886 research outputs found
Parametrical optimization of laser surface alloyed NiTi shape memory alloy with Co and Nb by the Taguchi method
Different high-purity metal powders were successfully alloyed on to a nickel titanium (NiTi) shape memory alloy (SMA) with a 3 kW carbon dioxide (CO2) laser system. In order to produce an alloyed layer with complete penetration and acceptable composition profile, the Taguchi approach was used as a statistical technique for optimizing selected laser processing parameters. A systematic study of laser power, scanning velocity, and pre-paste powder thickness was conducted. The signal-to-noise ratios (S/N) for each control factor were calculated in order to assess the deviation from the average response. Analysis of variance (ANOVA) was carried out to understand the significance of process variables affecting the process effects. The Taguchi method was able to determine the laser process parameters for the laser surface alloying technique with high statistical accuracy and yield a laser surface alloying technique capable of achieving a desirable dilution ratio. Energy dispersive spectrometry consistently showed that the per cent by weight of Ni was reduced by 45 per cent as compared with untreated NiTi SMA when the Taguchi-determined laser processing parameters were employed, thus verifying the laser's processing parameters as optimum
Spacetime Emergence and General Covariance Transmutation
Spacetime emergence refers to the notion that classical spacetime "emerges"
as an approximate macroscopic entity from a non-spatio-temporal structure
present in a more complete theory of interacting fundamental constituents. In
this article, we propose a novel mechanism involving the "soldering" of
internal and external spaces for the emergence of spacetime and the twin
transmutation of general covariance. In the context of string theory, this
mechanism points to a critical four dimensional spacetime background.Comment: 11 pages, v2: version to appear in MPL
Three Generations in Minimally Extended Standard Models
We present a class of minimally extended standard models with the gauge group
where for all , anomaly
cancelation requires three generations. At low energy, we recover the Standard
Model (SM), while at higher energies, there must exist quarks, leptons and
gauge bosons with electric charges shifted from their SM values by integer
multiples of the electron charge up to . Since the value N=5 is
the highest consistent with QCD asymptotic freedom, we elaborate on the
3-5-1 model.Comment: 9 pages, v3: version to appear in PL
Dark Matter, Infinite Statistics and Quantum Gravity
We elaborate on our proposal regarding a connection between global physics
and local galactic dynamics via quantum gravity. This proposal calls for the
concept of MONDian dark matter which behaves like cold dark matter at cluster
and cosmological scales but emulates modified Newtonian dynamics (MOND) at the
galactic scale. In the present paper, we first point out a surprising
connection between the MONDian dark matter and an effective gravitational
Born-Infeld theory. We then argue that these unconventional quanta of MONDian
dark matter must obey infinite statistics, and the theory must be fundamentally
non-local. Finally, we provide a possible top-down approach to our proposal
from the Matrix theory point of view.Comment: 15 pages, v3: revised version to appear in PR
Interferon-gamma Inducible Protein 10 up-regulated by acute-phase graft injury induced late-phase cisplatin resistance after liver transplantation
published_or_final_versio
'Obligate' anaerobic Salmonella strain YB1 suppresses liver tumor growth and metastasis in nude mice
published_or_final_versio
Cavity Design and Optimization for Organic Microcavity OLEDs
We report on detailed simulations of the emission from microcavity OLEDs consisting of widely used organic materials, n,N'-di(naphthalene-1-yl)-N,N'-diphenyl-benzidine (NPB) as a hole transport layer and tris (8-hydroxyquinoline) (Alq3) as emitting and electron transporting layer. The thick silver film was considered as a top mirror, while silver or copper films on quartz substrate were considered as bottom mirrors. The electroluminescence emission spectra, electric field distribution inside the device, carrier density and recombination rate were calculated as a function of the position of the emission layer, i.e. interface between NPB and Alq3. In order to achieve optimum emission from a microcavity OLED, it is necessary to align the position of the recombination region with the antinode of the standing wave inside the cavity. Once the optimum structure has been determined, the microcavity OLED devices were fabricated and characterized. The experimental results have been compared to the simulations and the influence of the emission region width and position on the performance of microcavity OLEDs was discussed
Use of electroacupuncture to accelerate the antidepressant action of selective serotonin reuptake inhibitors: a single-blind, randomised, controlled study
published_or_final_versio
Trust as a mediator in the relationship between childhood sexual abuse and IL-6 level in adulthood
Childhood sexual abuse (CSA) has been shown to predict the coupling of depression and inflammation in adulthood. Trust within intimate relationships, a core element in marital relations, has been shown to predict positive physical and mental health outcomes, but the mediating role of trust in partners in the association between CSA and inflammation in adulthood requires further study. The present study aimed to examine the impact of CSA on inflammatory biomarkers (IL-6 and IL-1β) in adults with depression and the mediating role of trust. A cross-sectional survey data set of adults presenting with mood and sleep disturbance was used in the analysis. CSA demonstrated a significant negative correlation with IL-6 level (r = -0.28, p<0. 01) in adults with clinically significant depression, while trust showed a significant positive correlation with IL-6 level (r = 0.36, p < .01). Sobel test and bootstrapping revealed a significant mediating role for trust between CSA and IL-6 level. CSA and trust in partners were revealed to have significant associations with IL-6 level in adulthood. Counterintuitively, the directions of association were not those expected. Trust played a mediating role between CSA and adulthood levels of IL-6. Plausible explanations for these counterintuitive findings are discussed
Clinical significance and therapeutic value of glutathione peroxidase 3 (GPx3) in hepatocellular carcinoma
AIMS:
We aimed to investigate the clinical significance of GPx3 in hepatocellular carcinoma (HCC) and to characterize its tumor suppressive role.
METHODS:
HCC patients (113) who underwent hepatectomy were recruited to examine the clinical relevance of GPx3. The tumor suppressive role of GPx3 was studied by administration of recombinant GPx3 (rGPx3) or over-expression of GPx3 in HCC cells in vitro and in vivo. The therapeutic value of GPx3 for HCC was further investigated using human induced pluripotent stem cell derived mesenchymal stem cells (hiPSC-MSCs) as its delivery vehicle.
RESULTS:
Down-regulation of GPx3 significantly correlated with advanced tumor stage (P = 0.024), venous infiltration (P = 0.043) and poor overall survival (P = 0.007) after hepatectomy. Lower plasma GPx3 in HCC patients was significantly associated with larger tumor size (P = 0.011), more tumor nodules (P = 0.032) and higher recurrence (P = 0.016). Over-expression of GPx3 or administration of rGPx3 significantly inhibited proliferation and invasiveness of HCC cells in vitro and in vivo. Tumor suppressive activity of GPx3 was mediated through Erk-NFκB-SIP1 pathway. GPx3 could be delivered by hiPSC-MSCs into the tumor and exhibited tumor suppressive activity in vivo.
CONCLUSIONS:
GPx3 is a tumor suppressor gene in HCC and may possess prognostic and therapeutic value for HCC patients.published_or_final_versio
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