1,286 research outputs found
A Preliminary Study of Trunk Kinematics during Walking in Normal Subjects
The purpose of this study was to systematically describe the three-dimensional trunk kinematics in normal subjects, to establish a baseline for comparison to future research in gait analysis and aid in the identification of pathological gait. Seventeen volunteers between the ages of twenty and fifty, who met criteria for normal subjects, participated in this study. Trunk kinematic data were collected using an optoelectronic technique. An ensemble average of trunk kinematic data in each of the cardinal planes was plotted in degrees of motion versus percentage of gait cycle. A distinct pattern of trunk kinematics during gait was found in this study. Trunk motion relative to the pelvis was of greater magnitude than motion relative to the lab in the frontal and transverse planes. Inter-subject variability ranged from 37% to 644%, with the greatest amount of variability occurring in measurements of trunk movement relative to the lab in all three planes. Stride to stride variability within subjects ranged from 28% to 182%, with the greatest amount of intra-subject variability in trunk movements relative to the pelvis
Transient activation of mucosal effector immune responses by resident intestinal bacteria in normal hosts is regulated by interleukin-10 signalling
Interleukin-10 (IL-10) is a key regulator of mucosal homeostasis. In the current study we investigated the early events after monoassociating germ-free (GF) wild type (WT) mice with an E. coli strain that we isolated previously from the cecal contents of a normal mouse housed under specific pathogen free (SPF) conditions. Our results show that IFN-γ secreted by mesenteric lymph node (MLN) cells from both IL-10 deficient mice and WT mice, stimulated ex vivo with E. coli lysate, was dramatically higher at day 4 after monoassociation compared to IFN-γ secreted by cells from GF mice without E. coli colonization. Production of IFN-γ rapidly and progressively declined after colonization of WT but not IL-10 deficient mice. E. coli lysate-stimulated WT MLN cells also produced IL-10 that peaked at day 4 and subsequently declined, but not as precipitously as IFN-γ. WT cells that express CD4, CD8, and NKp46 produced IFN-γ; WT CD4-positive cells and B cells produced IL-10. Recombinant IL-10 added to E. coli-stimulated MLN cell cultures inhibited IFN-γ secretion in a dose-dependent fashion. MLN cells from WT mice treated in vivo with neutralizing anti-IL-10 receptor antibody produced more IFN-γ compared with MLN cells from isotype control antibody-treated mice. These findings show that a resident E. coli that induces chronic colitis in monoassociated IL-10 deficient mice rapidly but transiently activates the effector immune system in normal hosts, in parallel with induction of protective IL-10 produced by B cells and CD4(+) cells that subsequently suppresses this response to mediate mucosal homeostasis. This article is protected by copyright. All rights reserved
Isospin splitting of the nucleon mean field
The isospin splitting of the nucleon mean field is derived from the Brueckner
theory extended to asymmetric nuclear matter. The Argonne V18 has been adopted
as bare interaction in combination with a microscopic three body force. The
isospin splitting of the effective mass is determined from the
Brueckner-Hartree-Fock self-energy: It is linear acording to the Lane ansatz
and such that for neutron-rich matter. The symmetry potential
is also determined and a comparison is made with the predictions of the
Dirac-Brueckner approach and the phenomenological interactions. The theoretical
predictions are also compared with the empirical parametrizations of neutron
and proton optical-model potentials based on the experimental nucleon-nucleus
scattering and the phenomenological ones adopted in transport-model simulations
of heavy-ion collisions. The direct contribution of the rearrangement term due
to three-body forces to the single particle potential and symmetry potential is
discussed.Comment: 8 pages, 10 figure
Identification and Cross-Directional Control of Coating Processes: Theory and Experiments
Of special industrial interest is the cross-directional control of continuous coating processes, where the cross-direction refers to the direction perpendicular to the substrate movement. The objective of the controller is to maintain a uniform coating under unmeasured process disturbances based on assumptions relevant to coating processes found in industry. A model for control design is developed. This model is used to derive a model predictive controller with the objective of maintaining flat profiles of coating across the substrate by varying the liquid flows along the cross direction. Actuator constraints, measurement noise, and model uncertainty are investigated to determine which of these limit the achivable closed loop performance. From a knowledge of the effect of these limitations on performance we determine how the plant could be modified to improve the coating uniformity. The theory developed throughout the paper is rigorously verified though experiments on an industrial pilot plant
T cell-mediated oral tolerance is intact in germ-free mice
Commensal enteric bacteria stimulate innate immune cells and increase numbers of lamina propria and mesenteric lymph node (MLN) T and B lymphocytes. However, the influence of luminal bacteria on acquired immune function is not understood fully. We investigated the effects of intestinal bacterial colonization on T cell tolerogenic responses to oral antigen compared to systemic immunization. Lymphocytes specific for ovalbumin–T cell receptor (OVA–TCR Tg+) were transplanted into germ-free (GF) or specific pathogen-free (SPF) BALB/c mice. Recipient mice were fed OVA or immunized subcutaneously with OVA peptide (323–339) in complete Freund's adjuvant (CFA). Although the efficiency of transfer was less in GF recipients, similar proportions of cells from draining peripheral lymph node (LN) or MLN were proliferating 3–4 days later in vivo in GF and SPF mice. In separate experiments, mice were fed tolerogenic doses of OVA and then challenged with an immunogenic dose of OVA 4 days later. Ten days after immunization, lymphocytes were restimulated with OVA in vitro to assess antigen-specific proliferative responses. At both high and low doses of OVA, cells from both SPF and GF mice fed OVA prior to immunization had decreased proliferation compared to cells from control SPF or GF mice. In addition, secretion of interferon (IFN)-γ and interleukin (IL)-10 by OVA–TCR Tg+ lymphocytes was reduced in both SPF and GF mice fed OVA compared to control SPF or GF mice. Unlike previous reports indicating defective humoral responses to oral antigen in GF mice, our results indicate that commensal enteric bacteria do not enhance the induction of acquired, antigen-specific T cell tolerance to oral OVA
A Modeling Study on the Sensitivities of Atmospheric Charge Separation According to the Relative Diffusional Growth Rate Theory to Nonspherical Hydrometeors and Cloud Microphysics
Collisional charge transfer between graupel and ice crystals in the presence of cloud droplets is considered the dominant mechanism for charge separation in thunderclouds. According to the relative diffusional growth rate (RDGR) theory, the hydrometeor with the faster diffusional radius growth is charged positively in such collisions. We explore sensitivities of the RDGR theory to nonspherical hydrometeors and six parameters (pressure, temperature, liquid water content, sizes of ice crystals, graupel, and cloud droplets). Idealized simulations of a thundercloud with two‐moment cloud microphysics provide a realistic sampling of the parameter space. Nonsphericity and anisotropic diffusional growth strongly control the extent of positive graupel charging. We suggest a tuning parameter to account for anisotropic effects not represented in bulk microphysics schemes. In a susceptibility analysis that uses automated differentiation, we identify ice crystal size as most important RDGR parameter, followed by graupel size. Simulated average ice crystal size varies with temperature due to ice multiplication and heterogeneous freezing of droplets. Cloud microphysics and ice crystal size thus indirectly determine the structure of charge reversal lines in the traditional temperature‐water‐content representation. Accounting for the variability of ice crystal size and potentially habit with temperature may help to explain laboratory results and seems crucial for RDGR parameterizations in numerical models. We find that the contribution of local water vapor from evaporating rime droplets to diffusional graupel growth is only important for high effective water content. In this regime, droplet size and pressure are the dominant RDGR parameters. Otherwise, the effect of local graupel growth is masked by small ice crystal sizes that result from ice multiplication
Histogram specification of 24-bit color images in the color difference (C-Y) color space
Histogram equalization and specification have been widely used to enhance information in a gray scale image, with histogram specification having the advantage of allowing the output histogram to be specified as compared to histogram equalization, which attempts to produce an output histogram that is uniform Unfortunately, expanding histogram techniques to color images is not very straightforward Since humans are sensitive to chromatic changes, care must be taken to ensure that incorrect colors are not produced. Additionally expanding the one-dimensional histogram used in gray level histogram techniques to a joint histogram (usually of three variables representing the primary colors of red, green, and blue) can yield specified histograms which have no physical meaning, hence making if difficult to determine the set of histograms required for a desired enhancement in this paper, we describe a method of extending gray level histogram specification to color images by performing histogram specification an the luminance, saturation, and hue components in the color difference C-Y color space. These methods take into account the relationship between the luminance and saturation components while yielding specified histograms that produce natural-looking results
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First Report of NRG Oncology/Radiation Therapy Oncology Group 0622: A Phase 2 Trial of Samarium-153 Followed by Salvage Prostatic Fossa Irradiation in High-Risk Clinically Nonmetastatic Prostate Cancer After Radical Prostatectomy.
PURPOSE: To investigate the utility of 153Sm lexidronam (Quadramet) in the setting of men with prostate cancer status post radical prostatectomy who develop biochemical failure with no clinical evidence of osseous metastases.
PATIENTS AND METHODS: Trial NRG Oncology RTOG 0622 is a single-arm phase 2 trial that enrolled men with pT2-T4, N0-1, M0 prostate cancer status post radical prostatectomy, who meet at least 1 of these biochemical failure criteria: (1) prostate-specific antigen (PSA) \u3e 1.0 ng/mL; (2) PSA \u3e 0.2 ng/mL if Gleason score 9 to 10; or (3) PSA \u3e 0.2 ng/mL if N1. Patients received 153Sm (2.0 mCi/kg intravenously × 1) followed by salvage external beam radiation therapy (EBRT) to the prostatic fossa (64.8-70.2 Gy in 1.8-Gy daily fractions). No androgen deprivation therapy was allowed. The primary objective was PSA response within 12 weeks of receiving 153Sm. The secondary objectives were to: (1) assess the completion rate for the regimen of 153Sm and EBRT; (2) evaluate the hematologic toxicity and other adverse events (AEs) at 12 and 24 weeks; and (3) determine the freedom from progression rate at 2 years.
RESULTS: A total of 60 enrolled eligible patients were included in this analysis. Median follow-up was 3.97 years. A PSA response was achieved in 7 of 52 evaluable patients (13.5%), compared with the 25% hypothesized. The 2-year freedom from progression rate was 25.5% (95% confidence interval 14.4%-36.7%), and the biochemical failure rate was 64.4% (95% CI 50.5%-75.2%). Samarium-153 was well tolerated, with 16 (of 60) grade 3 to 4 hematologic AEs and no grade 5 hematologic AEs. Radiation therapy was also well tolerated, with no grade 3 to 5 acute radiation therapy-related AEs and 1 grade 3 to 4 and no grade 5 late radiation therapy-related AEs.
CONCLUSIONS: Trial NRG Oncology RTOG 0622 did not meet its primary endpoint of PSA response, although the regimen of 153Sm and salvage EBRT was well tolerated. Although the toxicity profile supports study of 153Sm in high-risk disease, it may not be beneficial in men receiving EBRT
Antigen-Presenting Cell Production of IL-10 Inhibits T-Helper 1 and 17 Cell Responses and Suppresses Colitis in Mice
IL-10 deficient mice develop TH1/TH17-mediated colitis and IL-10-producing regulatory T cells suppress colitis, implicating IL-10 in maintaining mucosal homeostasis. We transferred germ-free (GF) or specific pathogen free (SPF) CD4+ cells from wild-type (wt) or IL-10−/− (ko) mice into wt or IL-10 ko Rag2−/− recipients to assess the relative importance of immunoregulatory IL-10 derived from T cells vs. antigen presenting cells (APC)
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