Antidepressant-like activity of Sonchus oleraceus in mouse models of immobility tests.

Science.gov (United States)

Vilela, Fabiana Cardoso; Padilha, Marina de Mesquita; Alves-da-Silva, Geraldo; Soncini, Roseli; Giusti-Paiva, Alexandre

2010-02-01

The aim of the present work is to evaluate the putative antidepressant-like effects of hydroethanolic and dichloromethanic extracts from the aerial parts of Sonchus oleraceus (Family Asteraceae) on the performance of male mice in the forced swimming test (FST) and tail suspension test (TST) models predictive of depression. The hydroethanolic and dichloromethanic extracts, both in doses of 30, 100, and 300 mg/kg, were orally administered 1 hour before carrying out the FST or the TST. The immobility time in both the FST and the TST was significantly reduced by acute oral treatment with the extracts (dose range, 100-300 mg/kg), without accompanying changes in ambulation, as assessed in an open-field test. This excluded the possibility that the effect of the extracts is due to an activation of locomotion. The efficacy of the extracts was found to be comparable to that of amitriptyline (10 mg/kg, p.o.). The present study provides evidence for an antidepressant-like effect of the active principle(s) present in the extracts of S. oleraceus in mice. Therefore, a standardized S. oleraceus extract or its purified constituents could be of potential interest for the treatment of depressive disorders.

Testing of Prototype Magnetic Suspension Cryogenic Transfer Line

Science.gov (United States)

Fesmire, J. E.; Augustynowicz, S. D.; Nagy, Z. F.; Sojourner, S. J.; Shu, Q. S.; Cheng, G.; Susta, J. T.

2006-04-01

A 6-meter prototype cryogenic transfer line with magnetic suspension was tested for its mechanical and thermal performance at the Cryogenics Test Laboratory of NASA Kennedy Space Center (KSC). A test facility with two cryogenic end-boxes was designed and commissioned for the testing. Suspension mechanisms were verified through a series of tests with liquid nitrogen. The thermal performance of the prototype was determined using the new test apparatus. The tested prototype has incorporated temperature and vacuum pressure data acquisition ports, customized interfaces to cryogenic end-boxes, and instrumentation. All tests were conducted under simulated onsite transfer line working conditions. A static (boiloff rate measurement) testing method was employed to demonstrate the gross heat leak in the tested article. The real-time temperature distribution, vacuum level, levitation distance, and mass flow rate were measured. The main purpose of this paper is to summarize the testing facility design and preparation, test procedure, and primary test results. Special arrangements (such as turning on/off mechanical support units, observing levitation gap, and setting up the flowmeter) in testing of such a magnetically levitated transfer line are also discussed. Preliminary results show that the heat leak reduction of approximately one-third to one-half is achievable through such transfer lines with a magnetic suspension system.

Suspension tests on a larger scale. Report from the status seminar on magnetic suspension techniques. Testing of the electrodynamic system started

Energy Technology Data Exchange (ETDEWEB)

Rogg, D; Muckli, W

1976-07-01

A world record speed for electromagnetically suspended vehicles as well as successful suspension tests with forced-circulation cooled superconducting magnets were the outstanding success reports at the fifth status seminar 'Magnetic suspension techniques' on 31st March and 1st April in Bad Kissingen. The research work on magnetic suspension techniques in the railborne long-distance travel is supported by the Federal Ministry of Research and Technology (BMFT) within the frameworke of the programme 'Railway engineering - New technologies'.

Involvement of monoaminergic systems in the antidepressant-like effect of Eugenia brasiliensis Lam. (Myrtaceae) in the tail suspension test in mice.

Science.gov (United States)

Colla, André R S; Machado, Daniele G; Bettio, Luis E B; Colla, Guilherme; Magina, Michele D A; Brighente, Inês M C; Rodrigues, Ana Lúcia S

2012-09-28

Several species of Eugenia L. are used in folk medicine for the treatment of various diseases. Eugenia brasiliensis is used for the treatment of inflammatory diseases, whereas Eugenia. uniflora is used for the treatment of symptoms related to depression and mood disorders, and is used in Brazil by the Guarani Indians as a tonic stimulant. To investigate the antidepressant-like effect of hydroalcoholic extracts of different plant species of genus Eugenia and to characterize the participation of the monoaminergic systems in the mechanism of action of the specie that afforded the most prominent antidepressant-like efficacy. In the first set of experiments, the effects of hydroalcoholic extracts of Eugenia beaurepaireana, Eugenia brasiliensis, Eugenia catharinae, Eugenia umbelliflora and Eugenia uniflora and the antidepressant fluoxetine (positive control) administered acutely by p.o. route were evaluated in the tail suspension test (TST) and locomotor activity was assessed in the open-field test in mice. In the second set of experiments, the involvement of the monoaminergic systems in the antidepressant-like activity of Eugenia brasiliensis was evaluated by treating mice with several pharmacological agonists and antagonists. The effects of the combined administration of sub-effective doses of Eugenia brasiliensis and the antidepressants fluoxetine, imipramine and bupropion were also evaluated. The administration of the extracts from Eugenia brasiliensis, Eugenia catharinae and Eugenia umbelliflora, but not Eugenia beaurepaireana and Eugenia uniflora, exerted a significant antidepressant-like effect, without altering locomotor activity. The behavioral profile was similar to fluoxetine. Pre-treatment of mice with ketanserin, haloperidol, SCH23390, sulpiride, prazosin and yohimbine prevented the reduction of immobility time induced by Eugenia brasiliensis. Treatment with sub-effective doses of WAY100635, SKF38393, apomorphine, phenylephrine, but not clonidine, combined

Kinetics of the QuantiFERON-TB Gold In-Tube test during treatment of patients with sputum smear-positive tuberculosis in relation to initial TST result and severity of disease

DEFF Research Database (Denmark)

Idh, Jonna; Abate, Ebba; Westman, Anna

2010-01-01

. Smear-positive TB patients (n = 71) were recruited at Gondar University Hospital, Ethiopia. The TST, QFN, CD4+ cell count and clinical symptoms (TB score) were assessed and followed up during treatment. From baseline to 7 months after treatment, there was a significant decrease in QFN reactivity (93.......8% to 62.5% in HIV-negative/TB; 70.3% to 33.3% in HIV-positive/TB patients) down to a level comparable to a control group of blood donors (51.2%). The agreement between TST and QFN was poor in TB patients compared to healthy controls. A negative TST correlated to more advanced TB in contrast to a negative...

The effect of nitrazepam on depression and curiosity in behavioral tests in mice: The role of potassium channels.

Science.gov (United States)

Nikoui, Vahid; Ostadhadi, Sattar; Azhand, Pardis; Zolfaghari, Samira; Amiri, Shayan; Foroohandeh, Mehrdad; Motevalian, Manijeh; Sharifi, Ali Mohammad; Bakhtiarian, Azam

2016-11-15

Evidence show that gamma-aminobutyric acid (GABA) receptors are involved in depression, so the aim of this study was to investigate the effect of nitrazepam as agonist of GABA A receptors on depression and curiosity in male mice and the role of potassium channel in antidepressant-like response. For this purpose, we studied the antidepressant-like properties of fluoxetine, nitrazepam, glibenclamide, and cromakalim by both forced swimming test (FST) and tail suspension test (TST). Animals were injected by various doses of nitrazepam (0.05, 0.1, and 0.5mg/kg). Nitrazepam at dose of 0.5mg/kg significantly decreased the immobility time compared to control group in both FST and TST. Fluoxetine also showed such a response. Co-administration of nitrazepam (0.05mg/kg) with glibenclamide in TST (1mg/kg) and in FST (0.3, 1mg/kg) also showed antidepressant-like response. Beside, cromakalim (0.1mg/kg) could reverse the antidepressant-like effect of nitrazepam (0.5mg/kg) in both FST and TST, while cromakalim and glibenclamide alone could not change the immobility time compared to control group (P>0.05). The hole-board test revealed that nitrazepam at doses of 0.5 and 0.1mg/kg could increase the activity of the animal's head-dipping and boost the curiosity and exploration behavior of mice. The results of this study revealed that nitrazepam may possess antidepressant-like properties and this effect is dependent to potassium channels in both FST and TST. Copyright © 2016 Elsevier B.V. All rights reserved.

EOS suspension test for the assessment of spinal flexibility in adolescent idiopathic scoliosis.

Science.gov (United States)

Hirsch, Caroline; Ilharreborde, Brice; Mazda, Keyvan

2015-07-01

The assessment of spinal flexibility is essential for the planning of adolescent idiopathic scoliosis (AIS) surgery. Various radiographic methods have been used but none of them has shown any superiority. The new low-dose stereography system EOS (EOS imaging, Paris, France) captures whole body images in a single scan without vertical distortion. EOS is now used in routine clinical use for AIS follow-up. The aim of this study was to prospectively evaluate the feasibility and the reproducibility of a new suspension test during the EOS imaging for the assessment of spinal flexibility in AIS. Fifty AIS patients scheduled for surgery were prospectively included. For each patient, a standard EOS radiograph was obtained, then a suspension test in the EOS and a classic traction test on the cotrel frame were performed. The examinations were compared in terms of radiation exposure, tolerance, mean traction force, and Cobb angle reduction for each curve. Axial and sagittal reductions during suspension were analyzed on three-dimensional EOS reconstructions. The tolerance of the suspension test was lower than the traction test but it was less operator dependent. Radiation exposure was 7 times lower during the suspension test. Cobb angle reductions achieved in the proximal and main curves by the two tests were similar. The traction test achieved greater reduction of the distal curve. Flexibility in the axial plane and in the sagittal plane was analyzed with the suspension test. The reduction in apical rotation was not correlated with the reduction in Cobb angle. The EOS suspension test can be used for the assessment of spinal flexibility in AIS. It gives a global vision of the deformity with new flexibility indices in the axial and sagittal planes.

Progress towards extreme attitude testing with Magnetic Suspension and Balance Systems

Science.gov (United States)

Britcher, Colin P.; Parker, David H.

1988-01-01

Progress is reported in a research effort aimed towards demonstration of the feasibility of suspension and aerodynamic testing of models at high angles of attack in wind tunnel Magnetic Suspension and Balance Systems. Extensive modifications, described in this paper, have been made to the Southampton University suspension system in order to facilitate this work. They include revision of electromagnet configuration, installation of all-new position sensors and expansion of control system programs. An angle of attack range of 0 to 90 deg is expected for axisymmetric models. To date, suspension up to 80 deg angle of attack has been achieved.

Antidepressant-like effects of nicotine and mecamylamine in the mouse forced swim and tail suspension tests: role of strain, test and sex

DEFF Research Database (Denmark)

Andreasen T., Jesper; Redrobe, John P

2009-01-01

, but not mecamylamine, increased swim distance in C57BL/6J mice. Both drugs increased swim distance in BALB/c mice. Effects in the mFST were independent of sex. In the mTST, mecamylamine decreased immobility in NMRI mice only, independent of sex. Nicotine was devoid of effects in the mTST, except in female C57BL/6J...

Electrochemical corrosion studies of the TStE 355 fine-grained structural steel in sulfide containing brine

International Nuclear Information System (INIS)

Farvaque-Bera, A.M.; Berg, H. von.

1994-04-01

Previous corrosion studies have shown that the unalloyed fine-grained steel TStE 355 (Material No. 1.0566) is a promising material for the manufacturing of long-lived high-level waste (HLW) containers that could act as a barrier in a rock-salt repository. Considering this fact, further electrochemical corrosion tests were performed in order to determine the influence of sulfide ions (1 -200 ppm), present as salt impurities in disposal relevant NaCl-brine (T = 55 -90 C), on the corrosion behaviour of this steel grade. For comparison, tests were carried out in the sulfide-free brine, too. (orig.) [de

Algal tests with soil suspensions and elutriates: A comparative evaluation for PAH contaminated soils

DEFF Research Database (Denmark)

Baun, Anders; Justesen, Kasper Bo; Nyholm, Niels

2002-01-01

An algal growth inhibition test procedure with soil suspensions is proposed and evaluated for PAH-contaminated soil. The growth rate reduction of the standard freshwater green alga Pseudokirchneriella subcapitata (formerly known as Selenastrum capricornutum) was used as the toxicity endpoint......, and was quantified by measuring the fluorescence of solvent-extracted algal pigments. No growth rate reduction was detected for soil contents up to 20 g/l testing five non-contaminated Danish soils. Comparative testing with PAH-contaminated soil elutriates and soil suspensions showed that the suspensions had...

QuantiFERON-TB Gold In-Tube as a Confirmatory Test for Tuberculin Skin Test in Tuberculosis Contact Tracing: A Noninferiority Clinical Trial.

Science.gov (United States)

Muñoz, Laura; Santin, Miguel; Alcaide, Fernando; Ruíz-Serrano, Maria Jesús; Gijón, Paloma; Bermúdez, Elena; Domínguez-Castellano, Angel; Navarro, María Dolores; Ramírez, Encarnación; Pérez-Escolano, Elvira; López-Prieto, María Dolores; Gutiérrez-Rodriguez, José; Anibarro, Luis; Calviño, Laura; Trigo, Matilde; Cifuentes, Carmen; García-Gasalla, Mercedes; Payeras, Antoni; Gasch, Oriol; Espasa, Mateu; Agüero, Ramon; Ferrer, Diego; Casas, Xavier; González-Cuevas, Araceli; García-Zamalloa, Alberto; Bikuña, Edurne; Lecuona, María; Galindo, Rosa; Ramírez-Lapausa, Marta; Carrillo, Raquel

2018-01-18

Screening strategies based on interferon-γ release assays in tuberculosis contact tracing may reduce the need for preventive therapy without increasing subsequent active disease. We conducted an open-label, randomized trial to test the noninferiority of a 2-step strategy with the tuberculin skin test (TST) followed by QuantiFERON-TB Gold In-Tube (QFT-GIT) as a confirmatory test (the TST/QFT arm) to the standard TST-alone strategy (TST arm) for targeting preventive therapy in household contacts of patients with tuberculosis. Participants were followed for 24 months after randomization. The primary endpoint was the development of tuberculosis, with a noninferiority margin of 1.5 percentage points. A total of 871 contacts were randomized. Four contacts in the TST arm and 2 in the TST/QFT arm developed tuberculosis. In the modified intention-to-treat analysis, this accounted for 0.99% in the TST arm and 0.51% in the TST/QFT arm (-0.48% difference; 97.5% confidence interval [CI], -1.86% to 0.90%); in the per-protocol analysis, the corresponding rates were 1.67% and 0.82% in the TST and TST/QFT arms, respectively (-0.85% difference; 97.5% CI, -3.14% to 1.43%). Of the 792 contacts analyzed, 65.3% in the TST arm and 42.2% in the TST/QFT arm were diagnosed with tuberculosis infection (23.1% difference; 95% CI, 16.4% to 30.0%). In low-incidence settings, screening household contacts with the TST and using QFT-GIT as a confirmatory test is not inferior to TST-alone for preventing active tuberculosis, allowing a safe reduction of preventive treatments. NCT01223534. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.

First results from the 'Violin-Mode' tests on an advanced LIGO suspension at MIT

International Nuclear Information System (INIS)

Lockerbie, N A; Tokmakov, K V; Carbone, L; Shapiro, B; Bell, A; Strain, K A

2011-01-01

This paper describes the first results from 'Violin-Mode' measurements made on the four suspension fibres of a fully suspended 40 kg test mass. These measurements were made at the LIGO lab, Gravitational Wave Observatory test facility, at MIT. Here, an aluminium-alloy (dummy) test mass, simulating an advanced LIGO (Laser Interferometer Gravitational Wave Observatory) test mass/mirror, had been suspended in air from a test suspension by four fused-silica suspension fibres, each measuring 400 μm in diameter x 600 mm long. Violin-Mode measurements were made on these highly tensioned fibres by retrofitting a prototype system of four novel shadow sensors to the test suspension, one per fibre, these sensors having, collectively, a displacement sensitivity of (6.9 ± 1.3) x 10 -11 m (rms) Hz -1/2 , at 500 Hz, over a measuring span of ±0.1 mm. Violin-Mode fundamental resonances were detected in all four fibres: with frequencies ∼ 485 Hz when the test mass was supported lightly from below, and at ∼500 Hz when it was fully suspended. In the latter case the Violin-Mode detection took place whilst the test mass, together with its suspension fibres, was undergoing relatively large-amplitude 'pendulum-mode' motion, at ∼0.6 Hz. This motion was measured to have a peak-peak amplitude at one of the suspension fibres of up to ∼140 μm (35 μm, rms) the shadow sensors each having subsidiary outputs for monitoring such low-frequency, large amplitude, motion. Under fully suspended conditions, a calibrated Violin-Mode 'free-oscillation' amplitude of 430 ± 20 picometres, rms, was measured at 500.875 Hz, in the same suspension fibre which was found to be undergoing, simultaneously, the ∼140 μm peak-peak motion. Over the bandwidth monitored (dc to 3.2 kHz), Violin-Mode harmonics up to the sixth were recorded in an evoked response. It was concluded that the prototype system had demonstrated amply its practical viability as a detector of Violin-Mode resonances in the test

First results from the ‘Violin-Mode’ tests on an advanced LIGO suspension at MIT

Science.gov (United States)

Lockerbie, N. A.; Carbone, L.; Shapiro, B.; Tokmakov, K. V.; Bell, A.; Strain, K. A.

2011-12-01

This paper describes the first results from ‘Violin-Mode’ measurements made on the four suspension fibres of a fully suspended 40 kg test mass. These measurements were made at the LIGO lab, Gravitational Wave Observatory test facility, at MIT. Here, an aluminium-alloy (dummy) test mass, simulating an advanced LIGO (Laser Interferometer Gravitational Wave Observatory) test mass/mirror, had been suspended in air from a test suspension by four fused-silica suspension fibres, each measuring 400 µm in diameter × 600 mm long. Violin-Mode measurements were made on these highly tensioned fibres by retrofitting a prototype system of four novel shadow sensors to the test suspension, one per fibre, these sensors having, collectively, a displacement sensitivity of (6.9 ± 1.3) × 10-11 m (rms) Hz-1/2, at 500 Hz, over a measuring span of ±0.1 mm. Violin-Mode fundamental resonances were detected in all four fibres: with frequencies ˜ 485 Hz when the test mass was supported lightly from below, and at ˜500 Hz when it was fully suspended. In the latter case the Violin-Mode detection took place whilst the test mass, together with its suspension fibres, was undergoing relatively large-amplitude ‘pendulum-mode’ motion, at ˜0.6 Hz. This motion was measured to have a peak-peak amplitude at one of the suspension fibres of up to ˜140 µm (35 µm, rms)—the shadow sensors each having subsidiary outputs for monitoring such low-frequency, large amplitude, motion. Under fully suspended conditions, a calibrated Violin-Mode ‘free-oscillation’ amplitude of 430 ± 20 picometres, rms, was measured at 500.875 Hz, in the same suspension fibre which was found to be undergoing, simultaneously, the ˜140 µm peak-peak motion. Over the bandwidth monitored (dc to 3.2 kHz), Violin-Mode harmonics up to the sixth were recorded in an evoked response. It was concluded that the prototype system had demonstrated amply its practical viability as a detector of Violin-Mode resonances in the

Measurement of ion temperature and flow in RF start-up plasmas in TST-2 and LATE

International Nuclear Information System (INIS)

Tsuda, Shintaro; Ejiri, Akira; Takase, Yuichi; Tsujii, Naoto; Takeuchi, Toshihiro; Tanaka, Hitoshi; Uchida, Masaki; Maekawa, Takashi

2015-01-01

The ion temperature and flow of RF start-up plasmas in TST-2 and LATE were measured using a visible spectrometer. The plasma currents were 9 kA and 8 kA, respectively. The typical ion temperatures T i and toroidal flow V ϕ were 4 eV and 1 km/s, respectively, in the TST-2 plasma sustained by the lower hybrid wave (20 kW) and T i ∼ 10 eV and V ϕ ∼ 5 km/s in the LATE plasma sustained by the electron cyclotron wave (50 kW). The poloidal flow velocities were comparable to the toroidal velocities. The ion temperatures were relatively high and the ion orbit loss can be significant. (author)

Lightweight superconducting magnet for a test facility of magnetic suspension for vehicles

Energy Technology Data Exchange (ETDEWEB)

Akiyama, S; Fujino, H; Onodera, K; Hirai, K

1973-01-01

Light weight superconducting magnets are required in the magnetic suspension of high speed trains. A ring shaped magnet consisting of two C-shaped superconducting coils was manufactured and tested. Twisted multifilament Nb-TI wires were used for the superconducting coils and the concept of the pipe structure for a cryostat was adopted. These improved the reliability and reduced the weight. In order to minimize the amount of heat leak into the cryostat, and FRP support with a hinge structure was used against the lift force. The superconducting coil generates a magnetomotive force of 200 kAT at a rated current of 855 A and the dimensions and weight of the whole unit are 1540 mm (outer diameter) and 560 mm (height), and 650 kG, respectively. The suspension test was done in the persistent current mode. The suspension height of 80 mm was observed at an exciting current of 800 A.

Impact of the Regulators SigB, Rot, SarA and sarS on the Toxic Shock Tst Promoter and TSST-1 Expression in Staphylococcus aureus.

Directory of Open Access Journals (Sweden)

Diego O Andrey

Full Text Available Staphylococcus aureus is an important pathogen manifesting virulence through diverse disease forms, ranging from acute skin infections to life-threatening bacteremia or systemic toxic shock syndromes. In the latter case, the prototypical superantigen is TSST-1 (Toxic Shock Syndrome Toxin 1, encoded by tst(H, and carried on a mobile genetic element that is not present in all S. aureus strains. Transcriptional regulation of tst is only partially understood. In this study, we dissected the role of sarA, sarS (sarH1, RNAIII, rot, and the alternative stress sigma factor sigB (σB. By examining tst promoter regulation predominantly in the context of its native sequence within the SaPI1 pathogenicity island of strain RN4282, we discovered that σB emerged as a particularly important tst regulator. We did not detect a consensus σB site within the tst promoter, and thus the effect of σB is likely indirect. We found that σB strongly repressed the expression of the toxin via at least two distinct regulatory pathways dependent upon sarA and agr. Furthermore rot, a member of SarA family, was shown to repress tst expression when overexpressed, although its deletion had no consistent measurable effect. We could not find any detectable effect of sarS, either by deletion or overexpression, suggesting that this regulator plays a minimal role in TSST-1 expression except when combined with disruption of sarA. Collectively, our results extend our understanding of complex multifactorial regulation of tst, revealing several layers of negative regulation. In addition to environmental stimuli thought to impact TSST-1 production, these findings support a model whereby sporadic mutation in a few key negative regulators can profoundly affect and enhance TSST-1 expression.

Plasma current start-up experiments without the central solenoid in the TST-2 spherical tokamak

International Nuclear Information System (INIS)

Takase, Y.; Ejiri, A.; Shiraiwa, S.; Adachi, Y.; Ishii, N.; Kasahara, H.; Nuga, H.; Ono, Y.; Oosako, T.; Sasaki, M.; Shimada, Y.; Sumitomo, N.; Taguchi, I.; Tojo, H.; Tsujimura, J.; Ushigome, M.; Yamada, T.; Hanada, K.; Hasegawa, M.; Idei, H.; Nakamura, K.; Sakamoto, M.; Sasaki, K.; Sato, K.N.; Zushi, H.; Nishino, N.; Mitarai, O.

2006-01-01

Several techniques for initiating the plasma current without the use of the central solenoid are being developed in TST-2. While TST-2 was temporarily located at Kyushu University, two types of start-up scenarios were demonstrated. (1) A plasma current of 4 kA was generated and sustained for 0.28 s by either electron cyclotron wave or electron Bernstein wave, without induction. (2) A plasma current of 10 kA was obtained transiently by induction using only outboard poloidal field coils. In the second scenario, it is important to supply sufficient power for ionization (100 kW of EC power was sufficient in this case), since the vertical field during start-up is not adequate to maintain plasma equilibrium. In addition, electron heating experiments using the X-B mode conversion scenario were performed, and a heating efficiency of 60% was observed at a 100 kW RF power level. TST-2 is now located at the Kashiwa Campus of the University of Tokyo. Significant upgrades were made in both magnetic coil power supplies and RF systems, and plasma experiments have restarted. RF power of up to 400 kW is available in the high-harmonic fast wave frequency range around 20 MHz. Four 200 MHz transmitters are now being prepared for plasma current start-up experiments using RF power in the lower-hybrid frequency range. Preparations are in progress for a new plasma merging experiment (UTST) aimed at the formation and sustainment of ultra-high β ST plasmas

Tuberculosis skin testing, anergy and protein malnutrition in Peru.

Science.gov (United States)

Pelly, T F; Santillan, C F; Gilman, R H; Cabrera, L Z; Garcia, E; Vidal, C; Zimic, M J; Moore, D A J; Evans, C A

2005-09-01

Malnutrition and intestinal parasites cause immunosuppression. This may cause false-negative tuberculin skin tests (TST) and failure to identify tuberculosis (TB) infection. To assess factors associated with TST positivity and anergy in disadvantaged communities in Peru. A study of 212 randomly selected adults: 102 in a rural Amazonian village and 110 shanty town residents in urban Lima. Respectively 52% and 53% of urban and rural jungle populations were TST-positive. Using simultaneous tetanus and candida skin tests, 99% had at least one positive skin test. Generalised anergy was therefore rare, despite frequent intestinal parasitic infection, including 34% helminth infection prevalence in the jungle. TST positivity was associated with age (P = 0.001), known TB contact (P = 0.02) and poor household ventilation (P = 0.007). TST positivity was not significantly associated with crowding, reported past TB, single/multiple BCG vaccination, income, intestinal parasites, dietary factors, body mass index or body fat. Individuals with lower anthropometric body protein, as measured by corrected arm muscle area, were less likely to be TST-positive (P = 0.02), implying that protein malnutrition caused tuberculin-specific anergy. These results identify the importance of household ventilation for community TB transmission and add to the evidence that protein malnutrition suppresses TB immunity, causing false-negative TST results.

Screening health care workers with interferon-γ release assay versus tuberculin skin test: impact on costs and adherence to testing (the SWITCH study).

Science.gov (United States)

Wrighton-Smith, Peter; Sneed, Laurie; Humphrey, Frances; Tao, Xuguang; Bernacki, Edward

2012-07-01

To determine the price point at which an interferon-γ release assay (IGRA) is less costly than a tuberculin skin test (TST) for health care employee tuberculosis screening. A multidecision tree-based cost model incorporating inputs gathered from time-motion studies and parallel testing by IGRA and TST was conducted in a subset of our employees. Administering a TST testing program costs $73.20 per person screened, $90.80 per new hire, and $63.42 per annual screen. Use of an IGRA for employee health testing is cost saving at an IGRA test cost of $54.83 or less per test and resulted in higher completion rates because of the elimination of the need for a second visit to interpret the TST. Using an IGRA for employee health screening can be an institutional cost saving and results in higher compliance rates.

Phosphodiesterase-1b (Pde1b) knockout mice are resistant to forced swim and tail suspension induced immobility and show upregulation of Pde10a.

Science.gov (United States)

Hufgard, Jillian R; Williams, Michael T; Skelton, Matthew R; Grubisha, Olivera; Ferreira, Filipa M; Sanger, Helen; Wright, Mary E; Reed-Kessler, Tracy M; Rasmussen, Kurt; Duman, Ronald S; Vorhees, Charles V

2017-06-01

Major depressive disorder is a leading cause of suicide and disability. Despite this, current antidepressants provide insufficient efficacy in more than 60% of patients. Most current antidepressants are presynaptic reuptake inhibitors; postsynaptic signal regulation has not received as much attention as potential treatment targets. We examined the effects of disruption of the postsynaptic cyclic nucleotide hydrolyzing enzyme, phosphodiesterase (PDE) 1b, on depressive-like behavior and the effects on PDE1B protein in wild-type (WT) mice following stress. Littermate knockout (KO) and WT mice were tested in locomotor activity, tail suspension (TST), and forced swim tests (FST). FST was also used to compare the effects of two antidepressants, fluoxetine and bupropion, in KO versus WT mice. Messenger RNA (mRNA) expression changes were also determined. WT mice underwent acute or chronic stress and markers of stress and PDE1B expression were examined. Pde1b KO mice exhibited decreased TST and FST immobility. When treated with antidepressants, both WT and KO mice showed decreased FST immobility and the effect was additive in KO mice. Mice lacking Pde1b had increased striatal Pde10a mRNA expression. In WT mice, acute and chronic stress upregulated PDE1B expression while PDE10A expression was downregulated after chronic but not acute stress. PDE1B is a potential therapeutic target for depression treatment because of the antidepressant-like phenotype seen in Pde1b KO mice.

Concordant or discordant results by the tuberculin skin test and the quantiFERON-TB test in children reflect immune biomarker profiles

DEFF Research Database (Denmark)

Dhanasekaran, S; Jenum, S; Stavrum, R

2014-01-01

The tuberculin skin test (TST) and QuantiFERON-TB-Gold-In-tube (QFTGIT) are adjunctive tests used in the diagnosis of pediatric tuberculosis (TB). Neither test can rule out TB; however, a positive test usually triggers preventive treatment in TB contacts aged <5 years. TST and QFTGIT can give div...

Non-inductive plasma initiation and plasma current ramp-up on the TST-2 spherical tokamak

International Nuclear Information System (INIS)

Takase, Y.; Ejiri, A.; Oosako, T.; Shinya, T.; Ambo, T.; Furui, H.; Kato, K.; Nakanishi, A.; Sakamoto, T.; Kakuda, H.; Wakatsuki, T.; Hashimoto, T.; Hiratsuka, J.; Kasahara, H.; Kumazawa, R.; Mutoh, T.; Saito, K.; Seki, T.; Moeller, C.P.; Nagashima, Y.

2013-01-01

Plasma current (I p ) start-up in a spherical tokamak (ST) by waves in the lower-hybrid (LH) frequency range was investigated on TST-2. A low current (∼1 kA) ST configuration can be formed by waves over a broad frequency range (21 MHz–8.2 GHz in TST-2), but further I p ramp-up (to ∼10 kA) is most efficient with waves in the LH frequency range. I p ramp-up to 15 kA was achieved with 60 kW of net RF power P RF in the fast wave (FW) polarization at 200 MHz excited by the inductively coupled combline antenna. X-ray measurements showed that the photon flux and temperature are higher in the direction opposite to I p , consistent with acceleration of electrons by a uni-directional RF wave. There is evidence that the LH wave is excited nonlinearly by the FW, based on the frequency spectra measured by magnetic probes. Similar efficiencies of I p ramp-up were obtained with the inductive combline antenna and the dielectric-loaded waveguide array (‘grill’) antenna, and tendencies for the current drive efficiency to increase with plasma current and toroidal field were observed. During operation of the grill antenna, wavevector components were measured by an array of magnetic probes. Results were qualitatively consistent with expectations based on dispersion relations for the FW and the LH wave. A capacitively coupled combline antenna has been developed to improve coupling to the plasma and the wavenumber spectrum of the excited LH wave, and will be tested in 2013. (paper)

Tuberculosis testing among populations with high HIV risk in Tijuana, Baja California, Mexico.

Science.gov (United States)

Velasquez, Michele G; Laniado-Laborin, Rafael; Rodwell, Timothy C; Cerecer, Paris; Lozada, Remedios; Cuevas-Mota, Jazmine; Burgos, Jose Luis; Garfein, Richard S

2012-07-01

To assess the prevalence of prior tuberculin skin testing (TST) among populations at risk for HIV infection in Tijuana, Mexico, and to identify factors associated with TST. Sex workers, injection drug users, noninjecting drug users, and homeless persons > 18 years old were recruited by using targeted sampling for risk assessment interviews and serologic testing for HIV and Mycobacterium tuberculosis infection. Univariate and multivariate logistic regression were used to identify correlates of self-reported TST history. Of 502 participants, 38.0% reported prior TST, which was associated with previous incarceration in the United States of America [odds ratio (OR) = 13.38; 95% confidence interval (CI) = 7.37-24.33] and injection drug use (OR = 1.99; 95% CI = 1.27- 3.11). Positive results on serologic tests for M. tuberculosis infection (57%) and HIV (4.2%) were not associated with a prior TST. A history of TST was lower in HIV-positive participants even though TST is indicated for persons with HIV in Mexico. Fewer than half the individuals at high risk for HIV in this study had a history of TST; however, TST was fairly common among those individuals with a prior history of incarceration. Increased tuberculosis screening is needed for populations at risk of contracting HIV in Tijuana, particularly those outside of criminal justice settings.

Comparison of sensitivity of quantiferon-tb gold test and tuberculin skin test in active pulmonary tuberculosis

International Nuclear Information System (INIS)

Khalil, K.F.; Ambreen, A.; Butt, T.

2013-01-01

Objective: To compare the sensitivity of tuberculin skin test (TST) and quantiFERON-TB gold test (QFT-G) in active pulmonary tuberculosis. Study Design: Analytical study. Place and Duration of Study: Department of Pulmonology, Fauji Foundation Hospital, Rawalpindi, from July 2011 to January 2012. Methodology: QuantiFERON-TB gold test (QFT-G) was evaluated and compared it with tuberculin skin test (TST) in 50 cases of active pulmonary tuberculosis, in whom tuberculous infection was suspected on clinical, radiological and microbiological grounds. Sensitivity was determined against positive growth for Mycobacterium tuberculosis. Results: Out of 50 cases, 43 were females and 7 were males. The mean age was 41.84 A+- 19.03 years. Sensitivity of QFT-G was 80% while that of TST was 28%. Conclusion: QFT-G has much higher sensitivity than TST for active pulmonary tuberculosis. It is unaffected by prior BCG administration and prior exposure to atypical mycobacteria. A positive QFT-G result can be an adjunct to diagnosis in patients having clinical and radiological data compatible with pulmonary tuberculosis. (author)

Serial testing of refugees for latent tuberculosis using the QuantiFERON-gold in-tube: effects of an antecedent tuberculin skin test.

Science.gov (United States)

Baker, Cristina A; Thomas, William; Stauffer, William M; Peterson, Phillip K; Tsukayama, Dean T

2009-04-01

Screening for latent tuberculosis infection (LTBI) in refugee populations immigrating to low-incidence countries remains a challenge. We assessed the characteristics of the QuantiFERON-Gold In-Tube (QFT-GIT) compared with the tuberculin skin test (TST) in 198 refugees of all ages from tuberculosis-endemic countries. Diagnostic agreement between the first QFT-GIT and simultaneous TST was 78% (kappa = 0.56) and between serial QFT-GITs was 89% (kappa = 0.76). In serial QFT-GIT testing, 70% of subjects had an increased QFT-GIT value, perhaps the result of an antecedent TST in the setting of previous TB exposure. This boosting seemed to become less prevalent with time from TST and occurred less frequently in those with negative first QFT-GIT readings. Despite small changes in the quantitative results caused by nonspecific variation and boosting, the diagnostic result of the QFT-GIT was reliable. The QFT-GIT shows the potential to replace the TST for LTBI screening in refugees from tuberculosis-endemic areas.

Ion temperature increase during MHD events on the TST-2 spherical tokamak

International Nuclear Information System (INIS)

Ejiri, A.; Shiraiwa, S.; Takase, Y.; Yamada, T.; Nagashima, Y.; Kasahara, H.; Iijima, D.; Kobori, Y.; Nishi, T.; Taniguchi, T.; Aramasu, M.; Ohara, S.; Ushigome, M.; Yamagishi, K.

2003-01-01

Various types of MHD events including internal reconnection events are studied on the TST-2 spherical tokamak. In weak MHD events no positive current spike was observed, but in strong MHD events with positive current spikes, a rapid and significant impurity ion temperature increase was observed. The decrease in the poloidal magnetic energy is the most probable energy source for ion heating. The plasma current shows a stepwise change. The magnitude of this step correlates with the temperature increase and is found to be a good indicator of the strength of each event. (author)

Initial results from the TST-2 spherical tokamak

International Nuclear Information System (INIS)

Takase, Y.; Ejiri, A.; Kasuya, N.

2001-01-01

A new spherical tokamak TST-2 was constructed at the University of Tokyo and started operation in September 1999. Reliable plasma initiation is achieved with typically 1 kW of ECH power at 2.45 GHz. Plasma currents of up to 90 kA and toroidal fields of up to 0.2 T have been achieved during the initial experimental campaign. The ion temperature is typically 100 eV. Internal reconnection events (IREs) are often observed. The internal magnetic field measured at r/a=2/3 indicated growth of fluctuations up to the 4 th harmonic, suggesting the existence of modes with several different mode numbers. In the presence of a toroidal field and a vertically oriented mirror field, noninductively driven currents of order 1 kA were observed with 1 kW of ECH power. The driven current increased with decreasing filling pressure, down to 3x10 -6 torr. A study of high harmonic fast wave (HHFW) excitation and propagation has begun. Initial results indicate highly efficient wave launching. (author)

Pre-employment screening of latent tuberculosis infection among healthcare workers using tuberculin skin test and QuantiFERON-TB Gold test at a tertiary care hospital in Saudi Arabia

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Mohamed El-Helaly

2014-11-01

Full Text Available Summary: Objective: To assess the agreement between the tuberculin skin test (TST and the QuantiFERON-TB Gold test (QFT-G as pre-employment screening tests for latent tuberculosis infection (LTBI among healthcare workers. Methods: A retrospective cross-sectional study was conducted among 1412 healthcare workers who were screened for LTBI during the period from August 2009 to May 2011 at a tertiary-care hospital in the Kingdom of Saudi Arabia (KSA. The studied population was screened for LTBI using both TST and QFT-G simultaneously. The agreement between both tests was quantified using the Kappa coefficient (κ. Results: Comparing the results of QFT-G with TST, the tests had a significant overall agreement of 73.7% (1040/1412; κ = 0.33; p < 0.01. Negative concordance comprised 60.1% of the results, and positive concordance comprised 13.5%. However, positive TST but negative QFT comprised 16.3% of the results, and negative TST but positive QFT-G comprised 10.1%. Concordance was significantly associated with young age, female gender, Saudi-born nationals, and early career but not job type (clinical versus non-clinical nor status of Bacillus Calmette–Guerin (BCG vaccination. Conclusions: This study demonstrated 73.7% overall agreement between TST and QFT-G results among healthcare workers during pre-employment screening for LTBI. The results need to be confirmed in future studies before recommending QFT-G as a pre-employment screening test for LTBI. Keywords: Latent tuberculosis infection, Healthcare workers, Tuberculin skin test, QuantiFERON-TB Gold test

Evaluation of the tuberculin skin test and the interferon-γ release assay for TB screening in French healthcare workers

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Raffi Francois

2009-11-01

Full Text Available Abstract Introduction Using French cut-offs for the Tuberculin Skin Test (TST, results of the TST were compared with the results of an Interferon-γ Release Assay (IGRA in Healthcare Workers (HCW after contact to AFB-positive TB patients. Methods Between May 2006 and May 2007, a total of 148 HCWs of the University Hospital in Nantes, France were tested simultaneously with IGRA und TST. A TST was considered to indicate recent latent TB infection (LTBI if an increase of >10 mm or if TST ≥ 15 mm for those with no previous TST result was observed. For those with a positive TST, chest X-ray was performed and preventive chemotherapy was offered. Results All HCWs were BCG-vaccinated. The IGRA was positive in 18.9% and TST ≥ 10 mm was observed in 65.5%. A recent LTBI was believed to be highly probable in 30.4% following TST. Agreement between IGRA and TST was low (kappa 0.041. In 10 (16.7% out of 60 HCWs who needed chest X-ray following TST the IGRA was positive. In 9 (20% out of 45 HCWs to whom preventive chemotherapy was offered following TST the IGRA was positive. Of those considered TST-negative following the French guidelines, 20.5% were IGRA-positive. In a two-step strategy - positive TST verified by IGRA - 18 out of 28 (64.3% IGRA-positive HCWs would not have been detected using French guidelines for TST interpretation. Conclusion The introduction of IGRA in contact tracings of BCG-vaccinated HCWs reduces X-rays and preventive chemotherapies. Increasing the cut-off for a positive TST does not seem to be helpful to overcome the effect of BCG vaccination on TST.

Author Details

African Journals Online (AJOL)

Comparative effects of imipramine, sertraline, nifedipine, furosemide and bumetanide on ingestive behaviour in mice. Abstract PDF · Vol 11, No 52 (2012) - Articles Effect of nifedipine, imipramine and sertraline on the antidepressant-like actions of furosemide in forced swim (FST) and tail suspension (TST) tests models of ...

Latent tuberculosis infection in individuals with human immunodeficiency virus infection: comparison of tuberculin skin test to the anti TB-IgM antibodies

International Nuclear Information System (INIS)

Alvi, S.M.; Nadimi, M.; Shokri, S.; Zamani, G.A.

2010-01-01

To determine Latent Tuberculosis Infection (LTBI) prevalence and compare TST results to the anti TB-IgM anti bodies (ATIA) for the diagnosis of LTBI in HIV infected individuals. Sixty two randomized sampled HIV infected subjects from an addict treatment center in Ahvaz southwest Iran underwent TST, using 5 TU of purified protein derivative, and measuring ATIA. Data were analyzed in SPSS (version 16, USA). Of 62 participants, 34 (54.8%) had positive result for TST, whereas 6(9.7%) had positive ATIA. Overall concordance between TST and ATIA was 45.2% (Kappa= 0.37, P = 0.32). In subjects with positive test results by either TST or ATIA, only 4.8% had positive test results by both tests. Discordant results were found in 54.8% of subjects. Positive results for both tests in subjects categorized in two groups (above and below 200 CD4-cell/mm3) had no significant difference (P>0.05). LTBI prevalence among HIV infected individuals in studied area is higher than other parts of the world. TST is a useful test for LTBI diagnosis and prefer to ATIA. Concordance between TST and ATIA is low. (author)

Characteristics of children with positive tuberculin skin test.

Science.gov (United States)

Hocaoğlu, Arzu Babayiğit; Erge, Duygu Olmez; Anal, Ozden; Makay, Balahan; Uzuner, Nevin; Karaman, Ozkan

2011-01-01

The aim of the study was to define the characteristics of children with latent tuberculosis diagnosed with positive tuberculin skin test (TST) and evaluate potential risk factors in children with positive TST. Children followed with the diagnosis of latent tuberculosis infection were included in the study retrospectively. Demographic characteristics of patients including history of atopy, respiratory infections, family history of tuberculosis and atopy, number of BCG vaccinations, findings of physical examination and laboratory data were extracted from patient's file. Eighty-one children (51 male, 30 female) who had positive TST were retrospectively evaluated in the study. Mean age of the patients was 8.00 ± 4.00 years. Only 13 (16%) of the children had contact with a case who had active tuberculosis. It was shown that the age of the patients, number of BCG scars and BCG vaccination significantly affected TST reaction size. TST size was not affected with time passed after last dose of BCG vaccination, family history of tuberculosis, presence of TST positive case in the family, exposure to cigarette smoke, number of household family members and presence of respiratory allergic disease. The patient's age, numbers of BCG vaccination and BCG scars significantly affect TST results in childhood. This may cause difficulty in diagnosing latent tuberculosis infection and in decision of initiating prophylactic treatment. The results of this study may show that recently developed, more accurate and convenient in vitro tests that they have higher costs and require sophisticated laboratory, can be used to diagnose latent tuberculosis.

Comparative efficacy of several disinfectants in suspension and carrier tests against Haemophilus parasuis serovars 1 and 5.

Science.gov (United States)

Rodríguez Ferri, E F; Martínez, S; Frandoloso, R; Yubero, S; Gutiérrez Martín, C B

2010-06-01

The comparative efficacy of 16 active compounds (including the most commonly used chemical groups) and 10 commercial formulations against Haemophilus parasuis serovars 1 and 5 was studied. These organisms were tested in suspension and carrier tests in the presence and absence of serum as representative of organic matter. Chloramine-T and half of the formulations from commercial sources (most of them including quaternary ammonium compounds) were effective in both in vitro tests, regardless of the presence or absence of organic load. All 26 disinfectants except for an iodophor (0.1% available iodine) resulted in at least 3-log(10) reduction in colony-forming units in suspension test, and most of them resulted in the maximal level of detection (>6-log(10) reduction). On the other hand, disinfectants were not as effective in carrier test as in suspension test, and the presence of serum considerably reduced the activities of most of the compounds tested, especially in carrier test. These results suggest the importance of selecting suitable disinfection for routine use on surfaces contaminated with H. parasuis, particularly when organic matter is present. Chloramine-T and formulations 2 and 7-10 are recommended for a complete inactivation of H. parasuis in swine herds. Copyright 2009 Elsevier Ltd. All rights reserved.

Structural Features and Potent Antidepressant Effects of Total Sterols and β-sitosterol Extracted from Sargassum horneri

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Donghai Zhao

2016-06-01

Full Text Available The purified total sterols and β-sitosterol extracted from Sargassum horneri were evaluated for their antidepressant-like activity using the forced swim test (FST and tail suspension test (TST in mice. Total sterols and β-sitosterol significantly reduced the immobility time in the FST and TST. Total sterols were administered orally for 7 days at doses of 50, 100, and 200 mg/kg, and β-sitosterol was administered intraperitoneally at doses of 10, 20, and 30 mg/kg. β-sitosterol had no effect on locomotor activity in the open field test. In addition, total sterols and β-sitosterol significantly increased NE, 5-HT, and the metabolite 5-HIAA in the mouse brain, suggesting that the antidepressant-like activity may be mediated through these neurotransmitters.

The decommissioning of the KEMA suspension test reactor

International Nuclear Information System (INIS)

Spruyt, A.; Peters, D.; Loon, W.M.G.M. van; Boekschoten, H.J.C.; Brugman, H.

1991-01-01

In this report the decommissioning of the KEMA Suspension Test Reactor (KSTR) is described. This reactor was a 1 MWth aqueous homo-geneous nuclear reactor in which a suspension of a mixed oxide UO 2 / ThO 2 in light water was circulated in a closed loop through a sphere-shaped core vessel. The reactor, located on KEMA premises, made 150 MW of heat during its critical periods. Dismantling of this reactor, with its many connected subsystems, meant the mastering of activated components which were also contaminated on inner surfaces caused by small fuel deposits (alpha contaminants) and fission products (beta, gamma contaminants). A description is given of the save removal of the fuel, the remote dismantling of systems and components and the disposal of steel scrap and other materials. Important features are the measures to be taken and provisions needed for safe handling, for the reduction of the radiation dose for the working team and the prevention of spreading of activity over the working area and the environment. It has been demonstrated that safe dismantling and disposal of such systems can be achieved. Experience gained at KEMA for the proper dismantling and for safety measures to be taken for workers and the environment can be made available for similar dismantling projects. A cost break-down is included in the report. (author). 22 refs.; 52 figs.; 12 tabs

An Ultra-low Frequency Modal Testing Suspension System for High Precision Air Pressure Control

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Qiaoling YUAN

2014-05-01

Full Text Available As a resolution for air pressure control challenges in ultra-low frequency modal testing suspension systems, an incremental PID control algorithm with dead band is applied to achieve high-precision pressure control. We also develop a set of independent hardware and software systems for high-precision pressure control solutions. Taking control system versatility, scalability, reliability, and other aspects into considerations, a two-level communication employing Ethernet and CAN bus, is adopted to complete such tasks as data exchange between the IPC, the main board and the control board ,and the pressure control. Furthermore, we build a single set of ultra-low frequency modal testing suspension system and complete pressure control experiments, which achieve the desired results and thus confirm that the high-precision pressure control subsystem is reasonable and reliable.

Bovine Tuberculosis in Cattle in the Highlands of Cameroon: Seroprevalence Estimates and Rates of Tuberculin Skin Test Reactors at Modified Cut-Offs

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J. Awah-Ndukum

2012-01-01

Full Text Available The aim of this study was to obtain epidemiological estimates of bovine tuberculosis (TB prevalence in cattle in the highlands of Cameroon using two population-based tuberculin skin test (TST surveys in the years 2009 and 2010. However, prior to the TST survey in 2010, blood was collected from already chosen cattle for serological assay. Anti-bovine TB antibodies was detected in 37.17% of tested animals and bovine TB prevalence estimates were 3.59%–7.48%, 8.92%–13.25%, 11.77%–17.26% and 13.14%–18.35% for comparative TST at ≥4 mm, ≥3 mm and ≥2 mm cut-off points and single TST, respectively. The agreement between TST and lateral flow was generally higher in TST positive than in TST negative subjects. The K coefficients were 0.119, 0.234, 0.251 and 0.254 for comparative TST at ≥4 mm, ≥3 mm and ≥2 mm cut-off points and the single TST groups, respectively. Chi square statistics revealed that strong (P48 associations existed between seroprevalence rates and TST reactors. The study suggested that using lateral flow assay and TST at severe interpretations could improve the perception of bovine TB in Cameroon. The importance of defining TST at modified cut-offs and disease status by post-mortem detection and mycobacterial culture of TB lesions in local environments cannot be overemphasised.

Detecting a low prevalence of latent tuberculosis among health care workers in Denmark detected by M. tuberculosis specific IFN-gamma whole-blood test

DEFF Research Database (Denmark)

Soborg, Bolette; Andersen, Aase B; Larsen, Helle K

2007-01-01

The study was designed to estimate prevalence of tuberculosis infection among health care workers, using the tuberculin skin test (TST) and the new M. tuberculosis specific diagnostic whole-blood test and to identify possible risk factors. Employees at 2 departments of infectious diseases...... as the remaining 45 TST positive participants showed no sign of active tuberculous disease and were allocated to 6-month clinical follow-up, without medical therapy. Today, 1.5 y later, all remain healthy. The high rate of positive TST among health care workers was most probably due to BCG vaccination...... TST whereas only 2 of 139 (1%) had a positive QuantiFERON TB-Gold test (QFT-TB). 42 of 106 (40%) BCG vaccinated had positive TST (> or =12 mm) compared with 2 of 27 (7%) unvaccinated persons. Among 47 persons with positive TST, 42 (89%) were BCG- vaccinated. The 2 QFT-TB positive participants as well...

Antidepressant-like property of Jobelyn®, an African unique herbal formulation, in mice.

Science.gov (United States)

Umukoro, S; Eduviere, A T; Aladeokin, A C; Olugbemide, A S

2014-03-01

The purpose of this investigation was to evaluate whether Jobelyn® (JB) possesses anti-depressant-like property in the mouse forced swimming test (FST), tail suspension test (TST) and yohimbine-induced lethality test (YLT) in aggregated mice. Mice were given JB (10-100 mg/kg, p.o.) daily for 7 days and then subjected to FST, TST, YLT and open field test. The parameters assessed in both FST and TST were the time (s) spent in active movement (struggling time), first occurrence of immobility (s) and the duration of immobility (s). In the YLT, the mortality rate was recorded 24 h after yohimbine (35 mg/kg, i.p.) administration. In the open field test, the number of line crosses and total distance travelled (m) were measured for 10 min in the open field chamber. JB significantly (popen-field test. Jobelyn® has antidepressant-like activity, which may be related to the stimulation of serotonergic and noradrenergic pathways. The ability of Jobelyn® to delay the onset of immobility and to prolong the struggling time support its use as energizer in general body weakness or exhaustion. © Georg Thieme Verlag KG Stuttgart · New York.

Modernisation of a test rig for determination of vehicle shock absorber characteristics by considering vehicle suspension elements and unsprung masses

Science.gov (United States)

Maniowski, M.; Para, S.; Knapczyk, M.

2016-09-01

This paper presents a modernization approach of a standard test bench for determination of damping characteristics of automotive shock absorbers. It is known that the real-life work conditions of wheel-suspension dampers are not easy to reproduce in laboratory conditions, for example considering a high frequency damper response or a noise emission. The proposed test bench consists of many elements from a real vehicle suspension. Namely, an original tyre-wheel with additional unsprung mass, a suspension spring, an elastic top mount, damper bushings and a simplified wheel guiding mechanism. Each component was tested separately in order to identify its mechanical characteristics. The measured data serve as input parameters for a numerical simulation of the test bench behaviour by using a vibratory model with 3 degrees of freedom. Study on the simulation results and the measurements are needed for further development of the proposed test bench.

Antidepressant-Like Activity of the Ethanolic Extract from Uncaria lanosa Wallich var. appendiculata Ridsd in the Forced Swimming Test and in the Tail Suspension Test in Mice

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Lieh-Ching Hsu

2012-01-01

Full Text Available This study investigated the antidepressant activity of ethanolic extract of U. lanosa Wallich var. appendiculata Ridsd (ULEtOH for two-weeks administrations by using FST and TST on mice. In order to understand the probable mechanism of antidepressant-like activity of ULEtOH in FST and TST, the researchers measured the levels of monoamines and monoamine oxidase activities in mice brain, and combined the antidepressant drugs (fluoxetine, imipramine, maprotiline, clorgyline, bupropion and ketanserin. Lastly, the researchers analyzed the content of RHY in the ULEtOH. The results showed that ULEtOH exhibited antidepressant-like activity in FST and TST in mice. ULEtOH increased the levels of 5-HT and 5-HIAA in cortex, striatum, hippocampus, and hypothalamus, the levels of NE and MHPG in cortex and hippocampus, the level of NE in striatum, and the level of DOPAC in striatum. Two-week injection of IMI, CLO, FLU and KET enhanced the antidepressant-like activity of ULEtOH. ULEtOH inhibited the activity of MAO-A. The amount of RHY in ULEtOH was 17.12 mg/g extract. Our findings support the view that ULEtOH exerts antidepressant-like activity. The antidepressant-like mechanism of ULEtOH may be related to the increase in monoamines levels in the hippocampus, cortex, striatum, and hypothalamus of mice.

Effect of nifedipine, imipramine and sertraline on the antidepressant ...

African Journals Online (AJOL)

The objective of the study was to determine the effect of nifedipine, imipramine and sertraline on the acute and long-term antidepressant-like responses of furosemide in the forced swim (FST) and tail suspension (TST) tests in mice. Groups of mice of six in each group were treated for 30 days with Tween 80, furosemide (10 ...

The influence of natural organic matter and aging on suspension stability in guideline toxicity testing of silver, zinc oxide, and titanium dioxide nanoparticles with Daphnia magna

DEFF Research Database (Denmark)

Cupi, Denisa; Hartmann, Nanna Isabella Bloch; Baun, Anders

2015-01-01

The present study investigated changes in suspension stability and ecotoxicity of engineered nanoparticles (ENPs) by addition of Suwannee River natural organic matter and aging of stock and test suspensions prior to testing. Acute toxicity tests of silver (Ag), zinc oxide (ZnO), and titanium...... not decrease toxicity significantly. Conversely, the presence of Suwannee River natural organic matter (NOM; 20mgL-1) completely alleviated Ag ENP toxicity in all testing scenarios and did not aid in stabilizing suspensions. In contrast, addition of Suwannee River NOM stabilized ZnO ENP suspensions and did...... in stock suspensions. The authors' results suggest that aging and presence of Suwannee River NOM are important parameters in standard toxicity testing of ENPs, which in some cases may aid in gaining better control over the exposure conditions but in other cases might contribute to agglomeration...

Safety and efficacy of the C-Tb skin test to diagnose Mycobacterium tuberculosis infection, compared with an interferon γ release assay and the tuberculin skin test: a phase 3, double-blind, randomised, controlled trial.

Science.gov (United States)

Ruhwald, Morten; Aggerbeck, Henrik; Gallardo, Rafael Vázquez; Hoff, Søren T; Villate, José I; Borregaard, Bettine; Martinez, José A; Kromann, Ingrid; Penas, Antón; Anibarro, Luis L; de Souza-Galvão, Maria Luiza; Sánchez, Francisca; Rodrigo-Pendás, Jose Ángel; Noguera-Julian, Antoni; Martínez-Lacasa, Xavier; Tuñez, Maria Victoria; Fernández, Virginia Leiro; Millet, Joan P; Moreno, Antonio; Cobos, Nazaret; Miró, José M; Roldan, Llanos; Orcau, Angels; Andersen, Peter; Caylá, Joan A

2017-04-01

Targeted screening and treatment of Mycobacterium tuberculosis infection substantially reduces the risk of developing active tuberculosis. C-Tb (Statens Serum Institute, Copenhagen, Denmark) is a novel specific skin test based on ESAT-6 and CFP10 antigens. We investigated the safety and diagnostic potential of C-Tb compared with established tests in the contact-tracing setting. Negative controls, close contacts, occasional contacts, and patients with active pulmonary tuberculosis were enrolled at 13 centres in Spain. We compared C-Tb with the QuantiFERON-TB Gold In-Tube ([QFT] Qiagen, Hilden, Germany) interferon γ release assay (IGRA) and the purified protein derivative (PPD) RT 23 tuberculin skin test ([TST] Statens Serum Institute). All participants older than 5 years were tested with QFT. Some participants in the negative control group received C-Tb without the TST to test for potential interactions between C-Tb and PPD RT 23. The rest were randomly assigned in blocks of ten and tested with both C-Tb and TST, with five in each block receiving injection of C-Tb in the right arm and the TST in the left arm and five vice versa. The primary and safety analyses were done in all participants randomly assigned to a group who received any test. This trial is registered with ClinicalTrials.gov, number NCT01631266, and with EudraCT, number 2011-005617-36. From July 24, 2012, to Oct 2, 2014, 979 participants were enrolled, of whom 263 were negative controls, 299 were occasional contacts, 316 were close contacts, and 101 were patients with tuberculosis. 970 (99%) participants completed the trial. Induration sizes were similar for C-Tb and TST, but TST positivity was affected by BCG vaccination status. We found a strong positive trend towards C-Tb test positivity with increasing risk of infection, from 3% in negative controls to 16% in occasional contacts, to 43% in close contacts. C-Tb and QFT results were concordant in 785 (94%) of 834 participants aged 5 years and older

Mycobacterium tuberculosis epitope-specific interferon-g production in healthy Brazilians reactive and non-reactive to tuberculin skin test

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Bosco Christiano Maciel da Silva

2014-12-01

Full Text Available The interferon (IFN-γ response to peptides can be a useful diagnostic marker of Mycobacterium tuberculosis (MTB latent infection. We identified promiscuous and potentially protective CD4+ T-cell epitopes from the most conserved regions of MTB antigenic proteins by scanning the MTB antigenic proteins GroEL2, phosphate-binding protein 1 precursor and 19 kDa antigen with the TEPITOPE algorithm. Seven peptide sequences predicted to bind to multiple human leukocyte antigen (HLA-DR molecules were synthesised and tested with IFN-γ enzyme-linked immunospot (ELISPOT assays using peripheral blood mononuclear cells (PBMCs from 16 Mantoux tuberculin skin test (TST-positive and 16 TST-negative healthy donors. Eighty-eight percent of TST-positive donors responded to at least one of the peptides, compared to 25% of TST-negative donors. Each individual peptide induced IFN-γ production by PBMCs from at least 31% of the TST-positive donors. The magnitude of the response against all peptides was 182 ± 230 x 106 IFN-γ spot forming cells (SFC among TST-positive donors and 36 ± 62 x 106 SFC among TST-negative donors (p = 0.007. The response to GroEL2 (463-477 was only observed in the TST-positive group. This combination of novel MTB CD4 T-cell epitopes should be tested in a larger cohort of individuals with latent tuberculosis (TB to evaluate its potential to diagnose latent TB and it may be included in ELISPOT-based IFN-γ assays to identify individuals with this condition.

Diagnosis of Latent Tuberculosis in Patients with Systemic Lupus Erythematosus: T.SPOT.TB versus Tuberculin Skin Test

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Maria Del Mar Arenas Miras

2014-01-01

Full Text Available Early studies in patients with systemic lupus erythematosus (SLE reported increased incidence of tuberculosis. The tuberculin skin test (TST is the technique of choice to detect latent tuberculosis infection (LTBI but has several limitations. Objectives. We compared TST and the newer T.SPOT.TB test to diagnose LTBI in SLE patients. Methods. In this observational cohort study conducted between August 2009 and February 2012, we recruited 92 patients from those attending the SLE clinic of our university hospital. Data recorded were epidemiological and sociodemographic characteristics. Laboratory analyses included TST and T.SPOT.TB tests. Results. Of the patients studied, 92% were women with an average age of 42.7 years. Overall, the degree of correlation between the two tests was low (Kappa index = 0.324 but was better in patients not receiving corticosteroids (CTC/immunosuppressive (IS therapy (Kappa = 0.436 and in those receiving hydroxychloroquine (Kappa = 0.473. While TST results were adversely affected by those receiving CTC and/or IS drugs (P=0.021, the T.SPOT.TB results were not. Conclusion. Although the TST test remains a useful tool for diagnosing LTBI in SLE patients, the T.SPOT.TB test is perhaps better employed when the patient is receiving CTC and/or IS drugs.

The value of counting BCG scars for interpretation of tuberculin skin tests in a tuberculosis hyperendemic shanty-town, Peru

Science.gov (United States)

Saito, M.; Bautista, C. T.; Gilman, R. H.; Bowering, A.; Levy, M. Z.; Evans, C. A.

2010-01-01

SUMMARY SETTING The tuberculin skin test (TST) is widely used as a diagnostic or screening test for Mycobacterium tuberculosis infection and disease. A peri-urban shanty-town in the desert hills of south Lima, Peru, highly endemic for tuberculosis, and where bacille Calmette-Guérin (BCG) vaccine had been given in multiple doses until 1995. OBJECTIVE To analyze the effect of multiple BCG vaccines on TST in a community-based setting. DESIGN Point-prevalence survey of TST reactions of 572 people aged 6–26 years from 255 households. TST reactions were compared to the observed number of BCG scars and other potential risk factors (age, living with a TST-positive person, and contact with active tuberculosis). RESULT People with two or more scars had significantly larger reactions, even after adjusting for potential risk factors. The adjusted population attributable fraction of being TST-positive and having two or more BCG scars was 26%. CONCLUSION There is no demonstrated benefit of repeat BCG vaccination. We therefore recommend that physicians take into consideration the number of BCG scars when interpreting the TST and that programs give no more than one BCG vaccination. PMID:15260275

RF start-up and sustainment experiments on the TST-2-K spherical tokamak

International Nuclear Information System (INIS)

Ejiri, A.; Takase, Y.; Kasahara, H.; Yamada, T.; Hanada, K.; Sato, K. N.; Zushi, H.; Nakamura, K.; Sakamoto, M.; Idei, H.; Hasegawa, M.; Iyomasa, A.; Imamura, N.; Esaki, K.; Kitaguchi, M.; Sasaki, K.; Hoshika, H.; Mitarai, O.; Nishino, N.

2006-01-01

Plasma start-up and sustainment without an inductive field have been studied in the TST-2-K spherical tokamak using high power RF sources (8.2 GHz/up to 170 kW). Steady state discharges with a plasma current of 4 kA were achieved. The line integrated density was about 3 x 10 17 m -2 and the electron temperature was 160 eV. A truncated equilibrium was introduced to reproduce magnetic measurements. It was found that a positive Pfirsch-Schlueter current in the open field line region at the outboard boundary makes a significant contribution to the current. Insensitivity of the current to variations in the vertical field and RF power variation was also found

Experimental Evaluation of Mountain Bike Suspension Systems

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J. Titlestad

2003-01-01

Full Text Available A significant distinction between competitive mountain bikes is whether they have a suspension system. Research studies indicate that a suspension system gives advantages, but it is difficult to quantify the benefits because they depend on so many variables, including the physiology and psychology of the cyclist, the roughness of the track and the design of the suspension system. A laboratory based test rig has been built that allows the number of variables in the system to be reduced and test conditions to be controlled. The test rig simulates regular impacts of the rear wheel with bumps in a rolling road. The physiological variables of oxygen consumption and heart rate were measured, together with speeds and forces at various points in the system. Physiological and mechanical test results both confirm a significant benefit in using a suspension system on the simulated rough track, with oxygen consumption reduced by around 30 % and power transmitted through the pedals reduced by 30 % to 60 %.

Evaluation of Antidepressant-like Effect of Citrus Maxima Leaves in Animal Models of Depression.

Science.gov (United States)

Potdar, Vikram H; Kibile, Swati J

2011-09-01

This study planned to assess antidepressant like activity of aqueous extract from leaves of Citrus maxima Merr. (Rutaceae). Boiling was used for aqueous extraction. Acute toxicity study was performed in mice. Antidepressant activity was studied using locomotor activity test, modified forced swimming test (FST) and tail suspension test (TST). Three doses 100, 200 and 300 mg/kg of aqueous extract of leaves were selected for testing. Fluoxetine (20 mg/kg, i.p.) and imipramine (30 mg/kg, i.p.) were used as the standard drugs. Aqueous extract of Citrus maxima leaves significantly reduced immobility time in both TST and FST. In locomotor activity testing it showed psychostimulant effect. Extract increased the climbing behavior in FST, which is similar to effect observed with imipramine. The results of this study suggest that antidepressant like effect of Citrus maxima seems to be mediated by an increase in norepinephrine level in synapses.

The Electromechanical Low-Power Active Suspension: Modeling, Control, and Prototype Testing

NARCIS (Netherlands)

Evers, W.J.E.; Teerhuis, A.P.; Knaap, van der A.C.M.; Besselink, I.J.M.; Nijmeijer, H.

2011-01-01

The high energy consumption of market-ready active suspension systems is the limiting factor in the competition with semi-active devices. The variable geometry active suspension is an alternative with a significantly lower power consumption. However, previous designs suffer from packaging problems,

The electromechanical low-power active suspension: modeling, control, and prototype testing

NARCIS (Netherlands)

Evers, W.J.; Teerhuis, A.P.; Knaap, A. van der; Besselink, I.; Nijmeijer, H.

2011-01-01

The high energy consumption of market-ready active suspension systems is the limiting factor in the competition with semi-active devices. The variable geometry active suspension is an alternative with a significantly lower power consumption. However, previous designs suffer from packaging problems,

Light-cone reduction vs. TsT transformations: a fluid dynamics perspective

Science.gov (United States)

Dutta, Suvankar; Krishna, Hare

2018-05-01

We compute constitutive relations for a charged (2+1) dimensional Schrödinger fluid up to first order in derivative expansion, using holographic techniques. Starting with a locally boosted, asymptotically AdS, 4 + 1 dimensional charged black brane geometry, we uplift that to ten dimensions and perform TsT transformations to obtain an effective five dimensional local black brane solution with asymptotically Schrödinger isometries. By suitably implementing the holographic techniques, we compute the constitutive relations for the effective fluid living on the boundary of this space-time and extract first order transport coefficients from these relations. Schrödinger fluid can also be obtained by reducing a charged relativistic conformal fluid over light-cone. It turns out that both the approaches result the same system at the end. Fluid obtained by light-cone reduction satisfies a restricted class of thermodynamics. Here, we see that the charged fluid obtained holographically also belongs to the same restricted class.

Free-Suspension Residual Flexibility Testing of Space Station Pathfinder: Comparison to Fixed-Base Results

Science.gov (United States)

Tinker, Michael L.

1998-01-01

Application of the free-suspension residual flexibility modal test method to the International Space Station Pathfinder structure is described. The Pathfinder, a large structure of the general size and weight of Space Station module elements, was also tested in a large fixed-base fixture to simulate Shuttle Orbiter payload constraints. After correlation of the Pathfinder finite element model to residual flexibility test data, the model was coupled to a fixture model, and constrained modes and frequencies were compared to fixed-base test. modes. The residual flexibility model compared very favorably to results of the fixed-base test. This is the first known direct comparison of free-suspension residual flexibility and fixed-base test results for a large structure. The model correlation approach used by the author for residual flexibility data is presented. Frequency response functions (FRF) for the regions of the structure that interface with the environment (a test fixture or another structure) are shown to be the primary tools for model correlation that distinguish or characterize the residual flexibility approach. A number of critical issues related to use of the structure interface FRF for correlating the model are then identified and discussed, including (1) the requirement of prominent stiffness lines, (2) overcoming problems with measurement noise which makes the antiresonances or minima in the functions difficult to identify, and (3) the use of interface stiffness and lumped mass perturbations to bring the analytical responses into agreement with test data. It is shown that good comparison of analytical-to-experimental FRF is the key to obtaining good agreement of the residual flexibility values.

The Twenty Statement Test in Teacher Development

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Ahmet Aypay

2011-10-01

Full Text Available The purpose of this study is to describe teacher characteristics using Twenty Statements Test (TST. Study group includes a total of thirty-five individuals, including teachers, guidance and counselors and research assistants. The study used a qualitative approach on teacher identity. TST is one of the qualitative methods that were used to determine individual self-conceptualization. Study group were requested to write twenty statements that describe themselves responding to the question “Who I am?” in a free format. The findings indicated that teachers were overwhelmingly in group c (reflective. No differences were found in terms of gender and profession. Only few significant differences have been found based on marital status. The utility of TST in teacher training and development was discussed.

The Twenty Statement Test in Teacher Development

Directory of Open Access Journals (Sweden)

Ahmet Aypay

2011-04-01

Full Text Available The purpose of this study is to describe teacher characteristics using Twenty Statements Test (TST. Study group includes a total of thirty-five individuals, including teachers, guidance and counselors and research assistants. The study used a qualitative approach on teacher identity. TST is one of the qualitative methods that were used to determine individual self-conceptualization. Study group were requested to write twenty statements that describe themselves responding to the question “Who I am?” in a free format. The findings indicated that teachers were overwhelmingly in group c (reflective. No differences were found in terms of gender and profession. Only few significant differences have been found based on marital status. The utility of TST in teacher training and development was discussed

Comparison of interferon-γ release assay to two cut-off points of tuberculin skin test to detect latent Mycobacterium tuberculosis infection in primary health care workers.

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Fernanda Mattos de Souza

Full Text Available An interferon-γ release assay, QuantiFERON-TB (QFT test, has been introduced an alternative test for the diagnosis of latent Mycobacterium tuberculosis infection (LTBI. Here, we compared the performance of QFT with tuberculin skin test (TST measured at two different cut-off points among primary health care work (HCW in Brazil.A cross-sectional study was carried out among HCWs in four Brazilian cities with a known history of high incidence of TB. Results of the QFT were compared to TST results based on both ≥5 mm and ≥10 mm as cut-off points.We enrolled 632 HCWs. When the cut-off value of ≥10 mm was used, agreement between QFT and TST was 69% (k = 0.31, and when the cut-off of ≥5 mm was chosen, the agreement was 57% (k = 0.22. We investigated possible factors of discordance of TST vs QFT. Compared to the TST-/QFT- group, risk factors for discordance in the TST+/QFT- group with TST cut-off of ≥5 mm included age between 41-45 years [OR = 2.70; CI 95%: 1.32-5.51] and 46-64 years [OR = 2.04; CI 95%: 1.05-3.93], BCG scar [OR = 2.72; CI 95%: 1.40-5.25], and having worked only in primary health care [OR = 2.30; CI 95%: 1.09-4.86]. On the other hand, for the cut-off of ≥10 mm, BCG scar [OR = 2.26; CI 95%: 1.03-4.91], being a household contact of a TB patient [OR = 1.72; CI 95%: 1.01-2.92] and having had a previous TST [OR = 1.66; CI 95%: 1.05-2.62], were significantly associated with the TST+/QFT- group. No statistically significant associations were found among the TST-/QFT+ discordant group with either TST cut-off value.Although we identified BCG vaccination to contribute to the discordance at both TST cut-off measures, the current Brazilian recommendation for the initiation of LTBI treatment, based on information gathered from medical history, TST, chest radiograph and physical examination, should not be changed.

Comparison of interferon-γ release assay to two cut-off points of tuberculin skin test to detect latent Mycobacterium tuberculosis infection in primary health care workers.

Science.gov (United States)

de Souza, Fernanda Mattos; do Prado, Thiago Nascimento; Pinheiro, Jair dos Santos; Peres, Renata Lyrio; Lacerda, Thamy Carvalho; Loureiro, Rafaela Borge; Carvalho, Jose Américo; Fregona, Geisa; Dias, Elias Santos; Cosme, Lorrayne Beliqui; Rodrigues, Rodrigo Ribeiro; Riley, Lee Wood; Maciel, Ethel Leonor Noia

2014-01-01

An interferon-γ release assay, QuantiFERON-TB (QFT) test, has been introduced an alternative test for the diagnosis of latent Mycobacterium tuberculosis infection (LTBI). Here, we compared the performance of QFT with tuberculin skin test (TST) measured at two different cut-off points among primary health care work (HCW) in Brazil. A cross-sectional study was carried out among HCWs in four Brazilian cities with a known history of high incidence of TB. Results of the QFT were compared to TST results based on both ≥5 mm and ≥10 mm as cut-off points. We enrolled 632 HCWs. When the cut-off value of ≥10 mm was used, agreement between QFT and TST was 69% (k = 0.31), and when the cut-off of ≥5 mm was chosen, the agreement was 57% (k = 0.22). We investigated possible factors of discordance of TST vs QFT. Compared to the TST-/QFT- group, risk factors for discordance in the TST+/QFT- group with TST cut-off of ≥5 mm included age between 41-45 years [OR = 2.70; CI 95%: 1.32-5.51] and 46-64 years [OR = 2.04; CI 95%: 1.05-3.93], BCG scar [OR = 2.72; CI 95%: 1.40-5.25], and having worked only in primary health care [OR = 2.30; CI 95%: 1.09-4.86]. On the other hand, for the cut-off of ≥10 mm, BCG scar [OR = 2.26; CI 95%: 1.03-4.91], being a household contact of a TB patient [OR = 1.72; CI 95%: 1.01-2.92] and having had a previous TST [OR = 1.66; CI 95%: 1.05-2.62], were significantly associated with the TST+/QFT- group. No statistically significant associations were found among the TST-/QFT+ discordant group with either TST cut-off value. Although we identified BCG vaccination to contribute to the discordance at both TST cut-off measures, the current Brazilian recommendation for the initiation of LTBI treatment, based on information gathered from medical history, TST, chest radiograph and physical examination, should not be changed.

Tuberculin Skin Testing

Science.gov (United States)

... Appendix 1 Appendix 2 Appendix 3 Interim Laboratory Biosafety Guidance for XDR Mycobacterium tuberculosis strains Data & Statistics ... The Mantoux tuberculin skin test (TST) is the standard method of determining whether a person is infected ...

The behaviour of a vehicle’s suspension system on dynamic testing conditions

Science.gov (United States)

Mihon, L.; Lontiş, N.; Deac, S.

2018-01-01

The paper presents a car suspension’s behaviour on dynamic testing conditions through theoretical and mathematical simulation on specific model, on the single traction wheel, according to the real vehicle and by experiment on the test bench by reproducing the road’s geometry and vehicle’s speed and measuring the acceleration and damping response of the suspension system on that wheel. There are taking in consideration also the geometry and properties of the tyre-wheel model and physical wheel’s properties. The results are important due to the suspension’s model properties which allows to extend the theory and applications to the whole vehicle for improving the vehicle’s dynamics.

Association between parasitic infections and tuberculin skin test results in refugees.

Science.gov (United States)

Watts, Nathaniel S; Mizinduko, Mucho M; Barnett, Elizabeth D; White, Laura F; Hochberg, Natasha S

Parasitic infections are known to modulate the immune response necessary for controlling Mycobacterium tuberculosis infection. We sought to investigate species-specific effects of parasite infection on M. tuberculosis infection. As part of the Refugee Health Assessment Program, stool examinations and tuberculin skin testing were performed on refugees seen at Boston Medical Center between 1995 and 2012. Tuberculin skin test (TST) and stool examination data were collected for 6669 refugees; 3349 (50.2%) were TST positive (≥10 mm). Among TST-positive subjects, 176 (5.3%) had helminth infections and 1149 (34.3%) protozoa. After adjusting for sex, age, and country of origin, helminth and protozoan infections were not associated with TST-positivity. When species-specific effects were examined, subjects infected with Trichuris trichiura and Giardia lamblia had reduced odds of TST-positivity (adjusted OR [aOR] 0.65 [95%CI 0.44-0.96; p = 0.03] and aOR 0.79 [95%CI 0.65-0.95, p = 0.01], respectively). Our findings suggest that T. trichiura and G. lamblia may provide protection against M. tuberculosis infection. This study adds to a growing body of literature suggesting that immune response modulation and susceptibility to M. tuberculosis infection is parasite species-dependent. Copyright © 2017 Elsevier Ltd. All rights reserved.

Teste tuberculínico. Como optimizar?

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Raquel Duarte

2009-03-01

Full Text Available Resumo: Os testes utilizados no diagnóstico de infecção latente pelo Mycobacterium tuberculosis, o teste tuberculínico e o doseamento do interferão gama (IGRA identificam a existência de uma resposta imunológica adaptativa de memória contra os antigénios micobacterianos. Considerando as limitações dos dois testes, a melhor solução passa por tirar proveito das melhores características de cada um. A maior parte dos autores concorda com a utilização dos dois testes, utilizando os IGRA sobretudo na confirmação da positividade do teste tuberculínico (tirando proveito da sua maior especificidade.As características operativas do teste tuberculínico dependem da prevalência da doença na comunidade e dos objectivos da sua realização (as suas características são superiores quando utilizada no âmbito de rastreio ou como teste diagnóstico. Para interpretar correctamente um teste tuberculínico, o clínico deve conhecer a epidemiologia da tuberculose na comunidade e definir correctamente as indicações para a sua realização. Abstract: The tests used in the diagnosis of tuberculosis latent infection, the tuberculin skin test (TST and the interferon-gamma assays (IGRA, identify the existence of an adaptive immune response towards mycobacterial antigens. Considering the limitations of the two tests, the best solution is to take advantage of the best characteristics of each one. Most of the authors agree to the use of the two tests, using the IGRAS in the confirmation of a positive TST (because of its higher specificity. The operative characteristics of TST depend on the prevalence of the illness in the community and the aim of its use (its operative characteristics are higher when used in the tracing scope or as a diagnostic test. To interpret correctly a TST, the physician must know the epidemiology of tuberculosis in the community and correctly define the indications for its use. Palavras-chave: Tuberculose, teste tubercul

Experimental evaluation of Hiṅgvādi Ghṛta in behavioral despair using animal models

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Poonam Ashish Gupte

2016-01-01

Full Text Available Context: Depression, a sustained mood disorder caused by selective diminution of specialized cells in brain is increasing at an alarming rate. It will be the second largest morbid illness by next decade and is the leading cause of suicidal deaths. The available antidepressant medications benefit only a third of its recipients and have many side effects. Hence, it is imperative to search in Ayurveda for leads. Aim: To evaluate Anti- depressant activity of Hiṅgvādi Ghṛta in vivo. Settings and Design: Comparative preclinical study. Materials and Methods: Hiṅgvādi Ghṛta (HG was prepared using standard operating procedure, physicochemically analyzed and assessed. Tail Suspension Test (TST model with Swiss albino mice and Forced Swim Test (FST model with Wistar albino rats were used to assess anti-depressant activity. Imipramine hydrochloride in dose of 15 mg/kg for TST and 10 mg/kg for FST, was the standard drug and Ghee as vehicle control in dose of 0.1g/20g for TST and 0.72g/200g for FST orally. Hiṅgvādi Ghṛta in doses of 0.05g/20g (x/2, 0.1g/20g (x and 0.2 g/20g (2x for TST and 0.36g/200g (x/2, 0.72g/200g (x and 1.44g/200g (2x for FST was administered to 3 test groups for 21 days orally except Plain control group which received only distilled water. Duration of immobility in seconds for TST and number of rotations for FST were noted for assessment. Statistical Analysis Used: One way ANOVA followed by Dunnets test and Paired t test. Results: HG was significantly effective at dose of 0.1gm/20gm for TST (P = 0.0037; P < 0.01 and 0.72g/200g for FST (P = 0.0055, P < 0.01 comparable to Imipramine hydrochloride. Conclusions: HG displayed potent anti depressant activity comparable to standard drug Imipramine Hydrochloride.

Development of A New Automotive Active Suspension System

Science.gov (United States)

Yousef Abdulhammed, Eng.; Eng. Hisham Elsherif, Dr, Prof.

2017-12-01

The main objective was to develop a smart new vehicle suspension system that minimizes the road irregularities impact on the driver, also to increase performance and stability of the vehicle at high speeds. The central idea is based on modifying the normal passive suspension system into a computer controller hydraulic actuated active suspension system simply by adding a new component such as a hydraulic cylinder on a normal passive system. The new suspension system is economical to be wildly used in consumer’s cars with low prices. The new added components was analytically tested and modeled according to different parameters. A new test rig was implemented to simulate a real quarter suspension system. The new suspension model was controlled by feedback controller according to the road conditions; the controller output controls the cylinder actuator to compensate the road oscillations and increases the vehicle stability for the passenger. Finally, to maximize the aerodynamics coefficients of the vehicle during high speeds by controlling the vehicle clearance level from the ground to achieve full stability, steering and fuel economy.

Screening of latent tuberculosis infection among health care workers working in Hajj pilgrimage area in Saudi Arabia, using interferon gamma release assay and tuberculin skin test.

Science.gov (United States)

Bukhary, Zakeya A; Amer, Soliman M; Emara, Magdy M; Abdalla, Mohammad E; Ali, Sahar A

2018-01-01

Interferon gamma release assays (IGRA) is highly specific for Mycobacterium tuberculosis and is the preferred test in BCG-vaccinated individuals. The few studies that have screened health care workers (HCWs) in Saudi Arabia for latent tuberculosis infection (LTBI) using IGRA have varied in agreement with the traditional tuberculin skin test (TST). Assess the prevalence of LTBI among HCWs working in the Hajj pilgrimage using IGRA and TST and measuring their agreement. Cross-sectional prospective. Multiple non-tertiary care hospitals. HCWs who worked during the Hajj pilgrimage in Saudi Arabia in December 2015. Data was collected by standarized questionnaire. Samples were drawn and analyzed by standard methods. The prevalence of LTBI among HCW and the agreement by kappa statistic between QFT-GIT and TST. 520 subjects. Nurses accounted for 30.7% of the sample and physicians, 19.2%. The majority were BCG vaccinated (98.5%). There were a total of 56 positive by QFT-GIT and the LTBI rate was 10.8%. In 50 QFT positive/476 TST negative the LTBI rate was 10.5% in discordant tests, and in 6 QFT positive/44 TST positive it was 13.6% in concordant tests. The overall agreement between both tests was poor-83% and kappa was 0.02. LTBI prevalence was associated with longer employment (13.1 [9.2] years). The QFT-GIT positive test was significantly higher in physicians (P=.02) and in HCWs working in chest hospitals 16/76 (21.05%) (P=.001). Agreement between the tests was poor. QFT-GIT detected LTBI when TST was negative in HCWs who had a history of close contact with TB patients. A second step TST was not feasible within 2-3 weeks. None.

[Tuberculosis screening program for undocumented immigrant teenagers using the QuantiFERON(®)-TB Gold In-Tube test].

Science.gov (United States)

Salinas, Carlos; Ballaz, Aitor; Díez, Rosa; Aguirre, Urko; Antón, Ane; Altube, Lander

2015-07-06

The aim of this study was to determine the prevalence of tuberculosis infection in undocumented immigrant teenagers using a tuberculin skin test (TST) for initial screening and QuantiFERON(®)-TB Gold In-Tube (QFT-GIT) as a confirmatory test. From 2007 to 2012, under 19 year-old immigrant teenagers from 2 accommodation centers of the Basque Country (Spain) were included in the study. The TST was done in all of them and the QFT-GIT was done in selected patients with a TST≥5mm. Eight hundred and forty-five immigrants were included, most of them from Africa (99.5%). Fifty-one percent of immigrants with TST ≥ 5 mm has a positive QFT-GIT. We found 2 cases of active tuberculosis (2/845: 0.24%). The concordance between TST (≥ 10 mm) and QFT-GIT was 63%, with 57% of positive concordance cases and 96% of negative concordances. There were 246 cases with TST ≥ 10 mm (29%), with significant differences between Magrebis (21.5%) and Subsaharians (67%) (Ptuberculosis infection in Subsaharian immigrants, we recommend implementing screening programs in this population. Using QFT-GIT, the number of candidates for chemoprophylaxis was reduced to 43% compared with TST alone (≥ 10 mm). Copyright © 2013 Elsevier España, S.L.U. All rights reserved.

Comparison of two interferon-gamma assays and tuberculin skin test for tracing tuberculosis contacts

NARCIS (Netherlands)

Arend, Sandra M.; Thijsen, Steven F. T.; Leyten, Eliane M. S.; Bouwman, John J. M.; Franken, Willeke P. J.; Koster, Ben F. P. J.; Cobelens, Frank G. J.; van Houte, Arend-Jan; Bossink, Ailko W. J.

2007-01-01

The tuberculin skin test (TST) has low specificity. QuantiFERON-TB Gold (QFT-G) and T-SPOT.TB are based on interferon (IFN)-gamma responses to Mycobacterium tuberculosis-specific antigens. A novel in-tube format of QFT-G (QFT-GIT) offers logistical advantages. To compare TST, QFT-GIT, and T-SPOT.TB

Detecting a low prevalence of latent tuberculosis among health care workers in Denmark detected by M. tuberculosis specific IFN-gamma whole-blood test

DEFF Research Database (Denmark)

Soborg, Bolette; Andersen, Aase B; Larsen, Helle K

2007-01-01

The study was designed to estimate prevalence of tuberculosis infection among health care workers, using the tuberculin skin test (TST) and the new M. tuberculosis specific diagnostic whole-blood test and to identify possible risk factors. Employees at 2 departments of infectious diseases...... as the remaining 45 TST positive participants showed no sign of active tuberculous disease and were allocated to 6-month clinical follow-up, without medical therapy. Today, 1.5 y later, all remain healthy. The high rate of positive TST among health care workers was most probably due to BCG vaccination...

Qualification criteria verification for aisi-4340 steel suspension lug

International Nuclear Information System (INIS)

Riaz, M.A.; Alam, M.

2005-01-01

All external loads carried underneath an aircraft are mounted onto it through mechanism generally known as suspension system. The externally mounted attachments like bombs, missiles and fuel tanks etc. experience enormous aerodynamic and inertial forces in the flights. These forces are transferred to the interface point of suspension system, known as 'Suspension Lug'. Thus lugs are considered critical component and have extremely stringent qualification criteria standards used in the aviation industry in USA, Europe, Russia, etc. Different standards prevail in different parts of the world about qualification and testing of these lugs. As Pakistan is entering into aviation industry, therefore there is a need to fulfill the requirements of these standards, to suit Pakistani environment. The suspension lug under study is 2000 Ibs. load class made from AISI-4340 Steel having good mechanical properties as per required standard. The manufacturing processes included forging, machining and vacuum heat treatment. The prototypes of suspension lugs were manufactured in the local industry and subjected to the required mechanical tests such as tensile testing at 5 to 35 degree angles. Impact testing at cryogenic temperatures of -50 to -70 degree C, and breaking load testing were performed. The acceptable results were obtained and mechanical testing for qualification of lugs was finalized and standardized. The options were compared with practical viability, utilization of product and cost effectiveness. (author)

Administrative license suspension: Does length of suspension matter?

Science.gov (United States)

Fell, James C; Scherer, Michael

2017-08-18

Administrative license revocation (ALR) laws, which provide that the license of a driver with a blood alcohol concentration at or over the illegal limit is subject to an immediate suspension by the state department of motor vehicles, are an example of a traffic law in which the sanction rapidly follows the offense. The power of ALR laws has been attributed to how swiftly the sanction is applied, but does the length of suspension matter? Our objectives were to (a) determine the relationship of the ALR suspension length to the prevalence of drinking drivers relative to sober drivers in fatal crashes and (b) estimate the extent to which the relationship is associated to the general deterrent effect compared to the specific deterrent effect of the law. Data comparing the impact of ALR law implementation and ALR law suspension periods were analyzed using structural equation modeling techniques on the ratio of drinking drivers to nondrinking drivers in fatal crashes from the Fatality Analysis Reporting System (FARS). States with an ALR law with a short suspension period (1-30 days) had a significantly lower drinking driver ratio than states with no ALR law. States with a suspension period of 91-180 days had significantly lower ratios than states with shorter suspension periods, while the three states with suspension lengths of 181 days or longer had significantly lower ratios than states with shorter suspension periods. The implementation of any ALR law was associated with a 13.1% decrease in the drinking/nondrinking driver fatal crash ratio but only a 1.8% decrease in the intoxicated/nonintoxicated fatal crash ratio. The ALR laws and suspension lengths had a significant general deterrent effect, but no specific deterrent effect. States might want to keep (or adopt) ALR laws for their general deterrent effects and pursue alternatives for specific deterrent effects. States with short ALR suspension periods should consider lengthening them to 91 days or longer.

Fluoxetine treatment induces dose dependent alterations in depression associated behavior and neural plasticity in female mice

OpenAIRE

Hodes, Georgia E.; Hill-Smith, Tiffany E.; Lucki, Irwin

2010-01-01

Antidepressant induced increases in neurogenesis and neurotrophin mobilization in rodents and primates are proposed to be necessary for behavioral efficacy. The current study examines the relationship between the effects of fluoxetine treatment on behavior, cell proliferation and the neurotrophin BDNF in females. Female MRL/MpJ mice were treated acutely (5 and 10 mg/kg) or chronically (2.5, 5 and 10 mg/kg b.i.d.) with fluoxetine and tested in the tail suspension test (TST) and or novelty indu...

Evaluation of antidepressant activity of vanillin in mice.

Science.gov (United States)

Shoeb, Ahsan; Chowta, Mukta; Pallempati, Gokul; Rai, Amritha; Singh, Ashish

2013-01-01

The main objective of this study was to evaluate antidepressant activity of vanillin in mice models of depression. Animals were divided into five groups, consisting six mice in each group. Out of these, three groups served as control (distilled water, imipramine,and fluoxetine) and the remaining two groups received test drug in two different doses (10 mg/kg and 100 mg/kg). All the drugs were administered orally one hour before the test procedure for acute study and daily for ten days for chronic study. Mice were subjected to forced swim (FST) and tail suspension tests (TST). Both the doses of vanillin reduced the immobility duration in TST as well as in FST. In TST, there was a statistically significant decrease in the immobility in all the groups when compared to the control (distilled water) group. But the reduction of immobility in FST did not show statistically significant reduction in immobility in the groups treated with vanillin when compared with control. In the chronic study group that received vanillin at a dose of 100 mg/kg, the immobility reduction was significantly lower when compared to the group receiving fluoxetine. Vanillin at the dosage of 100 mg/kg has demonstrated antidepressant activity in mice, which is comparable with fluoxetine.

Involvement of the Cerebral Monoamine Neurotransmitters System in Antidepressant-Like Effects of a Chinese Herbal Decoction, Baihe Dihuang Tang, in Mice Model

Directory of Open Access Journals (Sweden)

Meng-Li Chen

2012-01-01

Full Text Available Baihe Dihuang Tang (BDT is a renowned Chinese herbal formula which is commonly used for treating patients with mental instability, absentmindedness, insomnia, deficient dysphoria, and other psychological diseases. These major symptoms closely associated with the depressive disorders. BDT was widely popular use for treating emotion-thought disorders for many years in China. In the present study, the antidepressant-like effect of BDT in mice was investigated by using the forced swim test (FST and the tail suspension test (TST. The underlying mechanism was explored by determining the effect of BDT on the level of cerebral monoamine neurotransmitters. BDT (9 and 18 g/kg, p.o. for 14 days administration significantly reduced the immobility time in both the FST and the TST without changing locomotion in the open field-test (OFT. Moreover, BDT treatment at the dose of 18 g/kg inhibited reserpine-induced ptosis. Meanwhile, BDT enhanced 5-HT and NA levels in mouse cerebrum as well as decreased the ratio of 5-HT compared to its metabolite, 5-HIAA, (turnover, 5-HIAA/5-HT after TST. The results demonstrated that the antidepressant-like effect of BDT is mediated, at least partially, via the central monoaminergic neurotransmitter system.

Gemfibrozil has antidepressant effects in mice: Involvement of the hippocampal brain-derived neurotrophic factor system.

Science.gov (United States)

Ni, Yu-Fei; Wang, Hao; Gu, Qiu-Yan; Wang, Fei-Ying; Wang, Ying-Jie; Wang, Jin-Liang; Jiang, Bo

2018-04-01

Major depressive disorder has become one of the most serious neuropsychiatric disorders worldwide. However, currently available antidepressants used in clinical practice are ineffective for a substantial proportion of patients and always have side effects. Besides being a lipid-regulating agent, gemfibrozil is an agonist of peroxisome proliferator-activated receptor-α (PPAR-α). We investigated the antidepressant effects of gemfibrozil on C57BL/6J mice using the forced swim test (FST) and tail suspension test (TST), as well as the chronic unpredictable mild stress (CUMS) model of depression. The changes in brain-derived neurotrophic factor (BDNF) signaling cascade in the brain after CUMS and gemfibrozil treatment were further assessed. Pharmacological inhibitors and lentivirus-expressed short hairpin RNA (shRNA) were also used to clarify the antidepressant mechanisms of gemfibrozil. Gemfibrozil exhibited significant antidepressant actions in the FST and TST without affecting the locomotor activity of mice. Chronic gemfibrozil administration fully reversed CUMS-induced depressive-like behaviors in the FST, TST and sucrose preference test. Gemfibrozil treatment also restored CUMS-induced inhibition of the hippocampal BDNF signaling pathway. Blocking PPAR-α and BDNF but not the serotonergic system abolished the antidepressant effects of gemfibrozil on mice. Gemfibrozil produced antidepressant effects in mice by promoting the hippocampal BDNF system.

Private sector tuberculosis prevention in the US: Characteristics associated with interferon-gamma release assay or tuberculin skin testing.

Science.gov (United States)

Stockbridge, Erica L; Miller, Thaddeus L; Carlson, Erin K; Ho, Christine

2018-01-01

To determine whether latent tuberculosis infection risk factors are associated with an increased likelihood of latent tuberculosis infection testing in the US private healthcare sector. A national sample of medical and pharmacy claims representing services rendered January 2011 through December 2013 for 3,997,986 commercially insured individuals in the US who were 0 to 64 years of age. We used multivariable logistic regression models to determine whether TB/LTBI risk factors were associated with an increased likelihood of Interferon-Gamma Release Assay (IGRA) or Tuberculin Skin Test (TST) testing in the private sector. 4.31% (4.27-4.34%) received at least one TST/IGRA test between 2011 and 2013 while 1.69% (1.67-1.72%) received a TST/IGRA test in 2013. Clinical risk factors associated with a significantly increased likelihood of testing included HIV, immunosuppressive therapy, exposure to tuberculosis, a history of tuberculosis, diabetes, tobacco use, end stage renal disease, and alcohol use disorder. Other significant variables included gender, age, asthma, the state tuberculosis rate, population density, and percent of foreign-born persons in a county. Private sector TST/IGRA testing is not uncommon and testing varies with clinical risk indicators. Thus, the private sector can be a powerful resource in the fight against tuberculosis. Analyses of administrative data can inform how best to leverage private sector healthcare toward tuberculosis prevention activities.

Interferon Gamma Release Assay versus Tuberculin Skin Testing among Healthcare Workers of Highly Diverse Origin in a Moderate Tuberculosis Burden Country.

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Sahal Al Hajoj

Full Text Available Health care workers (HCW's are always at an increased risk of contracting tuberculosis (TB infection. In Saudi Arabia, Interferon Gamma Release Assay (IGRA has not been evaluated as a screening tool for latent TB infection (LTBI among HCW's considering their high demographic diversity. During February 2012 to January 2015 a cross sectional study has been conducted in a tertiary care center with maximum demographically diverse staff population in the capital city-Riyadh. After a short interview and consenting, all the candidates were subjected to tuberculin skin test (TST and QuantiFERON TB gold In-tube test (QFT. A logistic regression analysis was carried out for establishing the associations between putative risk factors and the diagnostic tests. The candidates were classified according to geographical origin and a detailed analysis was conducted on the impact of their origin towards the results of TST and QFT. Of the 1595 candidates enrolled, 90.6% were BCG vaccinated, female (67.9% and mainly nurses (53.2%. Candidates with high risk of suspected or confirmed TB patient exposure were 56.1% and 76.5% of them had <10 year's work experience. TST positivity was observed in 503 (31.5% candidates, while QFT was positive among 399 (25%. Majority of the candidates were non-Saudi (83% and predominantly (52.4% from Western Pacific region. Concordant results were obtained in 14.2% of positive cases and 57.7% negative cases. The disagreements between the two tests were relatively high (kappa co-efficient-0.312±0.026, p value- <0.00001 as TST positive/QFT negative discordance was 54.8% while TST negative/QFT positive discordance was 15.7%. Age of the candidates, BCG vaccination, and South East Asian origin were associated with TST positivity while Occupational TB exposure and geographical origin of the candidates were associated with QFT positivity. A regular follow up on recently TST converted candidates showed no progression to active TB. The putative

Safety of the two-step tuberculin skin test in Indian health care workers.

Science.gov (United States)

Christopher, Devasahayam J; Shankar, Deepa; Datey, Ashima; Zwerling, Alice; Pai, Madhukar

2014-12-01

Health care workers (HCW) in low and middle income countries are at high risk of nosocomial tuberculosis infection. Periodic screening of health workers for both TB disease and infection can play a critical role in TB infection control. Occupational health programs that implement serial tuberculin skin testing (TST) are advised to use a two-step baseline TST. This helps to ensure that boosting of waned immune response is not mistaken as new TB infection (i.e. conversion). However, there are no data on safety of the two-step TST in the Indian context where HCWs are repeatedly exposed. Nursing students were recruited from 2007 to 2009 at the Christian Medical College and Hospital, Vellore, India. Consenting nursing students were screened with a baseline two-step TST at the time of recruitment. From 2007 to 2008 adverse events were recorded when reported during the TST reading (Cohort A). Nurses recruited in the final study year (2009) answered an investigator administered questionnaire assessing all likely side-effects Cohort B). This information was extracted from the case report forms and analysed. Between 2007 and 09, 800 trainees consented to participate in the annual TB screening study and 779 did not have a past history of TB or recall a positive TST and were selected to administer TST. Of these, 755 returned for reading the result and had complete data and were included for the final analysis - 623 subjects in (cohort A) and 132 in (cohort B). These were included for the final analysis. In cohort A only 1.3% reported adverse events. In cohort B, as per the investigator administered questionnaire; 25% reported minor side effects. Itching and local pain were the most common side effects encountered. There were no major adverse events reported. In particular, the adverse events were similar in the second step of the test and not more severe. Screening of HCWs with two-step TST for LTBI is simple and safe, and hence suitable for wide scale implementation in high

Suspension for the low frequency facility

CERN Document Server

Cella, G; Di Virgilio, A; Gaddi, A; Viceré, A

2000-01-01

We introduce the working principles of the VIRGO Low Frequency Facility (LFF), whose main aim is the measurement of the thermal noise in the VIRGO suspension system. We evaluate the displacement thermal noise of a mirror, which is an intermediate element of a double pendulum suspension system. This double pendulum will be suspended to the last stage of a VIRGO Super-Attenuator (SA), the prototype VIRGO suspension system being tested at the Pisa section of INFN. In the proposed configuration, we evaluate the spectrum of the thermal noise for different choices of the parameters: based on this study, we comment on the future directions to be undertaken in the LFF experiment.

Quenching Combustible Dust Mixtures Using Electric Particulate Suspensions (EPS): A New Testing Method For Microgravity

Science.gov (United States)

Colver, Gerald M.; Greene, Nathanael; Shoemaker, David; Xu, Hua

2003-01-01

The Electric Particulate Suspension (EPS) is a combustion ignition system being developed at Iowa State University for evaluating quenching effects of powders in microgravity (quenching distance, ignition energy, flammability limits). Because of the high cloud uniformity possible and its simplicity, the EPS method has potential for "benchmark" design of quenching flames that would provide NASA and the scientific community with a new fire standard. Microgravity is expected to increase suspension uniformity even further and extend combustion testing to higher concentrations (rich fuel limit) than is possible at normal gravity. Two new combustion parameters are being investigated with this new method: (1) the particle velocity distribution and (2) particle-oxidant slip velocity. Both walls and (inert) particles can be tested as quenching media. The EPS method supports combustion modeling by providing accurate measurement of flame-quenching distance as a parameter in laminar flame theory as it closely relates to characteristic flame thickness and flame structure. Because of its design simplicity, EPS is suitable for testing on the International Space Station (ISS). Laser scans showing stratification effects at 1-g have been studied for different materials, aluminum, glass, and copper. PTV/PIV and a leak hole sampling rig give particle velocity distribution with particle slip velocity evaluated using LDA. Sample quenching and ignition energy curves are given for aluminum powder. Testing is planned for the KC-135 and NASA s two second drop tower. Only 1-g ground-based data have been reported to date.

Effect of Pregnancy on Interferon Gamma Release Assay and Tuberculin Skin Test Detection of Latent TB Infection Among HIV-Infected Women in a High Burden Setting.

Science.gov (United States)

LaCourse, Sylvia M; Cranmer, Lisa M; Matemo, Daniel; Kinuthia, John; Richardson, Barbra A; Horne, David J; John-Stewart, Grace

2017-05-01

Peripartum immunologic changes may affect latent tuberculosis infection (LTBI) diagnostic performance among HIV-infected women. HIV-infected women were serially tested with tuberculin skin test (TST) and interferon gamma release assay [QuantiFERON TB Gold In-tube (QFT)] in pregnancy and 6 weeks postpartum in Kenya. Prevalence, sensitivity and agreement, and correlates of QFT/TST positivity were assessed. Quantitative QFT mitogen and Mycobacterium tuberculosis antigen (Mtb-Ag) responses were compared by peripartum stage. Incidence of test conversion at 6 weeks postpartum was evaluated in baseline TST-/QFT- women. Among 100 HIV-infected women, median age was 26 years, median CD4 was 555 cells per cubic millimeter, and 88% were on antiretrovirals. More women were QFT+ than TST+ in both pregnancy (35.4% vs. 13.5%, P = 0.001) and postpartum (29.6% vs. 14.8%, P pregnancy vs. postpartum, and specifically among persistently QFT+ women (Mtb-Ag: 3.46 vs. 4.48 IU/mL, P = 0.007). QFT indeterminate rate was higher in pregnancy (16%) compared with postpartum (0%) because of lower mitogen response. QFT identified >2-fold more women with LTBI compared with TST in pregnancy and postpartum. Lower QFT Mtb-Ag and mitogen responses in pregnancy compared with postpartum suggest that pregnancy-associated immunologic changes may influence LTBI test performance.

Tuning a Le Mans Car Suspension in ADAMS

CSIR Research Space (South Africa)

Berman, R

2012-09-01

Full Text Available An ADAMS model of South Africa’s first ever Le Mans car was developed and used to tune the suspension parameters. Validation of the model is to be done by comparing simulation results to those obtained in track testing. The suspension parameters...

Differential role of AMPA receptors in mouse tests of antidepressant and anxiolytic action

DEFF Research Database (Denmark)

Andreasen, Jesper T; Fitzpatrick, Ciaran M; Larsen, Maria

2015-01-01

and memory we also tested if GYKI-53655 disrupted performance in the V-maze test for attention-dependent behaviour, and the social transmission of food preference (STFP) test of long-term memory. LY451646 (3 mg/kg) showed an antidepressant-like profile in the FST and TST, and GYKI-53655 (≥ 5 mg/kg) had......-like effect in the FST (≥ 10 mg/kg), but not TST, an anxiolytic-like effect in the EZM (≥ 3 mg/kg) and MB test (≥ 2.5 mg/kg), and an anxiogenic-like effect in the NIH test (≥ 30 mg/kg). GYKI-53655 did not affect cognitive performance in the V-maze or STFP tests. Collectively, these findings suggest...

Operational Modal Analysis and the Performance Assessment of Vehicle Suspension Systems

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L. Soria

2012-01-01

Full Text Available Comfort, road holding and safety of passenger cars are mainly influenced by an appropriate design of suspension systems. Improvements of the dynamic behaviour can be achieved by implementing semi-active or active suspension systems. In these cases, the correct design of a well-performing suspension control strategy is of fundamental importance to obtain satisfying results. Operational Modal Analysis allows the experimental structural identification in those that are the real operating conditions: Moving from output-only data, leading to modal models linearised around the more interesting working points and, in the case of controlled systems, providing the needed information for the optimal design and verification of the controller performance. All these characters are needed for the experimental assessment of vehicle suspension systems. In the paper two suspension architectures are considered equipping the same car type. The former is a semi-active commercial system, the latter a novel prototypic active system. For the assessment of suspension performance, two different kinds of tests have been considered, proving ground tests on different road profiles and laboratory four poster rig tests. By OMA-processing the signals acquired in the different testing conditions and by comparing the results, it is shown how this tool can be effectively utilised to verify the operation and the performance of those systems, by only carrying out a simple, cost-effective road test.

Hybrid superconducting magnetic suspensions

International Nuclear Information System (INIS)

Tixador, P.; Hiebel, P.; Brunet, Y.; Chaud, X.; Gautier-Picard, P.

1996-01-01

Superconductors, especially high T c ones, are the most attractive materials to design stable and fully passive magnetic suspensions which have to control five degrees of freedom. The hybrid superconducting magnetic suspensions present high performances and a simple cooling mode. They consist of a permanent magnet bearing, stabilized by a suitable magnet-superconductor structure. Several designs are given and compared in terms of forces and stiffnesses. The design of the magnet bearing plays an important part. The superconducting magnetic bearing participates less in levitation but must provide a high stabilizing stiffness. This is achieved by the magnet configuration, a good material in term of critical current density and field cooling. A hybrid superconducting suspension for a flywheel is presented. This system consists of a magnet thrust bearing stabilized by superconductors interacting with an alternating polarity magnet structure. First tests and results are reported. Superconducting materials are magnetically melt-textured YBaCuO

Involvement of AMPA receptors in the antidepressant-like effects of dextromethorphan in mice.

Science.gov (United States)

Nguyen, Linda; Matsumoto, Rae R

2015-12-15

Dextromethorphan (DM) is an antitussive with rapid acting antidepressant potential based on pharmacodynamic similarities to ketamine. Building upon our previous finding that DM produces antidepressant-like effects in the mouse forced swim test (FST), the present study aimed to establish the antidepressant-like actions of DM in the tail suspension test (TST), another well-established model predictive of antidepressant efficacy. Additionally, using the TST and FST, we investigated the role of α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) receptors in the antidepressant-like properties of DM because accumulating evidence suggests that AMPA receptors play an important role in the pathophysiology of depression and may contribute to the efficacy of antidepressant medications, including that of ketamine. We found that DM displays antidepressant-like effects in the TST similar to the conventional and fast acting antidepressants characterized by imipramine and ketamine, respectively. Moreover, decreasing the first-pass metabolism of DM by concomitant administration of quinidine (CYP2D6 inhibitor) potentiated antidepressant-like actions, implying DM itself has antidepressant efficacy. Finally, in both the TST and FST, pretreatment with the AMPA receptor antagonist NBQX (2,3-dioxo-6-nitro-1,2,3,4-tetrahydrobenzo[f]quinoxaline-7-sulfonamide) significantly attenuated the antidepressant-like behavior elicited by DM. Together, the data show that DM exerts antidepressant-like actions through AMPA receptors, further suggesting DM may act as a safe and effective fast acting antidepressant drug. Copyright © 2015 Elsevier B.V. All rights reserved.

Tuberculin skin testing and treatment modulates interferon-gamma release assay results for latent tuberculosis in migrants.

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Matthew K O'Shea

Full Text Available Identifying latent tuberculosis infection (LTBI in people migrating from TB endemic regions to low incidence countries is an important control measure. However, no prospective longitudinal comparisons between diagnostic tests used in such migrant populations are available.To compare commercial interferon (IFN-gamma release assays (IGRAs and the tuberculin skin test (TST for diagnosing LTBI in a migrant population, and the influence of antecedent TST and LTBI treatment on IGRA performance.This cohort study, performed from February to September 2012, assessed longitudinal IGRA and TST responses in Nepalese military recruits recently arrived in the UK. Concomitant T-SPOT.TB, QFT-GIT and TST were performed on day 0, with IGRAs repeated 7 and 200 days later, following treatment for LTBI if necessary.166 Nepalese recruits were prospectively assessed. At entry, 21 individuals were positive by T-SPOT.TB and 8 individuals by QFT-GIT. There was substantial agreement between TST and T-SPOT.TB positives at baseline (71.4% agreement; κ = 0.62; 95% CI:0.44-0.79, but only moderate concordance between positive IGRAs (38.1% agreement; κ = 0.46; 95% CI:0.25-0.67. When reassessed 7 days following TST, numbers of IGRA-positive individuals changed from 8 to 23 for QFT-GIT (p = 0.0074 and from 21 to 23 for T-SPOT.TB (p = 0.87. This resulted in an increase in IGRA concordance to substantial (64.3% agreement; κ = 0.73; 95% CI:0.58-0.88. Thus, in total on day 0 and day 7 after testing, 29 out of 166 participants (17.5% provided a positive IGRA and of these 13 were TST negative. Two hundred days after the study commenced and three months after treatment for LTBI was completed by those who were given chemoprophylaxis, 23 and 21 participants were positive by T-SPOT.TB or QFT-GIT respectively. When individual responses were examined longitudinally within this population 35% of the day 7 QFT-GIT-positive, and 19% T-SPOT.TB-positive individuals, were

Installation with magnetic suspension of test bodies for measurement of small forces. Verification of equivalence of inertial and gravitational mass

International Nuclear Information System (INIS)

Kalebin, S.M.

1988-01-01

Torsion installation with magnetic suspension of test bodies for detection of small forces is considered. Installation application for verification of equivalence of inertial and gravitational mass in the case of test body incidence on the Earth (Etvesh experiment) and in the case of their incidene on the Sun (Dicke experiment) is discussed. The total mass of test bodies, produced in the form of cylinders with 3 cm radius, equals 50 kg (one lead body and one copper body); beam radius of test bodies equals 3 cm (the cylinders are tight against one another); ferrite cylinder with 3 cm radius and 10 cm height is used for their suspension in magnetic field. Effect of thermal noise and electromagnetic force disturbances on measurement results is considered. Conducted calculations show that suggested installation enables to improve the accuracy of verifying mentioned equivalence at least by one order and upwards. This suggests that such installation is a matter of interest for experiments on small force detection

Tuberculin Skin Test and Quantiferon in BCG Vaccinated, Immunosuppressed Patients with Moderate-to-Severe Inflammatory Bowel Disease.

Science.gov (United States)

Kurti, Zsuzsanna; Lovasz, Barbara Dorottya; Gecse, Krisztina Barbara; Balint, Anita; Farkas, Klaudia; Morocza-Szabo, Agnes; Gyurcsanyi, Andras; Kristof, Katalin; Vegh, Zsuzsanna; Gonczi, Lorant; Kiss, Lajos Sandor; Golovics, Petra Anna; Lakatos, Laszlo; Molnar, Tamas; Lakatos, Peter Laszlo

2015-12-01

There are few data available on the effect of immunomodulator/biological therapy on the accuracy of the tuberculin skin test (TST) and interferon-gamma release assay (IGRA) in BCG-vaccinated immunosuppressed patients with inflammatory bowel disease (IBD). Our aim was to define the accuracy, predictors and agreement of TST and IGRA in a BCG-vaccinated immunosuppressed referral IBD cohort. 166 consecutive moderate-to-severe IBD patients (122 Crohn's disease, CD and 44 ulcerative colitis, UC) were enrolled in a prospective study from three centers. Patients were treated with immunosuppressives and/or biologicals. IGRA and TST were performed on the same day. Both in- and outpatient records were collected and comprehensively reviewed. TST positivity rate was 23.5%, 21.1%,14.5% and 13.9% when cut-off values of 5, 10, 15 and 20mm were used. IGRA positivity rate was 8.4% with indeterminate result in 0.6%. Chest X-ray was suggestive of latent tuberculosis in 2 patients. Correlation between TST and IGRA was moderate (kappa: 0.39-0.41, p15mm) should be considered to identify patients at risk for latent TB. Accuracy is satisfactory in BCG-vaccinated, immunosuppressed IBD patients. Smoking is a risk factor for TST positivity.

Automation of an interferon-γ release assay and comparison to the tuberculin skin test for screening basic military trainees for Mycobacterium tuberculosis infection.

Science.gov (United States)

Goodwin, Donald J; Mazurek, Gerald H; Campbell, Brandon H; Bohanon, Jamaria; West, Kevin B; Bell, James J; Powell, Richard; Toney, Sean; Morris, John A; Yamane, Grover K; Sjoberg, Paul A

2014-03-01

We automated portions of the QuantiFERON-TB Gold In-Tube test (QFT-GIT) and assessed its quality when performed concurrently with the tuberculin skin test (TST) among U.S. Air Force basic military trainees (BMTs). The volume of blood collected for QFT-GIT was monitored. At least one of the three tubes required for QFT-GIT had blood volume outside the recommended 0.8- to 1.2-mL range for 688 (29.0%) of 2,373 subjects who had their blood collected. Of the 2,124 subjects who had TST and QFT-GIT completed, TST was positive for 0.6%; QFT-GIT was positive for 0.3% and indeterminate for 2.0%. Among 2,081 subjects with completed TST and determinate QFT-GIT results, overall agreement was 99.5% but positive agreement was 5.6%. Specificity among the 1,546 low-risk BMTs was identical (99.7%). Indeterminate QFT-GIT results were 2.7 times more likely when mitogen tubes contained >1.2 mL blood than when containing 0.8- to 1.2-mL blood. Automation can facilitate QFT-GIT completion, especially if the recommended volume of blood is collected. Mycobacterium tuberculosis infection prevalence among BMTs based on TST and QFT-GIT is similar and low. Selectively testing those with significant risk may be more appropriate than universal testing of all recruits. Reprint & Copyright © 2014 Association of Military Surgeons of the U.S.

The antidepressant-like effect of Mentha spicata essential oil in animal models of depression in male mice

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Behnam Jedi-Behnia

2017-06-01

Full Text Available Background & Objective: Previous researches have revealed analgesic and sedative properties of Mentha spicata (MS. The aim of present study was to evaluate the antidepressant effects of MS essential oil in forced swim test (FST and tail suspension test (TST in male mice. Materials & Methods: In this experimental study, 84 male mice were randomly divided into 14 groups of 6: Negative control groups received normal saline (10 ml/kg,i.p., positive control groups received fluoxetine (20mg/kg, i.p. and imipramine (30mg/kg and treatment groups received MS essential oil (30, 60,120 and 240 mg/kg i.p.. In FST, immobility time, swimming time and climbing time and immobility time in TST were recorded in six minutes. Results: Findings indicated that essential oil at doses of 120 and 240 mg/kg, fluoxetine and imipramine reduced immobility time compared to control group in FST and TST (p0.05. In contrast, imipramine increased climbing time without any significant change in swimming time (p>0.05. Conclusion: Based on the findings of the present study, MS essential oil has antidepressant-like activity similar to fluoxetine and probably their compounds (especially carvone with serotonergic mechanism induced their effect. However, further studies are needed to determine the precise mechanism of its action.

Antidepressant-Like Effects of Shuyusan in Rats Exposed to Chronic Stress: Effects on Hypothalamic-Pituitary-Adrenal Function

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Liping Chen

2012-01-01

Full Text Available This study was to investigate antidepressant activities of Shuyusan (a Chinese herb, using a rats model of depression induced by unpredictable chronic mild stress (UCMS. The administration groups were treated with Shuyusan decoction for 3 weeks and compared with fluoxetine treatment. In order to understand the potential antidepressant-like activities of Shuyusan, tail suspension test (TST and forced swimming test (FST were used as behavioral despair study. The level of corticotropin-releasing factor (CRH, adrenocorticotropic hormone (ACTH, corticosterone (CORT and hippocampus glucocorticoid receptor expression were examined. After modeling, there was a significant prolongation of immobility time in administration groups with the TST and FST. High-dose Shuyusan could reduce the immobility time measured with the TST and FST. The immobility time in high-dose herbs group and fluoxetine group was increased significantly compared with the model group. After 3 weeks herbs fed, the serum contents level of CRH, ACTH, and CORT in high-dose herb group was significantly decreased compared to the model group. The result indicated that Shuyusan had antidepressant activity effects on UCMS model rats. The potential antidepressant effect may be related to decreasing glucocorticoid levels activity, regulating the function of HPA axis, and inhibiting glucocorticoid receptor expression in hippocampus.

Antidepressant Potentials of Components from Trichilia monadelpha (Thonn. J.J. de Wilde in Murine Models

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Kennedy Kwami Edem Kukuia

2018-01-01

Full Text Available Trichilia monadelpha is a common medicinal plant used traditionally in treating central nervous system conditions such as epilepsy, depression, pain, and psychosis. In this study, the antidepressant-like effect of crude extracts of the stem bark of T. monadelpha was investigated using two classical murine models, forced swimming test (FST and tail suspension test (TST. The extracts, petroleum ether, ethyl acetate, and hydroethanolic extracts (30–300 mg/kg, p.o., standard drug (imipramine; fluoxetine, 3–30 mg/kg, p.o., and saline (vehicle were given to mice one hour prior to the acute study. In a separate experiment the components (flavonoids, saponins, alkaloids, tannins, and terpenoids; 30–300 mg/kg, p.o. from the most efficacious extract fraction were screened to ascertain which components possessed the antidepressant effect. All the extracts and components significantly induced a decline in immobility in the FST and TST, indicative of an antidepressant-like activity. The extracts and some components showed increase in swimming and climbing in the FST as well as a significant enhancement in swinging and/or curling scores in the TST, suggesting a possible involvement of monoaminergic and/or opioidergic activity. This study reveals the antidepressant-like potential of the stem bark extracts and components of T. monadelpha.

Evaluating damping elements for two-stage suspension vehicles

Directory of Open Access Journals (Sweden)

Ronald M. Martinod R.

2012-01-01

Full Text Available The technical state of the damping elements for a vehicle having two-stage suspension was evaluated by using numerical models based on the multi-body system theory; a set of virtual tests used the eigenproblem mathematical method. A test was developed based on experimental modal analysis (EMA applied to a physical system as the basis for validating the numerical models. The study focused on evaluating vehicle dynamics to determine the influence of the dampers’ technical state in each suspension state.

Design of a New Integrated Structure of the Active Suspension System and Emergency Lane Change Test

Science.gov (United States)

Zhao, Jing-bo; Liu, Hai-mei; Zhang, Lan-chun; Bei, Shao-yi

2017-09-01

An integrated structure of the active suspension system was proposed in order to solve the problem of the individual control of the height of the body or the adjustable damping of the active suspension system of the electric vehicle, which improve the vibration reduction performance of the vehicle. The air bag was used to replace the traditional spiral spring, and the traditional shock absorber was replaced by the damping adjustable shock absorber, and the control module received the body acceleration sensor and the horizontal height sensor signal. The system controlled adjustable damping coefficient of shock absorber through the height of the car body the output of the air pump relay and the height control valve and the output of the electromagnetic valve of the adjustable damping shock absorber, and the emergency lane change test was carried out under different modes of speed of 60km/h. The experimental results indicated that the damping value was greater, average roll angle, yaw angle and average vehicle lateral acceleration were small when vehicle body was in the state of emergency lane change, which verified the feasibility of the integrated control strategy and structure design of the active suspension system. The research has important theoretical research value and engineering application prospect for designing and controlling strategy of vehicle chassis integrated control system.

Licofelone Attenuates LPS-induced Depressive-like Behavior in Mice: A Possible Role for Nitric Oxide.

Science.gov (United States)

Mousavi, Seyyedeh Elaheh; Saberi, Pegah; Ghasemkhani, Naeemeh; Fakhraei, Nahid; Mokhtari, Rezvan; Dehpour, Ahmad Reza

2018-01-01

Licofelone, a dual cyclooxygenase/5-lipoxygenase inhibitor, possesses antioxidant, antiapoptotic, neuroprotective, and anti-inflammatory properties. The aim of the present study was to investigate the effect of licofelone on lipopolysaccharide (LPS)-induced depression in a mouse model and also a possible role for nitric oxide (NO). To elucidate the role of NO on this effect of licofelone (5 and 20 mg/kg, i.p.), L-NAME, a non-specific NO synthase (NOS) inhibitor; aminoguanidine (AG), a specific inducible NOS (iNOS) inhibitor; 7-nitroindazole (7-NI) a preferential neuronal NOS inhibitor (nNOS) and; L-arginine (L-Arg), as a NO donor, were used. The animal's behaviors were evaluated employing forced swimming test (FST), tail suspension test (TST) and open field test (OFT). LPS (0.83 mg/kg, i.p.) induced depressive-like behavior increasing immobility time in FST and TST. Conversely, licofelone (20 mg/kg i.p.) reversed the depressive effect of LPS and lowered the immobility time in FST and TST. On the other hand, pretreatment with L-Arg also reversed the antidepressant-like effect of licofelone (20 mg/kg) in FST and TST. On the other hand, L-NAME (10 and 30 mg/kg), AG (50 and 100 mg/kg) and 7-NI (60 mg/kg) could potentiate licofelone (5 mg/kg) and lowered the immobility duration. NO down-regulation possibly through iNOS and nNOS inhibition may involve in the antidepressant property of licofelone. This article is open to POST-PUBLICATION REVIEW. Registered readers (see "For Readers") may comment by clicking on ABSTRACT on the issue's contents page.

Vibration control of an energy regenerative seat suspension with variable external resistance

Science.gov (United States)

Ning, Donghong; Sun, Shuaishuai; Du, Haiping; Li, Weihua; Zhang, Nong

2018-06-01

In this paper, an energy regenerative seat suspension with a variable external resistance is proposed and built, and a semi-active controller for its vibration control is also designed and validated. The energy regenerative seat suspension is built with a three-phase generator and a gear reducer, which are installed in the scissors structure centre of the seat suspension, and the vibration energy is directly harvested from the rotary movement of suspension's scissors structure. The electromagnetic torque of the semi-active seat suspension actuator is controlled by an external variable resistor. An integrated model including the seat suspension's kinematics and the generator is built and proven to match the test result very well. A simplified experimental phenomenon model is also built based on the test results for the controller design. A state feedback H∞ controller is proposed for the regenerative seat suspension's semi-active vibration control. The proposed regenerative seat suspension and its controller are validated with both simulations and experiments. A well-tuned passive seat suspension is applied to evaluate the regenerative seat's performance. Based on ISO 2631-1, the frequency-weighted root mean square (FW-RMS) acceleration of the proposed seat suspension has a 22.84% reduction when compared with the passive one, which indicates the improvement of ride comfort. At the same time, the generated RMS power is 1.21 W. The proposed regenerative seat suspension can greatly improve the driver's ride comfort and has the potential to be developed to a self-powered semi-active system.

Degradability of aged aquatic suspensions of C60 nanoparticles

DEFF Research Database (Denmark)

Hartmann, Nanna Isabella Bloch; Buendia, Inmaculada M.; Bak, Jimmy

2011-01-01

In this study, aged aqueous suspensions of C(60) (nC(60)) were investigated in the respirometric OECD test for ready biodegradability. Two suspensions of nC(60) were prepared by stirring and aged under indirect exposure to sunlight for 36 months. ATR-FTIR analyses confirmed the presence of C(60)-...

Naratriptan hydrochloride in extemporaneosly compounded oral suspensions.

Science.gov (United States)

Zhang, Y P; Trissel, L A; Fox, J L

2000-01-01

The purpose of this study was to determine the pharmaceutical acceptability and chemical stability of naratriptan hydrochloride in three extemporaneously compounded suspension formulations. The naratriptan-hydrochloride oral suspensions were prepared from 2.5-mg commercial tablets yielding a nominal naratriptan concentration of 0.5 mg/mL. The suspension vehicles selected for testing were Syrpalta, an equal-parts mixture of Ora-Plus and Ora-Sweet, and an equal-parts mixture of Ora-Plus and Ora-Sweet SF. The tablets were crushed and thoroughly triturated to a fine powder using a porcelain mortar and pestle. The powder was incorporated into a portion of the Syrpalta or Ora-Plus suspension vehicle and mixed until homogeneous. The mixtures were then brought to volume with Syrpalta, Ora-Sweet or Ora-Sweet SF, as appropriate. The suspensions were packaged in amber, plastic, screw-cap prescription bottles and stored at 23 deg C for seven days and 4 deg C for 90 days. An adequate suspension was never achieved in Syrpalta. The crushed-tablet powder did not produce a uniformly dispersed mixture and exhibited clumping and a high rate of sedimentation. A distinct layer of the solid tablet material settled immediately after shaking. Over the next four hours, a densely packed, yellow, caked layer formed at the bottom of the containers, making resuspension difficult. During storage, the caking became worse. Chemical analysis was not performed. The Ora-Plus and Ora-Sweet or Ora-Sweet SF suspensions had a slight greenish cast and were resuspended without difficulty by shaking for approximately ten seconds, yielding easily poured and homogeneous mixtures throughout the study. Visible settling and layering did not begin for four hours with the Ora-Sweet suspension and 24 hours for the Ora-Sweet SF suspension. High pressure liquid chromatographic analysis found that the naratriptan concentration in both suspension-vehicle combinations exhibited little or no loss for seven days at 23

Analysis of the Kinematics and Compliance of a Passive Suspension System using Adams Car

Directory of Open Access Journals (Sweden)

N. Ikhsan

2015-06-01

Full Text Available The experimental approach is usually used as the way to develop or modify a suspension system to obtain maximum ride comfort and handling characteristics. This approach is a time-consuming process, costly, and may not guarantee the optimum solution. Thus, to avoid this, a virtual vehicle suspension system is necessary. In this paper, a half-car body of an actual suspension system based on the PROTON WRM 44 P0-34 was modeled and simulated. In total, 10 components comprised each front McPherson strut and rear multilink suspension consisting of different joint types and a number of degrees of freedom. The model was developed by defining the location of the hard point or coordinate before specifying the component characteristics and joint type. The completed suspension model was simulated using the vertical parallel and vertical oppose movement test, the same tests conducted with the actual experimental parameter setup. The kinematics and compliance (K&C of the simulation is compared with the experimental data to verify the suspension model. The outcome from the simulation showed a verified virtual suspension system model with a very minimum percentage of error and different characteristics of the static performance of the suspension system when subjected to the test as explained further in the paper.

Influence of pH and media composition on suspension stability of silver, zinc oxide, and titanium dioxide nanoparticles and immobilization of Daphnia magna under guideline testing conditions.

Science.gov (United States)

Cupi, Denisa; Hartmann, Nanna B; Baun, Anders

2016-05-01

In aquatic toxicity testing of engineered nanoparticles (ENPs) the process of agglomeration is very important as it may alter bioavailability and toxicity. In the present study, we aimed to identify test conditions that are favorable for maintaining stable ENP suspensions. We evaluated the influence of key environmental parameters: pH (2-12) and ionic strength using M7, Soft EPA (S EPA) medium, and Very Soft EPA (VS EPA) medium; and observed the influence of these parameters on zeta potential, zeta average, and acute immobilization of Daphnia magna for three different ENPs. Despite being sterically stabilized, test suspensions of silver (Ag) ENPs formed large agglomerates in both VS EPA and M7 media; and toxicity was found to be higher in VS EPA medium due to increased dissolution. Low-agglomerate suspensions for zinc oxide (ZnO) could be obtained at pH 7 in VS EPA medium, but the increase in dissolution caused higher toxicity than in M7 medium. Titanium dioxide (TiO2) ENPs had a point of zero charge in the range of pH 7-8. At pH 7 in VS EPA, agglomerates with smaller hydrodynamic diameters (~200nm) were present compared to the high ionic strength M7 medium where hydrodynamic diameters reached micrometer range. The stable suspensions of TiO2 ENPs caused immobilization of D. magna, 48-h EC50 value of 13.7mgL(-1) (95% CI, 2.4mg-79.1mgL(-1)); whereas no toxicity was seen in the unstable, highly agglomerated M7 medium suspensions, 48-h EC50 >100mgL(-1). The current study provides a preliminary approach for methodology in testing and assessing stability and toxicity of ENPs in aquatic toxicity tests of regulatory relevance. Copyright © 2016 Elsevier Inc. All rights reserved.

Combustion Aerosols from Full-Scale Suspension-Firing of Wood Pellets

DEFF Research Database (Denmark)

Damø, Anne Juul; Wu, Hao; Frandsen, Flemming

2012-01-01

The objectives of the present work were to investigate the aerosol formation mechanisms during full-scale suspension firing of wood, and, to evaluate the effect of coal fly ash addition on the formation of aerosols under different ash load conditions. Tests with suspension firing of 100 % wood...

The improvement of suspension training for trunk muscle power in Sanda athletes

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Xiujie Ma

2017-12-01

Full Text Available The aim of this study was to investigate whether both suspension training (ST and traditional training (TT can improve Sanda athlete's strength quality of trunk muscles and to explore the effect of suspension training on Sanda athletes' trunk muscle power production. Twelve elite Sanda athletes from the Competitive Sports School of Shanghai University of Sport were randomly assigned to experimental group (EG and control group (CG. EG and CG were regularly trained with suspension training and traditional strength training for 40 minutes three times per week. The total duration of training was 10 weeks. The measurements including peak torque (PT, PT/body weight (BW, and rate of force development (RFD were used to assess trunk muscles strength. The results showed that there were significant differences between the two groups' performance when it was tested at the higher velocity of dynamometer (test of muscle power, but less significant differences when the two groups performance was tested at the lower velocity of dynamometer (test of maximum strength. The conclusion of this study is that compared with traditional training methods, suspension training can improve back and trunk flexion muscles strength more effectively. In particular, suspension training can improve the explosive power of trunk extension and flexion muscles.

Non-linear dielectric spectroscopy of microbiological suspensions

Science.gov (United States)

Treo, Ernesto F; Felice, Carmelo J

2009-01-01

Background Non-linear dielectric spectroscopy (NLDS) of microorganism was characterized by the generation of harmonics in the polarization current when a microorganism suspension was exposed to a sinusoidal electric field. The biological nonlinear response initially described was not well verified by other authors and the results were susceptible to ambiguous interpretation. In this paper NLDS was performed to yeast suspension in tripolar and tetrapolar configuration with a recently developed analyzer. Methods Tripolar analysis was carried out by applying sinusoidal voltages up to 1 V at the electrode interface. Tetrapolar analysis was carried on with sinusoidal field strengths from 0.1 V cm-1 to 70 V cm-1. Both analyses were performed within a frequency range from 1 Hz through 100 Hz. The harmonic amplitudes were Fourier-analyzed and expressed in dB. The third harmonic, as reported previously, was investigated. Statistical analysis (ANOVA) was used to test the effect of inhibitor an activator of the plasma membrane enzyme in the measured response. Results No significant non-linearities were observed in tetrapolar analysis, and no observable changes occurred when inhibitor and activator were added to the suspension. Statistical analysis confirmed these results. When a pure sinus voltage was applied to an electrode-yeast suspension interface, variations higher than 25 dB for the 3rd harmonic were observed. Variation higher than 20 dB in the 3rd harmonics has also been found when adding an inhibitor or activator of the membrane-bounded enzymes. These variations did not occur when the suspension was boiled. Discussion The lack of result in tetrapolar cells suggest that there is no, if any, harmonic generation in microbiological bulk suspension. The non-linear response observed was originated in the electrode-electrolyte interface. The frequency and voltage windows observed in previous tetrapolar analysis were repeated in the tripolar measurements, but maximum were not

Non-linear dielectric spectroscopy of microbiological suspensions

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Felice Carmelo J

2009-09-01

Full Text Available Abstract Background Non-linear dielectric spectroscopy (NLDS of microorganism was characterized by the generation of harmonics in the polarization current when a microorganism suspension was exposed to a sinusoidal electric field. The biological nonlinear response initially described was not well verified by other authors and the results were susceptible to ambiguous interpretation. In this paper NLDS was performed to yeast suspension in tripolar and tetrapolar configuration with a recently developed analyzer. Methods Tripolar analysis was carried out by applying sinusoidal voltages up to 1 V at the electrode interface. Tetrapolar analysis was carried on with sinusoidal field strengths from 0.1 V cm-1 to 70 V cm-1. Both analyses were performed within a frequency range from 1 Hz through 100 Hz. The harmonic amplitudes were Fourier-analyzed and expressed in dB. The third harmonic, as reported previously, was investigated. Statistical analysis (ANOVA was used to test the effect of inhibitor an activator of the plasma membrane enzyme in the measured response. Results No significant non-linearities were observed in tetrapolar analysis, and no observable changes occurred when inhibitor and activator were added to the suspension. Statistical analysis confirmed these results. When a pure sinus voltage was applied to an electrode-yeast suspension interface, variations higher than 25 dB for the 3rd harmonic were observed. Variation higher than 20 dB in the 3rd harmonics has also been found when adding an inhibitor or activator of the membrane-bounded enzymes. These variations did not occur when the suspension was boiled. Discussion The lack of result in tetrapolar cells suggest that there is no, if any, harmonic generation in microbiological bulk suspension. The non-linear response observed was originated in the electrode-electrolyte interface. The frequency and voltage windows observed in previous tetrapolar analysis were repeated in the tripolar

Effects of South African traditional medicine in animal models for depression

DEFF Research Database (Denmark)

Pedersen, Mikael Egebjerg; Szewczyk, Bernadeta; Stachowicz, Katarzyna

2008-01-01

in models for depression. MATERIALS AND METHODS: The extracts were screened for affinity for the serotonin transporter (SERT) in the [(3)H]-citalopram-binding assay. The inhibitory potency of the extracts towards the SERT, the noradrenalin transporter (NAT) and the dopamine transporter (DAT) were determined...... in a functional uptake inhibition assay. Antidepressant-like effects of the extracts were investigated using the tail suspension test (TST) and the forced swim test in both rats (rFST) and mice (mFST). RESULTS: All four plants showed affinity for SERT in the binding assay. AC and BD showed functional inhibition...

Update on quadruple suspension design for Advanced LIGO

International Nuclear Information System (INIS)

Aston, S M; Carbone, L; Cutler, R M; Hoyland, D; Barton, M A; Bland, B; Bell, A S; Beveridge, N; Cagnoli, G; Cantley, C A; Cumming, A V; Cunningham, L; Hammond, G D; Haughian, K; Hough, J; Brummitt, A J; Greenhalgh, R J S; Hayler, T M; Heptonstall, A; Heefner, J

2012-01-01

We describe the design of the suspension systems for the major optics for Advanced LIGO, the upgrade to LIGO—the Laser Interferometric Gravitational-Wave Observatory. The design is based on that used in GEO600—the German/UK interferometric gravitational wave detector, with further development to meet the more stringent noise requirements for Advanced LIGO. The test mass suspensions consist of a four-stage or quadruple pendulum for enhanced seismic isolation. To minimize suspension thermal noise, the final stage consists of a silica mirror, 40 kg in mass, suspended from another silica mass by four silica fibres welded to silica ears attached to the sides of the masses using hydroxide-catalysis bonding. The design is chosen to achieve a displacement noise level for each of the seismic and thermal noise contributions of 10 −19 m/√Hz at 10 Hz, for each test mass. We discuss features of the design which has been developed as a result of experience with prototypes and associated investigations. (paper)

Weakly sheared active suspensions: hydrodynamics, stability, and rheology.

Science.gov (United States)

Cui, Zhenlu

2011-03-01

We present a kinetic model for flowing active suspensions and analyze the behavior of a suspension subjected to a weak steady shear. Asymptotic solutions are sought in Deborah number expansions. At the leading order, we explore the steady states and perform their stability analysis. We predict the rheology of active systems including an activity thickening or thinning behavior of the apparent viscosity and a negative apparent viscosity depending on the particle type, flow alignment, and the anchoring conditions, which can be tested on bacterial suspensions. We find remarkable dualities that show that flow-aligning rodlike contractile (extensile) particles are dynamically and rheologically equivalent to flow-aligning discoid extensile (contractile) particles for both tangential and homeotropic anchoring conditions. Another key prediction of this work is the role of the concentration of active suspensions in controlling the rheological behavior: the apparent viscosity may decrease with the increase of the concentration.

Antidepressant-like effect of aqueous extract of Channa striatus fillet in mice models of depression.

Science.gov (United States)

Saleem, A M; Taufik Hidayat, M; Mat Jais, A M; Fakurazi, S; Moklas, Mohamad; Sulaiman, M R; Amom, Z

2011-07-01

Channa (C.) striatus (Malay-Haruan), is a fresh water snakehead fish, consumed as a rejuvenating diet in post-parturition period in local Malay population. The aqueous extract of C. striatus fillet (AECSF) was reported to act through serotonergic receptor system in a previous study. There is no scientific report on neuropharmacological effects of C. striatus. Based on these data, the antidepressant-like effect of C. striatus was evaluated in mice models of depression. AECSF was prepared by steaming the fillets as described previously. Antidepressant activity was studied in male ICR mice using forced swimming test (FST) and tail suspension test (TST). Open-field test was used to evaluate any psychomotor stimulant activity. AECSF was administered intraperitoneally at the concentrations of 30%, 40% and 50% w/v at the dosage of 10 ml/kg. Amitriptyline (10 mg/kg) was used as positive control. All the three concentrations of AECSF (30%, 40% and 50% w/v) significantly reduced the immobility time (p open-field test. AECSF produced significant reduction of immobility time in both FST and TST. Amitriptyline produced a significant reduction of immobility time in both FST and TST similar to previous findings. The AECSF produced a dose-dependent decrease in locomotor activity in the open-field test. This hypolocomotion effect indicated the absence of any psychomotor stimulant activity thereby supporting the antidepressant-like effect of the AECSF. The pharmacological mechanisms of the observed antidepressant-like effect and hypolocomotion effect are not understood from our study. Hence, further studies are required.

Influence of pH and media composition on suspension stability of silver, zinc oxide, and titanium dioxide nanoparticles and immobilization of Daphnia magna under guideline testing conditions

DEFF Research Database (Denmark)

Cupi, Denisa; Hartmann, Nanna B.; Baun, Anders

2016-01-01

sterically stabilized, test suspensions of silver (Ag) ENPs formed large agglomerates in both VS EPA and M7 media; and toxicity was found to be higher in VS EPA medium due to increased dissolution. Low-agglomerate suspensions for zinc oxide (ZnO) could be obtained at pH 7 in VS EPA medium, but the increase...

Non-linear Characteristic Modeling of Frictional Suspension Using Measured Data

Energy Technology Data Exchange (ETDEWEB)

Yoon, Chang Gyu; Jang, Jin Seok; Jin, Jae Hoon; Yoo, Wan Suk [Pusan National University, Busan (Korea, Republic of)

2015-01-15

Large-capacity of household washing machine can become unbalanced during the dehydration process. To solve this problem, several types of suspensions have been installed in a washing machine. In this study, physical tests were carried out on a frictional suspension, and the nonlinear characteristics were modeled by combining several simple physical models. The parameters were estimated based on the least squares solution. The simulation and test results were compared to verify the validity of the friction damper model.

Comparison of Tuberculin Skin Test result and interferon gamma response to human PPD in BCG scar positive and negative children.

Science.gov (United States)

Sayyahfar, Shirin; Karimi, Abdollah; Fahimzad, Alireza; Shamshiri, Ahmad Reza

2014-03-01

The aim of this study is to compare Tuberculin Skin Test (TST) result and interferon gamma response to human PPD (purified protein derivative), in scar positive and scar negative BCG-vaccinated children. Between August 2007 and May 2008 a total of 236 children aged 1-168 months (mean 21 months) admitted to Mofid Children's Hospital, Tehran, Iran, were enrolled in a cross-sectional study. Each patient was examined for BCG vaccine scar and tested with TST and human PPD-based Interferon Gamma Release Assay (IGRA). Two hundred and twenty one cases out of 236 (44% female, 1-168 months, mean age 21 months) were scar positive of whom 95% TST result was negative. Human PPD-based IGRA was positive in 110 (49.8%), negative in 85 (38.4 %) and indeterminate in 26 (11.8%) of scar positive patients. Fifteen children (40% female, 1-156 months; mean age 42 months) were scar negative. All the scar negative cases were TST negative. Human PPD-based IGRA was positive in 10 (66.7%), negative in 4 (26.7%) and indeterminate in 1 (6.7%) of scar negative patients. Immune responsiveness to human PPD antigens in scar positive and negative children may not correspond with results of the Tuberculin Skin Test. Copyright © 2013 Ministry of Health, Saudi Arabia. Published by Elsevier Ltd. All rights reserved.

The effect of visual and musical suspense on brain activation and memory during naturalistic viewing.

Science.gov (United States)

Bezdek, Matthew A; Wenzel, William G; Schumacher, Eric H

2017-10-01

We tested the hypothesis that, during naturalistic viewing, moments of increasing narrative suspense narrow the scope of attentional focus. We also tested how changes in the emotional congruency of the music would affect brain responses to suspense, as well as subsequent memory for narrative events. In our study, participants viewed suspenseful film excerpts while brain activation was measured with functional magnetic resonance imaging. Results indicated that suspense produced a pattern of activation consistent with the attention-narrowing hypothesis. For example, we observed decreased activation in the anterior calcarine sulcus, which processes the visual periphery, and increased activity in nodes of the ventral attention network and decreased activity in nodes of the default mode network. Memory recall was more accurate for high suspense than low suspense moments, but did not differ by soundtrack congruency. These findings provide neural evidence that perceptual, attentional, and memory processes respond to suspense on a moment-by-moment basis. Copyright © 2017 Elsevier B.V. All rights reserved.

Hydropneumatic suspension systems

Energy Technology Data Exchange (ETDEWEB)

Bauer, Wolfgang

2011-07-01

Hydropneumatic suspensions systems combine the excellent properties of gas springs with the favourable damping properties of hydraulic fluids. The advantages of these systems are particularly appropriate for automotive applications, such as passenger cars, trucks and agricultural equipment. In this book, Dr. Bauer provides an extensive overview of hydropneumatic suspension systems. Starting with a comparison of different types of suspension systems, the author subsequently describes the theoretical background associated with spring and damping characteristics of hydropneumatic systems and furthermore explains the design of the most important system components. Additionally he gives an overview of level control systems and various special functions. Finally the technology is illustrated by design examples and the outlook for future hydropneumatic suspensions is discussed. (orig.)

Dopamine mediated antidepressant effect of Mucuna pruriens seeds in various experimental models of depression.

Science.gov (United States)

Rana, Digvijay G; Galani, Varsha J

2014-01-01

The effects of antidepressant treatments have traditionally been discussed primarily in terms of effects on noradrenergic and serotonergic systems. Multiple lines of investigation have also explored the role of dopaminergic systems in mental depression. Seed of Mucuna pruriens Linn. (DC) (Leguminoseae) is well-known with dopaminergic action and has several therapeutic applications in folk medicine in curing or managing a wide range of diseases including Parkinsonism. To elucidate the anti-depressent profile and possible dopaminergic modulating action of M. pruriens seeds in various experimental models of depression. In the present study, antidepressant effect of the hydroalcoholic extract of the M. pruriens seeds (MPE) (100 and 200 mg/kg, p.o.) was investigated in the Forced Swimming Test (FST), Tail Suspension Test (TST), and Chronic Unpredictable Mild Stress (CUMS) test in mice. Further, dopaminergic interaction of same doses of MPE in the FST and TST were checked by the administration of a haloperidol (0.1 mg/kg, i.p.) and bromocriptine (2 mg/kg, i.p.) on the 7(th) day of MPE treatment. Effect of MPE on locomotor activity was also checked using actophotometer. MPE produced a significant reduction of the immobility time in the FST and TST. Further, antidepressant action of MPE was significantly inhibited by haloperidol and potentiated by bromocriptine in the FST and TST. 21 days of MPE treatment produced protection in CUMS as indicated by a significant increase of sucrose intake of stressed mice. Locomotor activities of mice were not significantly changed after 1 h and 7(th) day of the MPE treatment. The results of this study indicate that hydroalcoholic extract of MPE have antidepressant action, which may be mediated by an interaction with the dopaminergic system.

Particle interactions in concentrated suspensions

International Nuclear Information System (INIS)

Mondy, L.A.; Graham, A.L.; Abbott, J.R.; Brenner, H.

1993-01-01

An overview is presented of research that focuses on slow flows of suspensions in which colloidal and inertial effects are negligibly small. The authors describe nuclear magnetic resonance imaging experiments to quantitatively measure particle migration occurring in concentrated suspensions undergoing a flow with a nonuniform shear rate. These experiments address the issue of how the flow field affects the microstructure of suspensions. In order to understand the local viscosity in a suspension with such a flow-induced, spatially varying concentration, one must know how the viscosity of a homogeneous suspension depends on such variables as solids concentration and particle orientation. The authors suggest the technique of falling ball viscometry, using small balls, as a method to determine the effective viscosity of a suspension without affecting the original microstructure significantly. They also describe data from experiments in which the detailed fluctuations of a falling ball's velocity indicate the noncontinuum nature of the suspension and may lead to more insights into the effects of suspension microstructure on macroscopic properties. Finally, they briefly describe other experiments that can be performed in quiescent suspensions (in contrast to the use of conventional shear rotational viscometers) in order to learn more about boundary effects in concentrated suspensions

Self-powered suspension criterion and energy regeneration implementation scheme of motor-driven active suspension

Science.gov (United States)

Yan, Shuai; Sun, Weichao

2017-09-01

Active suspension systems have advantages on mitigating the effects of vehicle vibration caused by road roughness, which are one of the most important component parts in influencing the performances of vehicles. However, high amount of energy consumption restricts the application of active suspension systems. From the point of energy saving, this paper presents a self-powered criterion of the active suspension system to judge whether a motor-driven suspension can be self-powered or not, and then a motor parameter condition is developed as a reference to design a self-powered suspension. An energy regeneration implementation scheme is subsequently proposed to make the active suspension which has the potential to be self-powered achieve energy-saving target in the real application. In this implementation scheme, operating electric circuits are designed based on different working status of the actuator and power source and it is realizable to accumulate energy from road vibration and supply energy to the actuator by switching corresponding electric circuits. To apply the self-powered suspension criterion and energy regeneration implementation scheme, an active suspension system is designed with a constrained H∞ controller and calculation results indicate that it has the capability to be self-powered. Simulation results show that the performances of the self-powered active suspension are nearly the same as those of the active suspension with an external energy source and can achieve energy regeneration at the same time.

Predictive factors for repetition of the tuberculin test after a nonreactive test in patients with HIV/AIDS Factores predictivos para la repetición de la prueba de la tuberculina después de un resultado no reactivo en pacientes con infección por el VIH/sida

Directory of Open Access Journals (Sweden)

Líbia Cristina Rocha Vilela Moura

2012-02-01

Full Text Available OBJECTIVE: The outcome of interest was repetition of the tuberculin skin test (TST and the objectives were to estimate the rate of TST repetition, the probability of no TST repetition after 1 year, and the probability of no TST repetition at the end of the follow-up period in patients whose initial test was nonreactive. The study also set out to analyze factors associated with the time until TST repetition at two HIV/AIDS referral services that carry out the TST on a routine basis in Recife, Pernambuco, Brazil. METHODS: A cohort of HIV-positive patients who initially tested nonreactive on the TST were followed from November 2007 to February 2010. The Kaplan-Meier method was used to estimate the probability of not repeating the TST, and Cox's regression analysis was used to analyze the factors associated with time until repeating the TST. Cox's multivariate analysis was stratified according to each hospital where patients were followed, because this variable did not respect the principle of proportionality of risk. RESULTS: The probability of not repeating the TST for 1 year was 80.0% and at the end of the follow-up period it was 42.0%. The variables that remained associated with TST repetition in the final Cox multivariate model were an age of 40 years or older, body mass index between 18.0 and 24.9, being female, and years of schooling. CONCLUSIONS: This study encountered a very low TST repetition rate after 1 year of follow-up and identified groups of individuals who should be the target of interventions aimed at repeating the TST.OBJETIVO: El resultado principal de interés fue la repetición de la prueba de la tuberculina (PT y los objetivos fueron calcular la tasa de repetición de la PT, la probabilidad de no repetir la PT después de un año y la probabilidad de no repetir la PT al final del período de seguimiento en los pacientes cuya prueba inicial fue no reactiva. En el estudio también se analizaron los factores asociados con el

Simple additive manufacturing of an osteoconductive ceramic using suspension melt extrusion

DEFF Research Database (Denmark)

Slots, Casper; Bonde Jensen, Martin; Ditzel, Nicholas

2017-01-01

/calcium phosphate suspension melt for simple additive manufacturing of ceramic tricalcium phosphate implants. METHODS: A wide variety of non-aqueous liquids were tested to determine the formulation of a storable 3D printable tricalcium phosphate suspension ink, and only fatty acid-based inks were found to work...

Gastrointestinal tract wall visualization and distention during abdominal and pelvic multidetector CT with a neutral barium sulphate suspension: comparison with positive barium sulphate suspension and with water.

Science.gov (United States)

Oliva, M R; Erturk, S M; Ichikawa, T; Rocha, T; Ros, P R; Silverman, S G; Mortele, K J

2012-01-01

When examining patients with contrast-enhanced multidetector-row CT, we determined if the stomach and small bowel were visualized and distended better with a neutral barium sulphate suspension than with positive barium sulphate suspension or water. After obtaining approval from our institutional review board, 156 patients (women: 84; mean age: 54 yrs) with no history of gastrointestinal tract disease were randomized prospectively to receive orally either 900 ml of neutral (0.1% w/v) barium sulphate suspension (n = 53), 900 ml of positive (2.1% w/v) barium sulphate suspension (n = 53), or 900 ml of water (n = 50), prior to undergoing contrast-enhanced abdominal and pelvic multidetector-row CT. Two independent radiologists evaluated the stomach, and small bowel, for luminal distension and wall visualization, using a five point scale. Results were compared using Kruskal-Wallis and Mann-Whitney U tests. The walls of the stomach, and small bowel were visualized better in patients who were administered neutral barium sulphate suspension than those who were administered either positive barium sulphate suspension (p barium sulphate suspension, the stomach and small bowel were distended better compared to patients administered water (p barium sulphate suspension (p contrast-enhanced abdominal and pelvic multidetector-row CT, orally administered neutral barium sulphate suspension allows the gastrointestinal tract to be visualized and distended better than either positive barium sulphate suspension, or water.

Quantiferon test for tuberculosis screening in sarcoidosis patients

DEFF Research Database (Denmark)

Milman, Nils; Søborg, Bolette; Svendsen, Claus Bo

2011-01-01

Tumour necrosis factor-alpha (TNF-α) inhibitors have been introduced in the treatment of refractory sarcoidosis. These biologics may reactivate latent tuberculosis infection (LTBI). Despite its known limitations, the tuberculin skin test (TST) is currently used for the diagnosis of LTBI in Danish...

The feasibility of the interferon gamma release assay and predictors of discordance with the tuberculin skin test for the diagnosis of latent tuberculosis infection in a remote Aboriginal community.

Directory of Open Access Journals (Sweden)

Gonzalo G Alvarez

Full Text Available The tuberculin skin test (TST is the standard test used to screen for latent TB infection (LTBI in the northern Canadian territory of Nunavut. Interferon gamma release assays (IGRA are T cell blood-based assays to diagnose LTBI. The Bacillus Calmette-Guerin (BCG vaccine is part of the routine immunization schedule in Nunavut. The objective of this study was to test the feasibility, and predictors of discordance between the Tuberculin Skin Test (TST and the IGRA assay in a medically under-serviced remote arctic Aboriginal population.Both the TST and QuantiFERON-TB Gold (Qiagen group IGRA tests were offered to people in their homes as part of a public health campaign aimed at high TB risk residential areas in Iqaluit, Nunavut, Canada. Feasibility was measured by the capacity of the staff to do the test successfully as measured by the proportion of results obtained.In this population of predominantly young Inuit who were mostly BCG vaccinated, the use of IGRA for the diagnosis of LTBI was feasible. IGRA testing resulted in more available test results reaching patients (95.6% vs 90.9% p = 0.02 but took longer (median 8 days (IGRA vs 2 days (TST, p value < 0.0001. 44/256 participants (17.2% had discordant results. Multivariable regression analysis suggested that discordant results were most likely to have received multiple BCG vaccinations (RR 20.03, 95% CI, 3.94-101.82, followed by BCG given post infancy (RR 8.13, 95% CI, 2.54-26.03 and then to a lesser degree when BCG was given in infancy (RR 6.43, 95% CI, 1.72-24.85.IGRA is feasible in Iqaluit, Nunavut, a remote Arctic community. IGRA testing results in more test results available to patients compared to TST. This test could result in fewer patients requiring latent TB treatment among those previously vaccinated with BCG in a region with limited public health human resources.

Stability of allopurinol and of five antineoplastics in suspension.

Science.gov (United States)

Dressman, J B; Poust, R I

1983-04-01

The stability of allopurinol, azathioprine, chlorambucil, melphalan, mercaptopurine, and thioguanine each in an extemporaneously prepared suspension was studied. Tablets of each drug were crushed, mixed with a suspending agent, and brought to a final volume of 10, 15, or 20 ml with a 2:1 mixture of simple syrup and wild cherry syrup. Suspensions were prepared in the following concentrations: allopurinol (20 mg/ml), azathioprine (50 mg/ml), chlorambucil (2 mg/ml), melphalan (2 mg/ml), mercaptopurine (50 mg/ml), and thioguanine (40 mg/ml). Using high-performance liquid chromatography or ultraviolet scans, duplicate assays were performed on each suspension periodically during storage for up to 84 days at ambient room temperature or 5 degrees C. The time required for the suspensions to drop below 90% of labeled strength was used as an indicator of drug stability. Allopurinol and azathioprine were stable for at least 56 days at room temperature and at 5 degrees C. Chlorambucil decomposed rapidly at room temperature but was stable for seven days when stored at 5 degrees C. Melphalan suspensions did not meet the stated criteria for stability even at the time of initial assay. Mercaptopurine and thioguanine were stable for 14 and 84 days, respectively, at room temperature; at 5 degrees C, assay values dropped below those obtained at room temperature. In the suspension formulation tested, allopurinol, azathioprine, mercaptopurine, and thioguanine are stable for at least 14 days at room temperature; chlorambucil suspensions should be refrigerated and discarded after seven days. Melphalan decomposes too rapidly to make this suspension formulation feasible for extemporaneous compounding.

Anomalous intrinsic viscosity of octadecylamine-functionalised carbon nanotubes in suspension.

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Donovan, K J; Scott, K

2013-06-28

Single walled carbon nanotubes, SWCNTs, are used as a model cylinder of nanoscopic dimensions for testing rheological theories of how addition of cylindrical particles affects the viscosity of a suspension of such particles. Using the rate of growth of the accompanying induced linear dichroism following application of an applied electric field, the dynamics of carbon nanotube alignment is studied in suspensions of octadecylamine functionalised single walled carbon nanotubes, ODA-SWCNTs, in 1,2 dichloroethane. From such measurements the viscosity of the suspension is measured as the concentration of the suspension is varied. While working within the dilute limit the viscosity is found to increase linearly with concentration and the intrinsic viscosity of the suspension is found to be 8000. This anomalously high intrinsic viscosity is compared with the predictions of various models for a rigid cylinder and found to be incompatible with any of the current models. Some suggestions are made as to the way this ODA-SWCNT result may be eventually accommodated within other models.

Revisiting homogeneous suspension reactors for production of radioisotopes

International Nuclear Information System (INIS)

Pasqualini, E.E.

2010-01-01

Some 50 years ago in Geneva Conferences I, II and III (1955. 1958 and 1964) on the Peaceful Uses of Atomic Energy, and also in Vienna Symposium on Reactor Experiments (1961), several papers where presented by different countries referring to advances in homogeneous suspension reactors. In particular the Dutch KEMA Suspension Test Reactor (KSTR) was developed, built and successfully operated in the sixties and seventies. It was a 1MWth reactor in which a suspension (6 microns spheres) of mixed UO 2 /ThO 2 in light water was circulated in a closed loop through a sphere-shaped vessel. One of the basic ideas on these suspension reactors was to apply the fission recoil separation effect as a means of purification of the fuel: the non-volatile fission products can be adsorbed in dispersed active charcoal and removed from the liquid. Undoubtedly, this method can present some advantages and better yields for the production of Mo-99 and other short lived radioisotopes, since they have to be extracted from a liquid in which practically no uranium is present. Details are mentioned of the different aspects that have been taken into account and which ones could be added in the corresponding actualization of suspension reactors for radioisotope production. In recent years great advances have been made in nanotechnology that can be used in the tailoring of fuel particles and adsorbent media. Recently, in CNEA Buenos Aires, a new facility has been inaugurated and is being equipped and licensed for laboratory experiments and preparative synthesis of nuclear nanoparticles. RA-6 and RA-3 experimental reactors in Argentina can be used for in-pile testing. (author)

Thermal Conductivity Analysis and Lifetime Testing of Suspension Plasma-Sprayed Thermal Barrier Coatings

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Nicholas Curry

2014-08-01

Full Text Available Suspension plasma spraying (SPS has become an interesting method for the production of thermal barrier coatings for gas turbine components. The development of the SPS process has led to structures with segmented vertical cracks or column-like structures that can imitate strain-tolerant air plasma spraying (APS or electron beam physical vapor deposition (EB-PVD coatings. Additionally, SPS coatings can have lower thermal conductivity than EB-PVD coatings, while also being easier to produce. The combination of similar or improved properties with a potential for lower production costs makes SPS of great interest to the gas turbine industry. This study compares a number of SPS thermal barrier coatings (TBCs with vertical cracks or column-like structures with the reference of segmented APS coatings. The primary focus has been on lifetime testing of these new coating systems. Samples were tested in thermo-cyclic fatigue at temperatures of 1100 °C for 1 h cycles. Additional testing was performed to assess thermal shock performance and erosion resistance. Thermal conductivity was also assessed for samples in their as-sprayed state, and the microstructures were investigated using SEM.

The influence of suspension components friction on race car vertical dynamics

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Benini, Claudio; Gadola, Marco; Chindamo, Daniel; Uberti, Stefano; Marchesin, Felipe P.; Barbosa, Roberto S.

2017-03-01

This work analyses the effect of friction in suspension components on a race car vertical dynamics. It is a matter of fact that race cars aim at maximising their performance, focusing the attention mostly on aerodynamics and suspension tuning: suspension vertical and rolling stiffness and damping are parameters to be taken into account for an optimal setup. Furthermore, friction in suspension components must not be ignored. After a test session carried out with a F4 on a Four Poster rig, friction was detected on the front suspension. The real data gathered allow the validation of an analytical model with friction, confirming that its influence is relevant for low frequency values closed to the car pitch natural frequency. Finally, some setup proposals are presented to describe what should be done on actual race cars in order to correct vehicle behaviour when friction occurs.

Paeonol attenuates lipopolysaccharide-induced depressive-like behavior in mice.

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Tao, Weiwei; Wang, Hanqing; Su, Qiang; Chen, Yanyan; Xue, Wenda; Xia, Baomei; Duan, Jinao; Chen, Gang

2016-04-30

The present study was designed to detect the anti-depressant effects of paeonol and the possible mechanisms in the lipopolysaccharide-induced depressive-like behavior. Open-field test(OFT), tail suspension test(TST) and forced swimming test(FST) were used to evaluate the behavioral activity. The contents of 5-hydroxytryptamine (5-HT) and norepinephrine (NE) in mice hippocampus were determined by HPLC-ECD. Serum interleukin (IL)-1β, IL-6 and tumor necrosis factor (TNF)-α levels were evaluated by enzyme-linked immunosorbent assay (ELISA). Our results showed that LPS significantly decreased the levels of 5-HT and NE in the hippocampus. LPS also reduced open-field activity, as well as increased immobility duration in FST and TST. Paeonol administration could effectively reverse the alterations in the concentrations of 5-HT, NE and reduce the IL-6 and TNF-α levels. Moreover, paeonol effectively downregulated brain-derived neurotrophic factor (BDNF), tropomyosin-related kinase B (TrkB) and Nuclear factor-κB (NF-κB) in hippocampal. In conclusion, paeonol administration exhibited significant antidepressant-like effects in mice with LPS-induced depression. Copyright © 2016. Published by Elsevier Ireland Ltd.

Detection of toxic shock toxin (tst gene in Staphylococcus aureus isolated from bovine milk samples

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S. Baniardalan

2017-09-01

Full Text Available Staphylococcus aureus is a major causative pathogen of clinical and subclinical mastitis in dairy cattle all over the world. This agent produces a variety of extracellular toxins and virulence factors in-cluding toxic shock syndrome toxin-1 (TSST-1 which is the major cause of toxic shock syndrome (TSS. In the present study, 76 S. aureus isolates have been obtained from milk samples collected from 7 dairy herds in Hamedan province of Iran. The isolates were identified based on the biochemical and molecular methods using PCR amplification of the femA gene. The staphylococcal isolates were also examined for the presence of TSST-1 (tst encoding gene. This gene was detected in only one S. aureus isolate (1.3%. The results revealed that S. aureus strains causing bovine mastitis may potentially produce staphylococcal toxic shock syndrome toxin-1, indicating that it is very important to follow the presence of TSST-1 producing S. aureus isolates in foodstuffs to protect consumers against the risk of toxic shock syndrome

Investigating high-concentration monoclonal antibody powder suspension in nonaqueous suspension vehicles for subcutaneous injection.

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Bowen, Mayumi; Armstrong, Nick; Maa, Yuh-Fun

2012-12-01

Developing high-concentration monoclonal antibody (mAb) liquid formulations for subcutaneous (s.c.) administration is challenging because increased viscosity makes injection difficult. To overcome this obstacle, we investigated a nonaqueous powder suspension approach. Three IgG1 mAbs were spray dried and suspended at different concentrations in Miglyol® 840, benzyl benzoate, or ethyl lactate. Suspensions were characterized for viscosity, particle size, and syringeability; physical stability was visually inspected. Suspensions generally outperformed liquid solutions for injectability despite higher viscosity at the same mAb concentrations. Powder formulations and properties had little effect on viscosity or injectability. Ethyl lactate suspensions had lowest viscosity (Miglyol® 840 improved overall performance in high mAb concentration suspensions. This study demonstrated the viability of high mAb concentration (>300 mg/mL) in suspension formulations for s.c. administration. Copyright © 2012 Wiley Periodicals, Inc.

Design and test of a novel magnetic lead screw for active suspension system in a vehicle

DEFF Research Database (Denmark)

Berg, Nick Ilsø; Holm, Rasmus Koldborg; Rasmussen, Peter Omand

2014-01-01

. Furthermore the Magnetic Lead Screw is introduced and its benefits when used with an active suspension system are discussed. Based on a model of a quarter car, the design specifications for the MLS active suspension system are found, which leads to a design study. The design study investigates the relation...

Disturbance observer based Takagi-Sugeno fuzzy control for an active seat suspension

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Ning, Donghong; Sun, Shuaishuai; Zhang, Fei; Du, Haiping; Li, Weihua; Zhang, Bangji

2017-09-01

In this paper, a disturbance observer based Takagi-Sugeno (TS) fuzzy controller is proposed for an active seat suspension; both simulations and experiments have been performed verifying the performance enhancement and stability of the proposed controller. The controller incorporates closed-loop feedback control using the measured acceleration of the seat and deflection of the suspension; these two variables can be easily measured in practical applications, thus allowing the proposed controller to be robust and adaptable. A disturbance observer that can estimate the disturbance caused by friction, model simplification, and controller output error has also been used to compensate a H∞ state feedback controller. The TS fuzzy control method is applied to enhance the controller's performance by considering the variation of driver's weight during operation. The vibration of a heavy duty vehicle seat is largest in the frequency range between 2 Hz and 4 Hz, in the vertical direction; therefore, it is reasonable to focus on controlling low frequency vibration amplitudes and maintain the seat suspensions passivity at high frequency. Moreover, both the simulation and experimental results show that the active seat suspension with the proposed controller can effectively isolate unwanted vibration amplitudes below 4.5 Hz, when compared with a well-tuned passive seat suspension. The active controller has been further validated under bump and random road tests with both a 55 kg and a 70 kg loads. The bump road test demonstrated the controller has good transient response capabilities. The random road test result has been presented both in the time domain and the frequency domain. When with the above two loads, the controlled seat suspensions root-mean-square (RMS) accelerations were reduced by 45.5% and 49.5%, respectively, compared with a well-tuned passive seat suspension. The proposed active seat suspension controller has great potential and is very practical for application

Four-Wheel Vehicle Suspension System

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Bickler, Donald B.

1990-01-01

Four-wheel suspension system uses simple system of levers with no compliant components to provide three-point suspension of chassis of vehicle while maintaining four-point contact with uneven terrain. Provides stability against tipping of four-point rectangular base, without rocking contact to which rigid four-wheel frame susceptible. Similar to six-wheel suspension system described in "Articulated Suspension Without Springs" (NPO-17354).

Suspension trauma; Le traumatisme de suspension

Energy Technology Data Exchange (ETDEWEB)

Trudel, S. [Le Centre de sante et de services sociaux du rocher Perce, Chandler, PQ (Canada)

2010-07-01

This presentation discussed the precautions that should be taken to avoid falls from wind turbines or transmission towers. Suspension trauma was explained by a medical doctor in terms of physiology and the body's normal circulation and the elements that disturb normal physiology when in suspension. The trauma occurs following a fall, which carries the risk of 1or more disorders, such as massive hemorrhage, high cardiac pulse, and constriction of blood vessels. Nausea, vertigo, cardiac arrhythmia and sweating occur 15 to 20 minutes following the fall. The presentation emphasized the importance of having qualified personnel at the site and wearing proper harnesses and equipment that supports the neck. figs.

Characterization and stabilization of suspension of bovine bone ash

International Nuclear Information System (INIS)

Carus, L.A.; Bento, L.; Takimi, A.S.; Braganca, S.R.

2012-01-01

The bovine bone powder is the main component in the production of bone china, which is known to be one of the finest and most expensive tableware. This special type of porcelain has unique aesthetic characteristics, among which stands out the whiteness, translucency and brightness. The properties of this porcelain, as well as its manufacture, depend on the characteristics of the bone ash. In this study the rheological properties of the suspensions using exclusively bovine bone ash were evaluated by testing the influence of the concentration of solids in suspension, the calcination temperature and the use of dispersing agents. It was found that the powder calcination temperature affects the rheology of the suspension by lowering the viscosity. (author)

Suspension Hydrogen Reduction of Iron Oxide Concentrates

Energy Technology Data Exchange (ETDEWEB)

H.Y. Sohn

2008-03-31

The objective of the project is to develop a new ironmaking technology based on hydrogen and fine iron oxide concentrates in a suspension reduction process. The ultimate objective of the new technology is to replace the blast furnace and to drastically reduce CO2 emissions in the steel industry. The goals of this phase of development are; the performance of detailed material and energy balances, thermochemical and equilibrium calculations for sulfur and phosphorus impurities, the determination of the complete kinetics of hydrogen reduction and bench-scale testing of the suspension reduction process using a large laboratory flash reactor.

Tuberculin skin testing: Spectrum of adverse reactions.

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Praveen, Ramar; Bahuguna, Amit; Dhadwal, Bhumesh Singh

2015-01-01

Tuberculin skin testing (TST) is one of the primary diagnostic modalities recommended by the World Health Organization (WHO) and the National Institute for Health and Care Excellence (NICE) study conducted in the United Kingdom (UK) for diagnosing tuberculosis (TB). Even after acceptance as a diagnostic modality and stern standardization, TST has its own flaws that include a spectrum of adverse reactions. We report a series of cases with a spectrum of adverse reactions occurring with a higher frequency than present in the available evidence. The study has some demerits such as being a retrospective one with interobserver variation and lack of histopathological confirmation. The observation is presented to accentuate the fact that adverse reactions are not a rarity and that further studies are required to establish the cause and exact incidence of the same.

Latent tuberculosis infection, tuberculin skin test and vitamin D status in contacts of tuberculosis patients: a cross-sectional and case-control study

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Arnedo-Pena Alberto

2011-12-01

Full Text Available Abstract Background Deficient serum vitamin D levels have been associated with incidence of tuberculosis (TB, and latent tuberculosis infection (LTBI. However, to our knowledge, no studies on vitamin D status and tuberculin skin test (TST conversion have been published to date. The aim of this study was to estimate the associations of serum 25-hydroxyvitamin D3 (25[OH]D status with LTBI prevalence and TST conversion in contacts of active TB in Castellon (Spain. Methods The study was designed in two phases: cross-sectional and case-control. From November 2009 to October 2010, contacts of 42 TB patients (36 pulmonary, and 6 extra-pulmonary were studied in order to screen for TB. LTBI and TST conversion cases were defined following TST, clinical, analytic and radiographic examinations. Serum 25(OHD levels were measured by electrochemiluminescence immunoassay (ECLIA on a COBAS® 410 ROCHE® analyzer. Logistic regression models were used in the statistical analysis. Results The study comprised 202 people with a participation rate of 60.1%. Only 20.3% of the participants had a sufficient serum 25(OHD (≥ 30 ng/ml level. In the cross-sectional phase, 50 participants had LTBI and no association between LTBI status and serum 25(OHD was found. After 2 months, 11 out of 93 negative LTBI participants, without primary prophylaxis, presented TST conversion with initial serum 25(OHD levels: a:19.4% (7/36: Conclusions The results suggest that sufficient serum 25(OHD levels protect against TST conversion.

In vitro tests of barium sulphate suspensions for double contrast examinations of the stomach

International Nuclear Information System (INIS)

Treugut, H.; Huebener, K.H.

1980-01-01

Four barium sulphate suspensions were investigated with respect to their adhesion and contrast following standard means of spreading the contrast over a model stomach, which corresponds in its detailed structure with the surface of the gastric mucosa. By this means various factors, which make a true comparison in vivo impossible, could be eliminated and a comparison of the suspensions became possible. Using similar mechanical and chemical situations, the radiographs of the artificial mucosa showed very different results from the use of the different preparations. These corresponded well with the findings in vivo. (orig.) [de

Nested folded-beam suspensions with low longitudinal stiffness for comb-drive actuators

International Nuclear Information System (INIS)

Hou, Max T; Huang, Ming-Xian; Chang, Chao-Min

2014-01-01

Nested folded-beam suspensions with a low longitudinal spring constant and a high lateral spring constant have been used in comb-drive actuators. In the new design, every two flexible beams and two stiff members form a parallelogram flexure, which is considered as an ‘element’ of the nested folded-beam suspension. A set of these flexures of increasing size were placed one outside another to compose a nested structure. In this way, a serial mechanical connection between adjacent parallelogram flexures was formed; thus, a longer output stroke was obtained by combining the stroke displacements of all flexures in an additive fashion. The designed suspensions were theoretically analyzed and numerically simulated. Furthermore, comb-drive actuators with conventional and new suspensions were fabricated and tested to verify the predicted function. In the testing cases, the longitudinal spring constants of suspensions with two (conventional), three and four parallelogram flexures on each side were measured as 2.77, 1.75 and 1.36 N m −1 . The ratio among these three values was approximately 6:4:3, which is consistent with the theoretical predictions and simulation results. Microfabricated folded beams in series were achieved. (paper)

Degradability of aged aquatic suspensions of C60 nanoparticles

DEFF Research Database (Denmark)

Hartmann, B.; Buendia, Inmaculada M.; Baun, Anders

2011-01-01

While studies of the potential human and environmental effects of C60 and its derivatives are emerging in the scientific literature, the environmental fate of C60 is still largely unknown. In this study, aged aqueous suspensions of C60 (nC60) were investigated in the respirometric OECD test...... for ready biodegradability. Two suspensions of nC60 were prepared by stirring and aged under indirect exposure to sunlight for 36 months, which resulted in relatively stable suspensions with a dark-brown colour. The suspended nC60 could not be extracted into toluene and indicating that the particles were...... no longer present as underivatised nC60 but had undergone a transformation. TEM images and particle tracking analysis showed that the suspension consisted of particle aggregates with a size of 156 nm (SD=54nm) and 139nm (Sd=49), respectively, but also contained smaller aggregates. Samples of the nC60...

Evaluating Suspension Formulations of Theophylline Cocrystals With Artificial Sweeteners.

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Aitipamula, Srinivasulu; Wong, Annie B H; Kanaujia, Parijat

2018-02-01

Pharmaceutical cocrystals have garnered significant interest as potential solids to address issues associated with formulation development of drug substances. However, studies concerning the understanding of formulation behavior of cocrystals are still at the nascent stage. We present results of our attempts to evaluate suspension formulations of cocrystals of an antiasthmatic drug, theophylline, with 2 artificial sweeteners. Stability, solubility, drug release, and taste of the suspension formulations were evaluated. Suspension that contained cocrystal with acesulfame showed higher drug release rate, while a cocrystal with saccharin showed a significant reduction in drug release rate. The cocrystal with saccharin was found stable in suspension for over 9 weeks at accelerated test condition; in contrast, the cocrystal with acesulfame was found unstable. Taste analysis using an electronic taste-sensing system revealed improved sweetness of the suspension formulations with cocrystals. Theophylline has a narrow therapeutic index with a short half-life which necessitates frequent dosing. This adversely impacts patient compliance and enhances risk of gastrointestinal and cardiovascular adverse effects. The greater thermodynamic stability, sweetness, and sustained drug release of the suspension formulation of theophylline-saccharin could offer an alternative solution to the short half-life of theophylline and make it a promising formulation for treating asthmatic pediatric and geriatric patients. Copyright © 2018 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

Suspension, a Wake-Up Call: Rural Educators' Attitudes toward Suspension.

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Henderson, Joan; Friedland, Billie

Data from the West Virginia Department of Education reveals that from September 1991 to January 1992, school districts reported 18,915 out-of-school suspensions involving 12,997 students. In 1995, the West Virginia State Legislature enacted the Safe Schools Act, which specifically mandates suspension for no less than 12 consecutive months for…

Determination of Weight Suspension Rigidity in the Transport-Erector Aggregates

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V. A. Zverev

2016-01-01

Full Text Available The aim is to determine weight suspension rigidity in aggregates designed to perform technological transport-erector operations at the miscellaneous launch complexes.We consider the weight suspension comprising the following distinctive structural components: the executive weight-lowering mechanism, polyspast mechanism, rope, traverse, and rods. A created structural dynamic model of suspension allowed us to define weight suspension rigidity. Within the framework of design analysis of a dynamic model we determined the rigidity of its structural units, i.e. traverse, rope, and polyspast.Known analytical relationships were used to calculate the rope rigidity. To determine rigidity of polyspast and traverse have been created special models based on the finite element method. For each model deformation in the specific points under the test load have been defined. Data obtained were used to determine trigidity of traverses and polyspast, and also rigidity of suspension in total. The rigidity models of polispast mechanism and traverse have been developed and calculated using the software complex "Zenit-95".As the research results, the paper presents a dynamic model of the weight suspension of the transport-erector aggregate, the finite element models of the polispast mechanism and traverse, an algorithm for determining the weight suspension rigidity and relevant analytical relationships.Independent calculation of weight suspension rigidity enables us to simplify further dynamic calculation of the aggregate-weight system because it allows attaining a simpler model of the aggregate-weight system that uses the weight suspension model as an element of equivalent rigidity. Despite this simplification the model allows us to determine correctly weight movement parameters and overloads in the aggregate-weight system in the process of technical operations.

Mixing and solid suspension in a stirred precipitator

International Nuclear Information System (INIS)

Chang, T.P.

1986-04-01

Full-scale mixing and solid suspension studies have been conducted to determine the optimum agitator design for precipitators used in plutonium processing. Design considerations include the geometry of precipitator vessels, feed locations, flow patterns, and product requirements. Evaluations of various agitator designs are based on their capabilities: (1) to achieve uniform mixing of reactants in minimum time, (2) to suspend slurry uniformly throughout the vessel, and (3) to minimize power consumption without inducing air entrainment. Tests of full-scale agitator designs showed that significant improvements in mixing, solid suspension, and energy consumption were achieved

Design of a suspension system and determining suspension parameters of a medium downforce small Formula type car

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Biswal Sadjyot

2017-01-01

Full Text Available The focus of the paper is on designing a suspension system for a medium downforce small Formula type race car. The paper not only focusses on step by step design for a double wishbone type suspension but will also show the use and role of kinematics software in determining the optimized suspension of the car. The paper will also focus on the use of tire data in determining suspension parameters and the design of the double wishbone suspension. Various parameters, their design importance and the process to optimize them according to suspension design goals will be covered. The easiest and best ways to change the suspension parameters to get the best results will also be covered.

Stability of an extemporaneously compounded minoxidil oral suspension.

Science.gov (United States)

Song, Yunmei; Chin, Zen Whey; Ellis, David; Lwin, Ei Mon Phyo; Turner, Sean; Williams, Desmond; Garg, Sanjay

2018-03-01

Results of a study to determine the stability of an extemporaneously compounded minoxidil oral suspension under various temperature and stress conditions are reported. Commercially available minoxidil tablets (10 mg) were crushed to a fine powder, and predetermined amounts of 2 suspending vehicles were added to produce a 1-mg/mL suspension, which was stored in glass bottles at room temperature (25 ± 2 °C) or in a refrigerator (4 ± 2 °C). To simulate daily patient use, 5 days weekly 1 bottle of the suspension was removed from refrigerated storage and shaken and 0.5 mL of the contents discarded. At each specified time point, samples were analyzed in duplicate ( n = 6 for each test condition) using a validated high-performance liquid chromatography method. Samples were visually observed and their pH measured at each time point. Microbiological studies were performed on day 0 and at week 24. The mean percentage of initial minoxidil concentration remaining in all refrigerated samples exceeded 90% throughout the 24-week study, with no change in appearance, pH, microbial activity, odor, or redispersibility. During storage at room temperature, the suspension exhibited a color change at week 4, with slight sedimentation after 6 weeks, although minoxidil recovery exceeded 90% for 10 weeks. An extemporaneously compounded minoxidil oral suspension was stable for 24 weeks when stored in a refrigerator. This suspension can be used for up to 3 weeks when stored at room temperature. Copyright © 2018 by the American Society of Health-System Pharmacists, Inc. All rights reserved.

Quenching of Particle-Gas Combustible Mixtures Using Electric Particulate Suspension (EPS) and Dispersion Methods

Science.gov (United States)

Colver, Gerald M.; Goroshin, Samuel; Lee, John H. S.

2001-01-01

A cooperative study is being carried out between Iowa State University and McGill University. The new study concerns wall and particle quenching effects in particle-gas mixtures. The primary objective is to measure and interpret flame quenching distances, flammability limits, and burning velocities in particulate suspensions. A secondary objective is to measure particle slip velocities and particle velocity distribution as these influence flame propagation. Two suspension techniques will be utilized and compared: (1) electric particle suspension/EPS; and (2) flow dispersion. Microgravity tests will permit testing of larger particles and higher and more uniform dust concentrations than is possible in normal gravity.

Effects of transients in LIGO suspensions on searches for gravitational waves.

Science.gov (United States)

Walker, M; Abbott, T D; Aston, S M; González, G; Macleod, D M; McIver, J; Abbott, B P; Abbott, R; Adams, C; Adhikari, R X; Anderson, S B; Ananyeva, A; Appert, S; Arai, K; Ballmer, S W; Barker, D; Barr, B; Barsotti, L; Bartlett, J; Bartos, I; Batch, J C; Bell, A S; Betzwieser, J; Billingsley, G; Birch, J; Biscans, S; Biwer, C; Blair, C D; Bork, R; Brooks, A F; Ciani, G; Clara, F; Countryman, S T; Cowart, M J; Coyne, D C; Cumming, A; Cunningham, L; Danzmann, K; Da Silva Costa, C F; Daw, E J; DeBra, D; DeRosa, R T; DeSalvo, R; Dooley, K L; Doravari, S; Driggers, J C; Dwyer, S E; Effler, A; Etzel, T; Evans, M; Evans, T M; Factourovich, M; Fair, H; Fernández Galiana, A; Fisher, R P; Fritschel, P; Frolov, V V; Fulda, P; Fyffe, M; Giaime, J A; Giardina, K D; Goetz, E; Goetz, R; Gras, S; Gray, C; Grote, H; Gushwa, K E; Gustafson, E K; Gustafson, R; Hall, E D; Hammond, G; Hanks, J; Hanson, J; Hardwick, T; Harry, G M; Heintze, M C; Heptonstall, A W; Hough, J; Izumi, K; Jones, R; Kandhasamy, S; Karki, S; Kasprzack, M; Kaufer, S; Kawabe, K; Kijbunchoo, N; King, E J; King, P J; Kissel, J S; Korth, W Z; Kuehn, G; Landry, M; Lantz, B; Lockerbie, N A; Lormand, M; Lundgren, A P; MacInnis, M; Márka, S; Márka, Z; Markosyan, A S; Maros, E; Martin, I W; Martynov, D V; Mason, K; Massinger, T J; Matichard, F; Mavalvala, N; McCarthy, R; McClelland, D E; McCormick, S; McIntyre, G; Mendell, G; Merilh, E L; Meyers, P M; Miller, J; Mittleman, R; Moreno, G; Mueller, G; Mullavey, A; Munch, J; Nuttall, L K; Oberling, J; Oliver, M; Oppermann, P; Oram, Richard J; O'Reilly, B; Ottaway, D J; Overmier, H; Palamos, J R; Paris, H R; Parker, W; Pele, A; Penn, S; Phelps, M; Pierro, V; Pinto, I; Principe, M; Prokhorov, L G; Puncken, O; Quetschke, V; Quintero, E A; Raab, F J; Radkins, H; Raffai, P; Reid, S; Reitze, D H; Robertson, N A; Rollins, J G; Roma, V J; Romie, J H; Rowan, S; Ryan, K; Sadecki, T; Sanchez, E J; Sandberg, V; Savage, R L; Schofield, R M S; Sellers, D; Shaddock, D A; Shaffer, T J; Shapiro, B; Shawhan, P; Shoemaker, D H; Sigg, D; Slagmolen, B J J; Smith, B; Smith, J R; Sorazu, B; Staley, A; Strain, K A; Tanner, D B; Taylor, R; Thomas, M; Thomas, P; Thorne, K A; Thrane, E; Torrie, C I; Traylor, G; Tuyenbayev, D; Vajente, G; Valdes, G; van Veggel, A A; Vecchio, A; Veitch, P J; Venkateswara, K; Vo, T; Vorvick, C; Ward, R L; Warner, J; Weaver, B; Weiss, R; Weßels, P; Willke, B; Wipf, C C; Worden, J; Wu, G; Yamamoto, H; Yancey, C C; Yu, Hang; Yu, Haocun; Zhang, L; Zucker, M E; Zweizig, J

2017-12-01

This paper presents an analysis of the transient behavior of the Advanced LIGO (Laser Interferometer Gravitational-wave Observatory) suspensions used to seismically isolate the optics. We have characterized the transients in the longitudinal motion of the quadruple suspensions during Advanced LIGO's first observing run. Propagation of transients between stages is consistent with modeled transfer functions, such that transient motion originating at the top of the suspension chain is significantly reduced in amplitude at the test mass. We find that there are transients seen by the longitudinal motion monitors of quadruple suspensions, but they are not significantly correlated with transient motion above the noise floor in the gravitational wave strain data, and therefore do not present a dominant source of background noise in the searches for transient gravitational wave signals. Using the suspension transfer functions, we compared the transients in a week of gravitational wave strain data with transients from a quadruple suspension. Of the strain transients between 10 and 60 Hz, 84% are loud enough that they would have appeared above the sensor noise in the top stage quadruple suspension monitors if they had originated at that stage at the same frequencies. We find no significant temporal correlation with the suspension transients in that stage, so we can rule out suspension motion originating at the top stage as the cause of those transients. However, only 3.2% of the gravitational wave strain transients are loud enough that they would have been seen by the second stage suspension sensors, and none of them are above the sensor noise levels of the penultimate stage. Therefore, we cannot eliminate the possibility of transient noise in the detectors originating in the intermediate stages of the suspension below the sensing noise.

Antidepressant-like effects of nicotinic acetylcholine receptor antagonists, but not agonists, in the mouse forced swim and mouse tail suspension tests

DEFF Research Database (Denmark)

Andreasen T., Jesper; Olsen, G M; Wiborg, O

2009-01-01

Current literature suggests involvement of nicotinic acetylcholine receptors (nAChRs) in major depression. However, it is controversial whether the antidepressant-like effect of nAChR modulation is induced by activation, desensitization or inhibition of central nAChRs. In addition, the specific n......AChR subtype/s involved remains unknown. In this study, we systematically compared the effects of non-selective and selective nicotinic agonists and antagonists in two different tests for antidepressant effects in mice: the tail suspension test and the forced swim test. Compounds: nicotine, RJR-2403 (alpha4...

Design and evaluation of a suspension seat to reduce vibration exposure of subway operators: a case study.

Science.gov (United States)

Marcotte, Pierre; Beaugrand, Sylvie; Boutin, Jérôme; Larue, Christian

2010-01-01

Subway operators have complained about discomfort caused by whole-body vibration. To address this problem, a suspension seat with extensive ergonomic features has been adapted to the confined space of the subway operator cab. The suspension was modified from an existing suspension in order to reduce the dominant frequency of the subway vertical vibration (2.4 Hz). The suspension seat has been extensively tested on a vertical hydraulic shaker. These tests have shown that the SEAT value was lower for a higher vibration level, for higher subject weight, and for the suspension adjusted at median height. The seat also produces a lower SEAT value when there was a predominance of the 6 Hz vibration component. The horizontal seat adjustments had no influence on the suspension SEAT value. Removing the suspension damper also decreases the SEAT value for all the tested configurations. The final version of the suspension seat prototype was validated during normal subway operation with 19 different operators having weight in the 5th, 50th and 95th percentile of the operator population. Accelerations were measured with triaxial accelerometers at the seat cushion, above the suspension and on the floor. In addition to the vibration measurements, each operator was asked about his perceived discomfort from vibration exposure. Globally, the suspension seat attenuated the vertical vibration (SEAT values from 0.86 to 0.99), but discomfort due to amplification of the 2.4 Hz component occurred when the suspension height was adjusted at the minimum, even when the global weighted acceleration was lower (SEAT value < 1). These results suggest that in order to reduce the discomfort caused by whole-body vibration, the transmissibility of the seat should also be considered, in particular when there is a dominant frequency in the vibration spectra.

Effect of suspension kinematic on 14 DOF vehicle model

Science.gov (United States)

Wongpattananukul, T.; Chantharasenawong, C.

2017-12-01

Computer simulations play a major role in shaping modern science and engineering. They reduce time and resource consumption in new studies and designs. Vehicle simulations have been studied extensively to achieve a vehicle model used in minimum lap time solution. Simulation result accuracy depends on the abilities of these models to represent real phenomenon. Vehicles models with 7 degrees of freedom (DOF), 10 DOF and 14 DOF are normally used in optimal control to solve for minimum lap time. However, suspension kinematics are always neglected on these models. Suspension kinematics are defined as wheel movements with respect to the vehicle body. Tire forces are expressed as a function of wheel slip and wheel position. Therefore, the suspension kinematic relation is appended to the 14 DOF vehicle model to investigate its effects on the accuracy of simulate trajectory. Classical 14 DOF vehicle model is chosen as baseline model. Experiment data is collected from formula student style car test runs as baseline data for simulation and comparison between baseline model and model with suspension kinematic. Results show that in a single long turn there is an accumulated trajectory error in baseline model compared to model with suspension kinematic. While in short alternate turns, the trajectory error is much smaller. These results show that suspension kinematic had an effect on the trajectory simulation of vehicle. Which optimal control that use baseline model will result in inaccuracy control scheme.

Use of MBS (ADAMS / CAR software in simulations of vehicle suspension systems

Directory of Open Access Journals (Sweden)

Łukasz KONIECZNY

2014-03-01

Full Text Available The results of the examination of a vehicle suspension system in the plate position are presented in the paper. The model vehicle is a Fiat Seicento with front independent suspension, McPherson type, with the steering system and with the semi-trailing arm in the rear suspension. Identification of the model was made by comparing the simulation results with the results from the test stand. A multibody model of the vehicle will be used in studies of the impact of shock absorber technical conditions on the dynamics of automotive vehicles.

Large-scale photochemical reactions of nanocrystalline suspensions: a promising green chemistry method.

Science.gov (United States)

Veerman, Marcel; Resendiz, Marino J E; Garcia-Garibay, Miguel A

2006-06-08

Photochemical reactions in the solid state can be scaled up from a few milligrams to 10 grams by using colloidal suspensions of a photoactive molecular crystal prepared by the solvent shift method. Pure products are recovered by filtration, and the use of H(2)O as a suspension medium makes this method a very attractive one from a green chemistry perspective. Using the photodecarbonylation of dicumyl ketone (DCK) as a test system, we show that reaction efficiencies in colloidal suspensions rival those observed in solution. [reaction: see text

Tuberculin skin test and interferon-gamma release assay values are associated with antimicrobial peptides expression in  polymorphonuclear cells during latent tuberculous infection

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Julio E Castañeda-Delgado

2014-06-01

Full Text Available It has been reported that patients with progressive tuberculosis (TB express abundant amounts of the antimicrobial peptides (AMPs cathelicidin (LL-37 and human neutrophil peptide-1 (HNP-1 in circulating cells, whereas latent TB infected donors showed no differences when compared with purified protein derivative (PPD and QuantiFERON®-TB Gold (QFT-healthy individuals. The aim of this study was to determine whether LL-37 and HNP-1 production correlates with higher tuberculin skin test (TST and QFT values in TB household contacts. Twenty-six TB household contact individuals between 26-58 years old TST and QFT positive with at last two years of latent TB infection were recruited. AMPs production by polymorphonuclear cells was determined by flow cytometry and correlation between TST and QFT values was analysed. Our results showed that there is a positive correlation between levels of HNP-1 and LL-37 production with reactivity to TST and/or QFT levels. This preliminary study suggests the potential use of the expression levels of these peptides as biomarkers for progression in latent infected individuals.

One-Quarter-Car Active SuspensionModel Verification

Directory of Open Access Journals (Sweden)

Hyniova Katerina

2017-01-01

Full Text Available Suspension system influences both the comfort and safety of the passengers. In the paper, energy recuperation and management in automotive suspension systems with linear electric motors that are controlled by a designed H∞ controller to generate a variable mechanical force for a car damper is presented. Vehicle shock absorbers in which forces are generated in response to feedback signals by active elements obviously offer increased design flexibility compared to the conventional suspensions with passive elements (springs and dampers. The main advantage of the proposed solution that uses a linear AC motor is the possibility to generate desired forces acting between the unsprung (wheel and sprung (one-quarter of the car body mass masses of the car, providing good insulation of the car sprung mass from the road surface roughness and load disturbances. As shown in the paper, under certain circumstances linear motors as actuators enable to transform mechanical energy of the vertical car vibrations to electrical energy, accumulate it, and use it when needed. Energy flow control enables to reduce or even eliminate the demands on the external power source. In particular, the paper is focused on experiments with active shock absorber that has been taken on the designed test bed and the way we developed an appropriate input signal for the test bed that as real road disturbance acts upon the vibration absorber and the obtained results are evaluated at the end. Another important point the active suspension design should satisfy is energy supply control that is made via standard controller modification, and which allows changing amount of energy required by the system. Functionality of the designed controller modification was verified taking various experiments on the experiment stand as mentioned in the paper.

The Syndrome Burnout as Deterioration of Work Environment and the TST Position of the Use of the Principles And Concepts Environmental

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Erica Fabiola Brito Tuma

2015-12-01

Full Text Available This paper will address the applicability of environmental principles in cases of syndrome of "burnout". For this, it will analyze the concepts of general environment and its categories, highlighting the working environment in which the characteristics of its healthiness will be appointed. They will be treated also the concepts of degradation of environmental quality and pollution, and how they occur in the middle working environment, emphasizing the protection of quality of life and health of workers. So relate the "burnout" syndrome as the middle work environment degradation factor, and discussed the consequences of this framework. Finally, recent decisions will be presented the Superior Labor Court (TST about this psychological pathology.

Constraint Embedding for Vehicle Suspension Dynamics

Directory of Open Access Journals (Sweden)

Jain Abhinandan

2016-06-01

Full Text Available The goal of this research is to achieve close to real-time dynamics performance for allowing auto-pilot in-the-loop testing of unmanned ground vehicles (UGV for urban as well as off-road scenarios. The overall vehicle dynamics performance is governed by the multibody dynamics model for the vehicle, the wheel/terrain interaction dynamics and the onboard control system. The topic of this paper is the development of computationally efficient and accurate dynamics model for ground vehicles with complex suspension dynamics. A challenge is that typical vehicle suspensions involve closed-chain loops which require expensive DAE integration techniques. In this paper, we illustrate the use the alternative constraint embedding technique to reduce the cost and improve the accuracy of the dynamics model for the vehicle.

Synthesis and Evaluation of New 1,5-Diaryl-3-[4-(methyl-sulfonylphenyl]-4,5-dihydro-1H-pyrazole Derivatives as Potential Antidepressant Agents

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Ahmet Özdemir

2015-02-01

Full Text Available In an effort to develop potent antidepressant agents, new pyrazoline derivatives 2a–s were synthesized and evaluated for their antidepressant-like activity by tail suspension test (TST and modified forced swimming test (MFST. The effects of the compounds on spontaneous locomotor activity were also investigated using an activity cage apparatus. Among these derivatives, compounds 2b, 2d, 2f, 2o, and 2r decreased both horizontal and vertical activity number of the mice. On the other hand, compounds 2a, 2h, 2j, 2k, 2l, 2m, and 2n, which did not induce any significant change in the locomotor activity, significantly shortened the immobility time of mice in TST and MFST, representing the presence of the antidepressant-like effect. Additionally, the same compounds increased the swimming time of mice in MFST without any change in climbing duration, similar to the reference drug fluoxetine (10 mg/kg. In the light of previous papers examining the effects of pyrazolines on central nervous system, this study, once more, pointed out remarkable antidepressant activity potential of pyrazoline derivatives.

Inertia Wheel on Low-Noise Active Magnetic Suspension

Science.gov (United States)

Carabelli, S.; Genta, G.; Silvagni, M.; Tonoli, A.

2002-01-01

Magnetic bearings are particularly suited for space applications for a number of reasons: - they are ideally suited for vacuum applications; - the lack of lubrication and wear enhances the reliability and guaranties a long maintenance-free operation - the low drag torque decreases power consumption and reduces the torque exerted on the stator of the machine. - the possibility of insulating actively the spacecraft from the excitation due to unbalance of the rotating system In the case of reaction wheels, a well designed magnetic suspension allows high speed operation with a very low power consumption and vibration level. Conversely, microgravity (and possibly vacuum) operation is an advantage for magnetic bearings. The absence of static forces allows to operate with low current levels, thus reducing electrical noise and allowing to reach even lower vibration levels than in Earth applications of magnetic bearings. Active magnetic bearings (AMB) allow to adapt the working characteristics of the system to the operating needs: it is possible to use the actuators to lock the system during launch (absence of grabbers) and to stiffen the suspension when the spacecraft is accelerated (impulsive phases), while working in conditions optimised for microgravity when this is needed. Magnetic suspension systems designed for microgravity environment cannot be correctly tested on the ground. Testing in ground conditions results in the need of grossly overdesigning the levitation device; furthermore, in some cases ground testing is completely impossible, if not by introducing devices which compensate for the Earth gravitational field. If the compensation for the gravitational force is supplied by the same actuators used for microgravity operation, the actuators and the power amplifiers must be overdesigned and in some cases the suspension can be altogether impossible. They work in conditions which are much different from nominal ones and, above all, it is impossible to reach the

Neural control of magnetic suspension systems

Science.gov (United States)

Gray, W. Steven

1993-01-01

The purpose of this research program is to design, build and test (in cooperation with NASA personnel from the NASA Langley Research Center) neural controllers for two different small air-gap magnetic suspension systems. The general objective of the program is to study neural network architectures for the purpose of control in an experimental setting and to demonstrate the feasibility of the concept. The specific objectives of the research program are: (1) to demonstrate through simulation and experimentation the feasibility of using neural controllers to stabilize a nonlinear magnetic suspension system; (2) to investigate through simulation and experimentation the performance of neural controllers designs under various types of parametric and nonparametric uncertainty; (3) to investigate through simulation and experimentation various types of neural architectures for real-time control with respect to performance and complexity; and (4) to benchmark in an experimental setting the performance of neural controllers against other types of existing linear and nonlinear compensator designs. To date, the first one-dimensional, small air-gap magnetic suspension system has been built, tested and delivered to the NASA Langley Research Center. The device is currently being stabilized with a digital linear phase-lead controller. The neural controller hardware is under construction. Two different neural network paradigms are under consideration, one based on hidden layer feedforward networks trained via back propagation and one based on using Gaussian radial basis functions trained by analytical methods related to stability conditions. Some advanced nonlinear control algorithms using feedback linearization and sliding mode control are in simulation studies.

High-impact exercise in rats prior to and during suspension can prevent bone loss

International Nuclear Information System (INIS)

Yanagihara, G.R.; Paiva, A.G.; Gasparini, G.A.; Macedo, A.P.; Frighetto, P.D.; Volpon, J.B.; Shimano, A.C.

2016-01-01

High-impact exercise has been considered an important method for treating bone loss in osteopenic experimental models. In this study, we investigated the effects of osteopenia caused by inactivity in femora and tibiae of rats subjected to jump training using the rat tail suspension model. Eight-week-old female Wistar rats were divided into five groups (n=10 each group): jump training for 2 weeks before suspension and training during 3 weeks of suspension; jump training for 2 weeks before suspension; jump training only during suspension; suspension without any training; and a control group. The exercise protocol consisted of 20 jumps/day, 5 days/week, with a jump height of 40 cm. The bone mineral density of the femora and tibiae was measured by double energy X-ray absorptiometry and the same bones were evaluated by mechanical tests. Bone microarchitecture was evaluated by scanning electron microscopy. One-way ANOVA was used to compare groups. Significance was determined as P<0.05. Regarding bone mineral density, mechanical properties and bone microarchitecture, the beneficial effects were greater in the bones of animals subjected to pre-suspension training and subsequently to training during suspension, compared with the bones of animals subjected to pre-suspension training or to training during suspension. Our results indicate that a period of high impact exercise prior to tail suspension in rats can prevent the installation of osteopenia if there is also training during the tail suspension

High-impact exercise in rats prior to and during suspension can prevent bone loss

Energy Technology Data Exchange (ETDEWEB)

Yanagihara, G.R.; Paiva, A.G.; Gasparini, G.A.; Macedo, A.P. [Laboratório de Bioengenharia, Departamento de Biomecânica, Medicina e Reabilitação do Aparelho Locomotor, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP (Brazil); Frighetto, P.D. [Instituto Federal de Educação, Ciência e Tecnologia de São Paulo, São Paulo, SP (Brazil); Volpon, J.B.; Shimano, A.C. [Laboratório de Bioengenharia, Departamento de Biomecânica, Medicina e Reabilitação do Aparelho Locomotor, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP (Brazil)

2016-02-02

High-impact exercise has been considered an important method for treating bone loss in osteopenic experimental models. In this study, we investigated the effects of osteopenia caused by inactivity in femora and tibiae of rats subjected to jump training using the rat tail suspension model. Eight-week-old female Wistar rats were divided into five groups (n=10 each group): jump training for 2 weeks before suspension and training during 3 weeks of suspension; jump training for 2 weeks before suspension; jump training only during suspension; suspension without any training; and a control group. The exercise protocol consisted of 20 jumps/day, 5 days/week, with a jump height of 40 cm. The bone mineral density of the femora and tibiae was measured by double energy X-ray absorptiometry and the same bones were evaluated by mechanical tests. Bone microarchitecture was evaluated by scanning electron microscopy. One-way ANOVA was used to compare groups. Significance was determined as P<0.05. Regarding bone mineral density, mechanical properties and bone microarchitecture, the beneficial effects were greater in the bones of animals subjected to pre-suspension training and subsequently to training during suspension, compared with the bones of animals subjected to pre-suspension training or to training during suspension. Our results indicate that a period of high impact exercise prior to tail suspension in rats can prevent the installation of osteopenia if there is also training during the tail suspension.

An observational study of the effect of vibration on the caking of suspensions in oily vehicles.

Science.gov (United States)

Jain, Rohit; Bork, Olaf; Alawi, Fadil; Nanjan, Karthigeyan; Tucker, Ian G

2016-11-30

An oily suspension of penethamate (PNT) that was physically stable on storage, caked solidly during road/air transport. This paper reports on the caking behaviour of PNT oily suspension formulations exposed to vibrations in a lab-based test designed to simulate road/air transport. The lab-test was used to study the effects of container type (glass v PET) and formulation (oil, surfactant type and concentration) on the physical stability of suspension under vibration. Redispersibility of the sediment was lower at longer vibrations times and at higher intensity of vibration. Caking on vibration was strongly influenced by the type of container (caking in glass but not in PET) possibly due to tribo-charging of particles. Caking on vibration was dependent on the formulation: type and concentration of surfactant; type of oil. The physical stability of oily suspensions, and the effect of vibration are two areas which have been largely neglected in the pharmaceutical literature. This paper discusses some potential mechanisms for the observations but studies using fully characterised materials are required. Finally we conclude that static testing of physical stability of oily suspensions is not sufficient and that a vibrational stress test is required. Copyright © 2016 Elsevier B.V. All rights reserved.

Behavioral Characteristics of Ubiquitin-Specific Peptidase 46-Deficient Mice

Science.gov (United States)

Imai, Saki; Kano, Makoto; Nonoyama, Keiko; Ebihara, Shizufumi

2013-01-01

We have previously identified Usp46, which encodes for ubiquitin-specific peptidase 46, as a quantitative trait gene affecting the immobility time of mice in the tail suspension test (TST) and forced swimming test. The mutation that we identified was a 3-bp deletion coding for lysine (Lys 92), and mice with this mutation (MT mice), as well as Usp46 KO mice exhibited shorter TST immobility times. Behavioral pharmacology suggests that the gamma aminobutyric acid A (GABAA) receptor is involved in regulating TST immobility time. In order to understand how far Usp46 controls behavioral phenotypes, which could be related to mental disorders in humans, we subjected Usp46 MT and KO mice to multiple behavioral tests, including the open field test, ethanol preference test, ethanol-induced loss of righting reflex test, sucrose preference test, novelty-suppressed feeding test, marble burying test, and novel object recognition test. Although behavioral phenotypes of the Usp46 MT and KO mice were not always identical, deficiency of Usp46 significantly affected performance in all these tests. In the open field test, activity levels were lower in Usp46 KO mice than wild type (WT) or MT mice. Both MT and KO mice showed lower ethanol preference and shorter recovery times after ethanol administration. Compared to WT mice, Usp46 MT and KO mice exhibited decreased sucrose preference, took longer latency periods to bite pellets, and buried more marbles in the sucrose preference test, novelty-suppressed feeding test, and marble burying test, respectively. In the novel object recognition test, neither MT nor KO mice showed an increase in exploration of a new object 24 hours after training. These findings indicate that Usp46 regulates a wide range of behavioral phenotypes that might be related to human mental disorders and provides insight into the function of USP46 deubiquitinating enzyme in the neural system. PMID:23472206

Behavioral characteristics of ubiquitin-specific peptidase 46-deficient mice.

Directory of Open Access Journals (Sweden)

Saki Imai

Full Text Available We have previously identified Usp46, which encodes for ubiquitin-specific peptidase 46, as a quantitative trait gene affecting the immobility time of mice in the tail suspension test (TST and forced swimming test. The mutation that we identified was a 3-bp deletion coding for lysine (Lys 92, and mice with this mutation (MT mice, as well as Usp46 KO mice exhibited shorter TST immobility times. Behavioral pharmacology suggests that the gamma aminobutyric acid A (GABAA receptor is involved in regulating TST immobility time. In order to understand how far Usp46 controls behavioral phenotypes, which could be related to mental disorders in humans, we subjected Usp46 MT and KO mice to multiple behavioral tests, including the open field test, ethanol preference test, ethanol-induced loss of righting reflex test, sucrose preference test, novelty-suppressed feeding test, marble burying test, and novel object recognition test. Although behavioral phenotypes of the Usp46 MT and KO mice were not always identical, deficiency of Usp46 significantly affected performance in all these tests. In the open field test, activity levels were lower in Usp46 KO mice than wild type (WT or MT mice. Both MT and KO mice showed lower ethanol preference and shorter recovery times after ethanol administration. Compared to WT mice, Usp46 MT and KO mice exhibited decreased sucrose preference, took longer latency periods to bite pellets, and buried more marbles in the sucrose preference test, novelty-suppressed feeding test, and marble burying test, respectively. In the novel object recognition test, neither MT nor KO mice showed an increase in exploration of a new object 24 hours after training. These findings indicate that Usp46 regulates a wide range of behavioral phenotypes that might be related to human mental disorders and provides insight into the function of USP46 deubiquitinating enzyme in the neural system.

Helminths and skewed cytokine profiles increase tuberculin skin test positivity in Warao Amerindians

NARCIS (Netherlands)

Verhagen, L. M.; Hermans, P. W. M.; Warris, A.; de Groot, R.; Maes, M.; Villalba, J. A.; del Nogal, B.; van den Hof, S.; Mughini Gras, L.; van Soolingen, D.; Pinelli, E.; de Waard, J. H.

2012-01-01

The immune regulatory mechanisms involved in the acquisition of Mycobacterium tuberculosis infection in children are largely unknown. We investigated the influence of parasitic infections, malnutrition and plasma cytokine profiles on tuberculin skin test (TST) positivity in Warao Amerindians in

Fatigue Life Prediction of Package of Suspension Automotive Under Random Vibration Based on Road Roughness

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Kazem Reza Kashyzadeh

2015-09-01

Full Text Available The impact of a suitable suspension system for passenger comfort and vehicle steering is an obvious order and direct impact on the safety of passengers must be considered, to do so different kinds of tests must be exerted, one of these is fatigue testing which is one of the most significant ones. Another issue is the high cost in practical ways, and to cope with this issue various ways must be assessed and analyzed, one of the best and the most efficient ways is modelling and testing in virtual software environments. In the present paper, predict fatigue life of suspension component and package of automotive suspension are the main purposes. First, using MATLAB software, road roughness according to the intercity roads for constant vehicle velocity (100 Km/h has been studied. After that frequency response of components has been analysed, its critical points determined to calculate the fatigue life of the part, and the amount of critical stress obtained based on Von Misses, Tresca and Max Principle criterion for a quarter car model (passive suspension System in 206 Peugeot. Fatigue life of the vehicle components are calculated in terms of kilo-Meters in specialized fatigue software such as 116944, 92638.9, 46388.9 and 191388.9 Km respectively wheel hub, pitman arm, suspension arm and package of suspension. Finally, to prove the given results of the finite element method compared with reported results by other researchers and the results match very well with those.

Controllable damping of high-Q violin modes in fused silica suspension fibers

Science.gov (United States)

Dmitriev, A. V.; Mescheriakov, S. D.; Tokmakov, K. V.; Mitrofanov, V. P.

2010-01-01

Fused silica fiber suspension of the test masses will be used in the interferometric gravitational wave detectors of the next generation. This allows a significant reduction of losses in the suspension and thermal noise associated with the suspension. Unfortunately, unwanted violin modes may be accidentally excited in the suspension fibers. The Q-factor of the violin modes also exceeds 108. They have a ring-down time that is too long and may complicate the stable control of the interferometer. Results of the investigation of a violin mode active damping system are described. An original sensor and actuator were especially developed to realize the effective coupling of a thin, optically transparent, non-conducting fused silica fiber with an electric circuit. The damping system allowed the changing of the violin mode's damping rate over a wide range.

Controlling active cabin suspensions in commercial vehicles

NARCIS (Netherlands)

Evers, W.J.E.; Besselink, I.J.M.; Teerhuis, A.P.; Knaap, van der A.C.M.; Nijmeijer, H.

2009-01-01

The field of automotive suspensions is changing. Semi-active and active suspensions are starting to become viable options for vehicle designers. Suspension design for commercial vehicles is especially interesting given its potential. An active cabin suspension for a heavy-duty truck is considered,

Electrochemical performance of solid oxide fuel cells having electrolytes made by suspension and solution precursor plasma spraying

Science.gov (United States)

Marr, M.; Kuhn, J.; Metcalfe, C.; Harris, J.; Kesler, O.

2014-01-01

Yttria-stabilized zirconia (YSZ) electrolytes were deposited by suspension plasma spraying (SPS) and solution precursor plasma spraying (SPPS). The electrolytes were evaluated for permeability, microstructure, and electrochemical performance. With SPS, three different suspensions were tested to explore the influence of powder size distribution and liquid properties. Electrolytes made from suspensions of a powder with d50 = 2.6 μm were more gas-tight than those made from suspensions of a powder with d50 = 0.6 μm. A peak open circuit voltage of 1.00 V was measured at 750 °C with a cell with an electrolyte made from a suspension of d50 = 2.6 μm powder. The use of a flammable suspension liquid was beneficial for improving electrolyte conductivity when using lower energy plasmas, but the choice of liquid was less important when using higher energy plasmas. With SPPS, peak electrolyte conductivities were comparable to the peak conductivities of the SPS electrolytes. However, leak rates through the SPPS electrolytes were higher than those through the electrolytes made from suspensions of d50 = 2.6 μm powder. The electrochemical test data on SPPS electrolytes are the first reported in the literature.

Suspensions with reduced violin string modes

International Nuclear Information System (INIS)

Lee, B H; Ju, L; Blair, D G

2006-01-01

We discuss the possibility of significantly reducing the number and Q-factor of violin string modes in the mirror suspension. Simulations of a bar-flexure suspension and an orthogonal ribbon have shown a reduction in the number of violin string modes when compared to a normal ribbon suspension. By calculating the expected suspension thermal noise, we find that the orthogonal ribbon provides a promising suspension alternative. A lower number of violin modes oscillating in the direction of the laser and a reduction in violin mode peak values of at least 23dB can be achieved with a slight increase in thermal noise above 40Hz

Suspensions with reduced violin string modes

Energy Technology Data Exchange (ETDEWEB)

Lee, B H; Ju, L; Blair, D G [School of Physics, University of Western Australia, Crawley 6009, WA (Australia)

2006-03-02

We discuss the possibility of significantly reducing the number and Q-factor of violin string modes in the mirror suspension. Simulations of a bar-flexure suspension and an orthogonal ribbon have shown a reduction in the number of violin string modes when compared to a normal ribbon suspension. By calculating the expected suspension thermal noise, we find that the orthogonal ribbon provides a promising suspension alternative. A lower number of violin modes oscillating in the direction of the laser and a reduction in violin mode peak values of at least 23dB can be achieved with a slight increase in thermal noise above 40Hz.

Development of a non-piston MR suspension rod for variable mass systems

Science.gov (United States)

Deng, Huaxia; Han, Guanghui; Zhang, Jin; Wang, Mingxian; Ma, Mengchao; Zhong, Xiang; Yu, Liandong

2018-06-01

The semi-active suspension systems for variable mass systems require long work stroke and variable damping, while the currently piston structure limits the work stroke for the magnetorheological (MR) dampers. The main work of this paper is to design a semi-active non-piston MR (NPMR) suspension rod for the reduction of the vibration of an automatic impeller washing machine, which is a typical variable mass system. The designed suspension rod locates in the suspension system that links the internal tub to the washing machine cabinet. The NPMR suspension rod includes a MR part and a air part. The MR part can provide low initial damping force and the unlimited work stroke compared with the piston MR damper. The hysteretic response tests and vibration performance evaluation with different loadings are conducted to verify the dynamic performance for the designed rod. The measured damping force of the MR part varies from 5 to 20 N. Studies of dehydration mode experiments of the washing machine indicate that its vibration acceleration with the NPMR suspension rods can reduce to half of the original passive ones in certain conditions.

Effect of suspension characteristics on in-flight particle properties and coating microstructures achieved by suspension plasma spray

Science.gov (United States)

Aubignat, E.; Planche, M. P.; Allimant, A.; Billières, D.; Girardot, L.; Bailly, Y.; Montavon, G.

2014-11-01

This paper focuses on the influence of suspension properties on the manufacturing of coatings by suspension plasma spraying (SPS). For this purpose, alumina suspensions were formulated with two different liquid phases: water and ethanol. Suspensions were atomized with a twin-fluid nozzle and injected in an atmospheric plasma jet. Suspension injection was optimized thanks to shadowgraphy observations and drop size distribution measurements performed by laser diffraction. In-flight particle velocities were evaluated by particle image velocimetry. In addition, splats were collected on glass substrates, with the same conditions as the ones used during the spray process. Scanning electron microscopy (SEM) and profilometry analyses were then performed to observe the splat morphology and thus to get information on plasma / suspension interactions, such as particle agglomeration. Finally, coatings were manufactured, characterized by SEM and compared to each other.

Antidepressant-like Effect of Kaempferol and Quercitirin, Isolated from Opuntia ficus-indica var. saboten.

Science.gov (United States)

Park, Soo-Hyun; Sim, Yun-Beom; Han, Pyung-Lim; Lee, Jin-Koo; Suh, Hong-Won

2010-06-01

Opuntia ficus-indica var. saboten. is widely cultivated in Jeju Island (South Korea) for use in manufacture of health foods. This study described antidepressant effect of two flavonoids (kaempferol and quercitrin) isolated from the Opuntia ficus-indica var. saboten. The expression of the hypothalamic POMC mRNA or plasma β-endorphin levels were increased by extract of Opuntia ficus-indica var. saboten or its flavoniods administered orally. In addition, antidepressant activity was studied using tail suspension test (TST), forced swimming test (FST) and rota-rod test in chronically restraint immobilization stress group in mice. After restraint stress (2 hrs/day for 14 days), animals were kept in cage for 14 days without any further stress, bet with drugs. Mice were fed with a diet supplemented for 14 days and during the behavioral test period with kaempferol or quercitrin (30 mg/kg/day). POMC mRNA or plasma β-endorphin level was increased by extract of Opuntia ficus-indica var. saboten and its flavoniods. In addition, immobility time in TST and FST was significantly reduced by kaempferol or quercitrin. In rota-rod test, the time of permanence was maintained to the semblance of control group in turning at 15 rpm. Our results suggest that two flavonoids (kaempferol and quercitrin) isolated from the Opuntia ficus-indica var. saboten. show a potent antidepressant effect.

Antidepressant-like Effect of Kaempferol and Quercitirin, Isolated from Opuntia ficus-indica var. saboten

Science.gov (United States)

Park, Soo-Hyun; Sim, Yun-Beom; Han, Pyung-Lim; Lee, Jin-Koo

2010-01-01

Opuntia ficus-indica var. saboten. is widely cultivated in Jeju Island (South Korea) for use in manufacture of health foods. This study described antidepressant effect of two flavonoids (kaempferol and quercitrin) isolated from the Opuntia ficus-indica var. saboten. The expression of the hypothalamic POMC mRNA or plasma β-endorphin levels were increased by extract of Opuntia ficus-indica var. saboten or its flavoniods administered orally. In addition, antidepressant activity was studied using tail suspension test (TST), forced swimming test (FST) and rota-rod test in chronically restraint immobilization stress group in mice. After restraint stress (2 hrs/day for 14 days), animals were kept in cage for 14 days without any further stress, bet with drugs. Mice were fed with a diet supplemented for 14 days and during the behavioral test period with kaempferol or quercitrin (30 mg/kg/day). POMC mRNA or plasma β-endorphin level was increased by extract of Opuntia ficus-indica var. saboten and its flavoniods. In addition, immobility time in TST and FST was significantly reduced by kaempferol or quercitrin. In rota-rod test, the time of permanence was maintained to the semblance of control group in turning at 15 rpm. Our results suggest that two flavonoids (kaempferol and quercitrin) isolated from the Opuntia ficus-indica var. saboten. show a potent antidepressant effect. PMID:22110339

Phytotherapy of experimental depression: Kalanchoe integra Var. Crenata (Andr.) Cuf Leaf Extract.

Science.gov (United States)

Kukuia, Kennedy K E; Asiedu-Gyekye, Isaac J; Woode, Eric; Biney, Robert P; Addae, Emmanuel

2015-01-01

Kalanchoe sp. have been used since 1921 for central nervous system (CNS) disorders such as psychosis and depression. It is known to possess CNS depressant effects. To investigate the antidepressant properties of the aqueous leaf extract of Kalanchoe integra. The study was carried out at the Kwame Nkrumah University of Science and Technology between 6 a.m. and 3 p.m. ICR mice were subjected to the forced swimming test (FST) and tail suspension test (TST) after they had received extract (30-300 mg/kg), fluoxetine (3-30 mg/kg), desipramine (3-30 mg/kg) orally, or water (as vehicle). In a separate experiment, mice were pre-treated with reserpine (1 mg/kg), α-methyl paratyrosine (AMPT; 400 mg/kg), both reserpine (1 mg/kg) and AMPT (200 mg/kg) concomitantly, or p-chlorophenylalanine (pCPA; 200 mg/kg) to ascertain the role of the noradrenergic and serotoninergic systems in the mode of action of the extract. Means were analyzed by analysis of variance (ANOVA) followed by Newman-Keuls' post hoc test. P < 0.05 was considered significant. In both FST and TST, the extract induced a decline in immobility, indicative of antidepressant-like effect. This diminution in immobility was reversed by pCPA, but not by reserpine and/or AMPT. The extract increased the swimming and climbing scores in the FST, suggestive of possible interaction with serotoninergic and noradrenergic systems. In the TST, the extract produced increases in both curling and swinging scores, suggestive of opioidergic monoaminergic activity, respectively. The present study has demonstrated the antidepressant potential of the aqueous leaf extract of K. integra is mediated possibly by a complex interplay between serotoninergic, opioidergic, and noradrenergic systems.

Controllable damping of high-Q violin modes in fused silica suspension fibers

Energy Technology Data Exchange (ETDEWEB)

Dmitriev, A V; Mescheriakov, S D; Mitrofanov, V P [Faculty of Physics, Moscow State University, Moscow 119991 (Russian Federation); Tokmakov, K V, E-mail: dmitriev@hbar.phys.msu.r, E-mail: mitr@hbar.phys.msu.r [Present address: Department of Physics, SUPA, University of Strathclyde, Glasgow G4 0NG (United Kingdom)

2010-01-21

Fused silica fiber suspension of the test masses will be used in the interferometric gravitational wave detectors of the next generation. This allows a significant reduction of losses in the suspension and thermal noise associated with the suspension. Unfortunately, unwanted violin modes may be accidentally excited in the suspension fibers. The Q-factor of the violin modes also exceeds 10{sup 8}. They have a ring-down time that is too long and may complicate the stable control of the interferometer. Results of the investigation of a violin mode active damping system are described. An original sensor and actuator were especially developed to realize the effective coupling of a thin, optically transparent, non-conducting fused silica fiber with an electric circuit. The damping system allowed the changing of the violin mode's damping rate over a wide range.

Controllable damping of high-Q violin modes in fused silica suspension fibers

International Nuclear Information System (INIS)

Dmitriev, A V; Mescheriakov, S D; Mitrofanov, V P; Tokmakov, K V

2010-01-01

Fused silica fiber suspension of the test masses will be used in the interferometric gravitational wave detectors of the next generation. This allows a significant reduction of losses in the suspension and thermal noise associated with the suspension. Unfortunately, unwanted violin modes may be accidentally excited in the suspension fibers. The Q-factor of the violin modes also exceeds 10 8 . They have a ring-down time that is too long and may complicate the stable control of the interferometer. Results of the investigation of a violin mode active damping system are described. An original sensor and actuator were especially developed to realize the effective coupling of a thin, optically transparent, non-conducting fused silica fiber with an electric circuit. The damping system allowed the changing of the violin mode's damping rate over a wide range.

49 CFR 570.8 - Suspension systems.

Science.gov (United States)

2010-10-01

... 49 Transportation 6 2010-10-01 2010-10-01 false Suspension systems. 570.8 Section 570.8 Transportation Other Regulations Relating to Transportation (Continued) NATIONAL HIGHWAY TRAFFIC SAFETY... Pounds or Less § 570.8 Suspension systems. (a) Suspension condition. Ball joint seals shall not be cut or...

Serial QuantiFERON-TB Gold In-Tube assay and tuberculin skin test to diagnose latent tuberculosis in household Mexican contacts: conversion and reversion rates and associated factors using conventional and borderline zone definitions

Directory of Open Access Journals (Sweden)

Joel Monárrez-Espino

2014-11-01

Full Text Available A cohort of 123 adult contacts was followed for 18‐24 months (86 completed the follow-up to compare conversion and reversion rates based on two serial measures of QuantiFERON (QFT and tuberculin skin test (TST (PPD from TUBERSOL, Aventis Pasteur, Canada for diagnosing latent tuberculosis (TB in household contacts of TB patients using conventional (C and borderline zone (BZ definitions. Questionnaires were used to obtain information regarding TB exposure, TB risk factors and socio-demographic data. QFT (IU/mL conversion was defined as 0.70 (BZ and reversion was defined as ≥0.35 to 10 (BZ and reversion was defined as ≥5 to <5 (C. The QFT conversion and reversion rates were 10.5% and 7% with C and 8.1% and 4.7% with the BZ definitions, respectively. The TST rates were higher compared with QFT, especially with the C definitions (conversion 23.3%, reversion 9.3%. The QFT conversion and reversion rates were higher for TST ≥5; for TST, both rates were lower for QFT <0.35. No risk factors were associated with the probability of converting or reverting. The inconsistency and apparent randomness of serial testing is confusing and adds to the limitations of these tests and definitions to follow-up close TB contacts.

Chain Dynamics in Magnetorheological Suspensions

Science.gov (United States)

Gast, A. P.; Furst, E. M.

1999-01-01

fluctuating chains of dipolar particles. Resolving this issue would contribute greatly to the understanding of these interesting and important materials. We have begun to test the predictions of the HT model by both examining the dynamics of individual chains and by measuring the forces between dipolar chains directly to accurately and quantitatively assess the interactions that they experience. To do so, we employ optical trapping techniques and video-microscopy to manipulate and observe our samples on the microscopic level. With these techniques, it is possible to observe chains that are fluctuating freely in three-dimensions, independent of interfacial effects. More importantly, we are able to controllably observe the interactions of two chains at various separations to measure the force-distance profile. The techniques also allow us to study the mechanical properties of individual chains and chain clusters. Our work to this point has focused on reversibly-formed dipolar chains due to field induced dipoles where the combination of this chaining, the dipolar forces, and the hydrodynamic interactions that dictate the rheology of the suspensions. One can envision, however, many situations where optical, electronic, or rheological behavior may be optimized with magneto-responsive anisotropic particles. Chains of polarizable particles may have the best properties as they can coil and flex in the absence of a field and stiffen and orient when a field is applied. We have recently demonstrated a synthesis of stable, permanent paramagnetic chains by both covalently and physically linking paramagnetic colloidal particles. The method employed allows us to create monodisperse chains of controlled length. We observed the stability, field-alignment, and rigidity of this new class of materials. The chains may exhibit unique rheological properties in an applied magnetic field over isotropic suspensions of paramagnetic particles. They are also useful rheological models as bead

Osmotic consolidation of suspensions and gels

International Nuclear Information System (INIS)

Miller, K.T.; Zukoski, C.F.

1994-01-01

An osmotic method for the consolidation of suspensions of ceramic particles is demonstrated. Concentrated solutions of poly(ethylene oxide) are separated from a suspension of ceramic particles by a semipermeable membrane, creating a gradient in solvent chemical potential. Solvent passes from the suspension into the polymer solution, lowering its free energy and consolidating the suspension. Dispersions of stable 8-nm hydrous zirconia particles were consolidated to over 47% by volume. Suspensions of α-alumina in three states of aggregation (dispersed, weakly flocculated, and strongly flocculated) were consolidated to densities greater than or equal to those produced in conventional pressure filtration. Moreover, the as-consolidated alumina bodies were partially drained of fluid during the osmotic consolidation process, producing cohesive partially dried bodies with improved handling characteristics

Decoupling Suspension Controller Based on Magnetic Flux Feedback

Directory of Open Access Journals (Sweden)

Wenqing Zhang

2013-01-01

Full Text Available The suspension module control system model has been established based on MIMO (multiple input and multiple output state feedback linearization. We have completed decoupling between double suspension points, and the new decoupling method has been applied to CMS04 magnetic suspension vehicle in national mid-low-speed maglev experiment field of Tangshan city in China. Double suspension system model is very accurate for investigating stability property of maglev control system. When magnetic flux signal is taken back to the suspension control system, the suspension module’s antijamming capacity for resisting suspension load variety has been proved. Also, the external force interference has been enhanced. As a result, the robustness and stability properties of double-electromagnet suspension control system have been enhanced.

Decoupling suspension controller based on magnetic flux feedback.

Science.gov (United States)

Zhang, Wenqing; Li, Jie; Zhang, Kun; Cui, Peng

2013-01-01

The suspension module control system model has been established based on MIMO (multiple input and multiple output) state feedback linearization. We have completed decoupling between double suspension points, and the new decoupling method has been applied to CMS04 magnetic suspension vehicle in national mid-low-speed maglev experiment field of Tangshan city in China. Double suspension system model is very accurate for investigating stability property of maglev control system. When magnetic flux signal is taken back to the suspension control system, the suspension module's antijamming capacity for resisting suspension load variety has been proved. Also, the external force interference has been enhanced. As a result, the robustness and stability properties of double-electromagnet suspension control system have been enhanced.

IFN-γ release assay conversions and reversions. Challenges with serial testing in U.S. health care workers.

Science.gov (United States)

Joshi, Manish; Monson, Thomas P; Joshi, Anita; Woods, Gail L

2014-03-01

IFN-γ release assays (IGRAs) including the QuantiFERON-TB gold in-tube test (QFT-GIT) are increasingly used in place of the tuberculin skin test (TST) in surveillance programs for Mycobacterium tuberculosis infection in the United States. However, data on conversions, reversions, and predictive value of QFT in such programs for health care workers (HCWs) are limited. The purpose of this study is to assess long-term reproducibility and conversion and reversion rates of QFT-GIT among HCWs who underwent serial testing at a tertiary care center in the United States. Retrospective chart review of HCWs at the Central Arkansas Veterans Healthcare System (CAVHS) who underwent serial testing with QFT-GIT as a part of their employee screening between November 1, 2008 and January 31, 2011. A total of 2,303 HCWs had at least 2 QFT-GITs 1 year apart. The initial QFT-GIT was positive for 69 and 2 were indeterminate. Of these 69 HCWs, 31 (45%) reverted on repeat testing, and 25 of 31 (80.6%) HCWs who reverted had a negative look-back TST. Of the 2,232 HCWs with an initial negative QFT-GIT, 71 (3.2%) converted on repeat testing. A third QFT-GIT assay was performed in 41 of the 71 converters and 90% (37 of 41) reverted back to negative. Only two HCWs had TST and QFT-GIT conversion. Poor IGRA reproducibility and a low predictive value of QFT-GIT conversions indicate that QFT-GIT with current interpretation criteria should not be used for serial screening of U.S. HCWs. Negative TSTs have higher reproducibility than QFT-GIT for serial testing of HCWs in low tuberculosis incidence settings.

Design analysis of formula student race car suspension system

Science.gov (United States)

Wirawan, Julian Wisnu; Ubaidillah, Aditra, Rama; Alnursyah, Rafli; Rahman, Rizki Abdul; Cahyono, Sukmaji Indro

2018-02-01

Design analysis of suspension especially for racecar suspension is very crucial to achieve maximum performance and handling. Suspension design may vary depending on the road terrain and the vehicle purpose itself, such as high speed or off-road vehicle. This paper focused on the suspension which used for racecar vehicle. The suspension type used was unequal double wishbone. This model is used because of its stability for high-speed usage compared to another kind of suspension. The suspension parameter was calculated to achieve desired performance. The result is the motion ratio of the designed suspension geometry. The obtained value of motion ratio was 1:2 for front suspension and 1:1 for the rear suspension. These calculation result the front suspension is still too soft, which the optimal motion ratio should be kept around 1:1 for better handling. This problem caused by the lack of space for suspension linkage.

49 CFR 570.61 - Suspension system.

Science.gov (United States)

2010-10-01

... 49 Transportation 6 2010-10-01 2010-10-01 false Suspension system. 570.61 Section 570.61... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION VEHICLE IN USE INSPECTION STANDARDS Vehicles With GVWR of More Than 10,000 Pounds § 570.61 Suspension system. (a) Suspension condition. Ball joint seals shall not be cut...

Functional Based Adaptive and Fuzzy Sliding Controller for Non-Autonomous Active Suspension System

Science.gov (United States)

Huang, Shiuh-Jer; Chen, Hung-Yi

In this paper, an adaptive sliding controller is developed for controlling a vehicle active suspension system. The functional approximation technique is employed to substitute the unknown non-autonomous functions of the suspension system and release the model-based requirement of sliding mode control algorithm. In order to improve the control performance and reduce the implementation problem, a fuzzy strategy with online learning ability is added to compensate the functional approximation error. The update laws of the functional approximation coefficients and the fuzzy tuning parameters are derived from the Lyapunov theorem to guarantee the system stability. The proposed controller is implemented on a quarter-car hydraulic actuating active suspension system test-rig. The experimental results show that the proposed controller suppresses the oscillation amplitude of the suspension system effectively.

Submerged cutting characteristics of abrasive suspension jet

International Nuclear Information System (INIS)

Shimizu, Seiji; Peng, Guoyi; Oguma, Yasuyuki; Nishikata, Hiroki

2015-01-01

An abrasive suspension jet (ASJ) formed by propelling abrasive suspension through a nozzle has a greater cutting capability than the conventional abrasive water jet. However the cutting capability of submerged ASJs decreases drastically with increasing the standoff distance and the pressure around the jet. A sheathed nozzle nozzle with ventilation for ASJs has been developed as a mean of extending the effective stand-off distance and improving the cutting capabilities under submerged condition. In the present investigation, cutting tests by ASJs in air and under submerged condition are conducted with specimens of aluminum alloy. Air coated ASJs are formed by using a sheathed nozzle with ventilation. The relative cutting depth is defined as the cutting depth is arranged effectually by the cavitation number based on the cavity pressure measured at the sheath. (author)

Vibration Reduction System Using Magnetic Suspension Technology

Directory of Open Access Journals (Sweden)

Spychała Jarosław

2015-01-01

Full Text Available The article presents considerations concerning the construction of vibration reduction system using magnetic suspension technology. Presents the results of simulation, numerical and experimental the bearingless electric motor, for which successfully used this type of solution. Positive results of research and testing have become the basis for the development of the concept of building this type of active vibration reduction system , at the same time acting as a support for a technical object, which is a jet engine. Bearing failures are manifested by loss or distortion of their mass, which leads to a total destruction of the roller bearing, and thus reflected in the security. The article presents the concept of building active magnetic suspension to eliminate the bearing system of classical rolling bearing and replace it with magnetic bearing.

A study of the free vibration of suspension rod based on four-stage arm mechanism by using computer simulation

Directory of Open Access Journals (Sweden)

Melnychuk S.V.

2016-08-01

Full Text Available We analyze the current state of the prospects and problems of using computer technology to determine the operating parameters of movement of the vehicle. Scientific works related to the study of the properties of the vehicle smooth ride are studied. The following example shows that the modern researches of smooth ride do not pay enough attention to issues associated with the processes that occur in the suspension rod of a vehicle. Scientific works related to the choice of the optimal and simple CAD system for conducting computer simulation tests are overviewed. We developed an animating model of experimental car in SOLIDWORKS environment with the staff suspension rod and the suspension rod based on four-stage arm mechanism, which allows a wide range of tests of components of the vehicle. Methodology and hardware-software complex for testing a car are developed. A test of a vehicle of category N1 is conducted. A computer simulation of the motion of the smooth ride of the car with suspension rod based on four-stage arm mechanism is conducted. The comparative analysis of suspension rod performance based on four-stage arm mechanism is conducted.

Development of an Air Pneumatic Suspension System for Transtibial Prostheses

Directory of Open Access Journals (Sweden)

Gholamhossein Pirouzi

2014-09-01

Full Text Available The suspension system and socket fitting of artificial limbs have major roles and vital effects on the comfort, mobility, and satisfaction of amputees. This paper introduces a new pneumatic suspension system that overcomes the drawbacks of current suspension systems in donning and doffing, change in volume during daily activities, and pressure distribution in the socket-stump interface. An air pneumatic suspension system (APSS for total-contact sockets was designed and developed. Pistoning and pressure distribution in the socket-stump interface were tested for the new APSS. More than 95% of the area between each prosthetic socket and liner was measured using a Tekscan F-Scan pressure measurement which has developed matrix-based pressure sensing systems. The variance in pressure around the stump was 8.76 kPa. APSS exhibits less pressure concentration around the stump, improved pressure distribution, easy donning and doffing, adjustability to remain fitted to the socket during daily activities, and more adaptability to the changes in stump volume. The volume changes were adjusted by utility of air pressure sensor. The vertical displacement point and reliability of suspension were assessed using a photographic method. The optimum pressure in every level of loading weight was 55 kPa, and the maximum displacement was 6 mm when 90 N of weight was loaded.

Tribology of swollen starch granule suspensions from maize and potato.

Science.gov (United States)

Zhang, Bin; Selway, Nichola; Shelat, Kinnari J; Dhital, Sushil; Stokes, Jason R; Gidley, Michael J

2017-01-02

The tribological properties of suspensions of cooked swollen starch granules are characterised for systems based on maize starch and potato starch. These systems are known as granule 'ghosts' due to the release (and removal) of polymer from their structure during cooking. Maize starch ghosts are less swollen than potato starch ghosts, resulting in a higher packing concentration and greater mechanical stability. In a soft-tribological contact, maize ghost suspensions reduce friction compared to the solvent (water), generate bell-shaped tribological profiles characteristic of particle entrainment and show a marked concentration dependence, whereas potato ghost suspensions exhibit lubrication behaviour similar to water. Microscopy analysis of the samples following tribological testing suggests that this is due to the rapid break-up of potato ghosts under the shear and rolling conditions within the tribological contact. A reduction in the small deformation moduli (associated with a weak gel structure) is also observed when the potato ghost suspensions are subjected to steady shear using parallel plate rheometry; both microscopy and particle size analysis show that this is accompanied by the partial shear-induced breakage of ghost particles. This interplay between particle microstructure and the resultant rheological and lubrication dynamics of starch ghost suspensions contributes to an enhanced mechanistic understanding of textural and other functional properties of cooked starches in food and other applications. Copyright © 2016 Elsevier Ltd. All rights reserved.

Fluoxetine reverses the behavioral despair induced by neurogenic stress in mice: role of N-methyl-d-aspartate and opioid receptors.

Science.gov (United States)

Haj-Mirzaian, Arya; Kordjazy, Nastaran; Ostadhadi, Sattar; Amiri, Shayan; Haj-Mirzaian, Arvin; Dehpour, AhmadReza

2016-06-01

Opioid and N-methyl-d-aspartate (NMDA) receptors mediate different effects of fluoxetine. We investigated whether opioid and NMDA receptors are involved in the protective effect of fluoxetine against the behavioral despair induced by acute physical stress in male mice. We used the forced swimming test (FST), tail suspension test (TST), and open-field test (OFT) for behavioral evaluation. We used fluoxetine, naltrexone (opioid receptor antagonist), MK-801 (NMDA receptor antagonist), morphine (opioid receptor agonist), and NMDA (NMDA receptor agonist). Acute foot-shock stress (FSS) significantly induced behavioral despair (depressive-like) and anxiety-like behaviors in tests. Fluoxetine (5 mg/kg) reversed the depressant-like effect of FSS, but it did not alter the locomotion and anxiety-like behavior in animals. Acute administration of subeffective doses of naltrexone (0.3 mg/kg) or MK-801 (0.01 mg/kg) potentiated the antidepressant-like effect of fluoxetine, while subeffective doses of morphine (1 mg/kg) and NMDA (75 mg/kg) abolished this effect of fluoxetine. Also, co-administration of subeffective doses of naltrexone (0.05 mg/kg) and MK-801 (0.003 mg/kg) with fluoxetine (1 mg/kg) induced a significant decrease in the immobility time in FST and TST. Our results showed that opioid and NMDA receptors (alone or in combination) are involved in the antidepressant-like effect of fluoxetine against physical stress.

The Mystical Suspension

Directory of Open Access Journals (Sweden)

Héctor Santiesteban Oliva

2016-11-01

Full Text Available Mistical suspension, silence, time, absolute, ontology, ineffability, aletheiaIn the mystical ecstasy there is a sensorial and intellectual suspension when contemplating the absolute, the ontological Being. Silence is not only significant: it is revealing. The greatest expression of experience inner silence . The word is insufficient when the ontological reality is revealed. Revelation or truth , the Greek concept of aletheia, takes on greater significance in that transcendental experience. It is also suspended phenomenological time and remains eternity open.

Development of a simulation model of semi-active suspension for monorail

Science.gov (United States)

Hasnan, K.; Didane, D. H.; Kamarudin, M. A.; Bakhsh, Qadir; Abdulmalik, R. E.

2016-11-01

The new Kuala Lumpur Monorail Fleet Expansion Project (KLMFEP) uses semiactive technology in its suspension system. It is recognized that the suspension system influences the ride quality. Thus, among the way to further improve the ride quality is by fine- tuning the semi-active suspension system on the new KL Monorail. The semi-active suspension for the monorail specifically in terms of improving ride quality could be exploited further. Hence a simulation model which will act as a platform to test the design of a complete suspension system particularly to investigate the ride comfort performance is required. MSC Adams software was considered as the tool to develop the simulation platform, where all parameters and data are represented by mathematical equations; whereas the new KL Monorail being the reference model. In the simulation, the model went through step disturbance on the guideway for stability and ride comfort analysis. The model has shown positive results where the monorail is in stable condition as an outcome from stability analysis. The model also scores a Rating 1 classification in ISO 2631 Ride Comfort performance which is very comfortable as an overall outcome from ride comfort analysis. The model is also adjustable, flexibile and understandable by the engineers within the field for the purpose of further development.

Assessment of drug salt release from solutions, suspensions and in situ suspensions using a rotating dialysis cell

DEFF Research Database (Denmark)

Parshad, Henrik; Frydenvang, Karla; Liljefors, Tommy

2003-01-01

buffer is used as release media. Generally, the initial release of the drug salt from in situ suspensions occurred faster as compared to conventional suspensions, probably due to incomplete precipitation of the drug salt, and hence formation of supersaturated solutions where the rate of release......A rotating dialysis cell consisting of a small (10 ml) and a large compartment (1000 ml) was used to study the release of drug salt (bupivacaine 9-anthracene carboxylate) from (i). solutions, (ii). suspensions and (iii). in situ formed suspensions. Initial release experiments from suspensions...... indicated that the release of drug salt in deionized water was predominantly limited by the diffusion across the membrane whereas it is essentially dissolution rate controlled in 0.05 M phosphate buffer (pH 7.40). Thus, the in vitro model appears to have a potential in formulation screening when phosphate...

Flow-induced structure in colloidal suspensions

Energy Technology Data Exchange (ETDEWEB)

Vermant, J [Department of Chemical Engineering, K U Leuven, W de Croylaan 46, B-3001 Leuven (Belgium); Solomon, M J [Department of Chemical Engineering, University of Michigan, Ann Arbor, MI 48109-2136 (United States)

2005-02-02

We review the sequences of structural states that can be induced in colloidal suspensions by the application of flow. Structure formation during flow is strongly affected by the delicate balance among interparticle forces, Brownian motion and hydrodynamic interactions. The resulting non-equilibrium microstructure is in turn a principal determinant of the suspension rheology. Colloidal suspensions with near hard-sphere interactions develop an anisotropic, amorphous structure at low dimensionless shear rates. At high rates, clustering due to strong hydrodynamic forces leads to shear thickening rheology. Application of steady-shear flow to suspensions with repulsive interactions induces a rich sequence of transitions to one-, two-and three-dimensional order. Oscillatory-shear flow generates metastable ordering in suspensions with equilibrium liquid structure. On the other hand, short-range attractive interactions can lead to a fluid-to-gel transition under quiescent suspensions. Application of flow leads to orientation, breakup, densification and spatial reorganization of aggregates. Using a non-Newtonian suspending medium leads to additional possibilities for organization. We examine the extent to which theory and simulation have yielded mechanistic understanding of the microstructural transitions that have been observed. (topical review)

Development of Prototype HTS Components for Magnetic Suspension Applications

Science.gov (United States)

Haldar, P.; Hoehn, J., Jr.; Selvamanickam, V.; Farrell, R. A.; Balachandran, U.; Iyer, A. N.; Peterson, E.; Salazar, K.

1996-01-01

We have concentrated on developing prototype lengths of bismuth and thallium based silver sheathed superconductors by the powder-in-tube approach to fabricate high temperature superconducting (HTS) components for magnetic suspension applications. Long lengths of mono and multi filament tapes are presently being fabricated with critical current densities useful for maglev and many other applications. We have recently demonstrated the prototype manufacture of lengths exceeding 1 km of Bi-2223 multi filament conductor. Long lengths of thallium based multi-filament conductor have also been fabricated with practical levels of critical current density and improved field dependence behavior. Test coils and magnets have been built from these lengths and characterized over a range of temperatures and background fields to determine their performance. Work is in progress to develop, fabricate and test HTS windings that will be suitable for magnetic suspension, levitation and other electric power related applications.

An efficient sensitivity analysis method for modified geometry of Macpherson suspension based on Pearson correlation coefficient

Science.gov (United States)

Shojaeefard, Mohammad Hasan; Khalkhali, Abolfazl; Yarmohammadisatri, Sadegh

2017-06-01

The main purpose of this paper is to propose a new method for designing Macpherson suspension, based on the Sobol indices in terms of Pearson correlation which determines the importance of each member on the behaviour of vehicle suspension. The formulation of dynamic analysis of Macpherson suspension system is developed using the suspension members as the modified links in order to achieve the desired kinematic behaviour. The mechanical system is replaced with an equivalent constrained links and then kinematic laws are utilised to obtain a new modified geometry of Macpherson suspension. The equivalent mechanism of Macpherson suspension increased the speed of analysis and reduced its complexity. The ADAMS/CAR software is utilised to simulate a full vehicle, Renault Logan car, in order to analyse the accuracy of modified geometry model. An experimental 4-poster test rig is considered for validating both ADAMS/CAR simulation and analytical geometry model. Pearson correlation coefficient is applied to analyse the sensitivity of each suspension member according to vehicle objective functions such as sprung mass acceleration, etc. Besides this matter, the estimation of Pearson correlation coefficient between variables is analysed in this method. It is understood that the Pearson correlation coefficient is an efficient method for analysing the vehicle suspension which leads to a better design of Macpherson suspension system.

Heavy vehicle pitch dynamics and suspension tuning

OpenAIRE

Cao, Dongpu; Rakheja, Subhash; Su, Chun-Yi

2008-01-01

The influence of suspension tuning of passenger cars on bounce and pitch ride performance has been explored in a number of studies, while only minimal efforts have been made for establishing similar rules for heavy vehicles. This study aims to explore pitch dynamics and suspension tunings of a two-axle heavy vehicle with unconnected suspension, which could also provide valuable information for heavy vehicles with coupled suspensions. Based on a generalised pitch-plane model of a two-axle heav...

Electric-surface characteristics and stability of type K coal suspensions

Energy Technology Data Exchange (ETDEWEB)

Baichenko, A A; Baran, A A; Mitina, N S; Kocherga, I I

1987-07-01

Investigates with the help of potentiometric titration, electrophoresis and conductometry the structure of double electric layer and aggregation stability of type K coal suspension at the Berezovsk preparation plant (Kuzbassugol' association). Discusses tests carried out with coal which was preliminarily crushed, sieved, crushed again in colloid mills, elutriated and separated into sedimento-stable fractions. Data obtained indicate that coal suspensions represent typical ion-stabilized dispersions, coagulation of which by electrolytes can be depicted within the framework of lyophobic colloid stability theory. Addition of double-charged gegenions considerably reduces electrokinetic potential while addition of triple-charged gegenions results in surface recharging. 10 refs.

The non-monotonic shear-thinning flow of two strongly cohesive concentrated suspensions

OpenAIRE

Buscall, Richard; Kusuma, Tiara E.; Stickland, Anthony D.; Rubasingha, Sayuri; Scales, Peter J.; Teo, Hui-En; Worrall, Graham L.

2014-01-01

The behaviour in simple shear of two concentrated and strongly cohesive mineral suspensions showing highly non-monotonic flow curves is described. Two rheometric test modes were employed, controlled stress and controlled shear-rate. In controlled stress mode the materials showed runaway flow above a yield stress, which, for one of the suspensions, varied substantially in value and seemingly at random from one run to the next, such that the up flow-curve appeared to be quite irreproducible. Th...

40 CFR 1033.340 - Suspension and revocation of certificates of conformity.

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2010-07-01

... certificates of conformity. 1033.340 Section 1033.340 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Production Line Testing and Audit Programs § 1033.340 Suspension and revocation of certificates of conformity... conformity is automatically suspended for any locomotive that fails a production line test pursuant to § 1033...

Prednisolone treatment affects the performance of the QuantiFERON gold in-tube test and the tuberculin skin test in patients with autoimmune disorders screened for latent tuberculosis infection

DEFF Research Database (Denmark)

Bélard, Erika; Semb, Synne; Ruhwald, Morten

2011-01-01

(TST). METHODS: A prospective multicenter study included 248 patients with ulcerative colitis (39), Crohn's disease (54), rheumatoid arthritis (111), and spondylo-arthropathy (44). RESULTS: QFT-IT was positive in 7/248 (3%), negative in 229 (92%), and indeterminate in 12 (5%). TST was positive in 54....../238 (23%) patients. Chest x-ray was suspect for tuberculosis in 5/236 (2%), and 35/167 (21%) had =1 risk-factors for infection with Mycobacterium tuberculosis. The main finding was a pronounced negative effect on QFT-IT and TST performance associated with prednisolone treatment. During prednisolone.......0; IQR 9.7 to >10.0; P = 0.0058). Prednisolone treatment was strongly associated with negative TST, adjusted odds ratio (AOR) 0.22 (0.1-0.8; P = 0.018), and with an increased risk of indeterminate QFT-IT results AOR 16.1 (4.1-63.2; P negative effect was found for long...

Quadruple suspension design for Advanced LIGO

International Nuclear Information System (INIS)

Robertson, N A; Cagnoli, G; Crooks, D R M; Elliffe, E; Faller, J E; Fritschel, P; Gossler, S; Grant, A; Heptonstall, A; Hough, J; Lueck, H; Mittleman, R; Perreur-Lloyd, M; Plissi, M V; Rowan, S; Shoemaker, D H; Sneddon, P H; Strain, K A; Torrie, C I; Ward, H; Willems, P

2002-01-01

In this paper, we describe the conceptual design for the suspension system for the test masses for Advanced LIGO, the planned upgrade to LIGO, the US laser interferometric gravitational-wave observatory. The design is based on the triple pendulum design developed for GEO 600 - the German/UK interferometric gravitational wave detector. The GEO design incorporates fused silica fibres of circular cross-section attached to the fused silica mirror (test mass) in the lowest pendulum stage, in order to minimize the thermal noise from the pendulum modes. The damping of the low-frequency modes of the triple pendulum is achieved by using co-located sensors and actuators at the highest mass of the triple pendulum. Another feature of the design is that global control forces acting on the mirrors, used to maintain the output of the interferometer on a dark fringe, are applied via a triple reaction pendulum, so that these forces can be implemented via a seismically isolated platform. These techniques have been extended to meet the more stringent noise levels planned for in Advanced LIGO. In particular, the Advanced LIGO baseline design requires a quadruple pendulum with a final stage consisting of a 40 kg sapphire mirror, suspended on fused silica ribbons or fibres. The design is chosen to aim to reach a target noise contribution from the suspension corresponding to a displacement sensitivity of 10 -19 m Hz -1/2 at 10 Hz at each of the test masses

Characterization of cell suspensions from solid tumors

International Nuclear Information System (INIS)

Pallavicini, M.

1985-01-01

The desirable features of cells in suspension will necessarily be dependent upon the use for which the cells were prepared. Adequate cell yield or recovery is defined by the measurement to be performed. Retention of cellular morphology is important for microscopic identification of cell types in a heterogenous cell suspension, and may be used to determine whether the cells in suspension are representative of those in the tumor in situ. Different dispersal protocols may yield cells with different degrees of clonogenicity, as well as altered biochemical features, such as loss of cellular proteins, surface antigens, nucleotide pools, etc. The quality of the cell suspension can be judged by the degree of cell clumping and level of cellular debris, both of which impact on flow cytometric measurements and studies in which the number of cells be known accurately. Finally, if the data measured on the cells in suspension are to be extrapolated to phenomena occurring in the tumor in situ, it is desirable that the cells in suspension are representative of those in the solid tumor in vivo. This report compares characteristics of tumor cell suspensions obtained by different types of selected disaggregation methods. 33 refs., 2 figs., 4 tabs

Tuberculosis screening of new hospital employees: compliance, clearance to work time, and cost using tuberculin skin test and interferon-gamma release assays.

Science.gov (United States)

Foster-Chang, Sarah A; Manning, Mary L; Chandler, Laura

2014-11-01

Selection of the most suitable test(s) for detection of Mycobacterium tuberculosis (TB) infection should be based on purpose, setting, effectiveness, and cost. Two tests are available to screen for latent TB: the tuberculin skin test (TST) and the more recent interferon-gamma release assays (IGRAs). Based on the administrative, logistic, and technical ease of use, an IGRA trial was initiated by the occupational health department at an urban Veteran's Administration health care facility for TB screening of new employees. As a result, new employees completing the pre-placement process within the organization's designated 14 days increased from 77% to 97%, new employee clearance to work time decreased from 13.18 to 5.91 days, and new employee TB screening costs were reduced by 40%. The IGRA is an acceptable alternative to the TST and has significant potential to improve the process of pre-placement TB screening. Copyright 2014, SLACK Incorporated.

Agmatine enhances antidepressant potency of MK-801 and conventional antidepressants in mice.

Science.gov (United States)

Neis, Vivian Binder; Moretti, Morgana; Manosso, Luana Meller; Lopes, Mark W; Leal, Rodrigo Bainy; Rodrigues, Ana Lúcia S

2015-03-01

Agmatine, an endogenous guanidine amine, has been shown to produce antidepressant-like effects in animal studies. This study investigated the effects of the combined administration of agmatine with either conventional monoaminergic antidepressants or the N-methyl-D-aspartate (NMDA) receptor antagonist MK-801 in the tail suspension test (TST) in mice. The aim was to evaluate the extent of the antidepressant synergism by examining the ability of a fixed dose of agmatine to shift the antidepressant potency of fluoxetine, imipramine, bupropion and MK-801. A sub-effective dose of agmatine (0.0001 mg/kg, p.o.) significantly increased the potency by which fluoxetine, imipramine, bupropion and MK-801 decreased immobility time in the TST by 2-fold (fluoxetine), 10-fold (imipramine and bupropion) and 100-fold (MK-801). Combined with previous evidence indicating a role of monoaminergic systems in the effect of agmatine, the current data suggest that agmatine may modulate monoaminergic neurotransmission and augment the activity of conventional antidepressants. Moreover, this study found that agmatine substantially augmented the antidepressant-like effect of MK-801, reinforcing the notion that this compound modulates NMDA receptor activation. These preclinical data may stimulate future clinical studies testing the effects of augmentation therapy with agmatine for the management of depressive disorders. Copyright © 2014 Elsevier Inc. All rights reserved.

Tuberculin skin testing in patients with HIV infection: limited benefit of reduced cutoff values

NARCIS (Netherlands)

Cobelens, Frank G.; Egwaga, Saidi M.; van Ginkel, Tessa; Muwinge, Hemed; Matee, Mecky I.; Borgdorff, Martien W.

2006-01-01

BACKGROUND: When determining eligibility for isoniazid preventive therapy of human immunodeficiency virus (HIV)-infected patients, the cutoff value of the tuberculin skin test (TST) is often reduced from an induration of 10 mm in diameter to one of 5 mm in diameter to compensate for loss of

13 CFR 120.660 - Suspension or revocation.

Science.gov (United States)

2010-01-01

... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Suspension or revocation. 120.660 Section 120.660 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Secondary Market Suspension Or Revocation of Participant in Secondary Market § 120.660 Suspension or revocation. (a...

Clay-cement suspensions - rheological and functional properties

Science.gov (United States)

Wojcik, L.; Izak, P.; Mastalska-Poplawska, J.; Gajek, M.

2017-01-01

The piping erosion in soil is highly unexpected in civil engineering. Elimination of such damages is difficult, expensive and time-consuming. One of the possibility is the grouting method. This method is still developed into direction of process automation as well as other useful properties of suspensions. Main way of modernization of the grouting method is connected it with rheology of injection and eventuality of fitting them to specific problems conditions. Very popular and useful became binders based on modified clays (clay-cement suspensions). Important principle of efficiency of the grouting method is using of time-dependent pseudothixotropic properties of the clay-cement suspensions. The pseudo-rheounstability aspect of the suspensions properties should be dedicated and fitted to dynamic changes of soil conditions destructions. Whole process of the modification of the suspension rheology is stimulated by the specific agents. This article contains a description of practical aspects of the rheological parameters managing of the clay-cement suspensions, dedicated to the building damages, hydrotechnic constructions etc.

Effect of buffer and antioxidant on stability of a mercaptopurine suspension.

Science.gov (United States)

Aliabadi, Hamidreza Montazeri; Romanick, Marcel; Desai, Sunil; Lavasanifar, Afsaneh

2008-03-01

The stability of standard and modified mercaptopurine suspensions when stored at room temperature and under refrigerated conditions to test the feasibility of increasing shelf life was studied. A 50-mg/mL mercaptopurine suspension was compounded by adding simple syrup, cherry syrup, and sterile water for irrigation to triturated mercaptopurine tablets for the initial reference formulation. Three additional formulations were prepared by adding an antioxidant (ascorbic acid 10 mg), a buffer (sodium phosphate monobasic monohydrate 500 mg), and a combination of antioxidant and buffer to the reference formulation. Each compounded batch was divided into two parts and stored in amber bottles at room temperature (19-23 degrees C) or under refrigerated conditions (4-8 degrees C). Analysis through high-performance liquid chromatography determined mercaptopurine levels after three and seven days and weekly thereafter for at least two weeks after shelf life was reached under specified storage conditions. Solutions with at least 93% of the original mercaptopurine concentration and with no observable sign of aggregation or cake formation were considered stable. The reference suspension of mercaptopurine showed an acceptable physical and chemical stability of up to 5 weeks when stored at room temperature. The addition of ascorbic acid extended the shelf life of the compounded suspension to 11 weeks. However, the addition of sodium phosphate monobasic did not improve the stability of mercaptopurine in the suspension. The results showed a higher stability for all formulations after storage at room temperature compared with those stored in a refrigerator. A standard oral suspension of mercaptopurine contained an acceptable drug concentration for up to 5 weeks when stored at room temperature. The addition of ascorbic acid at a concentration of 0.1% w/v to the standard formulation increased the suspension's shelf life at room temperature to 11 weeks.

Time Varying Behavior of the Loudspeaker Suspension

DEFF Research Database (Denmark)

Pedersen, Bo Rohde; Agerkvist, Finn T.

2007-01-01

The suspension part of the electrodynamic loudspeaker is often modelled as a simple linear spring with viscous damping, however the dynamic behaviour of the suspension is much more complicated than predicted by such a simple model. At higher levels the compliance becomes non-linear and often chan...... changes during excitation at high levels. This paper investigates how the compliance of the suspension depends on the excitation, i.e. level and frequency content. The measurements are compared with other known measurement methods of the suspension....

Phytotherapy of experimental depression: Kalanchoe integra Var. Crenata (Andr. Cuf Leaf Extract

Directory of Open Access Journals (Sweden)

Kennedy K E Kukuia

2015-01-01

Full Text Available Context: Kalanchoe sp. have been used since 1921 for central nervous system (CNS disorders such as psychosis and depression. It is known to possess CNS depressant effects. Aims: To investigate the antidepressant properties of the aqueous leaf extract of Kalanchoe integra. Settings and Design: The study was carried out at the Kwame Nkrumah University of Science and Technology between 6 a.m. and 3 p.m. Materials and Methods: ICR mice were subjected to the forced swimming test (FST and tail suspension test (TST after they had received extract (30-300 mg/kg, fluoxetine (3-30 mg/kg, desipramine (3-30 mg/kg orally, or water (as vehicle. In a separate experiment, mice were pre-treated with reserpine (1 mg/kg, α-methyl paratyrosine (AMPT; 400 mg/kg, both reserpine (1 mg/kg and AMPT (200 mg/kg concomitantly, or p-chlorophenylalanine (pCPA; 200 mg/kg to ascertain the role of the noradrenergic and serotoninergic systems in the mode of action of the extract. Statistical analysis used: Means were analyzed by analysis of variance (ANOVA followed by Newman-Keuls′ post hoc test. P < 0.05 was considered significant. Results: In both FST and TST, the extract induced a decline in immobility, indicative of antidepressant-like effect. This diminution in immobility was reversed by pCPA, but not by reserpine and/or AMPT. The extract increased the swimming and climbing scores in the FST, suggestive of possible interaction with serotoninergic and noradrenergic systems. In the TST, the extract produced increases in both curling and swinging scores, suggestive of opioidergic monoaminergic activity, respectively. Conclusions: The present study has demonstrated the antidepressant potential of the aqueous leaf extract of K. integra is mediated possibly by a complex interplay between serotoninergic, opioidergic, and noradrenergic systems.

Pair-correlations in swimmer suspensions

Science.gov (United States)

Nambiar, Sankalp; Subramanian, Ganesh

2017-11-01

Suspensions of rear-actuated swimming microorganisms, such as E.coli, exhibit several interesting phenomena including spontaneous pattern formation above a critical concentration, novel rheological properties, shear-induced concentration banding etc. Explanations based on mean-field theory are only qualitative, since interactions between swimmers are important for typical experimental concentrations. We analytically characterize the hydrodynamic pair-interactions in a quiescent suspension of slender straight swimmers. The pair-correlation, calculated at leading order by integrating the swimmer velocity disturbances along straight trajectories, decays as 1/r2 for r >> L (L being the swimmer size). This allows us to characterize both polar and nematic correlations in an interacting swimmer suspension. In the absence of correlations, the velocity covariance asymptotes from a constant for r > L, the latter being characteristic of a suspension of non-interacting point force-dipoles. On including correlations, the slow decay of the pair-orientation correlation leads to an additional contribution to the velocity covariance that diverges logarithmically with system size.

21 CFR 1301.36 - Suspension or revocation of registration; suspension of registration pending final order...

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2010-04-01

... 21 Food and Drugs 9 2010-04-01 2010-04-01 false Suspension or revocation of registration; suspension of registration pending final order; extension of registration pending final order. 1301.36... registration pending final order; extension of registration pending final order. (a) For any registration...

39 CFR 3001.114 - Suspension pending review.

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2010-07-01

... 39 Postal Service 1 2010-07-01 2010-07-01 false Suspension pending review. 3001.114 Section 3001... Suspension pending review. (a) Application. Application for suspension of a determination of the Postal Service to close or consolidate any post office pending the outcome of an appeal to the Postal Regulatory...

21 CFR 520.905a - Fenbendazole suspension.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Fenbendazole suspension. 520.905a Section 520.905a... DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.905a Fenbendazole suspension. (a) Specifications. Each milliliter of suspension contains 100 milligrams (mg) fenbendazole. (b...

The Design and Simulation of the Modular Vehicle Air Suspension Height Control System Based on ECAS

Directory of Open Access Journals (Sweden)

Yang Peigang

2014-02-01

Full Text Available Based on ECAS, this paper intended to develop a modular air suspension height control system with WABCO4728800010 two-position three way solenoid valves and Free scale MC9S12D64 microprocessor as its core components. And a simulation test was conducted in MATLAB/Simulink environment. The air suspension height control strategy of this system was divided into four modules: start control module, dynamic adjustment module, manual adjustment module and errors adjustment module, which were controlled by module select switch. Simulation tests indicated that the air suspension height control strategy is featured by its logical control accuracy and debug convenience, and the modular design greatly reduced the system complexity and software development cycle and costs as well.

Evaluation of the antidepressant-like effects of acute and sub-acute administration of crocin and crocetin in mice

Directory of Open Access Journals (Sweden)

Bahareh Amin

2015-08-01

Full Text Available Objective: The present study was designed to investigate the putative antidepressant effects of crocin and crocetin, two major active ingredients of Crocus sativus L. (saffron using mice in two different regimens of acute and sub-acute administration. Material and Methods: In acute treatment, antidepressant-like activities of crocin and crocetin (10, 20 and 40 mg/kg, i.p. were evaluated using forced swim test (FST. In sub-acute study (21 times with 24-h intervals, antidepressant-like effects of oral administration of drugs were examined using FST and tail suspension test (TST. Locomotor activity and motor coordination were studied using open field and rotarod tests, respectively. Results: Acute treatment with crocin (40 mg/kg and crocetin (20 and 40 mg/kg produced antidepressant-like effect in FST without affecting the baseline locomotion in mice. Sub-acute oral administration of crocin significantly decreased immobility time only at the highest dose (100 mg/kg. Crocetin (12.5, 25 and 50 mg/kg was able to decrease immobility time in FST and TST. Locomotor activity and coordination of mice were not affected by crocin or crocetin. Conclusion: Since higher doses of crocin was required to show antidepressant effects, more efficacy of crocetin may be concluded. This observation provides further support for metabolism of crocin to crocetin following oral administration.

The effect of ethanolic extract of Thymus kotschyanus on cancer cell growth in vitro and depression-like behavior in the mouse

Directory of Open Access Journals (Sweden)

Mohammad-Hossein Doosti

2018-01-01

Full Text Available Cancer and depression are known as two of the most debilitating disease and disorder increasing evidence suggest an urgent need for new therapeutic agents with lower toxicity and high efficacy. Some Thyme species extracts have remarkably been shown to positively affect depression and cancer cells. In the present study, we investigated the effect of Thymus kotschyanus on depression and cancer cells. To this end, in experiment 1, NMRI mice were treated orally with the ethanolic extract of T. kotschyanus (50, 150 and 250 mg/ml for seven days and then depression-like behavior was measured by Forced Swim Test (FST and Tail Suspension Test (TST. In experiment 2, the pharmacological effect of the extract on the lung (A549 and cervical (Hela cancer cell lines was also evaluated by MTT (3-(4,5-Dimethylthiazol-2-Yl-2,5-Diphenyltetrazolium Bromide in various concentration_(10, 5, 2.5, 1.25, 0.63, 0.31, 0.15 and 0.08 mg/ml. The results indicated that T. kotschyanus extract treatment (150 and 250 mg/kg decreased depression-like behavior in the FST and TST tests in adult mice. Moreover, the treatment inhibited cancer cell growth and viability in a dose and time-dependent manner. Collectively these findings suggest that T. kotschyanus have antidepressant and anticancer effects.

Submerged cutting characteristics of abrasive suspension jet

International Nuclear Information System (INIS)

Shimizu, Seiji; Peng, Guoyi; Oguma, Yasuyuki; Nishikata, Hiroyuki

2015-01-01

An abrasive suspension jet (ASJ) formed by propelling abrasive suspension through a nozzle has a greater cutting capability than the conventional abrasive water jet. However the cutting capability of submerged ASJs decreases drastically with increasing the standoff distance and the pressure around the jet. A sheathed nozzle with ventilation for ASJs has been developed as a mean of extending the effective stand-off distance and improving the cutting capabilities under submerged condition. In the present investigation, cutting tests by ASJs in air and under submerged condition are conducted with specimens of aluminum alloy. Air coated ASJs are formed by using a sheathed nozzle with ventilation. The relative cutting depth is defined as the cutting depth under submerged condition divided by the cutting depth in air at the same standoff distance. The relative cutting depth is arranged effectually by the cavitation number based on the cavity pressure measured at the sheath. (author)

Nonlinear Modeling and Coordinate Optimization of a Semi-Active Energy Regenerative Suspension with an Electro-Hydraulic Actuator

Directory of Open Access Journals (Sweden)

Farong Kou

2018-01-01

Full Text Available In order to coordinate the damping performance and energy regenerative performance of energy regenerative suspension, this paper proposes a structure of a vehicle semi-active energy regenerative suspension with an electro-hydraulic actuator (EHA. In light of the proposed concept, a specific energy regenerative scheme is designed and a mechanical properties test is carried out. Based on the test results, the parameter identification for the system model is conducted using a recursive least squares algorithm. On the basis of the system principle, the nonlinear model of the semi-active energy regenerative suspension with an EHA is built. Meanwhile, linear-quadratic-Gaussian control strategy of the system is designed. Then, the influence of the main parameters of the EHA on the damping performance and energy regenerative performance of the suspension is analyzed. Finally, the main parameters of the EHA are optimized via the genetic algorithm. The test results show that when a sinusoidal is input at the frequency of 2 Hz and the amplitude of 30 mm, the spring mass acceleration root meam square value of the optimized EHA semi-active energy regenerative suspension is reduced by 22.23% and the energy regenerative power RMS value is increased by 40.51%, which means that while meeting the requirements of vehicle ride comfort and driving safety, the energy regenerative performance is improved significantly.

Non-homogeneous flow profiles in sheared bacterial suspensions

Science.gov (United States)

Samanta, Devranjan; Cheng, Xiang

Bacterial suspensions under shear exhibit interesting rheological behaviors including the remarkable ``superfluidic'' state with vanishing viscosity at low shear rates. Theoretical studies have shown that such ``superfluidic'' state is linked with non-homogeneous shear flows, which are induced by coupling between nematic order of active fluids and hydrodynamics of shear flows. However, although bulk rheology of bacterial suspensions has been experimentally studied, shear profiles within bacterial suspensions have not been explored so far. Here, we experimentally investigate the flow behaviors of E. coli suspensions under planar oscillatory shear. Using confocal microscopy and PIV, we measure velocity profiles across gap between two shear plates. We find that with increasing shear rates, high-concentration bacterial suspensions exhibit an array of non-homogeneous flow behaviors like yield-stress flows and shear banding. We show that these non-homogeneous flows are due to collective motion of bacterial suspensions. The phase diagram of sheared bacterial suspensions is systematically mapped as functions of shear rates an bacterial concentrations. Our experiments provide new insights into rheology of bacterial suspensions and shed light on shear induced dynamics of active fluids. Chemical Engineering and Material Science department.

A computational model of the cognitive impact of decorative elements on the perception of suspense

Science.gov (United States)

Delatorre, Pablo; León, Carlos; Gervás, Pablo; Palomo-Duarte, Manuel

2017-10-01

Suspense is a key narrative issue in terms of emotional gratification, influencing the way in which the audience experiences a story. Virtually all narrative media uses suspense as a strategy for reader engagement regardless of the technology or genre. Being such an important narrative component, computational creativity has tackled suspense in a number of automatic storytelling. These systems are mainly based on narrative theories, and in general lack a cognitive approach involving the study of empathy or emotional effect of the environment impact. With this idea in mind, this paper reports on a computational model of the influence of decorative elements on suspense. It has been developed as part of a more general proposal for plot generation based on cognitive aspects. In order to test and parameterise the model, an evaluation based on textual stories and an evaluation based on a 3D virtual environment was run. In both cases, results suggest a direct influence of emotional perception of decorative objects in the suspense of a scene.

An efficient method for the establishment of cell suspension cultures in potato (Solanum tuberosum L.)

International Nuclear Information System (INIS)

Sajid, Z.A.

2016-01-01

Cell suspension cultures offers an In vitro system that can be used as a tool for various studies involving mutant selection, mass propagation, protoplast isolation, gene transfer and selection of cell-lines which are resistant to various biotic or abiotic stresses. Research work on the development of cell suspension cultures was carried out to establish the most efficient method in Potato (cv. Desiree). Healthy, well-proliferating tissues from different types of callus cultures (compact, friable, embryogenic or non-embryogenic) were inoculated on various media combinations, i.e., MS, MS2 or AA liquid medium containing 18.09 micro M 2, 4-D. A fixed quantity (0.5-1.0 g) of callus tissue from 60-day-old callus cultures was transferred to 10-25 ml of liquid medium in 100 ml Erlenmeyer flask. Cultures were placed on an orbital shaker and agitated at different speeds (75, 100 or 125 rpm) under 16-h photoperiod at 25 ± 2 degree C. Medium was changed after every 3 days and fractionated tissue was filtered after every 6 days through sterile mesh (100-800 micro m) to develop a cell-line by transferring resulting suspension to fresh medium under the same conditions. Results indicated that eight-week-old translucent, friable, off-white callus cultures were an excellent starting material for the initiation of homogeneous cell suspension cultures as compared to other tested sources. Of the three tested media (MS, MS2 or AA medium containing 18.09 micro M 2, 4-D), MS2 was found to be a better medium for the initiation of cell suspension cultures. Cell suspension cultures, placed in 16-h photoperiod at 25 ± 2 degree C and agitated at 120 rpm using a gyratory shaker showed excellent results. Several other factors influencing quick establishment of cell suspension cultures in this cultivar are also discussed in this communication. (author)

Testing constitutive relations by running and walking on cornstarch and water suspensions

Science.gov (United States)

Mukhopadhyay, Shomeek; Allen, Benjamin; Brown, Eric

2018-05-01

The ability of a person to run on the surface of a suspension of cornstarch and water has fascinated scientists and the public alike. However, the constitutive relation obtained from traditional steady-state rheology of cornstarch and water suspensions has failed to explain this behavior. In another paper we presented an averaged constitutive relation for impact rheology consisting of an effective compressive modulus of a system-spanning dynamically jammed structure [R. Maharjan et al., this issue, Phys. Rev. E 97, 052602 (2018), 10.1103/PhysRevE.97.052602]. Here we show that this constitutive model can be used to quantitatively predict, for example, the trajectory and penetration depth of the foot of a person walking or running on cornstarch and water. The ability of the constitutive relation to predict the material behavior in a case with different forcing conditions and flow geometry than it was obtained from suggests that the constitutive relation could be applied more generally. We also present a detailed calculation of the added mass effect to show that while it may be able to explain some cases of people running or walking on the surface of cornstarch and water for pool depths H >1.2 m and foot impact velocities VI>1.7 m/s, it cannot explain observations of people walking or running on the surface of cornstarch and water for smaller H or VI.

On the Benefits of Semi-Active Suspensions with Inerters

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Xin-Jie Zhang

2012-01-01

Full Text Available Inerters have become a hot topic in recent years especially in vehicle, train, building suspension systems, etc. Eight different layouts of suspensions were analyzed with a quarter-car model in this paper. Dimensionless root mean square (RMS responses of the sprung mass vertical acceleration, the suspension travel, and the tire deflection are derived which were used to evaluate the performance of the quarter-car model. The behaviour of semi-active suspensions with inerters using Groundhook, Skyhook, and Hybrid control has been evaluated and compared to the performance of passive suspensions with inerters. Sensitivity analysis was applied to the development of a high performance semi-active suspension with an inerter. Numerical simulations indicate that a semi-active suspension with an inerter has much better performance than the passive suspension with an inerter, especially with the Hybrid control method, which has the best compromise between comfort and road holding quality.

Tuberculosis testing among populations with high HIV risk in Tijuana, Baja California, Mexico Prueba de tuberculosis en poblaciones con riesgo alto de VIH en Tijuana, Baja California, México

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Michele G. Velasquez

2012-07-01

Full Text Available OBJECTIVE: To assess the prevalence of prior tuberculin skin testing (TST among populations at risk for HIV infection in Tijuana, Mexico, and to identify factors associated with TST. METHODS: Sex workers, injection drug users, noninjecting drug users, and homeless persons > 18 years old were recruited by using targeted sampling for risk assessment interviews and serologic testing for HIV and Mycobacterium tuberculosis infection. Univariate and multivariate logistic regression were used to identify correlates of self-reported TST history. RESULTS: Of 502 participants, 38.0% reported prior TST, which was associated with previous incarceration in the United States of America [odds ratio (OR = 13.38; 95% confidence interval (CI = 7.37-24.33] and injection drug use (OR = 1.99; 95% CI = 1.27- 3.11. Positive results on serologic tests for M. tuberculosis infection (57% and HIV (4.2% were not associated with a prior TST. CONCLUSIONS: A history of TST was lower in HIV-positive participants even though TST is indicated for persons with HIV in Mexico. Fewer than half the individuals at high risk for HIV in this study had a history of TST; however, TST was fairly common among those individuals with a prior history of incarceration. Increased tuberculosis screening is needed for populations at risk of contracting HIV in Tijuana, particularly those outside of criminal justice settings.OBJETIVO: Evaluar la prevalencia de la prueba de la tuberculina previa, e identificar los factores asociados con ella, en poblaciones con riesgo de infección por el VIH en Tijuana, México. MÉTODOS: Se reclutó a profesionales del sexo, consumidores de drogas inyectables y no inyectables y personas sin hogar > 18 años de edad mediante un muestreo dirigido a fin de efectuar entrevistas para evaluar el riesgo y pruebas serológicas para la infección por el VIH y Mycobacterium tuberculosis. Para identificar la correlación de los antecedentes de la prueba de la tuberculina

Boundary Effects and Shear Thickening of Colloidal Suspensions: A study based on measurement of Suspension Microstructure

Science.gov (United States)

Perera, M. Tharanga D.

Microstructure is key to understanding rheological behaviors of flowing particulate suspensions. During the past decade, Stokesian Dynamics simulations have been the dominant method of determining suspension microstructure. Structure results obtained numerically reveal that an anisotropic structure is formed under high Peclet (Pe) number conditions. Researchers have used various experimental techniques such as small angle neutron scattering (SANS) and light scattering methods to validate microstructure. This work outlines an experimental technique based on confocal microscopy to study microstructure of a colloidal suspension in an index-matched fluid flowing in a microchannel. High resolution scans determining individual particle locations in suspensions 30-50 vol % yield quantitative results of the local microstructure in the form of the pair distribution function, g(r). From these experimentally determined g(r), the effect of shear rate, quantified by the Peclet number as a ratio of shear and Brownian stress, on the suspension viscosity and normal stress follow that seen in macroscopic rheological measurements and simulations. It is generally believed that shear thickening behavior of colloidal suspensions is driven by the formation of hydroclusters. From measurements of particle locations, hydroclusters are identified. The number of hydroclusters grows exponentially with increasing Pe, and the onset of shear thickening is driven by the increase in formation of clusters having 5-8 particles. At higher Pe, we notice the emergence of 12 or more particle clusters. The internal structure of these hydroclusters has been investigated, and there is some evidence that particles internal to hydroclusters preferentially align along the 45° and 135° axis. Beyond observations of bulk suspension behavior, the influence of boundaries on suspension microstructure is also investigated. Experiments were performed for suspensions flowing over smooth walls, made of glass

Introducing Dual Suspension System in Road Vehicles

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Imtiaz Hussain

2013-04-01

Full Text Available The main objective of suspension system is to reduce the motions of the vehicle body with respect to road disturbances. The conventional suspension systems in road vehicles use passive elements such as springs and dampers to suppress the vibrations induced by the irregularities in the road. But these conventional suspension systems can suppress vibrations to a certain limit. This paper presents a novel idea to improve the ride quality of roads vehicles without compromising vehicle?s stability. The paper proposes the use of primary and secondary suspension to suppress the vibrations more effectively.

Numerical homogenization on approach for stokesian suspensions.

Energy Technology Data Exchange (ETDEWEB)

Haines, B. M.; Berlyand, L. V.; Karpeev, D. A. (Mathematics and Computer Science); (Department of Mathematics, Pennsylvania State Univ.)

2012-01-20

swimming resulting from bacterial alignment can significantly alter other macroscopic properties of the suspension, such as the oxygen diffusivity and mixing rates. In order to understand the unique macroscopic properties of active suspensions the connection between microscopic swimming and alignment dynamics and the mesoscopic pattern formation must be clarified. This is difficult to do analytically in the fully general setting of moderately dense suspensions, because of the large number of bacteria involved (approx. 10{sup 10} cm{sup -3} in experiments) and the complex, time-dependent geometry of the system. Many reduced analytical models of bacterial have been proposed, but all of them require validation. While comparison with experiment is the ultimate test of a model's fidelity, it is difficult to conduct experiments matched to these models assumptions. Numerical simulation of the microscopic dynamics is an acceptable substitute, but it runs into the problem of having to discretize the fluid domain with a fine-grained boundary (the bacteria) and update the discretization as the domain evolves (bacteria move). This leads to a prohibitively high number of degrees of freedom and prohibitively high setup costs per timestep of simulation. In this technical report we propose numerical methods designed to alleviate these two difficulties. We indicate how to (1) construct an optimal discretization in terms of the number of degrees of freedom per digit of accuracy and (2) optimally update the discretization as the simulation evolves. The technical tool here is the derivation of rigorous error bounds on the error in the numerical solution when using our proposed discretization at the initial time as well as after a given elapsed simulation time. These error bounds should guide the construction of practical discretization schemes and update strategies. Our initial construction is carried out by using a theoretically convenient, but practically prohibitive spectral basis

Energy-harvesting potential of automobile suspension

Science.gov (United States)

Múčka, Peter

2016-12-01

This study is aimed quantify dissipated power in a damper of automobile suspension to predict energy harvesting potential of a passenger car more accurately. Field measurements of power dissipation in a regenerative damper are still rare. The novelty is in using the broad database of real road profiles, a 9 degrees-of-freedom full-car model with real parameters, and a tyre-enveloping contact model. Results were presented as a function of road surface type, velocity and road roughness characterised by International Roughness Index. Results were calculated for 1600 test sections of a total length about 253.5 km. Root mean square of a dissipated power was calculated from 19 to 46 W for all four suspension dampers and velocity 60 km/h and from 24 to 58 W for velocity 90 km/h. Results were compared for a full-car model with a tyre-enveloping road contact, full-car and quarter-car models with a tyre-road point contact. Mean difference among three models in calculated power was a few per cent.

Identification of waves by RF magnetic probes during lower hybrid wave injection experiments on the TST-2 spherical tokamak

International Nuclear Information System (INIS)

Shinya, Takahiro; Ejiri, Akira; Takase, Yuichi

2014-01-01

RF magnetic probes can be used to measure not only the wavevector, but also the polarization of waves in plasmas. A 5-channel RF magnetic probe (5ch-RFMP) was installed in the TST-2 spherical tokamak and the waves were studied in detail during lower hybrid wave injection experiments. From the polarization measurements, the poloidal RF magnetic field is found to be dominant. In addition to polarization, components of k perpendicular to the major radial direction were obtained from phase differences among the five channels. The radial wavenumber was obtained by scanning the radial position of the 5ch-RFMP on a shot by shot basis. The measured wavevector and polarization in the plasma edge region were consistent with those calculated from the wave equation for the slow wave branch. While the waves with small and large k ∥ were excited by the antenna, only the small k ∥ component was measured by the 5ch-RFMP; this suggests that the waves with larger k ∥ were absorbed by the plasma. (author)

Electrostratic stabilization of suspensions in non-aqueous media

NARCIS (Netherlands)

Hoeven, van der P.C.

1991-01-01

Concentrated suspensions of detergent powder solids in a liquid nonionic surfactant are considered for practical application as liquid detergent products. If no precautions are taken, upon storage the viscosity of such suspensions increases and the pourability drops because the suspensions are

Rinsing with antacid suspension reduces hydrochloric acid-induced erosion.

Science.gov (United States)

Alves, Maria do Socorro Coelho; Mantilla, Taís Fonseca; Bridi, Enrico Coser; Basting, Roberta Tarkany; França, Fabiana Mantovani Gomes; Amaral, Flávia Lucisano Botelho; Turssi, Cecilia Pedroso

2016-01-01

Mouthrinsing with antacids, following erosive episodes, have been suggested as a preventative strategy to minimize tooth surface loss due to their neutralizing effect. The purpose of this in situ study was to evaluate the effect of an antacid suspension containing sodium alginate, sodium bicarbonate and calcium carbonate in controlling simulated erosion of enamel of intrinsic origin. The experimental units were 48 slabs (3×3×2mm) of bovine enamel, randomly divided among 12 volunteers who wore palatal appliances with two enamel slabs. One of them was exposed extra-orally twice a day to 25mL of a hydrochloric acid (HCl) solution (0.01M, pH 2) for 2min. There were two independent phases, lasting 5 days each. In the first phase, according to a random scheme, half of the participants rinsed with 10mL of antacid suspension (Gaviscon(®), Reckitt Benckiser Healthcare Ltd.), while the remainder was rinsed with deionized water, for 1min. For the second phase, new slabs were inserted and participants switched to the treatment not received in the first stage. Therefore, the groups were as follows: (a) erosive challenge with HCl+antacid suspension; (b) erosive challenge with HCl+deionized water (DIW); (c) no erosive challenge+antacid suspension; (d) no erosive challenge+DIW. Specimens were assessed in terms of surface loss using optical profilometry and Knoop microhardness. The data were analyzed using repeated measures two-way analysis of variance and Tukey's tests. Compared to DIW rinses, surface loss of enamel was significantly lower when using an antacid rinse following erosive challenges (p=0.015). The Knoop microhardness of the enamel was significantly higher when the antacid rinse was used (p=0.026). The antacid suspension containing sodium alginate, sodium bicarbonate and calcium carbonate, rinsed after erosive challenges of intrinsic origin, reduced enamel surface loss. Copyright © 2015 Elsevier Ltd. All rights reserved.

Novel Antidepressant-Like Activity of Caffeic Acid Phenethyl Ester Is Mediated by Enhanced Glucocorticoid Receptor Function in the Hippocampus

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Mi-Sook Lee

2014-01-01

Full Text Available Caffeic acid phenethyl ester (CAPE is an active component of propolis that has a variety of potential pharmacological effects. Although we previously demonstrated that propolis has antidepressant-like activity, the effect of CAPE on this activity remains unknown. The present study assessed whether treatment with CAPE (5, 10, and 20 µmol/kg for 21 days has an antidepressant-like effect in mice subjected to chronic unpredictable stress via tail suspension (TST and forced swim (FST tests. CAPE administration induced behaviors consistent with an antidepressant effect, evidenced by decreased immobility in the TST and FST independent of any effect on serum corticosterone secretion. Western blots, conducted subsequent to behavioral assessment, revealed that CAPE significantly decreased glucocorticoid receptor phosphorylation at S234 (pGR(S234, resulting in an increased pGR(S220/S234 ratio. We also observed negative correlations between pGR(S220/(S234 and p38 mitogen-activated protein kinase (p38MAPK phosphorylation, which was decreased by CAPE treatment. These findings suggest that CAPE treatment exerts an antidepressant-like effect via downregulation of p38MAPK phosphorylation, thereby contributing to enhanced GR function.

Tuberculin skin test and QuantiFERON® assay in young children investigated for tuberculosis in South Africa

NARCIS (Netherlands)

Moyo, S.; Isaacs, F.; Gelderbloem, S.; Verver, S.; Hawkridge, A. J.; Hatherill, M.; Tameris, M.; Geldenhuys, H.; Workman, L.; Pai, M.; Hussey, G.; Hanekom, W. A.; Mahomed, H.

2011-01-01

Although the literature on interferon-gamma release assays on tuberculosis (TB) in children has increased, data pertaining to young children remain relatively limited. To compare results from the tuberculin skin test (TST) and the QuantiFERON®-TB Gold In-Tube assay (QFT) in children aged <3 years

A Commentary on Pitfalls of Predicting Complex Traits From SNP's

DEFF Research Database (Denmark)

de los Campos, Gustavo; Sorensen, Daniel

2013-01-01

As stated by Wray and co-authors1, knowing the proportion of variance of a trait that is explained by regression on markers in the population (h2M) is relevant because, in principle, h2M represents the maximum prediction accuracy (R2TST) that is achievable in testing (TST) data if marker effects...... of h2M (Ref. 5), conseqeuenty, it is not obvious that R2TST can achieve values equal to the finite sample estimate of h2G-BLUP. In a recent article5, we studied the R2TST of G-BLUP and its relationship with h2G-BLUP. We show analytically that mis-specification of the training–testing (TRN–TST) genomic...

A theoretical approach to the re-suspension factor

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Magnoni M.

2012-04-01

Full Text Available The atmospheric re-suspension of radionuclides is a well-known phenomenon that consists in the re-injection into the atmosphere of previously deposited radioactivity. The process is driven by the action of wind on surfaces and can act as an additional source of radiation exposure by inhalation, after the deposition has finished. It is thus defined as the re-suspension factor, a parameter K generally considered as a time depending function and defined as the ratio of Ca, the volumetric air activity concentration (Bq m−3 and I0 (Bq m−2, the radioactivity deposition at time zero. The re-suspension factor concept is very useful in radioprotection in order to estimate the inhalation of radionuclides re-suspended from contaminated surfaces when direct atmospheric measurements are lacking or difficult to perform. However, the choice of the proper values of K is usually not a simple task, being quite site-specific and related to the meteorological, géomorphologie and environmental characteristics of the area to be studied. Moreover, several investigations showed clearly that the values of K are a decreasing function of time. For that reason, K values span several orders of magnitude: typical values in the range 10−5–10−10 m−1 are reported in literature for different environmental conditions and time elapsed since the deposition event. The current available models for the re-suspension factor are based on empirical formulas whose parameters are highly site dependent and cannot easily be related to some physical quantity. In this paper a simple physical model for the re-suspension factor is proposed and tested with available environmental radioactivity data (137Cs, collected since 1986 (Chernobyl fallout. The new model not only allows a satisfactory description of the experimental data like even the current empirical models do, but it is also able to connect the K values to quantities with a physical meaning (such as, for example a diffusion

Formulation design of oral pediatric Acetazolamide suspension: dose uniformity and physico-chemical stability study.

Science.gov (United States)

Santoveña, Ana; Suárez-González, Javier; Martín-Rodríguez, Cristina; Fariña, José B

2017-03-01

The formulation of an active pharmaceutical ingredient (API) as oral solution or suspension in pediatrics is a habitual practice, due to the non-existence of many commercialized medicines in pediatric doses. It is also the simplest way to prepare and administer them to this vulnerable population. The design of a formulation that assures the dose and the system stability depends on the physico-chemical properties of the API. In this study, we formulate a class IV API, Acetazolamide (AZM) as suspension for oral administration to pediatric population. The suspension must comply attributes of quality, safety and efficacy for this route of administration. We use simple compounding procedures, as well as fewer pure excipients, as recommended for children. Mass and uniformity content assays and physical and chemical stability studies were performed. To quantify the API an UPLC method was used. We verified the physico-chemical stability of the suspensions and that they passed the mass test of the European Pharmacopeia (EP), but not the dose uniformity test. This reveals that AZM must be formulated as liquid forms with a more complex system of excipients (not usually indicated in pediatrics), or otherwise solid forms capable of assuring uniformity of mass and dose for every dosage unit.

Adaptive suspension strategy for a double wishbone suspension through camber and toe optimization

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C. Kavitha

2018-02-01

Full Text Available A suspension system is responsible for the safety of vehicle during its manoeuvre. It serves the dual purpose of providing stability to the vehicle while providing a comfortable ride quality to the occupants. Recent trends in suspension system have focused on improving comfort and handling of vehicles while keeping the cost, space and feasibility of manufacturing in the constraint. This paper proposes a method for improving handling characteristics of a vehicle by controlling camber and toe angle using variable length arms in an adaptive manner. In order to study the effect of dynamic characteristics of the suspension system, a simulation study has been done in this work. A quarter car physical model with double wishbone suspension geometry is modelled in SolidWorks. It is then imported and simulated using SimMechanics platform in MATLAB. The output characteristics of the passive system (without variable length arms were validated on MSC ADAMS software. The adaptive system intends to improve vehicle handling characteristics by controlling the camber and toe angles. This is accomplished by two telescopic arms with an actuator which changes the camber and toe angle of the wheel dynamically to deliver best possible traction and manoeuvrability. Two PID controllers are employed to trigger the actuators based on the camber and toe angle from the sensors for reducing the error existing between the actual and desired value. The arms are driven by actuators in a closed loop feedback manner with help of a separate control system. Comparison between active and passive systems is carried out by analysing graphs of various parameters obtained from MATLAB simulation. From the results, it is observed that there is a reduction of 58% in the camber and 96% in toe gain. Hence, the system provides the scope of considerable adaptive strategy in controlling dynamic characteristics of the suspension system.

System and technique for ultrasonic characterization of settling suspensions

Energy Technology Data Exchange (ETDEWEB)

Greenwood, Margaret S [Richland, WA; Panetta, Paul D [Richland, WA; Bamberger, Judith A [Richland, WA; Pappas, Richard A [Richland, WA

2006-11-28

A system for determining properties of settling suspensions includes a settling container, a mixer, and devices for ultrasonic interrogation transverse to the settling direction. A computer system controls operation of the mixer and the interrogation devices and records the response to the interrogating as a function of settling time, which is then used to determine suspension properties. Attenuation versus settling time for dilute suspensions, such as dilute wood pulp suspension, exhibits a peak at different settling times for suspensions having different properties, and the location of this peak is used as one mechanism for characterizing suspensions. Alternatively or in addition, a plurality of ultrasound receivers are arranged at different angles to a common transmitter to receive scattering responses at a variety of angles during particle settling. Angular differences in scattering as a function of settling time are also used to characterize the suspension.

Compounding rifampin suspensions with improved injectability for nasogastric enteral feeding tube administration.

Science.gov (United States)

de Villiers, Melgardt M; Vogel, Laura; Bogenschutz, Monica C; Fingerhut, Bonnie J; D'Silva, Joseph B; Moore, Anne

2010-01-01

Often medications that have to be administered to patients via a nasogastric enteral feeding tubes are only available as tablets and capsules with no suitable commercial liquid alternatives. In such situations, pharmacists and nurses have to compound the tablets and capsule contents into liquid suspension formulations for dosing. The risk of occlusion of the enteral tubes during administration is reduced by employing liquid suspensions that are composed of small and uniform particles, not subject to rapid rates of settling, resistant to caking, and easily and uniformly re-suspended upon agitation. Present techniques often employ a manual process, such as a mortar and pestle, to accomplish the particle size reduction and subsequent incorporation into a suitable liquid diluent. A new compounding device has been invented that employs an automated wet-milling process in a single-use disposable plastic container to compound the suspensions. The two processes were compared using Rifampin capsules and various liquid diluents. A prototype version of the new device was employed in the experiments. The physical characteristics of the compounded suspensions were evaluated by determining sedimentation rate, sedimentation volume, and particle size and shape using laser light scattering, optical microscopy, and scanning electron microscopy techniques. The use characteristic of the compounded suspensions was evaluated using a nasogastric tube inject ability test. The results indicated that suspensions prepared using the new device were more resistant to sedimentation and caking and were easier to re-disperse into a uniform mixture by gentle shaking. The results were a consequence of the particles generated by the new device which were found to be smaller and more uniform in shape and size. The suspensions prepared using the new device did not cause blockage of the enteral feeding tubes in comparison to those prepared using a mortar and pastle. In conclusion, the results indicate

Graphite suspension in carbon dioxide

International Nuclear Information System (INIS)

Roche, R.

1965-01-01

Since 1963 the Atomic Division of SNECMA has been conducting, under a contract with the CEA, an experimental work with a two-component fluid comprised of carbon dioxide and small graphite particles. The primary purpose was the determination of basic engineering information pertaining to the stability and the flowability of the suspension. The final form of the experimental loop consists mainly of the following items: a light-phase compressor, a heavy-phase pump, an electrical-resistance type heater section, a cooling heat exchanger, a hairpin loop, a transparent test section and a separator. During the course of the testing, it was observed that the fluid could be circulated quite easily in a broad range of variation of the suspension density and velocity - density from 30 to 170 kg/m 3 and velocity from 2 to 24 m/s. The system could be restarted and circulation maintained without any difficulty, even with the heavy-phase pump alone. The graphite did not have a tendency to pack or agglomerate during operation. No graphite deposition was observed on the wall of the tubing. A long period run (250 hours) has shown the evolution of the particle dimensions. Starting with graphite of surface area around 20 m 2 /g (graphite particles about 1 μ), the powder surface area reaches an asymptotic value of 300 m 2 /g (all the particles less than 0.3 μ). Moisture effect on flow stability, flow distribution between two parallel channels, pressure drop in straight tubes, recompression ratio in diffusers were also investigated. (author) [fr

An isotropic suspension system for a biaxial accelerometer using electroplated thick metal with a HAR SU-8 mold

International Nuclear Information System (INIS)

Lee, Jin Seung; Lee, Seung S

2008-01-01

In this paper, a novel approach is developed to design an isotropic suspension system using thick metal freestanding micro-structures combining bulk micro-machining with electroplating based on a HAR SU-8 mold. An omega-shape isotropic suspension system composed of circular curved beams that have free switching of imaginary boundary conditions is proposed. This novel isotropic suspension design is not affected by geometric dimensional parameters and always achieves matching stiffness along the principle axes of elasticity. Using the finite element method, the isotropic suspension system was compared with an S-shaped meandering suspension system. In order to realize the suggested isotropic suspension system, a cost-effective fabrication process using electroplating with the SU-8 mold was developed to avoid expensive equipment and materials such as deep reactive-ion etching (DRIE) or a silicon-on-insulator (SOI) wafer. The fabricated isotropic suspension system was verified by electromagnetic actuation experiments. Finally, a biaxial accelerometer with isotropic suspension system was realized and tested using a vibration generator system. The proposed isotropic suspension system and the modified surface micro-machining technique based on electroplating with an SU-8 mold can contribute towards minimizing the system size, simplifying the system configuration, reducing the system price of and facilitating mass production of various types of low-cost sensors and actuators

Effects of fetal microwave radiation exposure on offspring behavior in mice

International Nuclear Information System (INIS)

Zhang Yanchun; Li Zhihui; Gao Yan; Zhang Chenggang

2015-01-01

The recent rapid development of electronic communication techniques is resulting in a marked increase in exposure of humans to electromagnetic fields (EMFs). This has raised public concerns about the health hazards of long-term environmental EMF exposure for fetuses and children. Some studies have suggested EMF exposure in children could induce nervous system disorders. However, gender-dependent effects of microwave radiation exposure on cognitive dysfunction have not previously been reported. Here we investigated whether in utero exposure to 9.417-GHz microwave throughout gestation (Days 3.5–18) affected behavior, using the open field test (OFT), elevated-plus maze (EPM), tail suspension test (TST), forced swimming test (FST) and Morris water maze (MWM). We found that mice showed less movement in the center of an open field (using the OFT) and in an open arm (using the EPM) after in utero exposure to 9.417-GHz radiation, which suggested that the mice had increased anxiety-related behavior. Mice demonstrated reduced immobility in TST and FST after in utero exposure to 9.417-GHz radiation, which suggested that the mice had decreased depression-related behavior. From the MWM test, we observed that male offspring demonstrated decreased learning and memory, while females were not affected in learning and memory, which suggested that microwaves had gender-dependent effects. In summary, we have provided the first experimental evidence of microwaves inducing gender-dependent effects. (author)

Study on Dynamic Behaviour of Wishbone Suspension System

International Nuclear Information System (INIS)

Kamal, M; Rahman, M M

2012-01-01

This paper presents the characteristic model of the wishbone suspension system using the quarter car model approach. Suspension system in an automobile provides vehicle control and passenger comfort by providing isolation from road disturbances. This makes it essential that the detailed behavior of suspension should be known to optimize the performance. A kinetic study is performed using multi body system (MBS) analysis. The dirt road profile is considered as an applied loading. The spring constant, damping coefficient and sprung mass are studied on the performance of the suspension system. It can be observed that the spring constant is inversely related with time required to return to initial position and the amount of deformations. The damping ratio affects the suppression of spring oscillations, beyond a certain limit damping ration has the negligible effect. Sprung mass effected the equilibrium position of the suspension system with a small effect on its oscillation behavior. It is shown that the spring constant, damping ratio and sprung mass are significant parameters to design the suspension system. This study is essential for complete understanding of working of the suspension system and a future study with real geometries.

Pregnancy differentially impacts performance of latent tuberculosis diagnostics in a high-burden setting.

Directory of Open Access Journals (Sweden)

Jyoti S Mathad

Full Text Available Targeted screening for latent TB infection (LTBI in vulnerable populations is a recommended TB control strategy. Pregnant women are at high risk for developing TB and likely to access healthcare, making pregnancy an important screening opportunity in developing countries. The sensitivity of the widely-used tuberculin skin test (TST, however, may be reduced during pregnancy.We performed a cross-sectional study comparing the TST with the QuantiFERON Gold In-tube (QGIT in 401 HIV-negative women presenting antepartum (n = 154, at delivery (n = 148, or postpartum (n = 99 to a government hospital in Pune, India. A subset of 60 women enrolled during pregnancy was followed longitudinally and received both tests at all three stages of pregnancy.The QGIT returned significantly more positive results than the TST. Of the 401 women in the cross-sectional study, 150 (37% had a positive QGIT, compared to 59 (14% for the TST (p<0.005. Forty-nine (12% did not have their TST read. Of 356 who had both results available, 46 (13% were concordant positive, 91 (25% were discordant (12 (3% TST+/QGIT-; 79 (22% TST-/QGIT+, and 206 (57% concordant negative. Comparison by stage of pregnancy revealed that QGIT percent positivity remained stable between antepartum and delivery, unlike TST results (QGIT 31-32% vs TST 11-17%. Median IFN-γ concentration was lower at delivery than in antepartum or postpartum (1.66 vs 2.65 vs 8.99 IU/mL, p = 0.001. During postpartum, both tests had significantly increased positives (QGIT 31% vs 32% vs 52%, p = 0.01; TST 17% vs 11% vs 25%, p<0.005. The same trends were observed in the longitudinal subset.Timing and choice of LTBI test during pregnancy impact results. QGIT was more stable and more closely approximated the LTBI prevalence in India. But pregnancy stage clearly affects both tests, raising important questions about how the complex immune changes brought on by pregnancy may impact LTBI screening.

Pregnancy differentially impacts performance of latent tuberculosis diagnostics in a high-burden setting.

Science.gov (United States)

Mathad, Jyoti S; Bhosale, Ramesh; Sangar, Vikrant; Mave, Vidya; Gupte, Nikhil; Kanade, Savita; Nangude, Ashwini; Chopade, Kavita; Suryavanshi, Nishi; Deshpande, Prasad; Kulkarni, Vandana; Glesby, Marshall J; Fitzgerald, Daniel; Bharadwaj, Renu; Sambarey, Pradeep; Gupta, Amita

2014-01-01

Targeted screening for latent TB infection (LTBI) in vulnerable populations is a recommended TB control strategy. Pregnant women are at high risk for developing TB and likely to access healthcare, making pregnancy an important screening opportunity in developing countries. The sensitivity of the widely-used tuberculin skin test (TST), however, may be reduced during pregnancy. We performed a cross-sectional study comparing the TST with the QuantiFERON Gold In-tube (QGIT) in 401 HIV-negative women presenting antepartum (n = 154), at delivery (n = 148), or postpartum (n = 99) to a government hospital in Pune, India. A subset of 60 women enrolled during pregnancy was followed longitudinally and received both tests at all three stages of pregnancy. The QGIT returned significantly more positive results than the TST. Of the 401 women in the cross-sectional study, 150 (37%) had a positive QGIT, compared to 59 (14%) for the TST (p<0.005). Forty-nine (12%) did not have their TST read. Of 356 who had both results available, 46 (13%) were concordant positive, 91 (25%) were discordant (12 (3%) TST+/QGIT-; 79 (22%) TST-/QGIT+), and 206 (57%) concordant negative. Comparison by stage of pregnancy revealed that QGIT percent positivity remained stable between antepartum and delivery, unlike TST results (QGIT 31-32% vs TST 11-17%). Median IFN-γ concentration was lower at delivery than in antepartum or postpartum (1.66 vs 2.65 vs 8.99 IU/mL, p = 0.001). During postpartum, both tests had significantly increased positives (QGIT 31% vs 32% vs 52%, p = 0.01; TST 17% vs 11% vs 25%, p<0.005). The same trends were observed in the longitudinal subset. Timing and choice of LTBI test during pregnancy impact results. QGIT was more stable and more closely approximated the LTBI prevalence in India. But pregnancy stage clearly affects both tests, raising important questions about how the complex immune changes brought on by pregnancy may impact LTBI screening.

Determination of residual 4'-aminomethyl-4,5',8-trimethylpsoralen and mutagenicity testing following psoralen plus UVA treatment of platelet suspensions

International Nuclear Information System (INIS)

Wagner, S.J.; Robinette, D.; Dodd, R.Y.; White, R.; Wolf, L.; Chapman, J.; Lawlor, T.E.

1993-01-01

Psoralens and UVa light have been used in the laboratory to study the inactivation of viruses that may be infrequently present in platelet concentrates prepared for transfusion. In order to evaluate safety aspects of the treatment of platelet suspensions with 4'-aminomethyl-4,5'8-trimethylpsoralen (AMT), the authors have investigated the residual levels and mutagenic potential of AMT after UVA phototreatment. The results suggest that residual available AMT is mutagenic in the AMES test and that the observed frameshift mutations may be caused by binding of AMt or its metabolites to nucleic acids in the absence of UVA light. (Author)

Attractive and repulsive magnetic suspension systems overview

Science.gov (United States)

Cope, David B.; Fontana, Richard R.

1992-01-01

Magnetic suspension systems can be used in a wide variety of applications. The decision of whether to use an attractive or repulsive suspension system for a particular application is a fundamental one which must be made during the design process. As an aid to the designer, we compare and contrast attractive and repulsive magnetic suspension systems and indicate whether and under what conditions one or the other system is preferred.

Ensemble-average versus suspension-scale Cauchy continuum-mechanical definitions of stress in polarized suspensions: Global homogenization of a dilute suspension of dipolar spherical particles

International Nuclear Information System (INIS)

Almog, Y.; Brenner, H.

1999-01-01

The macroscale rheological properties of a dilute suspension exposed to a uniform external field and composed of identical, rigid, inhomogeneous, dipolar, spherical particles dispersed in an incompressible Newtonian fluid and possessing the same mean density as the latter fluid are derived from knowledge of its microscale properties by applying a global ensemble-averaging technique. Each dipole, which is permanently embedded in the particle, is assumed to be generated by the presence of an inhomogeneous external body-force field in the particle interior resulting from the action of the uniform external field on an inhomogeneous distribution of interior matter. It is shown that although the ensemble-average stress tensor is symmetric, the suspension nevertheless behaves macroscopically as if it possessed an asymmetric stress tensor. This seeming contradiction can be traced to the fact that the average body force acting on the contents of any arbitrarily drawn volume lying in the interior of the suspension does not vanish despite the fact that each particle is 'neutrally buoyant'. That this force is not zero stems from the fact that some particles necessarily straddle the closed surface bounding that volume, and that the distribution of external body forces over the interiors of these particles is nonuniform. As such, that portion of the spherical particle lying outside of the surface enclosing the domain exerts a force on the remaining portion of the sphere lying within that domain. We then demonstrate that the natural macroscopic model, which is derived by equating the divergence of the suspension-scale stress appearing in that model to the ensemble-average external body-force field, and which predicts a symmetric stress tensor, is macroscopically deficient with respect to the more intuitive asymmetric stress model usually proposed by continuum mechanicians for such a suspension. It is shown that the latter, continuum-mechanical model recovers all the physically

Fracture in Kaolinite clay suspensions

Science.gov (United States)

Kosgodagan Acharige, Sebastien; Jerolmack, Douglas J.; Arratia, Paulo E.

2017-11-01

Clay minerals are involved in many natural (landslides, river channels) and industrial processes (ceramics, cosmetics, oil recovery). They are plate shaped charged colloids and exhibit different flow properties than simpler colloids when suspended in a liquid such as thixotropy and shear-banding. kaolinite platelets are non-swelling, meaning that the stacks formed by the platelets do not have water layers, and thus the suspension does not have a sol-gel transition. However, it has been shown that kaolinite suspensions possesses a non-zero yield stress even at low concentrations, indicating that the particles arrange themselves in a structure through attractive interactions. Here, we experimentally investigate the sedimentation of kaolinite suspensions in a Hele-Shaw cell. The sedimentation of these dilute suspensions can display solid behavior like fracture, revealed in cross-polarized light, which is linked to the failure of the weakly-bonded structure (typical yield stress 10-2 Pa). By changing the interaction potential of the particles (by sonication or introducing salts), we show through these sedimentation experiments, how the fracture pattern can be avoided. Research was sponsored by the Army Research Laboratory and was accomplished under Grant Number 569074.

Incident Mycobacterium tuberculosis infection in household contacts of infectious tuberculosis patients in Brazil.

Science.gov (United States)

Jones-López, Edward C; Acuña-Villaorduña, Carlos; Fregona, Geisa; Marques-Rodrigues, Patricia; White, Laura F; Hadad, David Jamil; Dutra-Molina, Lucilia Pereira; Vinhas, Solange; McIntosh, Avery I; Gaeddert, Mary; Ribeiro-Rodrigues, Rodrigo; Salgame, Padmini; Palaci, Moises; Alland, David; Ellner, Jerrold J; Dietze, Reynaldo

2017-08-18

In household contact investigations of tuberculosis (TB), a second tuberculin skin test (TST) obtained several weeks after a first negative result consistently identifies individuals that undergo TST conversion. It remains unclear whether this delay in M. tuberculosis infection is related to differences in the infectious exposure, TST boosting, partial host resistance, or some other factor. We conducted a household contact study Vitória, Brazil. Between 2008 and 2013, we identified culture-positive pulmonary TB patients and evaluated their household contacts with both a TST and interferon gamma release assay (IGRA), and identified TST converters at 8-12 weeks post study enrollment. Contacts were classified as TST-positive (≥10 mm) at baseline, TST converters, or persistently TST-negative. We compared TST converters to TST-positive and to TST-negative contacts separately, using generalized estimating equations. We enrolled 160 index patients and 838 contacts; 523 (62.4%) were TST+, 62 (7.4%) TST converters, and 253 (30.2%) TST-. TST converters were frequently IGRA- at 8-12 weeks. In adjusted analyses, characteristics distinguishing TST converters from TST+ contacts (no contact with another TB patient and residence ownership) were different than those differentiating them from TST- contacts (stronger cough in index patient and contact BCG scar). The individual risk and timing of M. tuberculosis infection within households is variable and dependent on index patient, contact and environmental factors within the household, and the surrounding community. Our findings suggest a threshold effect in the risk of infection in humans.

36 CFR 296.10 - Suspension and revocation of permits.

Science.gov (United States)

2010-07-01

... AGRICULTURE PROTECTION OF ARCHAEOLOGICAL RESOURCES: UNIFORM REGULATIONS § 296.10 Suspension and revocation of... correct the situation which led to suspension of the permit. (b) Suspension or revocation for management...

Size, velocity, and concentration in suspension measurements of spherical droplets and cylindrical jets.

Science.gov (United States)

Onofri, F; Bergougnoux, L; Firpo, J L; Misguich-Ripault, J

1999-07-20

The principle of an optical technique for simultaneous velocity, size, and concentration in suspension measurements of spherical droplets and cylindrical jets is proposed. This technique is based on phase Doppler anemometry working in the dual burst technique configuration. The particle size and velocity are deduced from the reflected signal phase and frequency, whereas the amplitude ratio between the refracted and the reflected signals is used for measuring the concentration of small scatterers inside the particles. Numerical simulations, based on geometrical optics and a Monte Carlo model, and an experimental validation test on cylindrical jets made of various suspensions, are used to validate the principle of the proposed technique. It is believed that this new technique could be useful in investigating processes in which liquid suspensions are sprayed for surface coating, drying, or combustion applications.

Linear viscoelastic properties of aging suspensions

NARCIS (Netherlands)

Purnomo, E.H.; Purnomo, E.H; van den Ende, Henricus T.M.; Mellema, J.; Mugele, Friedrich Gunther

2006-01-01

We have examined the linear viscoelastic behavior of poly-N-isopropylacrylamide (PNIPAM) microgel suspensions in order to obtain insight in the aging processes in these densely packed suspensions at various temperatures below the volume transition temperature. The system is found to display a strong

Dynamic analysis of suspension cable based on vector form intrinsic finite element method

Science.gov (United States)

Qin, Jian; Qiao, Liang; Wan, Jiancheng; Jiang, Ming; Xia, Yongjun

2017-10-01

A vector finite element method is presented for the dynamic analysis of cable structures based on the vector form intrinsic finite element (VFIFE) and mechanical properties of suspension cable. Firstly, the suspension cable is discretized into different elements by space points, the mass and external forces of suspension cable are transformed into space points. The structural form of cable is described by the space points at different time. The equations of motion for the space points are established according to the Newton’s second law. Then, the element internal forces between the space points are derived from the flexible truss structure. Finally, the motion equations of space points are solved by the central difference method with reasonable time integration step. The tangential tension of the bearing rope in a test ropeway with the moving concentrated loads is calculated and compared with the experimental data. The results show that the tangential tension of suspension cable with moving loads is consistent with the experimental data. This method has high calculated precision and meets the requirements of engineering application.

39 CFR 320.9 - Revocation or amendment of suspensions.

Science.gov (United States)

2010-07-01

... SUSPENSION OF THE PRIVATE EXPRESS STATUTES § 320.9 Revocation or amendment of suspensions. These suspensions... of operations (in dollar or volume terms, whichever is larger) lower than that antedating the...

Nonlinear Predictive Sliding Mode Control for Active Suspension System

Directory of Open Access Journals (Sweden)

Dazhuang Wang

2018-01-01

Full Text Available An active suspension system is important in meeting the requirements of the ride comfort and handling stability for vehicles. In this work, a nonlinear model of active suspension system and a corresponding nonlinear robust predictive sliding mode control are established for the control problem of active suspension. Firstly, a seven-degree-of-freedom active suspension model is established considering the nonlinear effects of springs and dampers; and secondly, the dynamic model is expanded in the time domain, and the corresponding predictive sliding mode control is established. The uncertainties in the controller are approximated by the fuzzy logic system, and the adaptive controller reduces the approximation error to increase the robustness of the control system. Finally, the simulation results show that the ride comfort and handling stability performance of the active suspension system is better than that of the passive suspension system and the Skyhook active suspension. Thus, the system can obviously improve the shock absorption performance of vehicles.

41 CFR 105-74.670 - Suspension.

Science.gov (United States)

2010-07-01

... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false Suspension. 105-74.670 Section 105-74.670 Public Contracts and Property Management Federal Property Management Regulations System...-GOVERNMENTWIDE REQUIREMENTS FOR DRUG-FREE WORKPLACE (FINANCIAL ASSISTANCE) Definitions § 105-74.670 Suspension...

Behaviour of humic-bentonite aggregates in diluted suspensions ...

African Journals Online (AJOL)

Formation and disaggregation of micron-size aggregates in a diluted suspension made up of HSs and bentonite (B) were studied by tracing distribution of aggregate sizes and their counts in freshly prepared and aged suspensions, and at high (10 000) and low (1.0) [HS]/[B] ratios. Diluted HSB suspensions are unstable ...

Effects of Agmatine on Depressive-Like Behavior Induced by Intracerebroventricular Administration of 1-Methyl-4-phenylpyridinium (MPP(+)).

Science.gov (United States)

Moretti, Morgana; Neis, Vivian Binder; Matheus, Filipe Carvalho; Cunha, Mauricio Peña; Rosa, Priscila Batista; Ribeiro, Camille Mertins; Rodrigues, Ana Lúcia S; Prediger, Rui Daniel

2015-10-01

Considering that depression is a common non-motor comorbidity of Parkinson's disease and that agmatine is an endogenous neuromodulator that emerges as a potential agent to manage diverse central nervous system disorders, this study investigated the antidepressant-like effect of agmatine in mice intracerebroventricularly (i.c.v.) injected with the dopaminergic neurotoxin 1-methyl-4-phenylpyridinium (MPP(+)). Male C57BL6 mice were treated with agmatine (0.0001, 0.1 or 1 mg/kg) and 60 min later the animals received an i.c.v. injection of MPP(+) (1.8 µg/site). Twenty-four hours after MPP(+) administration, immobility time, anhedonic behavior, and locomotor activity were evaluated in the tail suspension test (TST), splash test, and open field test, respectively. Using Western blot analysis, we investigated the putative modulation of MPP(+) and agmatine on striatal and frontal cortex levels of tyrosine hydroxylase (TH) and brain-derived neurotrophic factor (BDNF). MPP(+) increased the immobility time of mice in the TST, as well as induced an anhedonic-like behavior in the splash test, effects which were prevented by pre-treatment with agmatine at the three tested doses. Neither drug, alone or in combination, altered the locomotor activity of mice. I.c.v. administration of MPP(+) increased the striatal immunocontent of TH, an effect prevented by the three tested doses of agmatine. MPP(+) and agmatine did not alter the immunocontent of BDNF in striatum and frontal cortex. These results demonstrate for the first time the antidepressant-like effects of agmatine in an animal model of depressive-like behavior induced by the dopaminergic neurotoxin MPP(+).

Yield stress of alumina-zirconia suspensions

International Nuclear Information System (INIS)

Ramakrishnan, V.; Pradip; Malghan, S.G.

1996-01-01

The yield stress of concentrated suspensions of alumina, zirconia, and mixed alumina-zirconia powders was measured by the vane technique as a function of solids loading, relative amounts of alumina and zirconia, and pH. At the isoelectric point (IEP), the yield stress varied as the fourth power of the solids loading. The relative ratio of alumina and zirconia particles was important in determining the yield stress of the suspension at the IEP. The yield stress of single and mixed suspensions showed a marked variation with pH. The maximum value occurred at or near the IEP of the suspension. The effect of electrical double-layer forces on the yield stress can be described on the basis of the Derjaguin-Landau-Verwey-Overbeek (DLVO) theory. A normalized yield stress--that is, the ratio of the yield stress at a given pH to the yield stress at the IEP predicted by this model--showed good correlation with experimental data

5 MJ flywheel based on bulk HTS magnetic suspension

Science.gov (United States)

Poltavets, V.; Kovalev, K.; Ilyasov, R.; Glazunov, A.; Maevsky, V.; Verzbitsky, L.; Akhmadyshev, V.; Shikov, A.

2014-05-01

Nowadays the flywheel energy storage systems (FES) are developed intensively as uninterruptible power supply (UPS) devices for on-land and transport (especially airborne) applications worldwide. This work is devoted to the FES with magnetic suspension on the base of bulk HTS YBCO elements and permanent magnets. The developed FES is intended to be used as UPS in Russian atomic industry in case of an emergency. For the successful design of the FES the following questions should be solved: design of the motor/generator, design of the rotor (flywheel), design of the bearing system, design of the control system and system of power load matching, design of the cooling system. The developed small-scale FES with the stored energy 0.5 MJ was used to solve these basic questions. The elaborated FES consists of the synchronous electric machine with permanent magnets, the solid flywheel with axial magnetic suspension on the base of YBCO bulks and permanent magnets, the system of control and power load matching, and the system of liquid nitrogen cooling. The results of theoretical modeling of different schematics of magnetic suspension and experimental investigations of the constructed FES are presented. The design of the future full-scale FES with the stored energy ~5 MJ and output power up to 100 kW is described. The test results of the flywheel rotor and HTS magnetic suspension of 5 MJ FES are presented. This work is done under support of Rosatom within the frames of Russian Project "Superconducting Industry"

Vaginal vault suspension during hysterectomy for benign indications

DEFF Research Database (Denmark)

Bonde, Lisbeth; Noer, Mette Calundann; Møller, Lars Alling

2017-01-01

Introduction and hypothesis: Several suspension methods are used to try to prevent pelvic organ prolapse (POP) after hysterectomy. We aimed to evaluate agreement on terminology and surgical procedure of these methods. Methods: We randomly chose 532 medical records of women with a history......: Regarding medical records, agreement on terminology was good among patients undergoing pooled suspension in cases of hysterectomy via the abdominal and vaginal route (agreement 78.7, 92.3%). Regarding videos, agreement on surgical procedure was good among pooled suspension patients in cases of hysterectomy...... via the abdominal, laparoscopic, and vaginal routes (agreement 88.9, 97.8, 100%). Agreement on individual suspension methods differed regarding both medical records (agreement 0–90.1%) and videos (agreement 0–100%). Conclusions: Agreement on terminology and surgical procedure regarding suspension...

Microstructural Dynamics and Rheology of Suspensions of Rigid Fibers

Science.gov (United States)

Butler, Jason E.; Snook, Braden

2018-01-01

The dynamics and rheology of suspensions of rigid, non-Brownian fibers in Newtonian fluids are reviewed. Experiments, theories, and computer simulations are considered, with an emphasis on suspensions at semidilute and concentrated conditions. In these suspensions, interactions between the particles strongly influence the microstructure and rheological properties of the suspension. The interactions can arise from hydrodynamic disturbances, giving multibody interactions at long ranges and pairwise lubrication forces over short distances. For concentrated suspensions, additional interactions due to excluded volume (contacts) and adhesive forces are addressed. The relative importance of the various interactions as a function of fiber concentration is assessed.

Toxicity of xenobiotics during sulfate, iron, and nitrate reduction in primary sewage sludge suspensions

DEFF Research Database (Denmark)

Elsgaard, Lars

2010-01-01

The effect and persistence of six organic xenobiotics was tested under sulfate-, iron-, and nitrate-reducing conditions in primary sewage sludge suspensions. The xenobiotics tested were acenaphthene, phenanthrene, di(2-ethylhexyl)phthalate (DEHP), 4-nonylphenol (4-NP), linear alkylbenzene sulfonate...

Introducing Dual Suspension System in Road Vehicles

OpenAIRE

Imtiaz Hussain; Jawaid Daudpoto; Ali Asghar Memon

2013-01-01

The main objective of suspension system is to reduce the motions of the vehicle body with respect to road disturbances. The conventional suspension systems in road vehicles use passive elements such as springs and dampers to suppress the vibrations induced by the irregularities in the road. But these conventional suspension systems can suppress vibrations to a certain limit. This paper presents a novel idea to improve the ride quality of roads vehicles without compromising vehicle?s stability...

Rheology of dense suspensions of non colloidal particles

Science.gov (United States)

Guazzelli, Élisabeth

2017-06-01

Dense suspensions are materials with broad applications both in industrial processes (e.g. waste disposal, concrete, drilling muds, metalworking chip transport, and food processing) and in natural phenomena (e.g. flows of slurries, debris, and lava). Despite its long research history and its practical relevance, the mechanics of dense suspensions remain poorly understood. The major difficulty is that the grains interact both by hydrodynamic interactions through the liquid and by mechanical contact. These systems thus belong to an intermediate regime between pure suspensions and granular flows. We show that we can unify suspension and granular rheology under a common framework by transferring the frictional approach of dry granular media to wet suspensions of spherical particles. We also discuss non-Newtonian behavior such as normal-stress differences and shear-induced migration. Beyond the classical problem of dense suspension of hard spheres which is far from being completely resolved, there are also entirely novel avenues of study concerning more complex mixtures of particles and fluids such as those involving other types of particles (e.g. fibers) or non-Newtonian fluids that we will also address.

Analysis of Train Suspension System Using MR dampers

Science.gov (United States)

RamaSastry, DVA; Ramana, K. V.; Mohan Rao, N.; Siva Kumar, SVR; Priyanka, T. G. L.

2016-09-01

This paper deals with introducing MR dampers to the Train Suspension System for improving the ride comfort of the passengers. This type of suspension system comes under Semi-active suspension system which utilizes the properties of MR fluid to damp the vibrations. In case of high speed trains, the coach body is subjected to vibrations due to vertical displacement, yaw and pitch movements. When the body receives these disturbances from the ground,the transmission of vibrations to the passenger increases which affect the ride comfort. In this work, the equations of motion of suspension system are developed for both conventional passive system and semi-active system and are modelled in Matlab/Simulink and analysis has been carried out. The passive suspension system analysis shows that it is taking more time to damp the vibrations and at the same time the transmissibility of vibrations is more.Introducing MR dampers,vertical and angular displacements of the body are computed and compared. The results show that the introduction of MR dampers into the train suspension system improves ride comfort.

Pitched Blade Turbine Efficiency at Particle Suspension

Directory of Open Access Journals (Sweden)

D. Ceres

2010-01-01

Full Text Available Mixing suspensions is a very important hydraulic operation. The pitched six-blade turbine is a widely-used axial-flow impeller. This paper deals with effect relative impeller size and particle content on theefficiency of a pitched six-blade turbine at particle suspension. Two pitched six-blade turbines were used in model measurements of just suspension impeller speed. The ratios of the vessel to agitator diameter D/d were 3 and 4.5. The measurements were carried out in a dish-bottomed vessel 300 mm in diameter. The just suspension impeller speeds were measured using an electrochemical method, and were checked visually. A 2.5 % NaCl water solution was used as the liquid phase, and glass particles with four equivalent diameters between 0.18 and 0.89 mmand volumetric concentration from 2.5 % to 40% were usedasthesolid phase. The criterion values πs=Po√Fr'3(d/D7 were calculated from the particle suspension and power consumption measurements. The dependencies of πs on particle content cv show that larger agitators are more efficient for higher particle content.

Network synthesis and parameter optimization for vehicle suspension with inerter

Directory of Open Access Journals (Sweden)

Long Chen

2016-12-01

Full Text Available In order to design a comfortable-oriented vehicle suspension structure, the network synthesis method was utilized to transfer the problem into solving a timing robust control problem and determine the structure of “inerter–spring–damper” suspension. Bilinear Matrix Inequality was utilized to obtain the timing transfer function. Then, the transfer function of suspension system can be physically implemented by passive elements such as spring, damper, and inerter. By analyzing the sensitivity and quantum genetic algorithm, the optimized parameters of inerter–spring–damper suspension were determined. A quarter-car model was established. The performance of the inerter–spring–damper suspension was verified under random input. The simulation results manifested that the dynamic performance of the proposed suspension was enhanced in contrast with traditional suspension. The root mean square of vehicle body acceleration decreases by 18.9%. The inerter–spring–damper suspension can inhibit the vertical vibration within the frequency of 1–3 Hz effectively and enhance the performance of ride comfort significantly.

THE APPLICATION OF DETERMINATION METHOD OF DYNAMIC PROPERTIES OF TRACK SUSPENSION IN LABVIEW

Directory of Open Access Journals (Sweden)

Jan WARCZEK

2015-03-01

Full Text Available The article presents the results of simulation tests, which aim was to validate the method of determining the damping characteristics of the suspension vehicle. The developed method was used for the implementation of the program in LabView environment. The study used the results of simulations carried out on the DOF model of a truck suspension. Ultimately, the presented method and its version in use as a program running on the Windows platform is to be applied in the diagnosis of vehicles with a maximum permissible weight of over 3.5 tonnes.

Digital control of wind tunnel magnetic suspension and balance systems

Science.gov (United States)

Britcher, Colin P.; Goodyer, Michael J.; Eskins, Jonathan; Parker, David; Halford, Robert J.

1987-01-01

Digital controllers are being developed for wind tunnel magnetic suspension and balance systems, which in turn permit wind tunnel testing of aircraft models free from support interference. Hardware and software features of two existing digital control systems are reviewed. Some aspects of model position sensing and system calibration are also discussed.

An Active Seat Controller with Vehicle Suspension Feedforward and Feedback States: An Experimental Study

Directory of Open Access Journals (Sweden)

Abdulaziz Alfadhli

2018-04-01

Full Text Available Active seat suspensions can be used to reduce the harmful vertical vibration of a vehicle’s seat by applying an external force using a closed loop controller. Many of the controllers found in the literature are difficult to implement practically, because they are based on using unavailable or difficult and costly measurements. This paper presents both simulation and experimental studies of five novel, simple, and cost-effective control strategies to be used for an active seat suspension in order to improve ride comfort at low frequencies below 20 Hz. These strategies use available and measurable feedforward (preview information states from the vehicle secondary suspension, as well as feedback states from the seat suspension, together with gains optimised to minimise the occupant vibration. The gains were optimised using a genetic algorithm (GA, with a fitness function based on the seat effective amplitude transmissibility (SEAT factor. Constraints on the control force and the seat suspension stroke were also included in the optimisation algorithm. Simulation and laboratory experimental tests were carried out to assess the performance of the proposed controllers according to the ISO 2631-1 standard, in both the frequency and time domains with a range of different road profiles. The experimental tests were performed using a multi-axis simulation table (MAST and a physical active seat suspension configured as a hardware-in-loop (HIL simulation with a virtual linear quarter vehicle model (QvM. The results demonstrate that the proposed controllers substantially attenuate the vertical vibration at the driver’s seat compared with both a passive and a proportional-integral-derivative (PID active seat suspension and thus improve ride comfort together with reducing vibration-linked health risks. Moreover, experimental results show that employing both feedforward information and feedback vehicle body and seat acceleration signals in the controller

Acute agmatine administration, similar to ketamine, reverses depressive-like behavior induced by chronic unpredictable stress in mice.

Science.gov (United States)

Neis, Vivian B; Bettio, Luis E B; Moretti, Morgana; Rosa, Priscila B; Ribeiro, Camille M; Freitas, Andiara E; Gonçalves, Filipe M; Leal, Rodrigo B; Rodrigues, Ana Lúcia S

Agmatine is an endogenous neuromodulator that has been shown to have antidepressant-like properties. We have previously demonstrated that it can induce a rapid increase in BDNF levels after acute administration, suggesting that agmatine may be a fast-acting antidepressant. To investigate this hypothesis, the present study evaluated the effects of a single administration of agmatine in mice subjected to chronic unpredictable stress (CUS), a model of depression responsive only to chronic treatment with conventional antidepressants. The ability of agmatine to reverse CUS-induced behavioral and biochemical alterations was evaluated and compared with those elicited by the fast-acting antidepressant (ketamine) and the conventional antidepressant (fluoxetine). After exposed to CUS for 14days, mice received a single oral dose of agmatine (0.1mg/kg), ketamine (1mg/kg) or fluoxetine (10mg/kg), and were submitted to behavioral evaluation after 24h. The exposure to CUS caused an increased immobility time in the tail suspension test (TST) but did not change anhedonic-related parameters in the splash test. Our findings provided evidence that, similarly to ketamine, agmatine is able to reverse CUS-induced depressive-like behavior in the TST. Western blot analyses of prefrontal cortex (PFC) demonstrated that mice exposed to CUS and/or treated with agmatine, fluoxetine or ketamine did not present alterations in the immunocontent of synaptic proteins [i.e. GluA1, postsynaptic density protein 95 (PSD-95) and synapsin]. Altogether, our findings indicate that a single administration of agmatine is able to reverse behavioral alterations induced by CUS in the TST, suggesting that this compound may have fast-acting antidepressant-like properties. However, there was no alteration in the levels of synaptic proteins in the PFC, a result that need to be further investigated in other time points. Copyright © 2016 Elsevier Inc. All rights reserved.

Adaptive magnetorheological seat suspension for shock mitigation

Science.gov (United States)

Singh, Harinder Jit

This research focuses on theoretical and experimental analysis of an adaptive seat suspension employing magnetorheological energy absorber with the objective of minimizing injury potential to seated occupant of different weights subjected to broader crash intensities. The research was segmented into three tasks: (1) development of magnetorheological energy absorber, (2) biodynamic modeling of a seated occupant, and (3) control schemes for shock mitigation. A linear stroking semi-active magnetorheological energy absorber (MREA) was designed, fabricated and tested for intense impact conditions with piston velocities up to 8 m/s. MREA design was optimized on the basis of Bingham-plastic model (BPM model) in order to maximize the energy absorption capabilities at high impact velocities. Computational fluid dynamics and magnetic FE analysis were conducted to validate MREA performance. Subsequently, low-speed cyclic testing (0-2 Hz subjected to 0-5.5 A) and high-speed drop testing (0-4.5 m/s at 0 A) were conducted for quantitative comparison with the numerical simulations. Later, a nonlinear four degrees-of-freedom biodynamic model representing a seated 50th percentile male occupant was developed on the basis of experiments conducted on Hybrid II 50th percentile male anthropomorphic test device. The response of proposed biodynamic model was compared quantitatively against two different biodynamic models from the literature that are heavily implemented for obtaining biodynamic response under impact conditions. The proposed biodynamic model accurately predicts peak magnitude, overall shape and the duration of the biodynamic transient response, with minimal phase shift. The biodynamic model was further validated against 16 impact tests conducted on horizontal accelerator facility at NAVAIR for two different shock intensities. Compliance effects of human body were also investigated on the performance of adaptive seat suspension by comparing the proposed biodynamic model

Nanometer-scale sizing accuracy of particle suspensions on an unmodified cell phone using elastic light scattering.

Science.gov (United States)

Smith, Zachary J; Chu, Kaiqin; Wachsmann-Hogiu, Sebastian

2012-01-01

We report on the construction of a Fourier plane imaging system attached to a cell phone. By illuminating particle suspensions with a collimated beam from an inexpensive diode laser, angularly resolved scattering patterns are imaged by the phone's camera. Analyzing these patterns with Mie theory results in predictions of size distributions of the particles in suspension. Despite using consumer grade electronics, we extracted size distributions of sphere suspensions with better than 20 nm accuracy in determining the mean size. We also show results from milk, yeast, and blood cells. Performing these measurements on a portable device presents opportunities for field-testing of food quality, process monitoring, and medical diagnosis.

Novel antidepressant candidate RO-05 modulated glucocorticoid receptors activation and FKBP5 expression in chronic mild stress model in rats.

Science.gov (United States)

Xing, Y; Hou, J; Meng, Q; Yang, M; Kurihara, H; Tian, J

2015-04-02

In this study, a novel TRI (triple reuptake inhibitors) antidepressant candidate RO-05 (4-[1-[1-(benzoyloxy)cyclohexyl]-2-(dimethylamino)ethyl]-phenyl benzoate) was investigated in TST (tail suspension test), FST (forced swimming test) and CMS (chronic mild stress) model. Results showed RO-05 significantly decreased the immobility time in FST and TST at 4.5-, 9-, 18-mg/kg in rats and 9-, 18-, 36-mg/kg in mice. Chronic administration of 18-mg/kg RO-05 improved the behavioral index, anhedonia and normalized the hyperactivity of HPA (hypothalamic-pituitary-adrenal axis) of CMS rats. We further investigated the possible mechanisms of RO-05 in the CMS model. Eighteen milligrams per kilogram of RO-05 chronic administration significantly reversed the increase of mRNA and protein expression of FKBP5 in the CMS rat hippocampus, which facilitated the activation of GR- (glucocorticoid receptor) and GR-responsive gene Foxo1 expression. RO-05 also elevated the expression of BDNF (brain-derived neurotrophic factor) in CMS rat hippocampus. In summary, our results indicated that RO-05 is a promising antidepressant candidate. The possible antidepressant mechanisms of RO-05 were the modulation of FKBP5 expression, GR activation, corresponding inhibition of HPA axis hyperactivity, and the increase of BDNF expression. Copyright © 2015 IBRO. Published by Elsevier Ltd. All rights reserved.

40 CFR 94.512 - Suspension and revocation of certificates of conformity.

Science.gov (United States)

2010-07-01

... certificates of conformity. 94.512 Section 94.512 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Manufacturer Production Line Testing Programs § 94.512 Suspension and revocation of certificates of conformity. (a) The certificate of conformity is suspended with respect to any engine that fails a production...

40 CFR 91.511 - Suspension and revocation of certificates of conformity.

Science.gov (United States)

2010-07-01

... certificates of conformity. 91.511 Section 91.511 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Production Line Testing Program § 91.511 Suspension and revocation of certificates of conformity. (a) The certificate of conformity is automatically suspended with respect to any engine failing pursuant to paragraph...

Optimization of Automotive Suspension System by Design of Experiments: A Nonderivative Method

Directory of Open Access Journals (Sweden)

Anirban C. Mitra

2016-01-01

Full Text Available A lot of health issues like low back pain, digestive disorders, and musculoskeletal disorders are caused as a result of the whole body vibrations induced by automobiles. This paper is concerned with the enhancement and optimization of suspension performance by using factorial methods of Design of Experiments, a nonderivative method. It focuses on the optimization of ride comfort and determining the parameters which affect the suspension behavior significantly as per the guidelines stated in ISO 2631-1:1997 standards. A quarter car test rig integrated with a LabVIEW based data acquisition system was developed to understand the real time behavior of a vehicle. In the pilot experiment, only three primary suspension parameters, that is, spring-stiffness, damping, and sprung mass, were considered and the full factorial method was implemented for the purpose of optimization. But the regression analysis of the data obtained rendered a very low goodness of fit which indicated that other parameters are likely to influence the response. Subsequently, steering geometry angles, camber and toe and tire pressure, were included in the design. Fractional factorial method with six factors was implemented to optimize ride comfort. The resultant optimum combination was then verified on the test rig with high correlation.

49 CFR 393.207 - Suspension systems.

Science.gov (United States)

2010-10-01

... braking system. The vehicle shall be level (not tilting to the left or right). Air leakage shall not be... 49 Transportation 5 2010-10-01 2010-10-01 false Suspension systems. 393.207 Section 393.207... NECESSARY FOR SAFE OPERATION Frames, Cab and Body Components, Wheels, Steering, and Suspension Systems § 393...

Magnetic Suspension Technology Workshop

International Nuclear Information System (INIS)

Keckler, C.R.; Groom, N.J.; Britcher, C.P.

1993-01-01

In order to identify the state of magnetic suspension technology in such areas as rotating systems, pointing of experiments or subsystems, payload isolation, and superconducting materials, a workshop on Magnetic Suspension Technology was held at the Langley Research Center in Hampton, Virginia, on 2-4 Feb. 1988. The workshop included five technical sessions in which a total of 24 papers were presented. The technical sessions covered the areas of pointing, isolation, and measurement, rotating systems, modeling and control, and superconductors. A list of attendees is provided. Separate abstracts have been prepared for articles from this report

Solid lipid nanoparticles suspension versus commercial solutions for dermal delivery of minoxidil.

Science.gov (United States)

Padois, Karine; Cantiéni, Céline; Bertholle, Valérie; Bardel, Claire; Pirot, Fabrice; Falson, Françoise

2011-09-15

Solid lipid nanoparticles have been reported as possible carrier for skin drug delivery. Solid lipid nanoparticles are produced from biocompatible and biodegradable lipids. Solid lipid nanoparticles made of semi-synthetic triglycerides stabilized with a mixture of polysorbate and sorbitan oleate were loaded with 5% of minoxidil. The prepared systems were characterized for particle size, pH and drug content. Ex vivo skin penetration studies were performed using Franz-type glass diffusion cells and pig ear skin. Ex vivo skin corrosion studies were realized with a method derived from the Corrositex(®) test. Solid lipid nanoparticles suspensions were compared to commercial solutions in terms of skin penetration and skin corrosion. Solid lipid nanoparticles suspensions have been shown as efficient as commercial solutions for skin penetration; and were non-corrosive while commercial solutions presented a corrosive potential. Solid lipid nanoparticles suspensions would constitute a promising formulation for hair loss treatment. Copyright © 2011 Elsevier B.V. All rights reserved.

Evaluation of a Prototype Hybrid Vacuum Pump to Provide Vacuum-Assisted Suspension for Above-Knee Prostheses.

Science.gov (United States)

Major, Matthew J; Caldwell, Ryan; Fatone, Stefania

2015-12-01

Vacuum-assisted suspension (VAS) of prosthetic sockets utilizes a pump to evacuate air from between the prosthetic liner and socket, and are available as mechanical or electric systems. This technical note describes a hybrid pump that benefits from the advantages of mechanical and electric systems, and evaluates a prototype as proof-of-concept. Cyclical bench testing of the hybrid pump mechanical system was performed using a materials testing system to assess the relationship between compression cycles and vacuum pressure. Phase 1 in vivo testing of the hybrid pump was performed by an able-bodied individual using prosthesis simulator boots walking on a treadmill, and phase 2 involved an above-knee prosthesis user walking with the hybrid pump and a commercial electric pump for comparison. Bench testing of 300 compression cycles produced a maximum vacuum of 24 in-Hg. In vivo testing demonstrated that the hybrid pump continued to pull vacuum during walking, and as opposed to the commercial electric pump, did not require reactivation of the electric system during phase 2 testing. The novelty of the hybrid pump is that while the electric system provides rapid, initial vacuum suspension, the mechanical system provides continuous air evacuation while walking to maintain suspension without reactivation of the electric system, thereby allowing battery power to be reserved for monitoring vacuum levels.

36 CFR 25.3 - Supervision; suspensions.

Science.gov (United States)

2010-07-01

... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Supervision; suspensions. 25.3 Section 25.3 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR NATIONAL MILITARY PARKS; LICENSED GUIDE SERVICE REGULATIONS § 25.3 Supervision; suspensions. (a) The guide service will operate under the direction...

Rheology of dense suspensions of non colloidal particles

Directory of Open Access Journals (Sweden)

Guazzelli Élisabeth

2017-01-01

Full Text Available Dense suspensions are materials with broad applications both in industrial processes (e.g. waste disposal, concrete, drilling muds, metalworking chip transport, and food processing and in natural phenomena (e.g. flows of slurries, debris, and lava. Despite its long research history and its practical relevance, the mechanics of dense suspensions remain poorly understood. The major difficulty is that the grains interact both by hydrodynamic interactions through the liquid and by mechanical contact. These systems thus belong to an intermediate regime between pure suspensions and granular flows. We show that we can unify suspension and granular rheology under a common framework by transferring the frictional approach of dry granular media to wet suspensions of spherical particles. We also discuss non-Newtonian behavior such as normal-stress differences and shear-induced migration. Beyond the classical problem of dense suspension of hard spheres which is far from being completely resolved, there are also entirely novel avenues of study concerning more complex mixtures of particles and fluids such as those involving other types of particles (e.g. fibers or non-Newtonian fluids that we will also address.

Rheological Properties of Aqueous Nanometric Alumina Suspensions

Energy Technology Data Exchange (ETDEWEB)

Li, Chuanping [Iowa State Univ., Ames, IA (United States)

2004-01-01

Colloidal processing is an effective and reliable approach in the fabrication of the advanced ceramic products. Successful colloidal processing of fine ceramic powders requires accurate control of the rheological properties. The accurate control relies on the understanding the influences of various colloidal parameters on the rheological properties. Almost all research done on the rheology paid less attention to the interactions of particle and solvent. However, the interactions of the particles are usually built up through the media in which the particles are suspended. Therefore, interactions of the particle with the media, the adsorbed layers on the particle surface, and chemical and physical properties of media themselves must influence the rheology of the suspension, especially for the dense suspensions containing nanosized particles. Relatively little research work has been reported in this area. This thesis addresses the rheological properties of nanometric alumina aqueous suspensions, and paying more attention to the interactions between particle and solvent, which in turn influence the particle-particle interactions. Dense nanometric alumina aqueous suspensions with low viscosity were achieved by environmentally-benign fructose additives. The rheology of nanometric alumina aqueous suspensions and its variation with the particle volume fraction and concentration of fructose were explored by rheometry. The adsorptions of solute (fructose) and solvent (water) on the nanometric alumina particle surfaces were measured and analyzed by TG/DSC, TOC, and NMR techniques. The mobility of water molecules in the suspensions and its variation with particle volume fractions and fructose additive were determined by the ¹⁷O NMR relaxation method. The interactions between the nanometric alumina particles in water and fructose solutions were investigated by AFM. The results indicated that a large number of water layers were physically bound on the particles

Well-dispersed gold nanowire suspension for assembly application

International Nuclear Information System (INIS)

Xu Cailing; Zhang Li; Zhang Haoli; Li Hulin

2005-01-01

A method for fabricating well-dispersed nanowire suspension has been demonstrated in the paper. Thin gold nanowires were prepared by template synthesis, and then functionalized with sulphonate group-terminated thiols before suspended in different solvents. The degree of aggregation of the obtained suspension was evaluated with transmission electron microscopy (TEM) and UV-vis spectroscopy. It was found that the degree of aggregation was predominated by the solvents, and the best degree of dispersion was obtained when isopropyl alcohol (IPA) was used as the solvent. The gold nanowires from the suspension can be selectively assembled onto chemically patterned substrates. This well-dispersed nanowire suspension is potentially useful for fabricating novel nanodevices

Muscle Activation during Push-Ups with Different Suspension Training Systems

Directory of Open Access Journals (Sweden)

Joaquin Calatayud, Sebastien Borreani, Juan C. Colado, Fernando F Martín, Michael E. Rogers

2014-09-01

Full Text Available The purpose of this study was to analyze upper extremity and core muscle activation when performing push-ups with different suspension devices. Young fit male university students (n = 29 performed 3 push-ups each with 4 different suspension systems. Push-up speed was controlled using a metronome and testing order was randomized. Average amplitude of the electromyographic root mean square of Triceps Brachii, Upper Trapezius, Anterior Deltoid, Clavicular Pectoralis, Rectus Abdominis, Rectus Femoris, and Lumbar Erector Spinae was recorded. Electromyographic signals were normalized to the maximum voluntary isometric contraction (MVIC. Electromyographic data were analyzed with repeated-measures analysis of variance with a Bonferroni post hoc. Based upon global arithmetic mean of all muscles analyzed, the suspended push-up with a pulley system provided the greatest activity (37.76% of MVIC; p < 0.001. Individually, the suspended push-up with a pulley system also provided the greatest triceps brachii, upper trapezius, rectus femoris and erector lumbar spinae muscle activation. In contrast, more stable conditions seem more appropriate for pectoralis major and anterior deltoid muscles. Independent of the type of design, all suspension systems were especially effective training tools for reaching high levels of rectus abdominis activation.

Synthesis of Some Novel Thiadiazole Derivative Compounds and Screening Their Antidepressant-Like Activities

Directory of Open Access Journals (Sweden)

Nafiz Öncü Can

2018-03-01

Full Text Available Novel thiadiazole derivatives were synthesized through the reaction of acetylated 2-aminothiadiazole and piperazine derivatives. The chemical structures of the compounds were clarified by Infrared Spectroscopy (IR, 1H Nuclear Magnetic Resonance Spectroscopy (1H-NMR, 13C Nuclear Magnetic Resonance Spectroscopy (13C-NMR and Electronspray Ionisation Mass Spectroscopy (ESI-MS spectroscopic methods. Antidepressant-like activities were evaluated by the tail-suspension (TST and modified forced swimming (MFST methods. Besides, possible influence of the test compounds on motor activities of the animals were examined by activity cage tests. In the TST, administration of the compounds 2c, 2d, 2e, 2f, 2g and 2h significantly decreased the immobility time of mice regarding the control values. Further, in the MFST, the same compounds reduced the total number of immobility behaviors while increasing swimming performance. However, no change was observed in the total number of climbing behaviors. These data suggested that compounds 2c, 2d, 2e, 2f, 2g and 2h possess notable antidepressant-like activities. Reference drug fluoxetine (10 mg/kg was also exhibited its antidepressant activity, as expected. No significant difference was seen between the locomotor activity values of the test groups signifying that observed antidepressant-like activities are specific. Theoretical calculation of absorption, distribution, metabolism, excretion (ADME properties for the obtained compounds were performed and obtained data supported the antidepressant-like potential of these novel thiadiazole derivatives.

In situ characterization of organo-modified and unmodified montmorillonite aqueous suspensions by UV-visible spectroscopy.

Science.gov (United States)

Alin, Jonas; Rubino, Maria; Auras, Rafael

2015-10-15

UV-visible (UV-Vis) spectroscopy (Tyndall spectra) was applied and tested for its ability to measure organo-modified and unmodified montmorillonite (MMT) clays in aqueous suspensions. A full factorial design of experiments was used to study the influence of pH, NaCl and clay concentrations on the average particle size of the clay agglomerates. The methodology was evaluated by observing results that were consistent with previous research about the unmodified clay's behavior in aqueous suspensions. The results from this evaluation corresponded to accepted theories about the unmodified clay's behavior, indicating that the methodology is precise enough to distinguish the effects of the studied factors on these clay suspensions. The effect of clay concentration was related to the amount of ions per clay particle for the unmodified clay, but was not significant for the organo-modified MMT. The average particle size of the organo-modified MMT in suspension was significantly larger than that of the unmodified clay. Size of the organo-modified MMT agglomerates in suspension decreased in the presence of NaCl and at both high and low pH; this behavior was opposite to that of the unmodified clay. These results demonstrate that the UV-Vis methodology is well-suited for characterizing clay particle size in aqueous suspensions. The technique also is simple, rapid, and low-cost. Copyright © 2015 Elsevier Inc. All rights reserved.

Interferon-gamma release assay for the diagnosis of latent tuberculosis infection: A latent-class analysis.

Directory of Open Access Journals (Sweden)

Tan N Doan

Full Text Available Accurate diagnosis and subsequent treatment of latent tuberculosis infection (LTBI is essential for TB elimination. However, the absence of a gold standard test for diagnosing LTBI makes assessment of the true prevalence of LTBI and the accuracy of diagnostic tests challenging. Bayesian latent class models can be used to make inferences about disease prevalence and the sensitivity and specificity of diagnostic tests using data on the concordance between tests. We performed the largest meta-analysis to date aiming to evaluate the performance of tuberculin skin test (TST and interferon-gamma release assays (IGRAs for LTBI diagnosis in various patient populations using Bayesian latent class modelling.Systematic search of PubMeb, Embase and African Index Medicus was conducted without date and language restrictions on September 11, 2017 to identify studies that compared the performance of TST and IGRAs for LTBI diagnosis. Two IGRA methods were considered: QuantiFERON-TB Gold In Tube (QFT-GIT and T-SPOT.TB. Studies were included if they reported 2x2 agreement data between TST and QFT-GIT or T-SPOT.TB. A Bayesian latent class model was developed to estimate the sensitivity and specificity of TST and IGRAs in various populations, including immune-competent adults, immune-compromised adults and children. A TST cut-off value of 10 mm was used for immune-competent subjects and 5 mm for immune-compromised individuals.A total of 157 studies were included in the analysis. In immune-competent adults, the sensitivity of TST and QFT-GIT were estimated to be 84% (95% credible interval [CrI] 82-85% and 52% (50-53%, respectively. The specificity of QFT-GIT was 97% (96-97% in non-BCG-vaccinated and 93% (92-94% in BCG-vaccinated immune-competent adults. The estimated figures for TST were 100% (99-100% and 79% (76-82%, respectively. T-SPOT.TB has comparable specificity (97% for both tests and better sensitivity (68% versus 52% than QFT-GIT in immune-competent adults

Rheological properties of purified illite clays in glycerol/water suspensions

Science.gov (United States)

Dusenkova, I.; Malers, J.; Berzina-Cimdina, L.

2015-04-01

There are many studies about rheological properties of clay-water suspensions, but no published investigations about clay-glycerol suspensions. In this work apparent viscosity of previously purified illite containing clay fraction clay minerals were almost totally removed by centrifugation. All obtained suspensions behaved as shear-thinning fluids with multiple times higher viscosity than pure glycerol/water solutions. Reduction of clay fraction concentration by 5% decreased the apparent viscosity of 50% glycerol/water suspensions approximately 5 times. There was basically no difference in apparent viscosity between all four 50% glycerol/water suspensions, but in 90% glycerol/water suspensions samples from Iecava deposit showed slightly higher apparent viscosity, which could be affected by the particle size distribution.

Preview based control of suspension systems for commercial vehicles

NARCIS (Netherlands)

Muijderman, J.H.E.A.; Kok, J.J.; Huisman, R.G.M.; Veldpaus, F.E.; van Heck, J.G.A.M.

1999-01-01

An active suspension with preview is developed for the rear axle of a commercial vehicle. The obtained improvements are promising and justify further investigation of the more feasible semi-active suspensions with preview. The inherent non-linearity of semi-active suspensions with switching shock

Research on Dynamic Optimization for Road-friendly Vehicle Suspension

Directory of Open Access Journals (Sweden)

Lu Yongjie

2014-10-01

Full Text Available The heavy vehicle brings large dynamic loads to the road surface, which would reduce vehicle ride comfort and shorten road service life. The structure characteristic of heavy vehicle suspension has a significant impact on vehicle performance. Based on the D'Alembert principle, the dynamics models of independent and integral balanced suspension are proposed considering mass and inertia of balancing rod. The sprung mass acceleration and the tire dynamic force for two kinds of balanced suspension and the traditional quarter vehicle model are compared in frequency-domain and time-domain respectively. It is concluded that a quarter vehicle model simplified for balanced suspension could be used to evaluate the ride comfort of vehicle well, but it has some limitations in assessing the vehicle road-friendliness. Then, the sprung mass acceleration and the road damage coefficients are also analyzed under different vehicle design and running parameters at detail. Some conclusions are obtained: low suspension stiffness, high suspension damping and low tire stiffness are all favorable to improve vehicle performance; there is a saturation range of suspension damping enhancing vehicle performance; improving the road surface roughness and avoiding the no-load running are two effective methods to accomplish the better ride comfort and road-friendliness. The suspension stiffness and damping parameters are chosen for optimal parameters matching of road friendliness based on the approximation optimization method.

Interferon Gamma-Based Detection of Latent Tuberculosis Infection in the Border States of Nuevo Leon and Tamaulipas, Mexico.

Science.gov (United States)

Oren, Eyal; Alatorre-Izaguirre, Gabriela; Vargas-Villarreal, Javier; Moreno-Treviño, Maria Guadalupe; Garcialuna-Martinez, Javier; Gonzalez-Salazar, Francisco

2015-01-01

Nearly one-third of the world's population is infected with latent tuberculosis (LTBI). Tuberculosis (TB) rates in the border states are higher than national rates in both the US and Mexico, with the border accounting for 30% of total registered TB cases in both countries. However, LTBI rates in the general population in Mexican border states are unknown. In this region, LTBI is diagnosed using the tuberculin skin test (TST). New methods of detection more specific than TST have been developed, although there is currently no gold standard for LTBI detection. Our objective is to demonstrate utility of the Quantiferon TB gold In-Tube (QFT-GIT) test compared with the TST to detect LTBI among border populations. This is an observational, cross-sectional study carried out in border areas of the states of Nuevo Leon and Tamaulipas, Mexico. Participants (n = 210) provided a TST and blood sample for the QFT-GIT. Kappa coefficients assessed the agreement between TST and QFT-GIT. Participant characteristics were compared using Fisher exact tests. Thirty-eight percent of participants were diagnosed with LTBI by QFT-GIT. The proportion of LTBI detected using QFT-GIT was almost double [38% (79/210)] that found by TST [19% (39/210)] (P < 0.001). Concordance between TST and QFT-GIT was low (kappa = 0.37). We recommend further studies utilizing the QFT-GIT test to detect LTBI among border populations.

Numerical study of suspensions of deformable particles.

Science.gov (United States)

Brandt, Luca; Rosti, Marco Edoardo

2017-11-01

We consider a model non-Newtonian fluid consisting of a suspension of deformable particles in a Newtonian solvent. Einstein showed in his pioneering work that the relative increase in effective viscosity is a linear function of the particle volume fraction for dilute suspensions of rigid particles. Inertia has been shown to introduce deviations from the behaviour predicted by the different empirical fits, an effect that can be related to an increase of the effective volume fraction. We here focus on the effect of elasticity, i.e. visco-elastic deformable particles. To tackle the problem at hand, we perform three-dimensional Direct Numerical Simulation of a plane Couette flow with a suspension of neutrally buoyant deformable viscous hyper-elastic particles. We show that elasticity produces a shear-thinning effect in elastic suspensions (in comparison to rigid ones) and that it can be understood in terms of a reduction of the effective volume fraction of the suspension. The deformation modifies the particle motion reducing the level of mutual interaction. Normal stress differences will also be considered. European Research Council, Grant No. ERC-2013-CoG- 616186, TRITOS; SNIC (the Swedish National Infrastructure for Computing).

Minimally invasive brow suspension for facial paralysis.

Science.gov (United States)

Costantino, Peter D; Hiltzik, David H; Moche, Jason; Preminger, Aviva

2003-01-01

To report a new technique for unilateral brow suspension for facial paralysis that is minimally invasive, limits supraciliary scar formation, does not require specialized endoscopic equipment or expertise, and has proved to be equal to direct brow suspension in durability and symmetry. Retrospective survey of a case series of 23 patients between January 1997 and December 2000. Metropolitan tertiary care center. Patients with head and neck tumors and brow ptosis caused by facial nerve paralysis. The results of the procedure were determined using the following 3-tier rating system: outstanding (excellent elevation and symmetry); acceptable (good elevation and fair symmetry); and unacceptable (loss of elevation). The results were considered outstanding in 12 patients, acceptable in 9 patients, and unacceptable in only 1 patient. One patient developed a hematoma, and 1 patient required a secondary adjustment. The technique has proved to be superior to standard brow suspension procedures with regard to scar formation and equal with respect to facial symmetry and suspension. These results have caused us to abandon direct brow suspension and to use this minimally invasive method in all cases of brow ptosis due to facial paralysis.

Effect of body-weight suspension training versus treadmill training on gross motor abilities of children with spastic diplegic cerebral palsy.

Science.gov (United States)

Emara, Hatem A; El-Gohary, Tarek M; Al-Johany, Ahmed A

2016-06-01

Suspension training and treadmill training are commonly used for promoting functional gross motor skills in children with cerebral palsy. The aim of this study was to compare the effect of body-weight suspension training versus treadmill training on gross motor functional skills. Assessor-blinded, randomized, controlled intervention study. Outpatient rehabilitation facility. Twenty children with spastic diplegia (7 boys and 13 girls) in the age ranged from 6 to 8 years old were randomly allocated into two equal groups. All children were assessed at baseline, after 18-session and after 36-session. During the twelve-week outpatient rehabilitation program, both groups received traditional therapeutic exercises. Additionally, one group received locomotor training using the treadmill while the other group received locomotor training using body-weight suspension through the dynamic spider cage. Assessment included dimensions "D" standing and "E" walking of the gross motor function measure, in addition to the 10-m Walking Test and the five times sit to stand test. Training was applied three times per week for twelve consecutive weeks. No significant difference was found in standing or walking ability for measurements taken at baseline or after 18-session of therapy. Measurements taken at 36-session showed that suspension training achieved significantly (Ptraining for dimension D as well as for dimension E. No significant difference was found between suspension training and treadmill training regarding walking speed or sit to stand transitional skills. Body-weight suspension training is effective in improving walking and locomotor capabilities in children with spastic diplegia. After three month suspension training was superior to treadmill training. Body-weight suspension training promotes adequate postural stability, good balance control, and less exertion which facilitates efficient and safe gait.

Toward a general psychological model of tension and suspense.

Science.gov (United States)

Lehne, Moritz; Koelsch, Stefan

2015-01-01

Tension and suspense are powerful emotional experiences that occur in a wide variety of contexts (e.g., in music, film, literature, and everyday life). The omnipresence of tension and suspense suggests that they build on very basic cognitive and affective mechanisms. However, the psychological underpinnings of tension experiences remain largely unexplained, and tension and suspense are rarely discussed from a general, domain-independent perspective. In this paper, we argue that tension experiences in different contexts (e.g., musical tension or suspense in a movie) build on the same underlying psychological processes. We discuss key components of tension experiences and propose a domain-independent model of tension and suspense. According to this model, tension experiences originate from states of conflict, instability, dissonance, or uncertainty that trigger predictive processes directed at future events of emotional significance. We also discuss possible neural mechanisms underlying tension and suspense. The model provides a theoretical framework that can inform future empirical research on tension phenomena.

Shear-induced changes of electrical conductivity in suspensions

Energy Technology Data Exchange (ETDEWEB)

Crawshaw, John; Meeten, Gerald [Schlumberger Cambridge Research, Cambridge (United Kingdom)

2006-12-15

The effect of shear on electrical conductivity (rheo-conduction) is studied to give information about particle behaviour in suspensions. Past work is reviewed, and expressions are derived for the rheo-conduction of a suspension of nonconducting spheroids in a conducting matrix for current flow, parallel and normal to the suspension flow direction. A simple apparatus to study rheo-conduction in pipe flow is described, and measurements of steady and time-dependent effects are reported for various suspensions of colloidal particles. Suspensions of anisometric rod- and platelike particles at low concentrations showed rheo-conductive changes of sign, magnitude and relaxation that were consistent with the particle shape, concentration and interactions. The rheo-conductive response decreased with increasing volume fraction for platelike kaolinite particles, attributed to orientational jamming. Spherical latex particles gave unexpected rheo-conductive changes consistent with shear disruption of a conductive network of particles. It is concluded that rheo-conduction measurements are a useful adjunct to conventional rheometry. (orig.)

15 CFR 2011.207 - Suspension of the certificate system.

Science.gov (United States)

2010-01-01

..., SYRUPS AND MOLASSES Specialty Sugar § 2011.207 Suspension of the certificate system. (a) Suspension. The.... Notice of such suspension and the effective date thereof shall be published in the Federal Register. (b... such reinstatement and the effective date thereof shall be published in the Federal Register. (c...

A new pneumatic suspension system with independent stiffness and ride height tuning capabilities

Science.gov (United States)

Yin, Zhihong; Khajepour, Amir; Cao, Dongpu; Ebrahimi, Babak; Guo, Konghui

2012-12-01

This paper introduces a new pneumatic spring for vehicle suspension systems, allowing independent tuning of stiffness and ride height according to different vehicle operating conditions and driver preferences. The proposed pneumatic spring comprises a double-acting pneumatic cylinder, two accumulators and a tuning subsystem. This paper presents a detailed description of the pneumatic spring and its working principle. The mathematical model is established based on principles of thermo and fluid dynamics. An experimental setup has been designed and fabricated for testing and evaluating the proposed pneumatic spring. The analytical and experimental results confirm the capability of the new pneumatic spring system for independent tuning of stiffness and ride height. The mathematical model is verified and the capabilities of the pneumatic spring are further proved. It is concluded that this new pneumatic spring provides a more flexible suspension design alternative for meeting various conflicting suspension requirements for ride comfort and performance.

Optimal Vibration Control for Tracked Vehicle Suspension Systems

Directory of Open Access Journals (Sweden)

Yan-Jun Liang

2013-01-01

Full Text Available Technique of optimal vibration control with exponential decay rate and simulation for vehicle active suspension systems is developed. Mechanical model and dynamic system for a class of tracked vehicle suspension vibration control is established and the corresponding system of state space form is described. In order to prolong the working life of suspension system and improve ride comfort, based on the active suspension vibration control devices and using optimal control approach, an optimal vibration controller with exponential decay rate is designed. Numerical simulations are carried out, and the control effects of the ordinary optimal controller and the proposed controller are compared. Numerical simulation results illustrate the effectiveness of the proposed technique.

Challenging an immediate suspension of a DEA registration: is it time for a new tact?

Science.gov (United States)

Behr, Douglas J

2014-01-01

A Drug Enforcement Administration ("DEA") registration is not only a necessity, but also an invaluable commodity for doctors, pharmacists, hospitals and drug wholesalers who prescribe, stock, and distribute controlled substances. While the DEA may only suspend a registration by issuing an immediate suspension order ("ISO) after an ex parte finding of "imminent danger to the public health or safety," the law fails to explicitly protect the registrant by way of a post-suspension hearing on the ISO, despite the registrant's constitutionally protected property interest in the registration. A registrant has only two procedural options--which are often unsuccessful--to challenge the ISO: endure a long and arduous administrative review proceeding or petition the court for a "not-so-easily proven" injunction, all the while the suspension remains in effect and the controlled substance business operations cease. Accordingly, a suspension of the registration may be certain death to doctors and pharmacists without the financial means to operate the business in the absence of the registration. Because the DEA registration is a constitutionally-protected interest, there is a better way to challenge the suspension. The Supreme Court has held that once a license is issued, the continued possession of it is essential to the registrant's livelihood. Therefore suspension or revocation of such a protected interest requires due process. Due-process hearings, while varied, will provide the necessary avenues of review to provide a fair review of the justification of the suspension and its continuance, i.e., whether there truly is imminent danger to public health or safety and whether the suspension is overbroad and should be limited. To date, this thesis remains to be tested and awaits a petitioner with a justiciable claim and the financial resources to challenge the DEA in court. But in the field of DEA ISO challenges, it is time for a new tact!

Nanometer-scale sizing accuracy of particle suspensions on an unmodified cell phone using elastic light scattering.

Directory of Open Access Journals (Sweden)

Zachary J Smith

Full Text Available We report on the construction of a Fourier plane imaging system attached to a cell phone. By illuminating particle suspensions with a collimated beam from an inexpensive diode laser, angularly resolved scattering patterns are imaged by the phone's camera. Analyzing these patterns with Mie theory results in predictions of size distributions of the particles in suspension. Despite using consumer grade electronics, we extracted size distributions of sphere suspensions with better than 20 nm accuracy in determining the mean size. We also show results from milk, yeast, and blood cells. Performing these measurements on a portable device presents opportunities for field-testing of food quality, process monitoring, and medical diagnosis.

Heat and mass transfer in particulate suspensions

CERN Document Server

Michaelides, Efstathios E (Stathis)

2013-01-01

Heat and Mass Transfer in Particulate Suspensions is a critical review of the subject of heat and mass transfer related to particulate Suspensions, which include both fluid-particles and fluid-droplet Suspensions. Fundamentals, recent advances and industrial applications are examined. The subject of particulate heat and mass transfer is currently driven by two significant applications: energy transformations –primarily combustion – and heat transfer equipment. The first includes particle and droplet combustion processes in engineering Suspensions as diverse as the Fluidized Bed Reactors (FBR’s) and Internal Combustion Engines (ICE’s). On the heat transfer side, cooling with nanofluids, which include nanoparticles, has attracted a great deal of attention in the last decade both from the fundamental and the applied side and has produced several scientific publications. A monograph that combines the fundamentals of heat transfer with particulates as well as the modern applications of the subject would be...

Correlation between tuberculin skin test and IGRAs with risk factors for the spread of infection in close contacts with sputum smear positive in pulmonary tuberculosis.

Science.gov (United States)

de Souza-Galvão, Maria Luiza; Latorre, Irene; Altet-Gómez, Neus; Jiménez-Fuentes, María Ángeles; Milà, Celia; Solsona, Jordi; Seminario, Maria Asunción; Cantos, Adela; Ruiz-Manzano, Juan; Domínguez, José

2014-05-13

The aim of the study was to assess the correlation between the tuberculin skin test (TST) and in vitro interferon-gamma released assays (IGRAs) with risk factors for the spread of infection in smear positive pulmonary tuberculosis (TB) contacts. We recruited prospective contacts with smear positive pulmonary TB cases. We looked at human immunodeficiency virus (HIV) infection and other conditions of immunosuppression, presence of BCG vaccination and the degree of exposure to the index case. Patients underwent the TST, chest radiography, sputum analysis when necessary, and IGRA assays (QFN-G-IT and T-SPOT.TB). Presence of cough, diagnostic delay (days between first symptoms and TB diagnostic), contact conditions: room size (square meters) and index of overcrowding (square meters per person) were investigated in the index case. 156 contacts (119 adults, 37 children) of 66 TB patients were enrolled, 2.4 (1-14) contacts per TB case. The positivity of the TST did not correlate with the risk factors studied: presence of cough (p = 0.929); delayed diagnosis (p = 0.244); room size (p = 0.462); overcrowding (p = 0.800). Both QFN-G-IT and T-SPOT.TB, showed significant association with cough (p = 0.001, and p = 0.007) and room size (p = 0.020, and p = 0.023), respectively. Both IGRA associated better than TST with certain host-related risk factors involved in the transmission of disease, such as the presence of cough.

Recent Developments in Suspension Plasma Sprayed Titanium Oxide and Hydroxyapatite Coatings

Science.gov (United States)

Jaworski, R.; Pawlowski, L.; Pierlot, C.; Roudet, F.; Kozerski, S.; Petit, F.

2010-01-01

The paper aims at reviewing of the recent studies related to the development of suspension plasma sprayed TiO2 and Ca5(PO4)3OH (hydroxyapatite, HA) coatings as well as their multilayer composites obtained onto stainless steel, titanium and aluminum substrates. The total thickness of the coatings was in the range 10 to 150 μm. The suspensions on the base of distilled water, ethanol and their mixtures were formulated with the use of fine commercial TiO2 pigment crystallized as rutile and HA milled from commercial spray-dried powder or synthesized from calcium nitrate and ammonium phosphate in an optimized reaction. The powder was crystallized as hydroxyapatite. Pneumatic and peristaltic pump liquid feeders were applied. The injection of suspension to the plasma jet was studied carefully with the use of an atomizer injector or a continuous stream one. The injectors were placed outside or inside of the anode-nozzle of the SG-100 plasma torch. The stream of liquid was tested under angle right or slightly backwards with regard to the torch axis. The sprayed deposits were submitted to the phase analysis by the use of x-ray diffraction. The content of anatase and rutile was calculated in the titanium oxide deposits as well as the content of the decomposition phases in the hydroxyapatite ones. The micro-Raman spectroscopy was used to visualize the area of appearance of some phases. Scratch test enabled to characterize the adhesion of the deposits, their microhardness and friction coefficient. The electric properties including electron emission, impedance spectroscopy, and dielectric properties of some coatings were equally tested.

Effects of Mimosa pudica L. leaves extract on anxiety, depression and memory

Directory of Open Access Journals (Sweden)

Ganesh Patro

2016-11-01

Full Text Available Objective: The present study was carried out to investigate the neuropharmacological activities of ethyl acetate extract of Mimosa pudica (EAMP leaves on anxiety, depression and memory in a mouse model. Materials and Methods: Anti-anxiety potential of EAMP was evaluated by elevated plus maze (EPM, light-dark box (LDB and social interaction (SI tests in mice.Anti-depressant potential of EAMP was evaluated by forced swimming (FST, tail suspension (TST, and open field tests (OFT. The behavioral findings were further corroborated with estimation of neurotransmitters and their metabolites from mouse brain homogenate. Effect on learning and memory was evaluated by EPM, passive avoidance (PA tests. Further, it was confirmed with assessment of acetylcholinesterase and caspase-3 activity in brain homogenate. Results: EAMP showed significant anti-anxiety activity by increasing the time spent in open arm of EPM, light box of LDB. Social interaction time was increased significantly (p

Specificity of the Tuberculin Skin Test and the T-SPOT."TB" Assay among Students in a Low-Tuberculosis Incidence Setting

Science.gov (United States)

Talbot, Elizabeth A.; Harland, Dawn; Wieland-Alter, Wendy; Burrer, Sherry; Adams, Lisa V.

2012-01-01

Objective: Interferon-[gamma] release assays (IGRAs) are an important tool for detecting latent "Mycobacterium tuberculosis" infection (LTBI). Insufficient data exist about IGRA specificity in college health centers, most of which screen students for LTBI using the tuberculin skin test (TST). Participants: Students at a low-TB incidence college…

Bidisperse and polydisperse suspension rheology at large solid fraction

Energy Technology Data Exchange (ETDEWEB)

Pednekar, Sidhant [Benjamin Levich Institute and Department of Chemical Engineering, The City College of New York, New York, New York 10031; Chun, Jaehun [Pacific Northwest National Laboratory, Richland, Washington 99352; Morris, Jeffrey F. [Benjamin Levich Institute and Department of Chemical Engineering, The City College of New York, New York, New York 10031

2018-03-01

At the same solid volume fraction, bidisperse and polydisperse suspensions display lower viscosities, and weaker normal stress response, compared to monodisperse suspensions. The reduction of viscosity associated with size distribution can be explained by an increase of the maximum flowable, or jamming, solid fraction. In this work, concentrated or "dense" suspensions are simulated under strong shearing, where thermal motion and repulsive forces are negligible, but we allow for particle contact with a mild frictional interaction with interparticle friction coefficient of 0.2. Aspects of bidisperse suspension rheology are first revisited to establish that the approach reproduces established trends; the study of bidisperse suspensions at size ratios of large to small particle radii (2 to 4) shows that a minimum in the viscosity occurs for zeta slightly above 0.5, where zeta=phi_{large}/phi is the fraction of the total solid volume occupied by the large particles. The simple shear flows of polydisperse suspensions with truncated normal and log normal size distributions, and bidisperse suspensions which are statistically equivalent with these polydisperse cases up to third moment of the size distribution, are simulated and the rheologies are extracted. Prior work shows that such distributions with equivalent low-order moments have similar phi_{m}, and the rheological behaviors of normal, log normal and bidisperse cases are shown to be in close agreement for a wide range of standard deviation in particle size, with standard correlations which are functionally dependent on phi/phi_{m} providing excellent agreement with the rheology found in simulation. The close agreement of both viscosity and normal stress response between bi- and polydisperse suspensions demonstrates the controlling in influence of the maximum packing fraction in noncolloidal suspensions. Microstructural investigations and the stress distribution according to particle size are also presented.

Lattice Boltzmann methods for the simulation of heat transfer in particle suspensions

International Nuclear Information System (INIS)

McCullough, J.W.S.; Leonardi, C.R.; Jones, B.D.; Aminossadati, S.M.; Williams, J.R.

2016-01-01

Highlights: • Development of a lattice Boltzmann heat transfer model for curved boundaries. • Thermodynamic coupling aims to ensure continuity of both temperature and heat flux. • Good correlation found in transient comparison of results to analytical solutions. • Illustration of the developed model applied to a moving particle test case. - Abstract: This study examines the use of a lattice Boltzmann method framework to study heat transfer behaviours within particle suspensions. This has been done through the use of an adapted interface condition to attempt to resolve the required continuity of temperature and flux at the boundary between the solid and fluid phases. The proposed method is tested against analytical solutions for layered media in both a 1D bar and a radial layout. These tests showed that the model was able to generate results with first order convergence towards the analytical outcomes. The model was then used to examine the behaviour of two moving particles travelling along a channel to illustrate its potential for resolving complex suspension flows.

Effect of suspension systems on the physiological and psychological responses to sub-maximal biking on simulated smoothand bumpy tracks.

Science.gov (United States)

Titlestad, John; Fairlie-Clarke, Tony; Whittaker, Arthur; Davie, Mark; Watt, Ian; Grant, Stanley

2006-02-01

The aim of this study was to compare the physiological and psychological responses of cyclists riding on a hard tail bicycle and on a full suspension bicycle. Twenty males participated in two series of tests. A test rig held the front axle of the bicycle steady while the rear wheel rotated against a heavy roller with bumps (or no bumps) on its surface. In the first series of tests, eight participants (age 19-27 years, body mass 65-82 kg) were tested on both the full suspension and hard tail bicycles with and without bumps fitted to the roller. The second series of test repeated the bump tests with a further six participants (age 22-31 years, body mass 74-94 kg) and also involved an investigation of familiarization effects with the final six participants (age 21-30 years, body mass 64-80 kg). Heart rate, oxygen consumption (VO(2)), rating of perceived exertion (RPE) and comfort were recorded during 10 min sub-maximal tests. Combined data for the bumps tests show that the full suspension bicycle was significantly different (P < 0.001) from the hard tail bicycle on all four measures. Oxygen consumption, heart rate and RPE were lower on average by 8.7 (s = 3.6) ml . kg(-1) . min(-1), 32.1 (s = 12.1) beats . min(-1) and 2.6 (s = 2.0) units, respectively. Comfort scores were higher (better) on average by 1.9 (s = 0.8) units. For the no bumps tests, the only statistically significant difference (P = 0.008) was in VO(2), which was lower for the hard tail bicycle by 2.2 (s = 1.7) ml . kg(-1) . min(-1). The results indicate that the full suspension bicycle provides a physiological and psychological advantage over the hard tail bicycle during simulated sub-maximal exercise on bumps.

Energy Conservation Analysis and Control of Hybrid Active Semiactive Suspension with Three Regulating Damping Levels

Directory of Open Access Journals (Sweden)

Long Chen

2016-01-01

Full Text Available Active suspension has not been popularized for high energy consumption. To address this issue, this paper introduces the concept of a new kind of suspension. The linear motor is considered to be integrated into an adjustable shock absorber to form the hybrid active semiactive suspension (HASAS. To realize the superiority of HASAS, its energy consumption and regeneration mechanisms are revealed. And the system controller which is composed of linear quadratic regulator (LQR controller, mode decision and switch controller, and the sliding mode control based thrust controller is developed. LQR controller is designed to maintain the suspension control objectives, while mode decision and switch controller decides the optimal damping level to tune motor thrust. The thrust controller ensures motor thrust tracking. An adjustable shock absorber with three regulating levels to be used in HASAS is trial produced and tested to obtain its working characteristics. Finally, simulation analysis is made with the experimental three damping characteristics. The impacts of adjustable damping on the motor force and energy consumption are investigated. Simulation results demonstrate the advantages of HASAS in energy conservation with various suspension control objectives. Even self-powered active control and energy regenerated to the power source can be realized.

Evaluation of antidepressant like activity of curcumin and its combination with fluoxetine and imipramine: an acute and chronic study.

Science.gov (United States)

Sanmukhani, Jayesh; Anovadiya, Ashish; Tripathi, Chandrabhanu B

2011-01-01

Curcumin is the active ingredient of commonly used spice Curuma longa Linn. In the present study, the antidepressant like activity of curcumin and its combination with fluoxetine and imipramine was studied in acute model (three doses 24, 5 and 1 h before test) of forced swimming test (FST) in glass jar and tail suspension test (TST) in mice and in chronic model (14 day study) of FST with water wheel in rats. All the tests were carried out in the following seven groups (n = 6 in each group), drugs being given orally (doses for mice): Group 1 (vehicle), group 2 (curcumin 50 mg/kg), group 3 (curcumin 100 mg/kg), group 4 (fluoxetine 20 mg/kg), group 5 (imipramine 15 mg/kg), group 6 (curcumin 100 mg/kg plus fluoxetine 20 mg/kg) and group 7 (curcumin 100 mg/kg plus imipramine 15 mg/kg). Equivalent doses for rats were used. Both the acute model of FST and TST, and the chronic model of FST with water wheel showed significant antidepressant like activity of curcumin in 100 mg/kg dose as compared to vehicle control (p fluoxetine and imipramine (p > 0.05) but its addition to fluoxetine and imipramine did not improve their antidepressant activity (p > 0.05). Curcumin increased both the swimming and climbing behavior in FST, thus its antidepressant like activity could be due to an increase in serotonin, norepinephrine and dopamine levels in the brain. Curcumin can be a useful antidepressant especially in cases which respond to drugs having mixed effects on serotonin and catecholamines levels in the brain.

Correlation between structure and rheological properties of suspension of nanosized powders

Energy Technology Data Exchange (ETDEWEB)

Tabellion, J.; Clasen, R. [Saarland Univ., Saarbruecken (Germany). Dept. of Powder Technology; Reinshagen, J.; Oberacker, R.; Hoffmann, M.J. [Karlsruhe Univ. (Germany). Inst. for Ceramics in Mechanical Engineering

2002-07-01

Since the properties of a ceramic green body and compact produced thereof are strongly influenced by the properties of the suspension used, controlling structure and properties of a suspension is a very important issue in ceramic manufacturing. Macroscopically, the rheological properties of a suspension are the key parameters that influence the behaviour during the shaping process. The rheological behaviour of aqueous suspensions of nanosized fumed silica (DEGUSSA, Aerosil OX50) with different amounts of OX50 (10 to 50 wt.%) was measured over a pH-range from 1 to 13 by means of rotational viscosimetry. A distinct maximum of the viscosity was observed for a pH of about 7 to 8, independent of the solid content of the suspensions. Since the rheological behaviour of the suspensions could not be explained by the {zeta}-Potential measured for OX50, the suspensions were investigated by means of so-called cryo-SEM characterization. A droplet of the suspension is quench-frozen in subcooled nitrogen (-210 C), prepared and the water is sublimed at -90 C. Thus it was possible to visualize the agglomerate structure of the primary OX50-particles within the suspensions. (orig.)

3D modeling design and engineering analysis of automotive suspension beam

Directory of Open Access Journals (Sweden)

Ju Zhi Lan

2016-01-01

Full Text Available Automotive suspension is an important device for transmission and torque. The main parameters and dimensions of 40 tons of heavy duty truck spring suspension system are designed in the paper. According to the data, the 3D modeling and virtual assembly of the leaf spring suspension are carried out by using parametric design. Structural stress of spring suspension is analyzed which can provide a guide and basis for the design of the leaf spring suspension.

Determination of residual 4'-aminomethyl-4,5',8-trimethylpsoralen and mutagenicity testing following psoralen plus UVA treatment of platelet suspensions

Energy Technology Data Exchange (ETDEWEB)

Wagner, S.J.; Robinette, D.; Dodd, R.Y. (American Red Cross Blood Services, Rockville, MD (United States). Jerome H. Holland Lab. for Biomedical Sciences); White, R.; Wolf, L.; Chapman, J. (Baxter Biotech, Round Lake, IL (United States). Fenwal Labs.); Lawlor, T.E. (Hazleton Labs., Vienna, VA (United States). Molecular and Cellular Toxicology)

1993-05-01

Psoralens and UVa light have been used in the laboratory to study the inactivation of viruses that may be infrequently present in platelet concentrates prepared for transfusion. In order to evaluate safety aspects of the treatment of platelet suspensions with 4'-aminomethyl-4,5'8-trimethylpsoralen (AMT), the authors have investigated the residual levels and mutagenic potential of AMT after UVA phototreatment. The results suggest that residual available AMT is mutagenic in the AMES test and that the observed frameshift mutations may be caused by binding of AMt or its metabolites to nucleic acids in the absence of UVA light. (Author).

Phagocytosis in phosphate chromium (III) suspensions

International Nuclear Information System (INIS)

Cruz-Arencibia, Jorge; Fano Machín, Yoiz; Cruz-Morales, Ahmed; Tamayo Fuente, Radamés; Morín-Zorrilla, José

2015-01-01

Phagocytosis in vivo and in vitro of a suspension of chromic phosphate (III) labeled with 51 Cr and 32 P is studied. The radioactive particles dispersed in a media of 2 % gelatin in acetate buffer pH 4-4.5 have a predominant size of 0.8 μm and 5 μm. According with biodistribution experiments in rats after 30 minutes near the 80 % of radioactivity is registered in the liver, probably associated with phagocytosis of the particles by liver Kupffer cells. Is also showed that the suspension particles are phagocytized in vitro by mouse peritoneal macrophages. This facts indicate that the studied suspension have appropriate characteristics to be used in radiosynoviorthesis according to the principal action mechanism described for this procedure, particles phagocytosis by cells present in the inflamed synovium. (author)

Crust formation in drying colloidal suspensions

KAUST Repository

Style, R. W.

2010-06-30

During the drying of colloidal suspensions, the desiccation process causes the suspension near the air interface to consolidate into a connected porous matrix or crust. Fluid transport in the porous medium is governed by Darcy\\'s law and the equations of poroelasticity, while the equations of colloid physics govern processes in the suspension. We derive new equations describing this process, including unique boundary conditions coupling the two regions, yielding a moving-boundary model of the concentration and stress profiles during drying. A solution is found for the steady-state growth of a nedimensional crust during constant evaporation rate from the surface. The solution is used to demonstrate the importance of the system boundary conditions on stress profiles and diffusivity in a drying crust. © 2011 The Royal Society.

Comparative Evaluation of Antifungal Activity of Piper Betel Leaf Oil, Origanum vulgare Essential Oil and Fluconazole Suspension on Candida albicans − An In Vitro Study

Directory of Open Access Journals (Sweden)

Nisha Makkar

2017-01-01

Full Text Available Introduction: Oropharyngeal candidiasis is an opportunistic mucosal infection caused by Candida albicans. It usually responds to topical treatments such as clotrimazole troches, topical fluconazole, chlorhexidine mouthwash and nystatin suspension. Piper betel leaf oil and Origanum vulgare essential oil have shown some topical antifungal activity. Aim: To determine and compare the antifungal efficacy of piper betel leaf oil, O. vulgare essential oil and fluconazole suspension against C. albicans. Materials and Methods: The zone of inhibition was measured by the cup–plate diffusion method using 100 μl volume of piper betel leaf oil, O. vulgare essential oil and fluconazole suspension, which were pipetted into the wells of the inoculated Sabouraud’s dextrose agar plates. The zone of inhibition was measured in millimetres using Vernier calliper. Minimum inhibitory concentration (MIC was determined by the broth macro-dilution test by pouring 1 ml of the respective concentrations of the test material to the individual test tubes along with 10 μl of the diluted test organism inoculum. Finally, MIC was calculated using a reflective viewer. Results: The zone of inhibition for O. vulgare essential oil (>40 mm was more than fluconazole suspension (>35 mm. MIC of O. vulgare essential oil, piper betel leaf oil and fluconazole suspension was 1.6%, 0.4% and 0.8%, respectively. Conclusion: O. vulgare essential oil was found to be a more effective antifungal agent than piper betel leaf oil and fluconazole suspension.

15 CFR 14.13 - Debarment and suspension.

Science.gov (United States)

2010-01-01

... 15 Commerce and Foreign Trade 1 2010-01-01 2010-01-01 false Debarment and suspension. 14.13 Section 14.13 Commerce and Foreign Trade Office of the Secretary of Commerce UNIFORM ADMINISTRATIVE... shall comply with the nonprocurement debarment and suspension common rule implementing E.O.s 12549 and...

19 CFR 210.23 - Suspension of investigation.

Science.gov (United States)

2010-04-01

... 19 Customs Duties 3 2010-04-01 2010-04-01 false Suspension of investigation. 210.23 Section 210.23 Customs Duties UNITED STATES INTERNATIONAL TRADE COMMISSION INVESTIGATIONS OF UNFAIR PRACTICES IN IMPORT TRADE ADJUDICATION AND ENFORCEMENT Motions § 210.23 Suspension of investigation. Any party may move to...

Active Control of Suspension Bridges

DEFF Research Database (Denmark)

Thoft-Christensen, Palle

In this paper some recent research on active control of very long suspension bridges, is presented. The presentation is based on research work at Aalborg University, Denmark. The active control system is based on movable flaps attached to the bridge girder. Wind load on bridges with or without...... flaps attached to the girder is briefly presented. A simple active control system is discussed. Results from wind tunnel experiments with a bridge section show that flaps can be used effectively to control bridge girder vibrations. Flutter conditions for suspension bridges with and without flaps...

Feasibility Study for Implementing Magnetic Suspension in the Glenn Research Center 225 cm2 Supersonic Wind Tunnel for Testing the Dynamic Stability of Blunt Bodies

Science.gov (United States)

Sevier, Abigail; Davis, David O.; Schoenenberger, Mark; Barnhart, Paul

2016-01-01

The implementation of a magnetic suspension system in the NASA Glenn Research Center (GRC) 225 cm2 Supersonic Wind Tunnel would be a powerful test technique that could accurately determine the dynamic stability of blunt body entry vehicles with no sting interference. This paper explores initial design challenges to be evaluated before implementation, including defining the lowest possible operating dynamic pressure and corresponding model size, developing a compatible video analysis technique, and incorporating a retractable initial support sting.

On reactive suspension plasma spraying of calcium titanate

OpenAIRE

Kotlan, J. (Jiří); Pala, Z. (Zdeněk); Mušálek, R. (Radek); Ctibor, P. (Pavel)

2016-01-01

This study shows possibility of preparation of calcium titanate powder and coatings by reactive suspension plasma spraying. Suspension of mixture of calcium carbonate (CaCO3) and titanium dioxide (TiO2) powders in ethanol was fed into hybrid plasma torch with a DC-arc stabilized by a water–argon mixture (WSP-H 500). Various feeding distances and angles were used in order to optimize suspension feeding conditions. In the next step, the coatings were deposited on stainless steel substrates and ...

Shock Absorbers Multi-Modeling and Suspension Optimization

Directory of Open Access Journals (Sweden)

LUPU Ciprian

2013-05-01

Full Text Available The standard dampers used by more 90% of vehicles have damping coefficients constant along stroke, so they can’t solve simultaneous all of them, situation solving practically using a relative dampingcoefficient able to made compromise between them. This paper design and simulation testing multi-models of two types of Damp (DSA and VZN. To compare the two types of suspension they are simulated in various road and load conditions. Analysis of simulation results is presente a new VZN shock absorber. This is an invention of the Institute of Mechanics of the Romanian Academy, and patented at European and U.S. [1], [2]. This is Called VZN shock absorber, iscoming from Variable Zeta Necessary acronym, for well moving in all road and load Conditions, Where zeta Represents the relative damping, Which is Adjusted automatically, stepwise, According to the piston positions [3,4,5]. Suspension systems are used in all air and ground transportation to protect that building transportation and cargo transported around against shocks and vibrations induced in the systemfrom the road Modifying damping coefficients (Zeta function piston position, being correlated with vehicle load and road unevenness.

Vehicle lateral dynamics stabilization using active suspension

Directory of Open Access Journals (Sweden)

Drobný V.

2008-12-01

Full Text Available The paper deals with the investigation of active nonlinear suspension control in order to stabilize the lateral vehicle motion in similar way as systems like ESP do. The lateral stabilization of vehicle based on braking forces can be alternatively provided by the different setting of suspension forces. The basis of this control is the nonlinear property of the tyres. The vehicle has at least four wheels and it gives one or more redundant vertical forces that can be used for the different distribution of vertical suspension forces in such a way that resulting lateral and/or longitudinal forces create the required correction moment for lateral dynamic vehicle stabilization.

289 Étude expérimentale hydrodynamique des suspensions non ...

African Journals Online (AJOL)

Afrique Sciences

qui modifient complètement l'hydrodynamique et la thermique de .... [11] ont étudié le stockage et de distribution du froid par chaleur latente en traitant, ... Deux types de matériaux à changement de phase ont été́testés : coulis de glace et coulis ...... Figure 7 : Evolution du coefficient de frottement des suspensions dans la ...

A magneto rheological hybrid damper for railway vehicles suspensions

Directory of Open Access Journals (Sweden)

Gheorghe GHITA

2012-09-01

Full Text Available High speed railway vehicles features a specific lateral oscillation resulting from the coupled lateral displacement and yaw of the wheelset which leads to a sinusoid movement of the wheelset along the track, transferred to the entire vehicle. The amplitude of this oscillation is strongly dependant on vehicle’s velocity. Over a certain value, namely the critical speed, the instability phenomenon so-called hunting occurs. To raise the vehicle’s critical speed different designs of the suspension all leading to a much stiffer vehicle can be envisaged. Different simulations prove that a stiffer central suspension will decrease the passenger’s comfort in terms of lateral accelerations of the carboy. The authors propose a semi-active magneto rheological suspension to improve the vehicle’s comfort at high speeds. The suspension has as executive elements hybrid magneto rheological dampers operating under sequential control strategy type balance logic. Using an original mathematical model for the lateral dynamics of the vehicle the responses of the system with passive and semi-active suspensions are simulated. It is shown that the semi-active suspension can improve the vehicle performances.

Analysis and experimental validation of an HTS linear synchronous propulsion prototype with HTS magnetic suspension

International Nuclear Information System (INIS)

Jin Jianxun; Zheng Luhai; Guo Youguang; Xu Wei; Zhu Jianguo

2011-01-01

An HTS linear synchronous propulsion prototype with an HTSLSM drive is developed. The feasibility of combining an HTSLSM with an HTS magnetic suspension system has been verified. Three different PMGs are studied by ECS method and experiment verification to obtain an optimal one. The prototype has been tested to obtain the performance and thrust characteristics of the HTSLSM. The measurement results benefit the optimal design and control scheme development for an HTSLSM. A high temperature superconducting (HTS) linear propulsion system composed of a single-sided HTS linear synchronous motor (HTSLSM) in its middle and HTS magnetic suspension sub-systems on both sides has been developed. The HTSLSM uses an HTS bulk magnet array on the moving secondary, and the field-trapped characteristics of the HTS bulk using different magnetized methods have been measured and compared to identify their magnetization capability. In order to generate a large levitation force for the system, three different types of permanent magnet guideways (PMGs) have been numerically analyzed and experimentally verified to obtain an optimal PMG. Based on comprehensive experimental prototype tests, the results show that the HTS linear propulsion system can run with stable magnetic suspension having a constant air-gap length, and the thrust characteristics versus the exciting current, working frequency and the air-gap length have also been obtained. This work forms the basis for developing a practical HTS linear propulsion system by using HTS bulks both for propulsion and suspension.

Preparation of conjugated polymer suspensions by using ultrasonic atomizer

Energy Technology Data Exchange (ETDEWEB)

Tada, Kazuya, E-mail: tada@eng.u-hyogo.ac.jp; Onoda, Mitsuyoshi

2010-11-30

The electrophoretic deposition is a method useful to prepare conjugated polymer films for electronic devices. This method provides high material recovery rate on the substrate from the suspension, in contrast to the conventional spin-coating in which most of the material placed on the substrate is blown away. Although manual reprecipitation technique successfully yields suspensions of various conjugated polymers including polyfluorene derivatives, it is favorable to control the preparation process of suspensions. In this context, this paper reports preliminary results on the preparation of suspension of conjugated polymer by using an ultrasonic atomizer. While the resultant films do not show particular difference due to the preparation methods of the suspension, the electric current profiles during the electrophoretic deposition suggests that the ultrasonic atomization of polymer solution prior to be mixed with poor solvent results in smaller and less uniform colloidal particles than the conventional manual pouring method.

45 CFR 99.4 - Suspension of rules.

Science.gov (United States)

2010-10-01

... 45 Public Welfare 1 2010-10-01 2010-10-01 false Suspension of rules. 99.4 Section 99.4 Public Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL ADMINISTRATION PROCEDURE FOR HEARINGS FOR THE CHILD CARE AND DEVELOPMENT FUND General § 99.4 Suspension of rules. With notice to all parties, the...

Absorption Spectra of Gold Nanoparticle Suspensions

Science.gov (United States)

Anan'eva, M. V.; Nurmukhametov, D. R.; Zverev, A. S.; Nelyubina, N. V.; Zvekov, A. A.; Russakov, D. M.; Kalenskii, A. V.; Eremenko, A. N.

2018-02-01

Three gold nanoparticle suspensions are obtained, and mean radii in distributions - (6.1 ± 0.2), (11.9 ± 0.3), and (17.3 ± 0.7) nm - are determined by the transmission electron microscopy method. The optical absorption spectra of suspensions are obtained and studied. Calculation of spectral dependences of the absorption index of suspensions at values of the gold complex refractive index taken from the literature showed a significant deviation of experimental and calculated data in the region of 450-800 nm. Spectral dependences of the absorption of suspensions are simulated within the framework of the Mie-Drude theory taking into account the interband absorption in the form of an additional term in the imaginary part of the dielectric permittivity of the Gaussian type. It is shown that to quantify the spectral dependences in the region of the plasmon absorption band of nanoparticles, correction of the parameters of the interband absorption is necessary in addition to the increase of the relaxation parameter of the Drude theory. Spectral dependences of the dielectric permittivity of gold in nanodimensional state are refined from the solution of the inverse problem. The results of the present work are important for predicting the special features of operation of photonic devices and optical detonators based on gold nanoparticles.

The assessment of cytokines in Quantiferon supernatants for the diagnosis of latent TB infection in a tribal population of Melghat, India.

Science.gov (United States)

Bapat, Prachi R; Husain, Aliabbas A; Daginawala, Hatim F; Agrawal, Neha P; Panchbhai, Milind S; Satav, Ashish R; Taori, Girdhar M; Kashyap, Rajpal S

2015-01-01

The tuberculin skin test (TST) and interferon-gamma release assays (IGRA), namely, the QuantiFERON-TB Gold test (QFT), remain the standard immunological diagnostic tools for latent tuberculosis (TB) infection (LTBI). However, the sub-optimal detection rates of both of these tests are major impediments in recognizing the population at risk. This study was aimed at evaluating additional cytokines besides interferon-gamma (IFN-γ) as biomarkers for improving LTBI diagnosis in the tribal population of Melghat, India. Seventy-four close TB contacts were stratified by QFT and TST results into: (i) QFT+/TST+ (n = 26), (ii) QFT+/TST- (n = 12), (iii) QFT-/TST- (n = 35) and (iv) QFT-/TST+ (n = 1) groups. A panel of cytokines (IL-6, IL-10, TNF-α and IL-2R) was then evaluated in antigen-stimulated QFT cell-free culture supernatants using IMMULITE-1000, an automated immunoassay analyzer. Cytokine estimation showed significantly higher levels of IL-6 in the QFT+/TST+ group, while significantly higher levels of IL-10 were found in the QFT-/TST- group. Correlation analysis identified a positive correlation between IL-6 and the QFT response (r = 0.6723, P < 0.0001), while a negative correlation was seen between QFT and IL-10 expression (r = -0.3271, P = 0.0044). Similarly, IL-6 was positively correlated with TST levels (r = 0.6631, P <0 .0001), and conversely, a negative correlation was found between TST and IL-10 expression (r = -0.5698, P < 0.0001). The positive and negative predictive values of IL-6 were found to be 92.59 and 93.33%, respectively, and the positive and negative predictive values of IL-10 were 96.55 and 91.18%, respectively. No significant impact of the demographic characteristics on cytokine positivity was observed. Our preliminary results suggest that the evaluation of additional cytokines in QFT cell-free culture supernatants may be valuable for the identification of LTBI. Combining IL-6 and IL-10 with QFT and/or TST could markedly improve the detection

Fuzzy logic control of vehicle suspensions with dry friction nonlinearity

Indian Academy of Sciences (India)

We design and investigate the performance of fuzzy logic-controlled (FLC) active suspensions on a nonlinear vehicle model with four degrees of freedom, without causing any degeneration in suspension working limits. Force actuators were mounted parallel to the suspensions. In this new approach, linear combinations of ...

31 CFR 19.605 - How does suspension differ from debarment?

Science.gov (United States)

2010-07-01

... 31 Money and Finance: Treasury 1 2010-07-01 2010-07-01 false How does suspension differ from debarment? 19.605 Section 19.605 Money and Finance: Treasury Office of the Secretary of the Treasury GOVERNMENTWIDE DEBARMENT AND SUSPENSION (NONPROCUREMENT) General Principles Relating to Suspension and Debarment...

12 CFR 513.4 - Suspension and debarment.

Science.gov (United States)

2010-01-01

... 12 Banks and Banking 5 2010-01-01 2010-01-01 false Suspension and debarment. 513.4 Section 513.4 Banks and Banking OFFICE OF THRIFT SUPERVISION, DEPARTMENT OF THE TREASURY PRACTICE BEFORE THE OFFICE § 513.4 Suspension and debarment. (a) The Office may censure any person practicing before it or may deny...

Effective viscosity of 2D suspensions - Confinement effects

Science.gov (United States)

Peyla, Philippe; Priem, Stephane; Vincent, Doyeux; Farutin, Alexander; Ismail, Mourad

2014-11-01

We study the rheology of a sheared 2D suspension of non-Brownian disks in presence of walls. Although, it is of course possible today with modern computers and powerful algorithms to perform direct numerical simulations that fully account for multiparticle 3D interactions, the analysis of the simple case of a 2D suspension, provides valuable insights and helps to understand 3D results. For instance, we examine the role of particle-wall and particle-particle interactions in determining the rheology of confined sheared suspensions. In addition we evaluate the intrinsic viscosity as well as the contribution of hydrodynamic interactions to the dissipation as a function of a wide range of confinements. Thanks to the direct visualisation of the whole 2D Stokes flow, we are able to give a clear interpretation about the rheology of semi-dilute confined suspensions.

Effect of carboxymethyl cellulose and ionic strength on stability of mineral suspensions in potash ore flotation systems.

Science.gov (United States)

Pawlik, M; Laskowski, J S; Ansari, A

2003-04-15

The adsorption of sodium carboxymethyl cellulose from aqueous solutions varying in ionic strength from that of distilled water to 50% NaCl/KCl brine (about 3.5 mol/dm(3)) onto illite and dolomite has been studied. The purpose of this work was to investigate the solvency effects in the phenomena underlying the potash flotation process that is carried out in saturated brine. Based on viscosity measurements, the adsorption results were analyzed in terms of a simple model of polymer macromolecules in solution. Suspension stability measurements carried out concomitantly with adsorption tests showed the ranges of carboxymethyl cellulose concentration over which the tested suspensions either were aggregated or were restabilized.

The measurement of the charging properties of fine particulate materials in pneumatic suspension

International Nuclear Information System (INIS)

Armour-Chelu, D.I.

1998-11-01

This document describes a programme of work that was designed to develop an improved understanding of the electrostatic charging properties of particulate materials with a view to applying this knowledge to the measurement of particulate concentrations in air-solid suspensions. An extensive literature review has been carried out. Some eighty published works were found and these concentrated on indirect charge measurement, the measurement of the two-phase pipe flow parameters, and on finding suitable models to explain tile work function given to insulators during metal to insulator contact. These areas are covered well in the field of electrostatics but data currently available in the area of programme of work being described here is very, limited, and so it is proposed that this research project will aim to improve such understanding. A test facility was developed to provide information from the flow of a particulate material under known conditions (particle velocity, suspension density). This test facility utilised three sensing probes, each with discrete charge amplifier units, at specific locations: one at the beginning and two further down the pipeline being utilised. Hence, the charging tendencies of any material were observed using this facility. The results obtained from this facility show the charging tendency of three particulate materials under various flow conditions. Signal processing techniques were developed to infer the suspension density for each flow condition and to estimate average particle velocity. Further analysis of the data resulted in tile derivation of a power spectral estimate for some of the flow conditions. This estimate was considered with the particle size distribution, as well as the estimate of tile average particle velocity, and there is a linkage. The main material selected for this programme was aluminium hydroxide. This was tested at environmental temperatures of 19 and 30 deg. C with relative humidity (RH) levels of 35, 45, and

Analysis of Driving Safety Criteria Based on National Regulations for the Suspension Systems of NGVs

Directory of Open Access Journals (Sweden)

Ronald Mauricio Martinod

2015-01-01

Full Text Available The work analyses the technical evaluation process of the suspension system for vehicles that have been adapted to natural-gas-fuelled engines from power light-duty gasoline, and diesel vehicles; this evaluation is done through a mechanical review established by national regulations. The development of this analysis is focused on establishing the relationship between the natural-gas-fuelled equipment and the dynamic effect caused by the extra-weight, according to two measuring criteria that determine the safety and driving comfort, these are: (i tire-road adhesion index; and (ii tire excitation phase angle. The paper also proposes new elements that can be added to the current national regulations and that are currently applied to assess the suspension of natural gas vehicles, recorded using a test standard benchmark for the evaluation of the suspension.

Simple additive manufacturing of an osteoconductive ceramic using suspension melt extrusion.

Science.gov (United States)

Slots, Casper; Jensen, Martin Bonde; Ditzel, Nicholas; Hedegaard, Martin A B; Borg, Søren Wiatr; Albrektsen, Ole; Thygesen, Torben; Kassem, Moustapha; Andersen, Morten Østergaard

2017-02-01

Craniofacial bone trauma is a leading reason for surgery at most hospitals. Large pieces of destroyed or resected bone are often replaced with non-resorbable and stock implants, and these are associated with a variety of problems. This paper explores the use of a novel fatty acid/calcium phosphate suspension melt for simple additive manufacturing of ceramic tricalcium phosphate implants. A wide variety of non-aqueous liquids were tested to determine the formulation of a storable 3D printable tricalcium phosphate suspension ink, and only fatty acid-based inks were found to work. A heated stearic acid-tricalcium phosphate suspension melt was then 3D printed, carbonized and sintered, yielding implants with controllable macroporosities. Their microstructure, compressive strength and chemical purity were analyzed with electron microscopy, mechanical testing and Raman spectroscopy, respectively. Mesenchymal stem cell culture was used to assess their osteoconductivity as defined by collagen deposition, alkaline phosphatase secretion and de-novo mineralization. After a rapid sintering process, the implants retained their pre-sintering shape with open pores. They possessed clinically relevant mechanical strength and were chemically pure. They supported adhesion of mesenchymal stem cells, and these were able to deposit collagen onto the implants, secrete alkaline phosphatase and further mineralize the ceramic. The tricalcium phosphate/fatty acid ink described here and its 3D printing may be sufficiently simple and effective to enable rapid, on-demand and in-hospital fabrication of individualized ceramic implants that allow clinicians to use them for treatment of bone trauma. Copyright © 2016 The Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

Load-cell based characterization system for a "Violin-Mode" shadow-sensor in advanced LIGO suspensions

Science.gov (United States)

Lockerbie, N. A.; Tokmakov, K. V.

2016-07-01

The background to this work was a prototype shadow sensor, which was designed for retro-fitting to an advanced LIGO (Laser Interferometer Gravitational wave Observatory) test-mass/mirror suspension, in which 40 kg test-mass/mirrors are each suspended by four approximately 600 mm long by 0.4 mm diameter fused-silica suspension fibres. The shadow sensor comprised a LED source of Near InfraRed (NIR) radiation and a rectangular silicon photodiode detector, which, together, were to bracket the fibre under test. The aim was to detect transverse Violin-Mode resonances in the suspension fibres. Part of the testing procedure involved tensioning a silica fibre sample and translating it transversely through the illuminating NIR beam, so as to measure the DC responsivity of the detection system to fibre displacement. However, an equally important part of the procedure, reported here, was to keep the fibre under test stationary within the beam, whilst trying to detect low-level AC Violin-Mode resonances excited on the fibre, in order to confirm the primary function of the sensor. Therefore, a tensioning system, incorporating a load-cell readout, was built into the test fibre's holder. The fibre then was excited by a signal generator, audio power amplifier, and distant loudspeaker, and clear resonances were detected. A theory for the expected fundamental resonant frequency as a function of fibre tension was developed and is reported here, and this theory was found to match closely with the detected resonant frequencies as they varied with tension. Consequently, the resonances seen were identified as being proper Violin-Mode fundamental resonances of the fibre, and the operation of the Violin-Mode detection system was validated.

Viscosity of aqueous and cyanate ester suspensions containing alumina nanoparticles

Energy Technology Data Exchange (ETDEWEB)

Lawler, Katherine [Iowa State Univ., Ames, IA (United States)

2009-01-01

The viscosities of both aqueous and cyanate ester monomer (BECy) based suspensions of alumina nanoparticle were studied. The applications for these suspensions are different: aqueous suspensions of alumina nanoparticles are used in the production of technical ceramics made by slip casting or tape casting, and the BECy based suspensions are being developed for use in an injection-type composite repair resin. In the case of aqueous suspensions, it is advantageous to achieve a high solids content with low viscosity in order to produce a high quality product. The addition of a dispersant is useful so that higher solids content suspensions can be used with lower viscosities. For BECy suspensions, the addition of nanoparticles to the BECy resin is expected to enhance the mechanical properties of the cured composite. The addition of saccharides to aqueous suspensions leads to viscosity reduction. Through DSC measurements it was found that the saccharide molecules formed a solution with water and this resulted in lowering the melting temperature of the free water according to classic freezing point depression. Saccharides also lowered the melting temperature of the bound water, but this followed a different rule. The shear thinning and melting behaviors of the suspensions were used to develop a model based on fractal-type agglomeration. It is believed that the structure of the particle flocs in these suspensions changes with the addition of saccharides which leads to the resultant viscosity decrease. The viscosity of the BECy suspensions increased with solids content, and the viscosity increase was greater than predicted by the classical Einstein equation for dilute suspensions. Instead, the Mooney equation fits the viscosity behavior well from 0-20 vol% solids. The viscosity reduction achieved at high particle loadings by the addition of benzoic acid was also investigated by NMR. It appears that the benzoic acid interacts with the surface of the alumina particle which may

21 CFR 520.1182 - Iron dextran suspension.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Iron dextran suspension. 520.1182 Section 520.1182... DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.1182 Iron dextran suspension... hydroxide in complex with a low molecular weight dextran. (b) Sponsor. See No. 051311 in § 510.600(c) of...

Research on magnetorheological damper suspension with permanent magnet and magnetic valve based on developed FOA-optimal control algorithm

Energy Technology Data Exchange (ETDEWEB)

Xiao, Ping; Gao, Hong [Anhui Polytechnic University, Wuhu (China); Niu, Limin [Anhui University of Technology, Maanshan (China)

2017-07-15

Due to the fail safe problem, it was difficult for the existing Magnetorheological damper (MD) to be widely applied in automotive suspensions. Therefore, permanent magnets and magnetic valves were introduced to existing MDs so that fail safe problem could be solved by the magnets and damping force could be adjusted easily by the magnetic valve. Thus, a new Magnetorheological damper with permanent magnet and magnetic valve (MDPMMV) was developed and MDPMMV suspension was studied. First of all, mechanical structure of existing magnetorheological damper applied in automobile suspensions was redesigned, comprising a permanent magnet and a magnetic valve. In addition, prediction model of damping force was built based on electromagnetics theory and Bingham model. Experimental research was onducted on the newly designed damper and goodness of fit between experiment results and simulated ones by models was high. On this basis, a quarter suspension model was built. Then, fruit Fly optimization algorithm (FOA)-optimal control algorithm suitable for automobile suspension was designed based on developing normal FOA. Finally, simulation experiments and bench tests with input surface of pulse road and B road were carried out and the results indicated that working erformance of MDPMMV suspension based on FOA-optimal control algorithm was good.

17 CFR 240.12d2-1 - Suspension of trading.

Science.gov (United States)

2010-04-01

... 17 Commodity and Securities Exchanges 3 2010-04-01 2010-04-01 false Suspension of trading. 240... Securities Exchange Act of 1934 Suspension of Trading, Withdrawal, and Striking from Listing and Registration § 240.12d2-1 Suspension of trading. (a) A national securities exchange may suspend from trading a...

Magnetic suspension and guidance of high speed vehicles. Final report

Energy Technology Data Exchange (ETDEWEB)

Alston, I A; Clark, J M; Hayden, J T

1972-12-01

Technical and economical assessments of magnetic suspensions for high speed vehicles and transport systems are reported. In these suspensions the suspending magnet takes the form of a powerful superconducting electromagnet that induces currents while it moves over conducting sheets or loops. A number of vehicle track designs are evaluated for operating cost effectiveness. It is shown that propulsion systems using power collected from the track are more expensive than those using power generated onboard the vehicle, and that the conducting sheet suspension is slightly more expensive than the null flux suspension.

Xenon-Water Interaction in Bacterial Suspensions as Studied by NMR

DEFF Research Database (Denmark)

Rodin, V.; Ponomarev, Alexander; Gerasimov, Maxim

2017-01-01

suspensions of Escherichia coli in the presence of xenon using nuclear magnetic resonance (NMR). The work studied how the spin-lattice relaxation times of water protons in suspension change under xenon conditions. Xenon is able to form clathrate hydrates with water molecules at a temperature above the melting...... point of ice. The work studied NMR relaxation times which reflect the rotation freedom of water molecules in suspension. Lower relaxation times indicate reduced rotational freedom of water. Single exponential behavior of spin-lattice relaxation of protons in the suspensions of microorganisms has been...

Stability of extemporaneously prepared rifaximin oral suspensions.

Science.gov (United States)

Cober, Mary Petrea; Johnson, Cary E; Lee, Jordan; Currie, Kenne

2010-02-15

The stability of extemporaneously prepared rifaximin oral suspensions was studied. An oral suspension of rifaximin 20 mg/mL was prepared by thoroughly grinding six 200-mg tablets of rifaximin in a glass mortar. Thirty milliliters of Ora-Plus and 30 mL of either Ora-Sweet or Ora-Sweet SF were mixed and added to the powder to make a final volume of 60 mL. Three identical samples of each formulation were prepared and placed in 2-oz amber plastic bottles with child-resistant caps and were stored at room temperature (23-25 degrees C). A 1-mL sample was withdrawn from each of the six bottles with a micropipette immediately after preparation and at 7, 15, 30, and 60 days. After further dilution to an expected concentration of 20 microg/mL with mobile phase, the samples were assayed in duplicate using stability-indicating high-performance liquid chromatography. The samples were visually examined for any color change and pH was tested on each day of analysis. Stability was determined by evaluating the percentage of the initial concentration remaining at each time point and defined as retention of at least 90% of the initial concentration of rifaximin. At least 99% of the initial rifaximin remained throughout the 60-day study period in both preparations. There were no detectable changes in color, odor, taste, or pH and no visible microbial growth in any sample. Extemporaneously prepared suspensions of rifaximin 20 mg/mL in 1:1 mixtures of Ora-Plus with either Ora-Sweet or Ora-Sweet SF were stable for at least 60 days when stored in 2-oz amber plastic bottles at room temperature.

Effective flocculation of fine mineral suspensions using Moringa oleifera seeds

Energy Technology Data Exchange (ETDEWEB)

Pickett, T.M. [Bureau of Mines, Reno, NV (United States)

1995-12-31

The purpose of this research was to investigate the feasibility of using Moringa oleifera seeds, or the active components of the seeds, in the clarification of waters containing suspended mineral fines. In comparative testing using a hematite suspension, the flocculating activity of Moringa oleifera seeds was better than alum. Twenty milligrams of seed powder was sufficient to clarify the hematite to near zero turbidity, while the same amount of alum had a minimal effect on turbidity. Extracts were prepared from the seeds in an attempt to separate the proteins. A crude protein extract was enriched by lowering the pH to 6.0. Only 0.08 mg/L of the enriched extract was required to flocculate a minusil suspension. Environmentally friendly protein flocculants could theoretically be produced and enhanced with recombinant DNA techniques as an alternative to chemical flocculants currently used in water treatment.

Design and analysis of an intelligent controller for active geometry suspension systems

Science.gov (United States)

Goodarzi, Avesta; Oloomi, Ehsan; Esmailzadeh, Ebrahim

2011-02-01

An active geometry suspension (AGS) system is a device to optimise suspension-related factors such as toe angle and roll centre height by controlling vehicle's suspension geometry. The suspension geometry could be changed through control of suspension mounting point's position. In this paper, analysis and control of an AGS system is addressed. First, the effects of suspension geometry change on roll centre height and toe angle are studied. Then, based on an analytical approach, the improvement of the vehicle's stability and handling due to the control of suspension geometry is investigated. In the next section, an eight-degree-of-freedom handling model of a sport utility vehicle equipped with an AGS system is introduced. Finally, a self-tuning proportional-integral controller has been designed, using the fuzzy control theory, to control the actuator that changes the geometry of the suspension system. The simulation results show that an AGS system can improve the handling and stability of the vehicle.

The role of sleep in predicting college academic performance: is it a unique predictor?

Science.gov (United States)

Taylor, Daniel J; Vatthauer, Karlyn E; Bramoweth, Adam D; Ruggero, Camilo; Roane, Brandy

2013-01-01

Few studies have looked at the predictability of academic performance (i.e., cumulative grade point average [GPA]) using sleep when common nonsleep predictors of academic performance are included. This project studied psychological, demographic, educational, and sleep risk factors of decreased academic performance in college undergraduates. Participants (N = 867) completed a questionnaire packet and sleep diary. It was hypothesized that low total sleep time (TST), increased sleep onset latency, later bedtimes, later wake times, and TST inconsistency would predict decreased academic performance. The most significant predictors of academic performance were high school GPA, standardized test scores (i.e., SAT/ACT), TST, time awake before arising (TWAK), TST inconsistency, and the quadratic terms of perceived stress (PSS) and TST.

Risk for tuberculosis among children

DEFF Research Database (Denmark)

Nakaoka, Hiroshi; Lawson, Lovett; Squire, S Bertel

2006-01-01

Contacts of adults with tuberculosis (TB) are at risk for infection. Tests based on interferon-gamma (IFN-gamma) expression in response to Mycobacterium tuberculosis antigens may be more sensitive than the tuberculin skin test (TST). Risk for infection was assessed by using TST and an IFN...

IMPROVEMENT OF BUS OPERATIONAL CHARACTERISTICS WHILE USING INTEGRATED CONTROL OF SUSPENSION AND TRANSMISSION

Directory of Open Access Journals (Sweden)

V. V. Mikhailau

2016-01-01

Full Text Available Semi-natural tests for active pneumatic suspension of a 18-tonne tourist bus with the system of automatic body stabilization of the mobile machine and feed-back coupling according to kinematics parameter. The test have been executed in the cases when the bus is stocked with an automatic hydro-mechanical transmission in the process of speed picking up, gear-changing or road braking which is assigned by accidental road humps. A computer simulation of dynamic structures in combination with virtual devices and real objects (HIL – Hardware-in-the-Loop Simulation has been carried in the paper. Personal computers, software, programmed logic controller, frequency generator, solenoid-operated valve have been used for the investigation process. The paper proposes an unconventional method for improvement operational characteristics which is based on integrated control of a suspension and automatic hydro-mechanical transmission. A mathematical model includes systems of automatic transmission, suspension and module for generation of accidental road humps. The model has been considered as a basis for semi-natural laboratory bench with industrially-manufactured controller, other components of automatic systems and standard control organs. The most efficient method for body stabilization is control of the suspension according to the parameter of angular rate during vertical turn of an automobile’s center line with a turning point in the center of mass. The developed algorithm and stabilization system according to angular rate of body’s center line turning have made it possible to improve dynamics of the bus while making gear-changing and to reduce fuel consumption during starting-up and speed picking-up processes. During the braking process such system simultaneously decreases oscillation amplitude of some parameters more than two-fold.

Transiently disordered tails accelerate folding of globular proteins.

Science.gov (United States)

Mallik, Saurav; Ray, Tanaya; Kundu, Sudip

2017-07-01

Numerous biological proteins exhibit intrinsic disorder at their termini, which are associated with multifarious functional roles. Here, we show the surprising result that an increased percentage of terminal short transiently disordered regions with enhanced flexibility (TstDREF) is associated with accelerated folding rates of globular proteins. Evolutionary conservation of predicted disorder at TstDREFs and drastic alteration of folding rates upon point-mutations suggest critical regulatory role(s) of TstDREFs in shaping the folding kinetics. TstDREFs are associated with long-range intramolecular interactions and the percentage of native secondary structural elements physically contacted by TstDREFs exhibit another surprising positive correlation with folding kinetics. These results allow us to infer probable molecular mechanisms behind the TstDREF-mediated regulation of folding kinetics that challenge protein biochemists to assess by direct experimental testing. © 2017 Federation of European Biochemical Societies.

Suspension Trauma / Orthostatic Intolerance

Science.gov (United States)

... Suspension Trauma/Orthostatic Intolerance Safety and Health Information Bulletin SHIB 03-24-2004, updated 2011 This Safety ... the harness, the environmental conditions, and the worker's psychological state all may increase the onset and severity ...

[Comparative study of concordance and costs between tuberculin skin test and QuantiFERON(®)-TB Gold In-Tube in the diagnosis of latent tuberculosis infection among contacts of patients with pulmonary tuberculosis].

Science.gov (United States)

Martinez Lacasa, Xavier; Canals Font, Roser; Jaen Manzanera, Angels; Cuchi Burgos, Eva; Lite Lite, Josep

2015-11-20

Recently diagnosis of latent tuberculosis infection (LTBI) can be made using the tuberculin skin test (TST) or by techniques known as interferon-γ release assays (IGRAS), being QuantiFERON(®)-TB Gold In-Tube (QF-G-IT) the most used. The IGRAS avoid some drawbacks of the TST, especially cross-reaction with bacillus Calmette-Guérin (BCG) vaccine, but also present some problems such as those arising from cost and the need of having an adequate infrastructure and experience. There is no clear consensus on which technique should be preferentially used for the diagnosis of LTBI. This is a comparative study between the TST and QT-G-IT in a cohort of contacts of patients with pulmonary tuberculosis during the study period. An analysis of global agreement and groups was performed according to whether the contacts were vaccinated with BCG or not. A study of costs of both techniques and diagnostic strategies based on these techniques was performed. The agreement between TST and QF-G-IT was acceptable in the whole sample yet it was very good in the unvaccinated group. Few cases of indeterminate values were recorded. The cost study showed that TST was cheaper than QF-G-IT; however when we analyzed the cost of the strategies according to each technique, the QF-G-IT showed a better cost-benefit. We suggest considering QF-G-IT as the only preferred technique for the diagnosis of LTBI in household contacts, based on good overall agreement between the 2 techniques (even if we eliminate the effect of the vaccine) and a cost analysis favorable to QF-G-IT. Copyright © 2015 Elsevier España, S.L.U. All rights reserved.

An efficient recursive least square-based condition monitoring approach for a rail vehicle suspension system

Science.gov (United States)

Liu, X. Y.; Alfi, S.; Bruni, S.

2016-06-01

A model-based condition monitoring strategy for the railway vehicle suspension is proposed in this paper. This approach is based on recursive least square (RLS) algorithm focusing on the deterministic 'input-output' model. RLS has Kalman filtering feature and is able to identify the unknown parameters from a noisy dynamic system by memorising the correlation properties of variables. The identification of suspension parameter is achieved by machine learning of the relationship between excitation and response in a vehicle dynamic system. A fault detection method for the vertical primary suspension is illustrated as an instance of this condition monitoring scheme. Simulation results from the rail vehicle dynamics software 'ADTreS' are utilised as 'virtual measurements' considering a trailer car of Italian ETR500 high-speed train. The field test data from an E464 locomotive are also employed to validate the feasibility of this strategy for the real application. Results of the parameter identification performed indicate that estimated suspension parameters are consistent or approximate with the reference values. These results provide the supporting evidence that this fault diagnosis technique is capable of paving the way for the future vehicle condition monitoring system.

Coupling Mechanism and Decoupled Suspension Control Model of a Half Car

Directory of Open Access Journals (Sweden)

Hailong Zhang

2016-01-01

Full Text Available A structure decoupling control strategy of half-car suspension is proposed to fully decouple the system into independent front and rear quarter-car suspensions in this paper. The coupling mechanism of half-car suspension is firstly revealed and formulated with coupled damping force (CDF in a linear function. Moreover, a novel dual dampers-based controllable quarter-car suspension structure is proposed to realize the independent control of pitch and vertical motions of the half car, in which a newly added controllable damper is suggested to be installed between the lower control arm and connection rod in conventional quarter-car suspension structure. The suggested damper constantly regulates the half-car pitch motion posture in a smooth and steady operation condition meantime achieving the expected completely structure decoupled control of the half-car suspension, by compensating the evolved CDF.

Shear-induced particle migration in suspensions of rods

Energy Technology Data Exchange (ETDEWEB)

Mondy, L.A. (Sandia National Laboratories, Albuquerque, New Mexico 87185 (United States)); Brenner, H. (Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)); Altobelli, S.A. (The Lovelace Institutes, 2425 Ridgecrest Drive, S. E., Albuquerque, New Mexico 87108 (United States)); Abbott, J.R.; Graham, A.L. (Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States))

1994-03-01

Shear-induced migration of particles occurs in suspensions of neutrally buoyant spheres in Newtonian fluids undergoing shear in the annular space between two rotating, coaxial cylinders (a wide-gap Couette), even when the suspension is in creeping flow. Previous studies have shown that the rate of migration of spherical particles from the high-shear-rate region near the inner (rotating) cylinder to the low-shear-rate region near the outer (stationary) cylinder increases rapidly with increasing sphere size. To determine the effect of particle shape, the migration of rods suspended in Newtonian fluids was recently measured. The behavior of several suspensions was studied. Each suspension contained well-characterized, uniform rods with aspect ratios ranging from 2 to 18 at either 0.30 or 0.40 volume fraction. At the same volume fraction of solids, the steady-state, radial concentration profiles for rods were independent of aspect ratio and were indistinguishable from those obtained from suspended spheres. Only minor differences near the walls (attributable to the finite size of the rods relative to the curvature of the walls) appeared to differentiate the profiles. Data taken during the transition from a well-mixed suspension to the final steady state show that the rate of migration increased as the volume of the individual rods increased.

Uniform Suspension of the Clustered Triamcinolone Acetonide Particle

Directory of Open Access Journals (Sweden)

Masahiko Sugimoto

2013-01-01

Full Text Available Purpose. MaQaid (MaQ is a new triamcinolone acetonide commercialised in Japan to visualize the vitreous. Because MaQ is preservative-free, it has a lower risk of ocular toxicities. However, since MaQ is only available as a powder, it needs suspenssion. Suspension does not always result uniformally, which causes poor visibility. This study reports a new MaQ suspension for better visibility. Methods. After medium addition to a MaQ vial, various methods were used. These included the use of (1 vortex mixer, (2 two syringes and a three-way stopcock, and (3 ultrasonic washer. We calculated suspended MaQ concentration (. To evaluate the reproducibility, we estimated the coefficient of variance (CV, . We used this MaQ for pig eyes, and vitreous visualization was simulated. Subsequently, we used this MaQ suspension for humans. Results. MaQ suspensions were sucessfull, and the concentrations of single particles increased significantly (. The CV was 36.1% for the routine method and 9.03% ffor the new method. Administration of a suspended MaQ made it possible to clearly visualize the vitreous in both pig and human eyes. Conclusions. We devised new techniques for uniformal MaQ suspension. These new methods can compensate for the MaQ disadvantages and ensure a safety surgery.

Potentials of Mangifera indica in the treatment of depressive-anxiety disorders: possible mechanisms of action.

Science.gov (United States)

Ishola, Ismail O; Awodele, Olufunsho; Eluogu, Chinedum O

2016-09-01

Mangifera indica (Anacardiaceae) is an important herb in the traditional African and Ayurvedic medicines. The stem barks are used in the treatment of hypertension, insomnia, tumour, depression, rheumatism and as a tonic. This study was carried out to investigate antidepressant- and anxiolytic-like effect of the hydroethanol stem bark extract of M. indica (HeMI) in mice. HeMI (12.5-100 mg/kg, p.o.) was administered 1 h before subjecting the animal to the forced swim test (FST), tail suspension test (TST) and elevated plus maze tests (EPM). HeMI (12.5-100 mg/kg, p.o.) treatment produced significant reduction in immobility time [F(6.56)=8.35, pindica through interaction with 5-HT2 receptor, α2-adrenoceptor and dopamine D2-receptors. Also, an anxiolytic-like effect through its affinity for 5-HT2 and benzodiazepine receptors. Hence, M. indica could be a potential phytotherapeutic agent in the treatment of mixed anxiety-depressive illness.

Lurasidone-β-cyclodextrin complexes: Physicochemical characterization and comparison of their antidepressant, antipsychotic activities against that of self microemulsifying formulation

Science.gov (United States)

Londhe, Vaishali Y.; Deshmane, Aishwarya B.; Singh, Sarita R.; Kulkarni, Yogesh A.

2018-04-01

Lurasidone hydrochloride (LHD) is an atypical antipsychotic drug has poor aqueous solubility and low bioavailability (9-19%). This study describes effect of different methods of complex formation with β-cyclodextrin (BCD) on enhancement of dissolution and on antidepressant, antipsychotic effects of LHD. Other purpose of this study is to compare pharmacodynamic effects of complexes with that of self microemulsifying drug delivery system of LHD (SMEDDS). Inclusion complexes (IC) of LHD and BCD were prepared by physical mixing (PM), kneading (KN) and spray drying (SD) in a 1:1 M ratio. These complexes were characterized by different techniques. KN and SD showing enhancement in dissolution, were compared with SMEDDS using Forced swim test (FST) and Tail suspension test (TST) for antidepressant action and Paw test for antipsychotic activity. Characterization of complexes confirmed interaction between LHD and BCD. Enhancement in dissolution is seen in following order SD > KN > PM > LHD. In all three animal models, SD, KN and SMEDDS showed statistically significant effect (p LHD.

Compressed Air Production Using Vehicle Suspension

OpenAIRE

Ninad Arun Malpure; Sanket Nandlal Bhansali

2015-01-01

Abstract Generally compressed air is produced using different types of air compressors which consumes lot of electric energy and is noisy. In this paper an innovative idea is put forth for production of compressed air using movement of vehicle suspension which normal is wasted. The conversion of the force energy into the compressed air is carried out by the mechanism which consists of the vehicle suspension system hydraulic cylinder Non-return valve air compressor and air receiver. We are co...

Professor Jesse W. Beams and the first practical magnetic suspension

Science.gov (United States)

Allaire, P. E.; Humphris, R. R.; Lewis, D. W.

1992-01-01

Dr. Jesse W. Beams developed the first practical magnetic suspension for high speed rotating devices. The devices included high speed rotating mirrors, ultracentrifuges, and high speed centrifugal field rotors. A brief biography of Dr. Beams is presented, and the following topics are discussed: (1) early axial magnetic suspension for ultracentrifuges; and (2) magnetic suspension for high centrifugal fields.

Comparison of fluoxetine and 1-methyl-L-tryptophan in treatment of depression-like illness in Bacillus Calmette-Guerin-induced inflammatory model of depression in mice.

Science.gov (United States)

Rana, Proteesh; Sharma, Amit K; Jain, Smita; Deshmukh, Pravin; Bhattacharya, S K; Banerjee, B D; Mediratta, Pramod K

2016-11-01

The inflammatory response system has been implicated in the pathophysiology of major depression. The pro-inflammatory cytokines like interferon-γ induce the enzyme indoleamine-2,3-dioxygenase (IDO) of the kynurenine pathway of tryptophan metabolism. The induction of IDO reduces the availability of tryptophan for serotonin synthesis. Furthermore, the metabolites of kynurenine pathway have neurotoxic property, which along with decreased serotonin may account for depression-like illness. The aim of this study was to compare the effects of treatment with fluoxetine and 1-methyl-L-tryptophan (1-MT) on Bacillus Calmette-Guerin (BCG)-induced inflammatory model of depression in mice. Behavioral tests included locomotor activity, forced swim test (FST) and tail suspension test (TST). Oxidative stress was assessed by examining the levels of thiobarbituric acid reactive species (TBARS) and non-protein thiols (NP-SH) in homogenized whole brain samples. Comet assays were performed to assess neurotoxicity. The results of this study demonstrate that BCG treatment resulted in an increase in duration of immobility in FST and TST as compared to the saline group. Further, it produced a significant increase in the brain TBARS levels and decrease in the brain NP-SH levels. The hippocampal tissue from BCG group had significantly more comet cells than the saline group. 1-MT and fluoxetine were able to reverse the BCG-induced depression-like behavior and the derangement in oxidative stress parameters. Fluoxetine and 1-MT also reversed the BCG-induced neurotoxicity in such mice. 1-Methyl-L-tryptophan exhibits antidepressant-like effect comparable to that of fluoxetine in treating BCG-induced depression-like behavior in mice.

Elevated Thyroid Peroxidase Antibody Increases Risk of Post-partum Depression by Decreasing Prefrontal Cortex BDNF and 5-HT Levels in Mice.

Science.gov (United States)

Zhou, Yingying; Wang, Xinyi; Zhao, Yuhang; Liu, Aihua; Zhao, Tong; Zhang, Yuanyuan; Shan, Zhongyan; Teng, Weiping

2016-01-01

Post-partum depression (PPD) is a common mental disease in the perinatal period that profoundly affects mothers and their offspring. Some clinical studies have found that PPD is related to thyroid peroxidase antibodies (TPOAbs); however, the mechanism underlying this relationship is unclear. Female C57BL/6 mice immunized with adenovirus encoding the cDNA of the full-length mTPO (mTPO-Ad) were used to establish the isolated TPOAb-positive mouse model in the present study. Maternal depressive-like behaviors were assessed using the forced swimming test (FST), sucrose preference test (SPT), and tail suspension test (TST) post-partum. The serum TPOAb titer was measured by enzyme-linked immunosorbent assay (ELISA) before pregnancy and post-partum. Furthermore, in the prefrontal cortex, the mRNA and protein expression levels of brain-derived neurotrophic factor (BDNF) were measured, serotonin (5-HT) levels were measured by ultra-high-performance liquid chromatography-tandem mass-spectrometry (UHPLC-MS/MS), and total thyroxine (TT4) levels were determined by ELISA. Compared with the controls, the mice immunized with mTPO-Ad displayed depressive behaviors, with a significantly lower sucrose preference (SP) at the 12-h time point and a longer immobility time in the FST and TST, which were accompanied by a lower expression of BDNF and 5-HT but no change in the TT4 concentration in the prefrontal cortex. Together, these findings suggest that elevated TPOAb may increase the risk of subsequent PPD and decrease the concentration of BDNF and 5-HT in the prefrontal cortex.

Graphite suspension in carbon dioxide; Suspension de graphite dans le gaz carbonique

Energy Technology Data Exchange (ETDEWEB)

Roche, R [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires; Moussez, C; Rouvillois, X; Brevet, R [Societe Nationale d' Etude et de Construction de Moteurs d' Aviation (SNECMA), 75 - Paris (France)

1965-07-01

Since 1963 the Atomic Division of SNECMA has been conducting, under a contract with the CEA, an experimental work with a two-component fluid comprised of carbon dioxide and small graphite particles. The primary purpose was the determination of basic engineering information pertaining to the stability and the flowability of the suspension. The final form of the experimental loop consists mainly of the following items: a light-phase compressor, a heavy-phase pump, an electrical-resistance type heater section, a cooling heat exchanger, a hairpin loop, a transparent test section and a separator. During the course of the testing, it was observed that the fluid could be circulated quite easily in a broad range of variation of the suspension density and velocity - density from 30 to 170 kg/m{sup 3} and velocity from 2 to 24 m/s. The system could be restarted and circulation maintained without any difficulty, even with the heavy-phase pump alone. The graphite did not have a tendency to pack or agglomerate during operation. No graphite deposition was observed on the wall of the tubing. A long period run (250 hours) has shown the evolution of the particle dimensions. Starting with graphite of surface area around 20 m{sup 2}/g (graphite particles about 1 {mu}), the powder surface area reaches an asymptotic value of 300 m{sup 2}/g (all the particles less than 0.3 {mu}). Moisture effect on flow stability, flow distribution between two parallel channels, pressure drop in straight tubes, recompression ratio in diffusers were also investigated. (author) [French] Depuis 1963 la Division Atomique de la SNECMA conduit, dans le cadre d'un contrat avec le Commissariat A l'Energie Atomique, l'etude experimentale d'une suspension de fines particules de graphite dans le gaz carbonique. L'objectif principal est d'obtenir des informations d'ordre mecanique et technologique sur la mise en oeuvre de l'ecoulement de ce fluide diphase. Le circuit experimental comprend principalement: un

Relative bioavailability, metabolism and tolerability of rectally administered oxcarbazepine suspension.

Science.gov (United States)

Clemens, Pamela L; Cloyd, James C; Kriel, Robert L; Remmel, Rory P

2007-01-01

Maintenance of effective drug concentrations is essential for adequate treatment of epilepsy. Some antiepileptic drugs can be successfully administered rectally when the oral route of administration is temporarily unavailable. Oxcarbazepine is a newer antiepileptic drug that is rapidly converted to a monohydroxy derivative, the active compound. This study aimed to characterise the bioavailability, metabolism and tolerability of rectally administered oxcarbazepine suspension using a randomised, crossover design in ten healthy volunteers. Two subjects received 300 mg doses of oxcarbazepine suspension via rectal and oral routes and eight received 450 mg doses. A washout period of at least 2 weeks elapsed between doses. The rectal dose was diluted 1:1 with water. Blood samples and urine were collected for 72 hours post-dose. Adverse effects were assessed at each blood collection time-point using a self-administered questionnaire. Plasma was assayed for oxcarbazepine and monohydroxy derivative; urine was assayed for monohydroxy derivative and monohydroxy derivative-glucuronide. Maximum plasma concentration (C(max)) and time to reach C(max) (t(max)) were obtained directly from the plasma concentration-time curves. The areas under the concentration-time curve (AUCs) were determined via non-compartmental analysis. Relative bioavailability was calculated and the C(max) and AUCs were compared using Wilcoxon signed-rank tests. Mean relative bioavailability calculated from plasma AUCs was 8.3% (SD 5.5%) for the monohydroxy derivative and 10.8% (SD 7.3%) for oxcarbazepine. Oxcarbazepine and monohydroxy derivative C(max) and AUC values were significantly lower following rectal administration (p effects were headache and fatigue with no discernible differences between routes. Monohydroxy derivative bioavailability following rectal administration of oxcarbazepine suspension is significantly lower than following oral administration, most likely because of poor oxcarbazepine water

Assessment of railway wagon suspension characteristics

Science.gov (United States)

Soukup, Josef; Skočilas, Jan; Skočilasová, Blanka

2017-05-01

The article deals with assessment of railway wagon suspension characteristics. The essential characteristics of a suspension are represented by the stiffness constants of the equivalent springs and the eigen frequencies of the oscillating movements in reference to the main central inertia axes of a vehicle. The premise of the experimental determination of these characteristic is the knowledge of the gravity center position and the knowledge of the main central inertia moments of the vehicle frame. The vehicle frame performs the general spatial movement when the vehicle moves. An analysis of the frame movement generally arises from Euler's equations which are commonly used for the description of the spherical movement. This solution is difficult and it can be simplified by applying the specific assumptions. The eigen frequencies solutions and solutions of the suspension stiffness are presented in the article. The solutions are applied on the railway and road vehicles with the simplifying conditions. A new method which assessed the characteristics is described in the article.

15 CFR 2011.110 - Suspension of certificate system.

Science.gov (United States)

2010-01-01

..., SYRUPS AND MOLASSES Certificate of Quota Eligibility § 2011.110 Suspension of certificate system. (a... of such suspension and the effective date thereof shall be published in the Federal Register. (b... such reinstatement and the effective date thereof shall be published in the Federal Register. (c...

Aeroelastic Stability of Suspension Bridges using CFD

DEFF Research Database (Denmark)

Stærdahl, Jesper Winther; Sørensen, Niels; Nielsen, Søren R.K.

2007-01-01

using CFD models and the aeroelastic stability boundary has been successfully determined when comparing two-dimensional flow situations using wind tunnel test data and CFD methods for the flow solution and two-degrees-of-freedom structural models in translation perpendicular to the flow direction......In recent years large span suspension bridges with very thin and slender profiles have been built without proportional increasing torsional and bending stiffness. As a consequence large deformations at the mid-span can occur with risk of aeroelastic instability and structural failure. Analysis...... of aeroelastic stability also named flutter stability is mostly based on semi-empirical engineering models, where model specific parameters, the so-called flutter derivatives, need calibration from wind tunnel tests or numerical methods. Several papers have been written about calibration of flutter derivatives...

Influence of crystal habit on trimethoprim suspension formulation.

Science.gov (United States)

Tiwary, A K; Panpalia, G M

1999-02-01

The role of crystal habit in influencing the physical stability and pharmacokinetics of trimethoprim suspensions was examined. Different habits for trimethoprim (TMP) were obtained by recrystallizing the commercial sample (PD) utilizing solvent-change precipitation method. Four distinct habits (microscopic observation) belonging to the same polymorphic state (DSC studies) were selected for studies. Preformulation and formulation studies were carried out on suspension dosage forms containing these crystals. The freshly prepared suspensions were also evaluated for their pharmacokinetic behaviour on healthy human volunteers using a cross over study. Variation of crystallization conditions produces different habits of TMP. Among the different crystal habits exhibiting same polymorphic state, the most anisometric crystal showed best physical stability in terms of sedimentation volume and redispersibility. However, habit did not significantly affect the extent of TMP excreted in urine. Modification of surface morphology without significantly altering the polymorphic state can be utilized for improving physical stability of TMP suspensions. However, the pharmacokinetic profile remains unaltered.

Study of shear thickening behavior in colloidal suspensions

Directory of Open Access Journals (Sweden)

N Maleki Jirsaraee

2015-01-01

Full Text Available We studied the shear thickening behavior of the nano silica suspension (silica nanoparticles 12 nm in size suspended in ethylene glycol under steady shear. The critical shear rate for transition into shear thickening phase was determined at different concentrations and temperatures. The effect of temperature and concentration was studied on the shear thickening behavior. In silica suspension, it was observed that all the samples had a transition into shear thickening phase and also by increasing the temperature, critical shear rate increased and viscosity decreased. Our observations showed that movement in silica suspension was Brownian and temperature could cause a delay in transition into shear thickening phase. Yet, we observed that increasing the concentration would decrease critical shear rate and increase viscosity. Increasing temperature increased Brownian forces and increasing concentration increased hydrodynamic forces, confirming the contrast between these two forces for transition into shear thickening phase for the suspensions containing nano particles

Suspension feeding in adult Nephrops norvegicus (L.) and Homarus gammarus (L.) (decapoda)

Science.gov (United States)

Loo, Lars-Ove; Pihl Baden, Susanne; Ulmestrand, Mats

Suspension feeding in adults of the Norway lobster Nephrops norvegicus (40-74 g) and the European lobster Homarus gammarus (280-350 g) was tested in experiments offering planktonic food items of different sizes from 200 to 600 μm and measuring the clearing capacity. Both lobster species were found to effectively clear water of food particles comprising nauplii of the brine shrimp Artemia salina of about 600 μm in size. These were reduced to 50% of the initial concentration within 5 h and to 90% within 12 h. When N. norvegicus was offered food particles averaging 200 μm, a significant reduction in average size occurred, indicating that the minimum retention size is around 200 μm. Fluorescently dyed Artemia salina were recovered in the stomach and intestine of lobsters proving that the filtered particles are passed to the digestive tract. Results from other experiments, using the blood pigment (haemocyanin) concentration as an index of nutritional state, indicated that the lobsters can get some nutritional advantage from suspension feeding. Suspension feeding in larger decapods has not been described previously, so the significance of this finding is discussed with respect to changes in behavioural and ecological role.

Equivalent Air Spring Suspension Model for Quarter-Passive Model of Passenger Vehicles.

Science.gov (United States)

Abid, Haider J; Chen, Jie; Nassar, Ameen A

2015-01-01

This paper investigates the GENSIS air spring suspension system equivalence to a passive suspension system. The SIMULINK simulation together with the OptiY optimization is used to obtain the air spring suspension model equivalent to passive suspension system, where the car body response difference from both systems with the same road profile inputs is used as the objective function for optimization (OptiY program). The parameters of air spring system such as initial pressure, volume of bag, length of surge pipe, diameter of surge pipe, and volume of reservoir are obtained from optimization. The simulation results show that the air spring suspension equivalent system can produce responses very close to the passive suspension system.

Particle Image Velocimetry (PIV) Measurements of Suspension-Feeding Velocities

Science.gov (United States)

Du Clos, K.; Jones, I. T.; Carrier, T. J.; Jumars, P. A.

2016-02-01

Active suspension feeders, such as bivalves and tunicates, connect benthic and pelagic ecosystems by packaging suspended matter into larger fecal and pseudofecal particles, greatly enhancing the flux of carbon and nutrients from the water column to the benthos. The volume of water processed by a population of suspension feeders is commonly estimated by scaling up results from experiments that measure the clearance rate (the volume of water cleared of particles per time) of one or a few individual suspension feeders. Clearance rates vary, however, between species, within a species, and over time for a single individual; and the velocity fields produced by suspension feeders are likely to interact in complex ways. We measured the water velocity fields produced by two species of bivalve, Mya arenaria and Mercenaria mercenaria, and the tunicate Ciona intestinalis, using particle image velocimetry (PIV). We used these measurements to calculate flow rates and Reynolds numbers of inhalant and exhalant siphons. We also observed strong entrainment of water by M. arenaria's exhalant siphon jet that may help to explain how the clam avoids depleting the water around it of particles and oxygen as it feeds. We are using these measurements to inform computational fluid mechanics (CFD) models of suspension feeding, allowing us to examine the interactions of flow fields produced by multiple suspension feeders and other effects not quantified by clearance-rate measurements.

Development of the Nissan hydraulic active suspension. Nissan yuatsu active suspension no kaihatsu

Energy Technology Data Exchange (ETDEWEB)

Kawarasaki, y.; Fukunaga, Y.; Hasegawa, S.; Okuyama, Y.; Omura, I.; Takahashi, K.; Abe, S.; Tsuruta, E. (Nissan Motor Co. Ltd., Tokyo (Japan))

1989-12-25

A hydraulic active suspension system, Nissan original product, was developed and mass produced for the first time in the world. The system incorporates a sufficient power source, a high accuracy sensor and a high response device for continuous and intended vehicle control and at the same time delivers high levels of ride comfort and driving performance. The suspension system has four innovative features: skyhook damping, active roll and pitching control, a frequency-dependent damping mechanism, and active steering characteristics control. Under all road and operating conditions, the system actively suppresses vehicle attitude changes and unnecessary movement, and also gently absorbs inputs from the road. This epoch-making system provides a dramatic improvement in vehicle performance, and has been adopted in the Infiniti Q45 luxury sedan. 2 refs., 20 figs., 4 tabs.

14 CFR 1274.927 - Debarment and suspension and Drug-Free Workplace.

Science.gov (United States)

2010-01-01

... Workplace. 1274.927 Section 1274.927 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION... suspension and Drug-Free Workplace. Debarment and Suspension and Drug-Free Workplace April 2007 NASA... Suspension (Nonprocurement) and 14 CFR part 1267, Government-wide requirements for Drug-Free Workplace...

Effect of solvent composition on dispersing ability of reaction sialon suspensions.

Science.gov (United States)

Xu, Xin; Oliveira, Marta; Ferreira, José M F

2003-03-15

This work focuses on the optimization of the rheological behavior of suspensions considering different solvent compositions. The effects of methyl ethyl ketone (MEK)/ethanol (E) solvent mixtures on reaction sialon suspensions were investigated by measuring sedimentation behavior, adsorption of dispersant, and flow behavior. It was shown that both the flow behavior and the sedimentation behavior strongly depended on selection of solvent composition. Using 3 wt% KD1 as dispersant, well-dispersed colloidal suspensions could be obtained in MEK-rich solvents. The suspensions with 60 vol% MEK/40 vol% E as solvent could be fitted to the Bingham model with very low yield stress, while suspensions with pure MEK or ethanol-rich mixtures as solvent showed pseudo plastic behavior with relatively high yield stress values. A model was proposed to explain the different flow behaviors of suspensions considering the different configurations of dispersant at particles' surfaces.

2 CFR 180.740 - Are suspension proceedings formal?

Science.gov (United States)

2010-01-01

... 2 Grants and Agreements 1 2010-01-01 2010-01-01 false Are suspension proceedings formal? 180.740 Section 180.740 Grants and Agreements OFFICE OF MANAGEMENT AND BUDGET GOVERNMENTWIDE GUIDANCE FOR GRANTS... suspension decision. (b) You as a respondent or your representative must submit any documentary evidence you...

12 CFR 19.243 - Removal, suspension, or debarment.

Science.gov (United States)

2010-01-01

... 12 Banks and Banking 1 2010-01-01 2010-01-01 false Removal, suspension, or debarment. 19.243 Section 19.243 Banks and Banking COMPTROLLER OF THE CURRENCY, DEPARTMENT OF THE TREASURY RULES OF PRACTICE AND PROCEDURE Removal, Suspension, and Debarment of Accountants From Performing Audit Services § 19...

Radiation resistivity of frozen insulin solutions and suspensions

Energy Technology Data Exchange (ETDEWEB)

Soboleva, N N; Ivanova, A I; Talrose, V L; Trofimov, V I; Fedotov, V P [AN SSSR, Moscow. Inst. Fizicheskoj Khimii; Research Institute for Biological Testing of Chemicals, Moscow (USSR); Institute of Experimental Endocrinology and Hormon Chemistry, Moscow (USSR))

1981-10-01

The effect of great increase in radiation resistance of insulin solutions and suspensions after irradiation at low temperatures in the frozen state was observed by absorption spectrophotometry, paper chromatography and biological analysis. The data obtained suggest irradiation of frozen insulin solutions and suspensions as a method for its sterilization.

Intelligent systems of the vehicles’ suspension

Science.gov (United States)

Yurlin, D.

2018-02-01

The article is devoted to the current condition of car’s active suspension system. It presents the tendencies in development of the active systems of suspension system, adjustable elements incorporated in them and the companies succeeded in designing such systems. It also mirrors the problem of impact of active systems on car’s safety and their importance for the driver. Advantages and disadvantages of the most common types of active elements are being described, analyzed and compared. The author concludes about the perspectives of these systems’ development.

X-ray measurements during plasma current start-up experiments using the lower hybrid wave on the TST-2 spherical tokamak

International Nuclear Information System (INIS)

Wakatsuki, Takuma; Ejiri, Akira; Kakuda, Hidetoshi

2012-01-01

Non-inductive plasma current start-up experiments using RF power in the lower hybrid frequency range is being conducted on the TST-2 spherical tokamak. Plasma currents of up to 15 kA have been achieved. The effect of direct current drive can be seen by comparing the cases with co-drive and counter-drive. X-rays in various energy ranges were measured to investigate the interaction between the wave and the electrons. Soft X-ray (SX) measurements revealed that the perpendicular SX emission increased significantly as the plasma current increased, and that the tangential SX emission in the direction of RF drive was enhanced more strongly in the co-drive case compared to the counter-drive case. These observations imply that the fast electrons accelerated by the lower hybrid wave contribute to the plasma current. However, RF amplitude modulation experiments showed that the confinement time of these fast electrons are very short (less than 0.05 ms), much shorter than the collisional slowing down time. Hard X-ray spectral measurements showed that the radiation temperature of fast electrons in the co-direction for current drive was higher than that in the counter-direction. These observations are consistent with the existence of RF-driven fast electrons. (author)

Ceramic Near-Net Shaped Processing Using Highly-Loaded Aqueous Suspensions

Science.gov (United States)

Rueschhoff, Lisa

rheological modification and improved green body strength. Test bars formed via this process were sintered to high densities (up to 97% TD) without the use of external pressure, and had complete conversion to the desirable beta-Si3N4 phase with high flexural strengths up to 700 MPa. The specimen sets with the smallest average pore size on the fracture surface (77 mum) had the highest average flexural strengths of 573 MPa. The hardness of all specimens was approximately 16 GPa. The water-based suspensions, ease and low cost of processing, and robust mechanical properties obtained demonstrate this as a viable process for the economical and environmentally friendly production of Si3N4 parts. Finally, additive manufacturing was also used as a method to overcome ceramic forming difficulties and to create near-net shaped dense components via room-temperature direct ink writing. In this processes, highly loaded aqueous alumina suspensions were extruded in a layer-by-layer fashion using a low-cost syringe style 3D printer. With alumina as a model material, the effect of solids loading on rheology, specimen uniformity, density, microstructure, and mechanical properties was studied. All suspensions contained a polymer binder ( 5 vol.%), dispersant, and 51 to 58 vol.% alumina powder. Rheological measurements indicated all suspensions to be yield-pseudoplastic, and both yield stress and viscosity were found to increase with increasing alumina solids loading. Shear rates ranging from 19.5 to 24.2 s-1, corresponding to viscosities of 9.8 to 17.2 Pa·s, for the 53 - 56 vol.% alumina suspensions were found to produce the best results for the 1.25 mm tip employed during writing. All parts were sintered to greater than 98% of true density, with grain sizes ranging from 3.2 to 3.7 mum. The average flexure strength, which ranged from 134 to 157 MPa, was not influenced by the alumina solids loading. In limited study, additive manufacturing of silicon nitride suspensions stabilized with a WRA has

Rheology of organoclay suspension

CSIR Research Space (South Africa)

Hato, MJ

2011-05-01

Full Text Available The authors have studied the rheological properties of clay suspensions in silicone oil, where clay surfaces were modified with three different types of surfactants. Dynamic oscillation measurements showed a plateau-like behavior for all...

Origins of microstructural transformations in charged vesicle suspensions: the crowding hypothesis.

Science.gov (United States)

Seth, Mansi; Ramachandran, Arun; Murch, Bruce P; Leal, L Gary

2014-09-02

It is observed that charged unilamellar vesicles in a suspension can spontaneously deflate and subsequently transition to form bilamellar vesicles, even in the absence of externally applied triggers such as salt or temperature gradients. We provide strong evidence that the driving force for this deflation-induced transition is the repulsive electrostatic pressure between charged vesicles in concentrated suspensions, above a critical effective volume fraction. We use volume fraction measurements and cryogenic transmission electron microscopy imaging to quantitatively follow both the macroscopic and microstructural time-evolution of cationic diC18:1 DEEDMAC vesicle suspensions at different surfactant and salt concentrations. A simple model is developed to estimate the extent of deflation of unilamellar vesicles caused by electrostatic interactions with neighboring vesicles. It is determined that when the effective volume fraction of the suspension exceeds a critical value, charged vesicles in a suspension can experience "crowding" due to overlap of their electrical double layers, which can result in deflation and subsequent microstructural transformations to reduce the effective volume fraction of the suspension. Ordinarily in polydisperse colloidal suspensions, particles interacting via a repulsive potential transform into a glassy state above a critical volume fraction. The behavior of charged vesicle suspensions reported in this paper thus represents a new mechanism for the relaxation of repulsive interactions in crowded situations.

Rheological studies of aqueous stabilised nano-zirconia particle suspensions

Directory of Open Access Journals (Sweden)

Asad Ullah Khan

2012-02-01

Full Text Available In the present investigation aqueous suspensions of nano- and colloidal range particles are stabilised by changing the ambient pH. Rheology is used to establish the stability of the suspensions and it is found that the rheology of the suspensions is strongly dependent on the pH values. The viscosity is highest close to the iso-electric point of the powders. At the iso-electric point the net surface charge on the powder particles is zero and is the cause of the high viscosity. Away from the iso-electric point, the particles are charged, giving rise to a double layer phenomenon and causing the reduction in viscosity. It is also found that increasing the solid contents of the suspensions reduces the pH region of low viscosity.

Electrochemical study of AISI 304 stainless steel during the exposure at the disinfectant solutions with fungal suspensions

Energy Technology Data Exchange (ETDEWEB)

Stoica, M.; Bruma, M. [Department of Biochemistry and Technologies, Faculty of Food Science and Engineering, ' ' Dunarea de Jos' ' University of Galati, 111 Domneasca Street, 800201 Galati (Romania); Carac, G. [Department of Chemistry, Faculty of Sciences, ' ' Dunarea de Jos' ' University of Galati, 47 Domneasca Street, 800008 Galati (Romania)

2010-12-15

The effect of fungal suspensions on the disinfectant solution (Actisept with sodium dichloroisocyanurate as active substance, which releases 140 ppm active chlorine) and the corrosion behavior of type AISI 304 stainless steel (SS) were evaluated through linear polarization. The work presents a study of biocide Actisept solution as reference solution and the mixed solutions: reference biocide Actisept solution with three fungal suspensions (10 vol%), Aspergillus niger, Candida mycoderma, and Saccharomyces cerevisiae. The fungal suspension has an important influence on the synergistic effect of the SS corrosion in the following order: Saccharomyces cerevisiae > Candida mycoderma > Aspergillus niger. The E{sub corr} values from the mixed solutions decreased with immersion time of the samples. In the case of Aspergillus niger, the corrosion rate was lower than that of any other type of fungal suspension tested, because the arrangement in solutions, the size and composition of Aspergillus niger spores were more favorable to protect the spores of the chemical and the electrical stressing. The results showed that there is a synergistic effect between the active substances from the disinfectant, fungal suspensions and applied potential, thus this effect can be taken into consideration for the hygienic and safety food industry. (Copyright copyright 2010 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Load-cell based characterization system for a “Violin-Mode” shadow-sensor in advanced LIGO suspensions

Energy Technology Data Exchange (ETDEWEB)

Lockerbie, N. A.; Tokmakov, K. V. [SUPA (Scottish Universities Physics Alliance) Department of Physics, University of Strathclyde, 107 Rottenrow, Glasgow G4 0NG (United Kingdom)

2016-07-15

The background to this work was a prototype shadow sensor, which was designed for retro-fitting to an advanced LIGO (Laser Interferometer Gravitational wave Observatory) test-mass/mirror suspension, in which 40 kg test-mass/mirrors are each suspended by four approximately 600 mm long by 0.4 mm diameter fused-silica suspension fibres. The shadow sensor comprised a LED source of Near InfraRed (NIR) radiation and a rectangular silicon photodiode detector, which, together, were to bracket the fibre under test. The aim was to detect transverse Violin-Mode resonances in the suspension fibres. Part of the testing procedure involved tensioning a silica fibre sample and translating it transversely through the illuminating NIR beam, so as to measure the DC responsivity of the detection system to fibre displacement. However, an equally important part of the procedure, reported here, was to keep the fibre under test stationary within the beam, whilst trying to detect low-level AC Violin-Mode resonances excited on the fibre, in order to confirm the primary function of the sensor. Therefore, a tensioning system, incorporating a load-cell readout, was built into the test fibre’s holder. The fibre then was excited by a signal generator, audio power amplifier, and distant loudspeaker, and clear resonances were detected. A theory for the expected fundamental resonant frequency as a function of fibre tension was developed and is reported here, and this theory was found to match closely with the detected resonant frequencies as they varied with tension. Consequently, the resonances seen were identified as being proper Violin-Mode fundamental resonances of the fibre, and the operation of the Violin-Mode detection system was validated.

Load-cell based characterization system for a “Violin-Mode” shadow-sensor in advanced LIGO suspensions

International Nuclear Information System (INIS)

Lockerbie, N. A.; Tokmakov, K. V.

2016-01-01

The background to this work was a prototype shadow sensor, which was designed for retro-fitting to an advanced LIGO (Laser Interferometer Gravitational wave Observatory) test-mass/mirror suspension, in which 40 kg test-mass/mirrors are each suspended by four approximately 600 mm long by 0.4 mm diameter fused-silica suspension fibres. The shadow sensor comprised a LED source of Near InfraRed (NIR) radiation and a rectangular silicon photodiode detector, which, together, were to bracket the fibre under test. The aim was to detect transverse Violin-Mode resonances in the suspension fibres. Part of the testing procedure involved tensioning a silica fibre sample and translating it transversely through the illuminating NIR beam, so as to measure the DC responsivity of the detection system to fibre displacement. However, an equally important part of the procedure, reported here, was to keep the fibre under test stationary within the beam, whilst trying to detect low-level AC Violin-Mode resonances excited on the fibre, in order to confirm the primary function of the sensor. Therefore, a tensioning system, incorporating a load-cell readout, was built into the test fibre’s holder. The fibre then was excited by a signal generator, audio power amplifier, and distant loudspeaker, and clear resonances were detected. A theory for the expected fundamental resonant frequency as a function of fibre tension was developed and is reported here, and this theory was found to match closely with the detected resonant frequencies as they varied with tension. Consequently, the resonances seen were identified as being proper Violin-Mode fundamental resonances of the fibre, and the operation of the Violin-Mode detection system was validated.

Adaptive tracking control for active suspension systems with non-ideal actuators

Science.gov (United States)

Pan, Huihui; Sun, Weichao; Jing, Xingjian; Gao, Huijun; Yao, Jianyong

2017-07-01

As a critical component of transportation vehicles, active suspension systems are instrumental in the improvement of ride comfort and maneuverability. However, practical active suspensions commonly suffer from parameter uncertainties (e.g., the variations of payload mass and suspension component parameters), external disturbances and especially the unknown non-ideal actuators (i.e., dead-zone and hysteresis nonlinearities), which always significantly deteriorate the control performance in practice. To overcome these issues, this paper synthesizes an adaptive tracking control strategy for vehicle suspension systems to achieve suspension performance improvements. The proposed control algorithm is formulated by developing a unified framework of non-ideal actuators rather than a separate way, which is a simple yet effective approach to remove the unexpected nonlinear effects. From the perspective of practical implementation, the advantages of the presented controller for active suspensions include that the assumptions on the measurable actuator outputs, the prior knowledge of nonlinear actuator parameters and the uncertain parameters within a known compact set are not required. Furthermore, the stability of the closed-loop suspension system is theoretically guaranteed by rigorous mathematical analysis. Finally, the effectiveness of the presented adaptive control scheme is confirmed using comparative numerical simulation validations.

The Evolution of Discipline: Alternative to Suspension Programs.

Science.gov (United States)

Streva, Michael A.

Historically, the chosen method of discipline in United States schools has gone from corporal punishment to an emphasis on suspension. Recently, as principals have become less certain about the extent of their authority to suspend students, many inschool programs have been developed as alternatives to suspension. Among the advantages of such…

21 CFR 1314.155 - Suspension pending final order.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 9 2010-04-01 2010-04-01 false Suspension pending final order. 1314.155 Section 1314.155 Food and Drugs DRUG ENFORCEMENT ADMINISTRATION, DEPARTMENT OF JUSTICE RETAIL SALE OF SCHEDULED LISTED CHEMICAL PRODUCTS Order to Show Cause § 1314.155 Suspension pending final order. (a) The...

38 CFR 21.3043 - Suspension of program; child.

Science.gov (United States)

2010-07-01

... 38 Pensions, Bonuses, and Veterans' Relief 2 2010-07-01 2010-07-01 false Suspension of program; child. 21.3043 Section 21.3043 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS... 38 U.S.C. Chapter 35 Eligibility and Entitlement § 21.3043 Suspension of program; child. For an...

Formulation of cefuroxime axetil oral suspension and investigation of its pharmaceutical properties

OpenAIRE

Valizadeh, Hadi; Farajnia, Aynoor; Zakeri-Milani, Parvin

2011-01-01

Purpose: Cefuroxime is the second generation cephalosporin, which its intravenous and oral dosage forms are available. Oral route is the selective method for administration of most of the drugs. The aim of this study was formulating ‘for oral’ cefuroxime axetil suspensions. Methods: Minitab (ver.15) was used to design the formulations containing 125 mg of cefuroxime in 5 ml vehicle. After selecting the acceptable preparations, physical stability tests and other tests such as dissolution rate,...

41 CFR 109-40.103-2 - Disqualification and suspension of carriers.

Science.gov (United States)

2010-07-01

... suspension of carriers. 109-40.103-2 Section 109-40.103-2 Public Contracts and Property Management Federal... AVIATION, TRANSPORTATION, AND MOTOR VEHICLES 40-TRANSPORTATION AND TRAFFIC MANAGEMENT 40.1-General Provision § 109-40.103-2 Disqualification and suspension of carriers. Disqualification and suspension are...

Bulk and interfacial stresses in suspensions of soft and hard colloids

International Nuclear Information System (INIS)

Truzzolillo, D; Roger, V; Dupas, C; Cipelletti, L; Mora, S

2015-01-01

We explore the influence of particle softness and internal structure on both the bulk and interfacial rheological properties of colloidal suspensions. We probe bulk stresses by conventional rheology, by measuring the flow curves, shear stress versus strain rate, for suspensions of soft, deformable microgel particles and suspensions of near hard-sphere-like silica particles. A similar behaviour is seen for both kinds of particles in suspensions at concentrations up to the random close packing volume fraction, in agreement with recent theoretical predictions for sub-micron colloids. Transient interfacial stresses are measured by analyzing the patterns formed by the interface between the suspensions and their solvent, due to a generalized Saffman–Taylor hydrodynamic instability. At odds with the bulk behaviour, we find that microgels and hard particle suspensions exhibit vastly different interfacial stress properties. We propose that this surprising behaviour results mainly from the difference in particle internal structure (polymeric network for microgels versus compact solid for the silica particles), rather than softness alone. (paper)

Size-selective separation of submicron particles in suspensions with ultrasonic atomization.

Science.gov (United States)

Nii, Susumu; Oka, Naoyoshi

2014-11-01

Aqueous suspensions containing silica or polystyrene latex were ultrasonically atomized for separating particles of a specific size. With the help of a fog involving fine liquid droplets with a narrow size distribution, submicron particles in a limited size-range were successfully separated from suspensions. Performance of the separation was characterized by analyzing the size and the concentration of collected particles with a high resolution method. Irradiation of 2.4MHz ultrasound to sample suspensions allowed the separation of particles of specific size from 90 to 320nm without regarding the type of material. Addition of a small amount of nonionic surfactant, PONPE20 to SiO2 suspensions enhanced the collection of finer particles, and achieved a remarkable increase in the number of collected particles. Degassing of the sample suspension resulted in eliminating the separation performance. Dissolved air in suspensions plays an important role in this separation. Copyright © 2014 Elsevier B.V. All rights reserved.

DC electrostatic gyro suspension system for the Gravity Probe B experiment

Science.gov (United States)

Wu, Chang-Huei

1994-12-01

The Gravity Probe B experiment is a satellite-based experiment primarily designed to test two aspects of Einstein's General Theory of Relativity by observing the spin axis drift of near-perfect gyroscopes in a 650-km circular polar orbit. The goal of this experiment is to measure the drift angles to an accuracy of 0.3 milli-arcsec after one year in orbit. As a result, electrostatically suspended free-spinning gyroscopes operating at a very low temperature became the final choice for their ultra-low Newtonian torque-induced drift rate. The Conventional AC current-driven suspension system faces two fundamental difficulties for ground gyro testing. Field emission causes rotor charging and arcing with an imperfect electrode or rotor surfaces because the electric field intensity needed to support a solid rotor in the 1-g field is more than 107 V/m. The system not only becomes unstable at a high rotor charge, which can be more than 500 volts, but may also lose control in case of arcing. Both the high voltage AC suspension signal and the high frequency (1 MHz) signal for rotor position sensing interfere with the superconducting SQUID magnetometer for spin axis readout through inductive coupling. These problems were resolved by using DC voltage to generate a suspension force and a low frequency position sensor. In addition to the Input/Output linearization algorithm developed to remove the system nonlinearity for global stability and dynamic performance, we also minimized the electric field intensity to reduce rotor charging. Experimental results verified the desired global stability and satisfactory dynamic performance. The problem of rotor charging is virtually eliminated. More importantly, the DC system is compatible with the SQUID readout system in the Science Mission configuration. Consequently, experiments in low magnetic field at a sub-micro-gauss level for SQUID design verification and trapped flux distribution study were finally realizable in ground environment

An Improved Genetic Algorithm to Optimize Spatial Locations for Double-Wishbone Type Suspension System with Time Delay

Directory of Open Access Journals (Sweden)

Qiang Li

2018-01-01

Full Text Available By taking account of double-wishbone independent suspension with two unequal-length arms, the coordinate values of articulated geometry are based on structural limitations and constraint equations of alignment parameters. The sensitivities of front wheel alignment parameters are analyzed using the space analytic geometry method with insight module in ADAMS® software. The multiobjective optimization functions are designed to calculate the coordinate values of hardpoints with front suspension since the effect of time delay due to wheelbase can be easily obtained by vehicle speed. The K&C characteristics have been investigated using GA solutions in the simulation environment. The camber angle decreases from 1.152° to 1.05° and toe-in angle reduces from 1.036° to 0.944°. The simulation results demonstrate that the suggested optimization method is able to satisfy the suspension motion to enhance ride comfort. Experimental results, obtained by K&C test bench, also indicate that the optimized suspension can track the desired trajectory while keeping the vehicle performance in various road conditions.

Effect of Chemical Stabilizers in Silver Nanoparticle Suspensions on Nanotoxicity

International Nuclear Information System (INIS)

Bae, Eun Joo; Park, Hee Jin; Park, Jun Su; Yoon, Je Yong; Yi, Jong Heop; Kim, Young Hun; Choi, Kyung Hee

2011-01-01

Colloidal silver nanoparticles (AgNPs) have been commercialized as the typically stabilized form via the addition of a variety of surfactants or polymers. Herein, to examine the effects of stabilizing AgNPs in suspension, we modified the surface of bare AgNPs with four type of surfactants (NaDDBS, SDS, TW80, CTAB) and polymers (PVP, PAA, PAH, CMC). The modified AgNPs was applied to compare suspension stability and nanotoxicity test using Escherichia coli (E. coli) as a model organism. Modification of AgNPs surface using chemical stabilizer may be not related with molecular weight, but chemical structure such as ionic state and functional group of stabilizer. In this study, it is noteworthy that AgNPs modified with a cationic stabilizer (CTAB, PAH) were importantly toxic to E. coli, rather than anionic stabilizers (NaDDBS, SDS). Comparing similar anionic stabilizer, i.e., NaDDBS and SDS, the result showed that lipophilicity of chemical structure can affect on E. coli, because NaDDBS, which contains a lipophilic benzene ring, accelerated the cytotoxicity of AgNPs. Interestingly, none of the stabilizers tested, including biocompatible nonionic stabilizers (i.e., TW80 and cellulose) caused a reduction in AgNP toxicity. This showed that toxicity of AgNPs cannot be reduced using stabilizers

Effect of Chemical Stabilizers in Silver Nanoparticle Suspensions on Nanotoxicity

Energy Technology Data Exchange (ETDEWEB)

Bae, Eun Joo; Park, Hee Jin; Park, Jun Su; Yoon, Je Yong; Yi, Jong Heop [Seoul National University, Seoul (Korea, Republic of); Kim, Young Hun [Kwangwoon University, Seoul (Korea, Republic of); Choi, Kyung Hee [National Institute of Environmental Research, Incheon (Korea, Republic of)

2011-02-15

Colloidal silver nanoparticles (AgNPs) have been commercialized as the typically stabilized form via the addition of a variety of surfactants or polymers. Herein, to examine the effects of stabilizing AgNPs in suspension, we modified the surface of bare AgNPs with four type of surfactants (NaDDBS, SDS, TW80, CTAB) and polymers (PVP, PAA, PAH, CMC). The modified AgNPs was applied to compare suspension stability and nanotoxicity test using Escherichia coli (E. coli) as a model organism. Modification of AgNPs surface using chemical stabilizer may be not related with molecular weight, but chemical structure such as ionic state and functional group of stabilizer. In this study, it is noteworthy that AgNPs modified with a cationic stabilizer (CTAB, PAH) were importantly toxic to E. coli, rather than anionic stabilizers (NaDDBS, SDS). Comparing similar anionic stabilizer, i.e., NaDDBS and SDS, the result showed that lipophilicity of chemical structure can affect on E. coli, because NaDDBS, which contains a lipophilic benzene ring, accelerated the cytotoxicity of AgNPs. Interestingly, none of the stabilizers tested, including biocompatible nonionic stabilizers (i.e., TW80 and cellulose) caused a reduction in AgNP toxicity. This showed that toxicity of AgNPs cannot be reduced using stabilizers.

49 CFR 592.7 - Suspension, revocation, and reinstatement of suspended registrations.

Science.gov (United States)

2010-10-01

... vehicle during the time that its registration has been suspended. (d) Effect of suspension or revocation... date of the suspension or revocation all vehicles that it imported to which it has not affixed a... 49 Transportation 7 2010-10-01 2010-10-01 false Suspension, revocation, and reinstatement of...

29 CFR 98.600 - How do suspension and debarment actions start?

Science.gov (United States)

2010-07-01

... 29 Labor 1 2010-07-01 2010-07-01 true How do suspension and debarment actions start? 98.600 Section 98.600 Labor Office of the Secretary of Labor GOVERNMENTWIDE DEBARMENT AND SUSPENSION... debarment actions start? When we receive information from any source concerning a cause for suspension or...

Action of peracetic acid on Escherichia coli and Staphylococcus aureus in suspension or settled on stainless steel surfaces

Directory of Open Access Journals (Sweden)

Kunigk Leo

2001-01-01

Full Text Available The efficiency of a commercial peracetic acid sanitizer on destruction of Staphylococcus aureus and Escherichia coli was evaluated using two distinct methods. The first method is the AOAC suspension test and the second is a method proposed by one of the authors in which the microbial cells are settled on a stainless steel surface and then treated with the sanitizer. The results showed that when in suspension S. aureus was more resistant to the sanitizer than E. coli. When S. aureus was settled on the stainless steel surface, the contact time between the sanitizer and the microorganisms to attain a 6.5 log reduction in the number of viable cells was three times greater than when the cells were in suspension.

Levels of vibration transmitted to the operator of the tractor equipped with front axle suspension

Directory of Open Access Journals (Sweden)

Daniele Pochi

2013-09-01

Full Text Available In recent years the comfort and the preservation of the health of the operators became central issues in the evolution of agricultural machinery and led to the introduction of devices aimed at improving working conditions. Thereby, for instance, the presence of air conditioner, soundproof cab and driver seat suspension became normal on agricultural tractors. The vibrations are one of the most complex issues to deal with, being determined by the characteristics and interaction of elements such as tyres, axles, mainframe, cab and seat suspension. In this respect, manufacturers are trying to improve their products, even integrating these elements with new devices such as the suspension on the front axle of the tractor, aimed at reducing the level of vibrations during the transfers at high speed. One of these underwent tests at CRA-ING. Since its purpose is to reduce the level of vibration transmitted to the driver, their measurements in different points of the tractor and in different operating conditions, were compared in order to evaluate the effectiveness of the device, expressed as time of exposure. The suspension system of the front axle is designed to absorb the oscillations (especially pitching determined by irregularities in the road surface, allowing an increased control of the vehicle at high speed, as demonstrated by the test results and confirmed by the driving impressions outlined by the operator. The action of the device under these conditions results in an increase of the exposure time, important fact because of the relevance of the road transfer operations of tractors with mounted implements or trailers to tow and of the tendency to increase the speed limit for the road tractors (in Germany were brought to 50 km h–1 for several years. The action just described is less evident with increasing irregularity of the road surface and with the decrease of the travel speed. Nevertheless, in such conditions, the device appears to

The Effect of Topical Sucralfate Suspension on Oral Aphthae

Directory of Open Access Journals (Sweden)

Z. Delavarian

2007-06-01

Full Text Available Objectives: The purpose of this study was to determine the efficacy of oral sucralfate suspension (1gr/10ml in the treatment of recurrent aphthous stomatitis (RAS.Materials and Methods: Fifty-five patients with oral aphthae were included in this randomized, double-blind, placebo-controlled clinical trial conducted in the Department of Oral Medicine, School of Dentistry, Mashhad University of Medical Sciences. In thefirst part of the study, all subjects were instructed to rinse with a 10% suspension of sucralfate or placebo, 4 times a day for 2 weeks. Clinical examination was performed two times a week. The second part consisted of topical use of sucralfate or placebo 2times a day for 4 weeks, followed by biweekly inspections for 6 months.The size and number of the ulcers along with pain severity were assessed in the course of the pretreatment and treatment phases. Recurrence was evaluated during the follow up period. Pearson, χ2, and Fisher’s exact tests were used for statistical analysis.Results: On the fourth day of the study, pain relief was encountered in 59% and 14% of the case and control patients, respectively. Also, 63% of the ulcers in the sucralfate group and 71% in the placebo group showed size-reduction on the first visit. During the first 7 days of treatment, the number of ulcers showed reduction in both groups, which was significantly larger in the case group.Conclusion: A 10% suspension of sucralfate accelerated pain relief in aphthous patients and its use is recommended as an adjunct for the treatment of RAS.

Antidepressant, antioxidant and neurotrophic properties of the standardized extract of Cocos nucifera husk fiber in mice.

Science.gov (United States)

Lima, Eliane Brito Cortez; de Sousa, Caren Nádia Soares; Vasconcelos, Germana Silva; Meneses, Lucas Nascimento; E Silva Pereira, Yuri Freitas; Ximenes, Naiara Coelho; Santos Júnior, Manuel Alves; Matos, Natália Castelo Branco; Brito, Rayanne; Miron, Diogo; Leal, Luzia Kalyne Almeida Moreira; Macêdo, Danielle; Vasconcelos, Silvânia Maria Mendes

2016-07-01

The plant Cocos nucifera and its derivatives have shown antidepressant-like effects, although its hydroalcoholic extract has not been studied with this end in mind. Therefore, we decided to determine the antidepressant-like effects of the standardized hydroalcoholic extract of Cocos nucifera husk fiber (HECN) as well as oxidative alterations in the prefrontal cortex (PFC), hippocampus (HC) and striatum (ST), and the levels of brain-derived neurotrophic factor (BDNF) in the HC of mice. The extract was characterized based on the content of total polyphenols as well as two phenol compounds-catechin and chlorogenic acid-by HPLC-PDA. Male animals were treated per os (p.o.) for 7 days with distilled water or HECN (50, 100 or 200 mg/kg), or intraperitoneally with vitamin E (Vit E 400 mg/kg). One hour after the last drug administration, the animals were submitted to the open field test, forced swimming test (FST), tail suspension test (TST) and, immediately after the behavioral tests, had their brain removed for neurochemical determinations. The results showed that HECN100 decreased the immobility time in the FST and TST presenting, thus demonstrating an antidepressant-like effect. The administration of HECN decreased malondialdehyde levels in all doses and brain areas studied with the exception of HECN50 in the HC. The administration of HECN also decreased nitrite levels in all doses and brain regions studied. HECN100 also increased the levels of BDNF in HC of mice. In conclusion, we demonstrated that HECN has antidepressant-like properties, probably based on its antioxidant and neurotrophic effects, and is thus relevant for the treatment of depression.

Cipadesin A, a bioactive ingredient of Xylocarpus granatum, produces antidepressant-like effects in adult mice.

Science.gov (United States)

Gao, Qiang; Gao, Yuan; Song, Han; Li, Jianli; Wu, Yibing; Shi, Xiaowei; Shi, Haishui; Ma, Yuxia

2016-10-28

Xylocarpus granatum Koenig, widely used in folk medicine in southeast countries, has been reported to exert neuropharmacological activities as well as mood regulation. The neuroprotective activities of limonoids, riches in X. granatum, are poorly understood. To investigate the potential antidepressant-like effects and the underlying mechanisms of cipadesin A, one limonoid component, extracted from X. granatum, in acute stress-induced depression mouse models. Antidepressant-like effects of cipadesin A were investigated through behavioral tests, and potential mechanism was assessed by neuroendocrine system. Antidepressant-like effects of cipadesin A (5, 15, 50mg/kg/day for 7days, intragastrically) were estimated through forced-swimming test (FST), tail suspension test (TST) and open field test (OFT). Effects of cipadesin A on hypothalamus-pituitary- adrenal (HPA) axis were evaluated by analysis of serum corticosterone (CORT) and adrenocorticotropic hormone (ACTH) using enzyme-linked immunosorbent assay (ELISA). Cipadesin A administration significantly reduced the floating time in the FST and immobility time in the TST (15-50mg/kg). Cipadesin A dose-dependently increased the time in the central zone in the OFT (5-50mg/kg), without altering the locomotor activity. Moreover, repeated cipadesin A treatment significantly inhibited the increase levels of serum CORT (5-50mg/kg), ACTH (15-50mg/kg) following the forced swimming, but not in the absence of stress. Cipadesin A has antidepressant-like activities in acute stressed mice model of depression, which likely occurs by inhibiting the HPA axis activity response to stress. These data support further exploration for developing cipadesin A as a potential agent to treat depression and anxiety disorders. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.