108 research outputs found
Lateral dynamics simulation of webs having cross-machine direction variation
Webs often include sectional variation in caliper or modulus of elasticity as a result of undesirable manufacturing variation or by intentional design. These variations influence wrinkle formation and tracking control in multi-span web handling systems. This paper shares the results of finite element simulations of the lateral dynamics of webs having variation in thickness and modulus in cross-machine direction. Span length and machine-direction bulk strain were varied and the effects on lateral steering and wrinkle formation were simulated for a variety of inhomogeneous webs.Key variables affecting the lateral steering include the CMD location of the thick section and its width, the stiffness of the thick section, the z-direction bias of the thick section relative to the roller surface, the average strain in the composite web and the span length/width ratio. The web shifted in most cases toward the half of the web having the thick section, though not all. The combination of a web with a thick, stiff section having a width 1/10-1/6 that of the base web, coincident with the web edge, in long spans with low strain generated the largest lateral shift. Wrinkles were generated for some conditions where the thick section was located on or near web centerline
The Enabler: A reevaluation of design concepts and construction of a scaled model
The basic objective of the student's work this quarter was to make an in depth examination of the design concepts used on the lunar vehicle 'The Enabler'. Several changes were made to the vehicle including a redesigned wheel, a more compact boom and a reduced articulation angle. The vehicle's final dimensions were determined through an optimization process by defining mathematical equations for several of the vehicle's defined objectives. These included the ability to scale a one meter object, traverse a one meter crevice, and maintain a wheel-to-wheel clearance of three inches while at maximum articulation. The final dimensions of the vehicle were used to construct an approximate 1/4 scale model of the chassis and wheels. The boom, however, was constructed on a 1/5 scale (from the original design). This was due to the redesign of the boom and the limitations of the constructing material and PVC fittings
Systemic Antibiotic Therapy Reduces Circulating Inflammatory Dendritic Cells and Treg-Th17 Plasticity in Periodontitis
Periodontitis (PD) is a common dysbiotic inflammatory disease that leads to local bone deterioration and tooth loss. PD patients experience low-grade bacteremias with oral microbes implicated in the risk of heart disease, cancer, and kidney failure. Although Th17 effectors are vital to fighting infection, functional imbalance of Th17 effectors and regulatory T cells (Tregs) promote inflammatory diseases. In this study, we investigated, in a small pilot randomized clinical trial, whether expansion of inflammatory blood myeloid dendritic cells (DCs) and conversion of Tregs to Th17 cells could be modulated with antibiotics (AB) as part of initial therapy in PD patients. PD patients were randomly assigned to either 7 d of peroral metronidazole/amoxicillin AB treatment or no AB, along with standard care debridement and chlorhexidine mouthwash. 16s ribosomal RNA analysis of keystone pathoge
A Minimally Replicative HIV-2 Live-Virus Vaccine ProtectsM. nemestrinafrom Disease after HIV-2287Challenge
AbstractM. nemestrinaimmunized with an apathogenic HIV-2 molecular clone (HIV-2KR) were protected from CD4 decline and disease upon challenge with HIV-2287, after any immunizing virus could be detected. Higher but not lower inocula of HIV-2KRwere protective against intravenous inoculation of either 105or 101TCID50of HIV-2287. Protected animals displayed substantial reductions in PBMC proviral burden (1–3 logs), viral titers (1–2 logs), and plasma viral RNA (2–4 logs) compared to unprotected or naive animals as early as 1 week postinfection. Plasma viral RNA became undetectable after 24 weeks in protected animals, but remained high in unprotected animals. No viral RNA was present in the spleen of the protected animal necropsied more than a year after challenge (though viral DNA was still present). No neutralizing responses could be demonstrated, but CTL activity was detected sooner and at higher levels after challenge in protected than in unprotected macaques. In this novel HIV-2 vaccine model, protection was clearly dose-dependent, and clearance of challenge virus RNA from the plasma did not require detectable ongoing replication of the immunizing virus at the time of challenge
Disk and Envelope Structure in Class 0 Protostars: II. High Resolution Millimeter Mapping of the Serpens Sample
We present high-resolution CARMA 230 GHz continuum imaging of nine deeply
embedded protostars in the Serpens Molecular Cloud, including six of the nine
known Class 0 protostars in Serpens. This work is part of a program to
characterize disk and envelope properties for a complete sample of Class 0
protostars in nearby low-mass star forming regions. Here we present CARMA maps
and visibility amplitudes as a function of uv-distance for the Serpens sample.
Observations are made in the B, C, D, and E antenna configurations, with B
configuration observations utilizing the CARMA Paired Antenna Calibration
System. Combining data from multiple configurations provides excellent
uv-coverage (4-500 klam), allowing us to trace spatial scales from 1e2 to 1e4
AU. We find evidence for compact disk components in all of the observed Class 0
protostars, suggesting that disks form at very early times (t<0.2 Myr) in
Serpens. We make a first estimate of disk masses using the flux at 50 klam,
where the contribution from the envelope should be negligible, assuming an
unresolved disk. The resulting disk masses range from 0.04 Msun to 1.7 Msun,
with a mean of approximately 0.2 Msun. Our high resolution maps are also
sensitive to binary or multiple sources with separations > 250 AU, but
significant evidence of multiplicity on scales <2000 AU is seen in only one
source.Comment: Accepted to the Astrophysical Journal Supplement
EVALUATION OF ULTRA-HIGH PERFORMANCE CONCRETE, FIBER REINFORCED SELF-CONSOLIDATING CONCRETE, AND MALP CONCRETE FOR PRESTRESSED GIRDER REPAIR (FHWA-OK-21-03)
Ultra-high performance concrete (UHPC), fiber-reinforced self-consolidating concrete, and magnesium alumino-liquid-phosphate (MALP) concrete all have significant potential for use in bridge repair in Oklahoma.
The project described in this report examined the use of these materials in repairs of prestressed concrete
girder continuity connections and beam end regions including both experimental testing and field
implementation. Bond between the repair materials and conventional concrete and corrosion behavior were
examined for each repair material. Twelve composite beam and continuity joint specimens were damaged and
repaired using FR-SCC, MALP concrete, and UHPC. All repair materials restored capacity of the joints. Six girder
specimens were loaded to failure in shear and repaired using FR-SCC, MALP concrete, and UHPC. Repaired
specimens exhibited similar performance for all three repair materials and measured capacities exceeded those
for the original beams in all cases. The soffit of the bridge deck cantilevers on the S.H. 3 bridge over Fulton
Creek in Beaver County, Oklahoma was repaired using pneumatically placed MALP mortar and the repairs were
monitored over time. Some difficulties were encountered in placing the material, but the repair exhibited good
performance over time. The continuity joints on the U.S. 183/412 bridge over Wolf Creek in Fort Supply,
Oklahoma were replaced using UHPC and load tests indicated the repair reestablished continuity.Final Report October 2018 - December 2020N
A novel subset of memory B cells is enriched in autoreactivity and correlates with adverse outcomes in SLE
We previously reported that some systemic lupus erythematosus (SLE) patients have a population of circulating memory B cells with >2-fold higher levels of CD19. We show here that the presence of CD19hi B cells correlates with long-term adverse outcomes. These B cells do not appear anergic, as they exhibit high basal levels of phosphorylated Syk and ERK1/2, signal transduce in response to BCR crosslinking, and can become plasma cells (PCs) in vitro. Autoreactive anti-Smith (Sm) B cells are enriched in this population and the degree of enrichment correlates with the log of the serum anti-Sm titer, arguing that they undergo clonal expansion before PC differentiation. PC differentiation may occur at sites of inflammation, as CD19hi B cells have elevated CXCR3 levels and chemotax in response to its ligand CXCL9. Thus, CD19hi B cells are precursors to anti-self PCs, and identify an SLE patient subset likely to experience poor clinical outcomes
Activity of the DNA minor groove cross-linking agent SG2000 (SJG-136) against canine tumours
BACKGROUND: Cancer is the leading cause of death in older dogs and its prevalence is increasing. There is clearly a need to develop more effective anti-cancer drugs in dogs. SG2000 (SJG-136) is a sequence selective DNA minor groove cross-linking agent. Based on its in vitro potency, the spectrum of in vivo and clinical activity against human tumours, and its tolerability in human patients, SG2000 has potential as a novel therapeutic against spontaneously occurring canine malignancies. RESULTS: In vitro cytotoxicity was assessed using SRB and MTT assays, and in vivo activity was assessed using canine tumour xenografts. DNA interstrand cross-linking (ICL) was determined using a modification of the single cell gel electrophoresis (comet) assay. Effects on cell cycle distribution were assessed by flow cytometry and measurement of γ-H2AX by immunofluorescence and immunohistochemistry. SG2000 had a multi-log differential cytotoxic profile against a panel of 12 canine tumour cell lines representing a range of common tumour types in dogs. In the CMeC-1 melanoma cell line, DNA ICLs increased linearly with dose following a 1 h treatment. Peak ICL was achieved within 1 h and no removal was observed over 48 h. A relationship between DNA ICL formation and cytotoxicity was observed across cell lines. The formation of γ-H2AX foci was slow, becoming evident after 4 h and reaching a peak at 24 h. SG2000 exhibited significant anti-tumour activity against two canine melanoma tumour models in vivo. Anti-tumour activity was observed at 0.15 and 0.3 mg/kg given i.v. either once, or weekly x 3. Dose-dependent DNA ICL was observed in tumours (and to a lower level in peripheral blood mononuclear cells) at 2 h and persisted at 24 h. ICL increased following the second and third doses in a repeated dose schedule. At 24 h, dose dependent γ-H2AX foci were more numerous than at 2 h, and greater in tumours than in peripheral blood mononuclear cells. SG2000-induced H2AX phosphorylation measured by immunohistochemistry showed good correspondence, but less sensitivity, than measurement of foci. CONCLUSIONS: SG2000 displayed potent activity in vitro against canine cancer cell lines as a result of the formation and persistence of DNA ICLs. SG2000 also had significant in vivo antitumour activity against canine melanoma xenografts, and the comet and γ-H2AX foci methods were relevant pharmacodynamic assays. The clinical testing of SG2000 against spontaneous canine cancer is warranted. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12917-015-0534-2) contains supplementary material, which is available to authorized users
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