zoulim, Fabien; Andrisani, Ourania; Durantel, David

    2017-12-01

    Chronic hepatitis B virus (HBV) infection is a major risk factor for hepatocellular carcinoma (HCC) and current treatments for chronic hepatitis B and HCC are suboptimal. Herein, we identified cellular serine/threonine Polo-like-kinase 1 (PLK1) as a positive effector of HBV replication. The aim of this study was to demonstrate the proviral role of PLK1 in HBV biosynthesis and validate PLK1 inhibition a potential antiviral strategy. To this end, we employed physiologically relevant HBV infection models of primary human hepatocytes (PHHs) and differentiated HepaRG cells in conjunction with pharmacologic PLK1 inhibitors, small interfering RNA (siRNA)-mediated knockdown, and overexpression of constitutively active PLK1 (PLK1CA ). In addition, a humanized liver Fah-/- /Rag2-/- /Il2rg-/- (FRG) mouse model was used to determine the antiviral effect of PLK1 inhibitor BI-2536 on HBV infection in vivo. Finally, in vitro PLK1 kinase assays and site-directed mutagenesis were employed to demonstrate that HBV core protein (HBc) is a PLK1 substrate. We demonstrated that HBV infection activated cellular PLK1 in PHHs and differentiated HepaRG cells. PLK1 inhibition by BI-2536 or siRNA-mediated knockdown suppressed HBV DNA biosynthesis, whereas overexpression of PLK1CA increased it, suggesting that the PLK1 effects on viral biosynthesis are specific and that PLK1 is a proviral cellular factor. Significantly, BI-2536 administration to HBV-infected humanized liver FRG mice strongly inhibited HBV infection, validating PLK1 as an antiviral target in vivo. The proviral action of PLK1 is associated with the biogenesis of the nucleocapsid, as BI-2536 leads to its decreased intracellular formation/accumulation. In this respect, our studies identified HBc as a PLK1 substrate in vitro, and mapped PLK1 phosphorylation sites on this protein. PLK1 is a proviral host factor that could be envisaged as a target for combined antiviral and antitumoral strategies against HBV infection and HBV

  13. Investigating signs of recent evolution in the pool of proviral HIV type 1 DNA during years of successful HAART

    DEFF Research Database (Denmark)

    Mens, Helene; Pedersen, Anders G; Jørgensen, Louise B

    2007-01-01

    In order to shed light on the nature of the persistent reservoir of human immunodeficiency virus type 1 (HIV-1), we investigated signs of recent evolution in the pool of proviral DNA in patients on successful HAART. Pro-viral DNA, corresponding to the C2-V3-C3 region of the HIV-1 env gene......, was collected from PBMCs isolated from 57 patients. Both "consensus" (57 patients) and clonal (7 patients) sequences were obtained from five time points spanning a 24-month period. The main computational strategy was to use maximum likelihood to fit a set of alternative phylogenetic models to the clonal data...

  14. Investigating signs of recent evolution in the pool of proviral HIV type 1 DNA during years of successful HAART

    DEFF Research Database (Denmark)

    Mens, Helene; Pedersen, Anders G; Jørgensen, Louise B

    2007-01-01

    In order to shed light on the nature of the persistent reservoir of human immunodeficiency virus type 1 (HIV-1), we investigated signs of recent evolution in the pool of proviral DNA in patients on successful HAART. Pro-viral DNA, corresponding to the C2-V3-C3 region of the HIV-1 env gene...... HIV genomes in some patients. Interestingly, stop-codons were present at the same two positions in several independent clones and across patients. Simulation studies indicated that this phenomenon could be explained as the result of parallel evolution and that some sites were inherently more likely...

  15. HIV DNA and antibodies in syringes from injecting drug users: a comparison of detection techniques.

    Science.gov (United States)

    Myers, S S; Heimer, R; Liu, D; Henrard, D

    1993-07-01

    Direct HIV testing of individual injecting drug users is not always feasible. As an alternative, we have evaluated the sensitivity and specificity of several techniques for detecting HIV-1-specific products in used syringes. Polymerase chain reaction (PCR) and antibody-capture assays were compared using syringes prepared with blood from HIV-1-positive and -negative individuals. PCR sensitivity was maximized, enabling detection of single copies of HIV-1-specific proviral DNA. The limits of detection from used syringes were determined for PCR by diluting extracts and correlated to CD4+ cell counts. Similarly, limits of detection were determined for enzyme immunoassays (EIA) and Western blot. All techniques were highly specific, although with PCR false-positives were detected occasionally. EIA proved more sensitive than Western blot in detecting needles containing HIV-1-infected individuals' blood. Even after prolonged storage of syringes at room temperature, EIA was equal to or better than PCR as an HIV-1 detection technique. The most sensitive method for detecting HIV-1 was the viral-based EIA when the recommended predilution step was omitted. EIA proved preferable to PCR because of their higher sensitivity, absence of false-positives and easier sample preparation and analysis.

  16. False-negative post-18-month confirmatory HIV tests in HIV DNA PCR-positive children: a retrospective analysis.

    Science.gov (United States)

    Garcia-Prats, Anthony J; Draper, Heather R; Sanders, Jill E; Agrawal, Anurag K; Mohapi, Edith Q; Schutze, Gordon E

    2012-09-24

    The WHO guidelines for children less than 18 months old diagnosed with HIV based on presumptive clinical diagnosis or one virologic test recommend confirmatory HIV antibody testing after 18 months of age. This study describes post-18-month HIV test results following this WHO-recommended confirmatory testing strategy. Case series and retrospective review of routine program data. Children enrolled at the Baylor Children's Clinical Center of Excellence, a pediatric and family HIV clinic in Maseru, Lesotho from December 2005 through January 2009 with a positive HIV DNA PCR at less than 18 months of age and HIV rapid test results after 18 months of age were included. Post-18-month confirmatory HIV test results are described. Factors associated with non-positive confirmatory rapid tests were determined using binary logistic regression. Of the 109 children meeting inclusion criteria, 22 (20.2%) had negative and 27 (24.8%) discordant confirmatory rapid tests. Forty-six of these 49 were on antiretroviral therapy (ART). Among these 49, 11 of 24 post-18-month HIV DNA PCRs were negative, whereas nine of 10 post-18-month HIV ELISAs were positive; 29 were definitively and 17 probably HIV-infected, two were uninfected, and one had undetermined status. Only age less than 9 months at ART initiation (odds ratio 4.25, P = 0.002) was associated with non-positive rapid tests. False-negative post-18-month confirmatory rapid tests and HIV DNA PCRs in children on ART are common, associated with early ART initiation, and may lead to inappropriate ART discontinuation and discharge from care of truly HIV-infected children.

  17. Investigation of the bovine leukemia virus proviral DNA in human leukemias and lung cancers in Korea.

    Science.gov (United States)

    Lee, Jehoon; Kim, Yonggoo; Kang, Chang Suk; Cho, Dae Hyun; Shin, Dong Hwan; Yum, Young Na; Oh, Jae Ho; Kim, Sheen Hee; Hwang, Myung Sil; Lim, Chul Joo; Yang, Ki Hwa; Han, Kyungja

    2005-08-01

    The bovine leukemia virus (BLV) is the causative agent of enzootic bovine leucosis. This study investigated the presence of the BLV in leukemia (179 acute lymphoblastic leukemia, 292 acute myeloid leukemia and 46 chronic myelogenous leukemia cases) and 162 lung cancer patients (139 adenocarcinoma, 23 squamous cell carcinoma) to determine if the BLV is a causative organism of leukemia and lung cancer in Koreans. A BLV infection was confirmed in human cells by PCR using a BLV-8 primer combination. All 517 cases of human leukemia and 162 lung cancer were negative for a PCR of the BLV proviral DNA. In conclusion, although meat has been imported from BLV endemic areas, the BLV infection does not appear to be the cause of human leukemia or lung cancer in Koreans. These results can be used as a control for further studies on the BLV in Koreans.

  18. Existence of proviral porcine endogenous retrovirus in fresh and decellularised porcine tissues

    Directory of Open Access Journals (Sweden)

    Prabha S

    2008-01-01

    Full Text Available Purpose: Swine are expected to be utilized as xenograft donors for both whole organ and cellular transplantation. A major concern in using porcine organs for transplantation is the potential of transmission of porcine endogenous retrovirus (PERV. Tissue-engineered or decellularised heart valves have already been implanted in humans and have been marketed by certain companies after Food and Drug Administration (FDA approval. The aim of this study was to examine the existence of porcine endogenous retrovirus (PERV in fresh and decellularised porcine tissues. Methods: Porcine tissues (both fresh and decellularised were analysed using validated assays specific for PERV: polymerase chain reaction (PCR, reverse transcriptase polymerase chain reaction (RT-PCR. Results: PERV specific GAG sequences were found in the porcine heart tissue samples using PCR for DNA and RT- PCR for RNA. All tissue samples (both fresh and treated tissues like aortic valve, pulmonary valve and heart muscle showed the presence of PERV DNA. RT PCR for PERV was positive in all fresh tissues and was found to be negative in decellularised treated tissues. Conclusions: PCR is a rapid, specific test for the detection of PERV virus in xenografts. These findings have demonstrated that the presence of proviral DNA form of PERV in porcine tissues needs to be carefully considered when the infectious disease potential of xenotransplantation is being assessed.

  19. CD4+ and CD8+ T cell activation are associated with HIV DNA in resting CD4+ T cells.

    Directory of Open Access Journals (Sweden)

    Leslie R Cockerham

    Full Text Available The association between the host immune environment and the size of the HIV reservoir during effective antiretroviral therapy is not clear. Progress has also been limited by the lack of a well-accepted assay for quantifying HIV during therapy. We examined the association between multiple measurements of HIV and T cell activation (as defined by markers including CD38, HLA-DR, CCR5 and PD-1 in 30 antiretroviral-treated HIV-infected adults. We found a consistent association between the frequency of CD4+ and CD8+ T cells expressing HLA-DR and the frequency of resting CD4+ T cells containing HIV DNA. This study highlights the need to further examine this relationship and to better characterize the biology of markers commonly used in HIV studies. These results may also have implications for reactivation strategies.

  20. Cloning the human betaretrovirus proviral genome from patients with primary biliary cirrhosis.

    Science.gov (United States)

    Xu, Lizhe; Sakalian, Michael; Shen, Zhiwei; Loss, George; Neuberger, James; Mason, Andrew

    2004-01-01

    Patients with primary biliary cirrhosis (PBC) have both serologic and tissue evidence of infection. A recently identified human betaretrovirus was originally cloned from the biliary epithelium cDNA library of a patient with PBC. By conducting a BLASTN search, the initial partial pol gene fragment was found to have 95% to 97% nucleotide homology with mouse mammary tumor virus (MMTV) and with retrovirus sequences derived from human breast cancer samples. Using an anti-p27(CA) MMTV antibody, viral proteins were detected in the perihepatic lymph nodes but not in liver tissue samples from patients with PBC, suggesting a higher viral burden in lymphoid tissue. Therefore, in the current study, we used lymph node DNA to clone the proviral genome of the human betaretrovirus from two patients with PBC using a polymerase chain reaction (PCR) walking methodology with conserved primers complementary to MMTV. The human betaretrovirus genome contains five potential open reading frames (ORF) for Gag, protease (Pro), polymerase (Pol), envelope (Env), and superantigen (Sag) proteins that are collinear with their counterparts in MMTV. Alignment studies performed with characterized MMTV and human breast cancer betaretrovirus amino acid sequences revealed a 93% to 99% identity with the p27 capsid proteins, a 93% to 97% identity with the betaretrovirus envelope proteins, and a 76% to 85% identity with the more variable superantigen proteins. Phylogenetic analysis of known betaretrovirus superantigen proteins showed that the human and murine sequences did not cluster as two distinct species. In conclusion, human betaretrovirus nucleic acid sequences have been cloned from patients with PBC. They share marked homology with MMTV and human breast cancer-derived retrovirus sequences.

  1. Genome-wide amplification of proviral sequences reveals new polymorphic HERV-K(HML-2) proviruses in humans and chimpanzees that are absent from genome assemblies.

    Science.gov (United States)

    Macfarlane, Catriona M; Badge, Richard M

    2015-04-28

    To date, the human population census of proviruses of the Betaretrovirus-like human endogenous retroviral (HERV-K) (HML-2) family has been compiled from a limited number of complete genomes, making it certain that rare polymorphic loci are under-represented and are yet to be described. Here we describe a suppression PCR-based method called genome-wide amplification of proviral sequences (GAPS) that selectively amplifies DNA fragments containing the termini of HERV-K(HML-2) proviral sequences and their flanking genomic sequences. We analysed the HERV-K(HML-2) proviral content of 101 unrelated humans, 4 common chimpanzees and three centre d'etude du polymorphisme humain (CEPH) pedigrees (44 individuals). The technique isolated HERV-K(HML-2) proviruses that had integrated in the genomes of the great apes throughout their divergence and included evolutionarily young elements still unfixed for presence/absence. By examining the HERV-K(HML-2) proviral content of 145 humans we detected a new insertionally polymorphic Type I HERV-K(HML-2) provirus. We also observed provirus versus solo long terminal repeat (LTR) polymorphism within humans at a previously unreported, but ancient, locus. Finally, we report two novel chimpanzee specific proviruses, one of which is dimorphic for a provirus versus solo LTR. Thus GAPS enables the isolation of uncharacterised HERV-K(HML-2) proviral sequences and provides a direct means to assess inter-individual genetic variation associated with HERV-K(HML-2) proviruses.

  2. Design and implementation of an external quality assessment program for HIV viral load measurements using dried blood spots.

    Science.gov (United States)

    Prach, Lisa M; Puren, Adrian; Lippman, Sheri A; Carmona, Sergio; Stephenson, Sophie; Cutler, Ewalde; Barnhart, Scott; Liegler, Teri

    2015-03-01

    An external quality assurance program was developed for HIV-1 RNA viral load measurements taken from dried blood spots using a reference panel and field-collected specimens. The program demonstrated that accurate and reproducible quantitation can be obtained from field-collected specimens. Residual proviral DNA may confound interpretation in virologically suppressed subjects. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  3. Identification of full-length proviral DNA of porcine endogenous retrovirus from Chinese Wuzhishan miniature pigs inbred.

    Science.gov (United States)

    Ma, Yuyuan; Lv, Maomin; Xu, Shu; Wu, Jianmin; Tian, Kegong; Zhang, Jingang

    2010-07-01

    Existence of porcine endogenous retrovirus (PERV) hinders pigs to be used in clinical xenotransplantation to alleviate the shortage of human transplants. Chinese miniature pigs are potential organ donors for xenotransplantation in China. However, so far, an adequate level of information on the molecular characteristics of PERV from Chinese miniature pigs has not been available. We described here the cloning and characterization of full-length proviral DNA of PERV from Chinese Wuzhishan miniature pigs inbred (WZSP). Full-length nucleotide sequences of PERV-WZSP and other PERVs were aligned and phylogenetic tree was constructed from deduced amino-acid sequences of env. The results demonstrated that the full-length proviral DNA of PERV-WZSP belongs to gammaretrovirus and shares high similarity with other PERVs. Sequence analysis also suggested that different patterns of LTR existed in the same porcine germ line and partial PERV-C sequence may recombine with PERV-A sequence in LTR. (c) 2008 Elsevier Ltd. All rights reserved.

  4. Diverse wild mouse origins of xenotropic, mink cell focus-forming, and two types of ecotropic proviral genes.

    Science.gov (United States)

    Kozak, C A; O'Neill, R R

    1987-10-01

    We analyzed wild mouse DNAs for the number and type of proviral genes related to the env sequences of various murine leukemia viruses (MuLVs). Only Mus species closely related to laboratory mice carried these retroviral sequences, and the different subclasses of viral env genes tended to be restricted to specific taxonomic groups. Only Mus musculus molossinus carried proviral genes which cross-reacted with the inbred mouse ecotropic MuLV env gene. The ecotropic viral env sequence associated with the Fv-4 resistance gene was found in the Asian mice M. musculus molossinus and Mus musculus castaneus and in California mice from Lake Casitas (LC). Both M. musculus castaneus and LC mice carried many additional Fv-4 env-related proviruses, two of which are common to both mouse populations, which suggests that these mice share a recent common ancestry. Xenotropic and mink cell focus-forming (MCF) virus env sequences were more widely dispersed in wild mice than the ecotropic viral env genes, which suggests that nonecotropic MuLVs were integrated into the Mus germ line at an earlier date. Xenotropic MuLVs represented the major component of MuLV env-reactive genes in Asian and eastern European mice classified as M. musculus molossinus, M. musculus castaneus, and Mus musculus musculus, whereas Mus musculus domesticus from western Europe, the Mediterranean, and North America contained almost exclusively MCF virus env copies. M. musculus musculus mice from central Europe trapped near the M. musculus domesticus/M. musculus musculus hybrid zone carried multiple copies of both types of env genes. LC mice also carried both xenotropic and MCF viral env genes, which is consistent with the above conclusion that they represent natural hybrids of M. musculus domesticus and M. musculus castaneus.

  5. Evolution of specific antibodies and proviral DNA in milk of small ruminants infected by small ruminant lentivirus.

    Science.gov (United States)

    Barquero, Nuria; Gomez-Lucia, Esperanza; Arjona, Alvaro; Toural, Cristina; Heras, Alfonso las; Fernández-Garayzabal, José F; Domenech, Ana

    2013-10-22

    The diagnosis of Small Ruminant Lentivirus (SRLV) is based on clinical signs, pathological lesions and laboratory testing. No standard reference test for the diagnosis of maedi visna has been validated up to the present, and it is puzzling that tests which detect antibodies against the virus and tests which detect the proviral genome may render opposite results. The aim of this study was to evaluate the presence in milk throughout a lactation period of specific antibodies by ELISA and of SRLV proviral DNA by a PCR of the highly conserved pol region. A six-month study was conducted with the milk of 28 ewes and 31 goats intensively reared. The percentage of animals with antibodies against SRLV increased throughout the study period. Seroprevalence in sheep was 28% at the beginning of the study and by the end it had increased up to 52.4%. In goats, initial seroprevalence of 5.6% increased to 16%. The percentage of PCR positive ewes was stable throughout the study period. Of the positive sheep, 21.4% were PCR-positive before antibodies could be detected and most of them became PCR-negative shortly after the first detection of antibodies. This might suggest that antibodies have a neutralizing effect. In addition, an equal percentage of sheep were always PCR-negative but either became ELISA-positive or was always ELISA-positive, which might support this hypothesis. On the other hand, the PCR results in goats did not follow any pattern and oscillated between 35.3% and 55.6% depending on the month. Most goats positive by PCR failed to develop antibodies in the 6 months tested. We may conclude that the infection and the antibody response to it follow a different trend in sheep and goats.

  6. DNA-stabilized silver nanoclusters and carbon nanoparticles oxide: A sensitive platform for label-free fluorescence turn-on detection of HIV-DNA sequences.

    Science.gov (United States)

    Ye, Yu-Dan; Xia, Li; Xu, Dang-Dang; Xing, Xiao-Jing; Pang, Dai-Wen; Tang, Hong-Wu

    2016-11-15

    Based on the remarkable difference between the interactions of carbon nanoparticles (CNPs) oxide with single-stranded DNA (ssDNA) and double-stranded DNA (dsDNA), and the fact that fluorescence of DNA-stabilized silver nanoclusters (AgNCs) can be quenched by CNPs oxide, DNA-functionalized AgNCs were applied as label-free fluorescence probes and a novel fluorescence resonance energy transfer (FRET) sensor was successfully constructed for the detection of human immunodeficiency virus (HIV) DNA sequences. CNPs oxide were prepared with the oxidation of candle soot, hence it is simple, time-saving and low-cost. The strategy of dual AgNCs probes was applied to improve the detection sensitivity by using dual- probe capturing the same target DNA in a sandwich mode and as the fluorescence donor, and using CNPs oxide as the acceptor. In the presence of target DNA, a dsDNA hybrid forms, leading to the desorption of the ssDNA-AgNCs probes from CNPs oxide, and the recovering of fluorescence of the AgNCs in a HIV-DNA concentration-dependent manner. The results show that HIV-DNA can be detected in the range of 1-50nM with a detection limit of 0.40nM in aqueous buffer. The method is simple, rapid and sensitive with no need of labeled fluorescent probes, and moreover, the design of fluorescent dual-probe makes full use of the excellent fluorescence property of AgNCs and further improves the detection sensitivity. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. CD4 cell count and HIV DNA level are independent predictors of disease progression after primary HIV type 1 infection in untreated patients.

    Science.gov (United States)

    Goujard, Cécile; Bonarek, Mojgan; Meyer, Laurence; Bonnet, Fabrice; Chaix, Marie-Laure; Deveau, Christiane; Sinet, Martine; Galimand, Julie; Delfraissy, Jean-François; Venet, Alain; Rouzioux, Christine; Morlat, Philippe

    2006-03-01

    Treatment initiation at the time of primary human immunodeficiency virus (HIV) type 1 (HIV-1) infection has become less frequent in recent years. In the French prospective PRIMO Cohort, in which patients are enrolled at the time of primary HIV-1 infection, 30% of the 552 patients recruited during 1996-2004 did not start receiving antiretroviral treatment during the first 3 months after diagnosis. We analyzed the patients' clinical and immunological outcomes and examined potential predictors of disease progression. Progression was defined as the occurrence of an acquired immunodeficiency syndrome (AIDS)-related clinical event or a CD4 cell count <350 cells/mm3. Fifty-six (34%) of the untreated patients experienced immunological progression during a median duration of follow-up of 24 months, and 1 of these patients had an AIDS-related event. The estimated risks of progression were 25%, 34%, and 42% at 1, 2, and 3 years after enrollment, respectively. Compared with patients who did not have progression, those with progression had significantly lower CD4 cell counts at diagnosis (455 vs. 738 cells/mm3), higher plasma HIV RNA levels (4.9 vs. 4.5 log10 copies/mL), and higher HIV DNA levels (3.3 vs. 3.0 log(10) copies/10(6) peripheral blood mononuclear cells [PBMCs]). All 3 parameters were significantly associated with progression in univariate analysis. In multivariate analysis, only the CD4 cell count and HIV DNA level were independently predictive of disease progression (relative hazard for CD4 cell count, 1.84 per decrease of 100 cells/mm3; relative hazard for HIV DNA level, 2.73 per increase of 1 log(10) copies/10(6) PBMCs). Both a low initial CD4 cell count and a high HIV DNA level are predictive of rapid progression of untreated primary HIV-1 infection. Affected patients may therefore benefit from close clinical and laboratory monitoring and/or early administration of treatment.

  8. Genotypic tropism testing in proviral DNA to guide maraviroc initiation in aviremic subjects: 48-week analysis of the PROTEST study.

    Science.gov (United States)

    Garcia, Federico; Poveda, Eva; Pérez-Elías, Maria Jesús; Quero, José Hernández; Ribas, Maria Angels; Martínez-Madrid, Onofre J; Flores, Juan; Crespo, Manel; Gutiérrez, Félix; García-Deltoro, Miguel; Imaz, Arkaitz; Ocampo, Antonio; Artero, Arturo; Blanco, Francisco; Bernal, Enrique; Pasquau, Juan; Mínguez-Gallego, Carlos; Pérez, Núria; Aiestarán, Aintzane; Paredes, Roger

    2014-01-01

    In a previous interim 24-week virological safety analysis of the PROTEST study (1), initiation of Maraviroc (MVC) plus 2 nucleoside reverse-transcriptase inhibitors (NRTIs) in aviremic subjects based on genotypic tropism testing of proviral HIV-1 DNA was associated with low rates of virological failure. Here we present the final 48-week analysis of the study. PROTEST was a phase 4, prospective, single-arm clinical trial (ID: NCT01378910) carried on in 24 HIV care centres in Spain. Maraviroc-naïve HIV-1-positive adults with HIV-1 RNA (VL) 10% in a singleton), initiated MVC with 2 NRTIs and were followed for 48 weeks. Virological failure was defined as two consecutive VL>50 c/mL. Recent adherence was calculated as: (# pills taken/# pills prescribed during the previous week)*100. Tropism results were available from 141/175 (80.6%) subjects screened: 87/141 (60%) were R5 and 74/87 (85%) were finally included in the study. Their median age was 48 years, 16% were women, 31% were MSM, 36% had CDC category C at study entry, 62% were HCV+ and 10% were HBV+. Median CD4+ counts were 616 cells/mm(3) at screening, and median nadir CD4+ counts were 143 cells/mm(3). Previous ART included PIs in 46 (62%) subjects, NNRTIs in 27 (36%) and integrase inhibitors (INIs) in 1 (2%). The main reasons for treatment change were dyslipidemia (42%), gastrointestinal symptoms (22%), and liver toxicity (15%). MVC was given alongside TDF/FTC in 40 (54%) subjects, ABC/3TC in 30 (40%), AZT/3TC in 2 (3%) and ABC/TDF in 2 (3%). Sixty-two (84%) subjects maintained VL<50 c/mL through week 48, whereas 12 (16%) discontinued treatment: two (3%) withdrew informed consent, one (1%) had a R5→X4 shift in HIV tropism between the screening and baseline visits, one (1%) was lost to follow-up, one (1%) developed an ART-related adverse event (rash), two (3%) died due to non-study-related causes (1 myocardial infarction at week 0 and 1 lung cancer at week 36), and five (7%) developed protocol-defined virological

  9. Genotypic tropism testing in proviral DNA to guide maraviroc initiation in aviremic subjects: 48-week analysis of the PROTEST study

    Directory of Open Access Journals (Sweden)

    Federico Garcia

    2014-11-01

    Full Text Available Introduction: In a previous interim 24-week virological safety analysis of the PROTEST study (1, initiation of Maraviroc (MVC plus 2 nucleoside reverse-transcriptase inhibitors (NRTIs in aviremic subjects based on genotypic tropism testing of proviral HIV-1 DNA was associated with low rates of virological failure. Here we present the final 48-week analysis of the study. Methods: PROTEST was a phase 4, prospective, single-arm clinical trial (ID: NCT01378910 carried on in 24 HIV care centres in Spain. Maraviroc-naïve HIV-1-positive adults with HIV-1 RNA (VL 10% in a singleton, initiated MVC with 2 NRTIs and were followed for 48 weeks. Virological failure was defined as two consecutive VL>50 c/mL. Recent adherence was calculated as: (# pills taken/# pills prescribed during the previous week*100. Results: Tropism results were available from 141/175 (80.6% subjects screened: 87/141 (60% were R5 and 74/87 (85% were finally included in the study. Their median age was 48 years, 16% were women, 31% were MSM, 36% had CDC category C at study entry, 62% were HCV+ and 10% were HBV+. Median CD4+ counts were 616 cells/mm3 at screening, and median nadir CD4+ counts were 143 cells/mm3. Previous ART included PIs in 46 (62% subjects, NNRTIs in 27 (36% and integrase inhibitors (INIs in 1 (2%. The main reasons for treatment change were dyslipidemia (42%, gastrointestinal symptoms (22%, and liver toxicity (15%. MVC was given alongside TDF/FTC in 40 (54% subjects, ABC/3TC in 30 (40%, AZT/3TC in 2 (3% and ABC/TDF in 2 (3%. Sixty-two (84% subjects maintained VL<50 c/mL through week 48, whereas 12 (16% discontinued treatment: two (3% withdrew informed consent, one (1% had a R5→X4 shift in HIV tropism between the screening and baseline visits, one (1% was lost to follow-up, one (1% developed an ART-related adverse event (rash, two (3% died due to non-study-related causes (1 myocardial infarction at week 0 and 1 lung cancer at week 36, and five (7% developed protocol

  10. HIV DNA Integration

    Science.gov (United States)

    Craigie, Robert; Bushman, Frederic D.

    2012-01-01

    Retroviruses are distinguished from other viruses by two characteristic steps in the viral replication cycle. The first is reverse transcription, which results in the production of a double-stranded DNA copy of the viral RNA genome, and the second is integration, which results in covalent attachment of the DNA copy to host cell DNA. The initial catalytic steps of the integration reaction are performed by the virus-encoded integrase (IN) protein. The chemistry of the IN-mediated DNA breaking and joining steps is well worked out, and structures of IN-DNA complexes have now clarified how the overall complex assembles. Methods developed during these studies were adapted for identification of IN inhibitors, which received FDA approval for use in patients in 2007. At the chromosomal level, HIV integration is strongly favored in active transcription units, which may promote efficient viral gene expression after integration. HIV IN binds to the cellular factor LEDGF/p75, which promotes efficient infection and tethers IN to favored target sites. The HIV integration machinery must also interact with many additional host factors during infection, including nuclear trafficking and pore proteins during nuclear entry, histones during initial target capture, and DNA repair proteins during completion of the DNA joining steps. Models for some of the molecular mechanisms involved have been proposed, but important details remain to be clarified. PMID:22762018

  11. Structure and possible function of a G-quadruplex in the long terminal repeat of the proviral HIV-1 genome.

    Science.gov (United States)

    De Nicola, Beatrice; Lech, Christopher J; Heddi, Brahim; Regmi, Sagar; Frasson, Ilaria; Perrone, Rosalba; Richter, Sara N; Phan, Anh Tuân

    2016-07-27

    The long terminal repeat (LTR) of the proviral human immunodeficiency virus (HIV)-1 genome is integral to virus transcription and host cell infection. The guanine-rich U3 region within the LTR promoter, previously shown to form G-quadruplex structures, represents an attractive target to inhibit HIV transcription and replication. In this work, we report the structure of a biologically relevant G-quadruplex within the LTR promoter region of HIV-1. The guanine-rich sequence designated LTR-IV forms a well-defined structure in physiological cationic solution. The nuclear magnetic resonance (NMR) structure of this sequence reveals a parallel-stranded G-quadruplex containing a single-nucleotide thymine bulge, which participates in a conserved stacking interaction with a neighboring single-nucleotide adenine loop. Transcription analysis in a HIV-1 replication competent cell indicates that the LTR-IV region may act as a modulator of G-quadruplex formation in the LTR promoter. Consequently, the LTR-IV G-quadruplex structure presented within this work could represent a valuable target for the design of HIV therapeutics. © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.

  12. Strategies for rapidly mapping proviral integration sites and assessing cardiogenic potential of nascent human induced pluripotent stem cell clones.

    Science.gov (United States)

    Dambrot, Cheryl; Buermans, Henk P J; Varga, Eszter; Kosmidis, Georgios; Langenberg, Karin; Casini, Simona; Elliott, David A; Dinnyes, Andras; Atsma, Douwe E; Mummery, Christine L; Braam, Stefan R; Davis, Richard P

    2014-10-01

    Recent methodological advances have improved the ease and efficiency of generating human induced pluripotent stem cells (hiPSCs), but this now typically results in a greater number of hiPSC clones being derived than can be wholly characterized. It is therefore imperative that methods are developed which facilitate rapid selection of hiPSC clones most suited for the downstream research aims. Here we describe a combination of procedures enabling the simultaneous screening of multiple clones to determine their genomic integrity as well as their cardiac differentiation potential within two weeks of the putative reprogrammed colonies initially appearing. By coupling splinkerette-PCR with Ion Torrent sequencing, we could ascertain the number and map the proviral integration sites in lentiviral-reprogrammed hiPSCs. In parallel, we developed an effective cardiac differentiation protocol that generated functional cardiomyocytes within 10 days without requiring line-specific optimization for any of the six independent human pluripotent stem cell lines tested. Finally, to demonstrate the scalable potential of these procedures, we picked 20 nascent iPSC clones and performed these independent assays concurrently. Before the clones required passaging, we were able to identify clones with a single integrated copy of the reprogramming vector and robust cardiac differentiation potential for further analysis. Copyright © 2014 Elsevier Inc. All rights reserved.

  13. TRAIL signaling is proinflammatory and proviral in a murine model of rhinovirus 1B infection.

    Science.gov (United States)

    Girkin, Jason L; Hatchwell, Luke M; Collison, Adam M; Starkey, Malcolm R; Hansbro, Philip M; Yagita, Hideo; Foster, Paul S; Mattes, Joerg

    2017-01-01

    the aim of this study is to elucidate the role of TRAIL during rhinovirus (RV) infection in vivo. Naïve wild-type and tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)-deficient (Tnfsf10(-/-)) BALB/c mice were infected intranasally with RV1B. In separate experiments, Tnfsf10(-/-) mice were sensitized and challenged via the airway route with house dust mite (HDM) to induce allergic airways disease and then challenged with RVIB or UV-RVIB. Airway hyperreactivity (AHR) was invasively assessed as total airways resistance in response to increasing methacholine challenge and inflammation was assessed in bronchoalveolar lavage fluid at multiple time points postinfection. Chemokines were quantified by ELISA of whole lung lysates and viral load was determined by quantitative RT-PCR and tissue culture infective dose (TCID50). Human airway epithelial cells (BEAS2B) were infected with RV1B and stimulated with recombinant TRAIL or neutralizing anti-TRAIL antibodies and viral titer assessed by TCID50 HDM-challenged Tnfsf10(-/-) mice were protected against RV-induced AHR and had suppressed cellular infiltration in the airways upon RV infection. Chemokine C-X-C-motif ligand 2 (CXCL2) production was suppressed in naïve Tnfsf10(-/-) mice infected with RV1B, with less RV1B detected 24 h postinfection. This was associated with reduced apoptotic cell death and a reduction of interferon (IFN)-λ2/3 but not IFN-α or IFN-β. TRAIL stimulation increased, whereas anti-TRAIL antibodies reduced viral replication in RV1B-infected BEAS2B cells in vitro. In conclusion, TRAIL promotes RV-induced AHR, inflammation and RV1B replication, implicating this molecule and its downstream signaling pathways as a possible target for the amelioration of RV1B-induced allergic and nonallergic lung inflammation and AHR. Copyright © 2017 the American Physiological Society.

  14. Genetic modelling of PIM proteins in cancer: proviral tagging, cooperation with oncogenes, tumor suppressor genes and carcinogens.

    Directory of Open Access Journals (Sweden)

    Enara eAguirre

    2014-05-01

    Full Text Available The PIM proteins, which were initially discovered as proviral insertion sites in Moloney murine leukemia virus infection, are a family of highly homologous serine/threonine kinases that have been reported to be overexpressed in hematological malignancies and solid tumors. The PIM proteins have also been associated with metastasis and overall treatment responses and implicated in the regulation of apoptosis, metabolism, the cell cycle, and homing and migration, which makes these proteins interesting targets for anticancer drug discovery. The use of retroviral insertional mutagenesis and refined approaches such as complementation tagging has allowed the identification of myc, pim and a third group of genes (including bmi1 and gfi1 as complementing genes in lymphomagenesis. Moreover, mouse modeling of human cancer has provided an understanding of the molecular pathways that are involved in tumor initiation and progression at the physiological level. In particular, genetically modified mice have allowed researchers to further elucidate the role of each of the Pim isoforms in various tumor types. PIM kinases have been identified as weak oncogenes because experimental overexpression in lymphoid tissue, prostate and liver induces tumors at a relatively low incidence and with a long latency. However, very strong synergistic tumorigenicity between Pim1/2 and c-Myc and other oncogenes has been observed in lymphoid tissues. Mouse models have also been used to study whether the inhibition of specific PIM isoforms is required to prevent carcinogen-induced sarcomas, indicating that the absence of Pim2 and Pim3 greatly reduces sarcoma growth and bone invasion; the extent of this effect is similar to that observed in the absence of all 3 isoforms. This review will summarize some of the animal models that have been used to understand the isoform-specific contribution of PIM kinases to tumorigenesis.

  15. Dynamics of 103K/N and 184M/V HIV-1 drug resistant populations: relative comparison in plasma virus RNA versus CD45RO+T cell proviral DNA

    DEFF Research Database (Denmark)

    Jakobsen, Martin Roelsgaard; Tolstrup, M; Bertelsen, L

    2007-01-01

    and to investigate the expression of resistance mutations (103N and 184V) and dynamic interactions between proviral DNA and plasma virions. STUDY DESIGN: A clinical cross-sectional study, including 11 patients on lamivudine efavirenz and/or nevirapine therapy. The viral populations were determined by an assay based...... population with linked mutations (103N and 184V) was detected in two patients after more than 2 years of non-NNRTI HAART. CONCLUSION: The ARMS assay is useful for detecting viral quasi-species containing efavirenz and lamivudine resistant mutations in plasma virions and in proviral DNA. Data suggest...

  16. Detection and quantification of proviral HIV-1 184 M/V in circulating CD4(+) T cells of patients on HAART with a viremia less than 1000 copies/ml

    DEFF Research Database (Denmark)

    Mohey, Rajesh; Jørgensen, Anne Louise; Møller, Bjarne K

    2005-01-01

    proviral HIV-1 was detected and quantified by a specific and sensitive assay combining a TaqMan real-time PCR analysis with the amplification-refractory mutation system (ARMS) principle. Results Fifty-six percent of patients with low-level viremia had 184V in the CD4+ T cellular DNA compartment as compared...

  17. High prevalence of HIV-1 transmitted drug-resistance mutations from proviral DNA massively parallel sequencing data of therapy-naïve chronically infected Brazilian blood donors.

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    Rodrigo Pessôa

    Full Text Available An improved understanding of the prevalence of low-abundance transmitted drug-resistance mutations (TDRM in therapy-naïve HIV-1-infected patients may help determine which patients are the best candidates for therapy. In this study, we aimed to obtain a comprehensive picture of the evolving HIV-1 TDRM across the massive parallel sequences (MPS of the viral entire proviral genome in a well-characterized Brazilian blood donor naïve to antiretroviral drugs.The MPS data from 128 samples used in the analysis were sourced from Brazilian blood donors and were previously classified by less-sensitive (LS or "detuned" enzyme immunoassay as non-recent or longstanding HIV-1 infections. The Stanford HIV Resistance Database (HIVDBv 6.2 and IAS-USA mutation lists were used to interpret the pattern of drug resistance. The minority variants with TDRM were identified using a threshold of ≥ 1.0% and ≤ 20% of the reads sequenced. The rate of TDRM in the MPS data of the proviral genome were compared with the corresponding published consensus sequences of their plasma viruses.No TDRM were detected in the integrase or envelope regions. The overall prevalence of TDRM in the protease (PR and reverse transcriptase (RT regions of the HIV-1 pol gene was 44.5% (57/128, including any mutations to the nucleoside analogue reverse transcriptase inhibitors (NRTI and non-nucleoside analogue reverse transcriptase inhibitors (NNRTI. Of the 57 subjects, 43 (75.4% harbored a minority variant containing at least one clinically relevant TDRM. Among the 43 subjects, 33 (76.7% had detectable minority resistant variants to NRTIs, 6 (13.9% to NNRTIs, and 16 (37.2% to PR inhibitors. The comparison of viral sequences in both sources, plasma and cells, would have detected 48 DNA provirus disclosed TDRM by MPS previously missed by plasma bulk analysis.Our findings revealed a high prevalence of TDRM found in this group, as the use of MPS drastically increased the detection of these

  18. The novel immunosuppressive protein kinase C inhibitor sotrastaurin has no pro-viral effects on the replication cycle of hepatitis B or C virus.

    Directory of Open Access Journals (Sweden)

    Thomas von Hahn

    Full Text Available The pan-protein kinase C (PKC inhibitor sotrastaurin (AEB071 is a novel immunosuppressant currently in phase II trials for immunosuppression after solid organ transplantation. Besides T-cell activation, PKC affects numerous cellular processes that are potentially important for the replication of hepatitis B virus (HBV and hepatitis C virus (HCV, major blood-borne pathogens prevalent in solid organ transplant recipients. This study uses state of the art virological assays to assess the direct, non-immune mediated effects of sotrastaurin on HBV and HCV. Most importantly, sotrastaurin had no pro-viral effect on either HBV or HCV. In the presence of high concentrations of sotrastaurin, well above those used clinically and close to levels where cytotoxic effects become detectable, there was a reduction of HCV and HBV replication. This reduction is very likely due to cytotoxic and/or anti-proliferative effects rather than direct anti-viral activity of the drug. Replication cycle stages other than genome replication such as viral cell entry and spread of HCV infection directly between adjacent cells was clearly unaffected by sotrastaurin. These data support the evaluation of sotrastaurin in HBV and/or HCV infected transplant recipients.

  19. High viral load in lymph nodes and latent human immunodeficiency virus (HIV) in peripheral blood cells of HIV-1-infected chimpanzees.

    OpenAIRE

    Saksela, K; Muchmore, E; Girard, M; Fultz, P; Baltimore, D

    1993-01-01

    We have examined human immunodeficiency virus type 1 (HIV-1) infection in chimpanzees by analyzing HIV-1 DNA and RNA in lymph nodes and peripheral mononuclear cells (PBMCs). Like certain asymptomatic HIV-infected persons, these chimpanzees had no detectable viral replication in their PBMCs. However, viral replication and a high viral load were observed in the lymphatic tissue. Despite the absence of viral replication in PBMCs, 1/1,000 to 1/10,000 of the PBMCs contained HIV-1 proviral DNA, and...

  20. Genetic composition of replication competent clonal HIV-1 variants isolated from peripheral blood mononuclear cells (PBMC), HIV-1 proviral DNA from PBMC and HIV-1 RNA in serum in the course of HIV-1 infection.

    Science.gov (United States)

    Edo-Matas, Diana; van Gils, Marit J; Bowles, Emma J; Navis, Marjon; Rachinger, Andrea; Boeser-Nunnink, Brigitte; Stewart-Jones, Guillaume B; Kootstra, Neeltje A; van 't Wout, Angélique B; Schuitemaker, Hanneke

    2010-09-30

    The HIV-1 quasispecies in peripheral blood mononuclear cells (PBMC) is considered to be a mix of actively replicating, latent, and archived viruses and may be genetically distinct from HIV-1 variants in plasma that are considered to be recently produced. Here we analyzed the genetic relationship between gp160 env sequences from replication competent clonal HIV-1 variants that were isolated from PBMC and from contemporaneous HIV-1 RNA in serum and HIV-1 proviral DNA in PBMC of four longitudinally studied therapy naïve HIV-1 infected individuals. Replication competent clonal HIV-1 variants, HIV-1 RNA from serum, and HIV-1 proviral DNA from PBMC formed a single virus population at most time points analyzed. However, an under-representation in serum of HIV-1 sequences with predicted CXCR4 usage was sometimes observed implying that the analysis of viral sequences from different sources may provide a more complete assessment of the viral quasispecies in peripheral blood in vivo. Copyright 2010 Elsevier Inc. All rights reserved.

  1. Pegylated Interferon alfa-2a monotherapy results in suppression of HIV type 1 replication and decreased cell-associated HIV DNA integration.

    Science.gov (United States)

    Azzoni, Livio; Foulkes, Andrea S; Papasavvas, Emmanouil; Mexas, Angela M; Lynn, Kenneth M; Mounzer, Karam; Tebas, Pablo; Jacobson, Jeffrey M; Frank, Ian; Busch, Michael P; Deeks, Steven G; Carrington, Mary; O'Doherty, Una; Kostman, Jay; Montaner, Luis J

    2013-01-15

    Antiretroviral therapy (ART)-mediated immune reconstitution fails to restore the capacity of the immune system to spontaneously control human immunodeficiency virus (HIV) replication. A total of 23 HIV type 1 (HIV-1)-infected, virologically suppressed subjects receiving ART (CD4(+) T-cell count, >450 cells/μL) were randomly assigned to have 180 μg/week (for arm A) or 90 μg/week (for arm B) of pegylated (Peg) interferon alfa-2a added to their current ART regimen. After 5 weeks, ART was interrupted, and Peg-interferon alfa-2a was continued for up to 12 weeks (the primary end point), with an option to continue to 24 weeks. End points included virologic failure (viral load, ≥ 400 copies/mL) and adverse events. Residual viral load and HIV-1 DNA integration were also assessed. At week 12 of Peg-interferon alfa-2a monotherapy, viral suppression was observed in 9 of 20 subjects (45%), a significantly greater proportion than expected (arm A, P = .0088; arm B, P = .0010; combined arms, P interferon alfa-2a immunotherapy resulted in control of HIV replication and decreased HIV-1 integration, supporting a role for immunomediated approaches in HIV suppression and/or eradication. NCT00594880.

  2. Load, and Modifies the Immune Response in a Patient with HAM/TSP

    Directory of Open Access Journals (Sweden)

    Davi Tanajura Costa

    2012-01-01

    Full Text Available The human T-cell lymphotropic virus type 1 (HTLV-1 is the known causative agent of a chronic neurologic condition known as HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP. Although several therapies have been evaluated for HAM/TSP, none have been approved for use in humans. In this paper, we describe a 55-year-old female patient with HAM/TSP who was treated with interferon beta-1a. This patient, in comparison to 20 female patients with HAM/TSP who were not treated, showed improvement in urinary symptoms over four years of therapy, as well as a reduction in HTLV-1 proviral load and serum cytokine levels typically observed in HAM/TSP. This improved outcome merits further controlled studies on the use and efficacy of interferon beta-1a as a therapy for HAM/TSP.

  3. Carbohydrate Loading.

    Science.gov (United States)

    Csernus, Marilyn

    Carbohydrate loading is a frequently used technique to improve performance by altering an athlete's diet. The objective is to increase glycogen stored in muscles for use in prolonged strenuous exercise. For two to three days, the athlete consumes a diet that is low in carbohydrates and high in fat and protein while continuing to exercise and…

  4. Meticulous plasma isolation is essential to avoid false low-level viraemia in Roche Cobas HIV-1 viral load assays.

    Science.gov (United States)

    Mortier, Virginie; Vancoillie, Leen; Dauwe, Kenny; Staelens, Delfien; Demecheleer, Els; Schauvliege, Marlies; Dinakis, Sylvie; Van Maerken, Tom; Dessilly, Géraldine; Ruelle, Jean; Verhofstede, Chris

    2017-10-24

    Pre-analytical sample processing is often overlooked as a potential cause of inaccurate assay results. Here we demonstrate how plasma, extracted from standard EDTA- containing blood collection tubes, may contain traces of blood cells consequently resulting in a false low-level HIV-1 viral load when using Roche Cobas HIV-1 assays. The presence of human DNA in Roche Cobas 4800 RNA extracts and in RNA extracts from the Abbott HIV-1 RealTime assay was assessed by quantifying the human albumin gene by means of qPCR. RNA was extracted from plasma samples before and after an additional centrifugation and tested for viral load and DNA contamination. The relation between total DNA content and viral load was defined. Elevated concentrations of genomic DNA were detected in 28 out of 100 Cobas 4800 extracts and were significantly more frequent in samples processed outside of the Aids Reference Laboratory. An association between genomic DNA presence and spurious low-level viremia results was demonstrated. Supplementary centrifugation of plasma before RNA extraction eliminated the contamination and the false viremia. Plasma isolated from standard EDTA-containing blood collection tubes may contain traces of HIV DNA leading to false viral load results above the clinical cut-off. Supplementary centrifugation of plasma before viral load analysis may eliminate the occurrence of this spurious low-level viremia.

  5. Estimation of bovine leukemia virus (BLV) proviral load harbored by lymphocyte subpopulations in BLV-infected cattle at the subclinical stage of enzootic bovine leucosis using BLV-CoCoMo-qPCR

    OpenAIRE

    Panei, Carlos Javier; Takeshima, Shin-nosuke; Omori, Takashi; Nunoya, Tetsuo; Davis, William C.; Ishizaki, Hiroshi; Matoba, Kazuhiro; Aida, Yoko

    2013-01-01

    Background Bovine leukemia virus (BLV) is associated with enzootic bovine leukosis (EBL), which is the most common neoplastic disease of cattle. BLV infection may remain clinically silent at the aleukemic (AL) stage, cause persistent lymphocytosis (PL), or, more rarely, B cell lymphoma. BLV has been identified in B cells, CD2+ T cells, CD3+ T cells, CD4+ T cells, CD8+ T cells, ?/? T cells, monocytes, and granulocytes in infected cattle that do not have tumors, although the most consistently i...

  6. Load testing circuit

    DEFF Research Database (Denmark)

    2009-01-01

    A load testing circuit a circuit tests the load impedance of a load connected to an amplifier. The load impedance includes a first terminal and a second terminal, the load testing circuit comprising a signal generator providing a test signal of a defined bandwidth to the first terminal of the load...

  7. Electrical load detection aparatus

    DEFF Research Database (Denmark)

    2010-01-01

    A load detection technique for a load comprising multiple frequency-dependant sub-loads comprises measuring a representation of the impedance characteristic of the load; providing stored representations of a multiplicity of impedance characteristics of the load; each one of the stored representat...

  8. Distribution load estimation (DLE)

    Energy Technology Data Exchange (ETDEWEB)

    Seppaelae, A.; Lehtonen, M. [VTT Energy, Espoo (Finland)

    1998-08-01

    The load research has produced customer class load models to convert the customers` annual energy consumption to hourly load values. The reliability of load models applied from a nation-wide sample is limited in any specific network because many local circumstances are different from utility to utility and time to time. Therefore there is a need to find improvements to the load models or, in general, improvements to the load estimates. In Distribution Load Estimation (DLE) the measurements from the network are utilized to improve the customer class load models. The results of DLE will be new load models that better correspond to the loading of the distribution network but are still close to the original load models obtained by load research. The principal data flow of DLE is presented

  9. Distribution load estimation - DLE

    Energy Technology Data Exchange (ETDEWEB)

    Seppaelae, A. [VTT Energy, Espoo (Finland)

    1996-12-31

    The load research project has produced statistical information in the form of load models to convert the figures of annual energy consumption to hourly load values. The reliability of load models is limited to a certain network because many local circumstances are different from utility to utility and time to time. Therefore there is a need to make improvements in the load models. Distribution load estimation (DLE) is the method developed here to improve load estimates from the load models. The method is also quite cheap to apply as it utilises information that is already available in SCADA systems

  10. Carbohydrate-Loading Diet

    Science.gov (United States)

    ... of your calories from carbohydrates. The role of carbohydrates Carbohydrates, also known as starches and sugars, are ... to consume some energy sources during your event. Carbohydrate loading Carbohydrate loading is done the week before ...

  11. Spatial electric load forecasting

    CERN Document Server

    Willis, H Lee

    2002-01-01

    Spatial Electric Load Forecasting Consumer Demand for Power and ReliabilityCoincidence and Load BehaviorLoad Curve and End-Use ModelingWeather and Electric LoadWeather Design Criteria and Forecast NormalizationSpatial Load Growth BehaviorSpatial Forecast Accuracy and Error MeasuresTrending MethodsSimulation Method: Basic ConceptsA Detailed Look at the Simulation MethodBasics of Computerized SimulationAnalytical Building Blocks for Spatial SimulationAdvanced Elements of Computerized SimulationHybrid Trending-Simulation MethodsAdvanced

  12. Cognitive Load and Cooperation

    DEFF Research Database (Denmark)

    Døssing, Felix Sebastian; Piovesan, Marco; Wengström, Erik Roland

    2017-01-01

    We study the effect of intuitive and reflective processes on cooperation using cognitive load. Compared with time constraint, which has been used in the previous literature, cognitive load is a more direct way to block reflective processes, and thus a more suitable way to study the link between...... intuition and cooperation. Using a repeated public goods game, we study the effect of different levels of cognitive load on contributions. We show that a higher cognitive load increases the initial level of cooperation. In particular, subjects are significantly less likely to fully free ride under high...... cognitive load....

  13. Evaluation of feline monocyte-derived dendritic cells loaded with internally inactivated virus as a vaccine against feline immunodeficiency virus.

    Science.gov (United States)

    Freer, Giulia; Matteucci, Donatella; Mazzetti, Paola; Tarabella, Francesca; Catalucci, Valentina; Ricci, Enrica; Merico, Antonio; Bozzacco, Leonia; Pistello, Mauro; Bendinelli, Mauro

    2008-03-01

    Dendritic cells are the only antigen-presenting cells that can present exogenous antigens to both helper and cytolytic T cells and prime Th1-type or Th2-type cellular immune responses. Given their unique immune functions, dendritic cells are considered attractive "live adjuvants" for vaccination and immunotherapy against cancer and infectious diseases. The present study was carried out to assess whether the reinjection of autologous monocyte-derived dendritic cells loaded with an aldithriol-2-inactivated primary isolate of feline immune deficiency virus (FIV) was able to elicit protective immune responses against the homologous virus in naive cats. Vaccine efficacy was assessed by monitoring immune responses and, finally, by challenge with the homologous virus of vaccinated, mock-vaccinated, and healthy cats. The outcome of challenge was followed by measuring cellular and antibody responses and viral and proviral loads and quantitating FIV by isolation and a count of CD4(+)/CD8(+) T cells in blood. Vaccinated animals exhibited clearly evident FIV-specific peripheral blood mononuclear cell proliferation and antibody titers in response to immunization; however, they became infected with the challenge virus at rates comparable to those of control animals.

  14. Optimisation of load control

    Energy Technology Data Exchange (ETDEWEB)

    Koponen, P. [VTT Energy, Espoo (Finland)

    1998-08-01

    Electricity cannot be stored in large quantities. That is why the electricity supply and consumption are always almost equal in large power supply systems. If this balance were disturbed beyond stability, the system or a part of it would collapse until a new stable equilibrium is reached. The balance between supply and consumption is mainly maintained by controlling the power production, but also the electricity consumption or, in other words, the load is controlled. Controlling the load of the power supply system is important, if easily controllable power production capacity is limited. Temporary shortage of capacity causes high peaks in the energy price in the electricity market. Load control either reduces the electricity consumption during peak consumption and peak price or moves electricity consumption to some other time. The project Optimisation of Load Control is a part of the EDISON research program for distribution automation. The following areas were studied: Optimization of space heating and ventilation, when electricity price is time variable, load control model in power purchase optimization, optimization of direct load control sequences, interaction between load control optimization and power purchase optimization, literature on load control, optimization methods and field tests and response models of direct load control and the effects of the electricity market deregulation on load control. An overview of the main results is given in this chapter

  15. Concentrated loads on concrete

    DEFF Research Database (Denmark)

    Lorenzen, Karen Grøndahl; Nielsen, Mogens Peter

    1997-01-01

    This report deals with concentrated loads on concrete.A new upper bound solution in the axisymmetrical case of a point load in the center of the end face of a cylinder is developed.Based on previous work dealing with failure mechanisms and upper bound solutions, new approximate formulas are devel......This report deals with concentrated loads on concrete.A new upper bound solution in the axisymmetrical case of a point load in the center of the end face of a cylinder is developed.Based on previous work dealing with failure mechanisms and upper bound solutions, new approximate formulas...

  16. Electrical load modeling

    Energy Technology Data Exchange (ETDEWEB)

    Valgas, Helio Moreira; Pinto, Roberto del Giudice R.; Franca, Carlos [Companhia Energetica de Minas Gerais (CEMIG), Belo Horizonte, MG (Brazil); Lambert-Torres, Germano; Silva, Alexandre P. Alves da; Pires, Robson Celso; Costa Junior, Roberto Affonso [Escola Federal de Engenharia de Itajuba, MG (Brazil)

    1994-12-31

    Accurate dynamic load models allow more precise calculations of power system controls and stability limits, which are critical mainly in the operation planning of power systems. This paper describes the development of a computer program (software) for static and dynamic load model studies using the measurement approach for the CEMIG system. Two dynamic load model structures are developed and tested. A procedure for applying a set of measured data from an on-line transient recording system to develop load models is described. (author) 6 refs., 17 figs.

  17. Critical Axial Load

    Directory of Open Access Journals (Sweden)

    Walt Wells

    2008-01-01

    Full Text Available Our objective in this paper is to solve a second order differential equation for a long, simply supported column member subjected to a lateral axial load using Heun's numerical method. We will use the solution to find the critical load at which the column member will fail due to buckling. We will calculate this load using Euler's derived analytical approach for an exact solution, as well as Euler's Numerical Method. We will then compare the three calculated values to see how much they deviate from one another. During the critical load calculation, it will be necessary to calculate the moment of inertia for the column member.

  18. Load Induced Blindness

    Science.gov (United States)

    Macdonald, James S. P.; Lavie, Nilli

    2008-01-01

    Although the perceptual load theory of attention has stimulated a great deal of research, evidence for the role of perceptual load in determining perception has typically relied on indirect measures that infer perception from distractor effects on reaction times or neural activity (see N. Lavie, 2005, for a review). Here we varied the level of…

  19. Mechanism isolates load weighing cell during lifting of load

    Science.gov (United States)

    Haigler, J. S.

    1966-01-01

    Load weighing cell used in conjuction with a hoist is isolated during lifting and manipulation of the load. A simple mechanism, attached to a crane hook, provides a screw adjustment for engaging the load cell during weighing of the load and isolating it from lift forces during hoisting of the load.

  20. Load flow analysis using decoupled fuzzy load flow under critical ...

    African Journals Online (AJOL)

    user

    The conventional load flow methods like Newton-Raphson load flow (NRLF), Fast Decoupled load flow (FDLF) provide poor performance under critical conditions such as high R/X ratio, heavily loading condition etc. Exploiting the decoupling properties of power system, reliable fuzzy load flow is developed to overcome the ...

  1. Load Balancing Scientific Applications

    Energy Technology Data Exchange (ETDEWEB)

    Pearce, Olga Tkachyshyn [Texas A & M Univ., College Station, TX (United States)

    2014-12-01

    The largest supercomputers have millions of independent processors, and concurrency levels are rapidly increasing. For ideal efficiency, developers of the simulations that run on these machines must ensure that computational work is evenly balanced among processors. Assigning work evenly is challenging because many large modern parallel codes simulate behavior of physical systems that evolve over time, and their workloads change over time. Furthermore, the cost of imbalanced load increases with scale because most large-scale scientific simulations today use a Single Program Multiple Data (SPMD) parallel programming model, and an increasing number of processors will wait for the slowest one at the synchronization points. To address load imbalance, many large-scale parallel applications use dynamic load balance algorithms to redistribute work evenly. The research objective of this dissertation is to develop methods to decide when and how to load balance the application, and to balance it effectively and affordably. We measure and evaluate the computational load of the application, and develop strategies to decide when and how to correct the imbalance. Depending on the simulation, a fast, local load balance algorithm may be suitable, or a more sophisticated and expensive algorithm may be required. We developed a model for comparison of load balance algorithms for a specific state of the simulation that enables the selection of a balancing algorithm that will minimize overall runtime.

  2. LOADING SIMULATION PROGRAM C

    Data.gov (United States)

    U.S. Environmental Protection Agency — LSPC is the Loading Simulation Program in C++, a watershed modeling system that includes streamlined Hydrologic Simulation Program Fortran (HSPF) algorithms for...

  3. Plug Load Data

    Data.gov (United States)

    National Aeronautics and Space Administration — We provide MATLAB binary files (.mat) and comma separated values files of data collected from a pilot study of a plug load management system that allows for the...

  4. LOADING SIMULATION PROGRAM C

    Science.gov (United States)

    LSPC is the Loading Simulation Program in C++, a watershed modeling system that includes streamlined Hydrologic Simulation Program Fortran (HSPF) algorithms for simulating hydrology, sediment, and general water quality

  5. HIV Viral Load

    Science.gov (United States)

    ... Chains Sex Hormone Binding Globulin (SHBG) Shiga toxin-producing Escherichia coli Sickle Cell Tests Sirolimus Smooth Muscle ... used each time. Will exercise, nutrition, and other lifestyle modifications help decrease my HIV viral load? There ...

  6. Lumbriculus variegatus loading study

    Data.gov (United States)

    U.S. Environmental Protection Agency — Results from sediment bioaccumulation tests with Lumbriculus variegatus with evaluating the effects of organism loading density. This dataset is associated with the...

  7. Static Loads Test Facility

    Data.gov (United States)

    Federal Laboratory Consortium — FUNCTION: Provides the capability to perform large-scale structural loads testing on spacecraft and other structures. Results from these tests can be used to verify...

  8. Composite Load Model Evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Ning; Qiao, Hong (Amy)

    2007-09-30

    The WECC load modeling task force has dedicated its effort in the past few years to develop a composite load model that can represent behaviors of different end-user components. The modeling structure of the composite load model is recommended by the WECC load modeling task force. GE Energy has implemented this composite load model with a new function CMPLDW in its power system simulation software package, PSLF. For the last several years, Bonneville Power Administration (BPA) has taken the lead and collaborated with GE Energy to develop the new composite load model. Pacific Northwest National Laboratory (PNNL) and BPA joint force and conducted the evaluation of the CMPLDW and test its parameter settings to make sure that: • the model initializes properly, • all the parameter settings are functioning, and • the simulation results are as expected. The PNNL effort focused on testing the CMPLDW in a 4-bus system. An exhaustive testing on each parameter setting has been performed to guarantee each setting works. This report is a summary of the PNNL testing results and conclusions.

  9. Load power device, system and method of load control and management employing load identification

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Yi; Luebke, Charles John; Schoepf, Thomas J.

    2018-01-09

    A load power device includes a power input, at least one power output for at least one load, a plurality of sensors structured to sense voltage and current at the at least one power output, and a processor. The processor provides: (a) load identification based upon the sensed voltage and current, and (b) load control and management based upon the load identification.

  10. Systematic Review of the Use of Dried Blood Spots for Monitoring HIV Viral Load and for Early Infant Diagnosis

    Science.gov (United States)

    Smit, Pieter W.; Sollis, Kimberly A.; Fiscus, Susan; Ford, Nathan; Vitoria, Marco; Essajee, Shaffiq; Barnett, David; Cheng, Ben; Crowe, Suzanne M.; Denny, Thomas; Landay, Alan; Stevens, Wendy; Habiyambere, Vincent; Perriens, Joseph H.; Peeling, Rosanna W.

    2014-01-01

    Background Dried blood spots (DBS) have been used as alternative specimens to plasma to increase access to HIV viral load (VL) monitoring and early infant diagnosis (EID) in remote settings. We systematically reviewed evidence on the performance of DBS compared to plasma for VL monitoring and EID. Methods and Findings Thirteen peer reviewed HIV VL publications and five HIV EID papers were included. Depending on the technology and the viral load distribution in the study population, the percentage of DBS samples that are within 0.5 log of VL in plasma ranged from 52–100%. Because the input sample volume is much smaller in a blood spot, there is a risk of false negatives with DBS. Sensitivity of DBS VL was found to be 78–100% compared to plasma at VL below 1000 copies/ml, but this increased to 100% at a threshold of 5000 copies/ml. Unlike a plasma VL test which measures only cell free HIV RNA, a DBS VL also measures proviral DNA as well as cell-associated RNA, potentially leading to false positive results when using DBS. The systematic review showed that specificity was close to 100% at DBS VL above 5000 copies/ml, and this threshold would be the most reliable for predicting true virologic failure using DBS. For early infant diagnosis, DBS has a sensitivity of 100% compared to fresh whole blood or plasma in all studies. Conclusions Although limited data are available for EID, DBS offer a highly sensitive and specific sampling strategy to make viral load monitoring and early infant diagnosis more accessible in remote settings. A standardized approach for sampling, storing, and processing DBS samples would be essential to allow successful implementation. Trial Registration PROSPERO Registration #: CRD42013003621. PMID:24603442

  11. Systematic review of the use of dried blood spots for monitoring HIV viral load and for early infant diagnosis.

    Directory of Open Access Journals (Sweden)

    Pieter W Smit

    Full Text Available BACKGROUND: Dried blood spots (DBS have been used as alternative specimens to plasma to increase access to HIV viral load (VL monitoring and early infant diagnosis (EID in remote settings. We systematically reviewed evidence on the performance of DBS compared to plasma for VL monitoring and EID. METHODS AND FINDINGS: Thirteen peer reviewed HIV VL publications and five HIV EID papers were included. Depending on the technology and the viral load distribution in the study population, the percentage of DBS samples that are within 0.5 log of VL in plasma ranged from 52-100%. Because the input sample volume is much smaller in a blood spot, there is a risk of false negatives with DBS. Sensitivity of DBS VL was found to be 78-100% compared to plasma at VL below 1000 copies/ml, but this increased to 100% at a threshold of 5000 copies/ml. Unlike a plasma VL test which measures only cell free HIV RNA, a DBS VL also measures proviral DNA as well as cell-associated RNA, potentially leading to false positive results when using DBS. The systematic review showed that specificity was close to 100% at DBS VL above 5000 copies/ml, and this threshold would be the most reliable for predicting true virologic failure using DBS. For early infant diagnosis, DBS has a sensitivity of 100% compared to fresh whole blood or plasma in all studies. CONCLUSIONS: Although limited data are available for EID, DBS offer a highly sensitive and specific sampling strategy to make viral load monitoring and early infant diagnosis more accessible in remote settings. A standardized approach for sampling, storing, and processing DBS samples would be essential to allow successful implementation. TRIAL REGISTRATION: PROSPERO Registration #: CRD42013003621.

  12. Dielectrically Loaded Biconical Antennas

    Science.gov (United States)

    Nusseibeh, Fouad Ahmed

    1995-01-01

    Biconical antennas are of great interest to those who deal with broadband applications including the transmission/reception of pulses. In particular, wide-angle conical antennas are an attractive choice in many applications including Electronic Support Measures (ESM) and the measurements of transient surface currents and charge densities on aircraft. Dielectric loading in the interior region of a conical antenna can be used to reduce the size of the antenna especially at low frequencies and/or for structural strength. Therefore, having an analytical solution for the input impedance and the frequency response is very helpful in optimizing the design and understanding the behavior of the antenna. From the quasi-analytical solution for the input impedance and the electric field of a wide-angle conical antenna, it can be seen that the dielectric loading in the antenna region improves the input impedance at low frequencies, but increases the number of resonance points and the magnitude of these peaks. When an inhomogeneous dielectric load is used, the magnitude of the resonance peaks is decreased (depending on the way the load is distributed), improving the input impedance of the antenna significantly. Introducing a dielectric load in the interior region of an electrically short receiving cone makes the antenna behave as an electrically longer antenna. However, this is not true for the case for electrical1y long antennas. For the case of pulse transmission, the dielectric load affects only the amplitude. Of course, if the dielectric fills the whole space, both transmitting and receiving antennas behave as electrically longer antennas.

  13. Wave Loads on Cylinders

    DEFF Research Database (Denmark)

    Burcharth, H. F.; Frigaard, Peter

    1989-01-01

    Wave loads may be defined as time varying forces on a body resulting from the wave induced flow fields which surrounds the body in whole or in part. Such unsteady fluid forces are the net result of pressure and shear forces integrated over the instantaneous wetted area.......Wave loads may be defined as time varying forces on a body resulting from the wave induced flow fields which surrounds the body in whole or in part. Such unsteady fluid forces are the net result of pressure and shear forces integrated over the instantaneous wetted area....

  14. Load research and load estimation in electricity distribution

    Energy Technology Data Exchange (ETDEWEB)

    Seppaelae, A. [VTT Energy, Espoo (Finland). Energy Systems

    1996-12-31

    The topics introduced in this thesis are: the Finnish load research project, a simple form customer class load model, analysis of the origins of customers load distribution, a method for the estimation of the confidence interval of customer loads and Distribution Load Estimation (DLE) which utilises both the load models and measurements from distribution networks. The Finnish load research project started in 1983. The project was initially coordinated by the Association of Finnish Electric Utilities and 40 utilities joined the project. Now there are over 1000 customer hourly load recordings in a database. A simple form customer class load model is introduced. The model is designed to be practical for most utility applications and has been used by the Finnish utilities for several years. The only variable of the model is the customers annual energy consumption. The model gives the customers average hourly load and standard deviation for a selected month, day and hour. The statistical distribution of customer loads is studied and a model for customer electric load variation is developed. The model results in a lognormal distribution as an extreme case. Using the `simple form load model`, a method for estimating confidence intervals (confidence limits) of customer hourly load is developed. The two methods selected for final analysis are based on normal and lognormal distribution estimated in a simplified manner. The estimation of several cumulated customer class loads is also analysed. Customer class load estimation which combines the information from load models and distribution network load measurements is developed. This method, called Distribution Load Estimation (DLE), utilises information already available in the utilities databases and is thus easy to apply

  15. Laterally loaded masonry

    DEFF Research Database (Denmark)

    Raun Gottfredsen, F.

    stress and increasing shear. The results show a transition to pure friction as the cohesion is gradually destroyed. An interface model of a mortar joint that can take into account this aspect has been developed. Laterally loaded masonry panels have also been tested and it is found to be characteristic...

  16. Fuel Load (FL)

    Science.gov (United States)

    Duncan C. Lutes; Robert E. Keane

    2006-01-01

    The Fuel Load method (FL) is used to sample dead and down woody debris, determine depth of the duff/ litter profile, estimate the proportion of litter in the profile, and estimate total vegetative cover and dead vegetative cover. Down woody debris (DWD) is sampled using the planar intercept technique based on the methodology developed by Brown (1974). Pieces of dead...

  17. Probabilistic Load Flow

    DEFF Research Database (Denmark)

    Chen, Peiyuan; Chen, Zhe; Bak-Jensen, Birgitte

    2008-01-01

    This paper reviews the development of the probabilistic load flow (PLF) techniques. Applications of the PLF techniques in different areas of power system steady-state analysis are also discussed. The purpose of the review is to identify different available PLF techniques and their corresponding...

  18. Robust surgery loading

    NARCIS (Netherlands)

    Hans, Elias W.; Wullink, Gerhard; van Houdenhoven, Mark; Kazemier, Geert

    2008-01-01

    We consider the robust surgery loading problem for a hospital’s operating theatre department, which concerns assigning surgeries and sufficient planned slack to operating room days. The objective is to maximize capacity utilization and minimize the risk of overtime, and thus cancelled patients. This

  19. Duration of load revisited

    DEFF Research Database (Denmark)

    Hoffmeyer, Preben; Sørensen, John Dalsgaard

    2007-01-01

    A duration of load study representing 13 years of testing was recently terminated. Preliminary results have been published over the years. This paper represents the final account of the study, which was focused on the influ-ence of moisture content on time to failure for structural timber subject...

  20. Load research manual. Volume 1. Load research procedures

    Energy Technology Data Exchange (ETDEWEB)

    Brandenburg, L.; Clarkson, G.; Grund, Jr., C.; Leo, J.; Asbury, J.; Brandon-Brown, F.; Derderian, H.; Mueller, R.; Swaroop, R.

    1980-11-01

    This three-volume manual presents technical guidelines for electric utility load research. Special attention is given to issues raised by the load data reporting requirements of the Public Utility Regulatory Policies Act of 1978 and to problems faced by smaller utilities that are initiating load research programs. In Volumes 1 and 2, procedures are suggested for determining data requirements for load research, establishing the size and customer composition of a load survey sample, selecting and using equipment to record customer electricity usage, processing data tapes from the recording equipment, and analyzing the data. Statistical techniques used in customer sampling are discussed in detail. The costs of load research also are estimated, and ongoing load research programs at three utilities are described. The manual includes guides to load research literature and glossaries of load research and statistical terms.

  1. Heavy-Load Lifting

    DEFF Research Database (Denmark)

    Bloomquist, Kira; Oturai, Peter; Steele, Megan L

    2017-01-01

    PURPOSE: Despite a paucity of evidence, prevention guidelines typically advise avoidance of heavy lifting in an effort to protect against breast cancer-related lymphedema. This study compared acute responses in arm swelling and related symptoms after low- and heavy-load resistance exercise among...... women at risk of lymphedema while receiving adjuvant taxane-based chemotherapy. METHODS: This is a randomized, cross-over equivalence trial. Women receiving adjuvant taxane-based chemotherapy for breast cancer who had undergone axillary lymph node dissection (n=21) participated in low- (60-65% 1...... repetition maximum (RM), two sets of 15-20 repetitions) and heavy-load (85-90% 1RM, three sets of 5-8 repetition) upper-extremity resistance exercise separated by a one-week wash-out period. Swelling was determined by bioimpedance spectroscopy and dual energy x-ray absorptiometry, with breast cancer...

  2. Load responsive hydrodynamic bearing

    Science.gov (United States)

    Kalsi, Manmohan S.; Somogyi, Dezso; Dietle, Lannie L.

    2002-01-01

    A load responsive hydrodynamic bearing is provided in the form of a thrust bearing or journal bearing for supporting, guiding and lubricating a relatively rotatable member to minimize wear thereof responsive to relative rotation under severe load. In the space between spaced relatively rotatable members and in the presence of a liquid or grease lubricant, one or more continuous ring shaped integral generally circular bearing bodies each define at least one dynamic surface and a plurality of support regions. Each of the support regions defines a static surface which is oriented in generally opposed relation with the dynamic surface for contact with one of the relatively rotatable members. A plurality of flexing regions are defined by the generally circular body of the bearing and are integral with and located between adjacent support regions. Each of the flexing regions has a first beam-like element being connected by an integral flexible hinge with one of the support regions and a second beam-like element having an integral flexible hinge connection with an adjacent support region. A least one local weakening geometry of the flexing region is located intermediate the first and second beam-like elements. In response to application of load from one of the relatively rotatable elements to the bearing, the beam-like elements and the local weakening geometry become flexed, causing the dynamic surface to deform and establish a hydrodynamic geometry for wedging lubricant into the dynamic interface.

  3. Nutrient and Coliform Loading (NCL)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This is a database of available fecal coliform bacteria, fecal streptococci bacteria, and nutrient loading data. Loading for contaminants other than fecal coliform...

  4. Load Estimation from Modal Parameters

    DEFF Research Database (Denmark)

    Aenlle, Manuel López; Brincker, Rune; Fernández, Pelayo Fernández

    2007-01-01

    In Natural Input Modal Analysis the modal parameters are estimated just from the responses while the loading is not recorded. However, engineers are sometimes interested in knowing some features of the loading acting on a structure. In this paper, a procedure to determine the loading from a FRF...... the accuracy in the load estimation. Finally, the results of an experimental program carried out on a simple structure are presented....

  5. Research of Impact Load in Large Electrohydraulic Load Simulator

    Directory of Open Access Journals (Sweden)

    Yongguang Liu

    2014-01-01

    Full Text Available The stronger impact load will appear in the initial phase when the large electric cylinder is tested in the hardware-in-loop simulation. In this paper, the mathematical model is built based on AMESim, and then the reason of the impact load is investigated through analyzing the changing tendency of parameters in the simulation results. The inhibition methods of impact load are presented according to the structural invariability principle and applied to the actual system. The final experimental result indicates that the impact load is inhibited, which provides a good experimental condition for the electric cylinder and promotes the study of large load simulator.

  6. Pollution Load Estimation Based on Characteristic Section Load Method

    Science.gov (United States)

    Zhu, Lei; Song, JinXi; Liu, WanQing

    2017-12-01

    Weihe River Watershed above Linjiacun Section is taken as the research objective in this paper and COD is chosen as the water quality parameter. According to the discharge characteristics of point source pollutions and non-point source pollutions, a new method to estimate pollution loads-Characteristic Section Load Method(CSLM) is proposed and point source pollution and non-point source pollution loads of Weihe River Watershed above Linjiacun Section are calculated in the rainy, normal and dry season in the year 2007. The results show that the monthly point source pollution loads of Weihe River Watershed above Linjiacun Section are discharged stably, the monthly non-point source pollution loads of Weihe River Watershed above Linjiacun Section change greatly, the non-point source pollution load proportions of total pollution load of COD are gradually decreased in the rainy, normal and wet periods.

  7. Android Fully Loaded

    CERN Document Server

    Huddleston, Rob

    2012-01-01

    Fully loaded with the latest tricks and tips on your new Android! Android smartphones are so hot, they're soaring past iPhones on the sales charts. And the second edition of this muscular little book is equally impressive--it's packed with tips and tricks for getting the very most out of your latest-generation Android device. Start Facebooking and tweeting with your Android mobile, scan barcodes to get pricing and product reviews, download your favorite TV shows--the book is positively bursting with practical and fun how-tos. Topics run the gamut from using speech recognition, location-based m

  8. Variable loading roller

    Science.gov (United States)

    Williams, Daniel M.

    1989-01-01

    An automatic loading roller for transmitting torque in traction drive devices in manipulator arm joints includes a two-part camming device having a first cam portion rotatable in place on a shaft by an input torque and a second cam portion coaxially rotatable and translatable having a rotating drive surface thereon for engaging the driven surface of an output roller with a resultant force proportional to the torque transmitted. Complementary helical grooves on the respective cam portions interconnected through ball bearings interacting with those grooves effect the rotation and translation of the second cam portion in response to rotation of the first.

  9. Laterally Loaded Nail-Plates

    DEFF Research Database (Denmark)

    Nielsen, Jacob; Rathkjen, Arne

    Load-displacement curves from about 200 short-term and laterally loaded nail-plate joints are analysed. The nail-plates are from Gang-Nail Systems, type GNA 20 S. The test specimens and the measuring systems are described. The tests are divided into 32 different series. The influence of the number...... of nail row, edge distance, fixed nail-plate, bending direction, unloading, and grain direction, plate and load direction on the load-displacement curves are analysed. Mean load-displacement curves from all the tests are given....

  10. Load Control System Reliability

    Energy Technology Data Exchange (ETDEWEB)

    Trudnowski, Daniel [Montana Tech of the Univ. of Montana, Butte, MT (United States)

    2015-04-03

    This report summarizes the results of the Load Control System Reliability project (DOE Award DE-FC26-06NT42750). The original grant was awarded to Montana Tech April 2006. Follow-on DOE awards and expansions to the project scope occurred August 2007, January 2009, April 2011, and April 2013. In addition to the DOE monies, the project also consisted of matching funds from the states of Montana and Wyoming. Project participants included Montana Tech; the University of Wyoming; Montana State University; NorthWestern Energy, Inc., and MSE. Research focused on two areas: real-time power-system load control methodologies; and, power-system measurement-based stability-assessment operation and control tools. The majority of effort was focused on area 2. Results from the research includes: development of fundamental power-system dynamic concepts, control schemes, and signal-processing algorithms; many papers (including two prize papers) in leading journals and conferences and leadership of IEEE activities; one patent; participation in major actual-system testing in the western North American power system; prototype power-system operation and control software installed and tested at three major North American control centers; and, the incubation of a new commercial-grade operation and control software tool. Work under this grant certainly supported the DOE-OE goals in the area of “Real Time Grid Reliability Management.”

  11. Estimating constituent loads

    Science.gov (United States)

    Cohn, T.A.; DeLong, L.L.; Gilroy, E.J.; Hirsch, R.M.; Wells, D.K.

    1989-01-01

    This paper compares the bias and variance of three procedures that can be used with log linear regression models: the traditional rating curve estimator, a modified rating curve method, and a minimum variance unbiased estimator (MVUE). Analytical derivations of the bias and efficiency of all three estimators are presented. It is shown that for many conditions the traditional and the modified estimator can provide satisfactory estimates. However, other conditions exist where they have substantial bias and a large mean square error. These conditions commonly occur when sample sizes are small, or when loads are estimated during high-flow conditions. The MVUE, however, is unbiased and always performs nearly as well or better than the rating curve estimator or the modified estimator provided that the hypothesis of the log linear model is correct. Since an efficient unbiased estimator is available, there seems to be no reason to employ biased estimators. -from Authors

  12. Load forecasting for supermarket refrigeration

    DEFF Research Database (Denmark)

    Bacher, Peder; Madsen, Henrik; Aalborg Nielsen, Henrik

    This report presents a study of models for forecasting the load for supermarket refrigeration. The data used for building the forecasting models consists of load measurements, local climate measurements and weather forecasts. The load measurements are from a supermarket located in a village...... in Denmark. The load for refrigeration is the sum of all cabinets in the supermarket, both low and medium temperature cabinets, and spans a period of one year. As input to the forecasting models the ambient temperature observed near the supermarket together with weather forecasts are used. Every hour...... the hourly load for refrigeration for the following 42 hours is forecasted. The forecast models are adaptive linear time-series models which are fitted with a computationally efficient recursive least squares scheme. The dynamic relations between the inputs and the load is modeled by simple transfer...

  13. Load forecasting of supermarket refrigeration

    DEFF Research Database (Denmark)

    Rasmussen, Lisa Buth; Bacher, Peder; Madsen, Henrik

    2016-01-01

    This paper presents a novel study of models for forecasting the electrical load for supermarket refrigeration. The data used for building the models consists of load measurements, local climate measurements and weather forecasts. The load measurements are from a supermarket located in a village...... in Denmark. Every hour the hourly electrical load for refrigeration is forecasted for the following 42 h. The forecast models are adaptive linear time series models. The model has two regimes; one for opening hours and one for closing hours, this is modeled by a regime switching model and two different...

  14. Alaska Village Electric Load Calculator

    Energy Technology Data Exchange (ETDEWEB)

    Devine, M.; Baring-Gould, E. I.

    2004-10-01

    As part of designing a village electric power system, the present and future electric loads must be defined, including both seasonal and daily usage patterns. However, in many cases, detailed electric load information is not readily available. NREL developed the Alaska Village Electric Load Calculator to help estimate the electricity requirements in a village given basic information about the types of facilities located within the community. The purpose of this report is to explain how the load calculator was developed and to provide instructions on its use so that organizations can then use this model to calculate expected electrical energy usage.

  15. Metamaterial Loadings for Waveguide Miniaturization

    CERN Document Server

    Odabasi, H

    2013-01-01

    We show that a rectangular metallic waveguide loaded with metamaterial elements consisting of electric-field coupled (ELC) resonators placed at the side walls can operate well below the cutoff frequency of the respective unloaded waveguide. The dispersion diagrams indicate that propagating modes in ELC-loaded waveguides are of forward-type for both TE and TM modes. We also study the dispersion diagram and transmission characteristics of rectangular metallic waveguides simultaneously loaded with ELCs and split ring resonators (SRRs). Such doubly-loaded waveguides can support both forward wave and backward waves, and provide independent control of the propagation characteristics for the respective modes.

  16. electrical load survey electrical load survey and forecast

    African Journals Online (AJOL)

    eobe

    paper reports the results of electrical load demand and forecast for Elebu rural community located in Kwara State,. Nigeria. The expected peak ... Keywords: hybrid system, renewable energy, optimization, electrical energy, load survey and forecasts. 1. ..... vehicle renewable energy, Monaco, March 26-29,. 2009, pp. 1-9.

  17. Crane-Load Contact Sensor

    Science.gov (United States)

    Youngquist, Robert; Mata, Carlos; Cox, Robert

    2005-01-01

    An electronic instrument has been developed as a prototype of a portable crane-load contact sensor. Such a sensor could be helpful in an application in which the load rests on a base in a horizontal position determined by vertical alignment pins (see Figure 1). If the crane is not positioned to lift the load precisely vertically, then the load can be expected to swing once it has been lifted clear of the pins. If the load is especially heavy, large, and/or fragile, it could hurt workers and/or damage itself and nearby objects. By indicating whether the load remains in contact with the pins when it has been lifted a fraction of the length of the pins, the crane-load contact sensor helps the crane operator determine whether it is safe to lift the load clear of the pins: If there is contact, then the load is resting against the sides of the pins and, hence, it may not be safe to lift; if contact is occasionally broken, then the load is probably not resting against the pins, so it should be safe to lift. It is assumed that the load and base, or at least the pins and the surfaces of the alignment holes in the load, are electrically conductive, so the instrument can use electrical contact to indicate mechanical contact. However, DC resistance cannot be used as an indicator of contact for the following reasons: The load and the base are both electrically grounded through cables (the load is grounded through the lifting cable of the crane) to prevent discharge of static electricity. In other words, the DC resistance between the load and the pins is always low, as though they were always in direct contact. Therefore, instead of DC resistance, the instrument utilizes the AC electrical impedance between the pins and the load. The signal frequency used in the measurement is high enough (.1 MHz) that the impedance contributed by the cables and the electrical ground network of the building in which the crane and the base are situated is significantly greater than the contact

  18. Probabilistic Load Models for Simulating the Impact of Load Management

    DEFF Research Database (Denmark)

    Chen, Peiyuan; Bak-Jensen, Birgitte; Chen, Zhe

    2009-01-01

    to simulate the impact of load management. The joint-normal model is superior in modeling the tail region of the hourly load distribution and implementing the change of hourly standard deviation. Whereas the AR(12) model requires much less parameter and is superior in modeling the autocorrelation......This paper analyzes a distribution system load time series through autocorrelation coefficient, power spectral density, probabilistic distribution and quantile value. Two probabilistic load models, i.e. the joint-normal model and the autoregressive model of order 12 (AR(12)), are proposed....... It is concluded that the AR(12) model is favored with limited measurement data and that the joint-normal model may provide better results with a large data set. Both models can be applied in general to model load time series and used in time-sequential simulation of distribution system planning....

  19. Fatigue Reliability under Random Loads

    DEFF Research Database (Denmark)

    Talreja, R.

    1979-01-01

    We consider the problem of estimating the probability of survival (non-failure) and the probability of safe operation (strength greater than a limiting value) of structures subjected to random loads. These probabilities are formulated in terms of the probability distributions of the loads and the...... propagation stage. The consequences of this behaviour on the fatigue reliability are discussed....

  20. Loading Conditions and Longitudinal Strength

    DEFF Research Database (Denmark)

    Sørensen, Herman

    1995-01-01

    Methods for the calculation of the lightweight of the ship.Loading conditions satisfying draught, trim and intact stability requirements and analysis of the corresponding stillwater longitudinal strength.......Methods for the calculation of the lightweight of the ship.Loading conditions satisfying draught, trim and intact stability requirements and analysis of the corresponding stillwater longitudinal strength....

  1. Load forecasting of supermarket refrigeration

    DEFF Research Database (Denmark)

    Rasmussen, Lisa Buth; Bacher, Peder; Madsen, Henrik

    2016-01-01

    This paper presents a novel study of models for forecasting the electrical load for supermarket refrigeration. The data used for building the models consists of load measurements, local climate measurements and weather forecasts. The load measurements are from a supermarket located in a village...... in Denmark. Every hour the hourly electrical load for refrigeration is forecasted for the following 42 h. The forecast models are adaptive linear time series models. The model has two regimes; one for opening hours and one for closing hours, this is modeled by a regime switching model and two different...... methods for predicting the regimes are tested. The dynamic relation between the weather and the load is modeled by simple transfer functions and the non-linearities are described using spline functions. The results are thoroughly evaluated and it is shown that the spline functions are suitable...

  2. Hydrodynamic loading of tensegrity structures

    Science.gov (United States)

    Wroldsen, Anders S.; Johansen, Vegar; Skelton, Robert E.; Sørensen, Asgeir J.

    2006-03-01

    This paper introduces hydrodynamic loads for tensegrity structures, to examine their behavior in marine environments. Wave compliant structures are of general interest when considering large marine structures, and we are motivated by the aquaculture industry where new concepts are investigated in order to make offshore installations for seafood production. This paper adds to the existing models and software simulations of tensegrity structures exposed to environmental loading from waves and current. A number of simulations are run to show behavior of the structure as a function of pretension level and string stiffness for a given loading condition.

  3. 14 CFR 23.301 - Loads.

    Science.gov (United States)

    2010-01-01

    ... load would significantly change the distribution of external or internal loads, this redistribution...) and ultimate loads (limit loads multiplied by prescribed factors of safety). Unless otherwise provided... validated by flight test measurement unless the methods used for determining those loading conditions are...

  4. Structural Impact of Construction Loads

    Science.gov (United States)

    2012-08-01

    Numerous bridge construction accidents have occurred across the country because of construction loadings, which are an underemphasized : topic in many DOT specifications and design manuals. Bridge girders are least stable when they are subjected to c...

  5. Training load quantification in triathlon

    OpenAIRE

    Cejuela Anta, Roberto; Esteve-Lanao, Jonathan

    2011-01-01

    There are different Indices of Training Stress of varying complexity, to quantification Training load. Examples include the training impulse (TRIMP), the session (RPE), Lucia’s TRIMP or Summated Zone Score. But the triathlon, a sport to be combined where there are interactions between different segments, is a complication when it comes to quantify the training. The aim of this paper is to review current methods of quantification, and to propose a scale to quantify the training load in triathl...

  6. Wind Structure and Wind Loading

    DEFF Research Database (Denmark)

    Brorsen, Michael

    The purpose of this note is to provide a short description of wind, i.e. of the flow in the atmosphere of the Earth and the loading caused by wind on structures. The description comprises: causes to the generation of windhe interaction between wind and the surface of the Earthhe stochastic nature...... of windhe interaction between wind and structures, where it is shown that wind loading depends strongly on this interaction...

  7. Aircraft ditching loads simulation tool

    OpenAIRE

    Bonanni, A.; Vandewaeter, L.; Havill, C.; Kanyoo, P.; Taunton, D.J.; Blake, J.I.R.; Cropper, E.; Hancock, S.

    2015-01-01

    The present work presents a novel methodology developed for calculating the steady loads acting on aircraft structures in the event of ditching in water. It represents the preliminary result of Stirling Dynamics as part of a NATEP research project. The overall objective of the project is to expand the capabilities of the Stirling Dynamics proprietary software SD-GLOAD (originally designed for ground and crash loads dynamic simulations) to aircraft ditching simulations. The methodology present...

  8. Load Estimation from Natural input Modal Analysis

    OpenAIRE

    Aenlle, Manuel López; Brincker, Rune; Canteli, Alfonso Fernández

    2005-01-01

    One application of Natural Input Modal Analysis consists in estimating the unknown load acting on structures such as wind loads, wave loads, traffic loads, etc. In this paper, a procedure to determine loading from a truncated modal model, as well as the results of an experimental testing programme, are presented. The method involves the inversion of the FRF matrix partly solving the numerical problems that appear because of the truncation of the modal space. However, the error in the load est...

  9. Calibration set up for load cells

    Science.gov (United States)

    Rao, T. V. Govinda; Venkatesh, C. S.; Shivashankar, N.

    1989-05-01

    The planning, designing, fabrication, and calibration of 30, 50, and 100 ton tension load cells and 30 ton shear load cells are described. The tension load cells are for monitoring the force developed by earth moving vehicles and the shear load cells are for monitoring the load that tipplers unload form platform to ground. The shear load cells were incorporated into a rotary wagon tippler.

  10. Self-aligning biaxial load frame

    Science.gov (United States)

    Ward, M.B.; Epstein, J.S.; Lloyd, W.R.

    1994-01-18

    An self-aligning biaxial loading apparatus for use in testing the strength of specimens while maintaining a constant specimen centroid during the loading operation. The self-aligning biaxial loading apparatus consists of a load frame and two load assemblies for imparting two independent perpendicular forces upon a test specimen. The constant test specimen centroid is maintained by providing elements for linear motion of the load frame relative to a fixed cross head, and by alignment and linear motion elements of one load assembly relative to the load frame. 3 figures.

  11. Inefficient viral replication of bovine leukemia virus induced by spontaneous deletion mutation in the G4 gene.

    Science.gov (United States)

    Murakami, Hironobu; Uchiyama, Jumpei; Nikaido, Sae; Sato, Reiichiro; Sakaguchi, Masahiro; Tsukamoto, Kenji

    2016-10-01

    Enzootic bovine leucosis is caused by bovine leukemia virus (BLV) infection, which is highly prevalent in several regions of the world and significantly impacts the livestock industry. In BLV infection, the proviral load in the blood reflects disease progression. Although the BLV genome is highly conserved among retroviruses, genetic variation has been reported. However, the relationship between proviral load and genetic variation is poorly understood. In this study, we investigated the changes in proviral load in BLV-infected cattle in Japan and then identified and analysed a BLV strain pvAF967 that had a static proviral load. First, examining the proviral load in the aleukaemic cattle in 2014 and 2015, cow AF967 showed a static proviral load, while the other cows showed significant increases in proviral load. Sequencing the provirus in cow AF967 showed a deletion of 12 nt located in the G4 gene. An in vitro assay system using BLV molecular clone was set up to evaluate viral replication and production. In this in vitro assay, the deletion mutation in the G4 gene resulted in a significant decrease in viral replication and production. In addition, we showed that the deletion mutation did not affect the viral transcriptional activity of Tax protein, which is also important for virus replication. The emergence of strain pvAF967 that showed a static proviral load, combined with other retrovirus evolutionary traits, suggests that some BLV strains may have evolved to be symbiotic with cattle.

  12. A gravity loading countermeasure skinsuit

    Science.gov (United States)

    Waldie, James M.; Newman, Dava J.

    2011-04-01

    Despite the use of several countermeasures, significant physiological deconditioning still occurs during long duration spaceflight. Bone loss - primarily due to the absence of loading in microgravity - is perhaps the greatest challenge to resolve. This paper describes a conceptual Gravity Loading Countermeasure Skinsuit (GLCS) that induces loading on the body to mimic standing and - when integrated with other countermeasures - exercising on Earth. Comfort, mobility and other operational issues were explored during a pilot study carried out in parabolic flight for prototype suits worn by three subjects. Compared to the 1- or 2-stage Russian Pingvin Suits, the elastic mesh of the GLCS can create a loading regime that gradually increases in hundreds of stages from the shoulders to the feet, thereby reproducing the weight-bearing regime normally imparted by gravity with much higher resolution. Modelling shows that the skinsuit requires less than 10 mmHg (1.3 kPa) of compression for three subjects of varied gender, height and mass. Negligible mobility restriction and excellent comfort properties were found during the parabolic flights, which suggests that crewmembers should be able to work normally, exercise or sleep while wearing the suit. The suit may also serve as a practical 1 g harness for exercise countermeasures and vibration applications to improve dynamic loading.

  13. Mental load: helping clinical learners.

    Science.gov (United States)

    White, Geoff

    2011-09-01

    The quality of an individual's learning is influenced significantly by the quantity of mental processing they are required to manage in a clinical learning situation. Some clinical learning settings require the learner to process high levels of complex knowledge and skills, whilst simultaneously monitoring and responding to challenging social or emotional inputs. This paper introduces the concept of 'cognitive load', its negative impacts upon novice learners in particular, and its real-world implications for teaching and supervision. Narrative review and discussion. The concept of cognitive load is reviewed, and examples of its application to clinical learning and teaching are provided. Teaching and supervision strategies for managing the cognitive load of learners are presented. The clinical teacher has significant capacity to reduce the cognitive load of learners by creating safe and supportive learning environments, establishing trusting relationships with the learner, and implementing structured learning experiences that are designed to support the learner's growth in knowledge, understanding and skills. A threefold focus on the nature of the learning task, the learning environment and the learner's perceptions of these elements, which characterises cognitive load, provides a useful framework for diagnosing poor learning behaviours and maximising learning outcomes. © Blackwell Publishing Ltd 2011.

  14. Inhibition of HIV Expression and Integration in Macrophages by Methylglyoxal-Bis-Guanylhydrazone.

    Science.gov (United States)

    Jin, Xia; McGrath, Michael S; Xu, Hua

    2015-11-01

    Macrophages are a target for infection with HIV and represent one of the viral reservoirs that are relatively resistant to current antiretroviral drugs. Here we demonstrate that methylglyoxal-bis-guanylhydrazone (MGBG), a polyamine analog and potent S-adenosylmethionine decarboxylase inhibitor, decreases HIV expression in monocytes and macrophages. MGBG is selectively concentrated by these cells through a mechanism consistent with active transport by the polyamine transporter. Using a macrophage-tropic reporter virus tagged with the enhanced green fluorescent protein, we demonstrate that MGBG decreases the frequency of HIV-infected cells. The effect is dose dependent and correlates with the production of HIV p24 in culture supernatants. This anti-HIV effect was further confirmed using three macrophage-tropic primary HIV isolates. Viral life cycle mapping studies show that MGBG inhibits HIV DNA integration into the cellular DNA in both monocytes and macrophages. Our work demonstrates for the first time the selective concentration of MGBG by monocytes/macrophages, leading to the inhibition of HIV-1 expression and a reduction in proviral load within macrophage cultures. These results suggest that MGBG may be useful in adjunctive macrophage-targeted therapy for HIV infection. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  15. Ultimate loading of wind turbines

    DEFF Research Database (Denmark)

    Larsen, Gunner Chr.; Ronold, K.; Ejsing Jørgensen, Hans

    1999-01-01

    to establish partial safety factors for design of such components against this failure mode, structuralreliability methods must be applied. This type of analysis accounts for the variability of the external (wind) loading (as addressed in the analyses of the general wind climate) - and thereby the induced......An extreme loading study has been conducted comprising a general wind climate analysis as well as a wind turbine reliability study. In the wind climate analysis, the distribution of the (horizontal) turbulence standard deviation, conditioned on the meanwind speed, has been approximated by fitting......, a design turbulence intensity for off-shore application is proposed which, in the IEC code framework, is applicable for extreme as well as for fatigue loaddetermination. In order to establish a rational method to analyse wind turbine components with respect to failure in ultimate loading, and in addition...

  16. Load flow analysis using decoupled fuzzy load flow under critical ...

    African Journals Online (AJOL)

    user

    mismatch and summation of power mismatches are taken as two inputs for fuzzy logic controller. Considering magnitude of power mismatch and sign of power mismatch, new 25 fuzzy rules are created from two sets of inputs. The proposed Decoupled. Fuzzy Load Flow (FDLF) is applied to IEEE 14 bus, IEEE 30 bus, IEEE ...

  17. RF Loads for Energy Recovery

    CERN Document Server

    Federmann, S; Caspers, F

    2012-01-01

    Different conceptional designs for RF high power loads are presented. One concept implies the use of solid state rectifier modules for direct RF to DC conversion with efficiencies beyond 80%. In addition, robust metallic low-Q resonant structures, capable of operating at high temperatures (>150 ◦C) are discussed. Another design deals with a very high temperature (up to 800 ◦C) air cooled load using a ceramic foam block inside a metal enclosure. This porous ceramic block is the microwave absorber and is not brazed to the metallic enclosure.

  18. Load Estimation by Frequency Domain Decomposition

    DEFF Research Database (Denmark)

    Pedersen, Ivar Chr. Bjerg; Hansen, Søren Mosegaard; Brincker, Rune

    2007-01-01

    When performing operational modal analysis the dynamic loading is unknown, however, once the modal properties of the structure have been estimated, the transfer matrix can be obtained, and the loading can be estimated by inverse filtering. In this paper loads in frequency domain are estimated...... and the errors on the estimated loads are determined....

  19. 14 CFR 27.865 - External loads.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false External loads. 27.865 Section 27.865... STANDARDS: NORMAL CATEGORY ROTORCRAFT Design and Construction External Loads § 27.865 External loads. (a) It must be shown by analysis, test, or both, that the rotorcraft external load attaching means for...

  20. 14 CFR 29.865 - External loads.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false External loads. 29.865 Section 29.865... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction External Loads § 29.865 External loads. (a) It must be shown by analysis, test, or both, that the rotorcraft external load attaching means for...

  1. Analyses of tunnel stability under dynamic loads

    OpenAIRE

    Oraee, B; Hosseini, N.; Oraee, K; Gholinejad, M

    2011-01-01

    Tunnels as any other structures are affected by different loads and stresses. Generally, the loads on tunnels consist of both static and dynamic loads. These loads must both be considered in the tunnel design process. In this paper, the stability state of Jiroft water-transform tunnel is evaluated. Firstly, the in-situ stresses and then using Kirschs equations the induced stresses due to static loads in walls and crown of tunnel are calculated. Consequently, the strain caused by probable eart...

  2. Numerical prediction of slamming loads

    DEFF Research Database (Denmark)

    Seng, Sopheak; Jensen, Jørgen J; Pedersen, Preben T

    2012-01-01

    It is important to include the contribution of the slamming-induced response in the structural design of large vessels with a significant bow flare. At the same time it is a challenge to develop rational tools to determine the slamming-induced loads and the prediction of their occurrence. Today i...

  3. Resource augmentation in load balancing

    NARCIS (Netherlands)

    Y. Azar; L. Epstein (Lea); R. van Stee (Rob)

    1999-01-01

    textabstractWe consider load-balancing in the following setting. The on-line algorithm is allowed to use $n$ machines, whereas the optimal off-line algorithm is limited to $m$ machines, for some fixed $m < n$. We show that while the greedy algorithm has a competitive ratio which decays linearly in

  4. Soil Profiles and Seismic Loading

    Directory of Open Access Journals (Sweden)

    Janotka, V.

    2006-01-01

    Full Text Available The contribution estimates different geotechnical profiles of site condition change and their influences on the computed seismic response spectra and time histories final values and forms applying on the seismic structures loading. The mentioned problems methodics attitude solution is based on the computed seismic motion parameters.

  5. Fracture load of ceramic restorations after fatigue loading.

    Science.gov (United States)

    Baladhandayutham, Balasudha; Lawson, Nathaniel C; Burgess, John O

    2015-08-01

    A clinician must decide what ceramic coping and veneer material to prescribe based on the amount of tooth reduction possible and the desired esthetic outcome of the restoration. The purpose of this in vitro study was to compare the fracture strength of monolithic and bilayered lithium disilicate (IPS e.max) and zirconia (LAVA) crowns at clinically relevant thicknesses after load cycling. Crowns (n=8) were fabricated from 6 groups: 1.2-mm monolithic lithium disilicate, 1.5-mm monolithic lithium disilicate, 1.5-mm bilayered lithium disilicate with hand-layered veneer, 0.6 mm monolithic zirconia, 1.2-mm bilayered zirconia with hand-layered veneer, and 1.2-mm bilayered zirconia with milled veneer (dimension represents thickness at the occlusal pit). Crowns were cemented to identical milled resin dies with resin-modified glass ionomer cement. Cemented crowns were stored at 37°C for 24 hours and load cycled for 200,000 cycles at 25 N at a rate of 40 cycles/minute. The ultimate fracture load for each specimen was measured in a universal testing machine. Data were analyzed with a 1-way ANOVA and Tukey honest significant difference post hoc analysis (α=.05). Mean ±SD fracture load values were 1465 ±330 N for monolithic lithium disilicate (1.2-mm thickness) and 2027 ±365 N (1.5-mm thickness) and 1732 ±315 N for bilayered hand-veneered lithium disilicate (1.5-mm thickness). Fracture loads were 1669 ±311 N for monolithic zirconia crowns (0.6mm thickness), 2625 ±300 N for zirconia milled-veneered (1.2-mm thickness), and 2655 ±590N for zirconia hand-veneered crowns (1.2mm thickness). One-way ANOVA showed a statistically significant difference among the groups (PVeneered zirconia crowns showed the highest fracture strength, 1.2-mm hand veneered zirconia was similar to that of 1.5-mm monolithic zirconia, and all other groups were not statistically different. Crowns of 1.2-mm bilayered zirconia had higher fracture loads than 0.6-mm zirconia or 1.2-mm lithium disilicate

  6. Experimental investigation of ultimate loads

    Energy Technology Data Exchange (ETDEWEB)

    Petersen, S.M.; Larsen, G.C.; Antoniou, I.; Lind, S.O.; Courtney, M. [Risoe National Lab., Wind Energy and Atmospheric Physics, Roskilde (Denmark)

    1999-03-01

    Verification of the structural integrity of a wind turbine involves analysis of fatigue loading as well as ultimate loading. With the trend of persistently growing turbines, the ultimate loading seems to become relatively more important. For wind turbines designed according to the wind conditions prescribed in the IEC-61400 code, the ultimate load is often identified as the leading load parameter. Exemplified by the use of an extensive measurement campaign a procedure for evaluation of the extreme flap-wise bending moments, occurring during normal operating of a wind turbine, is presented. The structural measurements are made on a NEG Micon 650 kW wind turbine erected at a complex high wind site in Oak Creek, California. The turbine is located on the top of a ridge. The prevailing wind direction is perpendicular to the ridge, and the annual mean wind speed is 9.5 m/s. The associated wind field measurement, are taken from two instrumented masts erected less than one rotor diameter in front of the turbine in direction of the prevailing wind direction. Both masts are instrumented at different heights in order to gain insight of the 3D-wind speed structure over the entire rotor plane. Extreme distributions, associated with a recurrence period of 10 minutes, conditioned on the mean wind speed and the turbulence intensity are derived. Combined with the wind climate model proposed in the IEC standard, these distributions are used to predict extreme distributions with recurrence periods equal to one and fifty years, respectively. The synthesis of the conditioned PDF`s and the wind climate model is performed by means of Monte Carlo simulation. (au)

  7. 46 CFR 154.1730 - Ethylene oxide: Loading and off loading.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Ethylene oxide: Loading and off loading. 154.1730... Operating Requirements § 154.1730 Ethylene oxide: Loading and off loading. (a) The master shall ensure that before ethylene oxide is loaded into a cargo tank: (1) The tank is thoroughly clean, dry, and free of...

  8. Potential impact of viral load and genetic makeup of HIV type 1 on mother-to-child transmission: characterization of env-C2V3C3 and nef sequences.

    Science.gov (United States)

    Pádua, Elizabeth; Parreira, Ricardo; Tendeiro, Rita; Nunes, Baltazar; Castela, João; Soares, Isabel; Mouzinho, Ana; Reis, Eduarda; Paixão, Maria Teresa

    2009-11-01

    HIV-1 mother-to-child transmission (MTCT) was evaluated in terms of the molecular characterization of the env and nef genomic regions and quantification of maternal RNA viral loads. Assignment of viral subtype was achieved by direct sequencing of PCR 1172 products amplified from proviral DNA in 45 HIV-1-nontransmitting mothers (NTM), along with 13 pairs of HIV-1-transmitting mothers (TM) and their infected children (C). Analysis of the env C2V3C3 and nef sequences revealed that subtypes G and B, and their genetic combinations (AG, BG), accounted for over 84.5% of all viruses identified. The genetic structure form envA-nefG was the most commonly observed, with a lower frequency in the NTM (13.3%) compared to the TM (23.1%) group. A greater number of genetic forms was observed among NTM, namely the presence of sequences assigned to subtypes D and F, as well as the intergenetic A/J, and C/U, recombinant forms, along with a mosaic provirus with a complex putative envA-nefEGE genetic structure. No significant differences were found when RNA viral loads were evaluated as a function of the viral subtypes. Nevertheless, a relatively high quantification of HIV-1 RNA was obtained in the NTM group, emphasizing the importance of the compliance and effectiveness of therapeutic schemes to control viral replication and reduce the risk of HIV vertical transmission. V3 sequences displaying features associated with the R5 phenotype dominated in both groups. Both C2V3C3 and Nef's functional domains were conserved during HIV-1 vertical transmission.

  9. Load Estimation from Natural input Modal Analysis

    DEFF Research Database (Denmark)

    Aenlle, Manuel López; Brincker, Rune; Canteli, Alfonso Fernández

    2005-01-01

    One application of Natural Input Modal Analysis consists in estimating the unknown load acting on structures such as wind loads, wave loads, traffic loads, etc. In this paper, a procedure to determine loading from a truncated modal model, as well as the results of an experimental testing programme...... estimation. In the experimental program a small structure subjected to vibration was used to estimate the loading from the measurements and the experimental modal space. The modal parameters were estimated by Natural Input Modal Analysis and the scaling factors of the mode shapes obtained by the mass change...

  10. Trailer-loading of horses

    DEFF Research Database (Denmark)

    Hendriksen, Payana; Elmgreen, Katrine; Ladewig, Jan

    2011-01-01

    trailer-loading problems were selected and exposed to trailer-loading. They were randomly assigned to one of the 2 methods. NR consisted of various degrees of pressure (lead rope pulling, whip tapping). Pressure was removed as soon as the horse complied. PR horses were exposed to clicker training......The traditional way to train horses is by the application of negative reinforcement (NR). In the past few years, however, the use of positive reinforcement (PR) has become more common. To evaluate the effectiveness and the possible stressor effect of the 2 training methods, 12 horses showing severe...... and taught to follow a target into the trailer. Heart rate (HR) was recorded every 5 seconds and behavior denoting discomfort was observed using one-zero sampling with 10 seconds sampling intervals. Training was completed when the horse could enter the trailer upon a signal, or was terminated after a maximum...

  11. Efficiency of Capacitively Loaded Converters

    DEFF Research Database (Denmark)

    Andersen, Thomas; Huang, Lina; Andersen, Michael A. E.

    2012-01-01

    This paper explores the characteristic of capacitance versus voltage for dielectric electro active polymer (DEAP) actuator, 2kV polypropylene film capacitor as well as 3kV X7R multi layer ceramic capacitor (MLCC) at the beginning. An energy efficiency for capacitively loaded converters...... is introduced as a definition of efficiency. The calculated and measured efficiency curves for charging DEAP actuator, polypropylene film capacitor and X7R MLCC are provided and compared. The attention has to be paid for the voltage dependent capacitive load, like X7R MLCC, when evaluating the charging...... efficiency of converter. Based on the capacitancevoltage curve, the correct capacitance should be chosen when calculating the stored energy; otherwise misleading optimistic efficiency can always be obtained. Actually, when DEAP actuator is not available at the early developing stage, the voltage independent...

  12. Polymer brushes under high load.

    Directory of Open Access Journals (Sweden)

    Suzanne M Balko

    Full Text Available Polymer coatings are frequently used to provide repulsive forces between surfaces in solution. After 25 years of design and study, a quantitative model to explain and predict repulsion under strong compression is still lacking. Here, we combine experiments, simulations, and theory to study polymer coatings under high loads and demonstrate a validated model for the repulsive forces, proposing that this universal behavior can be predicted from the polymer solution properties.

  13. Fatigue Performance under Multiaxial Loading

    Science.gov (United States)

    1990-01-01

    Fatigue Strength (Study fatigue strength in cor. connect, in box struc.)." Prog. Rpt. 1, Res. Inst. Ishikawajima - Harima Heavy Ind. Co., Ltd., Tokyo, Japan...1," Ishikawajima - Harima Heavy Ind. Co., Ltd. Research Inst., Tokyo, Japan, IIW Doc. No XIII-573-70. Mall, G., and R. Zirn, "Load Carrying Behavior of...1972. Anonymous, "Application of Program Fatigue Test to Member Joints of Hulls," Mitsubishi Heavy Industries LTD, Mitsubishi Technical Bulletin No

  14. Inducer Hydrodynamic Load Measurement Devices

    Science.gov (United States)

    Skelley, Stephen E.; Zoladz, Thomas F.

    2002-01-01

    Marshall Space Flight Center (MSFC) has demonstrated two measurement devices for sensing and resolving the hydrodynamic loads on fluid machinery. The first - a derivative of the six component wind tunnel balance - senses the forces and moments on the rotating device through a weakened shaft section instrumented with a series of strain gauges. This "rotating balance" was designed to directly measure the steady and unsteady hydrodynamic loads on an inducer, thereby defining both the amplitude and frequency content associated with operating in various cavitation modes. The second device - a high frequency response pressure transducer surface mounted on a rotating component - was merely an extension of existing technology for application in water. MSFC has recently completed experimental evaluations of both the rotating balance and surface-mount transducers in a water test loop. The measurement bandwidth of the rotating balance was severely limited by the relative flexibility of the device itself, resulting in an unexpectedly low structural bending mode and invalidating the higher frequency response data. Despite these limitations, measurements confirmed that the integrated loads on the four-bladed inducer respond to both cavitation intensity and cavitation phenomena. Likewise, the surface-mount pressure transducers were subjected to a range of temperatures and flow conditions in a non-rotating environment to record bias shifts and transfer functions between the transducers and a reference device. The pressure transducer static performance was within manufacturer's specifications and dynamic response accurately followed that of the reference.

  15. High Temperature Radio Frequency Loads

    CERN Document Server

    Federmann, S; Grudiev, A; Montesinos, E; Syratchev, I

    2011-01-01

    In the context of energy saving and recovery requirements the design of reliable and robust RF power loads which permit a high outlet temperature and high pressure of the cooling water is desirable. Cooling water arriving at the outlet withmore than 150 ◦C and high pressure has a higher value than water with 50 ◦C under low pressure. Conventional RF power loads containing dielectric and magnetic materials as well as sensitive ceramic windows usually do not permit going much higher than 90 ◦C. Here we present and discuss several design concepts for "metal only" RF high power loads. One concept is the application of magnetic steel corrugated waveguides near cutoff – this concept could find practical use above several GHz. Another solution are resonant structures made of steel to be installed in large waveguides for frequencies of 500 MHz or lower. Similar resonant structures above 100 MHz taking advantage of the rather high losses of normal steel may also be used in coaxial line geometries with large di...

  16. PASSIVE DETECTION OF VEHICLE LOADING

    Energy Technology Data Exchange (ETDEWEB)

    Garrett, A.

    2012-01-03

    The Digital Imaging and Remote Sensing Laboratory (DIRS) at the Rochester Institute of Technology, along with the Savannah River National Laboratory is investigating passive methods to quantify vehicle loading. The research described in this paper investigates multiple vehicle indicators including brake temperature, tire temperature, engine temperature, acceleration and deceleration rates, engine acoustics, suspension response, tire deformation and vibrational response. Our investigation into these variables includes building and implementing a sensing system for data collection as well as multiple full-scale vehicle tests. The sensing system includes; infrared video cameras, triaxial accelerometers, microphones, video cameras and thermocouples. The full scale testing includes both a medium size dump truck and a tractor-trailer truck on closed courses with loads spanning the full range of the vehicle's capacity. Statistical analysis of the collected data is used to determine the effectiveness of each of the indicators for characterizing the weight of a vehicle. The final sensing system will monitor multiple load indicators and combine the results to achieve a more accurate measurement than any of the indicators could provide alone.

  17. Probabilistic Meteorological Characterization for Turbine Loads

    DEFF Research Database (Denmark)

    Kelly, Mark C.; Larsen, Gunner Chr.; Dimitrov, Nikolay Krasimirov

    2014-01-01

    Beyond the existing, limited IEC prescription to describe fatigue loads on wind turbines, we look towards probabilistic characterization of the loads via analogous characterization of the atmospheric flow, particularly for today's "taller" turbines with rotors well above the atmospheric surface...

  18. Acid loading test (pH)

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/003615.htm Acid loading test (pH) To use the sharing features on this page, please enable JavaScript. The acid loading test (pH) measures the ability of the ...

  19. Plug Load Behavioral Change Demonstration Project

    Energy Technology Data Exchange (ETDEWEB)

    Metzger, I.; Kandt, A.; VanGeet, O.

    2011-08-01

    This report documents the methods and results of a plug load study of the Environmental Protection Agency's Region 8 Headquarters in Denver, Colorado, conducted by the National Renewable Energy Laboratory. The study quantified the effect of mechanical and behavioral change approaches on plug load energy reduction and identified effective ways to reduce plug load energy. Load reduction approaches included automated energy management systems and behavioral change strategies.

  20. Simulation of Stochastic Loads for Fatigue Experiments

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard; Brincker, Rune

    A simple direct simulation method for stochastic fatigue load generation is described in this paper. The simulation method is based on the assumption that only the peaks of the load process significantly affect the fatigue life. The method requires the conditional distribution functions of load...... second using an IBM PC. Finally the proposed simulation method for fatigue load generation is tested by comparing some fatigue damage measures obtained by the simulation methods....

  1. System and method employing a minimum distance and a load feature database to identify electric load types of different electric loads

    Science.gov (United States)

    Lu, Bin; Yang, Yi; Sharma, Santosh K; Zambare, Prachi; Madane, Mayura A

    2014-12-23

    A method identifies electric load types of a plurality of different electric loads. The method includes providing a load feature database of a plurality of different electric load types, each of the different electric load types including a first load feature vector having at least four different load features; sensing a voltage signal and a current signal for each of the different electric loads; determining a second load feature vector comprising at least four different load features from the sensed voltage signal and the sensed current signal for a corresponding one of the different electric loads; and identifying by a processor one of the different electric load types by determining a minimum distance of the second load feature vector to the first load feature vector of the different electric load types of the load feature database.

  2. Load Bearing Equipment for Bone and Muscle

    Science.gov (United States)

    Shackelford, Linda; Griffith, Bryan

    2015-01-01

    Resistance exercise on ISS has proven effective in maintaining bone mineral density and muscle mass. Exploration missions require exercise with similar high loads using equipment with less mass and volume and greater safety and reliability than resistance exercise equipment used on ISS (iRED, ARED, FWED). Load Bearing Equipment (LBE) uses each exercising person to create and control the load to the partner.

  3. Plutonium Immobilization Can Loading Preliminary Specifications

    Energy Technology Data Exchange (ETDEWEB)

    Kriikku, E.

    1998-11-25

    This report discusses the Plutonium Immobilization can loading preliminary equipment specifications and includes a process block diagram, process description, equipment list, preliminary equipment specifications, plan and elevation sketches, and some commercial catalogs. This report identifies loading pucks into cans and backfilling cans with helium as the top priority can loading development areas.

  4. 10 CFR 434.512 - Internal loads.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 3 2010-01-01 2010-01-01 false Internal loads. 434.512 Section 434.512 Energy DEPARTMENT... RESIDENTIAL BUILDINGS Building Energy Cost Compliance Alternative § 434.512 Internal loads. 512.1The systems... Schedules. Internal loads for other building types shall be modeled as noted in this subsection. Table 512.2...

  5. 49 CFR 195.110 - External loads.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false External loads. 195.110 Section 195.110 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY... PIPELINE Design Requirements § 195.110 External loads. (a) Anticipated external loads (e.g.), earthquakes...

  6. Load balancing in integrated optical wireless networks

    DEFF Research Database (Denmark)

    Yan, Ying; Dittmann, Lars; Wong, S-W.

    2010-01-01

    In this paper, we tackle the load balancing problem in Integrated Optical Wireless Networks, where cell breathing technique is used to solve congestion by changing the coverage area of a fully loaded cell tower. Our objective is to design a load balancing mechanism which works closely...

  7. 33 CFR 154.510 - Loading arms.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Loading arms. 154.510 Section 154... FACILITIES TRANSFERRING OIL OR HAZARDOUS MATERIAL IN BULK Equipment Requirements § 154.510 Loading arms. (a) Each mechanical loading arm used for transferring oil or hazardous material and placed into service...

  8. Local Dynamic Stability Associated with Load Carrying

    Directory of Open Access Journals (Sweden)

    Jian Liu

    2013-03-01

    Conclusion: Current study confirmed the sensitivity of local dynamic stability measure in load carrying situation. It was concluded that load carrying tasks were associated with declined local dynamic stability, which may result in increased risk of fall accident. This finding has implications in preventing fall accidents associated with occupational load carrying.

  9. Determining large deflections in rectangular combined loaded ...

    Indian Academy of Sciences (India)

    In this study, large deflection of cantilever beams of Ludwick type material subjected to a combined loading consisting of a uniformly distributed load and one vertical concentrated load at the free end was investigated. In calculations, both material and geometrical non-linearity have been considered. Horizontal and vertical ...

  10. Response of Rubble Foundation to Dynamic Loading

    DEFF Research Database (Denmark)

    Burcharth, H. F.; Ibsen, Lars Bo

    1993-01-01

    The soil beneath vertical monolithic structures is subjected to a combination of static load due to the submerged weight of the structure and stochastic non-stationary loads as a result of the wave loads on the vertical wall. The stress conditions in the soil below a foundation exposed to both...

  11. Determining large deflections in rectangular combined loaded ...

    Indian Academy of Sciences (India)

    Abstract. In this study, large deflection of cantilever beams of Ludwick type material subjected to a combined loading consisting of a uniformly distributed load and one vertical concentrated load at the free end was investigated. In calcula- tions, both material and geometrical non-linearity have been considered. Horizon-.

  12. Timber joints under long-term loading

    DEFF Research Database (Denmark)

    Feldborg, T.; Johansen, M.

    This report describes tests and results from stiffness and strength testing of splice joints under long-term loading. During two years of loading the spicimens were exposed to cyclically changing relative humidity. After the loading period the specimens were short-term tested. The connectors were...

  13. Response of Rubble Foundation to Dynamic Loading

    DEFF Research Database (Denmark)

    Burcharth, H. F.; Ibsen, Lars Bo

    1994-01-01

    The soil beneath vertical monolithic structures is subjected to a combination of static load due to the submerged weight of the structure and stochastic non-stationary loads as a result of the wave loads on the vertical wall. The stress conditions in the soil below a foundation exposed to both st...

  14. Wind loads on solar energy systems

    NARCIS (Netherlands)

    Kampen, B.J.M. van; Geurts, C.P.W.; Borsboom, W.A.; Blackmore, P.

    2005-01-01

    Wind loads on solar energy systems are not covered by current wind loading standards. This paper describes results of a parametric study into the wind loads 0on solar energy systems,. which are placed on flat roofs. Wind tunnel measurements have been carried out on a number of configurations. The

  15. Beam heat load in superconducting wigglers

    CERN Document Server

    Casalbuoni, S.

    2013-04-22

    The beam heat load is a fundamental input parameter for the design of superconducting wigglers since it is needed to specify the cooling power. In this presentation I will review the possible beam heat load sources and the measurements of beam heat load performed and planned onto the cold vacuum chambers installed at different synchrotron light sources.

  16. Soil Behavior Under Blast Loading

    Science.gov (United States)

    2010-12-01

    compressive stress of creep loading causes the pore water pressure to increase. If drainage is possible an outflow of water then takes place into...behavior such as creep and temperature-dependency. Those aspects are not discussed here because they are beyond the scopes in this study. 2.2.2...0.00060 0.0012 0.0020 0.0040 0.0060 $ P9 P10 0.0080 0.041 *MAT_USER_DEFINED_MATERIAL_MODELS $ MID RO

  17. Spatial peak-load pricing

    Energy Technology Data Exchange (ETDEWEB)

    Arellano, M. Soledad; Serra, Pablo [Universidad de Chile, Dept. of Industrial Engineering, Santiago (Chile)

    2007-03-15

    This article extends the traditional electricity peak-load pricing model to include transmission costs. In the context of a two-node, two-technology electric power system, where suppliers face inelastic demand, we show that when the marginal plant is located at the energy-importing center, generators located away from that center should pay the marginal capacity transmission cost; otherwise, consumers should bear this cost through capacity payments. Since electric power transmission is a natural monopoly, marginal-cost pricing does not fully cover costs. We propose distributing the revenue deficit among users in proportion to the surplus they derive from the service priced at marginal cost. (Author)

  18. Critical loads - assessment of uncertainty

    Energy Technology Data Exchange (ETDEWEB)

    Barkman, A.

    1998-10-01

    The effects of data uncertainty in applications of the critical loads concept were investigated on different spatial resolutions in Sweden and northern Czech Republic. Critical loads of acidity (CL) were calculated for Sweden using the biogeochemical model PROFILE. Three methods with different structural complexity were used to estimate the adverse effects of S0{sub 2} concentrations in northern Czech Republic. Data uncertainties in the calculated critical loads/levels and exceedances (EX) were assessed using Monte Carlo simulations. Uncertainties within cumulative distribution functions (CDF) were aggregated by accounting for the overlap between site specific confidence intervals. Aggregation of data uncertainties within CDFs resulted in lower CL and higher EX best estimates in comparison with percentiles represented by individual sites. Data uncertainties were consequently found to advocate larger deposition reductions to achieve non-exceedance based on low critical loads estimates on 150 x 150 km resolution. Input data were found to impair the level of differentiation between geographical units at all investigated resolutions. Aggregation of data uncertainty within CDFs involved more constrained confidence intervals for a given percentile. Differentiation as well as identification of grid cells on 150 x 150 km resolution subjected to EX was generally improved. Calculation of the probability of EX was shown to preserve the possibility to differentiate between geographical units. Re-aggregation of the 95%-ile EX on 50 x 50 km resolution generally increased the confidence interval for each percentile. Significant relationships were found between forest decline and the three methods addressing risks induced by S0{sub 2} concentrations. Modifying S0{sub 2} concentrations by accounting for the length of the vegetation period was found to constitute the most useful trade-off between structural complexity, data availability and effects of data uncertainty. Data

  19. Automated Loads Analysis System (ATLAS)

    Science.gov (United States)

    Gardner, Stephen; Frere, Scot; O’Reilly, Patrick

    2013-01-01

    ATLAS is a generalized solution that can be used for launch vehicles. ATLAS is used to produce modal transient analysis and quasi-static analysis results (i.e., accelerations, displacements, and forces) for the payload math models on a specific Shuttle Transport System (STS) flight using the shuttle math model and associated forcing functions. This innovation solves the problem of coupling of payload math models into a shuttle math model. It performs a transient loads analysis simulating liftoff, landing, and all flight events between liftoff and landing. ATLAS utilizes efficient and numerically stable algorithms available in MSC/NASTRAN.

  20. Online load forecasting for supermarket refrigeration

    DEFF Research Database (Denmark)

    Bacher, Peder; Madsen, Henrik; Nielsen, Henrik Aalborg

    2013-01-01

    This paper presents a study of models for forecasting the load for supermarket refrigeration. The data used for building the forecasting models consists of load measurements, local climate measurements and weather forecasts. The load measurements are from a supermarket located in a village...... in Denmark. Every hour the hourly load for refrigeration for the following 42 hours is forecasted. The forecast models are time adaptive linear time-series models. The dynamic relations between the inputs and the load is modeled by simple transfer functions. The system operates in two regimes: one...

  1. Novel Musculoskeletal Loading and Assessment System

    Science.gov (United States)

    Downs, Meghan E.

    2017-01-01

    Ground based and ISS (International Space Station) exercise research have shown that axial loading via two-point loading at the shoulders and load quality (i.e. consistent load and at least 1:1 concentric to eccentric ratio) are extremely important to optimize musculoskeletal adaptations to resistance exercise. The Advanced Resistance Exercise Device (ARED) is on ISS now and is the "state of the art" for resistance exercise capabilities in microgravity; however, the ARED is far too large and power consuming for exploration vehicles. The single cable exercise device design selected for MPCV (Multi-Purpose Crew Vehicle), does not readily allow for the two-point loading at the shoulders.

  2. Concurrent Working Memory Load Can Facilitate Selective Attention: Evidence for Specialized Load

    Science.gov (United States)

    Park, Soojin; Kim, Min-Shik; Chun, Marvin M.

    2007-01-01

    Load theory predicts that concurrent working memory load impairs selective attention and increases distractor interference (N. Lavie, A. Hirst, J. W. de Fockert, & E. Viding, see record 2004-17825-003). Here, the authors present new evidence that the type of concurrent working memory load determines whether load impairs selective attention or not.…

  3. Effect of loading rate on the fracture behavior of nuclear piping materials under cyclic loading conditions

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jin Weon; Choi, Myung Rak [Dept. of Nuclear Engineering, Chosun University, Gwangju (Korea, Republic of); Kim, Yun Jae [Dept. of Mechanical Engineering, Korea University, Seoul (Korea, Republic of)

    2016-12-15

    This study investigated the loading rate effect on the fracture resistance under cyclic loading conditions to understand clearly the fracture behavior of piping materials under seismic conditions. J-R fracture toughness tests were conducted under monotonic and cyclic loading conditions at various displacement rates at room temperature and the operating temperature of nuclear power plants (i.e., 316°C). SA508 Gr.1a low-alloy steel and SA312 TP316 stainless steel piping materials were used for the tests. The fracture resistance under a reversible cyclic load was considerably lower than that under monotonic load regardless of test temperature, material, and loading rate. Under both cyclic and monotonic loading conditions, the fracture behavior of SA312 TP316 stainless steel was independent of the loading rate at both room temperature and 316°C. For SA508 Gr.1a low-alloy steel, the loading rate effect on the fracture behavior was appreciable at 316°C under cyclic and monotonic loading conditions. However, the loading rate effect diminished when the cyclic load ratio of the load (R) was -1. Thus, it was recognized that the fracture behavior of piping materials, including seismic loading characteristics, can be evaluated when tested under a cyclic load of R = -1 at a quasistatic loading rate.

  4. Effect of Loading Rate on the Fracture Behavior of Nuclear Piping Materials Under Cyclic Loading Conditions

    Directory of Open Access Journals (Sweden)

    Jin Weon Kim

    2016-12-01

    Full Text Available This study investigated the loading rate effect on the fracture resistance under cyclic loading conditions to understand clearly the fracture behavior of piping materials under seismic conditions. J–R fracture toughness tests were conducted under monotonic and cyclic loading conditions at various displacement rates at room temperature and the operating temperature of nuclear power plants (i.e., 316°C. SA508 Gr.1a low-alloy steel and SA312 TP316 stainless steel piping materials were used for the tests. The fracture resistance under a reversible cyclic load was considerably lower than that under monotonic load regardless of test temperature, material, and loading rate. Under both cyclic and monotonic loading conditions, the fracture behavior of SA312 TP316 stainless steel was independent of the loading rate at both room temperature and 316°C. For SA508 Gr.1a low-alloy steel, the loading rate effect on the fracture behavior was appreciable at 316°C under cyclic and monotonic loading conditions. However, the loading rate effect diminished when the cyclic load ratio of the load (R was −1. Thus, it was recognized that the fracture behavior of piping materials, including seismic loading characteristics, can be evaluated when tested under a cyclic load of R = −1 at a quasistatic loading rate.

  5. 14 CFR 23.511 - Ground load; unsymmetrical loads on multiple-wheel units.

    Science.gov (United States)

    2010-01-01

    ... multiple-wheel units. 23.511 Section 23.511 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION... CATEGORY AIRPLANES Structure Ground Loads § 23.511 Ground load; unsymmetrical loads on multiple-wheel units... distribution, to the dual wheels and tires in each dual wheel landing gear unit. (c) Deflated tire loads. For...

  6. 14 CFR 25.511 - Ground load: unsymmetrical loads on multiple-wheel units.

    Science.gov (United States)

    2010-01-01

    ... multiple-wheel units. 25.511 Section 25.511 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION... Loads § 25.511 Ground load: unsymmetrical loads on multiple-wheel units. (a) General. Multiple-wheel...-wheel unit; and (2) In determining the total load on a gear unit with respect to the provisions of...

  7. Detection of Unexpected High Correlations between Balance Calibration Loads and Load Residuals

    Science.gov (United States)

    Ulbrich, N.; Volden, T.

    2014-01-01

    An algorithm was developed for the assessment of strain-gage balance calibration data that makes it possible to systematically investigate potential sources of unexpected high correlations between calibration load residuals and applied calibration loads. The algorithm investigates correlations on a load series by load series basis. The linear correlation coefficient is used to quantify the correlations. It is computed for all possible pairs of calibration load residuals and applied calibration loads that can be constructed for the given balance calibration data set. An unexpected high correlation between a load residual and a load is detected if three conditions are met: (i) the absolute value of the correlation coefficient of a residual/load pair exceeds 0.95; (ii) the maximum of the absolute values of the residuals of a load series exceeds 0.25 % of the load capacity; (iii) the load component of the load series is intentionally applied. Data from a baseline calibration of a six-component force balance is used to illustrate the application of the detection algorithm to a real-world data set. This analysis also showed that the detection algorithm can identify load alignment errors as long as repeat load series are contained in the balance calibration data set that do not suffer from load alignment problems.

  8. Low reflectance radio frequency load

    Science.gov (United States)

    Ives, R. Lawrence; Mizuhara, Yosuke M

    2014-04-01

    A load for traveling microwave energy has an absorptive volume defined by cylindrical body enclosed by a first end cap and a second end cap. The first end cap has an aperture for the passage of an input waveguide with a rotating part that is coupled to a reflective mirror. The inner surfaces of the absorptive volume consist of a resistive material or are coated with a coating which absorbs a fraction of incident RF energy, and the remainder of the RF energy reflects. The angle of the reflector and end caps is selected such that reflected RF energy dissipates an increasing percentage of the remaining RF energy at each reflection, and the reflected RF energy which returns to the rotating mirror is directed to the back surface of the rotating reflector, and is not coupled to the input waveguide. Additionally, the reflector may have a surface which generates a more uniform power distribution function axially and laterally, to increase the power handling capability of the RF load. The input waveguide may be corrugated for HE11 mode input energy.

  9. APS high heat load monochromator

    Energy Technology Data Exchange (ETDEWEB)

    Lee, W.K.; Mills, D.

    1993-02-01

    This document contains the design specifications of the APS high heat load (HHL) monochromator and associated accessories as of February 1993. It should be noted that work is continuing on many parts of the monochromator including the mechanical design, crystal cooling designs, etc. Where appropriate, we have tried to add supporting documentation, references to published papers, and calculations from which we based our decisions. The underlying philosophy behind performance specifications of this monochromator was to fabricate a device that would be useful to as many APS users as possible, that is, the design should be as generic as possible. In other words, we believe that this design will be capable of operating on both bending magnet and ID beamlines (with the appropriate changes to the cooling and crystals) with both flat and inclined crystal geometries and with a variety of coolants. It was strongly felt that this monochromator should have good energy scanning capabilities over the classical energy range of about 4 to 20 keywith Si (111) crystals. For this reason, a design incorporating one rotation stage to drive both the first and second crystals was considered most promising. Separate rotary stages for the first and second crystals can sometimes provide more flexibility in their capacities to carry heavy loads (for heavily cooled first crystals or sagittal benders of second crystals), but their tuning capabilities were considered inferior to the single axis approach.

  10. Comparison of load parameters for stored materials

    DEFF Research Database (Denmark)

    Munch-Andersen, J.; Nielsen, J.

    1997-01-01

    that the wall friction measured in a silo might be significantly larger than the value obtained from shear tests. The load parameters depend on the load level, perhaps in a way not reflected by the internal friction angle. It is not necessarily on the safe side to determine the parameters for a high load level.......The load parameters listed in the european prestandard and those derived from the material tests conform reasonably well in many cases. There are, however, also many cases where the agreement is not satisfactory, especially due to larger variability of the measured values. This yields cretainly...... in several cases. The measurement of reliable and relevant wall friction coefficients is a severe problem. If the wall friction depends on if the normal load is increasing or decreasing, it is the value for increasing load which should be the relevant load parameter, but for coal and wheat it is seen...

  11. Loads in the design of flight vehicles

    Directory of Open Access Journals (Sweden)

    Simion TĂTARU

    2010-09-01

    Full Text Available The calculation of flight loads is a critical part of air vehicle design. On the other hand, the prediction of accurate loads is a sophisticated and complex process that requires skilled and experienced engineers. They must integrate results from wind tunnel tests, computer simulations, historical data and empirical formulations into a number of loads cases that provide a realistic assessment of the flight vehicle’s environment. Under these conditions, the vehicle must satisfy requirements imposed by regulatory agencies as part of the vehicle certification process.Loads and boundary conditions can be associated to either the finite element model or the underlying geometry. By associating loads and boundary conditions to the geometry the finite element model mesh and elements can be modified without redefining and applying the loads to the model. Loads and boundary conditions are associated to the model geometry by default.

  12. Effect of loading parameter on fretting fatigue

    Science.gov (United States)

    Kowser, Md. Arefin; Chowdhury, Mohammad Asaduzzaman; Shah, Quazi Md. Zobaer

    2017-06-01

    Fretting fatigue has become one of the major concern in the recent few decades since developed designs both structure's and complex engineering are facing with fatigue accompanied by friction. In this study, load factors as normal and bending forces influence on stress distribution along contact surface as well as fatigue life has been experimented by FEM analysis. Fatigue life is influenced prominently by variable fretting loads than variable tensile loadings. Maximum Von mises Stress and strain shows uniform horizontal straight line is found for maximum loading while for both type of bending, minimum loads yield the same character. It has been observed that stress distribution is more uniform for varying bending loads when variable fretting loads yield stress singularity nearer to the tip of contact between fretting pad and beam.

  13. Immediate non-occlusal loading vs. early loading in partially edentulous patients.

    Science.gov (United States)

    Testori, Tiziano; Bianchi, Francesca; Del Fabbro, Massimo; Szmukler-Moncler, Serge; Francetti, Luca; Weinstein, Roberto Ludovico

    2003-01-01

    Immediate loading of dental implants can reduce treatment time and management concerns, thus increasing patient acceptance. This paper reports the authors' preliminary experience with partially edentulous patients having received non-occlusally loaded provisional restorations within 24 hours of surgery, compared to patients treated according to an early loading protocol. The present data suggest that implant supported fixed partial prostheses can be immediately non-occlusally loaded and restored with a predictability similar to early loaded implants.

  14. Dynamic loading of galvanized parts

    Directory of Open Access Journals (Sweden)

    Michal Černý

    2010-01-01

    Full Text Available This work is divided into two parts: the theoretical part includes actual knowledge and points of view about degradation processes in construction materials, anticorrosion protection, zinc coat composition and high frequency fatigue. The laboratory part follow-up existing regulations contents Czech standards and formulate specifications for acquisition of objective information from acceleration la­bo­ra­to­ry tests in condensation chests, mechanical high frequency fatigue tests on pulsator machine and possibilities of evaluation of fatigue tests. Laboratory findings declare to fundamental types of damage of constructions with anticorrosion protection in real loading conditions with dynamic high frequency character. Laboratory tests were made in sulphide and chloride environments.

  15. Greywater pollution variability and loadings

    DEFF Research Database (Denmark)

    Eriksson, Eva; Andersen, Henrik Rasmus; Madsen, Toke S.

    2009-01-01

    was proved not to be readily degradable. Ammonium content, presumably from urine contamination, was found to undergo nitrification in the RBC. Mass flow (daily loads) for individual substances was calculated for several pollutants. Macropollutants were found to be generated in low numbers of grams per person......Small on-site greywater treatment and reuse plants are susceptible to high short-term variation in flow and pollutant concentrations. As demonstrated in this study of a bathroom greywater plant in Copenhagen, Denmark, the flow ranges from no-flow periods to high-flow periods reaching 34 l min−1....... Concentrations of both macro- and micro-pollutants (organic matter and parabens) were found to range by several orders of magnitude in the influent, based on sampling every 20 min. Paraben degradation was proven to occur in the rotating biological contactor (RBC), while the remnant organic matter in the effluent...

  16. Impaired sleep and allostatic load

    DEFF Research Database (Denmark)

    Clark, Alice Jessie; Dich, Nadya; Lange, Theis

    2014-01-01

    Objective: Understanding the mechanisms linking sleep impairment to morbidity and mortality is important for future prevention, but these mechanisms are far from elucidated. We aimed to determine the relation between impaired sleep, both in terms of duration and disturbed sleep, and allostatic load...... Biobank with comprehensive information on sleep duration, disturbed sleep, objective measures of an extensive range of biological risk markers, and physical conditions. Results: Long sleep (mean difference 0.23; 95% confidence interval, 0.13, 0.32) and disturbed sleep (0.14; 0.06, 0.22) were associated...... with higher AL as well as with high-risk levels of risk markers from the anthropometric, metabolic, and immune system. Sub-analyses suggested that the association between disturbed sleep and AL might be explained by underlying disorders. Whereas there was no association between short sleep and AL...

  17. Active load control using microtabs

    Science.gov (United States)

    Yen, Dora Te-Lun

    2001-11-01

    Micro-electro-mechanical (MEM) translational tabs are introduced for enhancing and controlling the aerodynamic loading on lifting surfaces. These microtabs are mounted near the trailing edge of lifting surfaces, retract and extend approximately normal to the surface and have a maximum deployment height on the order of the boundary-layer thickness. Deployment of the device effectively modifies the camber distribution of the lifting surface and hence, the lift generated. The effect of the microtabs on lift is shown to be as powerful as conventional control surfaces with lift changes of 30%--50% in the linear range of the lift curve using a tab with a height of 1% of airfoil chord placed at 5% of chord upstream of the trailing edge on the lower surface. A multi-disciplinary approach incorporating aspects of experimental and computational aerodynamics, mechanical design and microfabrication techniques has been taken to develop and test a "proof of concept" model. Flow simulations, using a Reynolds-averaged Navier Stokes solver, have been conducted to optimize the size and placement of the devices based on trailing edge volume constraints. Numerical and experimental wind tunnel results are in good agreement, and both confirm that these micro-scale devices create macro-scale changes in aerodynamic loading. Application of this rather simple but innovative lift control system based on microfabrication techniques introduces a robust, dynamic control device and will allow for the miniaturization of conventional high lift and control systems. The result is a significant reduction in typical control system weight, complexity and cost. Also due to the minute size of these tabs, their activation and response times are much faster than that of conventional trailing edge devices. The "proof of concept" tab design, fabrication techniques, computational and experimental setup, and test results using a representative airfoil are presented in this research. (For more information, see

  18. Load to Failure and Stiffness

    Science.gov (United States)

    Esquivel, Amanda O.; Duncan, Douglas D.; Dobrasevic, Nikola; Marsh, Stephanie M.; Lemos, Stephen E.

    2015-01-01

    Background: Rotator cuff tendinopathy is a frequent cause of shoulder pain that can lead to decreased strength and range of motion. Failures after using the single-row technique of rotator cuff repair have led to the development of the double-row technique, which is said to allow for more anatomical restoration of the footprint. Purpose: To compare 5 different types of suture patterns while maintaining equality in number of anchors. The hypothesis was that the Mason-Allen–crossed cruciform transosseous-equivalent technique is superior to other suture configurations while maintaining equality in suture limbs and anchors. Study Design: Controlled laboratory study. Methods: A total of 25 fresh-frozen cadaveric shoulders were randomized into 5 suture configuration groups: single-row repair with simple stitch technique; single-row repair with modified Mason-Allen technique; double-row Mason-Allen technique; double-row cross-bridge technique; and double-row suture bridge technique. Load and displacement were recorded at 100 Hz until failure. Stiffness and bone mineral density were also measured. Results: There was no significant difference in peak load at failure, stiffness, maximum displacement at failure, or mean bone mineral density among the 5 suture configuration groups (P sutures in the repair should be considered to judge the strength of the repair. Clinical Relevance: Previous in vitro studies have shown the double-row rotator cuff repair to be superior to the single-row repair; however, clinical research does not necessarily support this. This study found no difference when comparing 5 different repair methods, supporting research that suggests the number of sutures and not the pattern can affect biomechanical properties. PMID:26665053

  19. Allostatic load and biological anthropology.

    Science.gov (United States)

    Edes, Ashley N; Crews, Douglas E

    2017-01-01

    Multiple stressors affect developing and adult organisms, thereby partly structuring their phenotypes. Determining how stressors influence health, well-being, and longevity in human and nonhuman primate populations are major foci within biological anthropology. Although much effort has been devoted to examining responses to multiple environmental and sociocultural stressors, no holistic metric to measure stress-related physiological dysfunction has been widely applied within biological anthropology. Researchers from disciplines outside anthropology are using allostatic load indices (ALIs) to estimate such dysregulation and examine life-long outcomes of stressor exposures, including morbidity and mortality. Following allostasis theory, allostatic load represents accumulated physiological and somatic damage secondary to stressors and senescent processes experienced over the lifespan. ALIs estimate this wear-and-tear using a composite of biomarkers representing neuroendocrine, cardiovascular, metabolic, and immune systems. Across samples, ALIs are associated significantly with multiple individual characteristics (e.g., age, sex, education, DNA variation) of interest within biological anthropology. They also predict future outcomes, including aspects of life history variation (e.g., survival, lifespan), mental and physical health, morbidity and mortality, and likely health disparities between groups, by stressor exposures, ethnicity, occupations, and degree of departure from local indigenous life ways and integration into external and commodified ones. ALIs also may be applied to similar stress-related research areas among nonhuman primates. Given the reports from multiple research endeavors, here we propose ALIs may be useful for assessing stressors, stress responses, and stress-related dysfunction, current and long-term cognitive function, health and well-being, and risk of early mortality across many research programs within biological anthropology. © 2017 American

  20. Load research manual. Volume 2. Fundamentals of implementing load research procedures

    Energy Technology Data Exchange (ETDEWEB)

    Brandenburg, L.; Clarkson, G.; Grund, Jr., C.; Leo, J.; Asbury, J.; Brandon-Brown, F.; Derderian, H.; Mueller, R.; Swaroop, R.

    1980-11-01

    This three-volume manual presents technical guidelines for electric utility load research. Special attention is given to issues raised by the load data reporting requirements of the Public Utility Regulatory Policies Act of 1978 and to problems faced by smaller utilities that are initiating load research programs. In Volumes 1 and 2, procedures are suggested for determining data requirements for load research, establishing the size and customer composition of a load survey sample, selecting and using equipment to record customer electricity usage, processing data tapes from the recording equipment, and analyzing the data. Statistical techniques used in customer sampling are discussed in detail. The costs of load research also are estimated, and ongoing load research programs at three utilities are described. The manual includes guides to load research literature and glossaries of load research and statistical terms.

  1. Multi-Capacity Load Cell Concept

    Directory of Open Access Journals (Sweden)

    Seif. M. OSMAN

    2014-09-01

    Full Text Available Force measuring systems are usually used to calibrate force generated systems, it is not preferable to use load cells to measure forces less than 10 % of its nominal capacity. Several load cells are required to offer calibration facilities at sites to cover different ranges, this lead to difficulties in handling procedures, through the need for several carrying cases to carry this overweight in addition to the over cost of purchasing several load cells. This article concerns with introducing a new concept for designing a multi-capacity load cell as a new force standard in the field of measuring the force. This multi-capacity load cell will replace a set of load cells and reflects economically on the total cost and on easiness of handling procedures.

  2. Static Load Distribution in Ball Bearings

    Science.gov (United States)

    Ricci, Mario

    2010-01-01

    A numerical procedure for computing the internal loading distribution in statically loaded, single-row, angular-contact ball bearings when subjected to a known combined radial and thrust load is presented. The combined radial and thrust load must be applied in order to avoid tilting between inner and outer rings. The numerical procedure requires the iterative solution of Z + 2 simultaneous nonlinear equations - where Z is the number of the balls - to yield an exact solution for axial and radial deflections, and contact angles. Numerical results for a 218 angular-contact ball bearing have been compared with those from the literature and show significant differences in the magnitudes of the ball loads, contact angles, and the extent of the loading zone.

  3. 1991 Pacific Northwest Loads and Resources Study.

    Energy Technology Data Exchange (ETDEWEB)

    United States. Bonneville Power Administration.

    1991-12-01

    This study establishes the Bonneville Power Administration's (BPA) planning basis for supplying electricity to BPA customers. The Loads and Resources Study is presented in three documents: (1) this summary of federal system and Pacific Northwest region loads and resources; (2) a technical appendix detailing forecasted Pacific Northwest economic trends and loads, and (3) a technical appendix detailing the loads and resources for each major Pacific Northwest generating utility. This analysis updates our 1990 study. BPS's long-range planning incorporates resource availability with a range of forecasted electrical consumption. The forecasted future electrical demands-firm loads--are subtracted from the projected capability of existing resources to determine whether BPA and the region will be surplus or deficit. If resources are greater than loads in any particular year or month, there is a surplus of energy and/or capacity, which BPA can sell to increase revenues. Conversely, if firm loads exceed available resources, there is a deficit of energy and/or capacity, then additional conservation, contract purchases, or generating resources will be needed to meet load growth. This study analyzes the Pacific Northwest's projected loads and available generating resources in two parts: (1) the loads and resources of the federal system, for which BPA is the marketing agency; and (2) the larger Pacific Northwest regional profile, which includes loads and resources in addition to the federal system. This study presents the federal system and regional analyses for five load forecasts: high, medium-high, medium, medium-low, and low. This analysis projects the yearly average energy consumption and resource availability for 1992- 2012.

  4. Loads in the design of flight vehicles

    OpenAIRE

    Simion TĂTARU; Radu BÎSCĂ; Dorin LOZICI-BRÎNZEI

    2010-01-01

    The calculation of flight loads is a critical part of air vehicle design. On the other hand, the prediction of accurate loads is a sophisticated and complex process that requires skilled and experienced engineers. They must integrate results from wind tunnel tests, computer simulations, historical data and empirical formulations into a number of loads cases that provide a realistic assessment of the flight vehicle’s environment. Under these conditions, the vehicle must satisfy requirements im...

  5. Cyclic Triaxial Loading of Cohesionless Silty Sand

    DEFF Research Database (Denmark)

    Sabaliauskas, Tomas; Ibsen, Lars Bo

    2015-01-01

    To engineer efficient structures offshore, we need to extend our knowledge of soil response. Cyclic loading and high water pressure encountered offshore greatly influence cohesionless soil performance. Silty sand from Frederikshavn wind turbine farm was tested using single diameter height samples...... with lubricated, smooth boundary piston heads in a Danish triaxial apparatus. Samples were successfully subjected to loading histories of high complexity. Loading include high strains and stresses, post liquefaction response, transitioning through multiple densities and restoring initial soil properties after...

  6. Fatigue durability under random cyclic loading

    Science.gov (United States)

    Volkov, S. S.; Struzhanov, V. V.

    2017-12-01

    Methods for predicting the durability of metals have been developed while taking into account the effect of random loads acting during the service life of structures. Methods of the theory of functions of random variables are applied. Normal distribution and the Rayleigh distribution are used to estimate the random loads from the experimental histogram. A numerical example illustrates the influence of the statistical parameters of the load distribution on the predicted number of cycles before failure.

  7. Valproic acid loading during intensive monitoring.

    Science.gov (United States)

    Rosenfeld, W E; Leppik, I E; Gates, J R; Mireles, R E

    1987-07-01

    Of 35 patients who had generalized tonic-clonic seizures during antiepileptic drug therapy withdrawal, "loading" with valproic acid was effective in limiting these seizures in 32 patients. A loading dose of approximately 12.5 mg/kg was used. This dose resulted in valproic acid levels between 284 and 458 mumol/L (41 and 66 mg/L) 1.5 hours after "loading" in six of the eight patients in whom serum concentrations were measured.

  8. Timber joints under long-term loading

    DEFF Research Database (Denmark)

    Feldborg, T.; Johansen, M.

    This report describes tests and results from stiffness and strength testing of splice joints under long-term loading. During two years of loading the spicimens were exposed to cyclically changing relative humidity. After the loading period the specimens were short-term tested. The connectors were...... integral nail-plates and nailed steel and plywood gussets. The report is intended for designers and researchers in timber engineering....

  9. The load intesity of florbal players

    OpenAIRE

    Niklas, Martin

    2012-01-01

    Title: The load intensity of floorball players. Objectives: The aim of the work is to compare the load intensity of floorball players in training unit and in competitive match. Methods: To measure the intensity of loading was selected set of floorbal players from extraleague team. Then was performed their measuring heart rate by sport testers in the training unit and in the competitive match. Results: The results of measurement showed a higher average and maximum heart rate of players during ...

  10. Assessment of wind turbine load measurement instrumentation

    Energy Technology Data Exchange (ETDEWEB)

    Morfiadakis, E.; Papadopoulos, K. [CRES (Greece); Borg, N. van der [ECN, Petten (Netherlands); Petersen, S.M. [Risoe, Roskilde (Denmark); Seifert, H. [DEWI, Wilhelmshaven (Germany)

    1999-03-01

    In the framework of Sub-Task3 `Wind turbine load measurement instrumentation` of EU-project `European Wind Turbine Testing Procedure Development`, the load measurement techniques have been assessed by laboratory, full scale and numerical tests. The existing methods have been reviewed with emphasis on the strain gage application techniques on composite materials and recommendations are provided for the optimisation of load measurement techniques. (au) EU. 14 refs.

  11. Load relaxation studies of zircaloy-4

    Energy Technology Data Exchange (ETDEWEB)

    Huang, F.H.; Sabol, G.P.; McDonald, S.G.; Li, C.Y.

    1976-01-01

    The results of the present work have shown (1) the load relaxation data of Zircaloy-4 in the temperature range of 200/sup 0/C to 385/sup 0/C can be represented by the phenomenological model based on Hart's plastic equation of state; (2) the room temperature load relaxation data reflect the effects of deformation twinning; (3) at higher temperatures the load relaxation data suggest the contribution of grain boundary sliding; and (4) the effects of strain aging can be identified based on the load relaxation data.

  12. Behaviour of Cohesionless Soils During Cyclic Loading

    DEFF Research Database (Denmark)

    Shajarati, Amir; Sørensen, Kris Wessel; Nielsen, Søren Kjær

    Offshore wind turbine foundations are typically subjected to cyclic loading from both wind and waves, which can lead to unacceptable deformations in the soil. However, no generally accepted standardised method is currently available, when accounting for cyclic loading during the design of offshore...... wind turbine foundations. Therefore a literature study is performed in order to investigate existing research treating the behaviour of cohesionless soils, when subjected to cyclic loading. The behaviour of a soil subjected to cyclic loading is found to be dependent on; the relative density, mean...

  13. Load prediction of stall regulated wind turbines

    Energy Technology Data Exchange (ETDEWEB)

    Bjoerck, A.; Dahlberg, J.Aa. [Aeronautical Research Inst. of Sweden, Bromma (Sweden); Carlen, I. [Chalmers Univ. of Technology, Goeteborg (Sweden). Div. of Marine Structural Engineering; Ganander, H. [Teknikgruppen AB, Sollentua (Sweden)

    1996-12-01

    Measurements of blade loads on a turbine situated in a small wind farm shows that the highest blade loads occur during operation close to the peak power i.e. when the turbine operates in the stall region. In this study the extensive experimental data base has been utilised to compare loads in selected campaigns with corresponding load predictions. The predictions are based on time domain simulations of the wind turbine structure, performed by the aeroelastic code VIDYN. In the calculations a model were adopted in order to include the effects of dynamic stall. This paper describes the work carried out so far within the project and key results. 5 refs, 10 figs

  14. Comparison of Temperature Loadings of Bridge Girders

    Directory of Open Access Journals (Sweden)

    J. Římal

    2008-01-01

    Full Text Available This paper compares the effect of temperature changes on the superstructure of bridges, above all the effect of non-uniform temperature. Loadings according to standards ESN 73 6203, ENV 1991-1-5 and DIN 1072 are compared here. The paper shows a short summary of temperature loading according to each standard and shows the comparison of bending moments arisen from these temperature loadings on superstructure made from continuous girder from a steel-concrete box girder with a composite concrete slab. With respect to a variety of design processes, the comparison is made without any coefficient of loading, combination or material. 

  15. Safety Harness For Work Under Suspended Load

    Science.gov (United States)

    Sunoo, Su Young

    1994-01-01

    Safety device protects worker under suspended engine or other heavy load. Mechanically linked with load so if load should fall, worker yanked safely away. Worker wears chest-plate vest with straps crossing eye on back. Lower safety cable connected to eye extends horizontally away from worker to nearby wall, wrapped on pulley and extends upward to motion amplifier or reducer. Safety cables transform any sudden downward motion of overhanging load into rapid sideways motion of worker. Net catches worker, preventing worker from bumping against wall.

  16. System and method employing a self-organizing map load feature database to identify electric load types of different electric loads

    Science.gov (United States)

    Lu, Bin; Harley, Ronald G.; Du, Liang; Yang, Yi; Sharma, Santosh K.; Zambare, Prachi; Madane, Mayura A.

    2014-06-17

    A method identifies electric load types of a plurality of different electric loads. The method includes providing a self-organizing map load feature database of a plurality of different electric load types and a plurality of neurons, each of the load types corresponding to a number of the neurons; employing a weight vector for each of the neurons; sensing a voltage signal and a current signal for each of the loads; determining a load feature vector including at least four different load features from the sensed voltage signal and the sensed current signal for a corresponding one of the loads; and identifying by a processor one of the load types by relating the load feature vector to the neurons of the database by identifying the weight vector of one of the neurons corresponding to the one of the load types that is a minimal distance to the load feature vector.

  17. Measuring training load in sports.

    Science.gov (United States)

    Lambert, Michael Ian; Borresen, Jill

    2010-09-01

    The principle of training can be reduced to a simple "dose-response" relationship. The "response" in this relationship can be measured as a change in performance or the adaptation of a physiological system. The "dose" of training, or physiological stress associated with the training load, is more difficult to measure as there is no absolute "gold standard" which can be used in the field, making it difficult to validate procedures. Attempts have been made to use heart rate as a marker of intensity during training, but the theoretical attractiveness of this method is not supported by the accuracy and the practicality of using this method during training or competition. The session RPE, based on the product of training duration and perceived intensity is more practical and can be used in a variety of sports. However, the score depends on a subjective assessment, and the intersubject comparisons may be inaccurate. The demands of different sports vary and therefore the methods of assessing training need to vary accordingly. The time has come to reach consensus on assessing training accurately in different sports. There is a precedent for this consensus approach with scientists having already done so for the assessment of physical activity, and for defining injuries in rugby, football and cricket. Standardizing these methods has resulted in the quality of research in these areas increasing exponentially.

  18. Wind loading on solar collectors

    Energy Technology Data Exchange (ETDEWEB)

    Bhaduri, S.; Murphy, L.M.

    1985-06-01

    The present design methodology for the determination of wind loading on the various solar collectors has been reviewed and assessed. The total force coefficients of flat plates of aspect ratios 1.0 and 3.0, respectively, at various angles of attack obtained by using the guidelines of the ANSI A58.1-1982, have been compared with those obtained by using the methodology of the ASCE Task Committee, 1961, and the experimental results of the full-scale test of heliostats by Peglow. The turbulent energy spectra, currently employed in the building code, are compared with those of Kaimal et al., Lumley, and Ponofsky for wind velocities of 20.0 m/s and 40.24 m/s at an elevation of 9.15 m. The longitudinal spectra of the building code overestimates the Kaimal spectra in the frequency range of 0.007 Hz to 0.08 Hz and underestimates beyond the frequency of 0.08 Hz. The peak angles of attack, on the heliostat, stowed in horizontal position, due to turbulent vertical and lateral components of wind velocity, have been estimated by using Daniel's methodology for three wind velocities and compared with the value suggested by the code. The experimental results of a simple test in the laboratory indicate the feasibility of decreasing the drag forces of the flat plate by reducing the solidity ratio.

  19. Procedures for Calculating Residential Dehumidification Loads

    Energy Technology Data Exchange (ETDEWEB)

    Winkler, Jon [National Renewable Energy Lab. (NREL), Golden, CO (United States); Booten, Chuck [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2016-06-01

    Residential building codes and voluntary labeling programs are continually increasing the energy efficiency requirements of residential buildings. Improving a building's thermal enclosure and installing energy-efficient appliances and lighting can result in significant reductions in sensible cooling loads leading to smaller air conditioners and shorter cooling seasons. However due to fresh air ventilation requirements and internal gains, latent cooling loads are not reduced by the same proportion. Thus, it's becoming more challenging for conventional cooling equipment to control indoor humidity at part-load cooling conditions and using conventional cooling equipment in a non-conventional building poses the potential risk of high indoor humidity. The objective of this project was to investigate the impact the chosen design condition has on the calculated part-load cooling moisture load, and compare calculated moisture loads and the required dehumidification capacity to whole-building simulations. Procedures for sizing whole-house supplemental dehumidification equipment have yet to be formalized; however minor modifications to current Air-Conditioner Contractors of America (ACCA) Manual J load calculation procedures are appropriate for calculating residential part-load cooling moisture loads. Though ASHRAE 1% DP design conditions are commonly used to determine the dehumidification requirements for commercial buildings, an appropriate DP design condition for residential buildings has not been investigated. Two methods for sizing supplemental dehumidification equipment were developed and tested. The first method closely followed Manual J cooling load calculations; whereas the second method made more conservative assumptions impacting both sensible and latent loads.

  20. Mechanical behavior of cyclically loaded PZT

    Energy Technology Data Exchange (ETDEWEB)

    White, G.S.; Hill, M.D.; Freiman, S.W. [National Inst. of Standards and Technology, Gaithersburg, MD (United States); Hwang, C.S. [Seoul National Univ. (Korea, Republic of)

    1994-12-31

    Uses of intelligent materials which involve the application of force or the generation of displacements will require the incorporation of some form of actuator material into the overall structure. Typically, these types of applications will result in the generation of cyclic loads on the actuator; depending upon the specific application, the frequency of the loading could be low, e.g., for positioning components, or relatively high, e.g., for damping out vibrations in machining tools. Nevertheless, the cyclic nature of the loading raises the specter of damage and, ultimately, failure arising from cyclic loading processes which would not be predicted by traditional mechanical properties test methods. It has been found that PZT loaded cyclically sometimes fails at loads below its nominal strength, as measured by traditional, monotonically increasing load tests. Damage mechanisms which come into play as a result of the cyclic loading conditions have been postulated as the reasons for this behavior. Recent work investigating the cyclic loading of a PZT-8 material at resonance frequency determined that microcracks were generated in the high stress region of the material. Recent results demonstrate that macrocrack extension appears to be accompanied by domain reorientation whereas microcracks can propagate around PZT grains without affecting the domains, (2) morphology and distribution of microcracks generated under different loading conditions can change dramatically that the qualitative mechanical response of PZT-8 to cyclic loading appears to be insensitive to grain morphology. The results presented imply that stresses generated at the tips of macrocracks are much larger than those at microcracks, that temperature strongly affects the rate of microcrack generation, and that wide distributions in grain size and the presence of large voids do not necessarily result in increased microcrack generation over that seen in 2 {micro}m grain size, small pore material.

  1. Behaviour of glass plates under wind loads

    Science.gov (United States)

    Gavanski, Eri

    Glazing damage during strong windstorms has been considered to result mainly from windborne debris. However, recent windstorm damage reports have revealed the necessity of studying fluctuating wind loads, which appear to be another factor contributing to this damage. From an experimental point of view, studies on this topic have been limited to the application of rather simple loading patterns. Moreover, there is an uncertainty surrounding both load resistance and design load used in the current North American window glass design codes. It is of concern that these regulations may not offer sufficient accuracy on account of the limited understanding of time-dependent glass strength derived from the technology available at the time of codification. Unprecedented full-scale glass breakage tests under realistic wind pressure loading were conducted to investigate these issues. The obtained results revealed significant new information about the behavior of glass plates under fluctuating loads. Along with these tests, a numerical simulation using the Monte-Carlo technique was also performed with a subtle modification of the initial glass strength. This adjustment resulted in better correspondence with test results. Using the test and numerical simulation results, the current window glass design method was examined. The calculation methods of LR, and the reference time conversion used in the codes, were found to require further investigation. By creating a particular wind pressure time history, the practice of using peak pressures from ASCE7-05 as the design load was investigated. The results showed that there are cases when the current practice may underestimate the design load because of the duration of windstorms. KEYWORDS: Glass, Fluctuating load, Full-scale test, Load resistance, Design load, Static fatigue, Numerical simulation, Monte-Carlo technique, Brown's integral.

  2. Demonstration of load rating capabilities through physical load testing : Johnson County bridge case study.

    Science.gov (United States)

    2013-08-01

    The objective of this work, Pilot Project - Demonstration of Capabilities and Benefits of Bridge Load Rating through Physical Testing, was to demonstrate the capabilities for load testing and rating bridges in Iowa, study the economic benefit of perf...

  3. Demonstration of load rating capabilities through physical load testing : Sioux County bridge case study.

    Science.gov (United States)

    2013-08-01

    The objective of this work, Pilot Project - Demonstration of Capabilities and Benefits of Bridge Load Rating through Physical Testing, was to demonstrate the capabilities for load testing and rating bridges in Iowa, study the economic benefit of perf...

  4. Demonstration of load rating capabilities through physical load testing : Ida County bridge case study.

    Science.gov (United States)

    2013-08-01

    The objective of this work, Pilot Project - Demonstration of Capabilities and Benefits of Bridge Load Rating through Physical Testing, was to demonstrate the capabilities for load testing and rating bridges in Iowa, study the economic benefit of perf...

  5. Definition of a Comprehensive Loads Process in the DLR Project iLOADS

    OpenAIRE

    Krüger, Wolf R.; Klimmek, Thomas

    2016-01-01

    The determination of loads acting on the aircraft is one of the main tasks during aircraft development. The knowledge of loads is important for aircraft design, e.g. for the sizing of the airframe structure, and also for certification. The definition of realistic loads assumptions is important, as well as the generation of loads from simulation and experiment. DLR is involved in a large number of aircraft design activities, and operates a fleet of research aircraft; thus DLR requires in-depth...

  6. Strategies for Controlling Plug Loads. A Tool for Reducing Plug Loads in Commercial Buildings

    Energy Technology Data Exchange (ETDEWEB)

    Torcellini, Paul [National Renewable Energy Lab. (NREL), Golden, CO (United States); Bonnema, Eric [National Renewable Energy Lab. (NREL), Golden, CO (United States); Sheppy, Michael [National Renewable Energy Lab. (NREL), Golden, CO (United States); Pless, Shanti [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2015-09-01

    Plug loads are often not considered as part of the energy savings measures in Commercial Buildings; however, they can account for up to 50% of the energy used in the building. These loads are numerous and often scattered throughout a building. Some of these loads are purchased by the owner and some designed into the building or the tenant finishes for a space. This document provides a strategy and a tool for minimizing these loads.

  7. Load power device and system for real-time execution of hierarchical load identification algorithms

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Yi; Madane, Mayura Arun; Zambare, Prachi Suresh

    2017-11-14

    A load power device includes a power input; at least one power output for at least one load; and a plurality of sensors structured to sense voltage and current at the at least one power output. A processor is structured to provide real-time execution of: (a) a plurality of load identification algorithms, and (b) event detection and operating mode detection for the at least one load.

  8. Comparison of the loading rate in various types of swimming with load.

    OpenAIRE

    Pospíšek, Tomáš

    2013-01-01

    Title of work Comparison of the loading rate in various types of swimming with load. Work objective Comparison of physical intensity in selected types of swimming with load used in the ACR. The level of physical intensity was determined on the basis of measured heart rate at different styles of swimming with load. Used methods The method used in this work was quantitative research with the observation of how the organism responds to the stress. There were 4 people tested. The measurement was ...

  9. Reducing the Cognitive Load on Novice Programmers.

    Science.gov (United States)

    Garner, Stuart

    Computer programming is a domain of knowledge that is generally considered difficult by students, many of whom experience low levels of achievement and become disillusioned. This paper suggests that cognitive load theory needs to be taken into account when designing instructional materials for this domain. The cognitive load that is experienced by…

  10. A case study of micromachined load cell

    Indian Academy of Sciences (India)

    silicon dioxide grown on a silicon substrate. When the load is applied, the sensing element deforms and causes the change in resistance due to stresses and the piezo-resistive property change. The proposed layout of the sensing element to be used in the load cell is shown in figure 1. All the four gauges are deposited on ...

  11. Controllable Load Management Approaches in Smart Grids

    Directory of Open Access Journals (Sweden)

    Jingshuang Shen

    2015-10-01

    Full Text Available With rapid smart grid technology development, the customer can actively participate in demand-side management (DSM with the mutual information communication between the distributor operation company and the smart devices in real-time. Controllable load management not only has the advantage of peak shaving, load balance, frequency regulation, and voltage stability, but is also effective at providing fast balancing services to the renewable energy grid in the distributed power system. The load management faces an enormous challenge as the customer has a large number of both small residential loads and dispersed renewable sources. In this paper, various controllable load management approaches are discussed. The traditional controllable load approaches such as the end users’ controllable appliances, storage battery, Vehicle-to-Grid (V2G, and heat storage are reviewed. The “broad controllable loads” management, such as the microgrid, Virtual Power Plant (VPP, and the load aggregator are also presented. Furthermore, the load characteristics, control strategies, and control effectiveness are analyzed.

  12. Load-Bearing Capacity of Roof Trusses

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard; Damkilde, Lars; Munch-Andersen, J.

    2004-01-01

    systems such as roof trusses are established and statistical characteristics of the load bearing capacity are determined. The results show that there is a significant increase in the characteristic (nominal) value and a reduction in the coefficient of variation (COV) for typical loads such as permanent...

  13. Cell Load Balancing in Heterogeneous Scenarios

    DEFF Research Database (Denmark)

    Eduardo, Simao; Rodrigues, Antonio; Mihovska, Albena D.

    2013-01-01

    Cell load imbalances in wireless networks degrade performance. Macro and small cell collocated deployments (heterogeneous scenario) constitutes a new problem for load balancing. This paper proposes a novel admission control algorithm for an optimal solution to the assignment of traffic flows...

  14. Modelling and Simulation of Wave Loads

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard; Thoft-Christensen, Palle

    1985-01-01

    A simple model of the wave load on stender members of offshore structures is described . The wave elevation of the sea stateis modelled by a stationary Gaussian process. A new procedure to simulate realizations of the wave loads is developed. The simulation method assumes that the wave particle...

  15. Using Electroencephalography to Measure Cognitive Load

    Science.gov (United States)

    Antonenko, Pavlo; Paas, Fred; Grabner, Roland; van Gog, Tamara

    2010-01-01

    Application of physiological methods, in particular electroencephalography (EEG), offers new and promising approaches to educational psychology research. EEG is identified as a physiological index that can serve as an online, continuous measure of cognitive load detecting subtle fluctuations in instantaneous load, which can help explain effects of…

  16. Fruit load governs transpiration of olive trees

    NARCIS (Netherlands)

    Bustan, Amnon; Dag, Arnon; Yermiyahu, Uri; Erel, Ran; Presnov, Eugene; Agam, Nurit; Kool, Dilia; Iwema, Joost; Zipori, Isaac; Ben-Gal, Alon

    2016-01-01

    We tested the hypothesis that whole-tree water consumption of olives (Olea europaea L.) is fruit load-dependent and investigated the driving physiological mechanisms. Fruit load was manipulated in mature olives grown in weighing-drainage lysimeters. Fruit was thinned or entirely removed from

  17. Baseline axle load survey in Malawi - 2014

    CSIR Research Space (South Africa)

    Roux, M

    2015-07-01

    Full Text Available As part of the project to update the Malawian Directorate of Road Transport and Safety Services’ (DRTSS) 2005 Axle Load Control Strategy and to provide a five-year implementation plan, a country-wide axle load survey was undertaken to assess...

  18. Concrete structures under impact loading rate effects

    NARCIS (Netherlands)

    Zielinski, A.J.

    1984-01-01

    Various structures may be subjected to accidental, impact loading. The behaviour of structures under that kind of extreme loading conditions is of vital importance for people's safety and environmental damage prevention. There is a need for reliable assessment methods for the local and the overall

  19. Critical loads of heavy metals for soils

    NARCIS (Netherlands)

    Vries, de W.; Groenenberg, J.E.; Lofts, S.; Tipping, E.; Posch, M.

    2012-01-01

    To enable a precautionary risk assessment for future inputs of metals, steady-state methods have been developed to assess critical loads of metals avoiding long-term risks to food quality and eco-toxicological effects on organisms in soils and surface waters. A critical load for metals equals the

  20. Identification of dynamic load for prosthetic structures.

    Science.gov (United States)

    Zhang, Dequan; Han, Xu; Zhang, Zhongpu; Liu, Jie; Jiang, Chao; Yoda, Nobuhiro; Meng, Xianghua; Li, Qing

    2017-12-01

    Dynamic load exists in numerous biomechanical systems, and its identification signifies a critical issue for characterizing dynamic behaviors and studying biomechanical consequence of the systems. This study aims to identify dynamic load in the dental prosthetic structures, namely, 3-unit implant-supported fixed partial denture (I-FPD) and teeth-supported fixed partial denture. The 3-dimensional finite element models were constructed through specific patient's computerized tomography images. A forward algorithm and regularization technique were developed for identifying dynamic load. To verify the effectiveness of the identification method proposed, the I-FPD and teeth-supported fixed partial denture structures were investigated to determine the dynamic loads. For validating the results of inverse identification, an experimental force-measuring system was developed by using a 3-dimensional piezoelectric transducer to measure the dynamic load in the I-FPD structure in vivo. The computationally identified loads were presented with different noise levels to determine their influence on the identification accuracy. The errors between the measured load and identified counterpart were calculated for evaluating the practical applicability of the proposed procedure in biomechanical engineering. This study is expected to serve as a demonstrative role in identifying dynamic loading in biomedical systems, where a direct in vivo measurement may be rather demanding in some areas of interest clinically. Copyright © 2017 John Wiley & Sons, Ltd.

  1. Load Extrapolation During Operation for Wind Turbines

    DEFF Research Database (Denmark)

    Toft, Henrik Stensgaard; Sørensen, John Dalsgaard

    2008-01-01

    In the recent years load extrapolation for wind turbines has been widely considered in the wind turbine industry. Loads on wind turbines during operations are normally dependent on the mean wind speed, the turbulence intensity and the type and settings of the control system. All these parameters...

  2. 14 CFR 23.427 - Unsymmetrical loads.

    Science.gov (United States)

    2010-01-01

    ... Balancing Surfaces § 23.427 Unsymmetrical loads. (a) Horizontal surfaces other than main wing and their..., wings, horizontal surfaces other than main wing, and fuselage shape: (1) 100 percent of the maximum loading from the symmetrical flight conditions may be assumed on the surface on one side of the plane of...

  3. Multi-Capacity Load Cell Concept

    National Research Council Canada - National Science Library

    Seif M Osman; Ebtisam H Hasan; H M El-Hakeem; R M Rashad; F Kouta

    2014-01-01

    ... to carry this overweight in addition to the over cost of purchasing several load cells. This article concerns with introducing a new concept for designing a multi-capacity load cell as a new force standard in the field of measuring the force...

  4. Traffic load effects in prestrssed concrete bridges

    NARCIS (Netherlands)

    Vrouwenvelder, A.C.W.M.; Allaix, D.L.; Courage, W.M.G.

    2007-01-01

    The traffic load effect of a two-span prestressed concrete bridge with two traffic lanes is analyzed in this paper. The design value of the result-ing bending moment in some prescribed sections is estimated by means of a Monte Carlo simulation. The model for the vehicular loads is derived from a set

  5. Macrophyte Community Response to Nitrogen Loading and ...

    Science.gov (United States)

    Empirical determination of nutrient loading thresholds that negatively impact seagrass communities have been elusive due to the multitude of factors involved. Using a mesocosm system that simulated Pacific Northwest estuaries, we evaluated macrophyte metrics across gradients of NO3 loading (0, 1.5, 3 and 6x ambient) and temperature (10 and 20 °C). Macroalgal growth, biomass, and C:N responded positively to increased NO3 load and floating algal mats developed at 20 ºC. Zostera japonica metrics, including C:N, responded more to temperature than to NO3 loading. Z. marina biomass exhibited a negative temperature effect and in some cases a negative NO3 effect, while growth rate increased with temperature. Shoot survival decreased at 20 ºC but was not influenced by NO3 loading. Wasting disease index exhibited a significant temperature by NO3 interaction consistent with increased disease susceptibility. Community shifts observed were consistent with the nutrient loading hypothesis at 20 ºC, but there was no evidence of other eutrophication symptoms due to the short residence time. The Nutrient Pollution Index tracked the NO3 gradient at 10 ºC but exhibited no response at 20 ºC. We suggest that systems characterized by cool temperatures, high NO3 loads, and short residence time may be resilient to many symptoms of eutrophication. Estuarine systems characterized by cool temperatures, high nutrient loads and rapid flushing may be resilient to some symptoms

  6. Duration of load effects of solid wood

    DEFF Research Database (Denmark)

    Svensson, Staffan

    Test methods for studying the effect of long-term loading on the load carrying capacity of structural wood are discussed. The impact of sampling procedures on test results is investigated and is exemplified. It is concluded from this investigation that the sampling method has a significant impact...

  7. Suction caissons subjected to monotonic combined loading

    DEFF Research Database (Denmark)

    Penzes, P.; Jensen, M.R.; Zania, Varvara

    2016-01-01

    for offshore wind turbines. The combined loading imposed typically to a suction caisson has led to the estimation of their bearing capacity by means of 3D failure envelopes. This study aims to analyse the behaviour of suction caissons for offshore wind turbines subjected to combined loading. Finite element...

  8. Simulating liquid loading in gas wells

    NARCIS (Netherlands)

    Schiferli, W.; Belfroid, S.P.C.; Savenko, S.; Veeken, C.A.M.; Hu, B.

    2010-01-01

    This paper describes work performed by the authors over the last several years to better understand the factors affecting the onset of liquid loading. To further improve the prediction of onset of liquid loading, efforts were undertaken to better model the process. Dedicated codes as well as a

  9. Damage Accumulation in Vertical Breakwaters due to Combined Impact Loading and Pulsating Wave Loads

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard; Nielsen, Søren R. K.

    1999-01-01

    Vertical wall breakwaters used to protect for example an harbour from large waves usually consist of large concrete caissons placed on the seabed. The wave loads can be divided in two types, pulsating and impact loads. For some types of breakwaters especially the impact wave loads can be very large...

  10. on the correctness of load loss factor correctness of load loss factor ...

    African Journals Online (AJOL)

    eobe

    Author Tel: +44 -753-526-7242. TECHNICAL NOTE: TECHNICAL NOTE: ON THE CORRECTNESS OF LOAD LOSS FACTOR. CORRECTNESS OF LOAD LOSS FACTOR. CORRECTNESS OF LOAD LOSS FACTOR. A. O. Ekwue*. JACOBS ENGINEERING INC/BRUNEL UNIVERSITY LONDON,UNITED KINGDOM.

  11. 14 CFR 29.511 - Ground load: unsymmetrical loads on multiple-wheel units.

    Science.gov (United States)

    2010-01-01

    ... multiple-wheel units. 29.511 Section 29.511 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION... Requirements Ground Loads § 29.511 Ground load: unsymmetrical loads on multiple-wheel units. (a) In dual-wheel gear units, 60 percent of the total ground reaction for the gear unit must be applied to one wheel and...

  12. Modelling of Generic Slung Load System

    DEFF Research Database (Denmark)

    Bisgaard, Morten; Bendtsen, Jan Dimon; La Cour-Harbo, Anders

    2006-01-01

    This paper presents the result of modelling and verification of a generic slung load system using a small-scale helicopter. The model is intended for use in simulation, pilot training, estimation, and control. The model is derived using a redundant coordinate formulation based on Gauss Principle...... of Least Constraint using the Udwadia-Kalaba equation and can be used to model all body to body slung load suspension types. The model gives an intuitive and easy-to-use way of modelling and simulating di erent slung load suspension types and it includes detection and response of wire slacking...... and tightening, and aerodynamical coupling between the helicopter and the load. Furthermore, it is shown how the model can be easily used for multi-lift systems either with multiple helicopers or multiple loads. A numerical stabilisation algorithm as well as a trim algorithm is presented for the complete...

  13. Modeling of Generic Slung Load System

    DEFF Research Database (Denmark)

    Bisgaard, Morten; Bendtsen, Jan Dimon; la Cour-Harbo, Anders

    2009-01-01

    This paper presents the result of the modelling and verification of a generic slung load system using a small-scale helicopter. The model is intended for use in simulation, pilot training, estimation, and control. The model is derived using a redundant coordinate formulation based on Gauss......' Principle of Least Constraint using the Udwadia-Kalaba equation and can be used to model all body to body slung load suspension types. The model provides intuitive and easy-to-use means of modelling and simulating different slung load suspension types. It includes detection of, and response to, wire...... slackening and tightening as well as aerodynamic coupling between the helicopter and the load. Furthermore, it is shown how the model can be easily used for multi-lift systems either with multiple helicopters or multiple loads. A numerical stabilisation algorithm is introduced and finally the use...

  14. A methodology for Electric Power Load Forecasting

    Directory of Open Access Journals (Sweden)

    Eisa Almeshaiei

    2011-06-01

    Full Text Available Electricity demand forecasting is a central and integral process for planning periodical operations and facility expansion in the electricity sector. Demand pattern is almost very complex due to the deregulation of energy markets. Therefore, finding an appropriate forecasting model for a specific electricity network is not an easy task. Although many forecasting methods were developed, none can be generalized for all demand patterns. Therefore, this paper presents a pragmatic methodology that can be used as a guide to construct Electric Power Load Forecasting models. This methodology is mainly based on decomposition and segmentation of the load time series. Several statistical analyses are involved to study the load features and forecasting precision such as moving average and probability plots of load noise. Real daily load data from Kuwaiti electric network are used as a case study. Some results are reported to guide forecasting future needs of this network.

  15. Simulation of Stochastic Loads for Fatigue Experiments

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard; Brincker, Rune

    1989-01-01

    A simple direct simulation method for stochastic fatigue-load generation is described in this paper. The simulation method is based on the assumption that only the peaks of the load process significantly affect the fatigue life. The method requires the conditional distribution functions of load...... process by a Markov process. Two different spectra from two tubular joints in an offshore structure (one narrow banded and one wide banded) are considered in an example. The results show that the simple direct method is quite efficient and results in a simulation speed of about 3000 load cycles per second...... ranges given the last peak values. Analytical estimates of these distribution functions are presented in the paper and compared with estimates based on a more accurate simulation method. In the more accurate simulation method samples at equidistant times are generated by approximating the stochastic load...

  16. Improved Load Shedding Scheme considering Distributed Generation

    DEFF Research Database (Denmark)

    Das, Kaushik; Nitsas, Antonios; Altin, Müfit

    2017-01-01

    With high penetration of distributed generation (DG), the conventional under-frequency load shedding (UFLS) face many challenges and may not perform as expected. This article proposes new UFLS schemes, which are designed to overcome the shortcomings of traditional load shedding scheme. These sche......With high penetration of distributed generation (DG), the conventional under-frequency load shedding (UFLS) face many challenges and may not perform as expected. This article proposes new UFLS schemes, which are designed to overcome the shortcomings of traditional load shedding scheme....... These schemes utilize directional relays, power flow through feeders, wind and PV measurements to optimally select the feeders to be disconnected during load shedding such that DG disconnection is minimized while disconnecting required amount of consumption. These different UFLS schemes are compared in terms...

  17. High power s-band vacuum load

    Energy Technology Data Exchange (ETDEWEB)

    Neubauer, Michael [Muons, Inc., Batavia, IL (United States); Dudas, Alan [Muons, Inc., Batavia, IL (United States); Krasnykh, Anatoly [SLAC National Accelerator Lab., Menlo Park, CA (United States)

    2016-12-29

    Through a combination of experimentation and calculation the components of a novel room temperature dry load were successfully fabricated. These components included lossy ceramic cylinders of various lengths, thicknesses, and percent of silicon carbide (SiC). The cylinders were then assembled into stainless steel compression rings by differential heating of the parts and a special fixture. Post machining of this assembly provided a means for a final weld. The ring assemblies were then measured for S-parameters, individually and in pairs using a low-cost TE10 rectangular to TE01 circular waveguide adapter specially designed to be part of the final load assembly. Matched pairs of rings were measured for assembly into the final load, and a sliding short designed and fabricated to assist in determining the desired short location in the final assembly. The plan for the project was for Muons, Inc. to produce prototype loads for long-term testing at SLAC. The STTR funds for SLAC were to upgrade and operate their test station to ensure that the loads would satisfy their requirements. Phase III was to be the sale to SLAC of loads that Muons, Inc. would manufacture. However, an alternate solution that involved a rebuild of the old loads, reduced SLAC budget projections, and a relaxed time for the replacement of all loads meant that in-house labor will be used to do the upgrade without the need for the loads developed in this project. Consequently, the project was terminated before the long term testing was initiated. However, SLAC can use the upgraded test stand to compare the long-term performance of the ones produced in this project with their rebuilt loads when they are available.

  18. Quantifying Training Loads in Contemporary Dance.

    Science.gov (United States)

    Jeffries, Annie C; Wallace, Lee; Coutts, Aaron J

    2017-07-01

    To describe the training demands of contemporary dance and determine the validity of using the session rating of perceived exertion (sRPE) to monitor exercise intensity and training load in this activity. In addition, the authors examined the contribution of training (ie, accelerometry and heart rate) and non-training-related factors (ie, sleep and wellness) to perceived exertion during dance training. Training load and ActiGraphy for 16 elite amateur contemporary dancers were collected during a 49-d period, using heart-rate monitors, accelerometry, and sRPE. Within-individual correlation analysis was used to determine relationships between sRPE and several other measures of training intensity and load. Stepwise multiple regressions were used to determine a predictive equation to estimate sRPE during dance training. Average weekly training load was 4283 ± 2442 arbitrary units (AU), monotony 2.13 ± 0.92 AU, strain 10677 ± 9438 AU, and average weekly vector magnitude load 1809,707 ± 1015,402 AU. There were large to very large within-individual correlations between training-load sRPE and various other internal and external measures of intensity and load. The stepwise multiple-regression analysis also revealed that 49.7% of the adjusted variance in training-load sRPE was explained by peak heart rate, metabolic equivalents, soreness, motivation, and sleep quality (y = -4.637 + 13.817%HR peak + 0.316 METS + 0.100 soreness + 0.116 motivation - 0.204 sleep quality). The current findings demonstrate the validity of the sRPE method for quantifying training load in dance, that dancers undertake very high training loads, and a combination of training and nontraining factors contribute to perceived exertion in dance training.

  19. USING BENCH PRESS LOAD TO PREDICT UPPER BODY EXERCISE LOADS IN PHYSICALLY ACTIVE INDIVIDUALS

    Directory of Open Access Journals (Sweden)

    Del P. Wong

    2013-03-01

    Full Text Available This study investigated whether loads for assistance exercises of the upper body can be predicted from the loads of the bench press exercise. Twenty-nine physically active collegiate students (age: 22.6 ± 2.5; weight training experience: 2.9 ± 2.1 years; estimated 1RM bench press: 54.31 ± 14.60 kg; 1RM: body weight ratio: 0.80 ± 0.22; BMI: 22.7 ± 2.1 kg·m-2 were recruited. The 6RM loads for bench press, barbell bicep curl, overhead dumbbell triceps extension, hammer curl and dumbbell shoulder press were measured. Test-retest reliability for the 5 exercises as determined by Pearson product moment correlation coefficient was very high to nearly perfect (0.82-0.98, p < 0.01. The bench press load was significantly correlated with the loads of the 4 assistance exercises (r ranged from 0.80 to 0.93, p < 0.01. Linear regression revealed that the bench press load was a significant (R2 range from 0.64 to 0.86, p < 0.01 predictor for the loads of the 4 assistance exercises. The following 6RM prediction equations were determined: (a Hammer curl = Bench press load (0.28 + 6.30 kg, (b Barbell biceps curl = Bench press load (0.33 + 6.20 kg, (c Overhead triceps extension = Bench press load (0.33 - 0.60 kg, and (d Dumbbell shoulder press = Bench press load (0.42 + 5.84 kg. The difference between the actual load and the predicted load using the four equations ranged between 6.52% and 8.54%, such difference was not significant. Fitness professionals can use the 6RM bench press load as a time effective and accurate method to predict training loads for upper body assistance exercises.

  20. Using bench press load to predict upper body exercise loads in physically active individuals.

    Science.gov (United States)

    Wong, Del P; Ngo, Kwan-Lung; Tse, Michael A; Smith, Andrew W

    2013-01-01

    This study investigated whether loads for assistance exercises of the upper body can be predicted from the loads of the bench press exercise. Twenty-nine physically active collegiate students (age: 22.6 ± 2.5; weight training experience: 2.9 ± 2.1 years; estimated 1RM bench press: 54.31 ± 14.60 kg; 1RM: body weight ratio: 0.80 ± 0.22; BMI: 22.7 ± 2.1 kg·m(-2)) were recruited. The 6RM loads for bench press, barbell bicep curl, overhead dumbbell triceps extension, hammer curl and dumbbell shoulder press were measured. Test-retest reliability for the 5 exercises as determined by Pearson product moment correlation coefficient was very high to nearly perfect (0.82-0.98, p press load was significantly correlated with the loads of the 4 assistance exercises (r ranged from 0.80 to 0.93, p press load was a significant (R(2) range from 0.64 to 0.86, p press load (0.28) + 6.30 kg, (b) Barbell biceps curl = Bench press load (0.33) + 6.20 kg, (c) Overhead triceps extension = Bench press load (0.33) - 0.60 kg, and (d) Dumbbell shoulder press = Bench press load (0.42) + 5.84 kg. The difference between the actual load and the predicted load using the four equations ranged between 6.52% and 8.54%, such difference was not significant. Fitness professionals can use the 6RM bench press load as a time effective and accurate method to predict training loads for upper body assistance exercises. Key pointsThe bench press load was significantly correlated with the loads of the 4 assistance exercises.No significant differences were found between the actual load and the predicted load in the four equations.6RM bench press load can be a time effective and accurate method to predict training loads for upper body assistance exercises.

  1. Heat Load Estimator for Smoothing Pulsed Heat Loads on Supercritical Helium Loops

    Science.gov (United States)

    Hoa, C.; Lagier, B.; Rousset, B.; Bonnay, P.; Michel, F.

    Superconducting magnets for fusion are subjected to large variations of heat loads due to cycling operation of tokamaks. The cryogenic system shall operate smoothly to extract the pulsed heat loads by circulating supercritical helium into the coils and structures. However the value of the total heat loads and its temporal variation are not known before the plasma scenario starts. A real-time heat load estimator is of interest for the process control of the cryogenic system in order to anticipate the arrival of pulsed heat loads to the refrigerator and finally to optimize the operation of the cryogenic system. The large variation of the thermal loads affects the physical parameters of the supercritical helium loop (pressure, temperature, mass flow) so those signals can be used for calculating instantaneously the loads deposited into the loop. The methodology and algorithm are addressed in the article for estimating the heat load deposition before it reaches the refrigerator. The CEA patented process control has been implemented in a Programmable Logic Controller (PLC) and has been successfully validated on the HELIOS test facility at CEA Grenoble. This heat load estimator is complementary to pulsed load smoothing strategies providing an estimation of the optimized refrigeration power. It can also effectively improve the process control during the transient between different operating modes by adjusting the refrigeration power to the need. This way, the heat load estimator participates to the safe operation of the cryogenic system.

  2. Effect of Internal Clearance on Load Distribution and Life of Radially Loaded Ball and Roller Bearings

    Science.gov (United States)

    Oswald, Fred B.; Zaretsky, Erwin V.; Poplawski, Joseph V.

    2012-01-01

    The effect of internal clearance on radially loaded deepgroove ball and cylindrical roller bearing load distribution and fatigue life was determined for four clearance groups defined in the bearing standards. The analysis was extended to negative clearance (interference) conditions to produce a curve of life factor versus internal clearance. Rolling-element loads can be optimized and bearing life maximized for a small negative operating clearance. Life declines gradually with positive clearance and rapidly with increasing negative clearance. Relationships were found between bearing life and internal clearance as a function of ball or roller diameter, adjusted for load. Results are presented as life factors for radially loaded bearings independent of bearing size or applied load. In addition, a modified Stribeck Equation is presented that relates the maximum rolling-element load to internal bearing clearance.

  3. Probabilistic model of bridge vehicle loads in port area based on in-situ load testing

    Science.gov (United States)

    Deng, Ming; Wang, Lei; Zhang, Jianren; Wang, Rei; Yan, Yanhong

    2017-11-01

    Vehicle load is an important factor affecting the safety and usability of bridges. An statistical analysis is carried out in this paper to investigate the vehicle load data of Tianjin Haibin highway in Tianjin port of China, which are collected by the Weigh-in- Motion (WIM) system. Following this, the effect of the vehicle load on test bridge is calculated, and then compared with the calculation result according to HL-93(AASHTO LRFD). Results show that the overall vehicle load follows a distribution with a weighted sum of four normal distributions. The maximum vehicle load during the design reference period follows a type I extremum distribution. The vehicle load effect also follows a weighted sum of four normal distributions, and the standard value of the vehicle load is recommended as 1.8 times that of the calculated value according to HL-93.

  4. The Statistical Properties of Host Load

    Directory of Open Access Journals (Sweden)

    Peter A. Dinda

    1999-01-01

    Full Text Available Understanding how host load changes over time is instrumental in predicting the execution time of tasks or jobs, such as in dynamic load balancing and distributed soft real‐time systems. To improve this understanding, we collected week‐long, 1 Hz resolution traces of the Digital Unix 5 second exponential load average on over 35 different machines including production and research cluster machines, compute servers, and desktop workstations. Separate sets of traces were collected at two different times of the year. The traces capture all of the dynamic load information available to user‐level programs on these machines. We present a detailed statistical analysis of these traces here, including summary statistics, distributions, and time series analysis results. Two significant new results are that load is self‐similar and that it displays epochal behavior. All of the traces exhibit a high degree of self‐similarity with Hurst parameters ranging from 0.73 to 0.99, strongly biased toward the top of that range. The traces also display epochal behavior in that the local frequency content of the load signal remains quite stable for long periods of time (150–450 s mean and changes abruptly at epoch boundaries. Despite these complex behaviors, we have found that relatively simple linear models are sufficient for short‐range host load prediction.

  5. Hood River Conservation Project load analysis

    Energy Technology Data Exchange (ETDEWEB)

    Stovall, T.K.

    1987-11-01

    As a part of the Hood River Conservation Project (HRCP), 314 homes were monitored to measure electrical energy use. The total electrical load, space heating load, water heating load (in about 200 homes), wood-stove heat output (in about 100 homes), and indoor temperature were monitored. Data were collected for one full year before and one full year after these homes were retrofit with conservation measures. Local weather information was also collected on a 15-min basis. This data base was used to evaluate the load savings attributable to HRCP. Two methods of weather normalization were used and showed close agreement. The weather-normalized diversified residential load savings on the Pacific Power and Light system and Hood River area peak days were >0.5 kW/household. The average spring, summer, and fall savings were much smaller, <0.1 kW/household. The load factor for the diversified residential load decreased following the conservation retrofit actions. 11 refs., 40 figs., 13 tabs.

  6. Electricity Crisis and Load Management in Bangladesh

    Directory of Open Access Journals (Sweden)

    Rajib Kanti Das

    2012-09-01

    Full Text Available Bangladesh is a densely populated country. Only a small part of her area is electrified which cover around 18% of total population. The people who are in the electrified area are suffering from severe load shedding. A systematic load management procedure related to demand side may improve the situation is the research problem. The major objectives serve by the research are to analyze contemporary electricity status with a view to drawing inference about demand supply gap and extracting benefits from load management. Data supplied by the Bangladesh Power Development Board, World Bank and outcome of survey are analyzed with some simple statistical tools to test the hypothesis. Analysis discloses that with properly managed uses of electricity with load switch and rotation week-end can improve the concurrent condition of electricity. Moreover, introducing smart distribution system, reducing system loss, shifting load to off-peak, large scale use of prepaid mete, observing energy week and using energy efficient home and office appliance are recommended to improve load through demand side management. Some other recommendations such as introducing alternative energy, public private partnership and using renewable energy development and producing energy locally are made for load management from the supply side.

  7. Factor structure underlying components of allostatic load.

    Directory of Open Access Journals (Sweden)

    Jeanne M McCaffery

    Full Text Available Allostatic load is a commonly used metric of health risk based on the hypothesis that recurrent exposure to environmental demands (e.g., stress engenders a progressive dysregulation of multiple physiological systems. Prominent indicators of response to environmental challenges, such as stress-related hormones, sympatho-vagal balance, or inflammatory cytokines, comprise primary allostatic mediators. Secondary mediators reflect ensuing biological alterations that accumulate over time and confer risk for clinical disease but overlap substantially with a second metric of health risk, the metabolic syndrome. Whether allostatic load mediators covary and thus warrant treatment as a unitary construct remains to be established and, in particular, the relation of allostatic load parameters to the metabolic syndrome requires elucidation. Here, we employ confirmatory factor analysis to test: 1 whether a single common factor underlies variation in physiological systems associated with allostatic load; and 2 whether allostatic load parameters continue to load on a single common factor if a second factor representing the metabolic syndrome is also modeled. Participants were 645 adults from Allegheny County, PA (30-54 years old, 82% non-Hispanic white, 52% female who were free of confounding medications. Model fitting supported a single, second-order factor underlying variance in the allostatic load components available in this study (metabolic, inflammatory and vagal measures. Further, this common factor reflecting covariation among allostatic load components persisted when a latent factor representing metabolic syndrome facets was conjointly modeled. Overall, this study provides novel evidence that the modeled allostatic load components do share common variance as hypothesized. Moreover, the common variance suggests the existence of statistical coherence above and beyond that attributable to the metabolic syndrome.

  8. Standardized Loads Acting in Knee Implants

    Science.gov (United States)

    Bergmann, Georg; Bender, Alwina; Graichen, Friedmar; Dymke, Jörn; Rohlmann, Antonius; Trepczynski, Adam; Heller, Markus O.; Kutzner, Ines

    2014-01-01

    The loads acting in knee joints must be known for improving joint replacement, surgical procedures, physiotherapy, biomechanical computer simulations, and to advise patients with osteoarthritis or fractures about what activities to avoid. Such data would also allow verification of test standards for knee implants. This work analyzes data from 8 subjects with instrumented knee implants, which allowed measuring the contact forces and moments acting in the joint. The implants were powered inductively and the loads transmitted at radio frequency. The time courses of forces and moments during walking, stair climbing, and 6 more activities were averaged for subjects with I) average body weight and average load levels and II) high body weight and high load levels. During all investigated activities except jogging, the high force levels reached 3,372–4,218N. During slow jogging, they were up to 5,165N. The peak torque around the implant stem during walking was 10.5 Nm, which was higher than during all other activities including jogging. The transverse forces and the moments varied greatly between the subjects, especially during non-cyclic activities. The high load levels measured were mostly above those defined in the wear test ISO 14243. The loads defined in the ISO test standard should be adapted to the levels reported here. The new data will allow realistic investigations and improvements of joint replacement, surgical procedures for tendon repair, treatment of fractures, and others. Computer models of the load conditions in the lower extremities will become more realistic if the new data is used as a gold standard. However, due to the extreme individual variations of some load components, even the reported average load profiles can most likely not explain every failure of an implant or a surgical procedure. PMID:24465856

  9. Standardized loads acting in knee implants.

    Directory of Open Access Journals (Sweden)

    Georg Bergmann

    Full Text Available The loads acting in knee joints must be known for improving joint replacement, surgical procedures, physiotherapy, biomechanical computer simulations, and to advise patients with osteoarthritis or fractures about what activities to avoid. Such data would also allow verification of test standards for knee implants. This work analyzes data from 8 subjects with instrumented knee implants, which allowed measuring the contact forces and moments acting in the joint. The implants were powered inductively and the loads transmitted at radio frequency. The time courses of forces and moments during walking, stair climbing, and 6 more activities were averaged for subjects with I average body weight and average load levels and II high body weight and high load levels. During all investigated activities except jogging, the high force levels reached 3,372-4,218N. During slow jogging, they were up to 5,165N. The peak torque around the implant stem during walking was 10.5 Nm, which was higher than during all other activities including jogging. The transverse forces and the moments varied greatly between the subjects, especially during non-cyclic activities. The high load levels measured were mostly above those defined in the wear test ISO 14243. The loads defined in the ISO test standard should be adapted to the levels reported here. The new data will allow realistic investigations and improvements of joint replacement, surgical procedures for tendon repair, treatment of fractures, and others. Computer models of the load conditions in the lower extremities will become more realistic if the new data is used as a gold standard. However, due to the extreme individual variations of some load components, even the reported average load profiles can most likely not explain every failure of an implant or a surgical procedure.

  10. A combined loading system integrated with portable winch and polyethylene chutes for loading of timber products

    Directory of Open Access Journals (Sweden)

    H. Hulusi Acar

    2016-01-01

    Full Text Available Truck loading operation is an important task during timber production operations in forestry. In Turkey, approximately 50 million timbers/logs are being produced per year, and then they are loaded into the logging trucks. The timber/logs are transported over the forest roads with an average of one million roundtrips. However, the traditional loading methods using manpower are mostly performed while some part is done by using loading machines which can be very costly and risky. This study aims developing a combined loading system in which heavy logs are loaded into logging trucks by pulling them by a log-line powered by a portable crane within the chute system. The slope of the log-line from ground to logging truck varied between 1% and 25%. Within the each work cycle of loading operation, only one log was loaded by pulling with portable crane. The average loading time was found as 161.8 seconds per cycle, in which 67% of the time was spent on pulling the log into the logging truck. The results indicated that the average pulling speed with crane power was 840.4 m/hr and productivity was calculated as 4.94 m3/hr. The result on system speed and productivity indicated close relations with results from previous studies. The hydraulic grapple loader or cranes are widely used and common loading machines, but they cannot be efficiently used in forestry operations, especially ones having a low timber productivity rate or having low economic value timber. In these conditions, loading methods that are cost efficient and do not require higher production rate should be employed. Therefore, a combined loading system introduced in this study can be a feasible solution for loading operations in those cases. Furthermore, it is believed that this loading system integrated with a portable crane can be cost efficient and time saving solution, as well as ergonomic and safe method in the field.

  11. Strength of concrete structures under dynamic loading

    Energy Technology Data Exchange (ETDEWEB)

    Kumpyak, O. G., E-mail: ogkumpyak@yandex.ru; Galyautdinov, Z. R., E-mail: gazr@yandex.ru; Kokorin, D. N., E-mail: kokorindenn@yandex.ru [Tomsk State University of Architecture and Building, 2, Solyanaya Sq., 634003, Tomsk (Russian Federation)

    2016-01-15

    The use of elastic supports is one the efficient methods of decreasing the dynamic loading. The paper describes the influence of elastic supports on the stress-strain state of steel concrete structures exposed to one-time dynamic loading resulting in failure. Oblique bending beams on elastic supports and their elastic, elastoplastic, and elastoplastic consolidation behavior are considered in this paper. For numerical calculations the developed computer program is used based on the finite element method. Research findings prove high efficiency of elastic supports under dynamic loading conditions. The most effective behavior of elastic supports is demonstrated at the elastoplastic stage. A good agreement is observed between the theoretical and experimental results.

  12. Feasability Study of Electronic Load Sensing Concept

    DEFF Research Database (Denmark)

    Hansen, Michael Rygaard; Andersen, Torben O.; Pedersen, Henrik C.

    2006-01-01

    circuit axial piston pump. Emphasis is on performance robustness with respect to both variations in internal physical parameters of the pump as well as the type of application dependant load that the pump is expected to drive.The research reflect mechatronics as an integrated design process, while......Electronic load sensing (ELS) systems have long been expected to start replacing traditional (hydro-mechanical) load sensing (LS) systems, which today are the standard on most medium and high-end mobile hydraulic applications. The reason for this being the potentials that ELS brings relative...

  13. A Server for ARINC 615A Loading

    OpenAIRE

    Gustafsson, Markus

    2013-01-01

    The development of the next generation of Saab's multirole combat aircraft the JAS 39 Gripen includes developing a lot of new software for the aircraft's on-board computers. The new software has to be loaded into these computers routinely, in order to carry out testing on it. This is currently a slow and tedious process. In order to load the computers a protocol defined in the ARINC 615A standard is used. Today Saab uses commercial software applications implementing this protocol for the load...

  14. Numerical Analyses of Plate Loading Test

    Directory of Open Access Journals (Sweden)

    Ionuţ-Ovidiu Toma

    2009-01-01

    Full Text Available A numerical simulation of plate loading test, in order to underlines the size effect on settlements and derived values of geotechnical parameters, is shown. The study is based on the comparison between the results obtained by Finite Element Method (FEM using the Mohr-Coulomb soil model and by some observations from literature. The obtained numerical results revealed that the subgrade reaction coefficient is strictly dependent on parameters like size of the loaded area and loading magnitude, and thus completely general and generic, and not a fundamental material property of soil that can somehow be determined rationally, as often one claims to be.

  15. Synthesis of polyoxometalate-loaded epoxy composites

    Science.gov (United States)

    Anderson, Benjamin J

    2014-10-07

    The synthesis of a polyoxometalate-loaded epoxy uses a one-step cure by applying an external stimulus to release the acid from the polyoxometalate and thereby catalyze the cure reaction of the epoxy resin. Such polyoxometalate-loaded epoxy composites afford the cured epoxy unique properties imparted by the intrinsic properties of the polyoxometalate. For example, polyoxometalate-loaded epoxy composites can be used as corrosion resistant epoxy coatings, for encapsulation of electronics with improved dielectric properties, and for structural applications with improved mechanical properties.

  16. Wind turbine blade testing under combined loading

    DEFF Research Database (Denmark)

    Roczek-Sieradzan, Agnieszka; Nielsen, Magda; Branner, Kim

    2011-01-01

    The paper presents full-scale blade tests under a combined flap- and edgewise loading. The main aim of this paper is to present the results from testing a wind turbine blade under such conditions and to study the structural behavior of the blade subjected to combined loading. A loading method using...... anchor plates was applied, allowing transverse shear distortion. The global and local deformation of the blade as well as the reproducibility of the test was studied and the results from the investigations are presented....

  17. Integrating Autonomous Load Controllers in Power Systems

    DEFF Research Database (Denmark)

    Douglass, Philip James

    and reliability constraints in power systems are motivating research into new control architectures suitable for such a large and complex system. The focus of this thesis is on an intermediate stage of evolution between today's largely passive loads and a future "Internet of Things". Specifically...... to the fluctuating production. The large number and geographic dispersion of loads make coordinating their behavior challenging. New telecommunication technology has reduced the cost of linking devices, promising a future "Internet of Things" where loads are fully networked. Strict real-time constraints...

  18. Modelling and Simulation of Wave Loads

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard; Thoft-Christensen, Palle

    A simple model of the wave load on slender members of offshore structures is described. The wave elevation of the sea state is modelled by a stationary Gaussian process. A new procedure to simulate realizations of the wave loads is developed. The simulation method assumes that the wave particle...... velocity can be approximated by a Gaussian Markov process. Known approximate results for the first-passage density or equivalently, the distribution of the extremes of wave loads are presented and compared with rather precise simulation results. It is demonstrated that the approximate results...

  19. Load control system. [for space shuttle external tank ground tests

    Science.gov (United States)

    Grosse, J. C.

    1977-01-01

    The load control system developed for the shuttle external structural tests is described. The system consists of a load programming/display module, and a load control module along with the following hydraulic system components: servo valves, dump valves, hydraulic system components, and servo valve manifold blocks. One load programming/display subsystem can support multiple load control subsystem modules.

  20. 46 CFR 196.40-15 - Load line marks.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Load line marks. 196.40-15 Section 196.40-15 Shipping... Markings on Vessels § 196.40-15 Load line marks. (a) Vessels assigned a load line shall have the deck line and the load line marks permanently marked or embossed as required by Subchapter E (Load Lines) of...

  1. Identification of Interleukin-27 (IL-27)/IL-27 Receptor Subunit Alpha as a Critical Immune Axis for In Vivo HIV Control.

    Science.gov (United States)

    Ruiz-Riol, M; Berdnik, D; Llano, A; Mothe, B; Gálvez, C; Pérez-Álvarez, S; Oriol-Tordera, B; Olvera, A; Silva-Arrieta, S; Meulbroek, M; Pujol, F; Coll, J; Martinez-Picado, J; Ganoza, C; Sanchez, J; Gómez, G; Wyss-Coray, T; Brander, C

    2017-08-15

    Intact and broad immune cell effector functions and specific individual cytokines have been linked to HIV disease outcome, but their relative contribution to HIV control remains unclear. We asked whether the proteome of secreted cytokines and signaling factors in peripheral blood can be used to discover specific pathways critical for host viral control. A custom glass-based microarray, able to measure >600 plasma proteins involved in cell-to-cell communication, was used to measure plasma protein profiles in 96 HIV-infected, treatment-naive individuals with high (>50,000) or low (HIV RNA copies/ml) viral loads. Univariate and regression model analysis demonstrate that plasma levels of soluble interleukin-27 (IL-27) are significantly elevated in individuals with high plasma viremia (P HIV-DNA copy numbers in peripheral blood mononuclear cells (PBMC) (Rho = 0.4011; P = 0.0027). Moreover, soluble IL-27 plasma levels are negatively associated with the breadth and magnitude of the total virus-specific T-cell responses and directly with plasma levels of molecules involved in Wnt/β-catenin signaling. In addition to IL-27, gene expression levels of the specific IL-27 receptor (IL27RA) in PBMC correlated directly with both plasma viral load (Rho = 0.3531; P = 0.0218) and the proviral copy number in the peripheral blood as an indirect measure of partial viral reservoir (Rho = 0.4580; P = 0.0030). These results were validated in unrelated cohorts of early infected subjects as well as subjects before and after initiation of antiretroviral treatment, and they identify IL-27 and its specific receptor as a critical immune axis for the antiviral immune response and as robust correlates of viral load and proviral reservoir size in PBMC.IMPORTANCE The detailed knowledge of immune mechanisms that contribute to HIV control is a prerequisite for the design of effective treatment strategies to achieve HIV cure. Cells communicate with each other by secreting signaling proteins, and the

  2. Success of immediate loading implants compared to conventionally-loaded implants: a literature review.

    Science.gov (United States)

    Al-Sawai, Abdul-Aziz; Labib, Hussein

    2016-08-01

    The purpose of this systematic literature review was to compare the clinical performance between conventionally- (delayed) and immediately-loaded implants. A literature search of studies published between 1995 and 2012 was performed using several electronic databases and the following key words: "immediate loading", "dental implants", "immediate function", "early loading", "oral implants", "immediate restoration", and "systematic review" was performed. The electronic search was supplemented with hand-searching in dental journals and cross-referencing within the selected articles. Studies were considered for inclusion if they analyzed the success of the immediate loading protocol for implants, with emphasis given to randomized, controlled clinical trials. Among the clinical studies extracted from the literature, 120 studies met the inclusion criteria and were included in this systematic review. These studies included trials that involved yielded consistent results of success rates of immediately-loaded implants comparable to those known from conventionally-loaded implants, which were subjected to the immediate loading protocol or other loading protocols. According to the findings, there is evidence to suggest that immediate loading protocols demonstrate high implant survival rates and could be cautiously recommended for certain clinical situations. However, studies with a high level of evidence, especially randomized, controlled trials, performed over a longer timeframe are required to show a clear benefit over conventional and other loading types. © 2015 Wiley Publishing Asia Pty Ltd.

  3. Evaluation of Muscle Mechanical Capacities through the Two-load Method: Optimization of the Load Selection.

    Science.gov (United States)

    Pérez-Castilla, Alejandro; Jaric, Slobodan; Feriche, Belén; Padial, Paulino; García-Ramos, Amador

    2017-04-25

    Recent research has revealed that the force-velocity relationship obtained from the 'two-load method' (i.e., functional movements tested against just 2 external loads) could be a feasible method for the selective assessment of muscle force, velocity, and power-producing capacities. The study investigated the reliability and concurrent validity of the outcomes of the two-load method observed from (1) farther vs. closer data points (20-70%1RM, 30-60%1RM, and 40-50%1RM), and (2) force-biased (50-70%1RM) vs. velocity-biased (20-40%1RM) data points. Twenty-two men were tested on a ballistic bench press throw performed against 6 incremental loads ranging from 20% to 70% of the bench press one-repetition maximum (1RM). The two-load methods were constructed based on pairs of individually selected external loads and compared with the outcome of the force-velocity regression method applied to all 6 loads. The reliability and validity of the force-velocity relationship parameters decreased with the proximity of the data points (40-50%1RM loads (i.e., lighter and heavier loads, respectively) revealed a similar, but relatively moderate reliability and validity. Overall, the farthest pair of loads (i.e., 20%1RM and 70%1RM) revealed the highest reliability (CV = 5.5%, ICC = 0.89) and validity (r = 0.98) among all the two-load methods evaluated. These results demonstrate that the 20-70%1RM two-load method could be a feasible approach for testing individual muscle mechanical capacities, while the observed outcomes could be the most reliable and valid when obtained from the farthest pairs of applied loads.

  4. multilevel buck converter for automotive electrical load

    African Journals Online (AJOL)

    user

    MULTILEVEL BUCK CONVERTER FOR AUTOMOTIVE ELECTRICAL LOAD. E. T. Yabefa1,* and D. Ebregbe2. 1ELECTRICAL DEPARTMENT, BAYELSA STATE COLLEGE OF ARTS & SCIENCE (BYCAS) YENAGOA, BAYELSA STATE NIGERIA. 2ELECTRICAL ENGINEERING DEPARTMENT, NIGER DELTA UNIVERSITY, ...

  5. Handball load and shoulder injury rate

    DEFF Research Database (Denmark)

    Møller, M; Nielsen, R O; Attermann, J

    2017-01-01

    by scapular control, isometric shoulder strength or glenohumeral range of motion (ROM). Methods 679 players (14-18 years) provided weekly reports on shoulder injury and handball load (training and competition hours) over 31 weeks using the SMS, phone and medical examination system. Handball load in a given......Background Knowledge of injury patterns, an essential step towards injury prevention, is lacking in youth handball. Aim To investigate if an increase in handball load is associated with increased shoulder injury rates compared with a minor increase or decrease, and if an association is influenced...... week was categorised into (1) 60% relative to the weekly average amount of handball load the preceding 4 weeks. Assessment of shoulder isometric rotational and abduction strength, ROM and scapular control...

  6. Weapons Load Crew Management Program Update

    National Research Council Canada - National Science Library

    Richardson, Allan

    1997-01-01

    .... Widely used throughout the Air Force (including Air National Guard and Reserve units), WLCMP is a efficient way of managing load crew training, eliminating much of the time and manpower that is required by manual tracking procedures...

  7. Development of Engine Loads Methodology Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This SBIR seeks to improve the definition of design loads for rocket engine components such that higher performing, lighter weight engines can be developed more...

  8. Introduction to Single Piles under Lateral Loading

    DEFF Research Database (Denmark)

    Augustesen, Anders; Ibsen, Lars Bo

    The purpose of this chapter is to give a short introduction to single piles subjected to lateral loading. First, the observed behaviour of laterally loaded piles is described, i.e. the effects of loading conditions, installation procedure, pile type etc. on pile behaviour are presented (section 1.......2). The description is based on results of laboratory tests, full-scale field tests as well as numerical investigations presented in literature. Second, general methods that attempt to model lateral pile response are discussed in section 1.4. Third, focus is paid to a widely used method for prediction of the response...... of a lateral loaded pile, namely the Winkler approach in which the pile is modelled as an elastic beam on an elastic foundation (section 1.5). The soil response and thereby the elastic foundation is represented by springs with nonlinear behaviour (p-y curves). In section 1.6 different types and formulations...

  9. Exercise Load Measurement Insole (ELMI) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The Exercise Load Measurement Insole (ELMI) is a system that is designed to measure normal and shear foot forces during exercise. The ELMI system is lightweight,...

  10. Load balancing multimodule switching power converters

    Science.gov (United States)

    Mclyman, W. T.; Wester, G. W.

    1979-01-01

    Regulating system individually adjusts duty cycles of modules so that all share load equally, thus, protects individual modules and their components from overload and increases reliability and life expectancy. Converters are alternative to high-power, single unit systems.

  11. Final Project Report Load Modeling Transmission Research

    Energy Technology Data Exchange (ETDEWEB)

    Lesieutre, Bernard [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Bravo, Richard [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Yinger, Robert [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Chassin, Dave [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Huang, Henry [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Lu, Ning [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Hiskens, Ian [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Venkataramanan, Giri [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2012-03-31

    The research presented in this report primarily focuses on improving power system load models to better represent their impact on system behavior. The previous standard load model fails to capture the delayed voltage recovery events that are observed in the Southwest and elsewhere. These events are attributed to stalled air conditioner units after a fault. To gain a better understanding of their role in these events and to guide modeling efforts, typical air conditioner units were testing in laboratories. Using data obtained from these extensive tests, new load models were developed to match air conditioner behavior. An air conditioner model is incorporated in the new WECC composite load model. These models are used in dynamic studies of the West and can impact power transfer limits for California. Unit-level and systemlevel solutions are proposed as potential solutions to the delayed voltage recovery problem.

  12. Quantum load balancing in ad hoc networks

    Science.gov (United States)

    Hasanpour, M.; Shariat, S.; Barnaghi, P.; Hoseinitabatabaei, S. A.; Vahid, S.; Tafazolli, R.

    2017-06-01

    This paper presents a novel approach in targeting load balancing in ad hoc networks utilizing the properties of quantum game theory. This approach benefits from the instantaneous and information-less capability of entangled particles to synchronize the load balancing strategies in ad hoc networks. The quantum load balancing (QLB) algorithm proposed by this work is implemented on top of OLSR as the baseline routing protocol; its performance is analyzed against the baseline OLSR, and considerable gain is reported regarding some of the main QoS metrics such as delay and jitter. Furthermore, it is shown that QLB algorithm supports a solid stability gain in terms of throughput which stands a proof of concept for the load balancing properties of the proposed theory.

  13. Predicting reinforced concrete response to blast loads

    National Research Council Canada - National Science Library

    Jacques, Eric; Lloyd, Alan; Saatcioglu, Murat

    2013-01-01

    .... The results are presented in graphical format in terms of structural load-deformation characteristics, single degree of freedom displacement--time histories and iso-displacement pressure-impulse diagrams...

  14. Multifrequency Printed Antennas Loaded with Metamaterial Particles

    Directory of Open Access Journals (Sweden)

    D. Segovia-Vargas

    2009-06-01

    Full Text Available This paper provides a review of printed antennas loaded with metamaterial particles. This novel technique allows developing printed antennas with interesting features such as multifrequency (simultaneous operation over two or more frequency bands and multifunctionality (e. g. radiation pattern diversity. Moreover, compactness is also achieved and the main advantages of conventional printed antennas (light weight, low profile, low cost ... are maintained. Different types of metamaterial-loaded printed antennas are reviewed: printed dipoles and patch antennas. Several prototypes are designed, manufactured and measured showing good results. Furthermore, simple but accurate equivalent models are proposed. These models allow an easy and quick design of metamaterial-loaded printed antennas. Finally, two interesting applications based on the proposed antennas are reviewed: the patch antennas are used as radiating elements of emerging active RFID systems in the microwave band and the metamaterial-loaded printed dipoles are employed to increase the performance of log-periodic arrays.

  15. Home Appliance Load Scheduling with SEMIAH

    DEFF Research Database (Denmark)

    Jacobsen, Rune Hylsberg; Ghasem Azar, Armin; Zhang, Qi

    2015-01-01

    The European research project SEMIAH aims at designing a scalable infrastructure for residential demand response. This paper presents the progress towards a centralized load scheduling algorithm for controlling home appliances taking power grid constraints and satisfaction of consumers into account....

  16. LIGHT-WEIGHT LOAD-BEARING STRUCTURE

    DEFF Research Database (Denmark)

    2009-01-01

    The invention relates to a light-weight load-bearing structure (1) with optimized compression zone (2), where along one or more compression zones (2) in the structure (1) to be cast a core (3) of strong concrete is provided, which core (3) is surrounded by concrete of less strength (4) compared...... to the core (3) of strong concrete. The invention also relates to a method of casting of light-weight load-bearing structures (1) with optimized compression zone (2) where one or more channels, grooves, ducts, pipes and/or hoses (5) formed in the load-bearing structure (1) serves as moulds for moulding one...... or more cores (3) of strong concrete in the light-weight load-bearing structure (1)....

  17. Radiopure Metal-Loaded Liquid Scintillator

    Energy Technology Data Exchange (ETDEWEB)

    Rosero, Richard [Brookhaven National Lab. (BNL), Upton, NY (United States). Chemistry Dept.; Yeh, Minfang [Brookhaven National Lab. (BNL), Upton, NY (United States). Chemistry Dept.

    2015-03-18

    Metal-loaded liquid scintillator plays a key role in particle and nuclear physics experiments. The applications of metal ions in various neutrino experiments and the purification methods for different scintillator components are discussed in this paper.

  18. Loaded Gelled Bipropellants for Optimized Performance Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The focus of this program is the development and validation of formulations, and development methodologies, for optimizing high-performance particulate-loaded...

  19. Heat loads in hypersonic vehicle design

    Energy Technology Data Exchange (ETDEWEB)

    Hirschel, E.H. [Daimler-Benz Aerospace AG, Muenchen (Germany)

    1999-12-01

    Heat loads are the major issue in high-speed vehicle design. Heat loads prediction capabilities need to be improved with regard to the materials and structure concept, and the aerodynamic and propulsion performance. Surface radiation cooling is the basic means to reduce heat loads on high-speed vehicles. Strong couplings can exist with the aerodynamic performance of vehicles, the structure and materials design, and flow-physics and thermochemical phenomena. Qualitative knowledge is available to interpret (computation) results and flight data, and to give the designer insight into related disciplinary and interdisciplinary vehicle design problems. Flow-physics and thermo-chemical models in prediction tools are inadequate. Heat loads and the related surface-temperature effects pose very important and challenging research and development problems. (orig.)

  20. Assessment of mother-to-child HIV-1 and HIV-2 transmission: an AIDS reference laboratory collaborative study.

    Science.gov (United States)

    Pádua, E; Almeida, C; Nunes, B; Cortes Martins, H; Castela, J; Neves, C; Paixão, M T

    2009-03-01

    led to false-negative maternal results in a significant proportion of cases. In part this may have been attributable to very low HIV DNA loads as well as primer template mismatches. HIV infection was not documented in children born to mothers with negative HIV DNA PCR results.

  1. Design of sandwich beams for concentrated loading

    Science.gov (United States)

    Kim, Jongman

    Although sandwich construction offers well-known advantages for high stiffness with light-weight, the problem of designing a sandwich structure to withstand localized loading such as might result from accidental impact, for example, is important. The review of the literature and experimental results performed by the author has shown that current design and analysis procedures are not suitable for predictions of the response of sandwich structures for concentrated loading. To investigate the response of sandwich structures to concentrated loading, experiments were carried out on beam specimens with polyurethane foam core with various densities and thickness, and faces made of AS4/3501-6 carbon/epoxy fiber composite of various thickness under three point loading, which gives a concentrated loading. Overall deformation was measured, along with strains from both surface and embedded gages. Additionally, compression tests and torsion tests have been done for the polyurethane foam used as core in the sandwich beam to characterize its yield properties. Many theories, including classical theory, first order shear deformation theory, higher order theory, elasticity and FE analysis, were compared with the three-point bending experiments. A two-dimensional elasticity solution, which is suitable for sandwich beams under simply support boundary conditions, was used to obtain the strain/stress distribution, failure prediction and optimization work. The common failure modes of sandwich beams have been observed, including core failure in compression and shear failure in core, delamination, and fiber failure in the face. The failure modes can be predicted for sandwich beams under localized loading using elasticity theory and the failure is controlled by a failure mode with the lowest load. An algorithm developed by Swanson and Kim was used to predict the optimum design of sandwich structures for strength to weight under concentrated loading and compared with experimental yield or

  2. LTE Load Balancing dengan Skenario Game Theory

    Directory of Open Access Journals (Sweden)

    Nila Putri Mardela

    2013-09-01

    Full Text Available Adanya multi user yang meminta untuk dilayani dengan baik dalam kondisi apapun terutama dalam kondisi cell yang congested tentunya menjadi hal yang sangat penting untuk diperhatikan dalam sistem komunikasi wireless termasuk dalam hal ini untuk teknologi Long Term Evolution (LTE sehingga diperlukan suatu proses dalam jaringan yang dapat menanggulangi permintaan user ini. Proses yang dapat dilakukan adalah dengan load balancing. Untuk memodelkan interaksi dari elemen jaringan yang melakukan load balancing , maka dibutuhkan suatu teknik atau skenario sehingga dicapai suatu keputusan yang rasional untuk dilakukannya load balancing. Teknik yang dapat digunakan adalah skenario game theory. Dalam tugas akhir yang berjudul LTE Load Balancing dengan Skenario Game Theory ini diusulkan metode Load Balancing Cooperative Game pada LTE dimana setiap tindakan yang dilakukan dalam rangka load balancing didasarkan terhadap nilai utilitas yang akan didapatkan, dan setiap eNB berhak memilih tindakan yang memiliki nilai utilitas maksimum. Efek dari load balancing yang diinginkan adalah penurunan jumlah drop call sebagai indikasi peningkatan layanan dan peningkatan utilitas eNB sebagai indikasi pengoptimalan utilitas bandwidth yang tidak terpakai. Dengan menerapkan LTE Load Balancing dengan Skenario Game Theory ini maka dapat dicapai penurunan jumlah drop call sebesar 92,33%, peningkatan utilitas eNB penolong sebesar 41,24%, dan 0,249% untuk peningkatan utilitas eNB congested yang meminta bantuan. Apabila dalam skema handover user dari eNB cell sumber yang congested ke eNB cell tetangga yang tidak congested ditambahkan syarat bahwa RSRP user dari eNB cell tetangga lebih besar dari pada eNB cell sumber maka penurunan drop call yang dicapai adalah sebesar 37,12%, peningkatan utilitas eNB penolong adalah sebesar 9,375%, dan peningkatan utilitas eNB congested yang meminta bantuan adalah sebesar 0,249%.

  3. Gearbox Reliability Collaborative (GRC) Description and Loading

    Energy Technology Data Exchange (ETDEWEB)

    Oyague, F.

    2011-11-01

    This document describes simulated turbine load cases in accordance to the IEC 61400-1 Ed.3 standard, which is representative of the typical wind turbine design process. The information presented herein is intended to provide a broad understanding of the gearbox reliability collaborative 750kW drivetrain and turbine configuration. In addition, fatigue and ultimate strength drivetrain loads resulting from simulations are presented. This information provides the bases for the analytical work of the gearbox reliability collaborative effort.

  4. Foot Marching, Load Carriage, and Injury Risk

    Science.gov (United States)

    2016-05-01

    Knapik, and J.J. 1994. Exercise, training and injuries. Sports Med 18(3): 202-1. 35. APHC (Prov) Blister Prevention Factsheet. 2015. Available at...1.5 Flashlight, other equipment 2 Approach Load Fighting Load + 32*pounds = 102* pounds Assault rucksack with attachments 9 Hydration bladder...Men 475,745) Source: Knapik J et al. Stress Fracture Risk Factors in Basic Combat Training, 2012. Int J Sports Med, 33: 940–946. Men n

  5. MCO loading and cask loadout technical manual

    Energy Technology Data Exchange (ETDEWEB)

    PRAGA, A.N.

    1998-10-01

    A compilation of the technical basis for loading a multi-canister overpack (MCO) with spent nuclear fuel and then placing the MCO into a cask for shipment to the Cold Vacuum Drying Facility. The technical basis includes a description of the process, process technology that forms the basis for loading alternatives, process control considerations, safety considerations, equipment description, and a brief facility structure description.

  6. ANTHROPOGENIC LOAD ON RIVERS OF URBAN AREAS

    OpenAIRE

    Kurochkina Valentina Aleksandrovna; Bogomolova Tat’yana Gennad’evna; Kirov Borislav Lyubomirov

    2016-01-01

    The increasing speed of urbanization and population growth lead to the increasing anthropogenic load on water bodies. The urbanization processes in Russia are more intensive than in other countries. The dense population and great industrial potential lead to the fact that the urbanized territories become the main sources of water pollution. That’s why the environmental control of the state of water objects is needed. In the article the authors study the problem of anthropogenic load impact on...

  7. Economic Load Dispatch Using Grey Wolf Optimization

    OpenAIRE

    Dr.Sudhir Sharma; Shivani Mehta

    2015-01-01

    This paper presents grey wolf optimization (GWO) to solve convex economic load dispatch (ELD) problem. Grey Wolf Optimization (GWO) is a new meta-heuristic inspired by grey wolves. The leadership hierarchy and hunting mechanism of the grey wolves is mimicked in GWO. The objective of ELD problem is to minimize the total generation cost while fulfilling the different constraints, when the required load of power system is being supplied. The proposed technique is implemented on two d...

  8. Mechanical Predictors of Discomfort during Load Carriage.

    Directory of Open Access Journals (Sweden)

    Patrick D Wettenschwiler

    Full Text Available Discomfort during load carriage is a major issue for activities using backpacks (e.g. infantry maneuvers, children carrying school supplies, or outdoor sports. It is currently unclear which mechanical parameters are responsible for subjectively perceived discomfort. The aim of this study was to identify objectively measured mechanical predictors of discomfort during load carriage. We compared twelve different configurations of a typical load carriage system, a commercially available backpack with a hip belt. The pressure distribution under the hip belt and the shoulder strap, as well as the tensile force in the strap and the relative motion of the backpack were measured. Multiple linear regression analyses were conducted to investigate possible predictors of discomfort. The results demonstrate that static peak pressure, or alternatively, static strap force is a significant (p<0.001 predictor of discomfort during load carriage in the shoulder and hip region, accounting for 85% or more of the variation in discomfort. As an additional finding, we discovered that the regression coefficients of these predictors are significantly smaller for the hip than for the shoulder region. As static peak pressure is measured directly on the body, it is less dependent on the type of load carriage system than static strap force. Therefore, static peak pressure is well suited as a generally applicable, objective mechanical parameter for the optimization of load carriage system design. Alternatively, when limited to load carriage systems of the type backpack with hip belt, static strap force is the most valuable predictor of discomfort. The regionally differing regression coefficients of both predictors imply that the hip region is significantly more tolerant than the shoulder region. In order to minimize discomfort, users should be encouraged to shift load from the shoulders to the hip region wherever possible, at the same time likely decreasing the risk of low

  9. Optimizing Preseason Training Loads in Australian Football.

    Science.gov (United States)

    Carey, David L; Crow, Justin; Ong, Kok-Leong; Blanch, Peter; Morris, Meg E; Dascombe, Ben J; Crossley, Kay M

    2018-02-14

    To investigate whether preseason training plans for Australian football can be computer generated using current training-load guidelines to optimize injury-risk reduction and performance improvement. A constrained optimization problem was defined for daily total and sprint distance, using the preseason schedule of an elite Australian football team as a template. Maximizing total training volume and maximizing Banister-model-projected performance were both considered optimization objectives. Cumulative workload and acute:chronic workload-ratio constraints were placed on training programs to reflect current guidelines on relative and absolute training loads for injury-risk reduction. Optimization software was then used to generate preseason training plans. The optimization framework was able to generate training plans that satisfied relative and absolute workload constraints. Increasing the off-season chronic training loads enabled the optimization algorithm to prescribe higher amounts of "safe" training and attain higher projected performance levels. Simulations showed that using a Banister-model objective led to plans that included a taper in training load prior to competition to minimize fatigue and maximize projected performance. In contrast, when the objective was to maximize total training volume, more frequent training was prescribed to accumulate as much load as possible. Feasible training plans that maximize projected performance and satisfy injury-risk constraints can be automatically generated by an optimization problem for Australian football. The optimization methods allow for individualized training-plan design and the ability to adapt to changing training objectives and different training-load metrics.

  10. Environmental stress, psychological stress and allostatic load.

    Science.gov (United States)

    Clark, Michael S; Bond, Malcolm J; Hecker, Jane R

    2007-01-01

    The mechanism by which chronic caregiving stress results in poor health is not well understood. The objective was to determine whether such a mechanism may be allostatic load, a novel concept specifying physiological systems that may suffer cumulative wear and tear following chronic stress, leading collectively to poor health. The study examines the association of allostatic load with environmental and psychological stress in the contexts of dementia caregiving and relinquishment of care, and is a 2-year longitudinal comparison of three groups: 80 new dementia spouse caregivers, 120 veteran caregivers, and 60 non-caregivers. Data comprised allostatic load markers and environmental and psychological stress measures. Cross-lagged analyses produced a statistically significant association between psychological stress and one allostatic load component (primary mediators). Psychological stress was a better predictor of primary mediators than environmental stress. Primary mediators rose with time for caregivers, but not for non-caregivers. A greater rise was evident for caregivers who had relinquished their role by the second year, although the level of psychological stress actually declined. Primary mediators are a key component of the relationship between allostatic load and prior stress. When allostatic load is treated as an outcome of stress, it is important to distinguish environmental and psychological stress.

  11. Characteristics of Braced Excavation under Asymmetrical Loads

    Directory of Open Access Journals (Sweden)

    Changjie Xu

    2013-01-01

    Full Text Available Numerous excavation practices have shown that large discrepancies exist between field monitoring data and calculated results when the conventional symmetry-plane method (with half-width is used to design the retaining structure under asymmetrical loads. To examine the characteristics of a retaining structure under asymmetrical loads, we use the finite element method (FEM to simulate the excavation process under four different groups of asymmetrical loads and create an integrated model to tackle this problem. The effects of strut stiffness and wall length are also investigated. The results of numerical analysis clearly imply that the deformation and bending moment of diaphragm walls are distinct on different sides, indicating the need for different rebar arrangements when the excavation is subjected to asymmetrical loads. This study provides a practical approach to designing excavations under asymmetrical loads. We analyze and compare the monitoring and calculation data at different excavation stages and find some general trends. Several guidelines on excavation design under asymmetrical loads are drawn.

  12. DNS load balancing in the CERN cloud

    Science.gov (United States)

    Reguero Naredo, Ignacio; Lobato Pardavila, Lorena

    2017-10-01

    Load Balancing is one of the technologies enabling deployment of large-scale applications on cloud resources. A DNS Load Balancer Daemon (LBD) has been developed at CERN as a cost-effective way to balance applications accepting DNS timing dynamics and not requiring persistence. It currently serves over 450 load-balanced aliases with two small VMs acting as master and slave. The aliases are mapped to DNS subdomains. These subdomains are managed with DDNS according to a load metric, which is collected from the alias member nodes with SNMP. During the last years, several improvements were brought to the software, for instance: support for IPv6, parallelization of the status requests, implementing the client in Python to allow for multiple aliases with differentiated states on the same machine or support for application state. The configuration of the Load Balancer is currently managed by a Puppet type. It discovers the alias member nodes and gets the alias definitions from the Ermis REST service. The Aiermis self-service GUI for the management of the LB aliases has been produced and is based on the Ermis service above that implements a form of Load Balancing as a Service (LBaaS). The Ermis REST API has authorisation based in Foreman hostgroups. The CERN DNS LBD is Open Software with Apache 2 license.

  13. Predicting Lifetime of a Thermomechanically Loaded Component

    Science.gov (United States)

    Murthy, Pappu L. N.; Gyekenyesi, John Z.; Mital, Subodh; Brewer, David N.

    2006-01-01

    NASALIFE is a computer program for predicting the lifetime, as affected by low cycle fatigue (LCF) and creep rupture, of a structural component subject to temporally varying, multiaxial thermomechanical loads. The component could be, for example, part of an aircraft turbine engine. Empirical data from LCF tests, creep rupture tests, and static tensile tests are used as references for predicting the number of missions the component can withstand under a given thermomechanical loading condition. The user prepares an input file containing the creep-rupture and cyclic-fatigue information, temperature-dependent material properties, and mission loading and control flags. The creep rupture information can be entered in tabular form as stress versus life or by means of parameters of the Larson-Miller equation. The program uses the Walker mean-stress model to adjust predicted life for ranges of the ratio between the maximum and minimum stresses. Data representing complex load cycles are reduced by the rainflow counting method. Miner's rule is utilized to combine the damage at different load levels. Finally, the program determines the total damage due to creep and combines it with the fatigue damage due to the cyclic loading and predicts the approximate number of missions a component can endure before failing.

  14. Mass loading effect of shock accelerometers

    Science.gov (United States)

    Wu, Lixue; Wong, George S. K.; Hanes, Peter; Ohm, Won-Suk

    2005-04-01

    Mass loading affects the sensitivity of an accelerometer. The mass loading effect can be corrected using mass loading correction curves published by manufacturers. These curves, however, are only applicable to the sinusoidal acceleration below 500 m/s2. The mass loading effect on the sensitivity of an Endevco 2270 accelerometer in shock calibration, from 500 m/s2 and up, was investigated using a laser vibrometer. A new method for conversion of a velocity signal to an acceleration signal was developed. With this method, the sensitivities of the above accelerometer for different mass loads at different shock levels were measured. The mass loading effect in shock calibration for this accelerometer was then obtained. The limitations of the sensitivity measurements were also studied. The variance of the measured sensitivity was mainly due to the resolution limitation (8-bit) of the A/D converter in the digital oscilloscope. A correlation matching algorithm was then developed that utilizes the similarity between the measured acceleration signal and that converted from the velocity signal to further improve the resolution of the digital oscilloscope.

  15. Fatigue life prediction under service load considering strengthening effect of loads below fatigue limit

    Science.gov (United States)

    Zhao, Lihui; Zheng, Songlin; Feng, Jinzhi

    2014-11-01

    Lightweight design requires an accurate life prediction for structures and components under service loading histories. However, predicted life with the existing methods seems too conservative in some cases, leading to a heavy structure. Because these methods are established on the basis that load cycles would only cause fatigue damage, ignore the strengthening effect of loads. Based on Palmgren-Miner Rule (PMR), this paper introduces a new method for fatigue life prediction under service loadings by taking into account the strengthening effect of loads below the fatigue limit. In this method, the service loadings are classified into three categories: damaging load, strengthening load and none-effect load, and the process for fatigue life prediction is divided into two stages: stage I and stage II, according to the best strengthening number of cycles. During stage I, fatigue damage is calculated considering both the strengthening and damaging effect of load cycles. While during stage II, only the damaging effect is considered. To validate this method, fatigue lives of automobile half shaft and torsion beam rear axle are calculated based on the new method and traditional methods, such as PMR and Modified Miner Rule (MMR), and fatigue tests of the two components are conducted under service loading histories. The tests results show that the percentage errors of the predicted life with the new method to mean life of tests for the two components are -3.78% and -1.76% separately, much lesser than that with PMR and MMR. By considering the strengthening effect of loads below the fatigue limit, the new method can significantly improve the accuracy for fatigue life prediction. Thus lightweight design can be fully realized in the design stage.

  16. Evaluation of load rejection to house load test at 50% power for UCN 3

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Chang Gyun; Sohn, Suk Whun; Sohn, Jong Joo; Seo, Jong Tae; Lee, Sang Keun [KOPEC, Yongin (Korea, Republic of); Kim, Yong Sung; Nam, Kyu Won; Jung, Yang Mook; Chae, Kyeong Sik; Koh, Bum Jae; Oh, Chul Sung; Park, Hee Chool [KEPCO, Seoul (Korea, Republic of)

    1998-05-01

    The Load Rejection to House Load test at 50% power was successfully performed during the UCN 3 PAT period. In this test, all plant control systems automatically controlled the plant from 50% power to house load operation mode. The KISPAC code, which was used in the performance analysis during the design process of UCN 3 and 4, predictions of the test agreed with the measured data demonstrating the validity of the code as well as completeness of the plant design.

  17. Design and analysis of a novel mechanical loading machine for dynamic in vivo axial loading.

    Science.gov (United States)

    Macione, James; Nesbitt, Sterling; Pandit, Vaibhav; Kotha, Shiva

    2012-02-01

    This paper describes the construction of a loading machine for performing in vivo, dynamic mechanical loading of the rodent forearm. The loading machine utilizes a unique type of electromagnetic actuator with no mechanically resistive components (servotube), allowing highly accurate loads to be created. A regression analysis of the force created by the actuator with respect to the input voltage demonstrates high linear correlation (R(2) = 1). When the linear correlation is used to create dynamic loading waveforms in the frequency (0.5-10 Hz) and load (1-50 N) range used for in vivo loading, less than 1% normalized root mean square error (NRMSE) is computed. Larger NRMSE is found at increased frequencies, with 5%-8% occurring at 40 Hz, and reasons are discussed. Amplifiers (strain gauge, linear voltage displacement transducer (LVDT), and load cell) are constructed, calibrated, and integrated, to allow well-resolved dynamic measurements to be recorded at each program cycle. Each of the amplifiers uses an active filter with cutoff frequency at the maximum in vivo loading frequencies (50 Hz) so that electronic noise generated by the servo drive and actuator are reduced. The LVDT and load cell amplifiers allow evaluation of stress-strain relationships to determine if in vivo bone damage is occurring. The strain gauge amplifier allows dynamic force to strain calibrations to occur for animals of different sex, age, and strain. Unique features are integrated into the loading system, including a weightless mode, which allows the limbs of anesthetized animals to be quickly positioned and removed. Although the device is constructed for in vivo axial bone loading, it can be used within constraints, as a general measurement instrument in a laboratory setting.

  18. Mapping of Critical Loads and Critical Load Exceedances in the Killarney Provincial Park, Ontario, Canada

    OpenAIRE

    Hindar, A.; Henriksen, A.

    1998-01-01

    Calculations of critical loads for inputs of strong acids to lakes and exceedances of critical load can be a useful tool for the management of polluted areas. In Sudbury, Canada, large emissions of sulfur dioxide have resulted in widespread lake acidification in parts of northeastern Canada. Due to its vicinity to Sudbury, extensive lake acidification and fish loss has occurred in the Killarney Provincial Park. We have linked measured water quality to critical loads and strong acid deposition...

  19. The Optimal Choice of Promotional Vehicles: Front-Loaded or Rear-Loaded Incentives?

    OpenAIRE

    Z. John Zhang; Aradhna Krishna; Sanjay K. Dhar

    2000-01-01

    We examine the key factors that influence a firm's decision whether to use front-loaded or rear-loaded incentives. When using price packs, direct mail coupons, FSI coupons or peel-off coupons, consumers obtain an immediate benefit upon purchase or a front-loaded incentive. However, when buying products with in-pack coupons or products affiliated with loyalty programs, promotion incentives are obtained on the next purchase occasion or later, i.e., a rear-loaded incentive. Our analysis shows th...

  20. Static ice loads on hydro-electric structures: ice load monographs: Volume 1: Final report

    Energy Technology Data Exchange (ETDEWEB)

    Comfort, G.; Abdelnour, R.; Gong, Y.; Dinovitzer, A.

    1996-07-01

    Ice loads on hydro-electric structures were measured during a four-year field program. Loads were measured at Hydro-Quebec`s Paugan dam, Ontario Hydro`s Arnprior and Otto Holden dams, and in a large outdoor basin at the National Research Council (NRC) during one winter. Ice loads were measured in the reservoir ice sheet, near the concrete face of the dam, and near the gate and pier of the Paugan dam. Ice stresses were measured continuously by stressmeters that were deployed in the ice. Loads at the Paugan dam and the NRC basin resulted mostly from ice temperature changes. The loads at the Arnprior and Otto Holden dams were produced by a combination of ice temperature and water level changes. The collected data was analyzed in detail and efforts were made to improve techniques for predicting ice loads. Significant progress was made towards the development of detailed, quantitative understanding of static ice loads on hydro-electric structures, and the factors controlling them. However, the ice load predictors are subject to a number of limitations and further work is required before changes to design practices can be recommended with confidence. More field data collection would also improve the definition of loads arising from a combination of water level and ice temperature changes. Additional numerical analyses was also recommended to better define the effects of ice confinement. Appendices were published separately in volume 2 of this report. 43 refs., 18 tabs., 96 figs.

  1. Application of PSAT to Load Flow Analysis with STATCOM under Load Increase Scenario and Line Contingencies

    Science.gov (United States)

    Telang, Aparna S.; Bedekar, P. P.

    2017-09-01

    Load flow analysis is the initial and essential step for any power system computation. It is required for choosing better options for power system expansion to meet with ever increasing load demand. Implementation of Flexible AC Transmission System (FACTS) device like STATCOM, in the load flow, which is having fast and very flexible control, is one of the important tasks for power system researchers. This paper presents a simple and systematic approach for steady state power flow calculations with FACTS controller, static synchronous compensator (STATCOM) using command line usage of MATLAB tool-power system analysis toolbox (PSAT). The complexity of MATLAB language programming increases due to incorporation of STATCOM in an existing Newton-Raphson load flow algorithm. Thus, the main contribution of this paper is to show how command line usage of user friendly MATLAB tool, PSAT, can extensively be used for quicker and wider interpretation of the results of load flow with STATCOM. The novelty of this paper lies in the method of applying the load increase pattern, where the active and reactive loads have been changed simultaneously at all the load buses under consideration for creating stressed conditions for load flow analysis with STATCOM. The performance have been evaluated on many standard IEEE test systems and the results for standard IEEE-30 bus system, IEEE-57 bus system, and IEEE-118 bus system are presented.

  2. 2006 Pacific Northwest Loads and Resources Study.

    Energy Technology Data Exchange (ETDEWEB)

    United States. Bonneville Power Administration.

    2006-03-01

    The Pacific Northwest Loads and Resources Study (White Book), which is published annually by the Bonneville Power Administration (BPA), establishes one of the planning bases for supplying electricity to customers. The White Book contains projections of regional and Federal system load and resource capabilities, along with relevant definitions and explanations. The White Book also contains information obtained from formalized resource planning reports and data submittals including those from individual utilities, the Northwest Power and Conservation Council (Council), and the Pacific Northwest Utilities Conference Committee (PNUCC). The White Book is not an operational planning guide, nor is it used for determining BPA revenues, although the database that generates the data for the White Book analysis contributes to the development of BPA's inventory and ratemaking processes. Operation of the Federal Columbia River Power System (FCRPS) is based on a set of criteria different from that used for resource planning decisions. Operational planning is dependent upon real-time or near-term knowledge of system conditions that include expectations of river flows and runoff, market opportunities, availability of reservoir storage, energy exchanges, and other factors affecting the dynamics of operating a power system. The load resource balance of both the Federal system and the region is determined by comparing resource availability to an expected level of total retail electricity consumption. Resources include projected energy capability plus contract purchases. Loads include a forecast of retail obligations plus contract obligations. Surplus energy is available when resources are greater than loads. This surplus energy could be marketed to increase revenues. Energy deficits occur when resources are less than loads. These energy deficits will be met by any combination of the following: better-than-critical water conditions, demand-side management and conservation

  3. Multilayered elastic analysis formulation for surface moment loading

    CSIR Research Space (South Africa)

    Maina, JW

    2006-01-01

    Full Text Available into consideration surface moment loading. GOVERNING EQUATIONS The governing equations may be presented by using cylindrical coordinate system and assume that a circular load, with radius a , is acting on the pavement surface and the magnitude of the load varies... of Equation (1a) is the uniformly distributed vertical load, while the second item represents the load, which is anti-symmetric about the y - axis. The loading distribution obtained from Equation (1a) is a sum of uniformly distributed load and the load...

  4. Laterally cyclic loading of monopile in dense sand

    DEFF Research Database (Denmark)

    Klinkvort, Rasmus Tofte; Hededal, Ole; Svensson, M.

    2011-01-01

    the loading conditions. In these tests the load conditions are controlled by two load characteristics, one controlling the level of the cyclic loading and one controlling the characteristic of the cyclic loading. The centrifuge tests were performed in dense dry sand on a pile with prototype dimensions...... used for wind turbine foundation. This is important in order to get the right failure mechanism in the sand. The load frame is controlled with a feedback system which enables force controlled load series. A total number of 8 tests have been carried. In all of the tests, the pile was loaded with 500...

  5. Load forecasting method considering temperature effect for distribution network

    Directory of Open Access Journals (Sweden)

    Meng Xiao Fang

    2016-01-01

    Full Text Available To improve the accuracy of load forecasting, the temperature factor was introduced into the load forecasting in this paper. This paper analyzed the characteristics of power load variation, and researched the rule of the load with the temperature change. Based on the linear regression analysis, the mathematical model of load forecasting was presented with considering the temperature effect, and the steps of load forecasting were given. Used MATLAB, the temperature regression coefficient was calculated. Using the load forecasting model, the full-day load forecasting and time-sharing load forecasting were carried out. By comparing and analyzing the forecast error, the results showed that the error of time-sharing load forecasting method was small in this paper. The forecasting method is an effective method to improve the accuracy of load forecasting.

  6. Distributed dynamic load on composite laminates

    Science.gov (United States)

    Langella, A.; Lopresto, V.; Caprino, G.

    2016-05-01

    An experimental activity conducted in order to assess the impact behavior at room and low temperature of carbon fibre in vinylester resin laminates used in the shipbuilding industry, was reported. The conditions which reproduce the impact of a hull at low temperature with a solid body suspended in the water was reproduced. A test equipment was designed and realized to reproduce the real material behaviour in water to obtain a load distribution on the entire surface of the specimen. The results were obtained impacting the laminates placed between the cilyndrical steel impactor and a bag containing water. A falling weight machine, equipped with an instrumented steel impactor and a thermal chamber, was adopted for the experimental tests. The impact behaviour in hostile environments was compared to the behaviour at room temperature and the data obtained under distributed load conditions were compared with the results from concentrated loads: a completely different behaviour was observed between the two different loading conditions in terms of load-displacement curve. The effect of the impact on the laminates has been related with the delaminations, evaluated by ultrasonic scanning, and the indentation.

  7. Power transformer additional load losses separation procedure

    Directory of Open Access Journals (Sweden)

    Kostić Miloje M.

    2011-01-01

    Full Text Available The proposed procedure is based on the fact that total transformer losses (PLL1,n, determined by short circuit test, can be separated into two components: the eddy current losses in the windings (PEC1,n and stray flux losses (PSL1,n in iron parts of construction as well as in the transformer tank walls. The total additional load losses, PLLd1 and PLLdh, are determined by short circuit test results, conducted at rated frequency (f1 and at increased harmonic frequency (fh=h*f1. Using so obtained total additional load losses, PLLd1 and PLLdh, which can be expressed in the form PLLdh=PEC1,n*h2 + PSL1,n*h, the corresponding rate additional load losses values PEC1,n and PSL1,n are derived. At the end, for given load with predefined high harmonics content, (Ih/I1n, relative to rated current, the total additional load losses value ΣPLLdh > PLLd1, is found. In such a way all harmonics up to hmax are taken into account.

  8. Concrete structures under impact loading: general aspects

    Directory of Open Access Journals (Sweden)

    Cornelia Baeră

    2016-09-01

    Full Text Available Dynamic loading conditions distress the structural integrity of a structure differently than the static ones. Such actions transfer high rate strains and instant energy waves to the structure, inducing the possibility of imminent collapse and casualties as a direct consequence. In the latest years, considering the dramatic increase of terrorist threats and global warming, the structural safety criteria imply more than ever the need to withstand this kind of loading (e.g., missiles and blast, projectiles, strong winds, tornados and earthquakes in addition to the static ones. The aim of this paper is to provide a general overview with regard to impact loading in terms of defining the phenomenon from physical and mechanical perspective, its complex local or global effect on the targeted structure, relevant material characteristics, main research approaches, namely theoretical studies and experimental procedures developed for improving the predictability of the dynamic loads and their effects. New directions in developing superior cementitious composites, with better characteristics in terms of dynamic loading performance are also emphasized.

  9. Short term load forecasting: two stage modelling

    Directory of Open Access Journals (Sweden)

    SOARES, L. J.

    2009-06-01

    Full Text Available This paper studies the hourly electricity load demand in the area covered by a utility situated in the Seattle, USA, called Puget Sound Power and Light Company. Our proposal is put into proof with the famous dataset from this company. We propose a stochastic model which employs ANN (Artificial Neural Networks to model short-run dynamics and the dependence among adjacent hours. The model proposed treats each hour's load separately as individual single series. This approach avoids modeling the intricate intra-day pattern (load profile displayed by the load, which varies throughout days of the week and seasons. The forecasting performance of the model is evaluated in similiar mode a TLSAR (Two-Level Seasonal Autoregressive model proposed by Soares (2003 using the years of 1995 and 1996 as the holdout sample. Moreover, we conclude that non linearity is present in some series of these data. The model results are analyzed. The experiment shows that our tool can be used to produce load forecasting in tropical climate places.

  10. Phloem Loading through Plasmodesmata: A Biophysical Analysis.

    Science.gov (United States)

    Comtet, Jean; Turgeon, Robert; Stroock, Abraham D

    2017-10-01

    In many species, Suc en route out of the leaf migrates from photosynthetically active mesophyll cells into the phloem down its concentration gradient via plasmodesmata, i.e. symplastically. In some of these plants, the process is entirely passive, but in others phloem Suc is actively converted into larger sugars, raffinose and stachyose, and segregated (trapped), thus raising total phloem sugar concentration to a level higher than in the mesophyll. Questions remain regarding the mechanisms and selective advantages conferred by both of these symplastic-loading processes. Here, we present an integrated model-including local and global transport and kinetics of polymerization-for passive and active symplastic loading. We also propose a physical model of transport through the plasmodesmata. With these models, we predict that (1) relative to passive loading, polymerization of Suc in the phloem, even in the absence of segregation, lowers the sugar content in the leaf required to achieve a given export rate and accelerates export for a given concentration of Suc in the mesophyll and (2) segregation of oligomers and the inverted gradient of total sugar content can be achieved for physiologically reasonable parameter values, but even higher export rates can be accessed in scenarios in which polymers are allowed to diffuse back into the mesophyll. We discuss these predictions in relation to further studies aimed at the clarification of loading mechanisms, fitness of active and passive symplastic loading, and potential targets for engineering improved rates of export. © 2017 American Society of Plant Biologists. All Rights Reserved.

  11. Fruit load governs transpiration of olive trees

    Science.gov (United States)

    Bustan, Amnon; Dag, Arnon; Yermiyahu, Uri; Erel, Ran; Presnov, Eugene; Agam, Nurit; Kool, Dilia; Iwema, Joost; Zipori, Isaac; Ben-Gal, Alon

    2016-01-01

    We tested the hypothesis that whole-tree water consumption of olives (Olea europaea L.) is fruit load-dependent and investigated the driving physiological mechanisms. Fruit load was manipulated in mature olives grown in weighing-drainage lysimeters. Fruit was thinned or entirely removed from trees at three separate stages of growth: early, mid and late in the season. Tree-scale transpiration, calculated from lysimeter water balance, was found to be a function of fruit load, canopy size and weather conditions. Fruit removal caused an immediate decline in water consumption, measured as whole-plant transpiration normalized to tree size, which persisted until the end of the season. The later the execution of fruit removal, the greater was the response. The amount of water transpired by a fruit-loaded tree was found to be roughly 30% greater than that of an equivalent low- or nonyielding tree. The tree-scale response to fruit was reflected in stem water potential but was not mirrored in leaf-scale physiological measurements of stomatal conductance or photosynthesis. Trees with low or no fruit load had higher vegetative growth rates. However, no significant difference was observed in the overall aboveground dry biomass among groups, when fruit was included. This case, where carbon sources and sinks were both not limiting, suggests that the role of fruit on water consumption involves signaling and alterations in hydraulic properties of vascular tissues and tree organs. PMID:26802540

  12. Modular load flow for restructured power systems

    CERN Document Server

    Hariharan, M V; Gupta, Pragati P

    2016-01-01

    In the subject of power systems, authors felt that a re-look is necessary at some conventional methods of analysis. In this book, the authors have subjected the time-honoured load flow to a close scrutiny. Authors have discovered and discussed a new load flow procedure – Modular Load Flow. Modular Load Flow explores use of power – a scalar – as source for electrical circuits which are conventionally analysed by means of phasors – the ac voltages or currents. The method embeds Kirchhoff’s circuit laws as topological property into its scalar equations and results in a unique wonderland where phase angles do not exist! Generators are shown to have their own worlds which can be superimposed to obtain the state of the composite power system. The treatment is useful in restructured power systems where stakeholders and the system operators may desire to know individual generator contributions in line flows and line losses for commercial reasons. Solution in Modular Load Flow consists of explicit expression...

  13. Power-load curve in trained sprinters.

    Science.gov (United States)

    Alcaraz, Pedro E; Romero-Arenas, Salvador; Vila, Helena; Ferragut, Carmen

    2011-11-01

    The levels of lower-limb strength and power can distinguish between athletes of different levels in a number of sports, specifically in sprinting. In this sense, the purposes of this study were (a) to define the power–load curve in a modified half squat machine in trained sprinters in the competitive cycle and (b) to correlate the peak power (PP) production with 60-m sprint performance. In this sense, a cross-sectional study was carried out with 10 national level sprinters. After the calculation of 1 repetition maximum (1RM) of the participants, a progressive test, which consisted of moving loads of 30, 45, 60, 70, and 80% of the 1RM as quickly as possible in the concentric phase, was performed. It was found that PP occurred at 60% of 1RM. The power output with all loads was not significantly different (p ≤ 0.05) from each other. No significant correlations were found between 60-m performance and PP with the different loads. Therefore, we may conclude that the sprinters of national level analyzed present values of PP output, in the competitive period, near to 60% of 1RM in the half squat exercise; however, this power is not significantly different from the other loads.

  14. Cognitive load measurement as a means to advance cognitive load theory

    NARCIS (Netherlands)

    Paas, F.; Tuovinen, J.E.; Tabbers, H.; van Gerven, P.W.M.

    2003-01-01

    This paper discusses cognitive load measurement techniques with regard to their contribution to cognitive load theory (CLT). CLT is concerned with the design of instructional methods that efficiently use people's limited cognitive processing capacity to apply acquired knowledge and skills to new

  15. Fractographic study of epoxy fractured under mode I loading and mixed mode I/III loading

    Energy Technology Data Exchange (ETDEWEB)

    Ren, Fei [ORNL; Wang, Jy-An John [ORNL; Bertelsen, Williams D. [Gougeon Brothers, Inc.

    2011-01-01

    Fiber reinforced polymeric composite materials are widely used in structural components such as wind turbine blades, which are typically subject to complicated loading conditions. Thus, material response under mixed mode loading is of great significance to the reliability of these structures. Epoxy is a thermosetting polymer that is currently used in manufacturing wind turbine blades. The fracture behavior of epoxy is relevant to the mechanical integrity of the wind turbine composite materials. In this study, a novel fracture testing methodology, the spiral notch torsion test (SNTT), was applied to study the fracture behavior of an epoxy material. SNTT samples were tested using either monotonic loading or cyclic loading, while both mode I and mixed mode I/III loading conditions were used. Fractographic examination indicated the epoxy samples included in this study were prone to mode I failure even when the samples were subject to mixed mode loading. Different fatigue precracks were observed on mode I and mixed mode samples, i.e. precracks appeared as a uniform band under mode I loading, and a semi-ellipse under mixed mode loading. Fracture toughness was also estimated using quantitative fractography.

  16. System ID Modern Control Algorithms for Active Aerodynamic Load Control and Impact on Gearbox Loading

    NARCIS (Netherlands)

    Berg, D.; Wilson, D.; Resor, B.; Berg, J.; Barlas, J.; Crowther, A.; Halse, C.

    2010-01-01

    Prior work on active aerodynamic load control (AALC) of wind turbine blades has demonstrated that appropriate use of this technology has the potential to yield significant reductions in blade loads, leading to a decrease in wind cost of energy. While the general concept of AALC is usually discussed

  17. Method and device for loading packed goods using an intermediate load unit

    NARCIS (Netherlands)

    Reijnen, R.; Ross, L.H.A.; Houlleberghs, B.R.Y.; Naber, J.; Van der Meulen, R.J.R.

    2009-01-01

    The invention relates to a device for loading packed goods into a transport unit (8b), the device comprising an orientation unit for orienting each packed good in a predetermined direction, means for transferring the packed goods in the order of a predetermined loading sequence to the orientation

  18. A Microstructural Study of Load Distribution in Cartilage: A Comparison of Stress Relaxation versus Creep Loading

    Directory of Open Access Journals (Sweden)

    Ashvin Thambyah

    2015-01-01

    Full Text Available The compressive response of articular cartilage has been extensively investigated and most studies have focussed largely on the directly loaded matrix. However, especially in relation to the tissue microstructure, less is known about load distribution mechanisms operating outside the directly loaded region. We have addressed this issue by using channel indentation and DIC microscopy techniques that provide visualisation of the matrix microstructural response across the regions of both direct and nondirect loading. We hypothesise that, by comparing the microstructural response following stress relaxation and creep compression, new insights can be revealed concerning the complex mechanisms of load bearing. Our results indicate that, with stress relaxation, the initial mode of stress decay appears to primarily involve relaxation of the surface layer. In the creep loading protocol, the main mode of stress release is a lateral distribution of load via the mid matrix. While these two modes of stress redistribution have a complex relationship with the zonally differentiated tissue microstructure and the depth of strain, four mechanostructural mechanisms are proposed to describe succinctly the load responses observed.

  19. Bit Loading Algorithms for Cooperative OFDM Systems

    Directory of Open Access Journals (Sweden)

    Bo Gui

    2007-12-01

    Full Text Available We investigate the resource allocation problem for an OFDM cooperative network with a single source-destination pair and multiple relays. Assuming knowledge of the instantaneous channel gains for all links in the entire network, we propose several bit and power allocation schemes aiming at minimizing the total transmission power under a target rate constraint. First, an optimal and efficient bit loading algorithm is proposed when the relay node uses the same subchannel to relay the information transmitted by the source node. To further improve the performance gain, subchannel permutation, in which the subchannels are reallocated at relay nodes, is considered. An optimal subchannel permutation algorithm is first proposed and then an efficient suboptimal algorithm is considered to achieve a better complexity-performance tradeoff. A distributed bit loading algorithm is also proposed for ad hoc networks. Simulation results show that significant performance gains can be achieved by the proposed bit loading algorithms, especially when subchannel permutation is employed.

  20. Integrated microelectromechanical gyroscope under shock loads

    Science.gov (United States)

    Nesterenko, T. G.; Koleda, A. N.; Barbin, E. S.

    2018-01-01

    The paper presents a new design of a shock-proof two-axis microelectromechanical gyroscope. Without stoppers, the shock load enables the interaction between the silicon sensor elements. Stoppers were installed in the gyroscope to prevent the contact interaction between electrodes and spring elements with fixed part of the sensor. The contact of stoppers occurs along the plane, thereby preventing the system from serious contact stresses. The shock resistance of the gyroscope is improved by the increase in its eigenfrequency at which the contact interaction does not occur. It is shown that the shock load directed along one axis does not virtually cause the movement of sensing elements along the crosswise axes. Maximum stresses observed in the proposed gyroscope at any loading direction do not exceed the value allowable for silicon.

  1. Free Material Design with Multiple Load Cases

    DEFF Research Database (Denmark)

    Pedersen, Pauli; Pedersen, Niels Leergaard

    2012-01-01

    Multiple load cases and the consideration of strength is a reality that most structural designs are exposed to. Improved possibility to produce specific materials, say by fiber lay-up, put focus on research on free material optimization. A formulation for such design problems together with a prac......Multiple load cases and the consideration of strength is a reality that most structural designs are exposed to. Improved possibility to produce specific materials, say by fiber lay-up, put focus on research on free material optimization. A formulation for such design problems together...... with a practical recursive design procedure is presented and illustrated with examples. The presented finite element analysis involve many elements as well as many load cases. Separating the local amount of material from a description with unit trace for the local anisotropy, gives the free materials formulation...

  2. Design Load Basis for Offshore Wind turbines

    DEFF Research Database (Denmark)

    Natarajan, Anand; Hansen, Morten Hartvig; Wang, Shaofeng

    2016-01-01

    DTU Wind Energy is not designing and manufacturing wind turbines and does therefore not need a Design Load Basis (DLB) that is accepted by a certification body. However, to assess the load consequences of innovative features and devices added to existing offshore turbine concepts or new offshore...... turbine concept developed in our research, it is useful to have a full DLB that follows the current design standard and is representative of a general DLB used by the industry. It will set a standard for the offshore wind turbine design load evaluations performed at DTU Wind Energy, which is aligned...... with the challenges faced by the industry and therefore ensures that our research continues to have a strong foundation in this interaction. Furthermore, the use of a full DLB that follows the current standard can improve and increase the feedback from the research at DTU Wind Energy to the international...

  3. Managing the Training Load in Adolescent Athletes.

    Science.gov (United States)

    Murray, Andrew

    2017-04-01

    While historically adolescents were removed from their parents to prepare to become warriors, this process repeats itself in modern times but with the outcome being athletic performance. This review considers the process of developing athletes and managing load against the backdrop of differing approaches of conserving and maximizing the talent available. It acknowledges the typical training "dose" that adolescent athletes receive across a number of sports and the typical "response" when it is excessive or not managed appropriately. It also examines the best approaches to quantifying load and injury risk, acknowledging the relative strengths and weaknesses of subjective and objective approaches. Making evidence-based decisions is emphasized, while the appropriate monitoring techniques are determined by both the sporting context and individual situation. Ultimately a systematic approach to training-load monitoring is recommended for adolescent athletes to both maximize their athletic development and allow an opportunity for learning, reflection, and enhancement of performance knowledge of coaches and practitioners.

  4. Contact Sliding under Relatively Low Loads

    Directory of Open Access Journals (Sweden)

    Kyeong Hee Kang

    2011-01-01

    Full Text Available ZnO nanowires have received much interest owing to their particular structural and piezoelectric properties. For widespread application of ZnO nanowires in various nanotechnologies, the mechanical reliability of the nanowires should be assessed. In this paper, the damage characteristics of vertically grown ZnO nanowires due to contact sliding against a 2 mm diameter steel ball under relatively low loads were investigated. Frictional behavior and wear characteristics of the specimens were assessed. Furthermore, contact sliding tests were performed inside an SEM to monitor the progression of damage of the nanowires. It was found that the friction coefficient was about 0.35 under all loads while the damage characteristics of the nanowires were quite different for each load. The large diameter nanowires tended to fracture earlier than the small diameter nanowires. Wear tests performed inside the SEM confirmed the surface damage characteristics observed during the friction tests.

  5. Lower head integrity under steam explosion loads

    Energy Technology Data Exchange (ETDEWEB)

    Theofanous, T.G.; Yuen, W.W.; Angelini, S.; Freeman, K.; Chen, X.; Salmassi, T. [Center for Risk Studies and Safety, Univ. of California, Santa Barbara, CA (United States); Sienicki, J.J.

    1998-01-01

    Lower head integrity under steam explosion loads in an AP600-like reactor design is considered. The assessment is the second part of an evaluation of the in-vessel retention idea as a severe accident management concept, the first part (DOE/ID-10460) dealing with thermal loads. The assessment is conducted in terms of the Risk Oriented Accident Analysis Methodology (ROAAM), and includes the comprehensive evaluation of all relevant severe accident scenarios, melt conditions and timing of release from the core region, fully 3D mixing and explosion wave dynamics, and lower head fragility under local, dynamic loading. All of these factors and brought together in a ROAAM Probabilistic Framework to evaluate failure likelihood. The conclusion is that failure is `physically unreasonable`. (author)

  6. Radio Frequency Power Load and Associated Method

    Science.gov (United States)

    Srinivasan, V. Karthik (Inventor); Freestone, Todd M. (Inventor); Sims, William Herbert, III (Inventor)

    2014-01-01

    A radio frequency power load and associated method. A radio frequency power load apparatus may include a container with an ionized fluid therein. The apparatus may include one conductor immersed in a fluid and another conductor electrically connected to the container. A radio frequency transmission system may include a radio frequency transmitter, a radio frequency amplifier connected to the transmitter and a radio frequency power load apparatus connected to the amplifier. The apparatus may include a fluid having an ion source therein, one conductor immersed in a fluid, and another conductor electrically connected to the container. A method of dissipating power generated by a radio frequency transmission system may include constructing a waveguide with ionized fluid in a container and connecting the waveguide to an amplifier of the transmission system.

  7. Bit Loading Algorithms for Cooperative OFDM Systems

    Directory of Open Access Journals (Sweden)

    Gui Bo

    2008-01-01

    Full Text Available Abstract We investigate the resource allocation problem for an OFDM cooperative network with a single source-destination pair and multiple relays. Assuming knowledge of the instantaneous channel gains for all links in the entire network, we propose several bit and power allocation schemes aiming at minimizing the total transmission power under a target rate constraint. First, an optimal and efficient bit loading algorithm is proposed when the relay node uses the same subchannel to relay the information transmitted by the source node. To further improve the performance gain, subchannel permutation, in which the subchannels are reallocated at relay nodes, is considered. An optimal subchannel permutation algorithm is first proposed and then an efficient suboptimal algorithm is considered to achieve a better complexity-performance tradeoff. A distributed bit loading algorithm is also proposed for ad hoc networks. Simulation results show that significant performance gains can be achieved by the proposed bit loading algorithms, especially when subchannel permutation is employed.

  8. Phloem loading through plasmodesmata: a biophysical analysis

    CERN Document Server

    Comtet, Jean; Stroock, Abraham D

    2016-01-01

    In many species, sucrose en route out of the leaf migrates from photosynthetically active mesophyll cells into the phloem down its concentration gradient via plasmodesmata, i.e., symplastically. In some of these plants the process is entirely passive, but in others phloem sucrose is actively converted into larger sugars, raffinose and stachyose, and segregated (trapped), thus raising total phloem sugar concentration to a level higher than in the mesophyll. Questions remain regarding the mechanisms and selective advantages conferred by both of these symplastic loading processes. Here we present an integrated model - including local and global transport and the kinetics of oligomerization - for passive and active symplastic loading. We also propose a physical model of transport through the plasmodesmata. With these models, we predict that: 1) relative to passive loading, oligomerization of sucrose in the phloem, even in the absence of segregation, lowers the sugar content in the leaf required to achieve a given...

  9. Compensator configurations for load currents' symmetrization

    Science.gov (United States)

    Rusinaru, D.; Manescu, L. G.; Dinu, R. C.

    2016-02-01

    This paper approaches aspects regarding the mitigation effects of asymmetries in 3-phase 3-wire networks. The measure consisting in connecting of load current symmetrization devices at the load coupling point is presented. A time-variation of compensators parameters is determined as a function of the time-recorded electrical values. The general sizing principle of the load current symmetrization reactive components is based on a simple equivalent model of the unbalanced 3-phase loads. By using these compensators a certain control of the power components transits is ensured in the network. The control is based on the variations laws of the compensators parameters as functions of the recorded electrical values: [B] = [T]·[M]. The link between compensator parameters and measured values is ensured by a transformation matrix [T] for each operation conditions of the supply network. Additional conditions for improving of energy and efficiency performance of the compensator are considered: i.e. reactive power compensation. The compensator sizing algorithm was implemented into a MATLAB environment software, which generate the time-evolution of the parameters of load current symmetrization device. The input data of application takes into account time-recording of the electrical values. By using the compensator sizing software, some results were achieved for the case of a consumer connected at 20 kV busbar of a distribution substation, during 24 hours measurement session. Even the sizing of the compensators aimed some additional network operation aspects (power factor correction) correlated with the total or major load symmetrizations, the harmonics aspects of the network values were neglected.

  10. Laguna Verde annulus pressurization loads evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Castaneda, M. A.; Cruz, M. A.; Cardenas, J. B.; Vargas, A.; Cruz, H. J.; Mercado, J. J., E-mail: miguel.castaneda01@cfe.gob.m [Comision Federal de Electricidad, Central Nucleoelectrica de Laguna Verde, Km. 42.5 Carretera Cardel-Nautla, Veracruz (Mexico)

    2010-10-15

    Annulus pressurization, jet impingement, pipe whip restraint and jet thrust are phenomena related to postulated pipe ruptures. A postulated pipe rupture at the weld between recirculation, or feedwater piping and a reactor nozzle safe end, will lead to a high flow rate of flashing water/steam mixture into the annulus between the reactor pressure vessel and the biological shield wall. The total effect of the vessel and pipe inventory blowdown from the break being postulated must be accounted for in the evaluation. A recirculation line break will give rise to an angular dependent short term pressure differential around the vessel, followed by a longer term pressure buildup in the annulus. A recirculation line postulated rupture may not produce worst case conditions and reference to time intervals for only the recirculation break should be treated superficially. A postulated rupture of the feedwater piping may produce the extreme case for determining: 1) the shield wall and reactor vessel to pedestal interactions, 2) loading on the reactor vessel internals, or 3) responses for the balance of piping attached to the vessel. Recently it was identified a potential issue regarding the criteria used to determine which cases were evaluated for Annulus Pressurization (A P) loads for new loads plants. The original A P loads methodology in the late 1970 and early 1980 years separated the mass/energy release calculation from the structural response calculation based on the implicit assumption that the maximum overall mass/energy release will result in maximizing the structural response and corresponding stresses on the reactor pressure vessel, internals, and containment structures. This process did not consider the dynamic response in the primary and secondary safety related structures, components and equipment. Consequently, the A P loads used as input for design adequacy evaluations of Nuclear Steam Supply System safety related components for new loads plants might have

  11. Reduction of date microbial load with ozone

    Science.gov (United States)

    Farajzadeh, Davood; Qorbanpoor, Ali; Rafati, Hasan; Isfeedvajani, Mohsen Saberi

    2013-01-01

    Background: Date is one of the foodstuffs that are produced in tropical areas and used worldwide. Conventionally, methyl bromide and phosphine are used for date disinfection. The toxic side effects of these usual disinfectants have led food scientists to consider safer agents such as ozone for disinfection, because food safety is a top priority. The present study was performed to investigate the possibility of replacing common conventional disinfectants with ozone for date disinfection and microbial load reduction. Materials and Methods: In this experimental study, date samples were ozonized for 3 and 5 hours with 5 and 10 g/h concentrations and packed. Ozonized samples were divided into two groups and kept in an incubator which was maintained at 25°C and 40°C for 9 months. During this period, every 3 month, microbial load (bacteria, mold, and yeast) were examined in ozonized and non-ozonized samples. Results: This study showed that ozonization with 5 g/h for 3 hours, 5 g/h for 5 hours, 10 g/h for 3 hours, and 10 g/h for 5 hours leads to about 25%, 25%, 53%, and 46% reduction in date mold and yeast load and about 6%, 9%, 76%, and 74.7% reduction in date bacterial load at baseline phase, respectively. Appropriate concentration and duration of ozonization for microbial load reduction were 10 g/h and 3 hours. Conclusion: Date ozonization is an appropriate method for microbial load reduction and leads to an increase in the shelf life of dates. PMID:24124432

  12. INFLUENCE OF MOVING LOADS ON CURVED BRIDGES

    OpenAIRE

    Thamer A. Z*, Jabbbar S. A

    2016-01-01

    The behavior of a curved slab bridge decks with uniform thickness under moving load is investigated in this study. Three radii of curvature "R" are used (25, 50 and 75m) along with the straight bridge, R = ∞. The decks are simply supported or clamped along the radial edges and free at the circular edges. The AASHTO[1] standard axle load of the truck H20-44 is used and assumed to move in three track positions on the bridge. The finite element method is employed for the analysis and the ANSYS 5...

  13. Practical Hydrogen Loading of Air Silica Fibres

    DEFF Research Database (Denmark)

    Sørensen, Henrik Rokkjær; Jensen, Jesper Bevensee; Jensen, Jesper Bo Damm

    2005-01-01

    A method for hydrogen-loading air-silica optical fibres has been developed allowing out-diffusion times comparable to standard step-index fibres. Examples of the first grating written in Ge-doped air-silica fibres using a 266nm UV-laser are shown.......A method for hydrogen-loading air-silica optical fibres has been developed allowing out-diffusion times comparable to standard step-index fibres. Examples of the first grating written in Ge-doped air-silica fibres using a 266nm UV-laser are shown....

  14. Inferential Framework for Autonomous Cryogenic Loading Operations

    Science.gov (United States)

    Luchinsky, Dmitry G.; Khasin, Michael; Timucin, Dogan; Sass, Jared; Perotti, Jose; Brown, Barbara

    2017-01-01

    We address problem of autonomous cryogenic management of loading operations on the ground and in space. As a step towards solution of this problem we develop a probabilistic framework for inferring correlations parameters of two-fluid cryogenic flow. The simulation of two-phase cryogenic flow is performed using nearly-implicit scheme. A concise set of cryogenic correlations is introduced. The proposed approach is applied to an analysis of the cryogenic flow in experimental Propellant Loading System built at NASA KSC. An efficient simultaneous optimization of a large number of model parameters is demonstrated and a good agreement with the experimental data is obtained.

  15. Load and Global Response of Ships

    DEFF Research Database (Denmark)

    Jensen, Jørgen Juncher

    The present monograph covers wave load and global structural response for ships. It is primary written as a textbook for students with an introductionary background in naval architecture and a basic knowledge of statistics and strength of materials. The subjects are treated in details starting from...... first principles. The aim has been to derive and present the necessary theoretical framework for predicting the extreme loads and the corresponding hull girder stresses the ship may be subjected to during its operational lifetime.Although some account is given to reliabiity analysis, the present...

  16. Pressure Hull Analysis under Shock Loading

    Directory of Open Access Journals (Sweden)

    Ya-Jung Lee

    2008-01-01

    Full Text Available The hull of high performance submarines must resist underwater shock loading due to exploding torpedoes or depth bombs. An underwater shock involving an initial shock wave and successive bubble pulsating waves is so complex that a theoretical technique for deriving shock pressure distribution is required for improving simulation efficiency. Complete shock loading is obtained theoretically in this work, and responses of a submarine pressure hull are calculated using ABAQUS USA (Underwater Shock Analysis codes. In the long run, this deflection and stress data will assist in examining the structural arrangement of the submarine pressure hull.

  17. Stochastic Extreme Load Predictions for Marine Structures

    DEFF Research Database (Denmark)

    Jensen, Jørgen Juncher

    1999-01-01

    Development of rational design criteria for marine structures requires reliable estimates for the maximum wave-induced loads the structure may encounter during its operational lifetime. The paper discusses various methods for extreme value predictions taking into account the non-linearity of the ......Development of rational design criteria for marine structures requires reliable estimates for the maximum wave-induced loads the structure may encounter during its operational lifetime. The paper discusses various methods for extreme value predictions taking into account the non...

  18. Design of Vickers Hardness Loading Controller

    Directory of Open Access Journals (Sweden)

    Sihai Zhao

    2014-09-01

    Full Text Available Traditionally Vickers testing needs manual works, as a result, it will induce low precision and automatization. So this paper design a new type of loading controlling system, it is based on single chip computer 89S52, used PZT as the force generator in micro Vickers hardness testing. It primarily includes the designing of hardware, software of collecting data and PZT signals by AD667. This article has given the sketch of electrical circuit and controlling software, it also offers the experiment data. The experiments have showed that using this system can exactly control the loading results, and the average tolerance is less than 0.43 %.

  19. Intelligent electrical outlet for collective load control

    Science.gov (United States)

    Lentine, Anthony L.; Ford, Justin R.; Spires, Shannon V.; Goldsmith, Steven Y.

    2015-10-27

    Various technologies described herein pertain to an electrical outlet that autonomously manages loads in a microgrid. The electrical outlet can provide autonomous load control in response to variations in electrical power generation supply in the microgrid. The electrical outlet includes a receptacle, a sensor operably coupled to the receptacle, and an actuator configured to selectively actuate the receptacle. The sensor measures electrical parameters at the receptacle. Further, a processor autonomously controls the actuator based at least in part on the electrical parameters measured at the receptacle, electrical parameters from one or more disparate electrical outlets in the microgrid, and a supply of generated electric power in the microgrid at a given time.

  20. Pile Load Capacity – Calculation Methods

    Directory of Open Access Journals (Sweden)

    Wrana Bogumił

    2015-12-01

    Full Text Available The article is a review of the current problems of the foundation pile capacity calculations. The article considers the main principles of pile capacity calculations presented in Eurocode 7 and other methods with adequate explanations. Two main methods are presented: α – method used to calculate the short-term load capacity of piles in cohesive soils and β – method used to calculate the long-term load capacity of piles in both cohesive and cohesionless soils. Moreover, methods based on cone CPTu result are presented as well as the pile capacity problem based on static tests.

  1. Gust loading on streamlined bridge decks

    DEFF Research Database (Denmark)

    Larose, Guy; Mann, Jakob

    1998-01-01

    The current analytical description of the buffeting action of wind on long-span bridges is based on the strip assumption. However, recent experiments on closed-box girder bridge decks have shown that this assumption is not valid and is the source of an important part of the error margin...... of the analytical prediction methods. In this paper, an analytical model that departs from the strip assumption is used to describe the gust loading on a thin airfoil. A parallel is drawn between the analytical model and direct measurements of gust loading on motionless closed-box girder bridge decks. Empirical...

  2. Comparison of Deterministic and Probabilistic Radial Distribution Systems Load Flow

    Science.gov (United States)

    Gupta, Atma Ram; Kumar, Ashwani

    2017-08-01

    Distribution system network today is facing the challenge of meeting increased load demands from the industrial, commercial and residential sectors. The pattern of load is highly dependent on consumer behavior and temporal factors such as season of the year, day of the week or time of the day. For deterministic radial distribution load flow studies load is taken as constant. But, load varies continually with a high degree of uncertainty. So, there is a need to model probable realistic load. Monte-Carlo Simulation is used to model the probable realistic load by generating random values of active and reactive power load from the mean and standard deviation of the load and for solving a Deterministic Radial Load Flow with these values. The probabilistic solution is reconstructed from deterministic data obtained for each simulation. The main contribution of the work is: Finding impact of probable realistic ZIP load modeling on balanced radial distribution load flow. Finding impact of probable realistic ZIP load modeling on unbalanced radial distribution load flow. Compare the voltage profile and losses with probable realistic ZIP load modeling for balanced and unbalanced radial distribution load flow.

  3. Comparison of Deterministic and Probabilistic Radial Distribution Systems Load Flow

    Science.gov (United States)

    Gupta, Atma Ram; Kumar, Ashwani

    2017-12-01

    Distribution system network today is facing the challenge of meeting increased load demands from the industrial, commercial and residential sectors. The pattern of load is highly dependent on consumer behavior and temporal factors such as season of the year, day of the week or time of the day. For deterministic radial distribution load flow studies load is taken as constant. But, load varies continually with a high degree of uncertainty. So, there is a need to model probable realistic load. Monte-Carlo Simulation is used to model the probable realistic load by generating random values of active and reactive power load from the mean and standard deviation of the load and for solving a Deterministic Radial Load Flow with these values. The probabilistic solution is reconstructed from deterministic data obtained for each simulation. The main contribution of the work is: Finding impact of probable realistic ZIP load modeling on balanced radial distribution load flow. Finding impact of probable realistic ZIP load modeling on unbalanced radial distribution load flow. Compare the voltage profile and losses with probable realistic ZIP load modeling for balanced and unbalanced radial distribution load flow.

  4. 46 CFR 154.355 - Bow and stern loading piping.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Bow and stern loading piping. 154.355 Section 154.355... Arrangements § 154.355 Bow and stern loading piping. (a) Bow and stern loading piping must: (1) Meet § 154.310... other openings to accommodation, service, or control spaces that face the bow or stern loading area must...

  5. 14 CFR 23.393 - Loads parallel to hinge line.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Loads parallel to hinge line. 23.393... Control Surface and System Loads § 23.393 Loads parallel to hinge line. (a) Control surfaces and supporting hinge brackets must be designed to withstand inertial loads acting parallel to the hinge line. (b...

  6. 24 CFR 3285.315 - Special snow load conditions.

    Science.gov (United States)

    2010-04-01

    ... 24 Housing and Urban Development 5 2010-04-01 2010-04-01 false Special snow load conditions. 3285... Special snow load conditions. (a) General. Foundations for homes designed for and located in areas with roof live loads greater than 40 psf must be designed by the manufacturer for the special snow load...

  7. 14 CFR 23.371 - Gyroscopic and aerodynamic loads.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Gyroscopic and aerodynamic loads. 23.371... Flight Loads § 23.371 Gyroscopic and aerodynamic loads. (a) Each engine mount and its supporting structure must be designed for the gyroscopic, inertial, and aerodynamic loads that result, with the engine...

  8. Transient Monotonic and Cyclic Load Effects on Mono Bucket Foundations

    DEFF Research Database (Denmark)

    Nielsen, Søren Dam

    and when hitting the foundation they induce high impact loads with a short duration. It is important that the foundation is able to resists these huge loads. Fortunately, the conducted research showed that the capacity of the mono bucket foundation is high to impact loads. When exposed to a huge wave load...

  9. The inverse effects of load transfer and load sharing on axial compressive stiffness.

    Science.gov (United States)

    Haher, T R; Yeung, A W; Ottaviano, D M; Merola, A A; Caruso, S A

    2001-01-01

    The goal of spinal instrumentation is to stabilize involved motion segments while fusion occurs. Although some degree of load sharing is necessary for fusion, the ability of the instrumentation system to transfer the load may vary. The purpose of this study is to formulate a mathematical relationship between load sharing and load transfer of specific spinal instrumentation systems using a well-accepted mechanical model. Forty-eight American Society for Testing Materials standard ultra high molecular weight polyethylene cylinders were used as per designation F 1717-96, standard test methods for static and fatigue for spinal implant constructs in a corpectomy model. Twenty-four spinal assemblies consisting of anterior plates, anterior rod, and posterior rods were subjected to compression bending tests using a MTS Bionix servo-hydraulic material testing apparatus. Each implant was tested in compression bending with and without the addition of a titanium load-sharing cage. The force applied was the independent variable, and the displacement was the dependent variable. The stiffness was determined for each setup with and without the addition of an anterior load-sharing cage. The average axial compressive stiffness of a system increased by a factor of 8.5 with the addition of the load-sharing cage. An inverse relationship existed between the compressive stiffness of the construct and its relative increase achieved with the addition of the load-sharing cage. The compressive stiffness of the system with the addition of the load-sharing cage approached that of the anterior device itself as the system flexibility increased. The ability of instrumentation systems to load share or load transfer and their respective stiffness was determined. The 5-mm rod screw posterior system was compared with the 7-mm Ti posterior system with the addition of one and two devices for transverse traction (DTTs). The rods with the increased diameter had a stiffness of 1723 n/mm with one DTT and

  10. Allocation of Load-Loss Cost Caused by Voltage Sag

    Science.gov (United States)

    Gao, X.

    2017-10-01

    This paper focuses on the allocation of load-loss cost caused by voltage sag in the environment of electricity market. To compensate the loss of loads due to voltage sags, the load-loss cost is allocated to both sources and power consumers. On the basis of Load Drop Cost (LDC), a quantitative evaluation index of load-loss cost caused by voltage sag is identified. The load-loss cost to be allocated to power consumers themselves is calculated according to load classification. Based on the theory of power component the quantitative relation between sources and loads is established, thereby a quantitative calculation method for load-loss cost allocated to each source is deduced and the quantitative compensation from individual source to load is proposed. A simple five-bus system illustrates the main features of the proposed method.

  11. Outlier robustness for wind turbine extrapolated extreme loads

    DEFF Research Database (Denmark)

    Natarajan, Anand; Verelst, David Robert

    2012-01-01

    simulation is demonstrated and compared with published results. Further effects of varying wind inflow angles and shear exponent is brought out. Parametric fitting techniques that consider all extreme loads including ‘outliers’ are proposed, and the physical reasons that result in isolated high extreme loads...... dependencies is utilized to estimate a probability for the largest extreme load to occur at a specific mean wind speed. This inherently weights extreme loads that occur frequently within mean wind speed bins higher than isolated occurrences of extreme loads. Primarily, the results for the blade root out......-of-plane loads are presented here as those extrapolated loads have shown wide variability in literature, but the method can be generalized to any other component load. The convergence of the 1 year extrapolated extreme blade root out-of-plane load with the number of turbulent wind samples used in the loads...

  12. 46 CFR 78.50-15 - Load line marks.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 3 2010-10-01 2010-10-01 false Load line marks. 78.50-15 Section 78.50-15 Shipping... Vessels § 78.50-15 Load line marks. (a) Vessels assigned a load line shall have the deck line and the load line marks permanently scribed or embossed as required by subchapter E (Load Lines) of this chapter. (b) ...

  13. A grid-tied PV system for commercial load and peak load reduction: South African case study

    CSIR Research Space (South Africa)

    Senatla, Mamahloko

    2017-08-01

    Full Text Available in the analysis with the objective of reducing both the load demand and peak load for a South African commercial entity. The results show load and peak load reductions of 3.4% and 4.5 % respectively. This shows that if such or similar systems are adopted...

  14. Load Management in District Heating Operation

    DEFF Research Database (Denmark)

    Li, Hongwei; Wang, Stephen Jia

    2015-01-01

    Smooth operation of district heating system will avoid installation of expensive peak heat boilers, improve plant partial load performance, increase the system redundancy for further network expansion and improve its resilience to ensure security of supply during severe heating seasons. The peak...

  15. Work load and musculoskeletal complaints during pregnancy

    NARCIS (Netherlands)

    Paul, J. A.; van Dijk, F. J.; Frings-Dresen, M. H.

    1994-01-01

    Many pregnant women have musculoskeletal complaints, the onset and aggravation of which are thought to be associated with their activity or work postures. The purpose of this paper was to obtain more insight into the influence of pregnancy on the load of the musculoskeletal system at work to provide

  16. Preparation and Evaluation of Glibenclamide-Loaded ...

    African Journals Online (AJOL)

    The effect of stirring speed (250, 1000, 1500 and 2500 rpm) and drug: polymer ratio (1:1, 1: 2, 1:3 and 2:1) on particle size, size distribution, zeta potential, drug loading, encapsulation efficiency and drug release was also studied. Results: Stable NPs were successfully prepared without any incompatibility, as indicated by ...

  17. The chemistry induced by mechanical load

    CERN Document Server

    Frank, Irmgard

    2016-01-01

    Results in the field of mechanochemistry are summarized. For example under mechanical load often a solvolysis is observed instead of a simple homolytic bond rupture. Also a mechanically induced redox reaction was reported experimentally and could be modelled theoretically. With CPMD simulations it is possible to understand multi-step mechanisms in full detail.

  18. 14 CFR 23.443 - Gust loads.

    Science.gov (United States)

    2010-01-01

    ... Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Structure Vertical Surfaces § 23.443... specified in § 23.333(c)(2)(i). (c) In the absence of a more rational analysis, the gust load must be...

  19. 14 CFR 23.425 - Gust loads.

    Science.gov (United States)

    2010-01-01

    ... Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Structure Horizontal Stabilizing and...) In the absence of a more rational analysis, the incremental load due to the gust must be computed as...

  20. Load capacity of hollowed timber piles.

    Science.gov (United States)

    1998-12-01

    The goal of this study was to develop a reliable load-rating methodology for timber piles based on the level of documented damage. Louisiana currently has over 4,000 timber bridges in its inventory of over 13,800 bridges. A quarter of these 4,000 tim...

  1. Vocal Loading in Speaking a Foreign Language.

    Science.gov (United States)

    Järvinen, Kati; Laukkanen, Anne-Maria

    2015-01-01

    This study investigated whether speaking a foreign language affects the subjective notions of vocal fatigue, and whether acoustic measurements reveal a higher vocal loading. The speech samples of 20 native Finnish-speaking and 23 native English-speaking subjects were recorded in Finnish and in English. From the speech samples, fundamental frequency, equivalent sound level, total duration of voiced speech, speech rate, alpha ratio and L1-L0 level difference were analyzed. Vocal doses were calculated. According to subjective notions, the voice gets tired more quickly when speaking a foreign language. The mean fundamental frequency increased but the speech rate and total duration of voiced speech decreased significantly when speaking a foreign language. Thus, the vocal doses decreased. The subjective sensations of increased vocal fatigue may be due to increased mental stress rather than to higher vocal loading. However, a trend that speaking a foreign language may involve more loading was found in L1-L0 level difference and in the doses normalized to time dose. Longer speech samples should be studied. Voice quality-based indicators of vocal loading are worth testing in addition to the measures based on the amount of voicing in speech. © 2015 S. Karger AG, Basel.

  2. Maritime Load Dependent Lead Times - An Analysis

    DEFF Research Database (Denmark)

    Pahl, Julia; Voss, Stefan

    2017-01-01

    Traditionally, the maritime sector follows a very conservative approach towards sharing information and adopting information technology (IT) to stream-line logistic activities. Late arrivals of ships create problems especially with the trend to build large ships leading to peak loads of process...

  3. Critical Buckling Load on Large Spherical Shells

    DEFF Research Database (Denmark)

    Wedellsborg, B. W.

    1962-01-01

    Approximate evaluation for watertanks, hortonspheres, vapor containers, containment vessels for nuclear reactors, and so forth, has been computed, taking into account out-of-roundness and local flattened areas; graphs have been plotted giving critical buckling load as function of maximum radial...

  4. Stormwater contaminant loading following southern California wildfires.

    Science.gov (United States)

    Stein, Eric D; Brown, Jeffrey S; Hogue, Terri S; Burke, Megan P; Kinoshita, Alicia

    2012-11-01

    Contaminant loading associated with stormwater runoff from recently burned areas is poorly understood, despite the fact that it has the potential to affect downstream water quality. The goal of the present study is to assess regional patterns of runoff and contaminant loading from wildfires in urban fringe areas of southern California. Postfire stormwater runoff was sampled from five wildfires that each burned between 115 and 658 km(2) of natural open space between 2003 and 2009. Between two and five storm events were sampled per site over the first one to two years following the fires for basic constituents, metals, nutrients, total suspended solids, and polycyclic aromatic hydrocarbons (PAHs). Results were compared to data from 16 unburned natural areas and six developed sites. Mean copper, lead, and zinc flux (kg/km(2)) were between 112- and 736-fold higher from burned catchments and total phosphorus was up to 921-fold higher compared to unburned natural areas. Polycyclic aromatic hydrocarbon flux was four times greater from burned areas than from adjacent urban areas. Ash fallout on nearby unburned watersheds also resulted in a threefold increase in metals and PAHs. Attenuation of elevated concentration and flux values appears to be driven mainly by rainfall magnitude. Contaminant loading from burned landscapes has the potential to be a substantial contribution to the total annual load to downstream areas in the first several years following fires. Copyright © 2012 SETAC.

  5. Effects of Cognitive Load on Speech Recognition

    Science.gov (United States)

    Mattys, Sven L.; Wiget, Lukas

    2011-01-01

    The effect of cognitive load (CL) on speech recognition has received little attention despite the prevalence of CL in everyday life, e.g., dual-tasking. To assess the effect of CL on the interaction between lexically-mediated and acoustically-mediated processes, we measured the magnitude of the "Ganong effect" (i.e., lexical bias on phoneme…

  6. Liquid loading experiments with tube wall modifications

    NARCIS (Netherlands)

    Belfroid, S.P.C.; Schiferli, W.; Veltin, J.; Veeken, K.

    2011-01-01

    This paper discusses the multiphase flow mechanism responsible for gas-well liquid loading. It demonstrates that the conventional idea of droplet flow reversal (Turner et al. (1)) does not capture reality and that actual observations are better described by film flow reversal phenomenon. The

  7. A heavy load for heavy ions

    CERN Multimedia

    2003-01-01

    On 25 September, the two large coils for the dipole magnet of ALICE, the LHC experiment dedicated to heavy ions, arrived at Point 2 on two heavy load trucks after a 1200 km journey from their assembly in Vannes, France.

  8. Global Cryptosporidium Loads from Livestock Manure

    NARCIS (Netherlands)

    Vermeulen-Henstra, Lucie; Benders, Jorien; Medema, Gertjan; Hofstra, Nynke

    2017-01-01

    Understanding the environmental pathways of Cryptosporidium is essential for effective management of human and animal cryptosporidiosis. In this paper we aim to quantify livestock Cryptosporidium spp. loads to land on a global scale using spatially explicit process-based modeling, and to explore the

  9. Measuring Cognitive Load in Embodied Learning Settings

    Science.gov (United States)

    Skulmowski, Alexander; Rey, Günter Daniel

    2017-01-01

    In recent years, research on embodied cognition has inspired a number of studies on multimedia learning and instructional psychology. However, in contrast to traditional research on education and multimedia learning, studies on embodied learning (i.e., focusing on bodily action and perception in the context of education) in some cases pose new problems for the measurement of cognitive load. This review provides an overview over recent studies on embodied learning in which cognitive load was measured using surveys, behavioral data, or physiological measures. The different methods are assessed in terms of their success in finding differences of cognitive load in embodied learning scenarios. At the same time, we highlight the most important challenges for researchers aiming to include these measures into their study designs. The main issues we identified are: (1) Subjective measures must be appropriately phrased to be useful for embodied learning; (2) recent findings indicate potentials as well as problematic aspects of dual-task measures; (3) the use of physiological measures offers great potential, but may require mobile equipment in the context of embodied scenarios; (4) meta-cognitive measures can be useful extensions of cognitive load measurement for embodied learning. PMID:28824473

  10. Large Scale Demand Response of Thermostatic Loads

    DEFF Research Database (Denmark)

    Totu, Luminita Cristiana

    the temperature limits and other operational constraints, and by using only limited communication, it is possible to make use of the individual thermostat deadband flexibility to step-up or step-down the power consumption of the population as if it were a power plant. The individual thermostatic loads experience...

  11. Immediate implant loading: A case report

    OpenAIRE

    Dhamankar, Dilip; Gupta, Arun R.; Mahadevan, Janani

    2010-01-01

    Dental implants have long provided an excellent treatment option to restore edentulous spaces. Successful formation of a direct bone to implant interface is the goal in implant therapy. Immediate loading is an alternative to two stage surgical procedure. Improved surgical instrumentation implants design, and surface topography changes the concept of two stages surgical to one stage surgical procedure.

  12. Automatic Multimodal Cognitive Load Measurement (AMCLM)

    Science.gov (United States)

    2011-06-01

    activity is growing, measurement systems have yet to be prototyped. Future work will focus on prototypes that benefit the interaction between users and...Schmutz, P., Heinz, S., et al.,. 2009. Cognitive load in ecommerce applications: measurement and effects on user satisfaction. Adv. in Hum.-Comp

  13. Plastic collapse load of corroded steel plates

    Indian Academy of Sciences (India)

    Keywords. Corroded steel plate; plastic collapse; FEM; rough surface. ... The main aim of present work is to study plastic collapse load of corroded steel plates with irregular surfaces under tension. Non-linear finite element method ... Department of Ocean Engineering, AmirKabir University of Technology, 15914 Tehran, Iran ...

  14. Curable off-loading footwear and methods

    DEFF Research Database (Denmark)

    2007-01-01

    Custom footbed devices, methods of constructing the devices and kits for constructing custom footbeds are disclosed that may be particularly advantageous in the treatment of plantar ulcers. The devices offer the advantage of off-loading pressure from the plantar ulcers in a device that is easy to...

  15. Interior moisture design loads for residences

    Science.gov (United States)

    Anton TenWolde; Iain S. Walker

    2001-01-01

    This paper outlines a methodology to obtain design values for indoor boundary conditions for moisture design calculations for residences. This is part of a larger effort by ASHRAE Standard Project Committee 160P, Design Criteria for Moisture Control in Buildings, to formulate criteria for moisture design loads, analysis techniques, and material and building performance...

  16. Measuring Cognitive Load in Embodied Learning Settings

    Directory of Open Access Journals (Sweden)

    Alexander Skulmowski

    2017-08-01

    Full Text Available In recent years, research on embodied cognition has inspired a number of studies on multimedia learning and instructional psychology. However, in contrast to traditional research on education and multimedia learning, studies on embodied learning (i.e., focusing on bodily action and perception in the context of education in some cases pose new problems for the measurement of cognitive load. This review provides an overview over recent studies on embodied learning in which cognitive load was measured using surveys, behavioral data, or physiological measures. The different methods are assessed in terms of their success in finding differences of cognitive load in embodied learning scenarios. At the same time, we highlight the most important challenges for researchers aiming to include these measures into their study designs. The main issues we identified are: (1 Subjective measures must be appropriately phrased to be useful for embodied learning; (2 recent findings indicate potentials as well as problematic aspects of dual-task measures; (3 the use of physiological measures offers great potential, but may require mobile equipment in the context of embodied scenarios; (4 meta-cognitive measures can be useful extensions of cognitive load measurement for embodied learning.

  17. CDMA coverage under mobile heterogeneous network load

    NARCIS (Netherlands)

    Saban, D.; van den Berg, Hans Leo; Boucherie, Richardus J.; Endrayanto, A.I.

    2002-01-01

    We analytically investigate coverage (determined by the uplink) under non-homogeneous and moving traffic load of third generation UMTS mobile networks. In particular, for different call assignment policies, we investigate cell breathing and the movement of the coverage gap occurring between cells

  18. ANTHROPOGENIC LOAD ON RIVERS OF URBAN AREAS

    Directory of Open Access Journals (Sweden)

    Kurochkina Valentina Aleksandrovna

    2016-08-01

    Full Text Available The increasing speed of urbanization and population growth lead to the increasing anthropogenic load on water bodies. The urbanization processes in Russia are more intensive than in other countries. The dense population and great industrial potential lead to the fact that the urbanized territories become the main sources of water pollution. That’s why the environmental control of the state of water objects is needed. In the article the authors study the problem of anthropogenic load impact on river hydraulics processes and on the properties of river sediments that determine river channels evolution and general ecological state of water bodies. The interrelation between ecological state of water bodies, the quality of water in it and the level of contamination with sediments was determined. It is established that the conditions of long-term aquatic life as a whole and of water quality in particular depend on the contamination level with sediments. The author proposes a method of estimation of anthropogenic load on rivers. The paper analyses the calculation results of the value of anthropogenic load on different rivers of Russia.

  19. Direct Load Control by AC Frequency Modulation

    DEFF Research Database (Denmark)

    Douglass, Philip James; You, Shi

    2012-01-01

    from this technology because their low inertia. The paper proposes a operating procedure for utilizing DFCR loads for energy balancing, expanding DFCR’s well known role as a power balancing resource. The system operator can use DFCR for energy balancing by adjusting the frequency controller...

  20. Load Response Analysis of Asphalt Pavement

    Directory of Open Access Journals (Sweden)

    Xiao Zhijun

    2016-01-01

    Full Text Available Based on the filed data of Fuzhou test road, load response regulation of nonlinear pavement structure was analyzed in this paper; Mechanics software was adopted to analyze linear elastic and nonlinear of the pavement structure, analyzed results and road filed data were compared, and determine the correlation between them and the field data.

  1. Loads of Sewer Manholes within Mining Area

    Directory of Open Access Journals (Sweden)

    Magdalena Zięba

    2014-01-01

    Originality/Value: The presented method is an original concept. It enables the determination of additional external horizontal loads acting on sewer manholes within mining areas, in particular the flexible manholes made of thermoplastics. It also enables the determination of dependencies of changes in the cross-sections of risers of flexible sewer manholes (with different circumferential stiffness on the horizontal soil strains.

  2. Fatigue Reliability under Multiple-Amplitude Loads

    DEFF Research Database (Denmark)

    Talreja, R.

    1979-01-01

    A method to determine the fatigue of structures subjected to multiple-amplitude loads is presented. Unlike the more common cumulative damage methods, which are usually based on fatigue life data, the proposed method is based on tensile strength data. Assuming the Weibull distribution for the init...

  3. Monopod Bucket Foundations Under Cyclic Lateral Loading

    DEFF Research Database (Denmark)

    Foglia, Aligi; Ibsen, Lars Bo

    2016-01-01

    The monopod bucket foundation has the potential to become a cost-reducing substructure for offshore wind turbines. To avoid problems during the energy converter operation, the long-term effect of cyclic loading must be considered in the design of the foundation. In this paper, a 1-g testing rig...

  4. Monopod bucket foundations under cyclic lateral loading

    DEFF Research Database (Denmark)

    Foglia, Aligi; Ibsen, Lars Bo

    The monopod bucket foundation can be a cost-reducing sub-structure for offshore wind turbines. To avoid problems during the turbine operation, the long-term effect of cyclic loading must be considered in the design of the foundation. In this paper a 1g testing rig is adopted to extend the knowledge...

  5. Material properties under intensive dynamic loading

    CERN Document Server

    Cherne, Frank J; Zhernokletov, Mikhail V; Glushak, B L; Zocher, Marvin A

    2007-01-01

    Understanding the physical and thermomechanical response of materials subjected to intensive dynamic loading is a challenge of great significance in engineering today. This volume assumes the task of gathering both experimental and diagnostic methods in one place, since not much information has been previously disseminated in the scientific literature.

  6. Characterization Of Glipizide-Loaded Polymethacrylate ...

    African Journals Online (AJOL)

    glipizide in the drug-loaded microspheres. Scanning electron microscopy revealed that the microspheres were spherical in nature. From the in vitro drug dissolution studies it was found that the sustaining effect of microspheres depended on the polymer concentration, amount of dispersant used and the type of polymer used ...

  7. Lake Erie phosphorus loading and Cladophora updates

    Science.gov (United States)

    The presentation will focus on updates or progress being made on each Phosphorus Loadings and Cladophora for Lake Erie. The format will give a brief summary of data, findings, and results that were used by the Great Lakes Water Quality Agreement (GLWQA) Annex 4 Nutrients Modeli...

  8. Robust control investigations for equipment loaded panels

    DEFF Research Database (Denmark)

    Aglietti, G.S.; Langley, R.S.; Rogers, E.

    1998-01-01

    This paper develops a modelling technique for equipment load panels which directly produces (adequate) models of the underlying dynamics on which to base robust controller design/evaluations. This technique is based on the use of the Lagrange's equations of motion and the resulting models...

  9. RPL LOAD BALANCING IN INTERNET OF THINGS

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Parsaei

    2017-12-01

    Full Text Available ABSTRACT:  The wide address space provided by Internet Protocol version 6 (IPv6 lets any thing to be identified uniquely. consistency of the modified version of IPv6 protocol stack with smart objects, facilitated the Internet interconnection of the networks of smart objects and introduced Internet of things. A smart object is a small micro-electronic device that consists of a communication device, a small microprocessor and a sensor or an actuator. A network made of such devices is called low-power and lossy network. RPL routing protocol that is consistent to IPv6, is designed to be used in these kinds of networks. Load balancing is not considered in the RPL design process. Whenever RPL is used in large scale low-power and lossy networks some nodes will suffer from congestion and this problem severely degrades network performance. In this paper, we consider solutions provided to tackle RPL load balancing problems. Load balancing algorithms and protoclos are evaluated through simulation. We evaluate IETF RPL implementation and LB-RPL method with Contiki OS Java (COOJA simulator. They are assessed comprehensively through metrics such as Packet delivery Ratio, Average End to End delay, and Gateway Throughput. LB-RPL improves RPL in terms of Packet delivery Ratio and throughput but increases Average End to End delay. Simulations results show that RPL load balancing needs extensive works to be performed yet.

  10. Cervical human spine loads during traumatomechanical investigations

    NARCIS (Netherlands)

    Kallieris, D.; Rizzetti, A.; Mattern. R.; Thunnissen, J.G.M.; Philippens, M.M.G.M.

    1996-01-01

    The last decade's improvements in automotive safety resulted into a significant decrease of fatal injuries. However, due to the use of belts and airbags it can be observed that cervical spine injuries, non-severe and severe, have become more important. It seems that inertial loading of the neck by

  11. Bayesian techniques for surface fuel loading estimation

    Science.gov (United States)

    Kathy Gray; Robert Keane; Ryan Karpisz; Alyssa Pedersen; Rick Brown; Taylor Russell

    2016-01-01

    A study by Keane and Gray (2013) compared three sampling techniques for estimating surface fine woody fuels. Known amounts of fine woody fuel were distributed on a parking lot, and researchers estimated the loadings using different sampling techniques. An important result was that precise estimates of biomass required intensive sampling for both the planar intercept...

  12. Interactive Distance Education: A Cognitive Load Perspective

    Science.gov (United States)

    Kalyuga, Slava

    2012-01-01

    Evidence-based approaches to the design of the next generation of interactive distance education need to take into account established multimedia learning principles. Cognitive load theory is a theory that has significantly contributed to the development of such principles. It has applied our knowledge of major features and processing limitations…

  13. Technical note: Spine loading in automotive seating

    NARCIS (Netherlands)

    Zenk, R.; Franz, M.; Bubb, H.; Vink, P.

    2012-01-01

    For car manufacturers, seat comfort is becoming more important in distinguishing themselves from their competitors. Therefore, many studies on participative seat comfort are carried out. In this paper, an objective assessment approach is reported which evaluates the concept of "optimal load

  14. Preparation of embolic NEMs loading capecitabine.

    Science.gov (United States)

    Liu, Yuangang; He, Peng; Wang, Shibin; Sun, Xuezhan; Chen, Aizheng

    2013-01-01

    The nanoparticles-embedded microcapsules (NEMs) with smooth surface, good sphericity, excellent dispersivity and uniform particle size distribution were prepared by emulsification combined with electrospraying to extend the sustained release performance of the embolic microcapsules loading capecitabine (CAP). The sodium alginate and chitosan with good biocompatibility were used as the materials and CAP as a small-molecule model drug. The drug loading, encapsulation efficiency and drug release of CAP in the NEMs were investigated. The results showed that the drug-loading and encapsulation efficiency both increased with the increment of chitosan and CAP concentration. The maximum values of drug loading and encapsulation efficiency were 1.97 and 18.01 % respectively when initial CAP concentration was 5.0 g/L and chitosan molecular weight 100 kDa. The cumulative release rate of CAP released from the NEMs was lower than 30 % in 0.5 h, which indicated that there was no obvious initial burst release behavior. In the subsequent 240 h, the release results confirmed that the NEMs had better sustained release properties compared to pure microcapsules, and it might be a new anticancer drug delivery system in the future studies.

  15. Residual load carrying capacity of timber joints

    NARCIS (Netherlands)

    Kuilen, J.W.G. van de

    1999-01-01

    Timber joints that have been preloaded for 2 to 8 years have been short term tested in accordance with EN 26891. The applied load levels varied between 30% and 50% of the average short term strength. The study comprised nailed, toothed-plate and split-ring joints. All joints were made of spruce and

  16. Dust Load on Surfaces in Animal Buildings

    DEFF Research Database (Denmark)

    Lengweiler, P.; Strøm, J. S.; Takai, H.

    To investigate the physical process of particle deposition on and resuspension from surfaces in animal buildings, a test facility and a sampling method is established. The influences of surface orientation and air turbulence and velocity just as other parameters on the dust load on a surface...

  17. A closer look at salt loaded microstructures

    NARCIS (Netherlands)

    Rooij, M.R. de

    2006-01-01

    Many walls of ancient buildings are covered with plaster layers. Amongst the most recurrent causes of damage of plasters and substrates are moisture and salt decay processes. To combat these salt problems, special salt resistant plasters have been developed for application on salt loaded substrates.

  18. The critical shear load of rectangular plates

    Science.gov (United States)

    Seydel, Edgar

    1933-01-01

    This report gives formulas for analyzing the critical shear load of a simply supported square, isotropic (simple flat plate), or orthogonal anisotropic plate (a plate in which the rigidity in two directions perpendicular to each other is different, i.e. plywood or corrugated sheet), these formulas, although arrived at by approximation method, seem to agree fairly well with experimental results.

  19. A complete algorithm for fixture loading

    Energy Technology Data Exchange (ETDEWEB)

    Yu, K. [Duksung Women`s Univ., Seoul (Korea, Republic of). Dept. of Computer Science; Goldberg, K.Y. [Univ. of California, Berkeley, CA (United States). Industrial Engineering and Operations Research

    1998-11-01

    A fixture is a device for locating and holding parts. Since the initial position and orientation of a part may be uncertain, the act of loading the part into the fixture must compensate for this uncertainty. Machinists often refer to the 3-2-1 rule: place the part onto 3-point contact with a horizontal support plane, slide the part along this plane into 2-point contact with the fixture, then translate along this edge until a 1-point contact uniquely locates the part. This rule of thumb implicitly assumes both sensing and compliance: applied forces change as contacts are detected. In this paper, the authors geometrically formalize robotic fixture loading as a sensor-based compliant assembly problem and give a complete planning algorithm. They consider the class of modular fixtures that use three locators and one clamp (Brost and Goldberg 1996), and discuss a class of robot commands that cause the part to slide and rotate in the support plane. Sensing is achieved with binary contact sensors on each locator; compliance is achieved with a passive spring-loaded mechanism at the robot and effector. The authors extend the theory of sensor-based compliant motion planning to generalized polygonal C-spaces, and give a complete planning algorithm: it is guaranteed to find a loading plan when one exists and to return a negative report otherwise. The authors report on experiments using the resulting plans. Finally, they use this formalization to prove a sufficient condition for the 3-2-1 rule.

  20. Structural Loads Analysis for Wave Energy Converters

    Energy Technology Data Exchange (ETDEWEB)

    van Rij, Jennifer A [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Yu, Yi-Hsiang [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Guo, Yi [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-06-03

    This study explores and verifies the generalized body-modes method for evaluating the structural loads on a wave energy converter (WEC). Historically, WEC design methodologies have focused primarily on accurately evaluating hydrodynamic loads, while methodologies for evaluating structural loads have yet to be fully considered and incorporated into the WEC design process. As wave energy technologies continue to advance, however, it has become increasingly evident that an accurate evaluation of the structural loads will enable an optimized structural design, as well as the potential utilization of composites and flexible materials, and hence reduce WEC costs. Although there are many computational fluid dynamics, structural analyses and fluid-structure-interaction (FSI) codes available, the application of these codes is typically too computationally intensive to be practical in the early stages of the WEC design process. The generalized body-modes method, however, is a reduced order, linearized, frequency-domain FSI approach, performed in conjunction with the linear hydrodynamic analysis, with computation times that could realistically be incorporated into the WEC design process.

  1. Electricity load modelling using computational intelligence

    NARCIS (Netherlands)

    Ter Borg, R.W.

    2005-01-01

    As a consequence of the liberalisation of the electricity markets in Europe, market players have to continuously adapt their future supply to match their customers' demands. This poses the challenge of obtaining a predictive model that accurately describes electricity loads, current in this thesis.

  2. Low-Load Space Conditioning Needs Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Puttagunta, Srikanth [Consortium for Advanced Residential Buildings (CARB), Norwalk, CT (United States)

    2015-05-19

    Heating, ventilating, and air-conditioning (HVAC) equipment must be right-sized to ensure energy performance and comfort. With limited low-load options in the HVAC market, many new-construction housing units are being fitted with oversized equipment that creates system efficiency, comfort, and cost penalties. To bridge the gap between currently available HVAC equipment that is oversized or inefficient and the rising demand for low-load HVAC equipment in the marketplace, HVAC equipment manufacturers need to be fully aware of the needs of the multifamily building and attached single-family (duplex and townhouse) home market. Over the past decade, Steven Winter Associates, Inc. (SWA) has provided certification and consulting services for hundreds of housing projects and has accrued a large pool of data that describe multifamily and attached single-family home characteristics. The U.S. Department of Energy’s Building America research team Consortium for Advanced Residential Buildings (CARB) compiled and analyzed these data to outline the characteristics of low-load dwellings such as the heating and cooling design loads.

  3. Wind loads on solar energy roofs

    NARCIS (Netherlands)

    Geurts, C.P.W.; Bentum, C.A. van

    2007-01-01

    This paper presents an overview of the wind loads on roofs, equipped with solar energy products, so called Active Roofs. Values given in this paper have been based on wind tunnel and full scale measurements, carried out at TNO, and on an interpretation of existing rules and guidelines. The results

  4. Lower limb loading in step aerobic dance.

    Science.gov (United States)

    Wu, H-W; Hsieh, H-M; Chang, Y-W; Wang, L-H

    2012-11-01

    Participation in aerobic dance is associated with a number of lower extremity injuries, and abnormal joint loading seems to be a factor in these. However, information on joint loading is limited. The purpose of this study was to investigate the kinetics of the lower extremity in step aerobic dance and to compare the differences of high-impact and low-impact step aerobic dance in 4 aerobic movements (mambo, kick, L step and leg curl). 18 subjects were recruited for this study. High-impact aerobic dance requires a significantly greater range of motion, joint force and joint moment than low-impact step aerobic dance. The peak joint forces and moments in high-impact step aerobic dance were found to be 1.4 times higher than in low-impact step aerobic dance. Understanding the nature of joint loading may help choreographers develop dance combinations that are less injury-prone. Furthermore, increased knowledge about joint loading may be helpful in lowering the risk of injuries in aerobic dance instructors and students. © Georg Thieme Verlag KG Stuttgart · New York.

  5. Wave Load Prediction - a Design Tool

    DEFF Research Database (Denmark)

    Pedersen, Tommy

    of available theoretical methods for determining wave loads on a ship, three have been selected. The criteria areRobustness of the method in as wide a range of applications as possible.Reasonable computational time on a state-of-the art PC.Accuracy within engineering practive.Linear as well as non-linear...... predictions should be available....

  6. 1999 Pacific Northwest Loads and Resources Study.

    Energy Technology Data Exchange (ETDEWEB)

    United States. Bonneville Power Administration.

    1999-12-01

    The Pacific Northwest Loads and Resources Study (White Book) is published annually by BPA and establishes the planning basis for supplying electricity to customers. It serves a dual purpose. First, the White Book presents projections of regional and Federal system load and resource capabilities, along with relevant definitions and explanations. Second, the White Book serves as a benchmark for annual BPA determinations made pursuant to its regional power sales contracts. Specifically, BPA uses the information in the White Book for determining the notice required when customers request to increase or decrease the amount of power purchased from BPA. The White Book will not be used in calculations for the 2002 regional power sales contract subscription process. The White Book compiles information obtained from several formalized resource planning reports and data submittals, including those from the Northwest Power Planning Council (Council) and the Pacific Northwest Utilities Conference Committee (PNUCC). The White Book is not an operational planning guide, nor is it used for determining BPA revenues. Operation of the Federal Columbia River Power System (FCRPS) is based on a set of criteria different from that used for resource planning decisions. Operational planning is dependent upon real-time or near-term knowledge of system conditions, including expectations of river flows and runoff, market opportunities, availability of reservoir storage, energy exchanges, and other factors affecting the dynamics of operating a power system. In this loads and resources study, resource availability is compared with a medium forecast of electricity consumption. The forecasted future electricity demands--firm loads--are subtracted from the projected capability of existing and ''contracted for'' resources to determine whether BPA and the region will be surplus or deficit. If Federal system resources are greater than loads in any particular year or month, there is

  7. Mechanisms to absorb load in amputee running.

    Science.gov (United States)

    Strike, Siobhan C; Wickett, Oliver; Schoeman, Marlene; Diss, Ceri E

    2012-09-01

    We aimed to determine if a shock absorbing pylon (SAP) influenced the ground reaction force characteristics and the shock absorbing mechanisms compared to a rigid pylon (Rigid) during the loading phase in running. To determine if the SAP influences the mechanisms of loading compared to the Rigid condition. A convenience sample of transtibial amputees participated in a laboratory-based study. The prosthetic set-up was randomly altered fd\\sdsd. Five recreationally active male transtibial amputees age: 18-50 years; mean mass: 86.7 ± 17.5 kg; height: 1.77 ± 0.07 m) volunteered from a population-based sample. They completed a within-participant-designed study assessing a SAP and a Rigid condition during running. Kinematic and kinetic data were collected during two sessions following a one-week customization period. Loading rate, peak vertical and horizontal ground reaction forces and the time to each measure along with knee and hip angular displacement, absorbing powers and work done between the SAP and Rigid conditions were not systematically affected by the prosthetic condition. The effect of the SAP was minimal and inconsistent in the loading phase, with only some amputees presenting higher and others with lower values for the tested variables.

  8. Shaft Center Orbit in Dynamically Loaded Bearings

    DEFF Research Database (Denmark)

    Klit, Peder

    2005-01-01

    The aim of this work is to demonstrate how to utilize the bearings damping coe±cients to estimate the orbit for a dynamically loaded journal bearing. The classical method for this analysis was developed by Booker in 1965 [1]and described further in 1972 [2]. Several authors have re¯ned this metho...

  9. Complex Regression Functional And Load Tests Development

    Directory of Open Access Journals (Sweden)

    Anton Andreevich Krasnopevtsev

    2015-10-01

    Full Text Available The article describes practical approaches for realization of automatized regression functional and load testing on random software-hardware complex, based on «MARSh 3.0» sample. Testing automatization is being realized for «MARSh 3.0» information security increase.

  10. Three-Dimensional Dynamic Loading of Sand

    Science.gov (United States)

    2011-02-01

    Proceedings of the DYMAT 2009, EDP Sciences, 201–205, 2009, Brussels Belgium [xix] Bragov, AM, Kotov, VL, Lomunov, AK, and Sergeichev, IV...Conferences on the Mechanical and Physical Behaviour of Materials under Dynamic Loading, vol. , 2009, pp. , 1545-1552, published by EDP Sciences (www.dymat

  11. Static ice loads on hydro-electric structures: ice loads monographs: Volume 2: Appendices

    Energy Technology Data Exchange (ETDEWEB)

    Comfort, G.; Abdelnour, R.; Gong, Y.; Dinovitzer, A.

    1996-07-01

    Ice loads on hydro-electric structures were measured during a four-year field program. Loads were measured at Hydro-Quebec`s Paugan dam, Ontario Hydro`s Arnprior and Otto Holden dams, and in a large outdoor basin at the National Research Council (NRC) during one winter. The overall objective was to improve techniques for predicting ice loads on hydro-electric structures and the factors controlling them. The final report on the project was submitted as volume 1 of this two-volume work. This second volume contains the following appendices: (1) the stress distribution analyses for the Arnprior and Otto Holden dam sites, (2) the finite element model for the Arnprior and Otto Holden dams and reservoirs, (3) a numerical model of the loads produced by water level changes, (4) a model used to investigate the load distribution between the Paugan dam`s gates and piers, (5) a comparison between the measured loads and those given by the available ice load predictors, (6) ice cracking patterns at the dams, and (7) a listing of monitoring sites and sensor layouts use in this study. tabs., figs.

  12. The reliability of the Extra Load Index as a measure of relative load carriage economy.

    Science.gov (United States)

    Hudson, Sean; Cooke, Carlton; Lloyd, Ray

    2017-09-01

    The aim of this study was to measure the reliability of the extra load index (ELI) as a method for assessing relative load carriage economy. Seventeen volunteers (12 males, 5 females) performed walking trials at 3 km·h-1, 6 km·h-1 and a self-selected speed. Trial conditions were repeated 7 days later to assess test-retest reliability. Trials involved four 4-minute periods of walking, each separated by 5 min of rest. The initial stage was performed unloaded followed in a randomised order by a second unloaded period and walking with backpacks of 7 and 20 kg. Results show ELI values did not differ significantly between trials for any of the speeds (p = 0.46) with either of the additional loads (p = 0.297). The systematic bias, limits of agreement and coefficients of variation were small in all trial conditions. We conclude the ELI appears to be a reliable measure of relative load carriage economy. Practitioner Summary: This paper demonstrates that the ELI is a reliable measure of load carriage economy at a range of walking speeds with both a light and heavy load. The ELI, therefore, represents a useful tool for comparing the relative economy associated with different load carriage systems.

  13. Direct contribution of axial impact compressive load to anterior tibial load during simulated ski landing impact.

    Science.gov (United States)

    Yeow, C H; Lee, P V S; Goh, J C H

    2010-01-19

    Anterior tibial loading is a major factor involved in the anterior cruciate ligament (ACL) injury mechanism during ski impact landing. We sought to investigate the direct contribution of axial impact compressive load to anterior tibial load during simulated ski landing impact of intact knee joints without quadriceps activation. Twelve porcine knee specimens were procured. Four specimens were used as non-impact control while the remaining eight were mounted onto a material-testing system at 70 degrees flexion and subjected to simulated landing impact, which was successively repeated with incremental actuator displacement. Four specimens from the impacted group underwent pre-impact MRI for tibial plateau angle measurements while the other four were subjected to histology and microCT for cartilage morphology and volume assessment. The tibial plateau angles ranged from 29.4 to 38.8 degrees . There was a moderate linear relationship (Y=0.16X; R(2)=0.64; p<0.001) between peak axial impact compressive load (Y) and peak anterior tibial load (X). The anterior and posterior regions in the impacted group sustained surface cartilage fraying, superficial clefts and tidemark disruption, compared to the control group. MicroCT scans displayed visible cartilage deformation for both anterior and posterior regions in the impacted group. Due to the tibial plateau angle, increased axial impact compressive load can directly elevate anterior tibial load and hence contribute to ACL failure during simulated landing impact. Axial impact compressive load resulted in shear cartilage damage along anterior-posterior tibial plateau regions, due to its contribution to anterior tibial loading. This mechanism plays an important role in elevating ACL stress and cartilage deformation during impact landing. Copyright 2009 Elsevier Ltd. All rights reserved.

  14. Load alleviation potential of active flaps and individual pitch control in a full design load basis

    DEFF Research Database (Denmark)

    Barlas, Athanasios; Bergami, Leonardo; Hansen, Morten Hartvig

    2015-01-01

    configuration is evaluated by comparing four setups: 1) baseline with collective pitch, 2) individual pitch control, 3) individual flap control and 4) individual flap control combined with individual pitch control. The CRTEF allows for a significant reduction of the lifetime fatigue on various load channels......The load alleviation potential of the Controllable Rubber Trailing Edge Flap (CRTEF) is verified on a full Design Load Basis (DLB) setup using the aeroelastic code HAWC2, and by investigating a flap configuration for the NREL 5MW Reference Wind Turbine (RWT) model. The performance of the CRTEF...

  15. Differences in lumbar spine load due to posture and upper limb external load.

    Science.gov (United States)

    Kamińska, Joanna; Roman-Liu, Danuta; Zagrajek, Tomasz; Borkowski, Paweł

    2010-01-01

    As the lumbar region of the spine is particularly predisposed to musculoskeletal disorders, the aim of this article was to assess lumbar spine load on the basis of an accurate model of this part of the body. The model was developed with the finite element method and the energy criterion for optimising muscle work. Computer calculations confirmed that stresses and compression forces in intervertebral discs increased with an increase in the load force and that they were significantly larger in the bent forwards posture than in the erect posture. This result clearly shows that lifting light objects and the erect posture are important elements in minimising spine load.

  16. Thermal conductivity of evacuated perlite at low temperatures as a function of load and load history

    Science.gov (United States)

    Dube, W. P.; Sparks, L. L.; Slifka, A. J.

    1991-01-01

    Perlite, a powdered insulation, is commonly used in large cryogenic storage dewars. When these dewars are thermally cycled, the perlite in the evacuated space between the inner and outer vessels of the dewar experiences a changing mechanical load due to thermal expansion and contraction of the inner vessel. Thermal conductivity data were obtained using a boil-off calorimeter. The apparent thermal conductivity of evacuated perlite increases strongly with applied load. Hysteretic behavior of the conductivity was observed when perlite was subjected to cyclic mechanical loading.

  17. Reduced design load basis for ultimate blade loads estimation in multidisciplinary design optimization frameworks

    DEFF Research Database (Denmark)

    Pavese, Christian; Tibaldi, Carlo; Larsen, Torben J.

    2016-01-01

    The aim is to provide a fast and reliable approach to estimate ultimate blade loads for a multidisciplinary design optimization (MDO) framework. For blade design purposes, the standards require a large amount of computationally expensive simulations, which cannot be efficiently run each cost...... function evaluation of an MDO process. This work describes a method that allows integrating the calculation of the blade load envelopes inside an MDO loop. Ultimate blade load envelopes are calculated for a baseline design and a design obtained after an iteration of an MDO. These envelopes are computed...

  18. Evaluation of Load Rejection to house load test at 50% power for UCN 3

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Chang Gyun; Sohn, Suk Whun; Sohn, Jong Joo; Seo, Jong Tae; Lee, Sang Keun [Korea Power Engineering Company, Inc., Seoul (Korea, Republic of); Kim, Yong Sung; Nam, Kyu Won; Jung, Yang Mook; Chae, Kyeong Sik; Koh, Bum Jae; Oh, Chul Sung; Park, Hee Chool [Korea Electric Power Corporation, Taejon (Korea, Republic of)

    1998-12-31

    The Load Rejection to House Load test at 50% power was successfully performed during the UCN 3 PAT period. In this test, all plant control systems automatically controlled the plant from 50% power to house load operation mode. The KISPAC code, which was used in the performance analysis during the design process of UCN 3 and 4, predictions of the test agreed with the measured data demonstrating the validity of the code as well as the completeness of the plant design. 3 refs., 8 figs., 1 tab. (Author)

  19. HIV DNA-Adenovirus Multiclade Envelope Vaccine Induces gp41 Antibody Immunodominance in Rhesus Macaques.

    Science.gov (United States)

    Han, Qifeng; Williams, Wilton B; Saunders, Kevin O; Seaton, Kelly E; Wiehe, Kevin J; Vandergrift, Nathan; Von Holle, Tarra A; Trama, Ashley M; Parks, Robert J; Luo, Kan; Gurley, Thaddeus C; Kepler, Thomas B; Marshall, Dawn J; Montefiori, David C; Sutherland, Laura L; Alam, Munir S; Whitesides, John F; Bowman, Cindy M; Permar, Sallie R; Graham, Barney S; Mascola, John R; Seed, Patrick C; Van Rompay, Koen K A; Tomaras, Georgia D; Moody, M Anthony; Haynes, Barton F

    2017-11-01

    Dominant antibody responses in vaccinees who received the HIV-1 multiclade (A, B, and C) envelope (Env) DNA/recombinant adenovirus virus type 5 (rAd5) vaccine studied in HIV-1 Vaccine Trials Network (HVTN) efficacy trial 505 (HVTN 505) targeted Env gp41 and cross-reacted with microbial antigens. In this study, we asked if the DNA/rAd5 vaccine induced a similar antibody response in rhesus macaques (RMs), which are commonly used as an animal model for human HIV-1 infections and for testing candidate HIV-1 vaccines. We also asked if gp41 immunodominance could be avoided by immunization of neonatal RMs during the early stages of microbial colonization. We found that the DNA/rAd5 vaccine elicited a higher frequency of gp41-reactive memory B cells than gp120-memory B cells in adult and neonatal RMs. Analysis of the vaccine-induced Env-reactive B cell repertoire revealed that the majority of HIV-1 Env-reactive antibodies in both adult and neonatal RMs were targeted to gp41. Interestingly, a subset of gp41-reactive antibodies isolated from RMs cross-reacted with host antigens, including autologous intestinal microbiota. Thus, gp41-containing DNA/rAd5 vaccine induced dominant gp41-microbiota cross-reactive antibodies derived from blood memory B cells in RMs as observed in the HVTN 505 vaccine efficacy trial. These data demonstrated that RMs can be used to investigate gp41 immunodominance in candidate HIV-1 vaccines. Moreover, colonization of neonatal RMs occurred within the first week of life, and immunization of neonatal RMs during this time also induced a dominant gp41-reactive antibody response.IMPORTANCE Our results are critical to current work in the HIV-1 vaccine field evaluating the phenomenon of gp41 immunodominance induced by HIV-1 Env gp140 in RMs and humans. Our data demonstrate that RMs are an appropriate animal model to study this phenomenon and to determine the immunogenicity in new HIV-1 Env trimer vaccine designs. The demonstration of gp41 immunodominance in memory B cells of both adult and neonatal RMs indicated that early vaccination could not overcome gp41 dominant responses. Copyright © 2017 American Society for Microbiology.

  20. Load rating and retrofit testing of bridge timber piles subjected to eccentric loading.

    Science.gov (United States)

    2012-11-01

    This report first evaluated the load rating procedure currently in use by the Illinois Department of Transportation (IDOT) for rating timber : piles supporting multiple-span, simply supported bridges. For simplicity, these piles are often rated under...

  1. METHOD OF LOADING OF SURFACES OF INFLUENCE BY TEMPORARY MOVING LOAD LM1

    Directory of Open Access Journals (Sweden)

    Ilyushin Nikolay Viktorovich

    2012-10-01

    The proposed methodology represents an unambiguous solution to the problem of identification of unfavourable positions of the temporary moving load LM1 (EN 1991-2 and the extreme forces or relocations involved in this respect.

  2. ANAEROBIC SLUDGE LOAD IMPACT LOAD OF ORGANIC SUBSTANCES CONTAINED IN THE WHEY OF THE FERMENTATION KINETICS

    Directory of Open Access Journals (Sweden)

    Marcin Dębowski

    2014-10-01

    Full Text Available The study aimed to determine the effect of the load cell model anaerobic load of organic substances contained in the whey acidic fermentation kinetics of transformation. Specified rate of biogas production and the amount and composition of the product gas quality sludge anaerobic metabolism. The highest yield of biogas rate of 945 ml was obtained during the application of the load of 4.0 g / l, the ratio of production rate of 0.25 k 1 / d Biogas production rate increased with the increase of the initial charge of organic compounds introduced into the digester and the model was in the range from 96.3 to 236.5. Biogas composition analysis revealed that the highest concentration of methane was obtained at a load of 1.0 g / l

  3. Determination of brace forces caused by construction loads and wind loads during bridge construction.

    Science.gov (United States)

    2014-04-01

    The first objective of this study was to develop procedures for determining bracing forces during bridge construction. : Numerical finite element models and analysis techniques were developed for evaluating brace forces induced by construction loads ...

  4. Perceptual Load Affects Eyewitness Accuracy & Susceptibility to Leading Questions

    Directory of Open Access Journals (Sweden)

    Gillian Murphy

    2016-08-01

    Full Text Available Load Theory (Lavie, 1995; 2005 states that the level of perceptual load in a task (i.e. the amount of information involved in processing task-relevant stimuli determines the efficiency of selective attention. There is evidence that perceptual load affects distractor processing, with increased inattentional blindness under high load. Given that high load can result in individuals failing to report seeing obvious objects, it is conceivable that load may also impair memory for the scene. The current study is the first to assess the effect of perceptual load on eyewitness memory. Across three experiments (two video-based and one in a driving simulator, the effect of perceptual load on eyewitness memory was assessed. The results showed that eyewitnesses were less accurate under high load, in particular for peripheral details. For example, memory for the central character in the video was not affected by load but memory for a witness who passed by the window at the edge of the scene was significantly worse under high load. High load memories were also more open to suggestion, showing increased susceptibility to leading questions. High visual perceptual load also affected recall for auditory information, illustrating a possible cross-modal perceptual load effect on memory accuracy. These results have implications for eyewitness memory researchers and forensic professionals.

  5. Backpacks on! Schoolchildren's perceptions of load, associations with back pain and factors determining the load.

    Science.gov (United States)

    Negrini, Stefano; Carabalona, Roberta

    2002-01-15

    A cross-sectional study was conducted. To investigate schoolchildren's subjective perceptions of their daily backpack loads, to ascertain whether an association exists between these sensations or the load itself and back pain, and to identify the school, family, and personal factors that determine the backpack load, and that might, with a view to primary prevention, be addressed with specific interventions. Backpack carrying has been shown to constitute a considerable daily "occupational" load of the spine in schoolchildren. Although society perceives backpack carrying as a problem, the scientific community currently offers very few answers. The backpack load borne by schoolchildren exceeds, proportionally, the legal load-bearing limits set for adults, and the association with low back pain is questioned. All the backpacks of the 237 year 6 children in a school catchment area of Milan were weighed on six school days. The data were analyzed in groups according to the schools and classes involved, the single children, and the days of the week. A validated questionnaire also was administered to 115 schoolchildren (54 boys and 61 girls; average age, 11.7 years) whose anthropometric characteristics and loads carried daily were known. The associations among features of backpack carrying, subjective perceptions of the load (fatigue, feeling it to be heavy, pain) and back pain (point and life prevalence) were assessed and verified. School backpacks are felt to be heavy by 79.1% of children, to cause fatigue by 65.7%, and to cause back pain by 46.1%. Fatigue during and time spent backpack carrying, but not the backpack's weight, are associated with back pain. The determining factors were found to be classes (e.g., range, 8.87-10.59 kg), days of the week (e.g., range, 5.75-12.74 kg.), and single students (e.g., range, 4.2-9.5 kg.), but not individual schools. Daily backpack carrying is a frequent cause of discomfort for schoolchildren. There is an association between this

  6. Load alleviation potential of active flaps and individual pitch control in a full design load basis

    OpenAIRE

    Barlas, Athanasios; Bergami, Leonardo; Hansen, Morten Hartvig; Pedersen, Mads Mølgaard; Verelst, David Robert; Thomsen, Kenneth; Aagaard Madsen , Helge

    2015-01-01

    The load alleviation potential of the Controllable Rubber Trailing Edge Flap (CRTEF) is verified on a full Design Load Basis (DLB) setup using the aeroelastic code HAWC2, and by investigating a flap configuration for the NREL 5MW Reference Wind Turbine (RWT) model. The performance of the CRTEF configuration is evaluated by comparing four setups: 1) baseline with collective pitch, 2) individual pitch control, 3) individual flap control and 4) individual flap control combined with individual pi...

  7. Use of Pollutant Load Regression Models with Various Sampling Frequencies for Annual Load Estimation

    OpenAIRE

    Youn Shik Park; Bernie A. Engel

    2014-01-01

    Water quality data are collected by various sampling frequencies, and the data may not be collected at a high frequency nor over the range of streamflow conditions. Therefore, regression models are used to estimate pollutant data for days on which water quality data were not measured. Pollutant load regression models were evaluated with six sampling frequencies for daily nitrogen, phosphorus, and sediment data. Annual pollutant load estimates exhibited various behaviors by sampling frequency...

  8. Omega 3 Chia seed loading as a means of carbohydrate loading.

    Science.gov (United States)

    Illian, Travis G; Casey, Jason C; Bishop, Phillip A

    2011-01-01

    The purpose of this study was to determine if Omega 3 Chia seed loading is a viable option for enhancing sports performance in events lasting >90 minutes and allow athletes to decrease their dietary intake of sugar while increasing their intake of Omega 3 fatty acids. It has been well documented that a high dietary carbohydrate (CHO) intake for several days before competition is known to increase muscle glycogen stores resulting in performance improvements in events lasting >90 minutes. This study compared performance testing results between 2 different CHO-loading treatments. The traditional CHO-loading treatment served as the control (100% cals from Gatorade). The Omega 3 Chia drink (50% of calories from Greens Plus Omega 3 Chia seeds, 50% Gatorade) served as the Omega 3 Chia loading drink. Both CHO-loading treatments were based on the subject's body weight and were thus isocaloric. Six highly trained male subjects V(O2)max 47.8-84.2 ml · kg(-1); mean (SD) of V(O2)max 70.3 ml · kg(-1) (13.3) performed a 1-hour run at ∼65% of their V(O2)max on a treadmill, followed by a 10k time trial on a track. There were 2 trials in a crossover counterbalanced repeated-measures design with a 2-week washout between testing sessions to allow the participants to recover from the intense exercise and any effects of the treatment. There was no statistical difference (p = 0.83) between Omega 3 Chia loading (mean 10k time = 37 minutes 49 seconds) and CHO loading (mean = 37 minutes 43 seconds). Under our conditions, Omega 3 Chia loading appears a viable option for enhancing performance for endurance events lasting >90 minutes and allows athletes to decrease their dietary intake of sugar while increasing their intake of Omega 3 fatty acids but offered no performance advantages.

  9. Loading and pre-loading processes generate a distinct siRNA population in Tetrahymena

    Energy Technology Data Exchange (ETDEWEB)

    Mochizuki, Kazufumi, E-mail: kazufumi.mochizuki@imba.oeaw.ac.at; Kurth, Henriette M.

    2013-07-05

    Highlights: •The Tetrahymena Argonaute protein Twi1p binds to ∼28–30-nt siRNAs called scnRNAs. •The size of scnRNAs is determined during a pre-loading process. •The 5′ uracil bias of scnRNAs is attributed to pre-loading and loading processes. •The thermodynamic asymmetry of scnRNA duplex doesnot affect the guide strand decision. •scnRNAs may be produced non-sequentially from dsRNA substrates by Dicer. -- Abstract: The various properties of small RNAs, such as length, terminal nucleotide, thermodynamic asymmetry and duplex mismatches, can impact their sorting into different Argonaute proteins in diverse eukaryotes. The developmentally regulated 26- to 32-nt siRNAs (scnRNAs) are loaded to the Argonaute protein Twi1p and display a strong bias for uracil at the 5′ end. In this study, we used deep sequencing to analyze loaded and unloaded populations of scnRNAs. We show that the size of the scnRNA is determined during a pre-loading process, whereas their 5′ uracil bias is attributed to both pre-loading and loading processes. We also demonstrate that scnRNAs have a strong bias for adenine at the third base from the 3′ terminus, suggesting that most scnRNAs are direct Dicer products. Furthermore, we show that the thermodynamic asymmetry of the scnRNA duplex does not affect the guide and passenger strand decision. Finally, we show that scnRNAs frequently have templated uracil at the last base without a strong bias for adenine at the second base indicating non-sequential production of scnRNAs from substrates. These findings provide a biochemical basis for the varying attributes of scnRNAs, which should help improve our understanding of the production and turnover of scnRNAs in vivo.

  10. 2004 Pacific Northwest Loads and Resources Study.

    Energy Technology Data Exchange (ETDEWEB)

    United States. Bonneville Power Administration.

    2004-12-01

    The Pacific Northwest Loads and Resources Study (White Book), which is published annually by the Bonneville Power Administration (BPA), establishes one of the planning bases for supplying electricity to customers. The White Book contains projections of regional and Federal system load and resource capabilities, along with relevant definitions and explanations. The White Book also contains information obtained from formalized resource planning reports and data submittals including those from individual utilities, the Northwest Power and Conservation Council (Council), and the Pacific Northwest Utilities Conference Committee (PNUCC). The White Book is not an operational planning guide, nor is it used for determining BPA revenues, although the database that generates the data for the White Book analysis contributes to the development of BPA's inventory and ratemaking processes. Operation of the Federal Columbia River Power System (FCRPS) is based on a set of criteria different from that used for resource planning decisions. Operational planning is dependent upon real-time or near-term knowledge of system conditions that include expectations of river flows and runoff, market opportunities, availability of reservoir storage, energy exchanges, and other factors affecting the dynamics of operating a power system. The load resource balance of BPA and/or the region is determined by comparing resource availability to an expected level of total retail electricity consumption. Resources include projected energy capability plus contract purchases. Loads include a forecast of retail obligations plus contract obligations. Surplus energy is available when resources are greater than loads. This energy could be marketed to increase revenues. Energy deficits occur when resources are less than loads. These deficits could be met by any combination of the following: better-than-critical water conditions, demand-side management and conservation programs, permanent loss of loads due

  11. Use of Pollutant Load Regression Models with Various Sampling Frequencies for Annual Load Estimation

    Directory of Open Access Journals (Sweden)

    Youn Shik Park

    2014-06-01

    Full Text Available Water quality data are collected by various sampling frequencies, and the data may not be collected at a high frequency nor over the range of streamflow conditions. Therefore, regression models are used to estimate pollutant data for days on which water quality data were not measured. Pollutant load regression models were evaluated with six sampling frequencies for daily nitrogen, phosphorus, and sediment data. Annual pollutant load estimates exhibited various behaviors by sampling frequency and also by the regression model used. Several distinct sampling frequency features were observed in the study. The first was that more frequent sampling did not necessarily lead to more accurate and precise annual pollutant load estimates. The second was that use of water quality data collected from storm events improved both accuracy and precision in annual pollutant load estimates for all water quality parameters. The third was that the pollutant regression model automatically selected by LOADEST did not necessarily lead to more accurate and precise annual pollutant load estimates. The fourth was that pollutant regression models displayed different behaviors for different water quality parameters in annual pollutant load estimation.

  12. Comparison of extreme load extrapolations using measured and calculated loads of a MW wind turbine

    Energy Technology Data Exchange (ETDEWEB)

    Peeringa, J.M. [ECN Wind Energy, Petten (Netherlands)

    2009-04-15

    Since edition 3 of the standard IEC 61400-1 'Wind Turbines-Part 1; Design requirements' has been issued extreme load extrapolation during normal production is an important part of the wind turbine design and certification. At the ECN test site 'ECN Windturbine Testpark Wieringermeer' (EWTW) five in-line 2.5 MW turbines are used for research purposes. A data base with about 4 years of high quality load and meteorological measurements for a 2.5 MW wind turbine in free stream and wake conditions is available for research. This gives ECN the unique opportunity to compare extreme loads using extreme value statistics based on load simulations and load measurements for both free stream and wake conditions. Extreme load extrapolation will be applied on the flat blade root bending moment and the for aft tower bottom bending moment. Attention will be paid to the selection of the extreme value probability distribution and the amount of data needed.

  13. Comparative study of immediate functional loading and immediate non-functional loading of monocortical implants.

    Science.gov (United States)

    Singh, J P; Gupta, A K; Dhiman, R K; Roy Chowdhury, S K

    2015-12-01

    Attempts to shorten the overall length of treatment have focused on immediate loading, subsequent to implant placement. Prosthetic rehabilitation immediately after implant placement can be either functional or non-functional in nature. There is paucity of literature on the comparative evaluation of immediate functional and immediate non-functional loading of implants. This in-vivo study was undertaken to comparatively evaluate Immediate Functional Loading and Immediate Non-Functional Loading of monocortical implants with a follow-up period of 18 months. 50 partially edentulous cases were selected for the study. The cases were divided into two groups. In first group (Group-1), 25 implants were subjected to immediate functional loading. In second group (Group-2), 25 implants were subjected to immediate non-functional loading. The crestal bone loss, clinical stability and degree of osseointegration of these two groups were comparatively evaluated. The crestal bone loss in both groups was within acceptable limits. The implant stability, which is a reflection of the status of bone-to-implant interface, was comparable in both the groups at different time intervals. Although, the ISQ values in Group-2 were slightly higher than those in Group-1, the results were not statistically significant. Radiodensity indicating degree of osseointegration at different time intervals in both groups was also comparable. Both the IFL and INFL protocols can be undertaken satisfactorily in rehabilitation using endosseous implants; however, the main factors for success in IFL and INFL are case selection, meticulous treatment planning and the precision of technique.

  14. Load Balancing of Large Distribution Network Model Calculations

    Directory of Open Access Journals (Sweden)

    MARTINOVIC, L.

    2017-11-01

    Full Text Available Performance measurement and evaluation study of calculations based on load flow analysis in power distribution network is presented. The focus is on the choice of load index as it is the basic input for efficient dynamic load balancing. The basic description of problem along with the proposed architecture is given. Different server resources are inspected and analyzed while running calculations, and based on this investigation, recommendations regarding the choice of load index are made. Short description of used static and dynamic load balancing algorithms is given and the proposition of load index choice is supported by tests run on large real-world power distribution network models.

  15. Load bearing capacity of an imperfect very shallow shell

    Science.gov (United States)

    Psotny, Martin; Havran, Jozef

    2017-07-01

    Elastic shallow shell of translation subjected to the external pressure is analysed in the paper numerically by FEM. Critical loads from eigenvalue buckling analysis have been compared with load levels in limit points of nonlinear buckling analysis. Nonlinear equilibrium paths are calculated for different boundary conditions. Special attention is paid to the influence of initial imperfections on the limit load level of fundamental load-displacement path of nonlinear analysis. ANSYS system is used for analysis, arc-length method is chosen to obtain fundamental load-displacement path of solution, the reference arc-length radius is calculated from the load increment.

  16. Review of Immediate and Early Loading Protocols in Dental Implants

    Directory of Open Access Journals (Sweden)

    M Rismanchian

    2010-12-01

    Full Text Available Introduction: The concept of treating edentulous patients by osseointegrated implants was first proposed in 1960s. To minimize the failure rate of implants, it has been recommended to keep the implants free of load during the healing period .Recent studies have been directed to achieve faster integration and shorter healing periods prior to implant restoration. Loading protocols (immediate loading , early loading can best be interpreted on the biologic basis of implant integration. Each of these protocols needs special prerequisites and there are special risk factors for different loading protocols. Objectives: In this review article, different loading protocols and their surgical and prosthetic considerations are discussed.

  17. Probabilistic representation of duration of load effects in timber structures

    DEFF Research Database (Denmark)

    Svensson, Staffan

    2011-01-01

    to be considered. These two cases are maximum load level exceeding load-carrying capacity and damage accumulation (caused by the load and its duration) leading to failure. The effect of both load intensity and load duration on the capacity of timber has been an area of large interest over the last decades......-based design of timber structures in terms of a modification factor View the MathML source which is multiplied on the short-term resistance of the timber material. The scenario of a beam subject to office space life loads is analyzed and the modification factor View the MathML source is calibrated by using...

  18. Methods for estimation loads transported by rivers

    Directory of Open Access Journals (Sweden)

    T. S. Smart

    1999-01-01

    Full Text Available Ten methods for estimating the loads of constituents in a river were tested using data from the River Don in North-East Scotland. By treating loads derived from flow and concentration data collected every 2 days as a truth to be predicted, the ten methods were assessed for use when concentration data are collected fortnightly or monthly by sub-sampling from the original data. Estimates of coefficients of variation, bias and mean squared errors of the methods were compared; no method consistently outperformed all others and different methods were appropriate for different constituents. The widely used interpolation methods can be improved upon substantially by modelling the relationship of concentration with flow or seasonality but only if these relationships are strong enough.

  19. Suppressing cascades of load in interdependent networks

    CERN Document Server

    Brummitt, Charles D; Leicht, E A

    2011-01-01

    Understanding how interdependence among systems affects cascading behaviors is increasingly important across many fields of science and engineering. Inspired by cascades of load shedding in coupled electric grids and other infrastructure, we study the Bak-Tang-Wiesenfeld sandpile model on modular random graphs and on graphs based on actual, interdependent power grids. Starting from two isolated networks, adding some connectivity between them is beneficial, for it suppresses the largest cascades in each system. Too much interconnectivity, however, becomes detrimental for two reasons. First, interconnections open pathways for neighboring networks to inflict large cascades. Second, as in real infrastructure, new interconnections increase capacity and total possible load, which fuels even larger cascades. Using a multi-type branching process and simulations we show these effects and estimate the optimal level of interconnectivity that balances their tradeoffs. Such equilibria could allow, for example, power grid ...

  20. Ozone depletion and chlorine loading potentials

    Science.gov (United States)

    Pyle, John A.; Wuebbles, Donald J.; Solomon, Susan; Zvenigorodsky, Sergei; Connell, Peter; Ko, Malcolm K. W.; Fisher, Donald A.; Stordal, Frode; Weisenstein, Debra

    1991-01-01

    The recognition of the roles of chlorine and bromine compounds in ozone depletion has led to the regulation or their source gases. Some source gases are expected to be more damaging to the ozone layer than others, so that scientific guidance regarding their relative impacts is needed for regulatory purposes. Parameters used for this purpose include the steady-state and time-dependent chlorine loading potential (CLP) and the ozone depletion potential (ODP). Chlorine loading potentials depend upon the estimated value and accuracy of atmospheric lifetimes and are subject to significant (approximately 20-50 percent) uncertainties for many gases. Ozone depletion potentials depend on the same factors, as well as the evaluation of the release of reactive chlorine and bromine from each source gas and corresponding ozone destruction within the stratosphere.

  1. Microplastic deformation of polycrystals during cyclic loading

    Science.gov (United States)

    Dudarev, E. F.; Pochivalova, G. P.; Nikitina, N. V.

    1990-03-01

    A model of microplastic deformation of polycrystals during zero-start cyclic loading with tensions lower than the yield strength is proposed according to which during cycling, thermally activated movement of dislocations occurs under conditions of stress relaxation. Based on this model and the statistical theory of polycrystalline microdeformation, the accumulation of microplastic deformation is theoretically described as a function of the number of loading cycles and the stress amplitudes. It is theoretically proved that in the cycling process the microplastic deformation that accumulates over one cycle decreases as the number of cycles increases; up to the macroscopic elastic limit it is independent of the stress amplitude, and then sharply increases. Agreement of the theory with experimental data for spring alloys is observed in the density of mobile dislocations, which decreases during cycling.

  2. Soil solution sensitivity to low pollution load

    Science.gov (United States)

    Gorbacheva, Tamara; Kikuchi, Ryunosuke

    2014-05-01

    Murmansk region (Russian Federation) is included in environmental hot spots list (2003 report of NEFCO and AMAP). Annual emissions of SO2 from stationary sources (largest is Kola Mining and Metallurgical Company) and autotransport decreased in XXI century and sustained (tons) as: 282942 (2000); 2002 - 249400 (2002); 240110 (2003); 225573 (2005); 217872 (2006); 215910 (2007); 206910 (2008); 211210 (2009); 21554 (2010); 199500 (2011); 194600 (2012). Kola Peninsula terrestrial ecosystems tolerance to atmospheric S deposition was assessed on the basis of the critical load concept: most sensitive ecosystems (critical sulfur load less 400 equiv per ha per year) occupy 58% of the total area; zones at risk of excess sulfur input into ecosystems cover more than 20% of the Kola Peninsula (Koptsik et al., 2008). We attempted to estimate soil solution sensitivity to long-term, but low pollution load by sulfur dioxide in southwest direction from Monchegorsk smelter: (1) - 260 km away, 66o50,45'N; 30o 12,34'E) and (2) - 100 km away, 67o22,837'N; 32o26,016'E). The investigations were carried out during 2003-2008 period on permanent monitoring plots of INEP equipped by deposition collectors and zero-tension lyzimeters. Monitoring plots are located in similar native conditions: Site altitude - 170 m (2) vrs. 132 m (1); Forest type - Piceetum empetroso-myrtillosum-hylocomiosa; Stand history- no thining, no fires; Silvicultural history - no. Soil properties are similar too: Soil type (FAO) - ferric podzol (both plots); organic layer thickness 0-16cm (2) vrs. 0-11cm (1), E horizon thickness 16-27cm (2) vrs. 11-22cm (1), B horizon 27-51cm (2) vrs. 22-47 cm (1); parent material - glacial till (both plots). Plots are differed by annual sulfate pollution load (estimated as snow plus rain): 0.09-0.26 gm-2 (1) vrs. 0.14-0.43 gm-2(2), but both plots are refered to background plots. So, background modelled data of S deposition in the Border Areas of Norway and Russia is 0.1 - 0.2 gm-2

  3. Experimental Snap Loading of Synthetic Ropes

    Directory of Open Access Journals (Sweden)

    C.M. Hennessey

    2005-01-01

    Full Text Available Large tensile forces, known as snap loads, can occur when a slack rope becomes taut. Such forces may damage the rope or masses connected to it. Experiments are described in which one end of a rope is attached to the top of a drop tower and the bottom end is attached to a weight. The weight is raised to a certain height and then released. The force at the top of the rope and the acceleration of the weight are recorded during the first snap load that occurs. Repeated drop tests are performed on each rope. The effects of the type of rope, drop height, drop weight, whether the rope has been subjected to static precycling, and the number of previous dynamic tests are examined. A mathematical model is proposed for the rope force as a function of the displacement and velocity of the weight.

  4. 1996 Pacific Northwest Loads and Resources Study.

    Energy Technology Data Exchange (ETDEWEB)

    United States. Bonneville Power Administration.

    1996-12-01

    The Pacific Northwest Loads and Resources Study (White Book) is published annually by BPA and establishes the planning basis for supplying electricity to customers. It serves a dual purpose. First, the White Book presents projections of regional and Federal system load and resource capabilities, along with relevant definitions and explanations. Second, the White Book serves as a benchmark for annual BPA determinations made pursuant to the 1981 regional power sales contracts. Specifically, BPA uses the information in the White Book for determining the notice required when customers request to increase or decrease the amount of power purchased from BPA. Aside from these purposes, the White Book is used for input to BPA`s resource planning process. The White Book compiles information obtained from several formalized resource planning reports and data submittals, including those from the Northwest Power Planning Council (Council) and the Pacific Northwest Utilities Conference Committee (PNUCC). 11 figs., 12 tabs.

  5. DETERMINATION OF THE LOADS POSITION ON TRUCKS

    Directory of Open Access Journals (Sweden)

    César A. Chagoyén-Méndez

    2015-07-01

    Full Text Available In this paper, we presented the main problems that entail an inadequate distribution of loads on trucks and we described in detail a methodology for determining the proper position, which concludes with the completion of the installation diagrams. The methodology was obtained from the solution of the particular case of a tank of liquefied petroleum gas (LPG of 14'000 liter on a DAF CF 75.310 truck. Another result of this work is a software which allows to determine the exact position it should be the gravity center of the load relative to the front axle and the reactions on each axis, with the possibility of evaluating different variants.

  6. Yield load solutions of heterogeneous welded joints

    Energy Technology Data Exchange (ETDEWEB)

    Kozak, D., E-mail: dkozak@sfsb.h [Mechanical Engineering Faculty in Slavonski Brod, Josip Juraj Strossmayer University of Osijek, Trg Ivane Brlic-Mazuranic 2, Hr-35000 Slavonski Brod (Croatia); Gubeljak, N. [Faculty of Mechanical Engineering, University of Maribor, Smetanova 17, SI-2000 Maribor (Slovenia); Konjatic, P.; Sertic, J. [Mechanical Engineering Faculty in Slavonski Brod, Josip Juraj Strossmayer University of Osijek, Trg Ivane Brlic-Mazuranic 2, Hr-35000 Slavonski Brod (Croatia)

    2009-12-15

    The aim of this paper is to establish yield load solutions when the materials inhomogeneity within the weld is present, which is usually the case in repair welding. The effect of yield strength mismatch of welded joints performed with different geometry on the yield load value has been investigated in the context of single edge notched fracture toughness specimen subjected to bending SE(B) using the finite element method. The crack was located in the center of the weld and the two most important geometrical parameters were identified as: crack length ratio a/W as well as slenderness of the welded joint, which were systematically varied. One practical and four additional combinations of filler materials, with the same portion of overmatched part and undermatched part of the weld, were analyzed, and plane strain FE solutions for the case when the crack is located in the overmatched half of the heterogeneous weld were obtained.

  7. Hepatitis viral load correlates to glutathione levels.

    Science.gov (United States)

    1998-01-01

    Several recent scientific articles have found a direct correlation between Glutathione levels and viral activity for hepatitis B and C. When viral load increases, Glutathione decreases. Researchers from Germany report that adding NAC (N-acetyl cysteine) to HBV producing cells lines can reduce hepatitis viral load 50 fold. Glutathione is used by the liver to help break down toxins. Patients who have chronic infection for more than 90 days should ask their physicians to check their Glutathione levels. A test kit is available from ImmunoSciences Labs; contact information is included. An amino acid, L-Glutamine, can be used with Alpha Lipoic Acid and NAC to increase Glutathione levels. Chlorophyll also offers benefits to people with hepatitis and other infections. Instructions on how to use a special retention enema containing chlorophyll, water, and apple cider vinegar are provided.

  8. Rotor blade assembly having internal loading features

    Science.gov (United States)

    Soloway, Daniel David

    2017-05-16

    Rotor blade assemblies and wind turbines are provided. A rotor blade assembly includes a rotor blade having exterior surfaces defining a pressure side, a suction side, a leading edge and a trailing edge each extending between a tip and a root, the rotor blade defining a span and a chord, the exterior surfaces defining an interior of the rotor blade. The rotor blade assembly further includes a loading assembly, the loading assembly including a weight disposed within the interior and movable generally along the span of the rotor blade, the weight connected to a rotor blade component such that movement of the weight towards the tip causes application of a force to the rotor blade component by the weight. Centrifugal force due to rotation of the rotor blade biases the weight towards the tip.

  9. Loading technique for preparing radionuclide containing nanoparticles

    DEFF Research Database (Denmark)

    2011-01-01

    Source: US2012213698A The present invention relates to a novel composition and method for loading delivery systems such as liposome compositions with radionuclides useful in targeted diagnostic and/or therapy of target site, such as cancerous tissue and, in general, pathological conditions associ...... of positron emission tomography (PET) imaging technique. One specific aspect of the invention is directed to a method of producing nanoparticles with desired targeting properties for diagnostic and/or radio-therapeutic applications....

  10. Advanced Reactors Transition Program Resource Loaded Schedule

    Energy Technology Data Exchange (ETDEWEB)

    GANTT, D.A.

    2000-01-12

    The Advanced Reactors Transition (ART) Resource Loaded Schedule (RLS) provides a cost and schedule baseline for managing the project elements within the ART Program. The Fast Flux Test Facility (FETF) activities are delineated through the end of FY 2000, assuming continued standby. The Nuclear Energy (NE) Legacies and Plutonium Recycle Test Reactor (PRTR) activities are delineated through the end of the deactivation process. This revision reflects the 19 Oct 1999 baseline.

  11. Advanced Reactors Transition Program Resource Loaded Schedule

    Energy Technology Data Exchange (ETDEWEB)

    BOWEN, W.W.

    1999-11-08

    The Advanced Reactors Transition (ART) Resource Loaded Schedule (RLS) provides a cost and schedule baseline for managing the project elements within the ART Program. The Fast Flux Test Facility (FFTF) activities are delineated through the end of FY 2000, assuming continued standby. The Nuclear Energy (NE) Legacies and Plutonium Recycle Test Reactor (PRTR) activities are delineated through the end of the deactivation process. This document reflects the 1 Oct 1999 baseline.

  12. Monitoring Training Load in Indian Male Swimmers

    OpenAIRE

    MAJUMDAR, PRALAY; SRIVIDHYA, SRI

    2010-01-01

    The present study was initiated to monitor the training load with the magnitude of impact on the hormone concentrations such as testosterone, cortisol and T/C (Testosterone/Cortisol) ratio during the three phases of training (i.e. preparatory, pre-competitive, and competitive phases) in Indian male swimmers preparing for the 2010 Commonwealth Games. Blood samples were collected at the end of each training phase and hormone concentration was determined by ELISA. Our results reveal that testost...

  13. Thermal Load Calculations of Multilayered Walls

    OpenAIRE

    Bashir M. Suleiman

    2012-01-01

    Thermal load calculations have been performed for multi-layered walls that are composed of three different parts; a common (sand and cement) plaster, and two types of locally produced soft and hard bricks. The masonry construction of these layered walls was based on concrete-backed stone masonry made of limestone bricks joined by mortar. These multilayered walls are forming the outer walls of the building envelope of a typical Libyan house. Based on the periodic seasonal ...

  14. Loads as a Resource: Frequency Responsive Demand

    Energy Technology Data Exchange (ETDEWEB)

    Kalsi, Karanjit [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hansen, Jacob [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Fuller, Jason C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Marinovici, Laurentiu D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Elizondo, Marcelo A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Williams, Tess L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Lian, Jianming [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Sun, Yannan [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2015-12-01

    Current power grid operation predominantly relies on scheduling and regulating generation resources to supply loads and balance load changes. Due to the inherent intermittency of renewable energy, more flexible and fast ramping capacity is required to compensate for the uncertainty and variability introduced by renewable energy resources. With the advancement of information technologies, power system end-use loads are becoming more agile and can participate in provision of balancing energy and other grid services. The use of demand response can greatly reduce the required generation reserve in a clean and environmentally friendly way. In this report, a new frequency responsive load (FRL) controller was proposed based on the GFA controller, which can respond to both over and under-frequency events. A supervisory control was introduced to coordinate the autonomous response from FRLs in order to overcome the issues of excessive system response due to high penetration of FRLs. The effectiveness of the proposed FRL controller was demonstrated by large-scale simulation studies on the WECC system. Specifically, the FRLs were deployed in the WECC system at different penetration levels to analyze the performance of the proposed strategy both with and without supervisory level control. While both methods have their own advantages, the case without supervisory control could lead to system-wide instability depending on the size of the contingency and the number of FRLs deployed in the system. In addition, the voltage impacts of this controller on distribution system were also carefully investigated. Finally, a preliminary measurement and verification approach was also developed.

  15. Schedulers with load-store queue awareness

    Science.gov (United States)

    Chen, Tong; Eichenberger, Alexandre E.; Jacob, Arpith C.; Sura, Zehra N.

    2017-01-24

    In one embodiment, a computer-implemented method includes tracking a size of a load-store queue (LSQ) during compile time of a program. The size of the LSQ is time-varying and indicates how many memory access instructions of the program are on the LSQ. The method further includes scheduling, by a computer processor, a plurality of memory access instructions of the program based on the size of the LSQ.

  16. Prediction of Aerodynamic Loads on Rotorcraft.

    Science.gov (United States)

    1982-09-01

    OF ROTORCRAFT AND WIND TURBINES AERODYNAMIC RESEARCH ON TIPVANE WINDTURBINES by G.J.W. van Bussel, Th. van Holten and G.A.M. van Kuik AERODYNAMIC LOAD...ACTIVE CONTROLS Figure 6. Present (solid lines) and future demands on blade aerodynamic calculations. LL 5-1 AERODYNAMIC RESEARCH ON TIPVANE WINDTURBINES ...Netherlands SUMMARY Tipvanes are small auxiliary wings mounted at the tips of windturbine blades in such a way that a diffuser effect is generated

  17. Time and Cognitive Load in Working Memory

    OpenAIRE

    Barrouillet, Pierre Noël; Bernardin, Sophie; Portrat, Sophie; Vergauwe, Evie; Camos, Valérie

    2007-01-01

    International audience; According to the time-based resource-sharing model (P. Barrouillet, S. Bernardin, & V. Camos, 2004), the cognitive load a given task involves is a function of the proportion of time during which it captures attention, thus impeding other attention-demanding processes. Accordingly, the present study demonstrates that the disruptive effect on concurrent maintenance of memory retrievals and response selections increases with their duration. Moreover, the effect on recall ...

  18. A closer look at salt loaded microstructures

    OpenAIRE

    Rooij, M.R. de

    2006-01-01

    Many walls of ancient buildings are covered with plaster layers. Amongst the most recurrent causes of damage of plasters and substrates are moisture and salt decay processes. To combat these salt problems, special salt resistant plasters have been developed for application on salt loaded substrates. However, experience in the field has shown that failures regularly occur on these special mortars, making the situation little transparent for end-users. A European project called COMPASS has addr...

  19. Delamination Tolerance in Composites under Fatigue Loading

    OpenAIRE

    Singh, Lokk; Dattaguru, B.

    2013-01-01

    Delamination is one of the most commonly occurring defects in laminated composite structures. Under operating fatigue loads on the laminate this delamination could grow and totally delaminate certain number of layers from the base laminate. This will result in loss of both compressive residual strength and buckling margins available. In this paper, geometrically non-linear analysis and evaluation of Strain Energy Release Rates using MVCCI technique is presented. The problems of multiple delam...

  20. Slotted Antenna with Anisotropic Magnetic Loading

    Science.gov (United States)

    2016-07-26

    10 SLOTTED ANTENNA WITH ANISOTROPIC MAGNETIC LOADING STATEMENT OF GOVERNMENT INTEREST [0001] The invention described herein may be manufactured...therefor. CROSS REFERENCE TO OTHER PATENT APPLICATIONS [0002] None. BACKGROUND OF THE INVENTION (1) Field of the Invention [0003] The present invention ...of the VSWR curve, and modest bandwidth in each passband. SUMMARY OF THE INVENTION [0006] It is a first object of the present invention to provide