Experimental Wave Component Analysis as Applied to Ship Wave Systems Part I Analysis of Available Methods and Evaluation of Some Experimental Data

http://deepblue.lib.umich.edu/bitstream/2027.42/96594/1/39015087359025.pd

Light bottom squark and gluino confront electroweak precision measurements

We address the compatibility of a light sbottom (mass 2\sim 5.5 \gev) and a light gluino (mass 12\sim 16 \gev) with electroweak precision measurements. Such light particles have been suggested to explain the observed excess in the $b$ quark production cross section at the Tevatron. The electroweak observables may be affected by the sbottom and gluino through the SUSY-QCD corrections to the $Zbb$ vertex. We examine, in addition to the SUSY-QCD corrections, the electroweak corrections to the gauge boson propagators from the stop which are allowed to be light from the SU(2)$_L$ symmetry. We find that this scenario is strongly disfavored from electroweak precision measurements unless the heavier sbottom mass eigenstate is lighter than 180\gev and the left-right mixing in the stop sector is sufficiently large. This implies that one of the stops should be lighter than about 98\gev.Comment: 4 pages, revtex, 2 figures. Reference added, version to appear in Phys.Rev.Let

Intention to donate via social network sites (SNSs): A comparison study between Malaysian and South Korean users

Purpose: The purpose of this paper is to explore the differences in the external factors influencing intention to donate via social network sites (SNSs), and the online donation knowledge and awareness effect on the willingness to donate via SNS in the future between Malaysian and South Korean users. Design/methodology/approach: In total, 288 samples’ data obtained from online survey using the snowball technique were analyzed through using cross-tabulation with χ2 tests and multiple regression analysis. Findings: The results show that there is no significant difference between those countries regarding the online donation knowledge and awareness. However, the online donation knowledge and awareness significantly affect the willingness to donate via SNSs for South Korean, but not for Malaysian. As for Malaysian, the results reveal that only SNS features factor does significantly influence the attitude toward online donations. As for South Korean, the charity project and internet technology features factor significantly influence the attitude toward online donations. The attitude toward online donations of both countries influences on their intention to donate via SNS. Research limitations/implications: The sample was gathered from certain regions in Malaysia and South Korea, and had slightly unbalanced characteristics (i.e. age), limiting the generalizability to the general population of both countries. Practical implications: The findings suggest that non-profit organizations should consider the culture context in planning their future SNS donation program and focus on how to deal with the internet issues (e.g. trust, security), SNS features and charity project. As for Malaysian, promoting the internet and online donation awareness should be the priority before engaging in SNS donation program. Originality/value: Whilst research on culture context in donation area is plentiful, the area of SNS donation remains underexplored. This paper offers an in-depth understanding of what influences SNS donation related to the identified culture context

Total knee arthroplasty for osteoarthritis secondary to extra-articular malunions

SummaryIntroductionPost-traumatic total knee arthroplasty for extra-articular malunion requires correction of the deformity, either through asymmetrical bone resection (possibly inducing ligaments imbalance) or osteotomy at the time of arthroplasty. We report the results of a continuous multicenter, retrospective series of 78 patients (18 implants with osteotomy) with a mean 4 years of follow-up. The hypothesis is that the selected procedure requires to be based on the deformity's location and severity.PatientsWith a mean age of 63 years (younger in the osteotomy group), 38 patients had femoral malunion, 36 had tibial malunion, and four had a combined malunion. There were 70 frontal deformities (48 varus and 22 valgus) and 10 rotational deformities, often diaphyseal, four of which more than 20°. Twelve patients had a history of infection; eight had frontal laxity greater than 10°, and 15 a limited range of motion in flexion. In 70 cases, semi- or nonconstrained implants were used, and in eight cases more constrained implants, including four hinge prostheses.ResultsWe observed two deep infections, one case of avulsion of the extensor mechanism, and two cases of aseptic loosening with femoral malunion and varus deformity. Two osteotomies resulted in nonunion, one with internal fixation devices mobilization requiring revision using extension rods. The function and pain scores were significantly improved. The mobility improvements were moderate but did not compromise the surgical procedure main objective. The preoperative hip-knee angle was corrected with both techniques. Only the function score gain was greater for the isolated arthroplasty procedures.Discussion and conclusionThe indications for arthroplasty alone were extended to 20° varus and 15° valgus, with no major residual laxity. Beyond 10°, hinge prosthesis should be available. Associated osteotomy can correct rotational deformities that cannot be compensated with bone cuts. In deformities that are close to the joint, osteotomy facilitates implantation of moderately constrained prosthesis. This indication is based on CAT scan rotational deformities measurements because rotational deformities require an osteotomy, and/or the presence of extraligamentous deformity that cannot be reduced with collateral ligaments surgical release.Level of evidenceLevel 4. Non-controlled retrospective study

Combining Theoretical and Experimental Techniques to Study Murine Heart Transplant Rejection

The quality of life of organ transplant recipients is compromised by complications associated with life-long immunosuppression, such as hypertension, diabetes, opportunistic infections, and cancer. Moreover, the absence of established tolerance to the transplanted tissues causes limited long-term graft survival rates. Thus, there is a great medical need to understand the complex immune system interactions that lead to transplant rejection so that novel and effective strategies of intervention that redirect the system toward transplant acceptance (while preserving overall immune competence) can be identified. This study implements a systems biology approach in which an experimentally based mathematical model is used to predict how alterations in the immune response influence the rejection of mouse heart transplants. Five stages of conventional mouse heart transplantation are modeled using a system of 13 ordinary differential equations that tracks populations of both innate and adaptive immunity as well as proxies for pro- and anti-inflammatory factors within the graft and a representative draining lymph node. The model correctly reproduces known experimental outcomes, such as indefinite survival of the graft in the absence of CD4(+) T cells and quick rejection in the absence of CD8(+) T cells. The model predicts that decreasing the translocation rate of effector cells from the lymph node to the graft delays transplant rejection. Increasing the starting number of quiescent regulatory T cells in the model yields a significant but somewhat limited protective effect on graft survival. Surprisingly, the model shows that a delayed appearance of alloreactive T cells has an impact on graft survival that does not correlate linearly with the time delay. This computational model represents one of the first comprehensive approaches toward simulating the many interacting components of the immune system. Despite some limitations, the model provides important suggestions of experimental investigations that could improve the understanding of rejection. Overall, the systems biology approach used here is a first step in predicting treatments and interventions that can induce transplant tolerance while preserving the capacity of the immune system to protect against legitimate pathogens

Methanol Extract of Hydroclathrus clathratus Inhibits Production of Nitric Oxide, Prostaglandin E2 and Tumor Necrosis Factor-&#945 in Lipopolysaccharidestimulated BV2 Microglial Cells via Inhibition of NF-&#954B Activity

Purpose: Hydroclathrus clathratus is a brown marine seaweed known to possess anti-cancer, anti-herpetic, and anti-coagulant activities. The present study is aimed at investigating some anti-inflammatory effects of H. clathratus.Methods: We investigated the anti-inflammatory effects of the methanol extract of H. clathratus (MEHC) by expression of mRNA and protein using RT-PCR and Western blot analysis in lipopolysaccharide (LPS)-stimulated BV2 microglial cells. The level of nitric oxide (NO) production was analyzed using Griess reaction. The release of prostaglandin E2 (PGE2) and tumor necrosis factor-α (TNF-α) were determined using sandwich ELISA. NF-κB activation was detected using EMSA methods.Results: The results obtained indicate that the extract (MEHC) inhibited LPS-induced NO, PGE2, and TNF-α production without any significant cytotoxicity (p < 0.05). MEHC also inhibited production of inducible NO synthase (iNOS), cyclooxygenase-2 (COX-2) and TNF-α mRNA in LPS-stimulated BV2 microglial cells. In addition, MEHC significantly reduced (p < 0.05) nuclear translocation of the nuclear factor-κB (NF-κB) subunits, p50 and p65, and its DNA-binding activity in LPS-stimulated BV2 microglial cells.Conclusion: These results suggest that MEHC suppresses the induction of TNF-α, as well as iNOS and COX-2 expression, by blocking LPS-induced NF-κB activation.Keywords: Hydroclathrus clathratus, Nitric oxide, Prostaglandin E2, Tumor necrosis factor-α, Nuclear factor-κ

Hadronic production of light color-triplet Higgs bosons: an alternative signature for GUT

The conventional signature for grand unified theories (GUT) is the proton decay. Recently, some models in extra dimensions or with specific discrete symmetries, which aim at solving the doublet-triplet problem, allow the color-triplet in the TeV mass region by suppressing the Yukawa couplings of the triplets to matter fermions. We study the hadronic production and detection of these TeV colored Higgs bosons as an alternative signature for GUT, which would behave like massive stable charged particles in particle detectors producing a striking signature of a charged track in the central tracking system and being ionized in the outer muon chamber. We found that the LHC is sensitive to a colored Higgs boson up to about 1.5 TeV. If the color-triplets are stable in cosmological time scale, they may constitute an interesting fraction of the dark matter.Comment: We added the description of a model by Goldberger et al.-- a 5D SU(5) SUSY model in a slice of AdS space with special boundary conditions to suppress proton decay. The color-triplet also has a TeV mas

Large effects on \BsBs mixing by vector-like quarks

We calculate the contributions of the vector-like quark model to \BsBs mixing, taking into account the constraints from the decay $B\to X_s\gamma$. In this model the neutral bosons mediate flavor-changing interactions at the tree level. However, \BsBs mixing is dominated by contributions from the box diagrams with the top quark and the extra up-type quark. In sizable ranges of the model parameters, the mixing parameter $x_s$ is much different from the standard model prediction.Comment: 11 pages, 4 figures, To be published in Phys. Rev.