49,042 research outputs found
Late events in osteosarcoma survivors : What can we learn from clinical trials in amputation versus limb salvage?
No full textIntroduction Limb salvage surgery using endoprosthesis, allografts or reconstructions is applied in about 85% of patients affected by osteosarcoma of the middle and/or distal femur. For the long term survivors one drawback in limb-salvage surgery is that endoprostheses have a limited duration and long-term prosthetic failure with the inherent high rate of reoperation remains a serious long-term problem. The purpose of this work is to evaluate the long term functional and quality of life results of limb salvage procedure compared with amputation in long term osteosarcoma survivors.
Materials and Methods A total of 112 osteosarcoma of the limb survivors, aged 16 to 52 years of age, treated between 1972 and 2005, < 20 of age at diagnosis were enrolled to this study.
Results Among the survivors who replied to the questionnaire, no significant differences existed in functional or psychological outcomes between survivors with limb salvage and those with amputation. Conclusion In limb-saved long term osteosarcoma survivors, after endoprostheses failure and repeated surgical procedures, the decision to undergo additional limb salvage procedures is difficult and multifaceted. Amputee survivors had a similar psychological and quality of life outcome compared limb salvage survivors
Precise restoration of cortical orientation maps explained by hebbian dynamics of geniculocortical connections
No full textt is widely assumed that experience dependence and variability of the individual layout of cortical columns are the hallmarks of activity-dependent self-organization during development. Recent optical imaging studies of visual cortical development seem to indicate a lack of such intinsic variability in visual cortical development. These studies showed that orientation maps which were forced to form independently for the left and right eye exhibited a high degree of similarity in area 18 of cat visual cortex [7, 4]. It has been argued that this result must be viewed are evidence for an innate predetermination of orientation preference if orientation preference is determined by the pattern of geniculocortical connections. Here we point out that the observed phenomenon can in fact be explained by the activity-dependent development of geniculocortical connections if geometric constraints and retinotopic organization of area 18 are taken into acount. In particular we argue that symmetries, which would lead to a strong variability of the emerging orientation map can be broken by boundary effects and interactions between the orientation preference map and the retinotopic organization. As a consequence independently developing orientation maps should exhibit the same layout in area 18, but not in area 17. Simulations of the formation of orientation columns in narrow areas indeed produce uniquely defined orientation preference maps irrespective of the particular set of stimuli driving the development
Measurement of the ratio of branching fractions B(B0→K∗0γ )/B(B0s→φγ ) and the directCP asymmetry inB 0→K∗0γ
No full textThe ratio of branching fractions of the radiative B decays B0→K⁎0γ and B0s→ϕγ has been measured using an integrated luminosity of 1.0 fb−1 of pp collision data collected by the LHCb experiment at a centre-of-mass energy of s√=7TeV. The value obtained is
B(B0→K⁎0γ)B(B0s→ϕγ)=1.23±0.06(stat.)±0.04(syst.)±0.10(fs/fd),
where the first uncertainty is statistical, the second is the experimental systematic uncertainty and the third is associated with the ratio of fragmentation fractions fs/fd. Using the world average value for B(B0→K⁎0γ), the branching fraction B(B0s→ϕγ) is measured to be (3.5±0.4)×10−5.
The direct CP asymmetry in B0→K⁎0γ decays has also been measured with the same data and found to be
ACP(B0→K⁎0γ)=(0.8±1.7(stat.)±0.9(syst.))%.
Both measurements are the most precise to date and are in agreement with the previous experimental results and theoretical expectations
Search for violation in decays and observation of the Cabibbo-suppressed decay
No full textWe search for violation by measuring a -odd asymmetry in the
Cabibbo-suppressed decay, and
in the Cabibbo-favored and
decays. We use 980 of data collected by the Belle detector running at the KEKB
asymmetric-energy collider. The -violating -odd parameter
is measured to be
and
where the first
uncertainty is statistical and the second is systematic. We also report the
first observation of the Cabibbo-suppressed decay . The branching fraction is measured relative to
that of the analogous Cabibbo-favored decay :
Feasibility of 4H-SiC p-i-n Diode for Sensitive Temperature Measurements between 20.5 K and 802 K
No full textFor the first time, we report on the performances of 4H-SiC p-i-n-diode temperature sensors for operating temperatures between 20.5 and 802 K. In this huge temperature range, three ranges of performance were identified with the limit temperatures at 78.2 and 176.3 K. In each of these ranges, a different dominant current transport mechanism is shown and in this paper, a detailed analysis and discussion are reported. The sensor performances were extracted from VD - T characteristics at different fixed ID values. In particular, at ID = 1 μ A and in the temperature range between 78.2 and 802 K, we found a sensor sensitivity of 2.3-3.4 mV/K with a rms temperature error, eT , of less than 4.2 K and the sensor shows an excellent linearity - quantified by the coefficient of determination R2 higher than 0.9993. For even lower temperatures (below 78.2 K), low measurement currents like 10 nA are required leading to a sensitivity of 5.8 mV/K, but a lower linearity (R2 = 0.9095) and an rms temperature error of 9.7 K which makes the sensor only partially usable in the temperature range between 20.5 and 78.2 K. Finally, the sensor performances are compared with other state-of-the-art solutions
Letter from Franklin K. Lane, Secretary of the Interior, to Representative Hayden
No full textLetter from Franklin K. Lane to Carl T. Hayden expressing his support for bill S.390 in establishing the Grand Canyon as a National Park
DNA fusion gene vaccination mobilizes effective anti-leukemic cytotoxic T lymphocytes from a tolerized repertoire
No full textThe majority of known human tumor-associated antigens derive from non-mutated self proteins. T cell tolerance, essential to prevent autoimmunity, must therefore be cautiously circumvented to generate cytotoxic T cell responses against these targets. Our strategy uses DNA fusion vaccines to activate high levels of peptide-specific CTL. Key foreign sequences from tetanus toxin activate tolerance-breaking CD4+ T cell help. Candidate MHC class Ibinding tumor peptide sequences are fused to the C terminus for optimal processing and presentation. To model performance against a leukemia-associated antigen in a tolerized setting, we constructed a fusion vaccine encoding an immunodominant CTL epitopederived from Friend murine leukemia virus gag protein (FMuLVgag) and vaccinated tolerant FMuLVgag-transgenic (gag-Tg) mice. Vaccination with the construct induced epitopespecificIFN-c-producing CD8+ T cells in normal and gag-Tg mice. The frequency and avidity of activated cells were reduced in gag-Tg mice, and no autoimmune injury resulted. However, these CD8+ T cells did exhibit gag-specific cytotoxicity in vitro and in vivo. Also, epitope-specific CTL killed FBL-3 leukemia cells expressing endogenous FMuLVgag antigen and protected against leukemia challenge in vivo. These results demonstrate a simple strategy to engage anti-microbial T cell help to activate epitope-specific polyclonal CD8+ T cell responses from a residual tolerized repertoire
First observation of the decay Bs0→K*0K*0
No full textThe first observation of the decay B0s→K∗0K∗0 is reported using 35 pb−1 of data collected by LHCb in proton–proton collisions at a centre-of-mass energy of 7 TeV. A total of 49.8±7.5 B0s→(K+π−)(K−π+) events are observed within ±50 MeV/c2 of the B0s mass and 746 MeV/c2 < mKπ < 1046 MeV/c2, mostly coming from a resonant B0s→K∗0K∗0 signal. The branching fraction and the CP-averaged K∗0 longitudinal polarization fraction are measured to be B(B0s→K∗0K∗0)=(2.81±0.46(stat.)±0.45(syst.)±0.34(fs/ fd))×10−5 and fL =0.31±0.12(stat.)±0.04(syst.)
JulianKarlBauer/fiber_orientation_tensors_2021: Add cubic parameterization
No full textBauer, J. K., & Böhlke, T. (2022). Variety of fiber orientation tensors. Mathematics and Mechanics of Solids, 10812865211057602.Please cite this software using the metadata from 'preferred-citation'
The K-T Extinction
No full textThis chapter from the book History of Life describes the results of the K-T extinction and looks at the Impact theory and a giant volcanic eruption as possible causes. The essay covers the catastrophic scenarios for extinction that could result from these events. After reviewing the paleontological record across the K-T boundary, the author concludes that it is not clear that the catastrophes themselves can explain the extinction patterns that we see in the fossil record. Educational levels: Graduate or professional, Undergraduate lower division, Undergraduate upper division
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